1 #ifndef USE_LIBSQLITE3 2 /* 3 ** 2001-09-15 4 ** 5 ** The author disclaims copyright to this source code. In place of 6 ** a legal notice, here is a blessing: 7 ** 8 ** May you do good and not evil. 9 ** May you find forgiveness for yourself and forgive others. 10 ** May you share freely, never taking more than you give. 11 ** 12 ************************************************************************* 13 ** This header file defines the interface that the SQLite library 14 ** presents to client programs. If a C-function, structure, datatype, 15 ** or constant definition does not appear in this file, then it is 16 ** not a published API of SQLite, is subject to change without 17 ** notice, and should not be referenced by programs that use SQLite. 18 ** 19 ** Some of the definitions that are in this file are marked as 20 ** "experimental". Experimental interfaces are normally new 21 ** features recently added to SQLite. We do not anticipate changes 22 ** to experimental interfaces but reserve the right to make minor changes 23 ** if experience from use "in the wild" suggest such changes are prudent. 24 ** 25 ** The official C-language API documentation for SQLite is derived 26 ** from comments in this file. This file is the authoritative source 27 ** on how SQLite interfaces are supposed to operate. 28 ** 29 ** The name of this file under configuration management is "sqlite.h.in". 30 ** The makefile makes some minor changes to this file (such as inserting 31 ** the version number) and changes its name to "sqlite3.h" as 32 ** part of the build process. 33 */ 34 #ifndef SQLITE3_H 35 #define SQLITE3_H 36 #include <stdarg.h> /* Needed for the definition of va_list */ 37 38 /* 39 ** Make sure we can call this stuff from C++. 40 */ 41 #ifdef __cplusplus 42 extern "C" { 43 #endif 44 45 46 /* 47 ** Provide the ability to override linkage features of the interface. 48 */ 49 #ifndef SQLITE_EXTERN 50 # define SQLITE_EXTERN extern 51 #endif 52 #ifndef SQLITE_API 53 # define SQLITE_API 54 #endif 55 #ifndef SQLITE_CDECL 56 # define SQLITE_CDECL 57 #endif 58 #ifndef SQLITE_APICALL 59 # define SQLITE_APICALL 60 #endif 61 #ifndef SQLITE_STDCALL 62 # define SQLITE_STDCALL SQLITE_APICALL 63 #endif 64 #ifndef SQLITE_CALLBACK 65 # define SQLITE_CALLBACK 66 #endif 67 #ifndef SQLITE_SYSAPI 68 # define SQLITE_SYSAPI 69 #endif 70 71 /* 72 ** These no-op macros are used in front of interfaces to mark those 73 ** interfaces as either deprecated or experimental. New applications 74 ** should not use deprecated interfaces - they are supported for backwards 75 ** compatibility only. Application writers should be aware that 76 ** experimental interfaces are subject to change in point releases. 77 ** 78 ** These macros used to resolve to various kinds of compiler magic that 79 ** would generate warning messages when they were used. But that 80 ** compiler magic ended up generating such a flurry of bug reports 81 ** that we have taken it all out and gone back to using simple 82 ** noop macros. 83 */ 84 #define SQLITE_DEPRECATED 85 #define SQLITE_EXPERIMENTAL 86 87 /* 88 ** Ensure these symbols were not defined by some previous header file. 89 */ 90 #ifdef SQLITE_VERSION 91 # undef SQLITE_VERSION 92 #endif 93 #ifdef SQLITE_VERSION_NUMBER 94 # undef SQLITE_VERSION_NUMBER 95 #endif 96 97 /* 98 ** CAPI3REF: Compile-Time Library Version Numbers 99 ** 100 ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header 101 ** evaluates to a string literal that is the SQLite version in the 102 ** format "X.Y.Z" where X is the major version number (always 3 for 103 ** SQLite3) and Y is the minor version number and Z is the release number.)^ 104 ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer 105 ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same 106 ** numbers used in [SQLITE_VERSION].)^ 107 ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also 108 ** be larger than the release from which it is derived. Either Y will 109 ** be held constant and Z will be incremented or else Y will be incremented 110 ** and Z will be reset to zero. 111 ** 112 ** Since [version 3.6.18] ([dateof:3.6.18]), 113 ** SQLite source code has been stored in the 114 ** <a href="http://www.fossil-scm.org/">Fossil configuration management 115 ** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to 116 ** a string which identifies a particular check-in of SQLite 117 ** within its configuration management system. ^The SQLITE_SOURCE_ID 118 ** string contains the date and time of the check-in (UTC) and a SHA1 119 ** or SHA3-256 hash of the entire source tree. If the source code has 120 ** been edited in any way since it was last checked in, then the last 121 ** four hexadecimal digits of the hash may be modified. 122 ** 123 ** See also: [sqlite3_libversion()], 124 ** [sqlite3_libversion_number()], [sqlite3_sourceid()], 125 ** [sqlite_version()] and [sqlite_source_id()]. 126 */ 127 #define SQLITE_VERSION "3.31.1" 128 #define SQLITE_VERSION_NUMBER 3031001 129 #define SQLITE_SOURCE_ID "2020-01-27 19:55:54 3bfa9cc97da10598521b342961df8f5f68c7388fa117345eeb516eaa837bb4d6" 130 131 /* 132 ** CAPI3REF: Run-Time Library Version Numbers 133 ** KEYWORDS: sqlite3_version sqlite3_sourceid 134 ** 135 ** These interfaces provide the same information as the [SQLITE_VERSION], 136 ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros 137 ** but are associated with the library instead of the header file. ^(Cautious 138 ** programmers might include assert() statements in their application to 139 ** verify that values returned by these interfaces match the macros in 140 ** the header, and thus ensure that the application is 141 ** compiled with matching library and header files. 142 ** 143 ** <blockquote><pre> 144 ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER ); 145 ** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 ); 146 ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 ); 147 ** </pre></blockquote>)^ 148 ** 149 ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION] 150 ** macro. ^The sqlite3_libversion() function returns a pointer to the 151 ** to the sqlite3_version[] string constant. The sqlite3_libversion() 152 ** function is provided for use in DLLs since DLL users usually do not have 153 ** direct access to string constants within the DLL. ^The 154 ** sqlite3_libversion_number() function returns an integer equal to 155 ** [SQLITE_VERSION_NUMBER]. ^(The sqlite3_sourceid() function returns 156 ** a pointer to a string constant whose value is the same as the 157 ** [SQLITE_SOURCE_ID] C preprocessor macro. Except if SQLite is built 158 ** using an edited copy of [the amalgamation], then the last four characters 159 ** of the hash might be different from [SQLITE_SOURCE_ID].)^ 160 ** 161 ** See also: [sqlite_version()] and [sqlite_source_id()]. 162 */ 163 SQLITE_API SQLITE_EXTERN const char sqlite3_version[]; 164 SQLITE_API const char *sqlite3_libversion(void); 165 SQLITE_API const char *sqlite3_sourceid(void); 166 SQLITE_API int sqlite3_libversion_number(void); 167 168 /* 169 ** CAPI3REF: Run-Time Library Compilation Options Diagnostics 170 ** 171 ** ^The sqlite3_compileoption_used() function returns 0 or 1 172 ** indicating whether the specified option was defined at 173 ** compile time. ^The SQLITE_ prefix may be omitted from the 174 ** option name passed to sqlite3_compileoption_used(). 175 ** 176 ** ^The sqlite3_compileoption_get() function allows iterating 177 ** over the list of options that were defined at compile time by 178 ** returning the N-th compile time option string. ^If N is out of range, 179 ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_ 180 ** prefix is omitted from any strings returned by 181 ** sqlite3_compileoption_get(). 182 ** 183 ** ^Support for the diagnostic functions sqlite3_compileoption_used() 184 ** and sqlite3_compileoption_get() may be omitted by specifying the 185 ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time. 186 ** 187 ** See also: SQL functions [sqlite_compileoption_used()] and 188 ** [sqlite_compileoption_get()] and the [compile_options pragma]. 189 */ 190 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS 191 SQLITE_API int sqlite3_compileoption_used(const char *zOptName); 192 SQLITE_API const char *sqlite3_compileoption_get(int N); 193 #else 194 # define sqlite3_compileoption_used(X) 0 195 # define sqlite3_compileoption_get(X) ((void*)0) 196 #endif 197 198 /* 199 ** CAPI3REF: Test To See If The Library Is Threadsafe 200 ** 201 ** ^The sqlite3_threadsafe() function returns zero if and only if 202 ** SQLite was compiled with mutexing code omitted due to the 203 ** [SQLITE_THREADSAFE] compile-time option being set to 0. 204 ** 205 ** SQLite can be compiled with or without mutexes. When 206 ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes 207 ** are enabled and SQLite is threadsafe. When the 208 ** [SQLITE_THREADSAFE] macro is 0, 209 ** the mutexes are omitted. Without the mutexes, it is not safe 210 ** to use SQLite concurrently from more than one thread. 211 ** 212 ** Enabling mutexes incurs a measurable performance penalty. 213 ** So if speed is of utmost importance, it makes sense to disable 214 ** the mutexes. But for maximum safety, mutexes should be enabled. 215 ** ^The default behavior is for mutexes to be enabled. 216 ** 217 ** This interface can be used by an application to make sure that the 218 ** version of SQLite that it is linking against was compiled with 219 ** the desired setting of the [SQLITE_THREADSAFE] macro. 220 ** 221 ** This interface only reports on the compile-time mutex setting 222 ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with 223 ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but 224 ** can be fully or partially disabled using a call to [sqlite3_config()] 225 ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], 226 ** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the 227 ** sqlite3_threadsafe() function shows only the compile-time setting of 228 ** thread safety, not any run-time changes to that setting made by 229 ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe() 230 ** is unchanged by calls to sqlite3_config().)^ 231 ** 232 ** See the [threading mode] documentation for additional information. 233 */ 234 SQLITE_API int sqlite3_threadsafe(void); 235 236 /* 237 ** CAPI3REF: Database Connection Handle 238 ** KEYWORDS: {database connection} {database connections} 239 ** 240 ** Each open SQLite database is represented by a pointer to an instance of 241 ** the opaque structure named "sqlite3". It is useful to think of an sqlite3 242 ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and 243 ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] 244 ** and [sqlite3_close_v2()] are its destructors. There are many other 245 ** interfaces (such as 246 ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and 247 ** [sqlite3_busy_timeout()] to name but three) that are methods on an 248 ** sqlite3 object. 249 */ 250 typedef struct sqlite3 sqlite3; 251 252 /* 253 ** CAPI3REF: 64-Bit Integer Types 254 ** KEYWORDS: sqlite_int64 sqlite_uint64 255 ** 256 ** Because there is no cross-platform way to specify 64-bit integer types 257 ** SQLite includes typedefs for 64-bit signed and unsigned integers. 258 ** 259 ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. 260 ** The sqlite_int64 and sqlite_uint64 types are supported for backwards 261 ** compatibility only. 262 ** 263 ** ^The sqlite3_int64 and sqlite_int64 types can store integer values 264 ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The 265 ** sqlite3_uint64 and sqlite_uint64 types can store integer values 266 ** between 0 and +18446744073709551615 inclusive. 267 */ 268 #ifdef SQLITE_INT64_TYPE 269 typedef SQLITE_INT64_TYPE sqlite_int64; 270 # ifdef SQLITE_UINT64_TYPE 271 typedef SQLITE_UINT64_TYPE sqlite_uint64; 272 # else 273 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; 274 # endif 275 #elif defined(_MSC_VER) || defined(__BORLANDC__) 276 typedef __int64 sqlite_int64; 277 typedef unsigned __int64 sqlite_uint64; 278 #else 279 typedef long long int sqlite_int64; 280 typedef unsigned long long int sqlite_uint64; 281 #endif 282 typedef sqlite_int64 sqlite3_int64; 283 typedef sqlite_uint64 sqlite3_uint64; 284 285 /* 286 ** If compiling for a processor that lacks floating point support, 287 ** substitute integer for floating-point. 288 */ 289 #ifdef SQLITE_OMIT_FLOATING_POINT 290 # define double sqlite3_int64 291 #endif 292 293 /* 294 ** CAPI3REF: Closing A Database Connection 295 ** DESTRUCTOR: sqlite3 296 ** 297 ** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors 298 ** for the [sqlite3] object. 299 ** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if 300 ** the [sqlite3] object is successfully destroyed and all associated 301 ** resources are deallocated. 302 ** 303 ** ^If the database connection is associated with unfinalized prepared 304 ** statements or unfinished sqlite3_backup objects then sqlite3_close() 305 ** will leave the database connection open and return [SQLITE_BUSY]. 306 ** ^If sqlite3_close_v2() is called with unfinalized prepared statements 307 ** and/or unfinished sqlite3_backups, then the database connection becomes 308 ** an unusable "zombie" which will automatically be deallocated when the 309 ** last prepared statement is finalized or the last sqlite3_backup is 310 ** finished. The sqlite3_close_v2() interface is intended for use with 311 ** host languages that are garbage collected, and where the order in which 312 ** destructors are called is arbitrary. 313 ** 314 ** Applications should [sqlite3_finalize | finalize] all [prepared statements], 315 ** [sqlite3_blob_close | close] all [BLOB handles], and 316 ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated 317 ** with the [sqlite3] object prior to attempting to close the object. ^If 318 ** sqlite3_close_v2() is called on a [database connection] that still has 319 ** outstanding [prepared statements], [BLOB handles], and/or 320 ** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation 321 ** of resources is deferred until all [prepared statements], [BLOB handles], 322 ** and [sqlite3_backup] objects are also destroyed. 323 ** 324 ** ^If an [sqlite3] object is destroyed while a transaction is open, 325 ** the transaction is automatically rolled back. 326 ** 327 ** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)] 328 ** must be either a NULL 329 ** pointer or an [sqlite3] object pointer obtained 330 ** from [sqlite3_open()], [sqlite3_open16()], or 331 ** [sqlite3_open_v2()], and not previously closed. 332 ** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer 333 ** argument is a harmless no-op. 334 */ 335 SQLITE_API int sqlite3_close(sqlite3*); 336 SQLITE_API int sqlite3_close_v2(sqlite3*); 337 338 /* 339 ** The type for a callback function. 340 ** This is legacy and deprecated. It is included for historical 341 ** compatibility and is not documented. 342 */ 343 typedef int (*sqlite3_callback)(void*,int,char**, char**); 344 345 /* 346 ** CAPI3REF: One-Step Query Execution Interface 347 ** METHOD: sqlite3 348 ** 349 ** The sqlite3_exec() interface is a convenience wrapper around 350 ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()], 351 ** that allows an application to run multiple statements of SQL 352 ** without having to use a lot of C code. 353 ** 354 ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded, 355 ** semicolon-separate SQL statements passed into its 2nd argument, 356 ** in the context of the [database connection] passed in as its 1st 357 ** argument. ^If the callback function of the 3rd argument to 358 ** sqlite3_exec() is not NULL, then it is invoked for each result row 359 ** coming out of the evaluated SQL statements. ^The 4th argument to 360 ** sqlite3_exec() is relayed through to the 1st argument of each 361 ** callback invocation. ^If the callback pointer to sqlite3_exec() 362 ** is NULL, then no callback is ever invoked and result rows are 363 ** ignored. 364 ** 365 ** ^If an error occurs while evaluating the SQL statements passed into 366 ** sqlite3_exec(), then execution of the current statement stops and 367 ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec() 368 ** is not NULL then any error message is written into memory obtained 369 ** from [sqlite3_malloc()] and passed back through the 5th parameter. 370 ** To avoid memory leaks, the application should invoke [sqlite3_free()] 371 ** on error message strings returned through the 5th parameter of 372 ** sqlite3_exec() after the error message string is no longer needed. 373 ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors 374 ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to 375 ** NULL before returning. 376 ** 377 ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec() 378 ** routine returns SQLITE_ABORT without invoking the callback again and 379 ** without running any subsequent SQL statements. 380 ** 381 ** ^The 2nd argument to the sqlite3_exec() callback function is the 382 ** number of columns in the result. ^The 3rd argument to the sqlite3_exec() 383 ** callback is an array of pointers to strings obtained as if from 384 ** [sqlite3_column_text()], one for each column. ^If an element of a 385 ** result row is NULL then the corresponding string pointer for the 386 ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the 387 ** sqlite3_exec() callback is an array of pointers to strings where each 388 ** entry represents the name of corresponding result column as obtained 389 ** from [sqlite3_column_name()]. 390 ** 391 ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer 392 ** to an empty string, or a pointer that contains only whitespace and/or 393 ** SQL comments, then no SQL statements are evaluated and the database 394 ** is not changed. 395 ** 396 ** Restrictions: 397 ** 398 ** <ul> 399 ** <li> The application must ensure that the 1st parameter to sqlite3_exec() 400 ** is a valid and open [database connection]. 401 ** <li> The application must not close the [database connection] specified by 402 ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running. 403 ** <li> The application must not modify the SQL statement text passed into 404 ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running. 405 ** </ul> 406 */ 407 SQLITE_API int sqlite3_exec( 408 sqlite3*, /* An open database */ 409 const char *sql, /* SQL to be evaluated */ 410 int (*callback)(void*,int,char**,char**), /* Callback function */ 411 void *, /* 1st argument to callback */ 412 char **errmsg /* Error msg written here */ 413 ); 414 415 /* 416 ** CAPI3REF: Result Codes 417 ** KEYWORDS: {result code definitions} 418 ** 419 ** Many SQLite functions return an integer result code from the set shown 420 ** here in order to indicate success or failure. 421 ** 422 ** New error codes may be added in future versions of SQLite. 423 ** 424 ** See also: [extended result code definitions] 425 */ 426 #define SQLITE_OK 0 /* Successful result */ 427 /* beginning-of-error-codes */ 428 #define SQLITE_ERROR 1 /* Generic error */ 429 #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ 430 #define SQLITE_PERM 3 /* Access permission denied */ 431 #define SQLITE_ABORT 4 /* Callback routine requested an abort */ 432 #define SQLITE_BUSY 5 /* The database file is locked */ 433 #define SQLITE_LOCKED 6 /* A table in the database is locked */ 434 #define SQLITE_NOMEM 7 /* A malloc() failed */ 435 #define SQLITE_READONLY 8 /* Attempt to write a readonly database */ 436 #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ 437 #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ 438 #define SQLITE_CORRUPT 11 /* The database disk image is malformed */ 439 #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */ 440 #define SQLITE_FULL 13 /* Insertion failed because database is full */ 441 #define SQLITE_CANTOPEN 14 /* Unable to open the database file */ 442 #define SQLITE_PROTOCOL 15 /* Database lock protocol error */ 443 #define SQLITE_EMPTY 16 /* Internal use only */ 444 #define SQLITE_SCHEMA 17 /* The database schema changed */ 445 #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ 446 #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ 447 #define SQLITE_MISMATCH 20 /* Data type mismatch */ 448 #define SQLITE_MISUSE 21 /* Library used incorrectly */ 449 #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ 450 #define SQLITE_AUTH 23 /* Authorization denied */ 451 #define SQLITE_FORMAT 24 /* Not used */ 452 #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ 453 #define SQLITE_NOTADB 26 /* File opened that is not a database file */ 454 #define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */ 455 #define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */ 456 #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ 457 #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ 458 /* end-of-error-codes */ 459 460 /* 461 ** CAPI3REF: Extended Result Codes 462 ** KEYWORDS: {extended result code definitions} 463 ** 464 ** In its default configuration, SQLite API routines return one of 30 integer 465 ** [result codes]. However, experience has shown that many of 466 ** these result codes are too coarse-grained. They do not provide as 467 ** much information about problems as programmers might like. In an effort to 468 ** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8] 469 ** and later) include 470 ** support for additional result codes that provide more detailed information 471 ** about errors. These [extended result codes] are enabled or disabled 472 ** on a per database connection basis using the 473 ** [sqlite3_extended_result_codes()] API. Or, the extended code for 474 ** the most recent error can be obtained using 475 ** [sqlite3_extended_errcode()]. 476 */ 477 #define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8)) 478 #define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8)) 479 #define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8)) 480 #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) 481 #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) 482 #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) 483 #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) 484 #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) 485 #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) 486 #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) 487 #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) 488 #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) 489 #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) 490 #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) 491 #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) 492 #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) 493 #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) 494 #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) 495 #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) 496 #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) 497 #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8)) 498 #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8)) 499 #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8)) 500 #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8)) 501 #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8)) 502 #define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8)) 503 #define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8)) 504 #define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8)) 505 #define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8)) 506 #define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8)) 507 #define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8)) 508 #define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8)) 509 #define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8)) 510 #define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<8)) 511 #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8)) 512 #define SQLITE_LOCKED_VTAB (SQLITE_LOCKED | (2<<8)) 513 #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8)) 514 #define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8)) 515 #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8)) 516 #define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8)) 517 #define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8)) 518 #define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8)) 519 #define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */ 520 #define SQLITE_CANTOPEN_SYMLINK (SQLITE_CANTOPEN | (6<<8)) 521 #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) 522 #define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8)) 523 #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) 524 #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) 525 #define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8)) 526 #define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8)) 527 #define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8)) 528 #define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8)) 529 #define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) 530 #define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8)) 531 #define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8)) 532 #define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8)) 533 #define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8)) 534 #define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8)) 535 #define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8)) 536 #define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8)) 537 #define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8)) 538 #define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8)) 539 #define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8)) 540 #define SQLITE_CONSTRAINT_PINNED (SQLITE_CONSTRAINT |(11<<8)) 541 #define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8)) 542 #define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8)) 543 #define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8)) 544 #define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8)) 545 #define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8)) 546 #define SQLITE_OK_SYMLINK (SQLITE_OK | (2<<8)) 547 548 /* 549 ** CAPI3REF: Flags For File Open Operations 550 ** 551 ** These bit values are intended for use in the 552 ** 3rd parameter to the [sqlite3_open_v2()] interface and 553 ** in the 4th parameter to the [sqlite3_vfs.xOpen] method. 554 */ 555 #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ 556 #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ 557 #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ 558 #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ 559 #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ 560 #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ 561 #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ 562 #define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ 563 #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ 564 #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ 565 #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ 566 #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ 567 #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ 568 #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ 569 #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ 570 #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ 571 #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ 572 #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ 573 #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ 574 #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ 575 #define SQLITE_OPEN_NOFOLLOW 0x01000000 /* Ok for sqlite3_open_v2() */ 576 577 /* Reserved: 0x00F00000 */ 578 579 /* 580 ** CAPI3REF: Device Characteristics 581 ** 582 ** The xDeviceCharacteristics method of the [sqlite3_io_methods] 583 ** object returns an integer which is a vector of these 584 ** bit values expressing I/O characteristics of the mass storage 585 ** device that holds the file that the [sqlite3_io_methods] 586 ** refers to. 587 ** 588 ** The SQLITE_IOCAP_ATOMIC property means that all writes of 589 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 590 ** mean that writes of blocks that are nnn bytes in size and 591 ** are aligned to an address which is an integer multiple of 592 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 593 ** that when data is appended to a file, the data is appended 594 ** first then the size of the file is extended, never the other 595 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 596 ** information is written to disk in the same order as calls 597 ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that 598 ** after reboot following a crash or power loss, the only bytes in a 599 ** file that were written at the application level might have changed 600 ** and that adjacent bytes, even bytes within the same sector are 601 ** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 602 ** flag indicates that a file cannot be deleted when open. The 603 ** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on 604 ** read-only media and cannot be changed even by processes with 605 ** elevated privileges. 606 ** 607 ** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying 608 ** filesystem supports doing multiple write operations atomically when those 609 ** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and 610 ** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. 611 */ 612 #define SQLITE_IOCAP_ATOMIC 0x00000001 613 #define SQLITE_IOCAP_ATOMIC512 0x00000002 614 #define SQLITE_IOCAP_ATOMIC1K 0x00000004 615 #define SQLITE_IOCAP_ATOMIC2K 0x00000008 616 #define SQLITE_IOCAP_ATOMIC4K 0x00000010 617 #define SQLITE_IOCAP_ATOMIC8K 0x00000020 618 #define SQLITE_IOCAP_ATOMIC16K 0x00000040 619 #define SQLITE_IOCAP_ATOMIC32K 0x00000080 620 #define SQLITE_IOCAP_ATOMIC64K 0x00000100 621 #define SQLITE_IOCAP_SAFE_APPEND 0x00000200 622 #define SQLITE_IOCAP_SEQUENTIAL 0x00000400 623 #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 624 #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 625 #define SQLITE_IOCAP_IMMUTABLE 0x00002000 626 #define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000 627 628 /* 629 ** CAPI3REF: File Locking Levels 630 ** 631 ** SQLite uses one of these integer values as the second 632 ** argument to calls it makes to the xLock() and xUnlock() methods 633 ** of an [sqlite3_io_methods] object. 634 */ 635 #define SQLITE_LOCK_NONE 0 636 #define SQLITE_LOCK_SHARED 1 637 #define SQLITE_LOCK_RESERVED 2 638 #define SQLITE_LOCK_PENDING 3 639 #define SQLITE_LOCK_EXCLUSIVE 4 640 641 /* 642 ** CAPI3REF: Synchronization Type Flags 643 ** 644 ** When SQLite invokes the xSync() method of an 645 ** [sqlite3_io_methods] object it uses a combination of 646 ** these integer values as the second argument. 647 ** 648 ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the 649 ** sync operation only needs to flush data to mass storage. Inode 650 ** information need not be flushed. If the lower four bits of the flag 651 ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. 652 ** If the lower four bits equal SQLITE_SYNC_FULL, that means 653 ** to use Mac OS X style fullsync instead of fsync(). 654 ** 655 ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags 656 ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL 657 ** settings. The [synchronous pragma] determines when calls to the 658 ** xSync VFS method occur and applies uniformly across all platforms. 659 ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how 660 ** energetic or rigorous or forceful the sync operations are and 661 ** only make a difference on Mac OSX for the default SQLite code. 662 ** (Third-party VFS implementations might also make the distinction 663 ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the 664 ** operating systems natively supported by SQLite, only Mac OSX 665 ** cares about the difference.) 666 */ 667 #define SQLITE_SYNC_NORMAL 0x00002 668 #define SQLITE_SYNC_FULL 0x00003 669 #define SQLITE_SYNC_DATAONLY 0x00010 670 671 /* 672 ** CAPI3REF: OS Interface Open File Handle 673 ** 674 ** An [sqlite3_file] object represents an open file in the 675 ** [sqlite3_vfs | OS interface layer]. Individual OS interface 676 ** implementations will 677 ** want to subclass this object by appending additional fields 678 ** for their own use. The pMethods entry is a pointer to an 679 ** [sqlite3_io_methods] object that defines methods for performing 680 ** I/O operations on the open file. 681 */ 682 typedef struct sqlite3_file sqlite3_file; 683 struct sqlite3_file { 684 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ 685 }; 686 687 /* 688 ** CAPI3REF: OS Interface File Virtual Methods Object 689 ** 690 ** Every file opened by the [sqlite3_vfs.xOpen] method populates an 691 ** [sqlite3_file] object (or, more commonly, a subclass of the 692 ** [sqlite3_file] object) with a pointer to an instance of this object. 693 ** This object defines the methods used to perform various operations 694 ** against the open file represented by the [sqlite3_file] object. 695 ** 696 ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element 697 ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method 698 ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The 699 ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] 700 ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element 701 ** to NULL. 702 ** 703 ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or 704 ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). 705 ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] 706 ** flag may be ORed in to indicate that only the data of the file 707 ** and not its inode needs to be synced. 708 ** 709 ** The integer values to xLock() and xUnlock() are one of 710 ** <ul> 711 ** <li> [SQLITE_LOCK_NONE], 712 ** <li> [SQLITE_LOCK_SHARED], 713 ** <li> [SQLITE_LOCK_RESERVED], 714 ** <li> [SQLITE_LOCK_PENDING], or 715 ** <li> [SQLITE_LOCK_EXCLUSIVE]. 716 ** </ul> 717 ** xLock() increases the lock. xUnlock() decreases the lock. 718 ** The xCheckReservedLock() method checks whether any database connection, 719 ** either in this process or in some other process, is holding a RESERVED, 720 ** PENDING, or EXCLUSIVE lock on the file. It returns true 721 ** if such a lock exists and false otherwise. 722 ** 723 ** The xFileControl() method is a generic interface that allows custom 724 ** VFS implementations to directly control an open file using the 725 ** [sqlite3_file_control()] interface. The second "op" argument is an 726 ** integer opcode. The third argument is a generic pointer intended to 727 ** point to a structure that may contain arguments or space in which to 728 ** write return values. Potential uses for xFileControl() might be 729 ** functions to enable blocking locks with timeouts, to change the 730 ** locking strategy (for example to use dot-file locks), to inquire 731 ** about the status of a lock, or to break stale locks. The SQLite 732 ** core reserves all opcodes less than 100 for its own use. 733 ** A [file control opcodes | list of opcodes] less than 100 is available. 734 ** Applications that define a custom xFileControl method should use opcodes 735 ** greater than 100 to avoid conflicts. VFS implementations should 736 ** return [SQLITE_NOTFOUND] for file control opcodes that they do not 737 ** recognize. 738 ** 739 ** The xSectorSize() method returns the sector size of the 740 ** device that underlies the file. The sector size is the 741 ** minimum write that can be performed without disturbing 742 ** other bytes in the file. The xDeviceCharacteristics() 743 ** method returns a bit vector describing behaviors of the 744 ** underlying device: 745 ** 746 ** <ul> 747 ** <li> [SQLITE_IOCAP_ATOMIC] 748 ** <li> [SQLITE_IOCAP_ATOMIC512] 749 ** <li> [SQLITE_IOCAP_ATOMIC1K] 750 ** <li> [SQLITE_IOCAP_ATOMIC2K] 751 ** <li> [SQLITE_IOCAP_ATOMIC4K] 752 ** <li> [SQLITE_IOCAP_ATOMIC8K] 753 ** <li> [SQLITE_IOCAP_ATOMIC16K] 754 ** <li> [SQLITE_IOCAP_ATOMIC32K] 755 ** <li> [SQLITE_IOCAP_ATOMIC64K] 756 ** <li> [SQLITE_IOCAP_SAFE_APPEND] 757 ** <li> [SQLITE_IOCAP_SEQUENTIAL] 758 ** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN] 759 ** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE] 760 ** <li> [SQLITE_IOCAP_IMMUTABLE] 761 ** <li> [SQLITE_IOCAP_BATCH_ATOMIC] 762 ** </ul> 763 ** 764 ** The SQLITE_IOCAP_ATOMIC property means that all writes of 765 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 766 ** mean that writes of blocks that are nnn bytes in size and 767 ** are aligned to an address which is an integer multiple of 768 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 769 ** that when data is appended to a file, the data is appended 770 ** first then the size of the file is extended, never the other 771 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 772 ** information is written to disk in the same order as calls 773 ** to xWrite(). 774 ** 775 ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill 776 ** in the unread portions of the buffer with zeros. A VFS that 777 ** fails to zero-fill short reads might seem to work. However, 778 ** failure to zero-fill short reads will eventually lead to 779 ** database corruption. 780 */ 781 typedef struct sqlite3_io_methods sqlite3_io_methods; 782 struct sqlite3_io_methods { 783 int iVersion; 784 int (*xClose)(sqlite3_file*); 785 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); 786 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); 787 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); 788 int (*xSync)(sqlite3_file*, int flags); 789 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); 790 int (*xLock)(sqlite3_file*, int); 791 int (*xUnlock)(sqlite3_file*, int); 792 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); 793 int (*xFileControl)(sqlite3_file*, int op, void *pArg); 794 int (*xSectorSize)(sqlite3_file*); 795 int (*xDeviceCharacteristics)(sqlite3_file*); 796 /* Methods above are valid for version 1 */ 797 int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); 798 int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); 799 void (*xShmBarrier)(sqlite3_file*); 800 int (*xShmUnmap)(sqlite3_file*, int deleteFlag); 801 /* Methods above are valid for version 2 */ 802 int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp); 803 int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p); 804 /* Methods above are valid for version 3 */ 805 /* Additional methods may be added in future releases */ 806 }; 807 808 /* 809 ** CAPI3REF: Standard File Control Opcodes 810 ** KEYWORDS: {file control opcodes} {file control opcode} 811 ** 812 ** These integer constants are opcodes for the xFileControl method 813 ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] 814 ** interface. 815 ** 816 ** <ul> 817 ** <li>[[SQLITE_FCNTL_LOCKSTATE]] 818 ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This 819 ** opcode causes the xFileControl method to write the current state of 820 ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], 821 ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) 822 ** into an integer that the pArg argument points to. This capability 823 ** is used during testing and is only available when the SQLITE_TEST 824 ** compile-time option is used. 825 ** 826 ** <li>[[SQLITE_FCNTL_SIZE_HINT]] 827 ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS 828 ** layer a hint of how large the database file will grow to be during the 829 ** current transaction. This hint is not guaranteed to be accurate but it 830 ** is often close. The underlying VFS might choose to preallocate database 831 ** file space based on this hint in order to help writes to the database 832 ** file run faster. 833 ** 834 ** <li>[[SQLITE_FCNTL_SIZE_LIMIT]] 835 ** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that 836 ** implements [sqlite3_deserialize()] to set an upper bound on the size 837 ** of the in-memory database. The argument is a pointer to a [sqlite3_int64]. 838 ** If the integer pointed to is negative, then it is filled in with the 839 ** current limit. Otherwise the limit is set to the larger of the value 840 ** of the integer pointed to and the current database size. The integer 841 ** pointed to is set to the new limit. 842 ** 843 ** <li>[[SQLITE_FCNTL_CHUNK_SIZE]] 844 ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS 845 ** extends and truncates the database file in chunks of a size specified 846 ** by the user. The fourth argument to [sqlite3_file_control()] should 847 ** point to an integer (type int) containing the new chunk-size to use 848 ** for the nominated database. Allocating database file space in large 849 ** chunks (say 1MB at a time), may reduce file-system fragmentation and 850 ** improve performance on some systems. 851 ** 852 ** <li>[[SQLITE_FCNTL_FILE_POINTER]] 853 ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer 854 ** to the [sqlite3_file] object associated with a particular database 855 ** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER]. 856 ** 857 ** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]] 858 ** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer 859 ** to the [sqlite3_file] object associated with the journal file (either 860 ** the [rollback journal] or the [write-ahead log]) for a particular database 861 ** connection. See also [SQLITE_FCNTL_FILE_POINTER]. 862 ** 863 ** <li>[[SQLITE_FCNTL_SYNC_OMITTED]] 864 ** No longer in use. 865 ** 866 ** <li>[[SQLITE_FCNTL_SYNC]] 867 ** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and 868 ** sent to the VFS immediately before the xSync method is invoked on a 869 ** database file descriptor. Or, if the xSync method is not invoked 870 ** because the user has configured SQLite with 871 ** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place 872 ** of the xSync method. In most cases, the pointer argument passed with 873 ** this file-control is NULL. However, if the database file is being synced 874 ** as part of a multi-database commit, the argument points to a nul-terminated 875 ** string containing the transactions master-journal file name. VFSes that 876 ** do not need this signal should silently ignore this opcode. Applications 877 ** should not call [sqlite3_file_control()] with this opcode as doing so may 878 ** disrupt the operation of the specialized VFSes that do require it. 879 ** 880 ** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]] 881 ** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite 882 ** and sent to the VFS after a transaction has been committed immediately 883 ** but before the database is unlocked. VFSes that do not need this signal 884 ** should silently ignore this opcode. Applications should not call 885 ** [sqlite3_file_control()] with this opcode as doing so may disrupt the 886 ** operation of the specialized VFSes that do require it. 887 ** 888 ** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]] 889 ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic 890 ** retry counts and intervals for certain disk I/O operations for the 891 ** windows [VFS] in order to provide robustness in the presence of 892 ** anti-virus programs. By default, the windows VFS will retry file read, 893 ** file write, and file delete operations up to 10 times, with a delay 894 ** of 25 milliseconds before the first retry and with the delay increasing 895 ** by an additional 25 milliseconds with each subsequent retry. This 896 ** opcode allows these two values (10 retries and 25 milliseconds of delay) 897 ** to be adjusted. The values are changed for all database connections 898 ** within the same process. The argument is a pointer to an array of two 899 ** integers where the first integer is the new retry count and the second 900 ** integer is the delay. If either integer is negative, then the setting 901 ** is not changed but instead the prior value of that setting is written 902 ** into the array entry, allowing the current retry settings to be 903 ** interrogated. The zDbName parameter is ignored. 904 ** 905 ** <li>[[SQLITE_FCNTL_PERSIST_WAL]] 906 ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the 907 ** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary 908 ** write ahead log ([WAL file]) and shared memory 909 ** files used for transaction control 910 ** are automatically deleted when the latest connection to the database 911 ** closes. Setting persistent WAL mode causes those files to persist after 912 ** close. Persisting the files is useful when other processes that do not 913 ** have write permission on the directory containing the database file want 914 ** to read the database file, as the WAL and shared memory files must exist 915 ** in order for the database to be readable. The fourth parameter to 916 ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 917 ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent 918 ** WAL mode. If the integer is -1, then it is overwritten with the current 919 ** WAL persistence setting. 920 ** 921 ** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]] 922 ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the 923 ** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting 924 ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the 925 ** xDeviceCharacteristics methods. The fourth parameter to 926 ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 927 ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage 928 ** mode. If the integer is -1, then it is overwritten with the current 929 ** zero-damage mode setting. 930 ** 931 ** <li>[[SQLITE_FCNTL_OVERWRITE]] 932 ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening 933 ** a write transaction to indicate that, unless it is rolled back for some 934 ** reason, the entire database file will be overwritten by the current 935 ** transaction. This is used by VACUUM operations. 936 ** 937 ** <li>[[SQLITE_FCNTL_VFSNAME]] 938 ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of 939 ** all [VFSes] in the VFS stack. The names are of all VFS shims and the 940 ** final bottom-level VFS are written into memory obtained from 941 ** [sqlite3_malloc()] and the result is stored in the char* variable 942 ** that the fourth parameter of [sqlite3_file_control()] points to. 943 ** The caller is responsible for freeing the memory when done. As with 944 ** all file-control actions, there is no guarantee that this will actually 945 ** do anything. Callers should initialize the char* variable to a NULL 946 ** pointer in case this file-control is not implemented. This file-control 947 ** is intended for diagnostic use only. 948 ** 949 ** <li>[[SQLITE_FCNTL_VFS_POINTER]] 950 ** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level 951 ** [VFSes] currently in use. ^(The argument X in 952 ** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be 953 ** of type "[sqlite3_vfs] **". This opcodes will set *X 954 ** to a pointer to the top-level VFS.)^ 955 ** ^When there are multiple VFS shims in the stack, this opcode finds the 956 ** upper-most shim only. 957 ** 958 ** <li>[[SQLITE_FCNTL_PRAGMA]] 959 ** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] 960 ** file control is sent to the open [sqlite3_file] object corresponding 961 ** to the database file to which the pragma statement refers. ^The argument 962 ** to the [SQLITE_FCNTL_PRAGMA] file control is an array of 963 ** pointers to strings (char**) in which the second element of the array 964 ** is the name of the pragma and the third element is the argument to the 965 ** pragma or NULL if the pragma has no argument. ^The handler for an 966 ** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element 967 ** of the char** argument point to a string obtained from [sqlite3_mprintf()] 968 ** or the equivalent and that string will become the result of the pragma or 969 ** the error message if the pragma fails. ^If the 970 ** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal 971 ** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA] 972 ** file control returns [SQLITE_OK], then the parser assumes that the 973 ** VFS has handled the PRAGMA itself and the parser generates a no-op 974 ** prepared statement if result string is NULL, or that returns a copy 975 ** of the result string if the string is non-NULL. 976 ** ^If the [SQLITE_FCNTL_PRAGMA] file control returns 977 ** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means 978 ** that the VFS encountered an error while handling the [PRAGMA] and the 979 ** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA] 980 ** file control occurs at the beginning of pragma statement analysis and so 981 ** it is able to override built-in [PRAGMA] statements. 982 ** 983 ** <li>[[SQLITE_FCNTL_BUSYHANDLER]] 984 ** ^The [SQLITE_FCNTL_BUSYHANDLER] 985 ** file-control may be invoked by SQLite on the database file handle 986 ** shortly after it is opened in order to provide a custom VFS with access 987 ** to the connection's busy-handler callback. The argument is of type (void**) 988 ** - an array of two (void *) values. The first (void *) actually points 989 ** to a function of type (int (*)(void *)). In order to invoke the connection's 990 ** busy-handler, this function should be invoked with the second (void *) in 991 ** the array as the only argument. If it returns non-zero, then the operation 992 ** should be retried. If it returns zero, the custom VFS should abandon the 993 ** current operation. 994 ** 995 ** <li>[[SQLITE_FCNTL_TEMPFILENAME]] 996 ** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control 997 ** to have SQLite generate a 998 ** temporary filename using the same algorithm that is followed to generate 999 ** temporary filenames for TEMP tables and other internal uses. The 1000 ** argument should be a char** which will be filled with the filename 1001 ** written into memory obtained from [sqlite3_malloc()]. The caller should 1002 ** invoke [sqlite3_free()] on the result to avoid a memory leak. 1003 ** 1004 ** <li>[[SQLITE_FCNTL_MMAP_SIZE]] 1005 ** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the 1006 ** maximum number of bytes that will be used for memory-mapped I/O. 1007 ** The argument is a pointer to a value of type sqlite3_int64 that 1008 ** is an advisory maximum number of bytes in the file to memory map. The 1009 ** pointer is overwritten with the old value. The limit is not changed if 1010 ** the value originally pointed to is negative, and so the current limit 1011 ** can be queried by passing in a pointer to a negative number. This 1012 ** file-control is used internally to implement [PRAGMA mmap_size]. 1013 ** 1014 ** <li>[[SQLITE_FCNTL_TRACE]] 1015 ** The [SQLITE_FCNTL_TRACE] file control provides advisory information 1016 ** to the VFS about what the higher layers of the SQLite stack are doing. 1017 ** This file control is used by some VFS activity tracing [shims]. 1018 ** The argument is a zero-terminated string. Higher layers in the 1019 ** SQLite stack may generate instances of this file control if 1020 ** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled. 1021 ** 1022 ** <li>[[SQLITE_FCNTL_HAS_MOVED]] 1023 ** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a 1024 ** pointer to an integer and it writes a boolean into that integer depending 1025 ** on whether or not the file has been renamed, moved, or deleted since it 1026 ** was first opened. 1027 ** 1028 ** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]] 1029 ** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the 1030 ** underlying native file handle associated with a file handle. This file 1031 ** control interprets its argument as a pointer to a native file handle and 1032 ** writes the resulting value there. 1033 ** 1034 ** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]] 1035 ** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This 1036 ** opcode causes the xFileControl method to swap the file handle with the one 1037 ** pointed to by the pArg argument. This capability is used during testing 1038 ** and only needs to be supported when SQLITE_TEST is defined. 1039 ** 1040 ** <li>[[SQLITE_FCNTL_WAL_BLOCK]] 1041 ** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might 1042 ** be advantageous to block on the next WAL lock if the lock is not immediately 1043 ** available. The WAL subsystem issues this signal during rare 1044 ** circumstances in order to fix a problem with priority inversion. 1045 ** Applications should <em>not</em> use this file-control. 1046 ** 1047 ** <li>[[SQLITE_FCNTL_ZIPVFS]] 1048 ** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other 1049 ** VFS should return SQLITE_NOTFOUND for this opcode. 1050 ** 1051 ** <li>[[SQLITE_FCNTL_RBU]] 1052 ** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by 1053 ** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for 1054 ** this opcode. 1055 ** 1056 ** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]] 1057 ** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then 1058 ** the file descriptor is placed in "batch write mode", which 1059 ** means all subsequent write operations will be deferred and done 1060 ** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems 1061 ** that do not support batch atomic writes will return SQLITE_NOTFOUND. 1062 ** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to 1063 ** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or 1064 ** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make 1065 ** no VFS interface calls on the same [sqlite3_file] file descriptor 1066 ** except for calls to the xWrite method and the xFileControl method 1067 ** with [SQLITE_FCNTL_SIZE_HINT]. 1068 ** 1069 ** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]] 1070 ** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write 1071 ** operations since the previous successful call to 1072 ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically. 1073 ** This file control returns [SQLITE_OK] if and only if the writes were 1074 ** all performed successfully and have been committed to persistent storage. 1075 ** ^Regardless of whether or not it is successful, this file control takes 1076 ** the file descriptor out of batch write mode so that all subsequent 1077 ** write operations are independent. 1078 ** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without 1079 ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1080 ** 1081 ** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]] 1082 ** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write 1083 ** operations since the previous successful call to 1084 ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back. 1085 ** ^This file control takes the file descriptor out of batch write mode 1086 ** so that all subsequent write operations are independent. 1087 ** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without 1088 ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1089 ** 1090 ** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]] 1091 ** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode causes attempts to obtain 1092 ** a file lock using the xLock or xShmLock methods of the VFS to wait 1093 ** for up to M milliseconds before failing, where M is the single 1094 ** unsigned integer parameter. 1095 ** 1096 ** <li>[[SQLITE_FCNTL_DATA_VERSION]] 1097 ** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to 1098 ** a database file. The argument is a pointer to a 32-bit unsigned integer. 1099 ** The "data version" for the pager is written into the pointer. The 1100 ** "data version" changes whenever any change occurs to the corresponding 1101 ** database file, either through SQL statements on the same database 1102 ** connection or through transactions committed by separate database 1103 ** connections possibly in other processes. The [sqlite3_total_changes()] 1104 ** interface can be used to find if any database on the connection has changed, 1105 ** but that interface responds to changes on TEMP as well as MAIN and does 1106 ** not provide a mechanism to detect changes to MAIN only. Also, the 1107 ** [sqlite3_total_changes()] interface responds to internal changes only and 1108 ** omits changes made by other database connections. The 1109 ** [PRAGMA data_version] command provides a mechanism to detect changes to 1110 ** a single attached database that occur due to other database connections, 1111 ** but omits changes implemented by the database connection on which it is 1112 ** called. This file control is the only mechanism to detect changes that 1113 ** happen either internally or externally and that are associated with 1114 ** a particular attached database. 1115 ** 1116 ** <li>[[SQLITE_FCNTL_CKPT_DONE]] 1117 ** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint 1118 ** in wal mode after the client has finished copying pages from the wal 1119 ** file to the database file, but before the *-shm file is updated to 1120 ** record the fact that the pages have been checkpointed. 1121 ** </ul> 1122 */ 1123 #define SQLITE_FCNTL_LOCKSTATE 1 1124 #define SQLITE_FCNTL_GET_LOCKPROXYFILE 2 1125 #define SQLITE_FCNTL_SET_LOCKPROXYFILE 3 1126 #define SQLITE_FCNTL_LAST_ERRNO 4 1127 #define SQLITE_FCNTL_SIZE_HINT 5 1128 #define SQLITE_FCNTL_CHUNK_SIZE 6 1129 #define SQLITE_FCNTL_FILE_POINTER 7 1130 #define SQLITE_FCNTL_SYNC_OMITTED 8 1131 #define SQLITE_FCNTL_WIN32_AV_RETRY 9 1132 #define SQLITE_FCNTL_PERSIST_WAL 10 1133 #define SQLITE_FCNTL_OVERWRITE 11 1134 #define SQLITE_FCNTL_VFSNAME 12 1135 #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 1136 #define SQLITE_FCNTL_PRAGMA 14 1137 #define SQLITE_FCNTL_BUSYHANDLER 15 1138 #define SQLITE_FCNTL_TEMPFILENAME 16 1139 #define SQLITE_FCNTL_MMAP_SIZE 18 1140 #define SQLITE_FCNTL_TRACE 19 1141 #define SQLITE_FCNTL_HAS_MOVED 20 1142 #define SQLITE_FCNTL_SYNC 21 1143 #define SQLITE_FCNTL_COMMIT_PHASETWO 22 1144 #define SQLITE_FCNTL_WIN32_SET_HANDLE 23 1145 #define SQLITE_FCNTL_WAL_BLOCK 24 1146 #define SQLITE_FCNTL_ZIPVFS 25 1147 #define SQLITE_FCNTL_RBU 26 1148 #define SQLITE_FCNTL_VFS_POINTER 27 1149 #define SQLITE_FCNTL_JOURNAL_POINTER 28 1150 #define SQLITE_FCNTL_WIN32_GET_HANDLE 29 1151 #define SQLITE_FCNTL_PDB 30 1152 #define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31 1153 #define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32 1154 #define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33 1155 #define SQLITE_FCNTL_LOCK_TIMEOUT 34 1156 #define SQLITE_FCNTL_DATA_VERSION 35 1157 #define SQLITE_FCNTL_SIZE_LIMIT 36 1158 #define SQLITE_FCNTL_CKPT_DONE 37 1159 1160 /* deprecated names */ 1161 #define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE 1162 #define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE 1163 #define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO 1164 1165 1166 /* 1167 ** CAPI3REF: Mutex Handle 1168 ** 1169 ** The mutex module within SQLite defines [sqlite3_mutex] to be an 1170 ** abstract type for a mutex object. The SQLite core never looks 1171 ** at the internal representation of an [sqlite3_mutex]. It only 1172 ** deals with pointers to the [sqlite3_mutex] object. 1173 ** 1174 ** Mutexes are created using [sqlite3_mutex_alloc()]. 1175 */ 1176 typedef struct sqlite3_mutex sqlite3_mutex; 1177 1178 /* 1179 ** CAPI3REF: Loadable Extension Thunk 1180 ** 1181 ** A pointer to the opaque sqlite3_api_routines structure is passed as 1182 ** the third parameter to entry points of [loadable extensions]. This 1183 ** structure must be typedefed in order to work around compiler warnings 1184 ** on some platforms. 1185 */ 1186 typedef struct sqlite3_api_routines sqlite3_api_routines; 1187 1188 /* 1189 ** CAPI3REF: OS Interface Object 1190 ** 1191 ** An instance of the sqlite3_vfs object defines the interface between 1192 ** the SQLite core and the underlying operating system. The "vfs" 1193 ** in the name of the object stands for "virtual file system". See 1194 ** the [VFS | VFS documentation] for further information. 1195 ** 1196 ** The VFS interface is sometimes extended by adding new methods onto 1197 ** the end. Each time such an extension occurs, the iVersion field 1198 ** is incremented. The iVersion value started out as 1 in 1199 ** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2 1200 ** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased 1201 ** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields 1202 ** may be appended to the sqlite3_vfs object and the iVersion value 1203 ** may increase again in future versions of SQLite. 1204 ** Note that due to an oversight, the structure 1205 ** of the sqlite3_vfs object changed in the transition from 1206 ** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0] 1207 ** and yet the iVersion field was not increased. 1208 ** 1209 ** The szOsFile field is the size of the subclassed [sqlite3_file] 1210 ** structure used by this VFS. mxPathname is the maximum length of 1211 ** a pathname in this VFS. 1212 ** 1213 ** Registered sqlite3_vfs objects are kept on a linked list formed by 1214 ** the pNext pointer. The [sqlite3_vfs_register()] 1215 ** and [sqlite3_vfs_unregister()] interfaces manage this list 1216 ** in a thread-safe way. The [sqlite3_vfs_find()] interface 1217 ** searches the list. Neither the application code nor the VFS 1218 ** implementation should use the pNext pointer. 1219 ** 1220 ** The pNext field is the only field in the sqlite3_vfs 1221 ** structure that SQLite will ever modify. SQLite will only access 1222 ** or modify this field while holding a particular static mutex. 1223 ** The application should never modify anything within the sqlite3_vfs 1224 ** object once the object has been registered. 1225 ** 1226 ** The zName field holds the name of the VFS module. The name must 1227 ** be unique across all VFS modules. 1228 ** 1229 ** [[sqlite3_vfs.xOpen]] 1230 ** ^SQLite guarantees that the zFilename parameter to xOpen 1231 ** is either a NULL pointer or string obtained 1232 ** from xFullPathname() with an optional suffix added. 1233 ** ^If a suffix is added to the zFilename parameter, it will 1234 ** consist of a single "-" character followed by no more than 1235 ** 11 alphanumeric and/or "-" characters. 1236 ** ^SQLite further guarantees that 1237 ** the string will be valid and unchanged until xClose() is 1238 ** called. Because of the previous sentence, 1239 ** the [sqlite3_file] can safely store a pointer to the 1240 ** filename if it needs to remember the filename for some reason. 1241 ** If the zFilename parameter to xOpen is a NULL pointer then xOpen 1242 ** must invent its own temporary name for the file. ^Whenever the 1243 ** xFilename parameter is NULL it will also be the case that the 1244 ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. 1245 ** 1246 ** The flags argument to xOpen() includes all bits set in 1247 ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] 1248 ** or [sqlite3_open16()] is used, then flags includes at least 1249 ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 1250 ** If xOpen() opens a file read-only then it sets *pOutFlags to 1251 ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. 1252 ** 1253 ** ^(SQLite will also add one of the following flags to the xOpen() 1254 ** call, depending on the object being opened: 1255 ** 1256 ** <ul> 1257 ** <li> [SQLITE_OPEN_MAIN_DB] 1258 ** <li> [SQLITE_OPEN_MAIN_JOURNAL] 1259 ** <li> [SQLITE_OPEN_TEMP_DB] 1260 ** <li> [SQLITE_OPEN_TEMP_JOURNAL] 1261 ** <li> [SQLITE_OPEN_TRANSIENT_DB] 1262 ** <li> [SQLITE_OPEN_SUBJOURNAL] 1263 ** <li> [SQLITE_OPEN_MASTER_JOURNAL] 1264 ** <li> [SQLITE_OPEN_WAL] 1265 ** </ul>)^ 1266 ** 1267 ** The file I/O implementation can use the object type flags to 1268 ** change the way it deals with files. For example, an application 1269 ** that does not care about crash recovery or rollback might make 1270 ** the open of a journal file a no-op. Writes to this journal would 1271 ** also be no-ops, and any attempt to read the journal would return 1272 ** SQLITE_IOERR. Or the implementation might recognize that a database 1273 ** file will be doing page-aligned sector reads and writes in a random 1274 ** order and set up its I/O subsystem accordingly. 1275 ** 1276 ** SQLite might also add one of the following flags to the xOpen method: 1277 ** 1278 ** <ul> 1279 ** <li> [SQLITE_OPEN_DELETEONCLOSE] 1280 ** <li> [SQLITE_OPEN_EXCLUSIVE] 1281 ** </ul> 1282 ** 1283 ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be 1284 ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] 1285 ** will be set for TEMP databases and their journals, transient 1286 ** databases, and subjournals. 1287 ** 1288 ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction 1289 ** with the [SQLITE_OPEN_CREATE] flag, which are both directly 1290 ** analogous to the O_EXCL and O_CREAT flags of the POSIX open() 1291 ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 1292 ** SQLITE_OPEN_CREATE, is used to indicate that file should always 1293 ** be created, and that it is an error if it already exists. 1294 ** It is <i>not</i> used to indicate the file should be opened 1295 ** for exclusive access. 1296 ** 1297 ** ^At least szOsFile bytes of memory are allocated by SQLite 1298 ** to hold the [sqlite3_file] structure passed as the third 1299 ** argument to xOpen. The xOpen method does not have to 1300 ** allocate the structure; it should just fill it in. Note that 1301 ** the xOpen method must set the sqlite3_file.pMethods to either 1302 ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do 1303 ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods 1304 ** element will be valid after xOpen returns regardless of the success 1305 ** or failure of the xOpen call. 1306 ** 1307 ** [[sqlite3_vfs.xAccess]] 1308 ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] 1309 ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to 1310 ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] 1311 ** to test whether a file is at least readable. The SQLITE_ACCESS_READ 1312 ** flag is never actually used and is not implemented in the built-in 1313 ** VFSes of SQLite. The file is named by the second argument and can be a 1314 ** directory. The xAccess method returns [SQLITE_OK] on success or some 1315 ** non-zero error code if there is an I/O error or if the name of 1316 ** the file given in the second argument is illegal. If SQLITE_OK 1317 ** is returned, then non-zero or zero is written into *pResOut to indicate 1318 ** whether or not the file is accessible. 1319 ** 1320 ** ^SQLite will always allocate at least mxPathname+1 bytes for the 1321 ** output buffer xFullPathname. The exact size of the output buffer 1322 ** is also passed as a parameter to both methods. If the output buffer 1323 ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is 1324 ** handled as a fatal error by SQLite, vfs implementations should endeavor 1325 ** to prevent this by setting mxPathname to a sufficiently large value. 1326 ** 1327 ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() 1328 ** interfaces are not strictly a part of the filesystem, but they are 1329 ** included in the VFS structure for completeness. 1330 ** The xRandomness() function attempts to return nBytes bytes 1331 ** of good-quality randomness into zOut. The return value is 1332 ** the actual number of bytes of randomness obtained. 1333 ** The xSleep() method causes the calling thread to sleep for at 1334 ** least the number of microseconds given. ^The xCurrentTime() 1335 ** method returns a Julian Day Number for the current date and time as 1336 ** a floating point value. 1337 ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian 1338 ** Day Number multiplied by 86400000 (the number of milliseconds in 1339 ** a 24-hour day). 1340 ** ^SQLite will use the xCurrentTimeInt64() method to get the current 1341 ** date and time if that method is available (if iVersion is 2 or 1342 ** greater and the function pointer is not NULL) and will fall back 1343 ** to xCurrentTime() if xCurrentTimeInt64() is unavailable. 1344 ** 1345 ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces 1346 ** are not used by the SQLite core. These optional interfaces are provided 1347 ** by some VFSes to facilitate testing of the VFS code. By overriding 1348 ** system calls with functions under its control, a test program can 1349 ** simulate faults and error conditions that would otherwise be difficult 1350 ** or impossible to induce. The set of system calls that can be overridden 1351 ** varies from one VFS to another, and from one version of the same VFS to the 1352 ** next. Applications that use these interfaces must be prepared for any 1353 ** or all of these interfaces to be NULL or for their behavior to change 1354 ** from one release to the next. Applications must not attempt to access 1355 ** any of these methods if the iVersion of the VFS is less than 3. 1356 */ 1357 typedef struct sqlite3_vfs sqlite3_vfs; 1358 typedef void (*sqlite3_syscall_ptr)(void); 1359 struct sqlite3_vfs { 1360 int iVersion; /* Structure version number (currently 3) */ 1361 int szOsFile; /* Size of subclassed sqlite3_file */ 1362 int mxPathname; /* Maximum file pathname length */ 1363 sqlite3_vfs *pNext; /* Next registered VFS */ 1364 const char *zName; /* Name of this virtual file system */ 1365 void *pAppData; /* Pointer to application-specific data */ 1366 int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*, 1367 int flags, int *pOutFlags); 1368 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); 1369 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); 1370 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); 1371 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); 1372 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); 1373 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); 1374 void (*xDlClose)(sqlite3_vfs*, void*); 1375 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); 1376 int (*xSleep)(sqlite3_vfs*, int microseconds); 1377 int (*xCurrentTime)(sqlite3_vfs*, double*); 1378 int (*xGetLastError)(sqlite3_vfs*, int, char *); 1379 /* 1380 ** The methods above are in version 1 of the sqlite_vfs object 1381 ** definition. Those that follow are added in version 2 or later 1382 */ 1383 int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); 1384 /* 1385 ** The methods above are in versions 1 and 2 of the sqlite_vfs object. 1386 ** Those below are for version 3 and greater. 1387 */ 1388 int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); 1389 sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); 1390 const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); 1391 /* 1392 ** The methods above are in versions 1 through 3 of the sqlite_vfs object. 1393 ** New fields may be appended in future versions. The iVersion 1394 ** value will increment whenever this happens. 1395 */ 1396 }; 1397 1398 /* 1399 ** CAPI3REF: Flags for the xAccess VFS method 1400 ** 1401 ** These integer constants can be used as the third parameter to 1402 ** the xAccess method of an [sqlite3_vfs] object. They determine 1403 ** what kind of permissions the xAccess method is looking for. 1404 ** With SQLITE_ACCESS_EXISTS, the xAccess method 1405 ** simply checks whether the file exists. 1406 ** With SQLITE_ACCESS_READWRITE, the xAccess method 1407 ** checks whether the named directory is both readable and writable 1408 ** (in other words, if files can be added, removed, and renamed within 1409 ** the directory). 1410 ** The SQLITE_ACCESS_READWRITE constant is currently used only by the 1411 ** [temp_store_directory pragma], though this could change in a future 1412 ** release of SQLite. 1413 ** With SQLITE_ACCESS_READ, the xAccess method 1414 ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is 1415 ** currently unused, though it might be used in a future release of 1416 ** SQLite. 1417 */ 1418 #define SQLITE_ACCESS_EXISTS 0 1419 #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ 1420 #define SQLITE_ACCESS_READ 2 /* Unused */ 1421 1422 /* 1423 ** CAPI3REF: Flags for the xShmLock VFS method 1424 ** 1425 ** These integer constants define the various locking operations 1426 ** allowed by the xShmLock method of [sqlite3_io_methods]. The 1427 ** following are the only legal combinations of flags to the 1428 ** xShmLock method: 1429 ** 1430 ** <ul> 1431 ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED 1432 ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE 1433 ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED 1434 ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE 1435 ** </ul> 1436 ** 1437 ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as 1438 ** was given on the corresponding lock. 1439 ** 1440 ** The xShmLock method can transition between unlocked and SHARED or 1441 ** between unlocked and EXCLUSIVE. It cannot transition between SHARED 1442 ** and EXCLUSIVE. 1443 */ 1444 #define SQLITE_SHM_UNLOCK 1 1445 #define SQLITE_SHM_LOCK 2 1446 #define SQLITE_SHM_SHARED 4 1447 #define SQLITE_SHM_EXCLUSIVE 8 1448 1449 /* 1450 ** CAPI3REF: Maximum xShmLock index 1451 ** 1452 ** The xShmLock method on [sqlite3_io_methods] may use values 1453 ** between 0 and this upper bound as its "offset" argument. 1454 ** The SQLite core will never attempt to acquire or release a 1455 ** lock outside of this range 1456 */ 1457 #define SQLITE_SHM_NLOCK 8 1458 1459 1460 /* 1461 ** CAPI3REF: Initialize The SQLite Library 1462 ** 1463 ** ^The sqlite3_initialize() routine initializes the 1464 ** SQLite library. ^The sqlite3_shutdown() routine 1465 ** deallocates any resources that were allocated by sqlite3_initialize(). 1466 ** These routines are designed to aid in process initialization and 1467 ** shutdown on embedded systems. Workstation applications using 1468 ** SQLite normally do not need to invoke either of these routines. 1469 ** 1470 ** A call to sqlite3_initialize() is an "effective" call if it is 1471 ** the first time sqlite3_initialize() is invoked during the lifetime of 1472 ** the process, or if it is the first time sqlite3_initialize() is invoked 1473 ** following a call to sqlite3_shutdown(). ^(Only an effective call 1474 ** of sqlite3_initialize() does any initialization. All other calls 1475 ** are harmless no-ops.)^ 1476 ** 1477 ** A call to sqlite3_shutdown() is an "effective" call if it is the first 1478 ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only 1479 ** an effective call to sqlite3_shutdown() does any deinitialization. 1480 ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ 1481 ** 1482 ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() 1483 ** is not. The sqlite3_shutdown() interface must only be called from a 1484 ** single thread. All open [database connections] must be closed and all 1485 ** other SQLite resources must be deallocated prior to invoking 1486 ** sqlite3_shutdown(). 1487 ** 1488 ** Among other things, ^sqlite3_initialize() will invoke 1489 ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() 1490 ** will invoke sqlite3_os_end(). 1491 ** 1492 ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. 1493 ** ^If for some reason, sqlite3_initialize() is unable to initialize 1494 ** the library (perhaps it is unable to allocate a needed resource such 1495 ** as a mutex) it returns an [error code] other than [SQLITE_OK]. 1496 ** 1497 ** ^The sqlite3_initialize() routine is called internally by many other 1498 ** SQLite interfaces so that an application usually does not need to 1499 ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] 1500 ** calls sqlite3_initialize() so the SQLite library will be automatically 1501 ** initialized when [sqlite3_open()] is called if it has not be initialized 1502 ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] 1503 ** compile-time option, then the automatic calls to sqlite3_initialize() 1504 ** are omitted and the application must call sqlite3_initialize() directly 1505 ** prior to using any other SQLite interface. For maximum portability, 1506 ** it is recommended that applications always invoke sqlite3_initialize() 1507 ** directly prior to using any other SQLite interface. Future releases 1508 ** of SQLite may require this. In other words, the behavior exhibited 1509 ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the 1510 ** default behavior in some future release of SQLite. 1511 ** 1512 ** The sqlite3_os_init() routine does operating-system specific 1513 ** initialization of the SQLite library. The sqlite3_os_end() 1514 ** routine undoes the effect of sqlite3_os_init(). Typical tasks 1515 ** performed by these routines include allocation or deallocation 1516 ** of static resources, initialization of global variables, 1517 ** setting up a default [sqlite3_vfs] module, or setting up 1518 ** a default configuration using [sqlite3_config()]. 1519 ** 1520 ** The application should never invoke either sqlite3_os_init() 1521 ** or sqlite3_os_end() directly. The application should only invoke 1522 ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() 1523 ** interface is called automatically by sqlite3_initialize() and 1524 ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate 1525 ** implementations for sqlite3_os_init() and sqlite3_os_end() 1526 ** are built into SQLite when it is compiled for Unix, Windows, or OS/2. 1527 ** When [custom builds | built for other platforms] 1528 ** (using the [SQLITE_OS_OTHER=1] compile-time 1529 ** option) the application must supply a suitable implementation for 1530 ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied 1531 ** implementation of sqlite3_os_init() or sqlite3_os_end() 1532 ** must return [SQLITE_OK] on success and some other [error code] upon 1533 ** failure. 1534 */ 1535 SQLITE_API int sqlite3_initialize(void); 1536 SQLITE_API int sqlite3_shutdown(void); 1537 SQLITE_API int sqlite3_os_init(void); 1538 SQLITE_API int sqlite3_os_end(void); 1539 1540 /* 1541 ** CAPI3REF: Configuring The SQLite Library 1542 ** 1543 ** The sqlite3_config() interface is used to make global configuration 1544 ** changes to SQLite in order to tune SQLite to the specific needs of 1545 ** the application. The default configuration is recommended for most 1546 ** applications and so this routine is usually not necessary. It is 1547 ** provided to support rare applications with unusual needs. 1548 ** 1549 ** <b>The sqlite3_config() interface is not threadsafe. The application 1550 ** must ensure that no other SQLite interfaces are invoked by other 1551 ** threads while sqlite3_config() is running.</b> 1552 ** 1553 ** The sqlite3_config() interface 1554 ** may only be invoked prior to library initialization using 1555 ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. 1556 ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before 1557 ** [sqlite3_shutdown()] then it will return SQLITE_MISUSE. 1558 ** Note, however, that ^sqlite3_config() can be called as part of the 1559 ** implementation of an application-defined [sqlite3_os_init()]. 1560 ** 1561 ** The first argument to sqlite3_config() is an integer 1562 ** [configuration option] that determines 1563 ** what property of SQLite is to be configured. Subsequent arguments 1564 ** vary depending on the [configuration option] 1565 ** in the first argument. 1566 ** 1567 ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. 1568 ** ^If the option is unknown or SQLite is unable to set the option 1569 ** then this routine returns a non-zero [error code]. 1570 */ 1571 SQLITE_API int sqlite3_config(int, ...); 1572 1573 /* 1574 ** CAPI3REF: Configure database connections 1575 ** METHOD: sqlite3 1576 ** 1577 ** The sqlite3_db_config() interface is used to make configuration 1578 ** changes to a [database connection]. The interface is similar to 1579 ** [sqlite3_config()] except that the changes apply to a single 1580 ** [database connection] (specified in the first argument). 1581 ** 1582 ** The second argument to sqlite3_db_config(D,V,...) is the 1583 ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code 1584 ** that indicates what aspect of the [database connection] is being configured. 1585 ** Subsequent arguments vary depending on the configuration verb. 1586 ** 1587 ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if 1588 ** the call is considered successful. 1589 */ 1590 SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...); 1591 1592 /* 1593 ** CAPI3REF: Memory Allocation Routines 1594 ** 1595 ** An instance of this object defines the interface between SQLite 1596 ** and low-level memory allocation routines. 1597 ** 1598 ** This object is used in only one place in the SQLite interface. 1599 ** A pointer to an instance of this object is the argument to 1600 ** [sqlite3_config()] when the configuration option is 1601 ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. 1602 ** By creating an instance of this object 1603 ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) 1604 ** during configuration, an application can specify an alternative 1605 ** memory allocation subsystem for SQLite to use for all of its 1606 ** dynamic memory needs. 1607 ** 1608 ** Note that SQLite comes with several [built-in memory allocators] 1609 ** that are perfectly adequate for the overwhelming majority of applications 1610 ** and that this object is only useful to a tiny minority of applications 1611 ** with specialized memory allocation requirements. This object is 1612 ** also used during testing of SQLite in order to specify an alternative 1613 ** memory allocator that simulates memory out-of-memory conditions in 1614 ** order to verify that SQLite recovers gracefully from such 1615 ** conditions. 1616 ** 1617 ** The xMalloc, xRealloc, and xFree methods must work like the 1618 ** malloc(), realloc() and free() functions from the standard C library. 1619 ** ^SQLite guarantees that the second argument to 1620 ** xRealloc is always a value returned by a prior call to xRoundup. 1621 ** 1622 ** xSize should return the allocated size of a memory allocation 1623 ** previously obtained from xMalloc or xRealloc. The allocated size 1624 ** is always at least as big as the requested size but may be larger. 1625 ** 1626 ** The xRoundup method returns what would be the allocated size of 1627 ** a memory allocation given a particular requested size. Most memory 1628 ** allocators round up memory allocations at least to the next multiple 1629 ** of 8. Some allocators round up to a larger multiple or to a power of 2. 1630 ** Every memory allocation request coming in through [sqlite3_malloc()] 1631 ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, 1632 ** that causes the corresponding memory allocation to fail. 1633 ** 1634 ** The xInit method initializes the memory allocator. For example, 1635 ** it might allocate any required mutexes or initialize internal data 1636 ** structures. The xShutdown method is invoked (indirectly) by 1637 ** [sqlite3_shutdown()] and should deallocate any resources acquired 1638 ** by xInit. The pAppData pointer is used as the only parameter to 1639 ** xInit and xShutdown. 1640 ** 1641 ** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes 1642 ** the xInit method, so the xInit method need not be threadsafe. The 1643 ** xShutdown method is only called from [sqlite3_shutdown()] so it does 1644 ** not need to be threadsafe either. For all other methods, SQLite 1645 ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the 1646 ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which 1647 ** it is by default) and so the methods are automatically serialized. 1648 ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other 1649 ** methods must be threadsafe or else make their own arrangements for 1650 ** serialization. 1651 ** 1652 ** SQLite will never invoke xInit() more than once without an intervening 1653 ** call to xShutdown(). 1654 */ 1655 typedef struct sqlite3_mem_methods sqlite3_mem_methods; 1656 struct sqlite3_mem_methods { 1657 void *(*xMalloc)(int); /* Memory allocation function */ 1658 void (*xFree)(void*); /* Free a prior allocation */ 1659 void *(*xRealloc)(void*,int); /* Resize an allocation */ 1660 int (*xSize)(void*); /* Return the size of an allocation */ 1661 int (*xRoundup)(int); /* Round up request size to allocation size */ 1662 int (*xInit)(void*); /* Initialize the memory allocator */ 1663 void (*xShutdown)(void*); /* Deinitialize the memory allocator */ 1664 void *pAppData; /* Argument to xInit() and xShutdown() */ 1665 }; 1666 1667 /* 1668 ** CAPI3REF: Configuration Options 1669 ** KEYWORDS: {configuration option} 1670 ** 1671 ** These constants are the available integer configuration options that 1672 ** can be passed as the first argument to the [sqlite3_config()] interface. 1673 ** 1674 ** New configuration options may be added in future releases of SQLite. 1675 ** Existing configuration options might be discontinued. Applications 1676 ** should check the return code from [sqlite3_config()] to make sure that 1677 ** the call worked. The [sqlite3_config()] interface will return a 1678 ** non-zero [error code] if a discontinued or unsupported configuration option 1679 ** is invoked. 1680 ** 1681 ** <dl> 1682 ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt> 1683 ** <dd>There are no arguments to this option. ^This option sets the 1684 ** [threading mode] to Single-thread. In other words, it disables 1685 ** all mutexing and puts SQLite into a mode where it can only be used 1686 ** by a single thread. ^If SQLite is compiled with 1687 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1688 ** it is not possible to change the [threading mode] from its default 1689 ** value of Single-thread and so [sqlite3_config()] will return 1690 ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD 1691 ** configuration option.</dd> 1692 ** 1693 ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt> 1694 ** <dd>There are no arguments to this option. ^This option sets the 1695 ** [threading mode] to Multi-thread. In other words, it disables 1696 ** mutexing on [database connection] and [prepared statement] objects. 1697 ** The application is responsible for serializing access to 1698 ** [database connections] and [prepared statements]. But other mutexes 1699 ** are enabled so that SQLite will be safe to use in a multi-threaded 1700 ** environment as long as no two threads attempt to use the same 1701 ** [database connection] at the same time. ^If SQLite is compiled with 1702 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1703 ** it is not possible to set the Multi-thread [threading mode] and 1704 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1705 ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd> 1706 ** 1707 ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt> 1708 ** <dd>There are no arguments to this option. ^This option sets the 1709 ** [threading mode] to Serialized. In other words, this option enables 1710 ** all mutexes including the recursive 1711 ** mutexes on [database connection] and [prepared statement] objects. 1712 ** In this mode (which is the default when SQLite is compiled with 1713 ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access 1714 ** to [database connections] and [prepared statements] so that the 1715 ** application is free to use the same [database connection] or the 1716 ** same [prepared statement] in different threads at the same time. 1717 ** ^If SQLite is compiled with 1718 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1719 ** it is not possible to set the Serialized [threading mode] and 1720 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1721 ** SQLITE_CONFIG_SERIALIZED configuration option.</dd> 1722 ** 1723 ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt> 1724 ** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is 1725 ** a pointer to an instance of the [sqlite3_mem_methods] structure. 1726 ** The argument specifies 1727 ** alternative low-level memory allocation routines to be used in place of 1728 ** the memory allocation routines built into SQLite.)^ ^SQLite makes 1729 ** its own private copy of the content of the [sqlite3_mem_methods] structure 1730 ** before the [sqlite3_config()] call returns.</dd> 1731 ** 1732 ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt> 1733 ** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which 1734 ** is a pointer to an instance of the [sqlite3_mem_methods] structure. 1735 ** The [sqlite3_mem_methods] 1736 ** structure is filled with the currently defined memory allocation routines.)^ 1737 ** This option can be used to overload the default memory allocation 1738 ** routines with a wrapper that simulations memory allocation failure or 1739 ** tracks memory usage, for example. </dd> 1740 ** 1741 ** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt> 1742 ** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of 1743 ** type int, interpreted as a boolean, which if true provides a hint to 1744 ** SQLite that it should avoid large memory allocations if possible. 1745 ** SQLite will run faster if it is free to make large memory allocations, 1746 ** but some application might prefer to run slower in exchange for 1747 ** guarantees about memory fragmentation that are possible if large 1748 ** allocations are avoided. This hint is normally off. 1749 ** </dd> 1750 ** 1751 ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt> 1752 ** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int, 1753 ** interpreted as a boolean, which enables or disables the collection of 1754 ** memory allocation statistics. ^(When memory allocation statistics are 1755 ** disabled, the following SQLite interfaces become non-operational: 1756 ** <ul> 1757 ** <li> [sqlite3_hard_heap_limit64()] 1758 ** <li> [sqlite3_memory_used()] 1759 ** <li> [sqlite3_memory_highwater()] 1760 ** <li> [sqlite3_soft_heap_limit64()] 1761 ** <li> [sqlite3_status64()] 1762 ** </ul>)^ 1763 ** ^Memory allocation statistics are enabled by default unless SQLite is 1764 ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory 1765 ** allocation statistics are disabled by default. 1766 ** </dd> 1767 ** 1768 ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt> 1769 ** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used. 1770 ** </dd> 1771 ** 1772 ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt> 1773 ** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool 1774 ** that SQLite can use for the database page cache with the default page 1775 ** cache implementation. 1776 ** This configuration option is a no-op if an application-defined page 1777 ** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2]. 1778 ** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to 1779 ** 8-byte aligned memory (pMem), the size of each page cache line (sz), 1780 ** and the number of cache lines (N). 1781 ** The sz argument should be the size of the largest database page 1782 ** (a power of two between 512 and 65536) plus some extra bytes for each 1783 ** page header. ^The number of extra bytes needed by the page header 1784 ** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ]. 1785 ** ^It is harmless, apart from the wasted memory, 1786 ** for the sz parameter to be larger than necessary. The pMem 1787 ** argument must be either a NULL pointer or a pointer to an 8-byte 1788 ** aligned block of memory of at least sz*N bytes, otherwise 1789 ** subsequent behavior is undefined. 1790 ** ^When pMem is not NULL, SQLite will strive to use the memory provided 1791 ** to satisfy page cache needs, falling back to [sqlite3_malloc()] if 1792 ** a page cache line is larger than sz bytes or if all of the pMem buffer 1793 ** is exhausted. 1794 ** ^If pMem is NULL and N is non-zero, then each database connection 1795 ** does an initial bulk allocation for page cache memory 1796 ** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or 1797 ** of -1024*N bytes if N is negative, . ^If additional 1798 ** page cache memory is needed beyond what is provided by the initial 1799 ** allocation, then SQLite goes to [sqlite3_malloc()] separately for each 1800 ** additional cache line. </dd> 1801 ** 1802 ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt> 1803 ** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer 1804 ** that SQLite will use for all of its dynamic memory allocation needs 1805 ** beyond those provided for by [SQLITE_CONFIG_PAGECACHE]. 1806 ** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled 1807 ** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns 1808 ** [SQLITE_ERROR] if invoked otherwise. 1809 ** ^There are three arguments to SQLITE_CONFIG_HEAP: 1810 ** An 8-byte aligned pointer to the memory, 1811 ** the number of bytes in the memory buffer, and the minimum allocation size. 1812 ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts 1813 ** to using its default memory allocator (the system malloc() implementation), 1814 ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the 1815 ** memory pointer is not NULL then the alternative memory 1816 ** allocator is engaged to handle all of SQLites memory allocation needs. 1817 ** The first pointer (the memory pointer) must be aligned to an 8-byte 1818 ** boundary or subsequent behavior of SQLite will be undefined. 1819 ** The minimum allocation size is capped at 2**12. Reasonable values 1820 ** for the minimum allocation size are 2**5 through 2**8.</dd> 1821 ** 1822 ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt> 1823 ** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a 1824 ** pointer to an instance of the [sqlite3_mutex_methods] structure. 1825 ** The argument specifies alternative low-level mutex routines to be used 1826 ** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of 1827 ** the content of the [sqlite3_mutex_methods] structure before the call to 1828 ** [sqlite3_config()] returns. ^If SQLite is compiled with 1829 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1830 ** the entire mutexing subsystem is omitted from the build and hence calls to 1831 ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will 1832 ** return [SQLITE_ERROR].</dd> 1833 ** 1834 ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt> 1835 ** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which 1836 ** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The 1837 ** [sqlite3_mutex_methods] 1838 ** structure is filled with the currently defined mutex routines.)^ 1839 ** This option can be used to overload the default mutex allocation 1840 ** routines with a wrapper used to track mutex usage for performance 1841 ** profiling or testing, for example. ^If SQLite is compiled with 1842 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1843 ** the entire mutexing subsystem is omitted from the build and hence calls to 1844 ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will 1845 ** return [SQLITE_ERROR].</dd> 1846 ** 1847 ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt> 1848 ** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine 1849 ** the default size of lookaside memory on each [database connection]. 1850 ** The first argument is the 1851 ** size of each lookaside buffer slot and the second is the number of 1852 ** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE 1853 ** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] 1854 ** option to [sqlite3_db_config()] can be used to change the lookaside 1855 ** configuration on individual connections.)^ </dd> 1856 ** 1857 ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt> 1858 ** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is 1859 ** a pointer to an [sqlite3_pcache_methods2] object. This object specifies 1860 ** the interface to a custom page cache implementation.)^ 1861 ** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd> 1862 ** 1863 ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt> 1864 ** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which 1865 ** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of 1866 ** the current page cache implementation into that object.)^ </dd> 1867 ** 1868 ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt> 1869 ** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite 1870 ** global [error log]. 1871 ** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a 1872 ** function with a call signature of void(*)(void*,int,const char*), 1873 ** and a pointer to void. ^If the function pointer is not NULL, it is 1874 ** invoked by [sqlite3_log()] to process each logging event. ^If the 1875 ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. 1876 ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is 1877 ** passed through as the first parameter to the application-defined logger 1878 ** function whenever that function is invoked. ^The second parameter to 1879 ** the logger function is a copy of the first parameter to the corresponding 1880 ** [sqlite3_log()] call and is intended to be a [result code] or an 1881 ** [extended result code]. ^The third parameter passed to the logger is 1882 ** log message after formatting via [sqlite3_snprintf()]. 1883 ** The SQLite logging interface is not reentrant; the logger function 1884 ** supplied by the application must not invoke any SQLite interface. 1885 ** In a multi-threaded application, the application-defined logger 1886 ** function must be threadsafe. </dd> 1887 ** 1888 ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI 1889 ** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int. 1890 ** If non-zero, then URI handling is globally enabled. If the parameter is zero, 1891 ** then URI handling is globally disabled.)^ ^If URI handling is globally 1892 ** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()], 1893 ** [sqlite3_open16()] or 1894 ** specified as part of [ATTACH] commands are interpreted as URIs, regardless 1895 ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database 1896 ** connection is opened. ^If it is globally disabled, filenames are 1897 ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the 1898 ** database connection is opened. ^(By default, URI handling is globally 1899 ** disabled. The default value may be changed by compiling with the 1900 ** [SQLITE_USE_URI] symbol defined.)^ 1901 ** 1902 ** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN 1903 ** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer 1904 ** argument which is interpreted as a boolean in order to enable or disable 1905 ** the use of covering indices for full table scans in the query optimizer. 1906 ** ^The default setting is determined 1907 ** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on" 1908 ** if that compile-time option is omitted. 1909 ** The ability to disable the use of covering indices for full table scans 1910 ** is because some incorrectly coded legacy applications might malfunction 1911 ** when the optimization is enabled. Providing the ability to 1912 ** disable the optimization allows the older, buggy application code to work 1913 ** without change even with newer versions of SQLite. 1914 ** 1915 ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] 1916 ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE 1917 ** <dd> These options are obsolete and should not be used by new code. 1918 ** They are retained for backwards compatibility but are now no-ops. 1919 ** </dd> 1920 ** 1921 ** [[SQLITE_CONFIG_SQLLOG]] 1922 ** <dt>SQLITE_CONFIG_SQLLOG 1923 ** <dd>This option is only available if sqlite is compiled with the 1924 ** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should 1925 ** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). 1926 ** The second should be of type (void*). The callback is invoked by the library 1927 ** in three separate circumstances, identified by the value passed as the 1928 ** fourth parameter. If the fourth parameter is 0, then the database connection 1929 ** passed as the second argument has just been opened. The third argument 1930 ** points to a buffer containing the name of the main database file. If the 1931 ** fourth parameter is 1, then the SQL statement that the third parameter 1932 ** points to has just been executed. Or, if the fourth parameter is 2, then 1933 ** the connection being passed as the second parameter is being closed. The 1934 ** third parameter is passed NULL In this case. An example of using this 1935 ** configuration option can be seen in the "test_sqllog.c" source file in 1936 ** the canonical SQLite source tree.</dd> 1937 ** 1938 ** [[SQLITE_CONFIG_MMAP_SIZE]] 1939 ** <dt>SQLITE_CONFIG_MMAP_SIZE 1940 ** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values 1941 ** that are the default mmap size limit (the default setting for 1942 ** [PRAGMA mmap_size]) and the maximum allowed mmap size limit. 1943 ** ^The default setting can be overridden by each database connection using 1944 ** either the [PRAGMA mmap_size] command, or by using the 1945 ** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size 1946 ** will be silently truncated if necessary so that it does not exceed the 1947 ** compile-time maximum mmap size set by the 1948 ** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^ 1949 ** ^If either argument to this option is negative, then that argument is 1950 ** changed to its compile-time default. 1951 ** 1952 ** [[SQLITE_CONFIG_WIN32_HEAPSIZE]] 1953 ** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE 1954 ** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is 1955 ** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro 1956 ** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value 1957 ** that specifies the maximum size of the created heap. 1958 ** 1959 ** [[SQLITE_CONFIG_PCACHE_HDRSZ]] 1960 ** <dt>SQLITE_CONFIG_PCACHE_HDRSZ 1961 ** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which 1962 ** is a pointer to an integer and writes into that integer the number of extra 1963 ** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE]. 1964 ** The amount of extra space required can change depending on the compiler, 1965 ** target platform, and SQLite version. 1966 ** 1967 ** [[SQLITE_CONFIG_PMASZ]] 1968 ** <dt>SQLITE_CONFIG_PMASZ 1969 ** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which 1970 ** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded 1971 ** sorter to that integer. The default minimum PMA Size is set by the 1972 ** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched 1973 ** to help with sort operations when multithreaded sorting 1974 ** is enabled (using the [PRAGMA threads] command) and the amount of content 1975 ** to be sorted exceeds the page size times the minimum of the 1976 ** [PRAGMA cache_size] setting and this value. 1977 ** 1978 ** [[SQLITE_CONFIG_STMTJRNL_SPILL]] 1979 ** <dt>SQLITE_CONFIG_STMTJRNL_SPILL 1980 ** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which 1981 ** becomes the [statement journal] spill-to-disk threshold. 1982 ** [Statement journals] are held in memory until their size (in bytes) 1983 ** exceeds this threshold, at which point they are written to disk. 1984 ** Or if the threshold is -1, statement journals are always held 1985 ** exclusively in memory. 1986 ** Since many statement journals never become large, setting the spill 1987 ** threshold to a value such as 64KiB can greatly reduce the amount of 1988 ** I/O required to support statement rollback. 1989 ** The default value for this setting is controlled by the 1990 ** [SQLITE_STMTJRNL_SPILL] compile-time option. 1991 ** 1992 ** [[SQLITE_CONFIG_SORTERREF_SIZE]] 1993 ** <dt>SQLITE_CONFIG_SORTERREF_SIZE 1994 ** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter 1995 ** of type (int) - the new value of the sorter-reference size threshold. 1996 ** Usually, when SQLite uses an external sort to order records according 1997 ** to an ORDER BY clause, all fields required by the caller are present in the 1998 ** sorted records. However, if SQLite determines based on the declared type 1999 ** of a table column that its values are likely to be very large - larger 2000 ** than the configured sorter-reference size threshold - then a reference 2001 ** is stored in each sorted record and the required column values loaded 2002 ** from the database as records are returned in sorted order. The default 2003 ** value for this option is to never use this optimization. Specifying a 2004 ** negative value for this option restores the default behaviour. 2005 ** This option is only available if SQLite is compiled with the 2006 ** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option. 2007 ** 2008 ** [[SQLITE_CONFIG_MEMDB_MAXSIZE]] 2009 ** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE 2010 ** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter 2011 ** [sqlite3_int64] parameter which is the default maximum size for an in-memory 2012 ** database created using [sqlite3_deserialize()]. This default maximum 2013 ** size can be adjusted up or down for individual databases using the 2014 ** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this 2015 ** configuration setting is never used, then the default maximum is determined 2016 ** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that 2017 ** compile-time option is not set, then the default maximum is 1073741824. 2018 ** </dl> 2019 */ 2020 #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ 2021 #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ 2022 #define SQLITE_CONFIG_SERIALIZED 3 /* nil */ 2023 #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ 2024 #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ 2025 #define SQLITE_CONFIG_SCRATCH 6 /* No longer used */ 2026 #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ 2027 #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ 2028 #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ 2029 #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ 2030 #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ 2031 /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 2032 #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ 2033 #define SQLITE_CONFIG_PCACHE 14 /* no-op */ 2034 #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ 2035 #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ 2036 #define SQLITE_CONFIG_URI 17 /* int */ 2037 #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ 2038 #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ 2039 #define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ 2040 #define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ 2041 #define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ 2042 #define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ 2043 #define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ 2044 #define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ 2045 #define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */ 2046 #define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */ 2047 #define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */ 2048 #define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */ 2049 2050 /* 2051 ** CAPI3REF: Database Connection Configuration Options 2052 ** 2053 ** These constants are the available integer configuration options that 2054 ** can be passed as the second argument to the [sqlite3_db_config()] interface. 2055 ** 2056 ** New configuration options may be added in future releases of SQLite. 2057 ** Existing configuration options might be discontinued. Applications 2058 ** should check the return code from [sqlite3_db_config()] to make sure that 2059 ** the call worked. ^The [sqlite3_db_config()] interface will return a 2060 ** non-zero [error code] if a discontinued or unsupported configuration option 2061 ** is invoked. 2062 ** 2063 ** <dl> 2064 ** [[SQLITE_DBCONFIG_LOOKASIDE]] 2065 ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> 2066 ** <dd> ^This option takes three additional arguments that determine the 2067 ** [lookaside memory allocator] configuration for the [database connection]. 2068 ** ^The first argument (the third parameter to [sqlite3_db_config()] is a 2069 ** pointer to a memory buffer to use for lookaside memory. 2070 ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb 2071 ** may be NULL in which case SQLite will allocate the 2072 ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the 2073 ** size of each lookaside buffer slot. ^The third argument is the number of 2074 ** slots. The size of the buffer in the first argument must be greater than 2075 ** or equal to the product of the second and third arguments. The buffer 2076 ** must be aligned to an 8-byte boundary. ^If the second argument to 2077 ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally 2078 ** rounded down to the next smaller multiple of 8. ^(The lookaside memory 2079 ** configuration for a database connection can only be changed when that 2080 ** connection is not currently using lookaside memory, or in other words 2081 ** when the "current value" returned by 2082 ** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero. 2083 ** Any attempt to change the lookaside memory configuration when lookaside 2084 ** memory is in use leaves the configuration unchanged and returns 2085 ** [SQLITE_BUSY].)^</dd> 2086 ** 2087 ** [[SQLITE_DBCONFIG_ENABLE_FKEY]] 2088 ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt> 2089 ** <dd> ^This option is used to enable or disable the enforcement of 2090 ** [foreign key constraints]. There should be two additional arguments. 2091 ** The first argument is an integer which is 0 to disable FK enforcement, 2092 ** positive to enable FK enforcement or negative to leave FK enforcement 2093 ** unchanged. The second parameter is a pointer to an integer into which 2094 ** is written 0 or 1 to indicate whether FK enforcement is off or on 2095 ** following this call. The second parameter may be a NULL pointer, in 2096 ** which case the FK enforcement setting is not reported back. </dd> 2097 ** 2098 ** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]] 2099 ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt> 2100 ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers]. 2101 ** There should be two additional arguments. 2102 ** The first argument is an integer which is 0 to disable triggers, 2103 ** positive to enable triggers or negative to leave the setting unchanged. 2104 ** The second parameter is a pointer to an integer into which 2105 ** is written 0 or 1 to indicate whether triggers are disabled or enabled 2106 ** following this call. The second parameter may be a NULL pointer, in 2107 ** which case the trigger setting is not reported back. </dd> 2108 ** 2109 ** [[SQLITE_DBCONFIG_ENABLE_VIEW]] 2110 ** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt> 2111 ** <dd> ^This option is used to enable or disable [CREATE VIEW | views]. 2112 ** There should be two additional arguments. 2113 ** The first argument is an integer which is 0 to disable views, 2114 ** positive to enable views or negative to leave the setting unchanged. 2115 ** The second parameter is a pointer to an integer into which 2116 ** is written 0 or 1 to indicate whether views are disabled or enabled 2117 ** following this call. The second parameter may be a NULL pointer, in 2118 ** which case the view setting is not reported back. </dd> 2119 ** 2120 ** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]] 2121 ** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt> 2122 ** <dd> ^This option is used to enable or disable the 2123 ** [fts3_tokenizer()] function which is part of the 2124 ** [FTS3] full-text search engine extension. 2125 ** There should be two additional arguments. 2126 ** The first argument is an integer which is 0 to disable fts3_tokenizer() or 2127 ** positive to enable fts3_tokenizer() or negative to leave the setting 2128 ** unchanged. 2129 ** The second parameter is a pointer to an integer into which 2130 ** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled 2131 ** following this call. The second parameter may be a NULL pointer, in 2132 ** which case the new setting is not reported back. </dd> 2133 ** 2134 ** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]] 2135 ** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt> 2136 ** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()] 2137 ** interface independently of the [load_extension()] SQL function. 2138 ** The [sqlite3_enable_load_extension()] API enables or disables both the 2139 ** C-API [sqlite3_load_extension()] and the SQL function [load_extension()]. 2140 ** There should be two additional arguments. 2141 ** When the first argument to this interface is 1, then only the C-API is 2142 ** enabled and the SQL function remains disabled. If the first argument to 2143 ** this interface is 0, then both the C-API and the SQL function are disabled. 2144 ** If the first argument is -1, then no changes are made to state of either the 2145 ** C-API or the SQL function. 2146 ** The second parameter is a pointer to an integer into which 2147 ** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface 2148 ** is disabled or enabled following this call. The second parameter may 2149 ** be a NULL pointer, in which case the new setting is not reported back. 2150 ** </dd> 2151 ** 2152 ** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt> 2153 ** <dd> ^This option is used to change the name of the "main" database 2154 ** schema. ^The sole argument is a pointer to a constant UTF8 string 2155 ** which will become the new schema name in place of "main". ^SQLite 2156 ** does not make a copy of the new main schema name string, so the application 2157 ** must ensure that the argument passed into this DBCONFIG option is unchanged 2158 ** until after the database connection closes. 2159 ** </dd> 2160 ** 2161 ** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]] 2162 ** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt> 2163 ** <dd> Usually, when a database in wal mode is closed or detached from a 2164 ** database handle, SQLite checks if this will mean that there are now no 2165 ** connections at all to the database. If so, it performs a checkpoint 2166 ** operation before closing the connection. This option may be used to 2167 ** override this behaviour. The first parameter passed to this operation 2168 ** is an integer - positive to disable checkpoints-on-close, or zero (the 2169 ** default) to enable them, and negative to leave the setting unchanged. 2170 ** The second parameter is a pointer to an integer 2171 ** into which is written 0 or 1 to indicate whether checkpoints-on-close 2172 ** have been disabled - 0 if they are not disabled, 1 if they are. 2173 ** </dd> 2174 ** 2175 ** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt> 2176 ** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates 2177 ** the [query planner stability guarantee] (QPSG). When the QPSG is active, 2178 ** a single SQL query statement will always use the same algorithm regardless 2179 ** of values of [bound parameters].)^ The QPSG disables some query optimizations 2180 ** that look at the values of bound parameters, which can make some queries 2181 ** slower. But the QPSG has the advantage of more predictable behavior. With 2182 ** the QPSG active, SQLite will always use the same query plan in the field as 2183 ** was used during testing in the lab. 2184 ** The first argument to this setting is an integer which is 0 to disable 2185 ** the QPSG, positive to enable QPSG, or negative to leave the setting 2186 ** unchanged. The second parameter is a pointer to an integer into which 2187 ** is written 0 or 1 to indicate whether the QPSG is disabled or enabled 2188 ** following this call. 2189 ** </dd> 2190 ** 2191 ** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt> 2192 ** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not 2193 ** include output for any operations performed by trigger programs. This 2194 ** option is used to set or clear (the default) a flag that governs this 2195 ** behavior. The first parameter passed to this operation is an integer - 2196 ** positive to enable output for trigger programs, or zero to disable it, 2197 ** or negative to leave the setting unchanged. 2198 ** The second parameter is a pointer to an integer into which is written 2199 ** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if 2200 ** it is not disabled, 1 if it is. 2201 ** </dd> 2202 ** 2203 ** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt> 2204 ** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run 2205 ** [VACUUM] in order to reset a database back to an empty database 2206 ** with no schema and no content. The following process works even for 2207 ** a badly corrupted database file: 2208 ** <ol> 2209 ** <li> If the database connection is newly opened, make sure it has read the 2210 ** database schema by preparing then discarding some query against the 2211 ** database, or calling sqlite3_table_column_metadata(), ignoring any 2212 ** errors. This step is only necessary if the application desires to keep 2213 ** the database in WAL mode after the reset if it was in WAL mode before 2214 ** the reset. 2215 ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0); 2216 ** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0); 2217 ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0); 2218 ** </ol> 2219 ** Because resetting a database is destructive and irreversible, the 2220 ** process requires the use of this obscure API and multiple steps to help 2221 ** ensure that it does not happen by accident. 2222 ** 2223 ** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt> 2224 ** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the 2225 ** "defensive" flag for a database connection. When the defensive 2226 ** flag is enabled, language features that allow ordinary SQL to 2227 ** deliberately corrupt the database file are disabled. The disabled 2228 ** features include but are not limited to the following: 2229 ** <ul> 2230 ** <li> The [PRAGMA writable_schema=ON] statement. 2231 ** <li> The [PRAGMA journal_mode=OFF] statement. 2232 ** <li> Writes to the [sqlite_dbpage] virtual table. 2233 ** <li> Direct writes to [shadow tables]. 2234 ** </ul> 2235 ** </dd> 2236 ** 2237 ** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt> 2238 ** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the 2239 ** "writable_schema" flag. This has the same effect and is logically equivalent 2240 ** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF]. 2241 ** The first argument to this setting is an integer which is 0 to disable 2242 ** the writable_schema, positive to enable writable_schema, or negative to 2243 ** leave the setting unchanged. The second parameter is a pointer to an 2244 ** integer into which is written 0 or 1 to indicate whether the writable_schema 2245 ** is enabled or disabled following this call. 2246 ** </dd> 2247 ** 2248 ** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]] 2249 ** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt> 2250 ** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates 2251 ** the legacy behavior of the [ALTER TABLE RENAME] command such it 2252 ** behaves as it did prior to [version 3.24.0] (2018-06-04). See the 2253 ** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for 2254 ** additional information. This feature can also be turned on and off 2255 ** using the [PRAGMA legacy_alter_table] statement. 2256 ** </dd> 2257 ** 2258 ** [[SQLITE_DBCONFIG_DQS_DML]] 2259 ** <dt>SQLITE_DBCONFIG_DQS_DML</td> 2260 ** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates 2261 ** the legacy [double-quoted string literal] misfeature for DML statements 2262 ** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The 2263 ** default value of this setting is determined by the [-DSQLITE_DQS] 2264 ** compile-time option. 2265 ** </dd> 2266 ** 2267 ** [[SQLITE_DBCONFIG_DQS_DDL]] 2268 ** <dt>SQLITE_DBCONFIG_DQS_DDL</td> 2269 ** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates 2270 ** the legacy [double-quoted string literal] misfeature for DDL statements, 2271 ** such as CREATE TABLE and CREATE INDEX. The 2272 ** default value of this setting is determined by the [-DSQLITE_DQS] 2273 ** compile-time option. 2274 ** </dd> 2275 ** 2276 ** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]] 2277 ** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</td> 2278 ** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to 2279 ** assume that database schemas (the contents of the [sqlite_master] tables) 2280 ** are untainted by malicious content. 2281 ** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite 2282 ** takes additional defensive steps to protect the application from harm 2283 ** including: 2284 ** <ul> 2285 ** <li> Prohibit the use of SQL functions inside triggers, views, 2286 ** CHECK constraints, DEFAULT clauses, expression indexes, 2287 ** partial indexes, or generated columns 2288 ** unless those functions are tagged with [SQLITE_INNOCUOUS]. 2289 ** <li> Prohibit the use of virtual tables inside of triggers or views 2290 ** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS]. 2291 ** </ul> 2292 ** This setting defaults to "on" for legacy compatibility, however 2293 ** all applications are advised to turn it off if possible. This setting 2294 ** can also be controlled using the [PRAGMA trusted_schema] statement. 2295 ** </dd> 2296 ** 2297 ** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]] 2298 ** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</td> 2299 ** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates 2300 ** the legacy file format flag. When activated, this flag causes all newly 2301 ** created database file to have a schema format version number (the 4-byte 2302 ** integer found at offset 44 into the database header) of 1. This in turn 2303 ** means that the resulting database file will be readable and writable by 2304 ** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting, 2305 ** newly created databases are generally not understandable by SQLite versions 2306 ** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there 2307 ** is now scarcely any need to generated database files that are compatible 2308 ** all the way back to version 3.0.0, and so this setting is of little 2309 ** practical use, but is provided so that SQLite can continue to claim the 2310 ** ability to generate new database files that are compatible with version 2311 ** 3.0.0. 2312 ** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on, 2313 ** the [VACUUM] command will fail with an obscure error when attempting to 2314 ** process a table with generated columns and a descending index. This is 2315 ** not considered a bug since SQLite versions 3.3.0 and earlier do not support 2316 ** either generated columns or decending indexes. 2317 ** </dd> 2318 ** </dl> 2319 */ 2320 #define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */ 2321 #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ 2322 #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ 2323 #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ 2324 #define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */ 2325 #define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */ 2326 #define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */ 2327 #define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */ 2328 #define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */ 2329 #define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */ 2330 #define SQLITE_DBCONFIG_DEFENSIVE 1010 /* int int* */ 2331 #define SQLITE_DBCONFIG_WRITABLE_SCHEMA 1011 /* int int* */ 2332 #define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE 1012 /* int int* */ 2333 #define SQLITE_DBCONFIG_DQS_DML 1013 /* int int* */ 2334 #define SQLITE_DBCONFIG_DQS_DDL 1014 /* int int* */ 2335 #define SQLITE_DBCONFIG_ENABLE_VIEW 1015 /* int int* */ 2336 #define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT 1016 /* int int* */ 2337 #define SQLITE_DBCONFIG_TRUSTED_SCHEMA 1017 /* int int* */ 2338 #define SQLITE_DBCONFIG_MAX 1017 /* Largest DBCONFIG */ 2339 2340 /* 2341 ** CAPI3REF: Enable Or Disable Extended Result Codes 2342 ** METHOD: sqlite3 2343 ** 2344 ** ^The sqlite3_extended_result_codes() routine enables or disables the 2345 ** [extended result codes] feature of SQLite. ^The extended result 2346 ** codes are disabled by default for historical compatibility. 2347 */ 2348 SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); 2349 2350 /* 2351 ** CAPI3REF: Last Insert Rowid 2352 ** METHOD: sqlite3 2353 ** 2354 ** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables) 2355 ** has a unique 64-bit signed 2356 ** integer key called the [ROWID | "rowid"]. ^The rowid is always available 2357 ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those 2358 ** names are not also used by explicitly declared columns. ^If 2359 ** the table has a column of type [INTEGER PRIMARY KEY] then that column 2360 ** is another alias for the rowid. 2361 ** 2362 ** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of 2363 ** the most recent successful [INSERT] into a rowid table or [virtual table] 2364 ** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not 2365 ** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred 2366 ** on the database connection D, then sqlite3_last_insert_rowid(D) returns 2367 ** zero. 2368 ** 2369 ** As well as being set automatically as rows are inserted into database 2370 ** tables, the value returned by this function may be set explicitly by 2371 ** [sqlite3_set_last_insert_rowid()] 2372 ** 2373 ** Some virtual table implementations may INSERT rows into rowid tables as 2374 ** part of committing a transaction (e.g. to flush data accumulated in memory 2375 ** to disk). In this case subsequent calls to this function return the rowid 2376 ** associated with these internal INSERT operations, which leads to 2377 ** unintuitive results. Virtual table implementations that do write to rowid 2378 ** tables in this way can avoid this problem by restoring the original 2379 ** rowid value using [sqlite3_set_last_insert_rowid()] before returning 2380 ** control to the user. 2381 ** 2382 ** ^(If an [INSERT] occurs within a trigger then this routine will 2383 ** return the [rowid] of the inserted row as long as the trigger is 2384 ** running. Once the trigger program ends, the value returned 2385 ** by this routine reverts to what it was before the trigger was fired.)^ 2386 ** 2387 ** ^An [INSERT] that fails due to a constraint violation is not a 2388 ** successful [INSERT] and does not change the value returned by this 2389 ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, 2390 ** and INSERT OR ABORT make no changes to the return value of this 2391 ** routine when their insertion fails. ^(When INSERT OR REPLACE 2392 ** encounters a constraint violation, it does not fail. The 2393 ** INSERT continues to completion after deleting rows that caused 2394 ** the constraint problem so INSERT OR REPLACE will always change 2395 ** the return value of this interface.)^ 2396 ** 2397 ** ^For the purposes of this routine, an [INSERT] is considered to 2398 ** be successful even if it is subsequently rolled back. 2399 ** 2400 ** This function is accessible to SQL statements via the 2401 ** [last_insert_rowid() SQL function]. 2402 ** 2403 ** If a separate thread performs a new [INSERT] on the same 2404 ** database connection while the [sqlite3_last_insert_rowid()] 2405 ** function is running and thus changes the last insert [rowid], 2406 ** then the value returned by [sqlite3_last_insert_rowid()] is 2407 ** unpredictable and might not equal either the old or the new 2408 ** last insert [rowid]. 2409 */ 2410 SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); 2411 2412 /* 2413 ** CAPI3REF: Set the Last Insert Rowid value. 2414 ** METHOD: sqlite3 2415 ** 2416 ** The sqlite3_set_last_insert_rowid(D, R) method allows the application to 2417 ** set the value returned by calling sqlite3_last_insert_rowid(D) to R 2418 ** without inserting a row into the database. 2419 */ 2420 SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64); 2421 2422 /* 2423 ** CAPI3REF: Count The Number Of Rows Modified 2424 ** METHOD: sqlite3 2425 ** 2426 ** ^This function returns the number of rows modified, inserted or 2427 ** deleted by the most recently completed INSERT, UPDATE or DELETE 2428 ** statement on the database connection specified by the only parameter. 2429 ** ^Executing any other type of SQL statement does not modify the value 2430 ** returned by this function. 2431 ** 2432 ** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are 2433 ** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], 2434 ** [foreign key actions] or [REPLACE] constraint resolution are not counted. 2435 ** 2436 ** Changes to a view that are intercepted by 2437 ** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value 2438 ** returned by sqlite3_changes() immediately after an INSERT, UPDATE or 2439 ** DELETE statement run on a view is always zero. Only changes made to real 2440 ** tables are counted. 2441 ** 2442 ** Things are more complicated if the sqlite3_changes() function is 2443 ** executed while a trigger program is running. This may happen if the 2444 ** program uses the [changes() SQL function], or if some other callback 2445 ** function invokes sqlite3_changes() directly. Essentially: 2446 ** 2447 ** <ul> 2448 ** <li> ^(Before entering a trigger program the value returned by 2449 ** sqlite3_changes() function is saved. After the trigger program 2450 ** has finished, the original value is restored.)^ 2451 ** 2452 ** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE 2453 ** statement sets the value returned by sqlite3_changes() 2454 ** upon completion as normal. Of course, this value will not include 2455 ** any changes performed by sub-triggers, as the sqlite3_changes() 2456 ** value will be saved and restored after each sub-trigger has run.)^ 2457 ** </ul> 2458 ** 2459 ** ^This means that if the changes() SQL function (or similar) is used 2460 ** by the first INSERT, UPDATE or DELETE statement within a trigger, it 2461 ** returns the value as set when the calling statement began executing. 2462 ** ^If it is used by the second or subsequent such statement within a trigger 2463 ** program, the value returned reflects the number of rows modified by the 2464 ** previous INSERT, UPDATE or DELETE statement within the same trigger. 2465 ** 2466 ** If a separate thread makes changes on the same database connection 2467 ** while [sqlite3_changes()] is running then the value returned 2468 ** is unpredictable and not meaningful. 2469 ** 2470 ** See also: 2471 ** <ul> 2472 ** <li> the [sqlite3_total_changes()] interface 2473 ** <li> the [count_changes pragma] 2474 ** <li> the [changes() SQL function] 2475 ** <li> the [data_version pragma] 2476 ** </ul> 2477 */ 2478 SQLITE_API int sqlite3_changes(sqlite3*); 2479 2480 /* 2481 ** CAPI3REF: Total Number Of Rows Modified 2482 ** METHOD: sqlite3 2483 ** 2484 ** ^This function returns the total number of rows inserted, modified or 2485 ** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed 2486 ** since the database connection was opened, including those executed as 2487 ** part of trigger programs. ^Executing any other type of SQL statement 2488 ** does not affect the value returned by sqlite3_total_changes(). 2489 ** 2490 ** ^Changes made as part of [foreign key actions] are included in the 2491 ** count, but those made as part of REPLACE constraint resolution are 2492 ** not. ^Changes to a view that are intercepted by INSTEAD OF triggers 2493 ** are not counted. 2494 ** 2495 ** The [sqlite3_total_changes(D)] interface only reports the number 2496 ** of rows that changed due to SQL statement run against database 2497 ** connection D. Any changes by other database connections are ignored. 2498 ** To detect changes against a database file from other database 2499 ** connections use the [PRAGMA data_version] command or the 2500 ** [SQLITE_FCNTL_DATA_VERSION] [file control]. 2501 ** 2502 ** If a separate thread makes changes on the same database connection 2503 ** while [sqlite3_total_changes()] is running then the value 2504 ** returned is unpredictable and not meaningful. 2505 ** 2506 ** See also: 2507 ** <ul> 2508 ** <li> the [sqlite3_changes()] interface 2509 ** <li> the [count_changes pragma] 2510 ** <li> the [changes() SQL function] 2511 ** <li> the [data_version pragma] 2512 ** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control] 2513 ** </ul> 2514 */ 2515 SQLITE_API int sqlite3_total_changes(sqlite3*); 2516 2517 /* 2518 ** CAPI3REF: Interrupt A Long-Running Query 2519 ** METHOD: sqlite3 2520 ** 2521 ** ^This function causes any pending database operation to abort and 2522 ** return at its earliest opportunity. This routine is typically 2523 ** called in response to a user action such as pressing "Cancel" 2524 ** or Ctrl-C where the user wants a long query operation to halt 2525 ** immediately. 2526 ** 2527 ** ^It is safe to call this routine from a thread different from the 2528 ** thread that is currently running the database operation. But it 2529 ** is not safe to call this routine with a [database connection] that 2530 ** is closed or might close before sqlite3_interrupt() returns. 2531 ** 2532 ** ^If an SQL operation is very nearly finished at the time when 2533 ** sqlite3_interrupt() is called, then it might not have an opportunity 2534 ** to be interrupted and might continue to completion. 2535 ** 2536 ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. 2537 ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE 2538 ** that is inside an explicit transaction, then the entire transaction 2539 ** will be rolled back automatically. 2540 ** 2541 ** ^The sqlite3_interrupt(D) call is in effect until all currently running 2542 ** SQL statements on [database connection] D complete. ^Any new SQL statements 2543 ** that are started after the sqlite3_interrupt() call and before the 2544 ** running statement count reaches zero are interrupted as if they had been 2545 ** running prior to the sqlite3_interrupt() call. ^New SQL statements 2546 ** that are started after the running statement count reaches zero are 2547 ** not effected by the sqlite3_interrupt(). 2548 ** ^A call to sqlite3_interrupt(D) that occurs when there are no running 2549 ** SQL statements is a no-op and has no effect on SQL statements 2550 ** that are started after the sqlite3_interrupt() call returns. 2551 */ 2552 SQLITE_API void sqlite3_interrupt(sqlite3*); 2553 2554 /* 2555 ** CAPI3REF: Determine If An SQL Statement Is Complete 2556 ** 2557 ** These routines are useful during command-line input to determine if the 2558 ** currently entered text seems to form a complete SQL statement or 2559 ** if additional input is needed before sending the text into 2560 ** SQLite for parsing. ^These routines return 1 if the input string 2561 ** appears to be a complete SQL statement. ^A statement is judged to be 2562 ** complete if it ends with a semicolon token and is not a prefix of a 2563 ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within 2564 ** string literals or quoted identifier names or comments are not 2565 ** independent tokens (they are part of the token in which they are 2566 ** embedded) and thus do not count as a statement terminator. ^Whitespace 2567 ** and comments that follow the final semicolon are ignored. 2568 ** 2569 ** ^These routines return 0 if the statement is incomplete. ^If a 2570 ** memory allocation fails, then SQLITE_NOMEM is returned. 2571 ** 2572 ** ^These routines do not parse the SQL statements thus 2573 ** will not detect syntactically incorrect SQL. 2574 ** 2575 ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior 2576 ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked 2577 ** automatically by sqlite3_complete16(). If that initialization fails, 2578 ** then the return value from sqlite3_complete16() will be non-zero 2579 ** regardless of whether or not the input SQL is complete.)^ 2580 ** 2581 ** The input to [sqlite3_complete()] must be a zero-terminated 2582 ** UTF-8 string. 2583 ** 2584 ** The input to [sqlite3_complete16()] must be a zero-terminated 2585 ** UTF-16 string in native byte order. 2586 */ 2587 SQLITE_API int sqlite3_complete(const char *sql); 2588 SQLITE_API int sqlite3_complete16(const void *sql); 2589 2590 /* 2591 ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors 2592 ** KEYWORDS: {busy-handler callback} {busy handler} 2593 ** METHOD: sqlite3 2594 ** 2595 ** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X 2596 ** that might be invoked with argument P whenever 2597 ** an attempt is made to access a database table associated with 2598 ** [database connection] D when another thread 2599 ** or process has the table locked. 2600 ** The sqlite3_busy_handler() interface is used to implement 2601 ** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout]. 2602 ** 2603 ** ^If the busy callback is NULL, then [SQLITE_BUSY] 2604 ** is returned immediately upon encountering the lock. ^If the busy callback 2605 ** is not NULL, then the callback might be invoked with two arguments. 2606 ** 2607 ** ^The first argument to the busy handler is a copy of the void* pointer which 2608 ** is the third argument to sqlite3_busy_handler(). ^The second argument to 2609 ** the busy handler callback is the number of times that the busy handler has 2610 ** been invoked previously for the same locking event. ^If the 2611 ** busy callback returns 0, then no additional attempts are made to 2612 ** access the database and [SQLITE_BUSY] is returned 2613 ** to the application. 2614 ** ^If the callback returns non-zero, then another attempt 2615 ** is made to access the database and the cycle repeats. 2616 ** 2617 ** The presence of a busy handler does not guarantee that it will be invoked 2618 ** when there is lock contention. ^If SQLite determines that invoking the busy 2619 ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] 2620 ** to the application instead of invoking the 2621 ** busy handler. 2622 ** Consider a scenario where one process is holding a read lock that 2623 ** it is trying to promote to a reserved lock and 2624 ** a second process is holding a reserved lock that it is trying 2625 ** to promote to an exclusive lock. The first process cannot proceed 2626 ** because it is blocked by the second and the second process cannot 2627 ** proceed because it is blocked by the first. If both processes 2628 ** invoke the busy handlers, neither will make any progress. Therefore, 2629 ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this 2630 ** will induce the first process to release its read lock and allow 2631 ** the second process to proceed. 2632 ** 2633 ** ^The default busy callback is NULL. 2634 ** 2635 ** ^(There can only be a single busy handler defined for each 2636 ** [database connection]. Setting a new busy handler clears any 2637 ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] 2638 ** or evaluating [PRAGMA busy_timeout=N] will change the 2639 ** busy handler and thus clear any previously set busy handler. 2640 ** 2641 ** The busy callback should not take any actions which modify the 2642 ** database connection that invoked the busy handler. In other words, 2643 ** the busy handler is not reentrant. Any such actions 2644 ** result in undefined behavior. 2645 ** 2646 ** A busy handler must not close the database connection 2647 ** or [prepared statement] that invoked the busy handler. 2648 */ 2649 SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*); 2650 2651 /* 2652 ** CAPI3REF: Set A Busy Timeout 2653 ** METHOD: sqlite3 2654 ** 2655 ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps 2656 ** for a specified amount of time when a table is locked. ^The handler 2657 ** will sleep multiple times until at least "ms" milliseconds of sleeping 2658 ** have accumulated. ^After at least "ms" milliseconds of sleeping, 2659 ** the handler returns 0 which causes [sqlite3_step()] to return 2660 ** [SQLITE_BUSY]. 2661 ** 2662 ** ^Calling this routine with an argument less than or equal to zero 2663 ** turns off all busy handlers. 2664 ** 2665 ** ^(There can only be a single busy handler for a particular 2666 ** [database connection] at any given moment. If another busy handler 2667 ** was defined (using [sqlite3_busy_handler()]) prior to calling 2668 ** this routine, that other busy handler is cleared.)^ 2669 ** 2670 ** See also: [PRAGMA busy_timeout] 2671 */ 2672 SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); 2673 2674 /* 2675 ** CAPI3REF: Convenience Routines For Running Queries 2676 ** METHOD: sqlite3 2677 ** 2678 ** This is a legacy interface that is preserved for backwards compatibility. 2679 ** Use of this interface is not recommended. 2680 ** 2681 ** Definition: A <b>result table</b> is memory data structure created by the 2682 ** [sqlite3_get_table()] interface. A result table records the 2683 ** complete query results from one or more queries. 2684 ** 2685 ** The table conceptually has a number of rows and columns. But 2686 ** these numbers are not part of the result table itself. These 2687 ** numbers are obtained separately. Let N be the number of rows 2688 ** and M be the number of columns. 2689 ** 2690 ** A result table is an array of pointers to zero-terminated UTF-8 strings. 2691 ** There are (N+1)*M elements in the array. The first M pointers point 2692 ** to zero-terminated strings that contain the names of the columns. 2693 ** The remaining entries all point to query results. NULL values result 2694 ** in NULL pointers. All other values are in their UTF-8 zero-terminated 2695 ** string representation as returned by [sqlite3_column_text()]. 2696 ** 2697 ** A result table might consist of one or more memory allocations. 2698 ** It is not safe to pass a result table directly to [sqlite3_free()]. 2699 ** A result table should be deallocated using [sqlite3_free_table()]. 2700 ** 2701 ** ^(As an example of the result table format, suppose a query result 2702 ** is as follows: 2703 ** 2704 ** <blockquote><pre> 2705 ** Name | Age 2706 ** ----------------------- 2707 ** Alice | 43 2708 ** Bob | 28 2709 ** Cindy | 21 2710 ** </pre></blockquote> 2711 ** 2712 ** There are two columns (M==2) and three rows (N==3). Thus the 2713 ** result table has 8 entries. Suppose the result table is stored 2714 ** in an array named azResult. Then azResult holds this content: 2715 ** 2716 ** <blockquote><pre> 2717 ** azResult[0] = "Name"; 2718 ** azResult[1] = "Age"; 2719 ** azResult[2] = "Alice"; 2720 ** azResult[3] = "43"; 2721 ** azResult[4] = "Bob"; 2722 ** azResult[5] = "28"; 2723 ** azResult[6] = "Cindy"; 2724 ** azResult[7] = "21"; 2725 ** </pre></blockquote>)^ 2726 ** 2727 ** ^The sqlite3_get_table() function evaluates one or more 2728 ** semicolon-separated SQL statements in the zero-terminated UTF-8 2729 ** string of its 2nd parameter and returns a result table to the 2730 ** pointer given in its 3rd parameter. 2731 ** 2732 ** After the application has finished with the result from sqlite3_get_table(), 2733 ** it must pass the result table pointer to sqlite3_free_table() in order to 2734 ** release the memory that was malloced. Because of the way the 2735 ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling 2736 ** function must not try to call [sqlite3_free()] directly. Only 2737 ** [sqlite3_free_table()] is able to release the memory properly and safely. 2738 ** 2739 ** The sqlite3_get_table() interface is implemented as a wrapper around 2740 ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access 2741 ** to any internal data structures of SQLite. It uses only the public 2742 ** interface defined here. As a consequence, errors that occur in the 2743 ** wrapper layer outside of the internal [sqlite3_exec()] call are not 2744 ** reflected in subsequent calls to [sqlite3_errcode()] or 2745 ** [sqlite3_errmsg()]. 2746 */ 2747 SQLITE_API int sqlite3_get_table( 2748 sqlite3 *db, /* An open database */ 2749 const char *zSql, /* SQL to be evaluated */ 2750 char ***pazResult, /* Results of the query */ 2751 int *pnRow, /* Number of result rows written here */ 2752 int *pnColumn, /* Number of result columns written here */ 2753 char **pzErrmsg /* Error msg written here */ 2754 ); 2755 SQLITE_API void sqlite3_free_table(char **result); 2756 2757 /* 2758 ** CAPI3REF: Formatted String Printing Functions 2759 ** 2760 ** These routines are work-alikes of the "printf()" family of functions 2761 ** from the standard C library. 2762 ** These routines understand most of the common formatting options from 2763 ** the standard library printf() 2764 ** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]). 2765 ** See the [built-in printf()] documentation for details. 2766 ** 2767 ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their 2768 ** results into memory obtained from [sqlite3_malloc64()]. 2769 ** The strings returned by these two routines should be 2770 ** released by [sqlite3_free()]. ^Both routines return a 2771 ** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough 2772 ** memory to hold the resulting string. 2773 ** 2774 ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from 2775 ** the standard C library. The result is written into the 2776 ** buffer supplied as the second parameter whose size is given by 2777 ** the first parameter. Note that the order of the 2778 ** first two parameters is reversed from snprintf().)^ This is an 2779 ** historical accident that cannot be fixed without breaking 2780 ** backwards compatibility. ^(Note also that sqlite3_snprintf() 2781 ** returns a pointer to its buffer instead of the number of 2782 ** characters actually written into the buffer.)^ We admit that 2783 ** the number of characters written would be a more useful return 2784 ** value but we cannot change the implementation of sqlite3_snprintf() 2785 ** now without breaking compatibility. 2786 ** 2787 ** ^As long as the buffer size is greater than zero, sqlite3_snprintf() 2788 ** guarantees that the buffer is always zero-terminated. ^The first 2789 ** parameter "n" is the total size of the buffer, including space for 2790 ** the zero terminator. So the longest string that can be completely 2791 ** written will be n-1 characters. 2792 ** 2793 ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). 2794 ** 2795 ** See also: [built-in printf()], [printf() SQL function] 2796 */ 2797 SQLITE_API char *sqlite3_mprintf(const char*,...); 2798 SQLITE_API char *sqlite3_vmprintf(const char*, va_list); 2799 SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...); 2800 SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list); 2801 2802 /* 2803 ** CAPI3REF: Memory Allocation Subsystem 2804 ** 2805 ** The SQLite core uses these three routines for all of its own 2806 ** internal memory allocation needs. "Core" in the previous sentence 2807 ** does not include operating-system specific [VFS] implementation. The 2808 ** Windows VFS uses native malloc() and free() for some operations. 2809 ** 2810 ** ^The sqlite3_malloc() routine returns a pointer to a block 2811 ** of memory at least N bytes in length, where N is the parameter. 2812 ** ^If sqlite3_malloc() is unable to obtain sufficient free 2813 ** memory, it returns a NULL pointer. ^If the parameter N to 2814 ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns 2815 ** a NULL pointer. 2816 ** 2817 ** ^The sqlite3_malloc64(N) routine works just like 2818 ** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead 2819 ** of a signed 32-bit integer. 2820 ** 2821 ** ^Calling sqlite3_free() with a pointer previously returned 2822 ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so 2823 ** that it might be reused. ^The sqlite3_free() routine is 2824 ** a no-op if is called with a NULL pointer. Passing a NULL pointer 2825 ** to sqlite3_free() is harmless. After being freed, memory 2826 ** should neither be read nor written. Even reading previously freed 2827 ** memory might result in a segmentation fault or other severe error. 2828 ** Memory corruption, a segmentation fault, or other severe error 2829 ** might result if sqlite3_free() is called with a non-NULL pointer that 2830 ** was not obtained from sqlite3_malloc() or sqlite3_realloc(). 2831 ** 2832 ** ^The sqlite3_realloc(X,N) interface attempts to resize a 2833 ** prior memory allocation X to be at least N bytes. 2834 ** ^If the X parameter to sqlite3_realloc(X,N) 2835 ** is a NULL pointer then its behavior is identical to calling 2836 ** sqlite3_malloc(N). 2837 ** ^If the N parameter to sqlite3_realloc(X,N) is zero or 2838 ** negative then the behavior is exactly the same as calling 2839 ** sqlite3_free(X). 2840 ** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation 2841 ** of at least N bytes in size or NULL if insufficient memory is available. 2842 ** ^If M is the size of the prior allocation, then min(N,M) bytes 2843 ** of the prior allocation are copied into the beginning of buffer returned 2844 ** by sqlite3_realloc(X,N) and the prior allocation is freed. 2845 ** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the 2846 ** prior allocation is not freed. 2847 ** 2848 ** ^The sqlite3_realloc64(X,N) interfaces works the same as 2849 ** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead 2850 ** of a 32-bit signed integer. 2851 ** 2852 ** ^If X is a memory allocation previously obtained from sqlite3_malloc(), 2853 ** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then 2854 ** sqlite3_msize(X) returns the size of that memory allocation in bytes. 2855 ** ^The value returned by sqlite3_msize(X) might be larger than the number 2856 ** of bytes requested when X was allocated. ^If X is a NULL pointer then 2857 ** sqlite3_msize(X) returns zero. If X points to something that is not 2858 ** the beginning of memory allocation, or if it points to a formerly 2859 ** valid memory allocation that has now been freed, then the behavior 2860 ** of sqlite3_msize(X) is undefined and possibly harmful. 2861 ** 2862 ** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(), 2863 ** sqlite3_malloc64(), and sqlite3_realloc64() 2864 ** is always aligned to at least an 8 byte boundary, or to a 2865 ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time 2866 ** option is used. 2867 ** 2868 ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] 2869 ** must be either NULL or else pointers obtained from a prior 2870 ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have 2871 ** not yet been released. 2872 ** 2873 ** The application must not read or write any part of 2874 ** a block of memory after it has been released using 2875 ** [sqlite3_free()] or [sqlite3_realloc()]. 2876 */ 2877 SQLITE_API void *sqlite3_malloc(int); 2878 SQLITE_API void *sqlite3_malloc64(sqlite3_uint64); 2879 SQLITE_API void *sqlite3_realloc(void*, int); 2880 SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64); 2881 SQLITE_API void sqlite3_free(void*); 2882 SQLITE_API sqlite3_uint64 sqlite3_msize(void*); 2883 2884 /* 2885 ** CAPI3REF: Memory Allocator Statistics 2886 ** 2887 ** SQLite provides these two interfaces for reporting on the status 2888 ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] 2889 ** routines, which form the built-in memory allocation subsystem. 2890 ** 2891 ** ^The [sqlite3_memory_used()] routine returns the number of bytes 2892 ** of memory currently outstanding (malloced but not freed). 2893 ** ^The [sqlite3_memory_highwater()] routine returns the maximum 2894 ** value of [sqlite3_memory_used()] since the high-water mark 2895 ** was last reset. ^The values returned by [sqlite3_memory_used()] and 2896 ** [sqlite3_memory_highwater()] include any overhead 2897 ** added by SQLite in its implementation of [sqlite3_malloc()], 2898 ** but not overhead added by the any underlying system library 2899 ** routines that [sqlite3_malloc()] may call. 2900 ** 2901 ** ^The memory high-water mark is reset to the current value of 2902 ** [sqlite3_memory_used()] if and only if the parameter to 2903 ** [sqlite3_memory_highwater()] is true. ^The value returned 2904 ** by [sqlite3_memory_highwater(1)] is the high-water mark 2905 ** prior to the reset. 2906 */ 2907 SQLITE_API sqlite3_int64 sqlite3_memory_used(void); 2908 SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag); 2909 2910 /* 2911 ** CAPI3REF: Pseudo-Random Number Generator 2912 ** 2913 ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to 2914 ** select random [ROWID | ROWIDs] when inserting new records into a table that 2915 ** already uses the largest possible [ROWID]. The PRNG is also used for 2916 ** the built-in random() and randomblob() SQL functions. This interface allows 2917 ** applications to access the same PRNG for other purposes. 2918 ** 2919 ** ^A call to this routine stores N bytes of randomness into buffer P. 2920 ** ^The P parameter can be a NULL pointer. 2921 ** 2922 ** ^If this routine has not been previously called or if the previous 2923 ** call had N less than one or a NULL pointer for P, then the PRNG is 2924 ** seeded using randomness obtained from the xRandomness method of 2925 ** the default [sqlite3_vfs] object. 2926 ** ^If the previous call to this routine had an N of 1 or more and a 2927 ** non-NULL P then the pseudo-randomness is generated 2928 ** internally and without recourse to the [sqlite3_vfs] xRandomness 2929 ** method. 2930 */ 2931 SQLITE_API void sqlite3_randomness(int N, void *P); 2932 2933 /* 2934 ** CAPI3REF: Compile-Time Authorization Callbacks 2935 ** METHOD: sqlite3 2936 ** KEYWORDS: {authorizer callback} 2937 ** 2938 ** ^This routine registers an authorizer callback with a particular 2939 ** [database connection], supplied in the first argument. 2940 ** ^The authorizer callback is invoked as SQL statements are being compiled 2941 ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], 2942 ** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()], 2943 ** and [sqlite3_prepare16_v3()]. ^At various 2944 ** points during the compilation process, as logic is being created 2945 ** to perform various actions, the authorizer callback is invoked to 2946 ** see if those actions are allowed. ^The authorizer callback should 2947 ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the 2948 ** specific action but allow the SQL statement to continue to be 2949 ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be 2950 ** rejected with an error. ^If the authorizer callback returns 2951 ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] 2952 ** then the [sqlite3_prepare_v2()] or equivalent call that triggered 2953 ** the authorizer will fail with an error message. 2954 ** 2955 ** When the callback returns [SQLITE_OK], that means the operation 2956 ** requested is ok. ^When the callback returns [SQLITE_DENY], the 2957 ** [sqlite3_prepare_v2()] or equivalent call that triggered the 2958 ** authorizer will fail with an error message explaining that 2959 ** access is denied. 2960 ** 2961 ** ^The first parameter to the authorizer callback is a copy of the third 2962 ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter 2963 ** to the callback is an integer [SQLITE_COPY | action code] that specifies 2964 ** the particular action to be authorized. ^The third through sixth parameters 2965 ** to the callback are either NULL pointers or zero-terminated strings 2966 ** that contain additional details about the action to be authorized. 2967 ** Applications must always be prepared to encounter a NULL pointer in any 2968 ** of the third through the sixth parameters of the authorization callback. 2969 ** 2970 ** ^If the action code is [SQLITE_READ] 2971 ** and the callback returns [SQLITE_IGNORE] then the 2972 ** [prepared statement] statement is constructed to substitute 2973 ** a NULL value in place of the table column that would have 2974 ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] 2975 ** return can be used to deny an untrusted user access to individual 2976 ** columns of a table. 2977 ** ^When a table is referenced by a [SELECT] but no column values are 2978 ** extracted from that table (for example in a query like 2979 ** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback 2980 ** is invoked once for that table with a column name that is an empty string. 2981 ** ^If the action code is [SQLITE_DELETE] and the callback returns 2982 ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the 2983 ** [truncate optimization] is disabled and all rows are deleted individually. 2984 ** 2985 ** An authorizer is used when [sqlite3_prepare | preparing] 2986 ** SQL statements from an untrusted source, to ensure that the SQL statements 2987 ** do not try to access data they are not allowed to see, or that they do not 2988 ** try to execute malicious statements that damage the database. For 2989 ** example, an application may allow a user to enter arbitrary 2990 ** SQL queries for evaluation by a database. But the application does 2991 ** not want the user to be able to make arbitrary changes to the 2992 ** database. An authorizer could then be put in place while the 2993 ** user-entered SQL is being [sqlite3_prepare | prepared] that 2994 ** disallows everything except [SELECT] statements. 2995 ** 2996 ** Applications that need to process SQL from untrusted sources 2997 ** might also consider lowering resource limits using [sqlite3_limit()] 2998 ** and limiting database size using the [max_page_count] [PRAGMA] 2999 ** in addition to using an authorizer. 3000 ** 3001 ** ^(Only a single authorizer can be in place on a database connection 3002 ** at a time. Each call to sqlite3_set_authorizer overrides the 3003 ** previous call.)^ ^Disable the authorizer by installing a NULL callback. 3004 ** The authorizer is disabled by default. 3005 ** 3006 ** The authorizer callback must not do anything that will modify 3007 ** the database connection that invoked the authorizer callback. 3008 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3009 ** database connections for the meaning of "modify" in this paragraph. 3010 ** 3011 ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the 3012 ** statement might be re-prepared during [sqlite3_step()] due to a 3013 ** schema change. Hence, the application should ensure that the 3014 ** correct authorizer callback remains in place during the [sqlite3_step()]. 3015 ** 3016 ** ^Note that the authorizer callback is invoked only during 3017 ** [sqlite3_prepare()] or its variants. Authorization is not 3018 ** performed during statement evaluation in [sqlite3_step()], unless 3019 ** as stated in the previous paragraph, sqlite3_step() invokes 3020 ** sqlite3_prepare_v2() to reprepare a statement after a schema change. 3021 */ 3022 SQLITE_API int sqlite3_set_authorizer( 3023 sqlite3*, 3024 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), 3025 void *pUserData 3026 ); 3027 3028 /* 3029 ** CAPI3REF: Authorizer Return Codes 3030 ** 3031 ** The [sqlite3_set_authorizer | authorizer callback function] must 3032 ** return either [SQLITE_OK] or one of these two constants in order 3033 ** to signal SQLite whether or not the action is permitted. See the 3034 ** [sqlite3_set_authorizer | authorizer documentation] for additional 3035 ** information. 3036 ** 3037 ** Note that SQLITE_IGNORE is also used as a [conflict resolution mode] 3038 ** returned from the [sqlite3_vtab_on_conflict()] interface. 3039 */ 3040 #define SQLITE_DENY 1 /* Abort the SQL statement with an error */ 3041 #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ 3042 3043 /* 3044 ** CAPI3REF: Authorizer Action Codes 3045 ** 3046 ** The [sqlite3_set_authorizer()] interface registers a callback function 3047 ** that is invoked to authorize certain SQL statement actions. The 3048 ** second parameter to the callback is an integer code that specifies 3049 ** what action is being authorized. These are the integer action codes that 3050 ** the authorizer callback may be passed. 3051 ** 3052 ** These action code values signify what kind of operation is to be 3053 ** authorized. The 3rd and 4th parameters to the authorization 3054 ** callback function will be parameters or NULL depending on which of these 3055 ** codes is used as the second parameter. ^(The 5th parameter to the 3056 ** authorizer callback is the name of the database ("main", "temp", 3057 ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback 3058 ** is the name of the inner-most trigger or view that is responsible for 3059 ** the access attempt or NULL if this access attempt is directly from 3060 ** top-level SQL code. 3061 */ 3062 /******************************************* 3rd ************ 4th ***********/ 3063 #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ 3064 #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ 3065 #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ 3066 #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ 3067 #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ 3068 #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ 3069 #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ 3070 #define SQLITE_CREATE_VIEW 8 /* View Name NULL */ 3071 #define SQLITE_DELETE 9 /* Table Name NULL */ 3072 #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ 3073 #define SQLITE_DROP_TABLE 11 /* Table Name NULL */ 3074 #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ 3075 #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ 3076 #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ 3077 #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ 3078 #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ 3079 #define SQLITE_DROP_VIEW 17 /* View Name NULL */ 3080 #define SQLITE_INSERT 18 /* Table Name NULL */ 3081 #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ 3082 #define SQLITE_READ 20 /* Table Name Column Name */ 3083 #define SQLITE_SELECT 21 /* NULL NULL */ 3084 #define SQLITE_TRANSACTION 22 /* Operation NULL */ 3085 #define SQLITE_UPDATE 23 /* Table Name Column Name */ 3086 #define SQLITE_ATTACH 24 /* Filename NULL */ 3087 #define SQLITE_DETACH 25 /* Database Name NULL */ 3088 #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ 3089 #define SQLITE_REINDEX 27 /* Index Name NULL */ 3090 #define SQLITE_ANALYZE 28 /* Table Name NULL */ 3091 #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ 3092 #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ 3093 #define SQLITE_FUNCTION 31 /* NULL Function Name */ 3094 #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ 3095 #define SQLITE_COPY 0 /* No longer used */ 3096 #define SQLITE_RECURSIVE 33 /* NULL NULL */ 3097 3098 /* 3099 ** CAPI3REF: Tracing And Profiling Functions 3100 ** METHOD: sqlite3 3101 ** 3102 ** These routines are deprecated. Use the [sqlite3_trace_v2()] interface 3103 ** instead of the routines described here. 3104 ** 3105 ** These routines register callback functions that can be used for 3106 ** tracing and profiling the execution of SQL statements. 3107 ** 3108 ** ^The callback function registered by sqlite3_trace() is invoked at 3109 ** various times when an SQL statement is being run by [sqlite3_step()]. 3110 ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the 3111 ** SQL statement text as the statement first begins executing. 3112 ** ^(Additional sqlite3_trace() callbacks might occur 3113 ** as each triggered subprogram is entered. The callbacks for triggers 3114 ** contain a UTF-8 SQL comment that identifies the trigger.)^ 3115 ** 3116 ** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit 3117 ** the length of [bound parameter] expansion in the output of sqlite3_trace(). 3118 ** 3119 ** ^The callback function registered by sqlite3_profile() is invoked 3120 ** as each SQL statement finishes. ^The profile callback contains 3121 ** the original statement text and an estimate of wall-clock time 3122 ** of how long that statement took to run. ^The profile callback 3123 ** time is in units of nanoseconds, however the current implementation 3124 ** is only capable of millisecond resolution so the six least significant 3125 ** digits in the time are meaningless. Future versions of SQLite 3126 ** might provide greater resolution on the profiler callback. Invoking 3127 ** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the 3128 ** profile callback. 3129 */ 3130 SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*, 3131 void(*xTrace)(void*,const char*), void*); 3132 SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*, 3133 void(*xProfile)(void*,const char*,sqlite3_uint64), void*); 3134 3135 /* 3136 ** CAPI3REF: SQL Trace Event Codes 3137 ** KEYWORDS: SQLITE_TRACE 3138 ** 3139 ** These constants identify classes of events that can be monitored 3140 ** using the [sqlite3_trace_v2()] tracing logic. The M argument 3141 ** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of 3142 ** the following constants. ^The first argument to the trace callback 3143 ** is one of the following constants. 3144 ** 3145 ** New tracing constants may be added in future releases. 3146 ** 3147 ** ^A trace callback has four arguments: xCallback(T,C,P,X). 3148 ** ^The T argument is one of the integer type codes above. 3149 ** ^The C argument is a copy of the context pointer passed in as the 3150 ** fourth argument to [sqlite3_trace_v2()]. 3151 ** The P and X arguments are pointers whose meanings depend on T. 3152 ** 3153 ** <dl> 3154 ** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt> 3155 ** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement 3156 ** first begins running and possibly at other times during the 3157 ** execution of the prepared statement, such as at the start of each 3158 ** trigger subprogram. ^The P argument is a pointer to the 3159 ** [prepared statement]. ^The X argument is a pointer to a string which 3160 ** is the unexpanded SQL text of the prepared statement or an SQL comment 3161 ** that indicates the invocation of a trigger. ^The callback can compute 3162 ** the same text that would have been returned by the legacy [sqlite3_trace()] 3163 ** interface by using the X argument when X begins with "--" and invoking 3164 ** [sqlite3_expanded_sql(P)] otherwise. 3165 ** 3166 ** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt> 3167 ** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same 3168 ** information as is provided by the [sqlite3_profile()] callback. 3169 ** ^The P argument is a pointer to the [prepared statement] and the 3170 ** X argument points to a 64-bit integer which is the estimated of 3171 ** the number of nanosecond that the prepared statement took to run. 3172 ** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes. 3173 ** 3174 ** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt> 3175 ** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared 3176 ** statement generates a single row of result. 3177 ** ^The P argument is a pointer to the [prepared statement] and the 3178 ** X argument is unused. 3179 ** 3180 ** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt> 3181 ** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database 3182 ** connection closes. 3183 ** ^The P argument is a pointer to the [database connection] object 3184 ** and the X argument is unused. 3185 ** </dl> 3186 */ 3187 #define SQLITE_TRACE_STMT 0x01 3188 #define SQLITE_TRACE_PROFILE 0x02 3189 #define SQLITE_TRACE_ROW 0x04 3190 #define SQLITE_TRACE_CLOSE 0x08 3191 3192 /* 3193 ** CAPI3REF: SQL Trace Hook 3194 ** METHOD: sqlite3 3195 ** 3196 ** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback 3197 ** function X against [database connection] D, using property mask M 3198 ** and context pointer P. ^If the X callback is 3199 ** NULL or if the M mask is zero, then tracing is disabled. The 3200 ** M argument should be the bitwise OR-ed combination of 3201 ** zero or more [SQLITE_TRACE] constants. 3202 ** 3203 ** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides 3204 ** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2(). 3205 ** 3206 ** ^The X callback is invoked whenever any of the events identified by 3207 ** mask M occur. ^The integer return value from the callback is currently 3208 ** ignored, though this may change in future releases. Callback 3209 ** implementations should return zero to ensure future compatibility. 3210 ** 3211 ** ^A trace callback is invoked with four arguments: callback(T,C,P,X). 3212 ** ^The T argument is one of the [SQLITE_TRACE] 3213 ** constants to indicate why the callback was invoked. 3214 ** ^The C argument is a copy of the context pointer. 3215 ** The P and X arguments are pointers whose meanings depend on T. 3216 ** 3217 ** The sqlite3_trace_v2() interface is intended to replace the legacy 3218 ** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which 3219 ** are deprecated. 3220 */ 3221 SQLITE_API int sqlite3_trace_v2( 3222 sqlite3*, 3223 unsigned uMask, 3224 int(*xCallback)(unsigned,void*,void*,void*), 3225 void *pCtx 3226 ); 3227 3228 /* 3229 ** CAPI3REF: Query Progress Callbacks 3230 ** METHOD: sqlite3 3231 ** 3232 ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback 3233 ** function X to be invoked periodically during long running calls to 3234 ** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for 3235 ** database connection D. An example use for this 3236 ** interface is to keep a GUI updated during a large query. 3237 ** 3238 ** ^The parameter P is passed through as the only parameter to the 3239 ** callback function X. ^The parameter N is the approximate number of 3240 ** [virtual machine instructions] that are evaluated between successive 3241 ** invocations of the callback X. ^If N is less than one then the progress 3242 ** handler is disabled. 3243 ** 3244 ** ^Only a single progress handler may be defined at one time per 3245 ** [database connection]; setting a new progress handler cancels the 3246 ** old one. ^Setting parameter X to NULL disables the progress handler. 3247 ** ^The progress handler is also disabled by setting N to a value less 3248 ** than 1. 3249 ** 3250 ** ^If the progress callback returns non-zero, the operation is 3251 ** interrupted. This feature can be used to implement a 3252 ** "Cancel" button on a GUI progress dialog box. 3253 ** 3254 ** The progress handler callback must not do anything that will modify 3255 ** the database connection that invoked the progress handler. 3256 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3257 ** database connections for the meaning of "modify" in this paragraph. 3258 ** 3259 */ 3260 SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); 3261 3262 /* 3263 ** CAPI3REF: Opening A New Database Connection 3264 ** CONSTRUCTOR: sqlite3 3265 ** 3266 ** ^These routines open an SQLite database file as specified by the 3267 ** filename argument. ^The filename argument is interpreted as UTF-8 for 3268 ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte 3269 ** order for sqlite3_open16(). ^(A [database connection] handle is usually 3270 ** returned in *ppDb, even if an error occurs. The only exception is that 3271 ** if SQLite is unable to allocate memory to hold the [sqlite3] object, 3272 ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] 3273 ** object.)^ ^(If the database is opened (and/or created) successfully, then 3274 ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The 3275 ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain 3276 ** an English language description of the error following a failure of any 3277 ** of the sqlite3_open() routines. 3278 ** 3279 ** ^The default encoding will be UTF-8 for databases created using 3280 ** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases 3281 ** created using sqlite3_open16() will be UTF-16 in the native byte order. 3282 ** 3283 ** Whether or not an error occurs when it is opened, resources 3284 ** associated with the [database connection] handle should be released by 3285 ** passing it to [sqlite3_close()] when it is no longer required. 3286 ** 3287 ** The sqlite3_open_v2() interface works like sqlite3_open() 3288 ** except that it accepts two additional parameters for additional control 3289 ** over the new database connection. ^(The flags parameter to 3290 ** sqlite3_open_v2() must include, at a minimum, one of the following 3291 ** three flag combinations:)^ 3292 ** 3293 ** <dl> 3294 ** ^(<dt>[SQLITE_OPEN_READONLY]</dt> 3295 ** <dd>The database is opened in read-only mode. If the database does not 3296 ** already exist, an error is returned.</dd>)^ 3297 ** 3298 ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt> 3299 ** <dd>The database is opened for reading and writing if possible, or reading 3300 ** only if the file is write protected by the operating system. In either 3301 ** case the database must already exist, otherwise an error is returned.</dd>)^ 3302 ** 3303 ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> 3304 ** <dd>The database is opened for reading and writing, and is created if 3305 ** it does not already exist. This is the behavior that is always used for 3306 ** sqlite3_open() and sqlite3_open16().</dd>)^ 3307 ** </dl> 3308 ** 3309 ** In addition to the required flags, the following optional flags are 3310 ** also supported: 3311 ** 3312 ** <dl> 3313 ** ^(<dt>[SQLITE_OPEN_URI]</dt> 3314 ** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^ 3315 ** 3316 ** ^(<dt>[SQLITE_OPEN_MEMORY]</dt> 3317 ** <dd>The database will be opened as an in-memory database. The database 3318 ** is named by the "filename" argument for the purposes of cache-sharing, 3319 ** if shared cache mode is enabled, but the "filename" is otherwise ignored. 3320 ** </dd>)^ 3321 ** 3322 ** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt> 3323 ** <dd>The new database connection will use the "multi-thread" 3324 ** [threading mode].)^ This means that separate threads are allowed 3325 ** to use SQLite at the same time, as long as each thread is using 3326 ** a different [database connection]. 3327 ** 3328 ** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt> 3329 ** <dd>The new database connection will use the "serialized" 3330 ** [threading mode].)^ This means the multiple threads can safely 3331 ** attempt to use the same database connection at the same time. 3332 ** (Mutexes will block any actual concurrency, but in this mode 3333 ** there is no harm in trying.) 3334 ** 3335 ** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt> 3336 ** <dd>The database is opened [shared cache] enabled, overriding 3337 ** the default shared cache setting provided by 3338 ** [sqlite3_enable_shared_cache()].)^ 3339 ** 3340 ** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt> 3341 ** <dd>The database is opened [shared cache] disabled, overriding 3342 ** the default shared cache setting provided by 3343 ** [sqlite3_enable_shared_cache()].)^ 3344 ** 3345 ** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt> 3346 ** <dd>The database filename is not allowed to be a symbolic link</dd> 3347 ** </dl>)^ 3348 ** 3349 ** If the 3rd parameter to sqlite3_open_v2() is not one of the 3350 ** required combinations shown above optionally combined with other 3351 ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] 3352 ** then the behavior is undefined. 3353 ** 3354 ** ^The fourth parameter to sqlite3_open_v2() is the name of the 3355 ** [sqlite3_vfs] object that defines the operating system interface that 3356 ** the new database connection should use. ^If the fourth parameter is 3357 ** a NULL pointer then the default [sqlite3_vfs] object is used. 3358 ** 3359 ** ^If the filename is ":memory:", then a private, temporary in-memory database 3360 ** is created for the connection. ^This in-memory database will vanish when 3361 ** the database connection is closed. Future versions of SQLite might 3362 ** make use of additional special filenames that begin with the ":" character. 3363 ** It is recommended that when a database filename actually does begin with 3364 ** a ":" character you should prefix the filename with a pathname such as 3365 ** "./" to avoid ambiguity. 3366 ** 3367 ** ^If the filename is an empty string, then a private, temporary 3368 ** on-disk database will be created. ^This private database will be 3369 ** automatically deleted as soon as the database connection is closed. 3370 ** 3371 ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3> 3372 ** 3373 ** ^If [URI filename] interpretation is enabled, and the filename argument 3374 ** begins with "file:", then the filename is interpreted as a URI. ^URI 3375 ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is 3376 ** set in the third argument to sqlite3_open_v2(), or if it has 3377 ** been enabled globally using the [SQLITE_CONFIG_URI] option with the 3378 ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. 3379 ** URI filename interpretation is turned off 3380 ** by default, but future releases of SQLite might enable URI filename 3381 ** interpretation by default. See "[URI filenames]" for additional 3382 ** information. 3383 ** 3384 ** URI filenames are parsed according to RFC 3986. ^If the URI contains an 3385 ** authority, then it must be either an empty string or the string 3386 ** "localhost". ^If the authority is not an empty string or "localhost", an 3387 ** error is returned to the caller. ^The fragment component of a URI, if 3388 ** present, is ignored. 3389 ** 3390 ** ^SQLite uses the path component of the URI as the name of the disk file 3391 ** which contains the database. ^If the path begins with a '/' character, 3392 ** then it is interpreted as an absolute path. ^If the path does not begin 3393 ** with a '/' (meaning that the authority section is omitted from the URI) 3394 ** then the path is interpreted as a relative path. 3395 ** ^(On windows, the first component of an absolute path 3396 ** is a drive specification (e.g. "C:").)^ 3397 ** 3398 ** [[core URI query parameters]] 3399 ** The query component of a URI may contain parameters that are interpreted 3400 ** either by SQLite itself, or by a [VFS | custom VFS implementation]. 3401 ** SQLite and its built-in [VFSes] interpret the 3402 ** following query parameters: 3403 ** 3404 ** <ul> 3405 ** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of 3406 ** a VFS object that provides the operating system interface that should 3407 ** be used to access the database file on disk. ^If this option is set to 3408 ** an empty string the default VFS object is used. ^Specifying an unknown 3409 ** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is 3410 ** present, then the VFS specified by the option takes precedence over 3411 ** the value passed as the fourth parameter to sqlite3_open_v2(). 3412 ** 3413 ** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw", 3414 ** "rwc", or "memory". Attempting to set it to any other value is 3415 ** an error)^. 3416 ** ^If "ro" is specified, then the database is opened for read-only 3417 ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the 3418 ** third argument to sqlite3_open_v2(). ^If the mode option is set to 3419 ** "rw", then the database is opened for read-write (but not create) 3420 ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had 3421 ** been set. ^Value "rwc" is equivalent to setting both 3422 ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is 3423 ** set to "memory" then a pure [in-memory database] that never reads 3424 ** or writes from disk is used. ^It is an error to specify a value for 3425 ** the mode parameter that is less restrictive than that specified by 3426 ** the flags passed in the third parameter to sqlite3_open_v2(). 3427 ** 3428 ** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or 3429 ** "private". ^Setting it to "shared" is equivalent to setting the 3430 ** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to 3431 ** sqlite3_open_v2(). ^Setting the cache parameter to "private" is 3432 ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit. 3433 ** ^If sqlite3_open_v2() is used and the "cache" parameter is present in 3434 ** a URI filename, its value overrides any behavior requested by setting 3435 ** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag. 3436 ** 3437 ** <li> <b>psow</b>: ^The psow parameter indicates whether or not the 3438 ** [powersafe overwrite] property does or does not apply to the 3439 ** storage media on which the database file resides. 3440 ** 3441 ** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter 3442 ** which if set disables file locking in rollback journal modes. This 3443 ** is useful for accessing a database on a filesystem that does not 3444 ** support locking. Caution: Database corruption might result if two 3445 ** or more processes write to the same database and any one of those 3446 ** processes uses nolock=1. 3447 ** 3448 ** <li> <b>immutable</b>: ^The immutable parameter is a boolean query 3449 ** parameter that indicates that the database file is stored on 3450 ** read-only media. ^When immutable is set, SQLite assumes that the 3451 ** database file cannot be changed, even by a process with higher 3452 ** privilege, and so the database is opened read-only and all locking 3453 ** and change detection is disabled. Caution: Setting the immutable 3454 ** property on a database file that does in fact change can result 3455 ** in incorrect query results and/or [SQLITE_CORRUPT] errors. 3456 ** See also: [SQLITE_IOCAP_IMMUTABLE]. 3457 ** 3458 ** </ul> 3459 ** 3460 ** ^Specifying an unknown parameter in the query component of a URI is not an 3461 ** error. Future versions of SQLite might understand additional query 3462 ** parameters. See "[query parameters with special meaning to SQLite]" for 3463 ** additional information. 3464 ** 3465 ** [[URI filename examples]] <h3>URI filename examples</h3> 3466 ** 3467 ** <table border="1" align=center cellpadding=5> 3468 ** <tr><th> URI filenames <th> Results 3469 ** <tr><td> file:data.db <td> 3470 ** Open the file "data.db" in the current directory. 3471 ** <tr><td> file:/home/fred/data.db<br> 3472 ** file:///home/fred/data.db <br> 3473 ** file://localhost/home/fred/data.db <br> <td> 3474 ** Open the database file "/home/fred/data.db". 3475 ** <tr><td> file://darkstar/home/fred/data.db <td> 3476 ** An error. "darkstar" is not a recognized authority. 3477 ** <tr><td style="white-space:nowrap"> 3478 ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db 3479 ** <td> Windows only: Open the file "data.db" on fred's desktop on drive 3480 ** C:. Note that the %20 escaping in this example is not strictly 3481 ** necessary - space characters can be used literally 3482 ** in URI filenames. 3483 ** <tr><td> file:data.db?mode=ro&cache=private <td> 3484 ** Open file "data.db" in the current directory for read-only access. 3485 ** Regardless of whether or not shared-cache mode is enabled by 3486 ** default, use a private cache. 3487 ** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td> 3488 ** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" 3489 ** that uses dot-files in place of posix advisory locking. 3490 ** <tr><td> file:data.db?mode=readonly <td> 3491 ** An error. "readonly" is not a valid option for the "mode" parameter. 3492 ** </table> 3493 ** 3494 ** ^URI hexadecimal escape sequences (%HH) are supported within the path and 3495 ** query components of a URI. A hexadecimal escape sequence consists of a 3496 ** percent sign - "%" - followed by exactly two hexadecimal digits 3497 ** specifying an octet value. ^Before the path or query components of a 3498 ** URI filename are interpreted, they are encoded using UTF-8 and all 3499 ** hexadecimal escape sequences replaced by a single byte containing the 3500 ** corresponding octet. If this process generates an invalid UTF-8 encoding, 3501 ** the results are undefined. 3502 ** 3503 ** <b>Note to Windows users:</b> The encoding used for the filename argument 3504 ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever 3505 ** codepage is currently defined. Filenames containing international 3506 ** characters must be converted to UTF-8 prior to passing them into 3507 ** sqlite3_open() or sqlite3_open_v2(). 3508 ** 3509 ** <b>Note to Windows Runtime users:</b> The temporary directory must be set 3510 ** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various 3511 ** features that require the use of temporary files may fail. 3512 ** 3513 ** See also: [sqlite3_temp_directory] 3514 */ 3515 SQLITE_API int sqlite3_open( 3516 const char *filename, /* Database filename (UTF-8) */ 3517 sqlite3 **ppDb /* OUT: SQLite db handle */ 3518 ); 3519 SQLITE_API int sqlite3_open16( 3520 const void *filename, /* Database filename (UTF-16) */ 3521 sqlite3 **ppDb /* OUT: SQLite db handle */ 3522 ); 3523 SQLITE_API int sqlite3_open_v2( 3524 const char *filename, /* Database filename (UTF-8) */ 3525 sqlite3 **ppDb, /* OUT: SQLite db handle */ 3526 int flags, /* Flags */ 3527 const char *zVfs /* Name of VFS module to use */ 3528 ); 3529 3530 /* 3531 ** CAPI3REF: Obtain Values For URI Parameters 3532 ** 3533 ** These are utility routines, useful to [VFS|custom VFS implementations], 3534 ** that check if a database file was a URI that contained a specific query 3535 ** parameter, and if so obtains the value of that query parameter. 3536 ** 3537 ** If F is the database filename pointer passed into the xOpen() method of 3538 ** a VFS implementation or it is the return value of [sqlite3_db_filename()] 3539 ** and if P is the name of the query parameter, then 3540 ** sqlite3_uri_parameter(F,P) returns the value of the P 3541 ** parameter if it exists or a NULL pointer if P does not appear as a 3542 ** query parameter on F. If P is a query parameter of F and it 3543 ** has no explicit value, then sqlite3_uri_parameter(F,P) returns 3544 ** a pointer to an empty string. 3545 ** 3546 ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean 3547 ** parameter and returns true (1) or false (0) according to the value 3548 ** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the 3549 ** value of query parameter P is one of "yes", "true", or "on" in any 3550 ** case or if the value begins with a non-zero number. The 3551 ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of 3552 ** query parameter P is one of "no", "false", or "off" in any case or 3553 ** if the value begins with a numeric zero. If P is not a query 3554 ** parameter on F or if the value of P does not match any of the 3555 ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). 3556 ** 3557 ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a 3558 ** 64-bit signed integer and returns that integer, or D if P does not 3559 ** exist. If the value of P is something other than an integer, then 3560 ** zero is returned. 3561 ** 3562 ** The sqlite3_uri_key(F,N) returns a pointer to the name (not 3563 ** the value) of the N-th query parameter for filename F, or a NULL 3564 ** pointer if N is less than zero or greater than the number of query 3565 ** parameters minus 1. The N value is zero-based so N should be 0 to obtain 3566 ** the name of the first query parameter, 1 for the second parameter, and 3567 ** so forth. 3568 ** 3569 ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and 3570 ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and 3571 ** is not a database file pathname pointer that the SQLite core passed 3572 ** into the xOpen VFS method, then the behavior of this routine is undefined 3573 ** and probably undesirable. 3574 ** 3575 ** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F 3576 ** parameter can also be the name of a rollback journal file or WAL file 3577 ** in addition to the main database file. Prior to version 3.31.0, these 3578 ** routines would only work if F was the name of the main database file. 3579 ** When the F parameter is the name of the rollback journal or WAL file, 3580 ** it has access to all the same query parameters as were found on the 3581 ** main database file. 3582 ** 3583 ** See the [URI filename] documentation for additional information. 3584 */ 3585 SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam); 3586 SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault); 3587 SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64); 3588 SQLITE_API const char *sqlite3_uri_key(const char *zFilename, int N); 3589 3590 /* 3591 ** CAPI3REF: Translate filenames 3592 ** 3593 ** These routines are available to [VFS|custom VFS implementations] for 3594 ** translating filenames between the main database file, the journal file, 3595 ** and the WAL file. 3596 ** 3597 ** If F is the name of an sqlite database file, journal file, or WAL file 3598 ** passed by the SQLite core into the VFS, then sqlite3_filename_database(F) 3599 ** returns the name of the corresponding database file. 3600 ** 3601 ** If F is the name of an sqlite database file, journal file, or WAL file 3602 ** passed by the SQLite core into the VFS, or if F is a database filename 3603 ** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F) 3604 ** returns the name of the corresponding rollback journal file. 3605 ** 3606 ** If F is the name of an sqlite database file, journal file, or WAL file 3607 ** that was passed by the SQLite core into the VFS, or if F is a database 3608 ** filename obtained from [sqlite3_db_filename()], then 3609 ** sqlite3_filename_wal(F) returns the name of the corresponding 3610 ** WAL file. 3611 ** 3612 ** In all of the above, if F is not the name of a database, journal or WAL 3613 ** filename passed into the VFS from the SQLite core and F is not the 3614 ** return value from [sqlite3_db_filename()], then the result is 3615 ** undefined and is likely a memory access violation. 3616 */ 3617 SQLITE_API const char *sqlite3_filename_database(const char*); 3618 SQLITE_API const char *sqlite3_filename_journal(const char*); 3619 SQLITE_API const char *sqlite3_filename_wal(const char*); 3620 3621 3622 /* 3623 ** CAPI3REF: Error Codes And Messages 3624 ** METHOD: sqlite3 3625 ** 3626 ** ^If the most recent sqlite3_* API call associated with 3627 ** [database connection] D failed, then the sqlite3_errcode(D) interface 3628 ** returns the numeric [result code] or [extended result code] for that 3629 ** API call. 3630 ** ^The sqlite3_extended_errcode() 3631 ** interface is the same except that it always returns the 3632 ** [extended result code] even when extended result codes are 3633 ** disabled. 3634 ** 3635 ** The values returned by sqlite3_errcode() and/or 3636 ** sqlite3_extended_errcode() might change with each API call. 3637 ** Except, there are some interfaces that are guaranteed to never 3638 ** change the value of the error code. The error-code preserving 3639 ** interfaces are: 3640 ** 3641 ** <ul> 3642 ** <li> sqlite3_errcode() 3643 ** <li> sqlite3_extended_errcode() 3644 ** <li> sqlite3_errmsg() 3645 ** <li> sqlite3_errmsg16() 3646 ** </ul> 3647 ** 3648 ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language 3649 ** text that describes the error, as either UTF-8 or UTF-16 respectively. 3650 ** ^(Memory to hold the error message string is managed internally. 3651 ** The application does not need to worry about freeing the result. 3652 ** However, the error string might be overwritten or deallocated by 3653 ** subsequent calls to other SQLite interface functions.)^ 3654 ** 3655 ** ^The sqlite3_errstr() interface returns the English-language text 3656 ** that describes the [result code], as UTF-8. 3657 ** ^(Memory to hold the error message string is managed internally 3658 ** and must not be freed by the application)^. 3659 ** 3660 ** When the serialized [threading mode] is in use, it might be the 3661 ** case that a second error occurs on a separate thread in between 3662 ** the time of the first error and the call to these interfaces. 3663 ** When that happens, the second error will be reported since these 3664 ** interfaces always report the most recent result. To avoid 3665 ** this, each thread can obtain exclusive use of the [database connection] D 3666 ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning 3667 ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after 3668 ** all calls to the interfaces listed here are completed. 3669 ** 3670 ** If an interface fails with SQLITE_MISUSE, that means the interface 3671 ** was invoked incorrectly by the application. In that case, the 3672 ** error code and message may or may not be set. 3673 */ 3674 SQLITE_API int sqlite3_errcode(sqlite3 *db); 3675 SQLITE_API int sqlite3_extended_errcode(sqlite3 *db); 3676 SQLITE_API const char *sqlite3_errmsg(sqlite3*); 3677 SQLITE_API const void *sqlite3_errmsg16(sqlite3*); 3678 SQLITE_API const char *sqlite3_errstr(int); 3679 3680 /* 3681 ** CAPI3REF: Prepared Statement Object 3682 ** KEYWORDS: {prepared statement} {prepared statements} 3683 ** 3684 ** An instance of this object represents a single SQL statement that 3685 ** has been compiled into binary form and is ready to be evaluated. 3686 ** 3687 ** Think of each SQL statement as a separate computer program. The 3688 ** original SQL text is source code. A prepared statement object 3689 ** is the compiled object code. All SQL must be converted into a 3690 ** prepared statement before it can be run. 3691 ** 3692 ** The life-cycle of a prepared statement object usually goes like this: 3693 ** 3694 ** <ol> 3695 ** <li> Create the prepared statement object using [sqlite3_prepare_v2()]. 3696 ** <li> Bind values to [parameters] using the sqlite3_bind_*() 3697 ** interfaces. 3698 ** <li> Run the SQL by calling [sqlite3_step()] one or more times. 3699 ** <li> Reset the prepared statement using [sqlite3_reset()] then go back 3700 ** to step 2. Do this zero or more times. 3701 ** <li> Destroy the object using [sqlite3_finalize()]. 3702 ** </ol> 3703 */ 3704 typedef struct sqlite3_stmt sqlite3_stmt; 3705 3706 /* 3707 ** CAPI3REF: Run-time Limits 3708 ** METHOD: sqlite3 3709 ** 3710 ** ^(This interface allows the size of various constructs to be limited 3711 ** on a connection by connection basis. The first parameter is the 3712 ** [database connection] whose limit is to be set or queried. The 3713 ** second parameter is one of the [limit categories] that define a 3714 ** class of constructs to be size limited. The third parameter is the 3715 ** new limit for that construct.)^ 3716 ** 3717 ** ^If the new limit is a negative number, the limit is unchanged. 3718 ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 3719 ** [limits | hard upper bound] 3720 ** set at compile-time by a C preprocessor macro called 3721 ** [limits | SQLITE_MAX_<i>NAME</i>]. 3722 ** (The "_LIMIT_" in the name is changed to "_MAX_".))^ 3723 ** ^Attempts to increase a limit above its hard upper bound are 3724 ** silently truncated to the hard upper bound. 3725 ** 3726 ** ^Regardless of whether or not the limit was changed, the 3727 ** [sqlite3_limit()] interface returns the prior value of the limit. 3728 ** ^Hence, to find the current value of a limit without changing it, 3729 ** simply invoke this interface with the third parameter set to -1. 3730 ** 3731 ** Run-time limits are intended for use in applications that manage 3732 ** both their own internal database and also databases that are controlled 3733 ** by untrusted external sources. An example application might be a 3734 ** web browser that has its own databases for storing history and 3735 ** separate databases controlled by JavaScript applications downloaded 3736 ** off the Internet. The internal databases can be given the 3737 ** large, default limits. Databases managed by external sources can 3738 ** be given much smaller limits designed to prevent a denial of service 3739 ** attack. Developers might also want to use the [sqlite3_set_authorizer()] 3740 ** interface to further control untrusted SQL. The size of the database 3741 ** created by an untrusted script can be contained using the 3742 ** [max_page_count] [PRAGMA]. 3743 ** 3744 ** New run-time limit categories may be added in future releases. 3745 */ 3746 SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal); 3747 3748 /* 3749 ** CAPI3REF: Run-Time Limit Categories 3750 ** KEYWORDS: {limit category} {*limit categories} 3751 ** 3752 ** These constants define various performance limits 3753 ** that can be lowered at run-time using [sqlite3_limit()]. 3754 ** The synopsis of the meanings of the various limits is shown below. 3755 ** Additional information is available at [limits | Limits in SQLite]. 3756 ** 3757 ** <dl> 3758 ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt> 3759 ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^ 3760 ** 3761 ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt> 3762 ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^ 3763 ** 3764 ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt> 3765 ** <dd>The maximum number of columns in a table definition or in the 3766 ** result set of a [SELECT] or the maximum number of columns in an index 3767 ** or in an ORDER BY or GROUP BY clause.</dd>)^ 3768 ** 3769 ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt> 3770 ** <dd>The maximum depth of the parse tree on any expression.</dd>)^ 3771 ** 3772 ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> 3773 ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^ 3774 ** 3775 ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt> 3776 ** <dd>The maximum number of instructions in a virtual machine program 3777 ** used to implement an SQL statement. If [sqlite3_prepare_v2()] or 3778 ** the equivalent tries to allocate space for more than this many opcodes 3779 ** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^ 3780 ** 3781 ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt> 3782 ** <dd>The maximum number of arguments on a function.</dd>)^ 3783 ** 3784 ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt> 3785 ** <dd>The maximum number of [ATTACH | attached databases].)^</dd> 3786 ** 3787 ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] 3788 ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> 3789 ** <dd>The maximum length of the pattern argument to the [LIKE] or 3790 ** [GLOB] operators.</dd>)^ 3791 ** 3792 ** [[SQLITE_LIMIT_VARIABLE_NUMBER]] 3793 ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> 3794 ** <dd>The maximum index number of any [parameter] in an SQL statement.)^ 3795 ** 3796 ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt> 3797 ** <dd>The maximum depth of recursion for triggers.</dd>)^ 3798 ** 3799 ** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt> 3800 ** <dd>The maximum number of auxiliary worker threads that a single 3801 ** [prepared statement] may start.</dd>)^ 3802 ** </dl> 3803 */ 3804 #define SQLITE_LIMIT_LENGTH 0 3805 #define SQLITE_LIMIT_SQL_LENGTH 1 3806 #define SQLITE_LIMIT_COLUMN 2 3807 #define SQLITE_LIMIT_EXPR_DEPTH 3 3808 #define SQLITE_LIMIT_COMPOUND_SELECT 4 3809 #define SQLITE_LIMIT_VDBE_OP 5 3810 #define SQLITE_LIMIT_FUNCTION_ARG 6 3811 #define SQLITE_LIMIT_ATTACHED 7 3812 #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 3813 #define SQLITE_LIMIT_VARIABLE_NUMBER 9 3814 #define SQLITE_LIMIT_TRIGGER_DEPTH 10 3815 #define SQLITE_LIMIT_WORKER_THREADS 11 3816 3817 /* 3818 ** CAPI3REF: Prepare Flags 3819 ** 3820 ** These constants define various flags that can be passed into 3821 ** "prepFlags" parameter of the [sqlite3_prepare_v3()] and 3822 ** [sqlite3_prepare16_v3()] interfaces. 3823 ** 3824 ** New flags may be added in future releases of SQLite. 3825 ** 3826 ** <dl> 3827 ** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt> 3828 ** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner 3829 ** that the prepared statement will be retained for a long time and 3830 ** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()] 3831 ** and [sqlite3_prepare16_v3()] assume that the prepared statement will 3832 ** be used just once or at most a few times and then destroyed using 3833 ** [sqlite3_finalize()] relatively soon. The current implementation acts 3834 ** on this hint by avoiding the use of [lookaside memory] so as not to 3835 ** deplete the limited store of lookaside memory. Future versions of 3836 ** SQLite may act on this hint differently. 3837 ** 3838 ** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt> 3839 ** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used 3840 ** to be required for any prepared statement that wanted to use the 3841 ** [sqlite3_normalized_sql()] interface. However, the 3842 ** [sqlite3_normalized_sql()] interface is now available to all 3843 ** prepared statements, regardless of whether or not they use this 3844 ** flag. 3845 ** 3846 ** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt> 3847 ** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler 3848 ** to return an error (error code SQLITE_ERROR) if the statement uses 3849 ** any virtual tables. 3850 ** </dl> 3851 */ 3852 #define SQLITE_PREPARE_PERSISTENT 0x01 3853 #define SQLITE_PREPARE_NORMALIZE 0x02 3854 #define SQLITE_PREPARE_NO_VTAB 0x04 3855 3856 /* 3857 ** CAPI3REF: Compiling An SQL Statement 3858 ** KEYWORDS: {SQL statement compiler} 3859 ** METHOD: sqlite3 3860 ** CONSTRUCTOR: sqlite3_stmt 3861 ** 3862 ** To execute an SQL statement, it must first be compiled into a byte-code 3863 ** program using one of these routines. Or, in other words, these routines 3864 ** are constructors for the [prepared statement] object. 3865 ** 3866 ** The preferred routine to use is [sqlite3_prepare_v2()]. The 3867 ** [sqlite3_prepare()] interface is legacy and should be avoided. 3868 ** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used 3869 ** for special purposes. 3870 ** 3871 ** The use of the UTF-8 interfaces is preferred, as SQLite currently 3872 ** does all parsing using UTF-8. The UTF-16 interfaces are provided 3873 ** as a convenience. The UTF-16 interfaces work by converting the 3874 ** input text into UTF-8, then invoking the corresponding UTF-8 interface. 3875 ** 3876 ** The first argument, "db", is a [database connection] obtained from a 3877 ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or 3878 ** [sqlite3_open16()]. The database connection must not have been closed. 3879 ** 3880 ** The second argument, "zSql", is the statement to be compiled, encoded 3881 ** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(), 3882 ** and sqlite3_prepare_v3() 3883 ** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(), 3884 ** and sqlite3_prepare16_v3() use UTF-16. 3885 ** 3886 ** ^If the nByte argument is negative, then zSql is read up to the 3887 ** first zero terminator. ^If nByte is positive, then it is the 3888 ** number of bytes read from zSql. ^If nByte is zero, then no prepared 3889 ** statement is generated. 3890 ** If the caller knows that the supplied string is nul-terminated, then 3891 ** there is a small performance advantage to passing an nByte parameter that 3892 ** is the number of bytes in the input string <i>including</i> 3893 ** the nul-terminator. 3894 ** 3895 ** ^If pzTail is not NULL then *pzTail is made to point to the first byte 3896 ** past the end of the first SQL statement in zSql. These routines only 3897 ** compile the first statement in zSql, so *pzTail is left pointing to 3898 ** what remains uncompiled. 3899 ** 3900 ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be 3901 ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set 3902 ** to NULL. ^If the input text contains no SQL (if the input is an empty 3903 ** string or a comment) then *ppStmt is set to NULL. 3904 ** The calling procedure is responsible for deleting the compiled 3905 ** SQL statement using [sqlite3_finalize()] after it has finished with it. 3906 ** ppStmt may not be NULL. 3907 ** 3908 ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; 3909 ** otherwise an [error code] is returned. 3910 ** 3911 ** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(), 3912 ** and sqlite3_prepare16_v3() interfaces are recommended for all new programs. 3913 ** The older interfaces (sqlite3_prepare() and sqlite3_prepare16()) 3914 ** are retained for backwards compatibility, but their use is discouraged. 3915 ** ^In the "vX" interfaces, the prepared statement 3916 ** that is returned (the [sqlite3_stmt] object) contains a copy of the 3917 ** original SQL text. This causes the [sqlite3_step()] interface to 3918 ** behave differently in three ways: 3919 ** 3920 ** <ol> 3921 ** <li> 3922 ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it 3923 ** always used to do, [sqlite3_step()] will automatically recompile the SQL 3924 ** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY] 3925 ** retries will occur before sqlite3_step() gives up and returns an error. 3926 ** </li> 3927 ** 3928 ** <li> 3929 ** ^When an error occurs, [sqlite3_step()] will return one of the detailed 3930 ** [error codes] or [extended error codes]. ^The legacy behavior was that 3931 ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code 3932 ** and the application would have to make a second call to [sqlite3_reset()] 3933 ** in order to find the underlying cause of the problem. With the "v2" prepare 3934 ** interfaces, the underlying reason for the error is returned immediately. 3935 ** </li> 3936 ** 3937 ** <li> 3938 ** ^If the specific value bound to a [parameter | host parameter] in the 3939 ** WHERE clause might influence the choice of query plan for a statement, 3940 ** then the statement will be automatically recompiled, as if there had been 3941 ** a schema change, on the first [sqlite3_step()] call following any change 3942 ** to the [sqlite3_bind_text | bindings] of that [parameter]. 3943 ** ^The specific value of a WHERE-clause [parameter] might influence the 3944 ** choice of query plan if the parameter is the left-hand side of a [LIKE] 3945 ** or [GLOB] operator or if the parameter is compared to an indexed column 3946 ** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled. 3947 ** </li> 3948 ** </ol> 3949 ** 3950 ** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having 3951 ** the extra prepFlags parameter, which is a bit array consisting of zero or 3952 ** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The 3953 ** sqlite3_prepare_v2() interface works exactly the same as 3954 ** sqlite3_prepare_v3() with a zero prepFlags parameter. 3955 */ 3956 SQLITE_API int sqlite3_prepare( 3957 sqlite3 *db, /* Database handle */ 3958 const char *zSql, /* SQL statement, UTF-8 encoded */ 3959 int nByte, /* Maximum length of zSql in bytes. */ 3960 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 3961 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 3962 ); 3963 SQLITE_API int sqlite3_prepare_v2( 3964 sqlite3 *db, /* Database handle */ 3965 const char *zSql, /* SQL statement, UTF-8 encoded */ 3966 int nByte, /* Maximum length of zSql in bytes. */ 3967 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 3968 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 3969 ); 3970 SQLITE_API int sqlite3_prepare_v3( 3971 sqlite3 *db, /* Database handle */ 3972 const char *zSql, /* SQL statement, UTF-8 encoded */ 3973 int nByte, /* Maximum length of zSql in bytes. */ 3974 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 3975 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 3976 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 3977 ); 3978 SQLITE_API int sqlite3_prepare16( 3979 sqlite3 *db, /* Database handle */ 3980 const void *zSql, /* SQL statement, UTF-16 encoded */ 3981 int nByte, /* Maximum length of zSql in bytes. */ 3982 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 3983 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 3984 ); 3985 SQLITE_API int sqlite3_prepare16_v2( 3986 sqlite3 *db, /* Database handle */ 3987 const void *zSql, /* SQL statement, UTF-16 encoded */ 3988 int nByte, /* Maximum length of zSql in bytes. */ 3989 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 3990 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 3991 ); 3992 SQLITE_API int sqlite3_prepare16_v3( 3993 sqlite3 *db, /* Database handle */ 3994 const void *zSql, /* SQL statement, UTF-16 encoded */ 3995 int nByte, /* Maximum length of zSql in bytes. */ 3996 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 3997 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 3998 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 3999 ); 4000 4001 /* 4002 ** CAPI3REF: Retrieving Statement SQL 4003 ** METHOD: sqlite3_stmt 4004 ** 4005 ** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8 4006 ** SQL text used to create [prepared statement] P if P was 4007 ** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], 4008 ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 4009 ** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8 4010 ** string containing the SQL text of prepared statement P with 4011 ** [bound parameters] expanded. 4012 ** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8 4013 ** string containing the normalized SQL text of prepared statement P. The 4014 ** semantics used to normalize a SQL statement are unspecified and subject 4015 ** to change. At a minimum, literal values will be replaced with suitable 4016 ** placeholders. 4017 ** 4018 ** ^(For example, if a prepared statement is created using the SQL 4019 ** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345 4020 ** and parameter :xyz is unbound, then sqlite3_sql() will return 4021 ** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql() 4022 ** will return "SELECT 2345,NULL".)^ 4023 ** 4024 ** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory 4025 ** is available to hold the result, or if the result would exceed the 4026 ** the maximum string length determined by the [SQLITE_LIMIT_LENGTH]. 4027 ** 4028 ** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of 4029 ** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time 4030 ** option causes sqlite3_expanded_sql() to always return NULL. 4031 ** 4032 ** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P) 4033 ** are managed by SQLite and are automatically freed when the prepared 4034 ** statement is finalized. 4035 ** ^The string returned by sqlite3_expanded_sql(P), on the other hand, 4036 ** is obtained from [sqlite3_malloc()] and must be free by the application 4037 ** by passing it to [sqlite3_free()]. 4038 */ 4039 SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt); 4040 SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt); 4041 SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt); 4042 4043 /* 4044 ** CAPI3REF: Determine If An SQL Statement Writes The Database 4045 ** METHOD: sqlite3_stmt 4046 ** 4047 ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if 4048 ** and only if the [prepared statement] X makes no direct changes to 4049 ** the content of the database file. 4050 ** 4051 ** Note that [application-defined SQL functions] or 4052 ** [virtual tables] might change the database indirectly as a side effect. 4053 ** ^(For example, if an application defines a function "eval()" that 4054 ** calls [sqlite3_exec()], then the following SQL statement would 4055 ** change the database file through side-effects: 4056 ** 4057 ** <blockquote><pre> 4058 ** SELECT eval('DELETE FROM t1') FROM t2; 4059 ** </pre></blockquote> 4060 ** 4061 ** But because the [SELECT] statement does not change the database file 4062 ** directly, sqlite3_stmt_readonly() would still return true.)^ 4063 ** 4064 ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], 4065 ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, 4066 ** since the statements themselves do not actually modify the database but 4067 ** rather they control the timing of when other statements modify the 4068 ** database. ^The [ATTACH] and [DETACH] statements also cause 4069 ** sqlite3_stmt_readonly() to return true since, while those statements 4070 ** change the configuration of a database connection, they do not make 4071 ** changes to the content of the database files on disk. 4072 ** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since 4073 ** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and 4074 ** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so 4075 ** sqlite3_stmt_readonly() returns false for those commands. 4076 */ 4077 SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt); 4078 4079 /* 4080 ** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement 4081 ** METHOD: sqlite3_stmt 4082 ** 4083 ** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the 4084 ** prepared statement S is an EXPLAIN statement, or 2 if the 4085 ** statement S is an EXPLAIN QUERY PLAN. 4086 ** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is 4087 ** an ordinary statement or a NULL pointer. 4088 */ 4089 SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt); 4090 4091 /* 4092 ** CAPI3REF: Determine If A Prepared Statement Has Been Reset 4093 ** METHOD: sqlite3_stmt 4094 ** 4095 ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the 4096 ** [prepared statement] S has been stepped at least once using 4097 ** [sqlite3_step(S)] but has neither run to completion (returned 4098 ** [SQLITE_DONE] from [sqlite3_step(S)]) nor 4099 ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) 4100 ** interface returns false if S is a NULL pointer. If S is not a 4101 ** NULL pointer and is not a pointer to a valid [prepared statement] 4102 ** object, then the behavior is undefined and probably undesirable. 4103 ** 4104 ** This interface can be used in combination [sqlite3_next_stmt()] 4105 ** to locate all prepared statements associated with a database 4106 ** connection that are in need of being reset. This can be used, 4107 ** for example, in diagnostic routines to search for prepared 4108 ** statements that are holding a transaction open. 4109 */ 4110 SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*); 4111 4112 /* 4113 ** CAPI3REF: Dynamically Typed Value Object 4114 ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} 4115 ** 4116 ** SQLite uses the sqlite3_value object to represent all values 4117 ** that can be stored in a database table. SQLite uses dynamic typing 4118 ** for the values it stores. ^Values stored in sqlite3_value objects 4119 ** can be integers, floating point values, strings, BLOBs, or NULL. 4120 ** 4121 ** An sqlite3_value object may be either "protected" or "unprotected". 4122 ** Some interfaces require a protected sqlite3_value. Other interfaces 4123 ** will accept either a protected or an unprotected sqlite3_value. 4124 ** Every interface that accepts sqlite3_value arguments specifies 4125 ** whether or not it requires a protected sqlite3_value. The 4126 ** [sqlite3_value_dup()] interface can be used to construct a new 4127 ** protected sqlite3_value from an unprotected sqlite3_value. 4128 ** 4129 ** The terms "protected" and "unprotected" refer to whether or not 4130 ** a mutex is held. An internal mutex is held for a protected 4131 ** sqlite3_value object but no mutex is held for an unprotected 4132 ** sqlite3_value object. If SQLite is compiled to be single-threaded 4133 ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) 4134 ** or if SQLite is run in one of reduced mutex modes 4135 ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] 4136 ** then there is no distinction between protected and unprotected 4137 ** sqlite3_value objects and they can be used interchangeably. However, 4138 ** for maximum code portability it is recommended that applications 4139 ** still make the distinction between protected and unprotected 4140 ** sqlite3_value objects even when not strictly required. 4141 ** 4142 ** ^The sqlite3_value objects that are passed as parameters into the 4143 ** implementation of [application-defined SQL functions] are protected. 4144 ** ^The sqlite3_value object returned by 4145 ** [sqlite3_column_value()] is unprotected. 4146 ** Unprotected sqlite3_value objects may only be used as arguments 4147 ** to [sqlite3_result_value()], [sqlite3_bind_value()], and 4148 ** [sqlite3_value_dup()]. 4149 ** The [sqlite3_value_blob | sqlite3_value_type()] family of 4150 ** interfaces require protected sqlite3_value objects. 4151 */ 4152 typedef struct sqlite3_value sqlite3_value; 4153 4154 /* 4155 ** CAPI3REF: SQL Function Context Object 4156 ** 4157 ** The context in which an SQL function executes is stored in an 4158 ** sqlite3_context object. ^A pointer to an sqlite3_context object 4159 ** is always first parameter to [application-defined SQL functions]. 4160 ** The application-defined SQL function implementation will pass this 4161 ** pointer through into calls to [sqlite3_result_int | sqlite3_result()], 4162 ** [sqlite3_aggregate_context()], [sqlite3_user_data()], 4163 ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], 4164 ** and/or [sqlite3_set_auxdata()]. 4165 */ 4166 typedef struct sqlite3_context sqlite3_context; 4167 4168 /* 4169 ** CAPI3REF: Binding Values To Prepared Statements 4170 ** KEYWORDS: {host parameter} {host parameters} {host parameter name} 4171 ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} 4172 ** METHOD: sqlite3_stmt 4173 ** 4174 ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, 4175 ** literals may be replaced by a [parameter] that matches one of following 4176 ** templates: 4177 ** 4178 ** <ul> 4179 ** <li> ? 4180 ** <li> ?NNN 4181 ** <li> :VVV 4182 ** <li> @VVV 4183 ** <li> $VVV 4184 ** </ul> 4185 ** 4186 ** In the templates above, NNN represents an integer literal, 4187 ** and VVV represents an alphanumeric identifier.)^ ^The values of these 4188 ** parameters (also called "host parameter names" or "SQL parameters") 4189 ** can be set using the sqlite3_bind_*() routines defined here. 4190 ** 4191 ** ^The first argument to the sqlite3_bind_*() routines is always 4192 ** a pointer to the [sqlite3_stmt] object returned from 4193 ** [sqlite3_prepare_v2()] or its variants. 4194 ** 4195 ** ^The second argument is the index of the SQL parameter to be set. 4196 ** ^The leftmost SQL parameter has an index of 1. ^When the same named 4197 ** SQL parameter is used more than once, second and subsequent 4198 ** occurrences have the same index as the first occurrence. 4199 ** ^The index for named parameters can be looked up using the 4200 ** [sqlite3_bind_parameter_index()] API if desired. ^The index 4201 ** for "?NNN" parameters is the value of NNN. 4202 ** ^The NNN value must be between 1 and the [sqlite3_limit()] 4203 ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999). 4204 ** 4205 ** ^The third argument is the value to bind to the parameter. 4206 ** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4207 ** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter 4208 ** is ignored and the end result is the same as sqlite3_bind_null(). 4209 ** 4210 ** ^(In those routines that have a fourth argument, its value is the 4211 ** number of bytes in the parameter. To be clear: the value is the 4212 ** number of <u>bytes</u> in the value, not the number of characters.)^ 4213 ** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4214 ** is negative, then the length of the string is 4215 ** the number of bytes up to the first zero terminator. 4216 ** If the fourth parameter to sqlite3_bind_blob() is negative, then 4217 ** the behavior is undefined. 4218 ** If a non-negative fourth parameter is provided to sqlite3_bind_text() 4219 ** or sqlite3_bind_text16() or sqlite3_bind_text64() then 4220 ** that parameter must be the byte offset 4221 ** where the NUL terminator would occur assuming the string were NUL 4222 ** terminated. If any NUL characters occur at byte offsets less than 4223 ** the value of the fourth parameter then the resulting string value will 4224 ** contain embedded NULs. The result of expressions involving strings 4225 ** with embedded NULs is undefined. 4226 ** 4227 ** ^The fifth argument to the BLOB and string binding interfaces 4228 ** is a destructor used to dispose of the BLOB or 4229 ** string after SQLite has finished with it. ^The destructor is called 4230 ** to dispose of the BLOB or string even if the call to the bind API fails, 4231 ** except the destructor is not called if the third parameter is a NULL 4232 ** pointer or the fourth parameter is negative. 4233 ** ^If the fifth argument is 4234 ** the special value [SQLITE_STATIC], then SQLite assumes that the 4235 ** information is in static, unmanaged space and does not need to be freed. 4236 ** ^If the fifth argument has the value [SQLITE_TRANSIENT], then 4237 ** SQLite makes its own private copy of the data immediately, before 4238 ** the sqlite3_bind_*() routine returns. 4239 ** 4240 ** ^The sixth argument to sqlite3_bind_text64() must be one of 4241 ** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE] 4242 ** to specify the encoding of the text in the third parameter. If 4243 ** the sixth argument to sqlite3_bind_text64() is not one of the 4244 ** allowed values shown above, or if the text encoding is different 4245 ** from the encoding specified by the sixth parameter, then the behavior 4246 ** is undefined. 4247 ** 4248 ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that 4249 ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory 4250 ** (just an integer to hold its size) while it is being processed. 4251 ** Zeroblobs are intended to serve as placeholders for BLOBs whose 4252 ** content is later written using 4253 ** [sqlite3_blob_open | incremental BLOB I/O] routines. 4254 ** ^A negative value for the zeroblob results in a zero-length BLOB. 4255 ** 4256 ** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in 4257 ** [prepared statement] S to have an SQL value of NULL, but to also be 4258 ** associated with the pointer P of type T. ^D is either a NULL pointer or 4259 ** a pointer to a destructor function for P. ^SQLite will invoke the 4260 ** destructor D with a single argument of P when it is finished using 4261 ** P. The T parameter should be a static string, preferably a string 4262 ** literal. The sqlite3_bind_pointer() routine is part of the 4263 ** [pointer passing interface] added for SQLite 3.20.0. 4264 ** 4265 ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer 4266 ** for the [prepared statement] or with a prepared statement for which 4267 ** [sqlite3_step()] has been called more recently than [sqlite3_reset()], 4268 ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() 4269 ** routine is passed a [prepared statement] that has been finalized, the 4270 ** result is undefined and probably harmful. 4271 ** 4272 ** ^Bindings are not cleared by the [sqlite3_reset()] routine. 4273 ** ^Unbound parameters are interpreted as NULL. 4274 ** 4275 ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an 4276 ** [error code] if anything goes wrong. 4277 ** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB 4278 ** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or 4279 ** [SQLITE_MAX_LENGTH]. 4280 ** ^[SQLITE_RANGE] is returned if the parameter 4281 ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. 4282 ** 4283 ** See also: [sqlite3_bind_parameter_count()], 4284 ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. 4285 */ 4286 SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); 4287 SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64, 4288 void(*)(void*)); 4289 SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double); 4290 SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int); 4291 SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); 4292 SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int); 4293 SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*)); 4294 SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); 4295 SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64, 4296 void(*)(void*), unsigned char encoding); 4297 SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); 4298 SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*)); 4299 SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); 4300 SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64); 4301 4302 /* 4303 ** CAPI3REF: Number Of SQL Parameters 4304 ** METHOD: sqlite3_stmt 4305 ** 4306 ** ^This routine can be used to find the number of [SQL parameters] 4307 ** in a [prepared statement]. SQL parameters are tokens of the 4308 ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as 4309 ** placeholders for values that are [sqlite3_bind_blob | bound] 4310 ** to the parameters at a later time. 4311 ** 4312 ** ^(This routine actually returns the index of the largest (rightmost) 4313 ** parameter. For all forms except ?NNN, this will correspond to the 4314 ** number of unique parameters. If parameters of the ?NNN form are used, 4315 ** there may be gaps in the list.)^ 4316 ** 4317 ** See also: [sqlite3_bind_blob|sqlite3_bind()], 4318 ** [sqlite3_bind_parameter_name()], and 4319 ** [sqlite3_bind_parameter_index()]. 4320 */ 4321 SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*); 4322 4323 /* 4324 ** CAPI3REF: Name Of A Host Parameter 4325 ** METHOD: sqlite3_stmt 4326 ** 4327 ** ^The sqlite3_bind_parameter_name(P,N) interface returns 4328 ** the name of the N-th [SQL parameter] in the [prepared statement] P. 4329 ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" 4330 ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" 4331 ** respectively. 4332 ** In other words, the initial ":" or "$" or "@" or "?" 4333 ** is included as part of the name.)^ 4334 ** ^Parameters of the form "?" without a following integer have no name 4335 ** and are referred to as "nameless" or "anonymous parameters". 4336 ** 4337 ** ^The first host parameter has an index of 1, not 0. 4338 ** 4339 ** ^If the value N is out of range or if the N-th parameter is 4340 ** nameless, then NULL is returned. ^The returned string is 4341 ** always in UTF-8 encoding even if the named parameter was 4342 ** originally specified as UTF-16 in [sqlite3_prepare16()], 4343 ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 4344 ** 4345 ** See also: [sqlite3_bind_blob|sqlite3_bind()], 4346 ** [sqlite3_bind_parameter_count()], and 4347 ** [sqlite3_bind_parameter_index()]. 4348 */ 4349 SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); 4350 4351 /* 4352 ** CAPI3REF: Index Of A Parameter With A Given Name 4353 ** METHOD: sqlite3_stmt 4354 ** 4355 ** ^Return the index of an SQL parameter given its name. ^The 4356 ** index value returned is suitable for use as the second 4357 ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero 4358 ** is returned if no matching parameter is found. ^The parameter 4359 ** name must be given in UTF-8 even if the original statement 4360 ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or 4361 ** [sqlite3_prepare16_v3()]. 4362 ** 4363 ** See also: [sqlite3_bind_blob|sqlite3_bind()], 4364 ** [sqlite3_bind_parameter_count()], and 4365 ** [sqlite3_bind_parameter_name()]. 4366 */ 4367 SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); 4368 4369 /* 4370 ** CAPI3REF: Reset All Bindings On A Prepared Statement 4371 ** METHOD: sqlite3_stmt 4372 ** 4373 ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset 4374 ** the [sqlite3_bind_blob | bindings] on a [prepared statement]. 4375 ** ^Use this routine to reset all host parameters to NULL. 4376 */ 4377 SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*); 4378 4379 /* 4380 ** CAPI3REF: Number Of Columns In A Result Set 4381 ** METHOD: sqlite3_stmt 4382 ** 4383 ** ^Return the number of columns in the result set returned by the 4384 ** [prepared statement]. ^If this routine returns 0, that means the 4385 ** [prepared statement] returns no data (for example an [UPDATE]). 4386 ** ^However, just because this routine returns a positive number does not 4387 ** mean that one or more rows of data will be returned. ^A SELECT statement 4388 ** will always have a positive sqlite3_column_count() but depending on the 4389 ** WHERE clause constraints and the table content, it might return no rows. 4390 ** 4391 ** See also: [sqlite3_data_count()] 4392 */ 4393 SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt); 4394 4395 /* 4396 ** CAPI3REF: Column Names In A Result Set 4397 ** METHOD: sqlite3_stmt 4398 ** 4399 ** ^These routines return the name assigned to a particular column 4400 ** in the result set of a [SELECT] statement. ^The sqlite3_column_name() 4401 ** interface returns a pointer to a zero-terminated UTF-8 string 4402 ** and sqlite3_column_name16() returns a pointer to a zero-terminated 4403 ** UTF-16 string. ^The first parameter is the [prepared statement] 4404 ** that implements the [SELECT] statement. ^The second parameter is the 4405 ** column number. ^The leftmost column is number 0. 4406 ** 4407 ** ^The returned string pointer is valid until either the [prepared statement] 4408 ** is destroyed by [sqlite3_finalize()] or until the statement is automatically 4409 ** reprepared by the first call to [sqlite3_step()] for a particular run 4410 ** or until the next call to 4411 ** sqlite3_column_name() or sqlite3_column_name16() on the same column. 4412 ** 4413 ** ^If sqlite3_malloc() fails during the processing of either routine 4414 ** (for example during a conversion from UTF-8 to UTF-16) then a 4415 ** NULL pointer is returned. 4416 ** 4417 ** ^The name of a result column is the value of the "AS" clause for 4418 ** that column, if there is an AS clause. If there is no AS clause 4419 ** then the name of the column is unspecified and may change from 4420 ** one release of SQLite to the next. 4421 */ 4422 SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N); 4423 SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N); 4424 4425 /* 4426 ** CAPI3REF: Source Of Data In A Query Result 4427 ** METHOD: sqlite3_stmt 4428 ** 4429 ** ^These routines provide a means to determine the database, table, and 4430 ** table column that is the origin of a particular result column in 4431 ** [SELECT] statement. 4432 ** ^The name of the database or table or column can be returned as 4433 ** either a UTF-8 or UTF-16 string. ^The _database_ routines return 4434 ** the database name, the _table_ routines return the table name, and 4435 ** the origin_ routines return the column name. 4436 ** ^The returned string is valid until the [prepared statement] is destroyed 4437 ** using [sqlite3_finalize()] or until the statement is automatically 4438 ** reprepared by the first call to [sqlite3_step()] for a particular run 4439 ** or until the same information is requested 4440 ** again in a different encoding. 4441 ** 4442 ** ^The names returned are the original un-aliased names of the 4443 ** database, table, and column. 4444 ** 4445 ** ^The first argument to these interfaces is a [prepared statement]. 4446 ** ^These functions return information about the Nth result column returned by 4447 ** the statement, where N is the second function argument. 4448 ** ^The left-most column is column 0 for these routines. 4449 ** 4450 ** ^If the Nth column returned by the statement is an expression or 4451 ** subquery and is not a column value, then all of these functions return 4452 ** NULL. ^These routines might also return NULL if a memory allocation error 4453 ** occurs. ^Otherwise, they return the name of the attached database, table, 4454 ** or column that query result column was extracted from. 4455 ** 4456 ** ^As with all other SQLite APIs, those whose names end with "16" return 4457 ** UTF-16 encoded strings and the other functions return UTF-8. 4458 ** 4459 ** ^These APIs are only available if the library was compiled with the 4460 ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. 4461 ** 4462 ** If two or more threads call one or more 4463 ** [sqlite3_column_database_name | column metadata interfaces] 4464 ** for the same [prepared statement] and result column 4465 ** at the same time then the results are undefined. 4466 */ 4467 SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int); 4468 SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int); 4469 SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int); 4470 SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int); 4471 SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int); 4472 SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); 4473 4474 /* 4475 ** CAPI3REF: Declared Datatype Of A Query Result 4476 ** METHOD: sqlite3_stmt 4477 ** 4478 ** ^(The first parameter is a [prepared statement]. 4479 ** If this statement is a [SELECT] statement and the Nth column of the 4480 ** returned result set of that [SELECT] is a table column (not an 4481 ** expression or subquery) then the declared type of the table 4482 ** column is returned.)^ ^If the Nth column of the result set is an 4483 ** expression or subquery, then a NULL pointer is returned. 4484 ** ^The returned string is always UTF-8 encoded. 4485 ** 4486 ** ^(For example, given the database schema: 4487 ** 4488 ** CREATE TABLE t1(c1 VARIANT); 4489 ** 4490 ** and the following statement to be compiled: 4491 ** 4492 ** SELECT c1 + 1, c1 FROM t1; 4493 ** 4494 ** this routine would return the string "VARIANT" for the second result 4495 ** column (i==1), and a NULL pointer for the first result column (i==0).)^ 4496 ** 4497 ** ^SQLite uses dynamic run-time typing. ^So just because a column 4498 ** is declared to contain a particular type does not mean that the 4499 ** data stored in that column is of the declared type. SQLite is 4500 ** strongly typed, but the typing is dynamic not static. ^Type 4501 ** is associated with individual values, not with the containers 4502 ** used to hold those values. 4503 */ 4504 SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int); 4505 SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int); 4506 4507 /* 4508 ** CAPI3REF: Evaluate An SQL Statement 4509 ** METHOD: sqlite3_stmt 4510 ** 4511 ** After a [prepared statement] has been prepared using any of 4512 ** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()], 4513 ** or [sqlite3_prepare16_v3()] or one of the legacy 4514 ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function 4515 ** must be called one or more times to evaluate the statement. 4516 ** 4517 ** The details of the behavior of the sqlite3_step() interface depend 4518 ** on whether the statement was prepared using the newer "vX" interfaces 4519 ** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()], 4520 ** [sqlite3_prepare16_v2()] or the older legacy 4521 ** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the 4522 ** new "vX" interface is recommended for new applications but the legacy 4523 ** interface will continue to be supported. 4524 ** 4525 ** ^In the legacy interface, the return value will be either [SQLITE_BUSY], 4526 ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. 4527 ** ^With the "v2" interface, any of the other [result codes] or 4528 ** [extended result codes] might be returned as well. 4529 ** 4530 ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the 4531 ** database locks it needs to do its job. ^If the statement is a [COMMIT] 4532 ** or occurs outside of an explicit transaction, then you can retry the 4533 ** statement. If the statement is not a [COMMIT] and occurs within an 4534 ** explicit transaction then you should rollback the transaction before 4535 ** continuing. 4536 ** 4537 ** ^[SQLITE_DONE] means that the statement has finished executing 4538 ** successfully. sqlite3_step() should not be called again on this virtual 4539 ** machine without first calling [sqlite3_reset()] to reset the virtual 4540 ** machine back to its initial state. 4541 ** 4542 ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] 4543 ** is returned each time a new row of data is ready for processing by the 4544 ** caller. The values may be accessed using the [column access functions]. 4545 ** sqlite3_step() is called again to retrieve the next row of data. 4546 ** 4547 ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint 4548 ** violation) has occurred. sqlite3_step() should not be called again on 4549 ** the VM. More information may be found by calling [sqlite3_errmsg()]. 4550 ** ^With the legacy interface, a more specific error code (for example, 4551 ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) 4552 ** can be obtained by calling [sqlite3_reset()] on the 4553 ** [prepared statement]. ^In the "v2" interface, 4554 ** the more specific error code is returned directly by sqlite3_step(). 4555 ** 4556 ** [SQLITE_MISUSE] means that the this routine was called inappropriately. 4557 ** Perhaps it was called on a [prepared statement] that has 4558 ** already been [sqlite3_finalize | finalized] or on one that had 4559 ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could 4560 ** be the case that the same database connection is being used by two or 4561 ** more threads at the same moment in time. 4562 ** 4563 ** For all versions of SQLite up to and including 3.6.23.1, a call to 4564 ** [sqlite3_reset()] was required after sqlite3_step() returned anything 4565 ** other than [SQLITE_ROW] before any subsequent invocation of 4566 ** sqlite3_step(). Failure to reset the prepared statement using 4567 ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from 4568 ** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1], 4569 ** sqlite3_step() began 4570 ** calling [sqlite3_reset()] automatically in this circumstance rather 4571 ** than returning [SQLITE_MISUSE]. This is not considered a compatibility 4572 ** break because any application that ever receives an SQLITE_MISUSE error 4573 ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option 4574 ** can be used to restore the legacy behavior. 4575 ** 4576 ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() 4577 ** API always returns a generic error code, [SQLITE_ERROR], following any 4578 ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call 4579 ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the 4580 ** specific [error codes] that better describes the error. 4581 ** We admit that this is a goofy design. The problem has been fixed 4582 ** with the "v2" interface. If you prepare all of your SQL statements 4583 ** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()] 4584 ** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead 4585 ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, 4586 ** then the more specific [error codes] are returned directly 4587 ** by sqlite3_step(). The use of the "vX" interfaces is recommended. 4588 */ 4589 SQLITE_API int sqlite3_step(sqlite3_stmt*); 4590 4591 /* 4592 ** CAPI3REF: Number of columns in a result set 4593 ** METHOD: sqlite3_stmt 4594 ** 4595 ** ^The sqlite3_data_count(P) interface returns the number of columns in the 4596 ** current row of the result set of [prepared statement] P. 4597 ** ^If prepared statement P does not have results ready to return 4598 ** (via calls to the [sqlite3_column_int | sqlite3_column()] family of 4599 ** interfaces) then sqlite3_data_count(P) returns 0. 4600 ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. 4601 ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to 4602 ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) 4603 ** will return non-zero if previous call to [sqlite3_step](P) returned 4604 ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] 4605 ** where it always returns zero since each step of that multi-step 4606 ** pragma returns 0 columns of data. 4607 ** 4608 ** See also: [sqlite3_column_count()] 4609 */ 4610 SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt); 4611 4612 /* 4613 ** CAPI3REF: Fundamental Datatypes 4614 ** KEYWORDS: SQLITE_TEXT 4615 ** 4616 ** ^(Every value in SQLite has one of five fundamental datatypes: 4617 ** 4618 ** <ul> 4619 ** <li> 64-bit signed integer 4620 ** <li> 64-bit IEEE floating point number 4621 ** <li> string 4622 ** <li> BLOB 4623 ** <li> NULL 4624 ** </ul>)^ 4625 ** 4626 ** These constants are codes for each of those types. 4627 ** 4628 ** Note that the SQLITE_TEXT constant was also used in SQLite version 2 4629 ** for a completely different meaning. Software that links against both 4630 ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not 4631 ** SQLITE_TEXT. 4632 */ 4633 #define SQLITE_INTEGER 1 4634 #define SQLITE_FLOAT 2 4635 #define SQLITE_BLOB 4 4636 #define SQLITE_NULL 5 4637 #ifdef SQLITE_TEXT 4638 # undef SQLITE_TEXT 4639 #else 4640 # define SQLITE_TEXT 3 4641 #endif 4642 #define SQLITE3_TEXT 3 4643 4644 /* 4645 ** CAPI3REF: Result Values From A Query 4646 ** KEYWORDS: {column access functions} 4647 ** METHOD: sqlite3_stmt 4648 ** 4649 ** <b>Summary:</b> 4650 ** <blockquote><table border=0 cellpadding=0 cellspacing=0> 4651 ** <tr><td><b>sqlite3_column_blob</b><td>→<td>BLOB result 4652 ** <tr><td><b>sqlite3_column_double</b><td>→<td>REAL result 4653 ** <tr><td><b>sqlite3_column_int</b><td>→<td>32-bit INTEGER result 4654 ** <tr><td><b>sqlite3_column_int64</b><td>→<td>64-bit INTEGER result 4655 ** <tr><td><b>sqlite3_column_text</b><td>→<td>UTF-8 TEXT result 4656 ** <tr><td><b>sqlite3_column_text16</b><td>→<td>UTF-16 TEXT result 4657 ** <tr><td><b>sqlite3_column_value</b><td>→<td>The result as an 4658 ** [sqlite3_value|unprotected sqlite3_value] object. 4659 ** <tr><td> <td> <td> 4660 ** <tr><td><b>sqlite3_column_bytes</b><td>→<td>Size of a BLOB 4661 ** or a UTF-8 TEXT result in bytes 4662 ** <tr><td><b>sqlite3_column_bytes16 </b> 4663 ** <td>→ <td>Size of UTF-16 4664 ** TEXT in bytes 4665 ** <tr><td><b>sqlite3_column_type</b><td>→<td>Default 4666 ** datatype of the result 4667 ** </table></blockquote> 4668 ** 4669 ** <b>Details:</b> 4670 ** 4671 ** ^These routines return information about a single column of the current 4672 ** result row of a query. ^In every case the first argument is a pointer 4673 ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] 4674 ** that was returned from [sqlite3_prepare_v2()] or one of its variants) 4675 ** and the second argument is the index of the column for which information 4676 ** should be returned. ^The leftmost column of the result set has the index 0. 4677 ** ^The number of columns in the result can be determined using 4678 ** [sqlite3_column_count()]. 4679 ** 4680 ** If the SQL statement does not currently point to a valid row, or if the 4681 ** column index is out of range, the result is undefined. 4682 ** These routines may only be called when the most recent call to 4683 ** [sqlite3_step()] has returned [SQLITE_ROW] and neither 4684 ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. 4685 ** If any of these routines are called after [sqlite3_reset()] or 4686 ** [sqlite3_finalize()] or after [sqlite3_step()] has returned 4687 ** something other than [SQLITE_ROW], the results are undefined. 4688 ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] 4689 ** are called from a different thread while any of these routines 4690 ** are pending, then the results are undefined. 4691 ** 4692 ** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16) 4693 ** each return the value of a result column in a specific data format. If 4694 ** the result column is not initially in the requested format (for example, 4695 ** if the query returns an integer but the sqlite3_column_text() interface 4696 ** is used to extract the value) then an automatic type conversion is performed. 4697 ** 4698 ** ^The sqlite3_column_type() routine returns the 4699 ** [SQLITE_INTEGER | datatype code] for the initial data type 4700 ** of the result column. ^The returned value is one of [SQLITE_INTEGER], 4701 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. 4702 ** The return value of sqlite3_column_type() can be used to decide which 4703 ** of the first six interface should be used to extract the column value. 4704 ** The value returned by sqlite3_column_type() is only meaningful if no 4705 ** automatic type conversions have occurred for the value in question. 4706 ** After a type conversion, the result of calling sqlite3_column_type() 4707 ** is undefined, though harmless. Future 4708 ** versions of SQLite may change the behavior of sqlite3_column_type() 4709 ** following a type conversion. 4710 ** 4711 ** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes() 4712 ** or sqlite3_column_bytes16() interfaces can be used to determine the size 4713 ** of that BLOB or string. 4714 ** 4715 ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() 4716 ** routine returns the number of bytes in that BLOB or string. 4717 ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts 4718 ** the string to UTF-8 and then returns the number of bytes. 4719 ** ^If the result is a numeric value then sqlite3_column_bytes() uses 4720 ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns 4721 ** the number of bytes in that string. 4722 ** ^If the result is NULL, then sqlite3_column_bytes() returns zero. 4723 ** 4724 ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() 4725 ** routine returns the number of bytes in that BLOB or string. 4726 ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts 4727 ** the string to UTF-16 and then returns the number of bytes. 4728 ** ^If the result is a numeric value then sqlite3_column_bytes16() uses 4729 ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns 4730 ** the number of bytes in that string. 4731 ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. 4732 ** 4733 ** ^The values returned by [sqlite3_column_bytes()] and 4734 ** [sqlite3_column_bytes16()] do not include the zero terminators at the end 4735 ** of the string. ^For clarity: the values returned by 4736 ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of 4737 ** bytes in the string, not the number of characters. 4738 ** 4739 ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), 4740 ** even empty strings, are always zero-terminated. ^The return 4741 ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. 4742 ** 4743 ** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an 4744 ** [unprotected sqlite3_value] object. In a multithreaded environment, 4745 ** an unprotected sqlite3_value object may only be used safely with 4746 ** [sqlite3_bind_value()] and [sqlite3_result_value()]. 4747 ** If the [unprotected sqlite3_value] object returned by 4748 ** [sqlite3_column_value()] is used in any other way, including calls 4749 ** to routines like [sqlite3_value_int()], [sqlite3_value_text()], 4750 ** or [sqlite3_value_bytes()], the behavior is not threadsafe. 4751 ** Hence, the sqlite3_column_value() interface 4752 ** is normally only useful within the implementation of 4753 ** [application-defined SQL functions] or [virtual tables], not within 4754 ** top-level application code. 4755 ** 4756 ** The these routines may attempt to convert the datatype of the result. 4757 ** ^For example, if the internal representation is FLOAT and a text result 4758 ** is requested, [sqlite3_snprintf()] is used internally to perform the 4759 ** conversion automatically. ^(The following table details the conversions 4760 ** that are applied: 4761 ** 4762 ** <blockquote> 4763 ** <table border="1"> 4764 ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion 4765 ** 4766 ** <tr><td> NULL <td> INTEGER <td> Result is 0 4767 ** <tr><td> NULL <td> FLOAT <td> Result is 0.0 4768 ** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer 4769 ** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer 4770 ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float 4771 ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer 4772 ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT 4773 ** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER 4774 ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float 4775 ** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB 4776 ** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER 4777 ** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL 4778 ** <tr><td> TEXT <td> BLOB <td> No change 4779 ** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER 4780 ** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL 4781 ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed 4782 ** </table> 4783 ** </blockquote>)^ 4784 ** 4785 ** Note that when type conversions occur, pointers returned by prior 4786 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or 4787 ** sqlite3_column_text16() may be invalidated. 4788 ** Type conversions and pointer invalidations might occur 4789 ** in the following cases: 4790 ** 4791 ** <ul> 4792 ** <li> The initial content is a BLOB and sqlite3_column_text() or 4793 ** sqlite3_column_text16() is called. A zero-terminator might 4794 ** need to be added to the string.</li> 4795 ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or 4796 ** sqlite3_column_text16() is called. The content must be converted 4797 ** to UTF-16.</li> 4798 ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or 4799 ** sqlite3_column_text() is called. The content must be converted 4800 ** to UTF-8.</li> 4801 ** </ul> 4802 ** 4803 ** ^Conversions between UTF-16be and UTF-16le are always done in place and do 4804 ** not invalidate a prior pointer, though of course the content of the buffer 4805 ** that the prior pointer references will have been modified. Other kinds 4806 ** of conversion are done in place when it is possible, but sometimes they 4807 ** are not possible and in those cases prior pointers are invalidated. 4808 ** 4809 ** The safest policy is to invoke these routines 4810 ** in one of the following ways: 4811 ** 4812 ** <ul> 4813 ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> 4814 ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> 4815 ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> 4816 ** </ul> 4817 ** 4818 ** In other words, you should call sqlite3_column_text(), 4819 ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result 4820 ** into the desired format, then invoke sqlite3_column_bytes() or 4821 ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls 4822 ** to sqlite3_column_text() or sqlite3_column_blob() with calls to 4823 ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() 4824 ** with calls to sqlite3_column_bytes(). 4825 ** 4826 ** ^The pointers returned are valid until a type conversion occurs as 4827 ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or 4828 ** [sqlite3_finalize()] is called. ^The memory space used to hold strings 4829 ** and BLOBs is freed automatically. Do not pass the pointers returned 4830 ** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into 4831 ** [sqlite3_free()]. 4832 ** 4833 ** As long as the input parameters are correct, these routines will only 4834 ** fail if an out-of-memory error occurs during a format conversion. 4835 ** Only the following subset of interfaces are subject to out-of-memory 4836 ** errors: 4837 ** 4838 ** <ul> 4839 ** <li> sqlite3_column_blob() 4840 ** <li> sqlite3_column_text() 4841 ** <li> sqlite3_column_text16() 4842 ** <li> sqlite3_column_bytes() 4843 ** <li> sqlite3_column_bytes16() 4844 ** </ul> 4845 ** 4846 ** If an out-of-memory error occurs, then the return value from these 4847 ** routines is the same as if the column had contained an SQL NULL value. 4848 ** Valid SQL NULL returns can be distinguished from out-of-memory errors 4849 ** by invoking the [sqlite3_errcode()] immediately after the suspect 4850 ** return value is obtained and before any 4851 ** other SQLite interface is called on the same [database connection]. 4852 */ 4853 SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); 4854 SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol); 4855 SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol); 4856 SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); 4857 SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); 4858 SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); 4859 SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); 4860 SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol); 4861 SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); 4862 SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol); 4863 4864 /* 4865 ** CAPI3REF: Destroy A Prepared Statement Object 4866 ** DESTRUCTOR: sqlite3_stmt 4867 ** 4868 ** ^The sqlite3_finalize() function is called to delete a [prepared statement]. 4869 ** ^If the most recent evaluation of the statement encountered no errors 4870 ** or if the statement is never been evaluated, then sqlite3_finalize() returns 4871 ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then 4872 ** sqlite3_finalize(S) returns the appropriate [error code] or 4873 ** [extended error code]. 4874 ** 4875 ** ^The sqlite3_finalize(S) routine can be called at any point during 4876 ** the life cycle of [prepared statement] S: 4877 ** before statement S is ever evaluated, after 4878 ** one or more calls to [sqlite3_reset()], or after any call 4879 ** to [sqlite3_step()] regardless of whether or not the statement has 4880 ** completed execution. 4881 ** 4882 ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. 4883 ** 4884 ** The application must finalize every [prepared statement] in order to avoid 4885 ** resource leaks. It is a grievous error for the application to try to use 4886 ** a prepared statement after it has been finalized. Any use of a prepared 4887 ** statement after it has been finalized can result in undefined and 4888 ** undesirable behavior such as segfaults and heap corruption. 4889 */ 4890 SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt); 4891 4892 /* 4893 ** CAPI3REF: Reset A Prepared Statement Object 4894 ** METHOD: sqlite3_stmt 4895 ** 4896 ** The sqlite3_reset() function is called to reset a [prepared statement] 4897 ** object back to its initial state, ready to be re-executed. 4898 ** ^Any SQL statement variables that had values bound to them using 4899 ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. 4900 ** Use [sqlite3_clear_bindings()] to reset the bindings. 4901 ** 4902 ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S 4903 ** back to the beginning of its program. 4904 ** 4905 ** ^If the most recent call to [sqlite3_step(S)] for the 4906 ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE], 4907 ** or if [sqlite3_step(S)] has never before been called on S, 4908 ** then [sqlite3_reset(S)] returns [SQLITE_OK]. 4909 ** 4910 ** ^If the most recent call to [sqlite3_step(S)] for the 4911 ** [prepared statement] S indicated an error, then 4912 ** [sqlite3_reset(S)] returns an appropriate [error code]. 4913 ** 4914 ** ^The [sqlite3_reset(S)] interface does not change the values 4915 ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. 4916 */ 4917 SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt); 4918 4919 /* 4920 ** CAPI3REF: Create Or Redefine SQL Functions 4921 ** KEYWORDS: {function creation routines} 4922 ** METHOD: sqlite3 4923 ** 4924 ** ^These functions (collectively known as "function creation routines") 4925 ** are used to add SQL functions or aggregates or to redefine the behavior 4926 ** of existing SQL functions or aggregates. The only differences between 4927 ** the three "sqlite3_create_function*" routines are the text encoding 4928 ** expected for the second parameter (the name of the function being 4929 ** created) and the presence or absence of a destructor callback for 4930 ** the application data pointer. Function sqlite3_create_window_function() 4931 ** is similar, but allows the user to supply the extra callback functions 4932 ** needed by [aggregate window functions]. 4933 ** 4934 ** ^The first parameter is the [database connection] to which the SQL 4935 ** function is to be added. ^If an application uses more than one database 4936 ** connection then application-defined SQL functions must be added 4937 ** to each database connection separately. 4938 ** 4939 ** ^The second parameter is the name of the SQL function to be created or 4940 ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 4941 ** representation, exclusive of the zero-terminator. ^Note that the name 4942 ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. 4943 ** ^Any attempt to create a function with a longer name 4944 ** will result in [SQLITE_MISUSE] being returned. 4945 ** 4946 ** ^The third parameter (nArg) 4947 ** is the number of arguments that the SQL function or 4948 ** aggregate takes. ^If this parameter is -1, then the SQL function or 4949 ** aggregate may take any number of arguments between 0 and the limit 4950 ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third 4951 ** parameter is less than -1 or greater than 127 then the behavior is 4952 ** undefined. 4953 ** 4954 ** ^The fourth parameter, eTextRep, specifies what 4955 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for 4956 ** its parameters. The application should set this parameter to 4957 ** [SQLITE_UTF16LE] if the function implementation invokes 4958 ** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the 4959 ** implementation invokes [sqlite3_value_text16be()] on an input, or 4960 ** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8] 4961 ** otherwise. ^The same SQL function may be registered multiple times using 4962 ** different preferred text encodings, with different implementations for 4963 ** each encoding. 4964 ** ^When multiple implementations of the same function are available, SQLite 4965 ** will pick the one that involves the least amount of data conversion. 4966 ** 4967 ** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC] 4968 ** to signal that the function will always return the same result given 4969 ** the same inputs within a single SQL statement. Most SQL functions are 4970 ** deterministic. The built-in [random()] SQL function is an example of a 4971 ** function that is not deterministic. The SQLite query planner is able to 4972 ** perform additional optimizations on deterministic functions, so use 4973 ** of the [SQLITE_DETERMINISTIC] flag is recommended where possible. 4974 ** 4975 ** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY] 4976 ** flag, which if present prevents the function from being invoked from 4977 ** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions, 4978 ** index expressions, or the WHERE clause of partial indexes. 4979 ** 4980 ** <span style="background-color:#ffff90;"> 4981 ** For best security, the [SQLITE_DIRECTONLY] flag is recommended for 4982 ** all application-defined SQL functions that do not need to be 4983 ** used inside of triggers, view, CHECK constraints, or other elements of 4984 ** the database schema. This flags is especially recommended for SQL 4985 ** functions that have side effects or reveal internal application state. 4986 ** Without this flag, an attacker might be able to modify the schema of 4987 ** a database file to include invocations of the function with parameters 4988 ** chosen by the attacker, which the application will then execute when 4989 ** the database file is opened and read. 4990 ** </span> 4991 ** 4992 ** ^(The fifth parameter is an arbitrary pointer. The implementation of the 4993 ** function can gain access to this pointer using [sqlite3_user_data()].)^ 4994 ** 4995 ** ^The sixth, seventh and eighth parameters passed to the three 4996 ** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are 4997 ** pointers to C-language functions that implement the SQL function or 4998 ** aggregate. ^A scalar SQL function requires an implementation of the xFunc 4999 ** callback only; NULL pointers must be passed as the xStep and xFinal 5000 ** parameters. ^An aggregate SQL function requires an implementation of xStep 5001 ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing 5002 ** SQL function or aggregate, pass NULL pointers for all three function 5003 ** callbacks. 5004 ** 5005 ** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue 5006 ** and xInverse) passed to sqlite3_create_window_function are pointers to 5007 ** C-language callbacks that implement the new function. xStep and xFinal 5008 ** must both be non-NULL. xValue and xInverse may either both be NULL, in 5009 ** which case a regular aggregate function is created, or must both be 5010 ** non-NULL, in which case the new function may be used as either an aggregate 5011 ** or aggregate window function. More details regarding the implementation 5012 ** of aggregate window functions are 5013 ** [user-defined window functions|available here]. 5014 ** 5015 ** ^(If the final parameter to sqlite3_create_function_v2() or 5016 ** sqlite3_create_window_function() is not NULL, then it is destructor for 5017 ** the application data pointer. The destructor is invoked when the function 5018 ** is deleted, either by being overloaded or when the database connection 5019 ** closes.)^ ^The destructor is also invoked if the call to 5020 ** sqlite3_create_function_v2() fails. ^When the destructor callback is 5021 ** invoked, it is passed a single argument which is a copy of the application 5022 ** data pointer which was the fifth parameter to sqlite3_create_function_v2(). 5023 ** 5024 ** ^It is permitted to register multiple implementations of the same 5025 ** functions with the same name but with either differing numbers of 5026 ** arguments or differing preferred text encodings. ^SQLite will use 5027 ** the implementation that most closely matches the way in which the 5028 ** SQL function is used. ^A function implementation with a non-negative 5029 ** nArg parameter is a better match than a function implementation with 5030 ** a negative nArg. ^A function where the preferred text encoding 5031 ** matches the database encoding is a better 5032 ** match than a function where the encoding is different. 5033 ** ^A function where the encoding difference is between UTF16le and UTF16be 5034 ** is a closer match than a function where the encoding difference is 5035 ** between UTF8 and UTF16. 5036 ** 5037 ** ^Built-in functions may be overloaded by new application-defined functions. 5038 ** 5039 ** ^An application-defined function is permitted to call other 5040 ** SQLite interfaces. However, such calls must not 5041 ** close the database connection nor finalize or reset the prepared 5042 ** statement in which the function is running. 5043 */ 5044 SQLITE_API int sqlite3_create_function( 5045 sqlite3 *db, 5046 const char *zFunctionName, 5047 int nArg, 5048 int eTextRep, 5049 void *pApp, 5050 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5051 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5052 void (*xFinal)(sqlite3_context*) 5053 ); 5054 SQLITE_API int sqlite3_create_function16( 5055 sqlite3 *db, 5056 const void *zFunctionName, 5057 int nArg, 5058 int eTextRep, 5059 void *pApp, 5060 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5061 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5062 void (*xFinal)(sqlite3_context*) 5063 ); 5064 SQLITE_API int sqlite3_create_function_v2( 5065 sqlite3 *db, 5066 const char *zFunctionName, 5067 int nArg, 5068 int eTextRep, 5069 void *pApp, 5070 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5071 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5072 void (*xFinal)(sqlite3_context*), 5073 void(*xDestroy)(void*) 5074 ); 5075 SQLITE_API int sqlite3_create_window_function( 5076 sqlite3 *db, 5077 const char *zFunctionName, 5078 int nArg, 5079 int eTextRep, 5080 void *pApp, 5081 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5082 void (*xFinal)(sqlite3_context*), 5083 void (*xValue)(sqlite3_context*), 5084 void (*xInverse)(sqlite3_context*,int,sqlite3_value**), 5085 void(*xDestroy)(void*) 5086 ); 5087 5088 /* 5089 ** CAPI3REF: Text Encodings 5090 ** 5091 ** These constant define integer codes that represent the various 5092 ** text encodings supported by SQLite. 5093 */ 5094 #define SQLITE_UTF8 1 /* IMP: R-37514-35566 */ 5095 #define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */ 5096 #define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */ 5097 #define SQLITE_UTF16 4 /* Use native byte order */ 5098 #define SQLITE_ANY 5 /* Deprecated */ 5099 #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ 5100 5101 /* 5102 ** CAPI3REF: Function Flags 5103 ** 5104 ** These constants may be ORed together with the 5105 ** [SQLITE_UTF8 | preferred text encoding] as the fourth argument 5106 ** to [sqlite3_create_function()], [sqlite3_create_function16()], or 5107 ** [sqlite3_create_function_v2()]. 5108 ** 5109 ** <dl> 5110 ** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd> 5111 ** The SQLITE_DETERMINISTIC flag means that the new function always gives 5112 ** the same output when the input parameters are the same. 5113 ** The [abs|abs() function] is deterministic, for example, but 5114 ** [randomblob|randomblob()] is not. Functions must 5115 ** be deterministic in order to be used in certain contexts such as 5116 ** with the WHERE clause of [partial indexes] or in [generated columns]. 5117 ** SQLite might also optimize deterministic functions by factoring them 5118 ** out of inner loops. 5119 ** </dd> 5120 ** 5121 ** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd> 5122 ** The SQLITE_DIRECTONLY flag means that the function may only be invoked 5123 ** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in 5124 ** schema structures such as [CHECK constraints], [DEFAULT clauses], 5125 ** [expression indexes], [partial indexes], or [generated columns]. 5126 ** The SQLITE_DIRECTONLY flags is a security feature which is recommended 5127 ** for all [application-defined SQL functions], and especially for functions 5128 ** that have side-effects or that could potentially leak sensitive 5129 ** information. 5130 ** </dd> 5131 ** 5132 ** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd> 5133 ** The SQLITE_INNOCUOUS flag means that the function is unlikely 5134 ** to cause problems even if misused. An innocuous function should have 5135 ** no side effects and should not depend on any values other than its 5136 ** input parameters. The [abs|abs() function] is an example of an 5137 ** innocuous function. 5138 ** The [load_extension() SQL function] is not innocuous because of its 5139 ** side effects. 5140 ** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not 5141 ** exactly the same. The [random|random() function] is an example of a 5142 ** function that is innocuous but not deterministic. 5143 ** <p>Some heightened security settings 5144 ** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF]) 5145 ** disable the use of SQL functions inside views and triggers and in 5146 ** schema structures such as [CHECK constraints], [DEFAULT clauses], 5147 ** [expression indexes], [partial indexes], and [generated columns] unless 5148 ** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions 5149 ** are innocuous. Developers are advised to avoid using the 5150 ** SQLITE_INNOCUOUS flag for application-defined functions unless the 5151 ** function has been carefully audited and found to be free of potentially 5152 ** security-adverse side-effects and information-leaks. 5153 ** </dd> 5154 ** 5155 ** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd> 5156 ** The SQLITE_SUBTYPE flag indicates to SQLite that a function may call 5157 ** [sqlite3_value_subtype()] to inspect the sub-types of its arguments. 5158 ** Specifying this flag makes no difference for scalar or aggregate user 5159 ** functions. However, if it is not specified for a user-defined window 5160 ** function, then any sub-types belonging to arguments passed to the window 5161 ** function may be discarded before the window function is called (i.e. 5162 ** sqlite3_value_subtype() will always return 0). 5163 ** </dd> 5164 ** </dl> 5165 */ 5166 #define SQLITE_DETERMINISTIC 0x000000800 5167 #define SQLITE_DIRECTONLY 0x000080000 5168 #define SQLITE_SUBTYPE 0x000100000 5169 #define SQLITE_INNOCUOUS 0x000200000 5170 5171 /* 5172 ** CAPI3REF: Deprecated Functions 5173 ** DEPRECATED 5174 ** 5175 ** These functions are [deprecated]. In order to maintain 5176 ** backwards compatibility with older code, these functions continue 5177 ** to be supported. However, new applications should avoid 5178 ** the use of these functions. To encourage programmers to avoid 5179 ** these functions, we will not explain what they do. 5180 */ 5181 #ifndef SQLITE_OMIT_DEPRECATED 5182 SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); 5183 SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); 5184 SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); 5185 SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void); 5186 SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); 5187 SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int), 5188 void*,sqlite3_int64); 5189 #endif 5190 5191 /* 5192 ** CAPI3REF: Obtaining SQL Values 5193 ** METHOD: sqlite3_value 5194 ** 5195 ** <b>Summary:</b> 5196 ** <blockquote><table border=0 cellpadding=0 cellspacing=0> 5197 ** <tr><td><b>sqlite3_value_blob</b><td>→<td>BLOB value 5198 ** <tr><td><b>sqlite3_value_double</b><td>→<td>REAL value 5199 ** <tr><td><b>sqlite3_value_int</b><td>→<td>32-bit INTEGER value 5200 ** <tr><td><b>sqlite3_value_int64</b><td>→<td>64-bit INTEGER value 5201 ** <tr><td><b>sqlite3_value_pointer</b><td>→<td>Pointer value 5202 ** <tr><td><b>sqlite3_value_text</b><td>→<td>UTF-8 TEXT value 5203 ** <tr><td><b>sqlite3_value_text16</b><td>→<td>UTF-16 TEXT value in 5204 ** the native byteorder 5205 ** <tr><td><b>sqlite3_value_text16be</b><td>→<td>UTF-16be TEXT value 5206 ** <tr><td><b>sqlite3_value_text16le</b><td>→<td>UTF-16le TEXT value 5207 ** <tr><td> <td> <td> 5208 ** <tr><td><b>sqlite3_value_bytes</b><td>→<td>Size of a BLOB 5209 ** or a UTF-8 TEXT in bytes 5210 ** <tr><td><b>sqlite3_value_bytes16 </b> 5211 ** <td>→ <td>Size of UTF-16 5212 ** TEXT in bytes 5213 ** <tr><td><b>sqlite3_value_type</b><td>→<td>Default 5214 ** datatype of the value 5215 ** <tr><td><b>sqlite3_value_numeric_type </b> 5216 ** <td>→ <td>Best numeric datatype of the value 5217 ** <tr><td><b>sqlite3_value_nochange </b> 5218 ** <td>→ <td>True if the column is unchanged in an UPDATE 5219 ** against a virtual table. 5220 ** <tr><td><b>sqlite3_value_frombind </b> 5221 ** <td>→ <td>True if value originated from a [bound parameter] 5222 ** </table></blockquote> 5223 ** 5224 ** <b>Details:</b> 5225 ** 5226 ** These routines extract type, size, and content information from 5227 ** [protected sqlite3_value] objects. Protected sqlite3_value objects 5228 ** are used to pass parameter information into the functions that 5229 ** implement [application-defined SQL functions] and [virtual tables]. 5230 ** 5231 ** These routines work only with [protected sqlite3_value] objects. 5232 ** Any attempt to use these routines on an [unprotected sqlite3_value] 5233 ** is not threadsafe. 5234 ** 5235 ** ^These routines work just like the corresponding [column access functions] 5236 ** except that these routines take a single [protected sqlite3_value] object 5237 ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. 5238 ** 5239 ** ^The sqlite3_value_text16() interface extracts a UTF-16 string 5240 ** in the native byte-order of the host machine. ^The 5241 ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces 5242 ** extract UTF-16 strings as big-endian and little-endian respectively. 5243 ** 5244 ** ^If [sqlite3_value] object V was initialized 5245 ** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)] 5246 ** and if X and Y are strings that compare equal according to strcmp(X,Y), 5247 ** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise, 5248 ** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer() 5249 ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 5250 ** 5251 ** ^(The sqlite3_value_type(V) interface returns the 5252 ** [SQLITE_INTEGER | datatype code] for the initial datatype of the 5253 ** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER], 5254 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^ 5255 ** Other interfaces might change the datatype for an sqlite3_value object. 5256 ** For example, if the datatype is initially SQLITE_INTEGER and 5257 ** sqlite3_value_text(V) is called to extract a text value for that 5258 ** integer, then subsequent calls to sqlite3_value_type(V) might return 5259 ** SQLITE_TEXT. Whether or not a persistent internal datatype conversion 5260 ** occurs is undefined and may change from one release of SQLite to the next. 5261 ** 5262 ** ^(The sqlite3_value_numeric_type() interface attempts to apply 5263 ** numeric affinity to the value. This means that an attempt is 5264 ** made to convert the value to an integer or floating point. If 5265 ** such a conversion is possible without loss of information (in other 5266 ** words, if the value is a string that looks like a number) 5267 ** then the conversion is performed. Otherwise no conversion occurs. 5268 ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ 5269 ** 5270 ** ^Within the [xUpdate] method of a [virtual table], the 5271 ** sqlite3_value_nochange(X) interface returns true if and only if 5272 ** the column corresponding to X is unchanged by the UPDATE operation 5273 ** that the xUpdate method call was invoked to implement and if 5274 ** and the prior [xColumn] method call that was invoked to extracted 5275 ** the value for that column returned without setting a result (probably 5276 ** because it queried [sqlite3_vtab_nochange()] and found that the column 5277 ** was unchanging). ^Within an [xUpdate] method, any value for which 5278 ** sqlite3_value_nochange(X) is true will in all other respects appear 5279 ** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other 5280 ** than within an [xUpdate] method call for an UPDATE statement, then 5281 ** the return value is arbitrary and meaningless. 5282 ** 5283 ** ^The sqlite3_value_frombind(X) interface returns non-zero if the 5284 ** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()] 5285 ** interfaces. ^If X comes from an SQL literal value, or a table column, 5286 ** or an expression, then sqlite3_value_frombind(X) returns zero. 5287 ** 5288 ** Please pay particular attention to the fact that the pointer returned 5289 ** from [sqlite3_value_blob()], [sqlite3_value_text()], or 5290 ** [sqlite3_value_text16()] can be invalidated by a subsequent call to 5291 ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], 5292 ** or [sqlite3_value_text16()]. 5293 ** 5294 ** These routines must be called from the same thread as 5295 ** the SQL function that supplied the [sqlite3_value*] parameters. 5296 ** 5297 ** As long as the input parameter is correct, these routines can only 5298 ** fail if an out-of-memory error occurs during a format conversion. 5299 ** Only the following subset of interfaces are subject to out-of-memory 5300 ** errors: 5301 ** 5302 ** <ul> 5303 ** <li> sqlite3_value_blob() 5304 ** <li> sqlite3_value_text() 5305 ** <li> sqlite3_value_text16() 5306 ** <li> sqlite3_value_text16le() 5307 ** <li> sqlite3_value_text16be() 5308 ** <li> sqlite3_value_bytes() 5309 ** <li> sqlite3_value_bytes16() 5310 ** </ul> 5311 ** 5312 ** If an out-of-memory error occurs, then the return value from these 5313 ** routines is the same as if the column had contained an SQL NULL value. 5314 ** Valid SQL NULL returns can be distinguished from out-of-memory errors 5315 ** by invoking the [sqlite3_errcode()] immediately after the suspect 5316 ** return value is obtained and before any 5317 ** other SQLite interface is called on the same [database connection]. 5318 */ 5319 SQLITE_API const void *sqlite3_value_blob(sqlite3_value*); 5320 SQLITE_API double sqlite3_value_double(sqlite3_value*); 5321 SQLITE_API int sqlite3_value_int(sqlite3_value*); 5322 SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*); 5323 SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*); 5324 SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*); 5325 SQLITE_API const void *sqlite3_value_text16(sqlite3_value*); 5326 SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*); 5327 SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*); 5328 SQLITE_API int sqlite3_value_bytes(sqlite3_value*); 5329 SQLITE_API int sqlite3_value_bytes16(sqlite3_value*); 5330 SQLITE_API int sqlite3_value_type(sqlite3_value*); 5331 SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*); 5332 SQLITE_API int sqlite3_value_nochange(sqlite3_value*); 5333 SQLITE_API int sqlite3_value_frombind(sqlite3_value*); 5334 5335 /* 5336 ** CAPI3REF: Finding The Subtype Of SQL Values 5337 ** METHOD: sqlite3_value 5338 ** 5339 ** The sqlite3_value_subtype(V) function returns the subtype for 5340 ** an [application-defined SQL function] argument V. The subtype 5341 ** information can be used to pass a limited amount of context from 5342 ** one SQL function to another. Use the [sqlite3_result_subtype()] 5343 ** routine to set the subtype for the return value of an SQL function. 5344 */ 5345 SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*); 5346 5347 /* 5348 ** CAPI3REF: Copy And Free SQL Values 5349 ** METHOD: sqlite3_value 5350 ** 5351 ** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value] 5352 ** object D and returns a pointer to that copy. ^The [sqlite3_value] returned 5353 ** is a [protected sqlite3_value] object even if the input is not. 5354 ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a 5355 ** memory allocation fails. 5356 ** 5357 ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object 5358 ** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer 5359 ** then sqlite3_value_free(V) is a harmless no-op. 5360 */ 5361 SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*); 5362 SQLITE_API void sqlite3_value_free(sqlite3_value*); 5363 5364 /* 5365 ** CAPI3REF: Obtain Aggregate Function Context 5366 ** METHOD: sqlite3_context 5367 ** 5368 ** Implementations of aggregate SQL functions use this 5369 ** routine to allocate memory for storing their state. 5370 ** 5371 ** ^The first time the sqlite3_aggregate_context(C,N) routine is called 5372 ** for a particular aggregate function, SQLite allocates 5373 ** N bytes of memory, zeroes out that memory, and returns a pointer 5374 ** to the new memory. ^On second and subsequent calls to 5375 ** sqlite3_aggregate_context() for the same aggregate function instance, 5376 ** the same buffer is returned. Sqlite3_aggregate_context() is normally 5377 ** called once for each invocation of the xStep callback and then one 5378 ** last time when the xFinal callback is invoked. ^(When no rows match 5379 ** an aggregate query, the xStep() callback of the aggregate function 5380 ** implementation is never called and xFinal() is called exactly once. 5381 ** In those cases, sqlite3_aggregate_context() might be called for the 5382 ** first time from within xFinal().)^ 5383 ** 5384 ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 5385 ** when first called if N is less than or equal to zero or if a memory 5386 ** allocate error occurs. 5387 ** 5388 ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is 5389 ** determined by the N parameter on first successful call. Changing the 5390 ** value of N in any subsequents call to sqlite3_aggregate_context() within 5391 ** the same aggregate function instance will not resize the memory 5392 ** allocation.)^ Within the xFinal callback, it is customary to set 5393 ** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 5394 ** pointless memory allocations occur. 5395 ** 5396 ** ^SQLite automatically frees the memory allocated by 5397 ** sqlite3_aggregate_context() when the aggregate query concludes. 5398 ** 5399 ** The first parameter must be a copy of the 5400 ** [sqlite3_context | SQL function context] that is the first parameter 5401 ** to the xStep or xFinal callback routine that implements the aggregate 5402 ** function. 5403 ** 5404 ** This routine must be called from the same thread in which 5405 ** the aggregate SQL function is running. 5406 */ 5407 SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); 5408 5409 /* 5410 ** CAPI3REF: User Data For Functions 5411 ** METHOD: sqlite3_context 5412 ** 5413 ** ^The sqlite3_user_data() interface returns a copy of 5414 ** the pointer that was the pUserData parameter (the 5th parameter) 5415 ** of the [sqlite3_create_function()] 5416 ** and [sqlite3_create_function16()] routines that originally 5417 ** registered the application defined function. 5418 ** 5419 ** This routine must be called from the same thread in which 5420 ** the application-defined function is running. 5421 */ 5422 SQLITE_API void *sqlite3_user_data(sqlite3_context*); 5423 5424 /* 5425 ** CAPI3REF: Database Connection For Functions 5426 ** METHOD: sqlite3_context 5427 ** 5428 ** ^The sqlite3_context_db_handle() interface returns a copy of 5429 ** the pointer to the [database connection] (the 1st parameter) 5430 ** of the [sqlite3_create_function()] 5431 ** and [sqlite3_create_function16()] routines that originally 5432 ** registered the application defined function. 5433 */ 5434 SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*); 5435 5436 /* 5437 ** CAPI3REF: Function Auxiliary Data 5438 ** METHOD: sqlite3_context 5439 ** 5440 ** These functions may be used by (non-aggregate) SQL functions to 5441 ** associate metadata with argument values. If the same value is passed to 5442 ** multiple invocations of the same SQL function during query execution, under 5443 ** some circumstances the associated metadata may be preserved. An example 5444 ** of where this might be useful is in a regular-expression matching 5445 ** function. The compiled version of the regular expression can be stored as 5446 ** metadata associated with the pattern string. 5447 ** Then as long as the pattern string remains the same, 5448 ** the compiled regular expression can be reused on multiple 5449 ** invocations of the same function. 5450 ** 5451 ** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata 5452 ** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument 5453 ** value to the application-defined function. ^N is zero for the left-most 5454 ** function argument. ^If there is no metadata 5455 ** associated with the function argument, the sqlite3_get_auxdata(C,N) interface 5456 ** returns a NULL pointer. 5457 ** 5458 ** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th 5459 ** argument of the application-defined function. ^Subsequent 5460 ** calls to sqlite3_get_auxdata(C,N) return P from the most recent 5461 ** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or 5462 ** NULL if the metadata has been discarded. 5463 ** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL, 5464 ** SQLite will invoke the destructor function X with parameter P exactly 5465 ** once, when the metadata is discarded. 5466 ** SQLite is free to discard the metadata at any time, including: <ul> 5467 ** <li> ^(when the corresponding function parameter changes)^, or 5468 ** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the 5469 ** SQL statement)^, or 5470 ** <li> ^(when sqlite3_set_auxdata() is invoked again on the same 5471 ** parameter)^, or 5472 ** <li> ^(during the original sqlite3_set_auxdata() call when a memory 5473 ** allocation error occurs.)^ </ul> 5474 ** 5475 ** Note the last bullet in particular. The destructor X in 5476 ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the 5477 ** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata() 5478 ** should be called near the end of the function implementation and the 5479 ** function implementation should not make any use of P after 5480 ** sqlite3_set_auxdata() has been called. 5481 ** 5482 ** ^(In practice, metadata is preserved between function calls for 5483 ** function parameters that are compile-time constants, including literal 5484 ** values and [parameters] and expressions composed from the same.)^ 5485 ** 5486 ** The value of the N parameter to these interfaces should be non-negative. 5487 ** Future enhancements may make use of negative N values to define new 5488 ** kinds of function caching behavior. 5489 ** 5490 ** These routines must be called from the same thread in which 5491 ** the SQL function is running. 5492 */ 5493 SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N); 5494 SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); 5495 5496 5497 /* 5498 ** CAPI3REF: Constants Defining Special Destructor Behavior 5499 ** 5500 ** These are special values for the destructor that is passed in as the 5501 ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor 5502 ** argument is SQLITE_STATIC, it means that the content pointer is constant 5503 ** and will never change. It does not need to be destroyed. ^The 5504 ** SQLITE_TRANSIENT value means that the content will likely change in 5505 ** the near future and that SQLite should make its own private copy of 5506 ** the content before returning. 5507 ** 5508 ** The typedef is necessary to work around problems in certain 5509 ** C++ compilers. 5510 */ 5511 typedef void (*sqlite3_destructor_type)(void*); 5512 #define SQLITE_STATIC ((sqlite3_destructor_type)0) 5513 #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) 5514 5515 /* 5516 ** CAPI3REF: Setting The Result Of An SQL Function 5517 ** METHOD: sqlite3_context 5518 ** 5519 ** These routines are used by the xFunc or xFinal callbacks that 5520 ** implement SQL functions and aggregates. See 5521 ** [sqlite3_create_function()] and [sqlite3_create_function16()] 5522 ** for additional information. 5523 ** 5524 ** These functions work very much like the [parameter binding] family of 5525 ** functions used to bind values to host parameters in prepared statements. 5526 ** Refer to the [SQL parameter] documentation for additional information. 5527 ** 5528 ** ^The sqlite3_result_blob() interface sets the result from 5529 ** an application-defined function to be the BLOB whose content is pointed 5530 ** to by the second parameter and which is N bytes long where N is the 5531 ** third parameter. 5532 ** 5533 ** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N) 5534 ** interfaces set the result of the application-defined function to be 5535 ** a BLOB containing all zero bytes and N bytes in size. 5536 ** 5537 ** ^The sqlite3_result_double() interface sets the result from 5538 ** an application-defined function to be a floating point value specified 5539 ** by its 2nd argument. 5540 ** 5541 ** ^The sqlite3_result_error() and sqlite3_result_error16() functions 5542 ** cause the implemented SQL function to throw an exception. 5543 ** ^SQLite uses the string pointed to by the 5544 ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() 5545 ** as the text of an error message. ^SQLite interprets the error 5546 ** message string from sqlite3_result_error() as UTF-8. ^SQLite 5547 ** interprets the string from sqlite3_result_error16() as UTF-16 in native 5548 ** byte order. ^If the third parameter to sqlite3_result_error() 5549 ** or sqlite3_result_error16() is negative then SQLite takes as the error 5550 ** message all text up through the first zero character. 5551 ** ^If the third parameter to sqlite3_result_error() or 5552 ** sqlite3_result_error16() is non-negative then SQLite takes that many 5553 ** bytes (not characters) from the 2nd parameter as the error message. 5554 ** ^The sqlite3_result_error() and sqlite3_result_error16() 5555 ** routines make a private copy of the error message text before 5556 ** they return. Hence, the calling function can deallocate or 5557 ** modify the text after they return without harm. 5558 ** ^The sqlite3_result_error_code() function changes the error code 5559 ** returned by SQLite as a result of an error in a function. ^By default, 5560 ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() 5561 ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. 5562 ** 5563 ** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an 5564 ** error indicating that a string or BLOB is too long to represent. 5565 ** 5566 ** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an 5567 ** error indicating that a memory allocation failed. 5568 ** 5569 ** ^The sqlite3_result_int() interface sets the return value 5570 ** of the application-defined function to be the 32-bit signed integer 5571 ** value given in the 2nd argument. 5572 ** ^The sqlite3_result_int64() interface sets the return value 5573 ** of the application-defined function to be the 64-bit signed integer 5574 ** value given in the 2nd argument. 5575 ** 5576 ** ^The sqlite3_result_null() interface sets the return value 5577 ** of the application-defined function to be NULL. 5578 ** 5579 ** ^The sqlite3_result_text(), sqlite3_result_text16(), 5580 ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces 5581 ** set the return value of the application-defined function to be 5582 ** a text string which is represented as UTF-8, UTF-16 native byte order, 5583 ** UTF-16 little endian, or UTF-16 big endian, respectively. 5584 ** ^The sqlite3_result_text64() interface sets the return value of an 5585 ** application-defined function to be a text string in an encoding 5586 ** specified by the fifth (and last) parameter, which must be one 5587 ** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]. 5588 ** ^SQLite takes the text result from the application from 5589 ** the 2nd parameter of the sqlite3_result_text* interfaces. 5590 ** ^If the 3rd parameter to the sqlite3_result_text* interfaces 5591 ** is negative, then SQLite takes result text from the 2nd parameter 5592 ** through the first zero character. 5593 ** ^If the 3rd parameter to the sqlite3_result_text* interfaces 5594 ** is non-negative, then as many bytes (not characters) of the text 5595 ** pointed to by the 2nd parameter are taken as the application-defined 5596 ** function result. If the 3rd parameter is non-negative, then it 5597 ** must be the byte offset into the string where the NUL terminator would 5598 ** appear if the string where NUL terminated. If any NUL characters occur 5599 ** in the string at a byte offset that is less than the value of the 3rd 5600 ** parameter, then the resulting string will contain embedded NULs and the 5601 ** result of expressions operating on strings with embedded NULs is undefined. 5602 ** ^If the 4th parameter to the sqlite3_result_text* interfaces 5603 ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that 5604 ** function as the destructor on the text or BLOB result when it has 5605 ** finished using that result. 5606 ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to 5607 ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite 5608 ** assumes that the text or BLOB result is in constant space and does not 5609 ** copy the content of the parameter nor call a destructor on the content 5610 ** when it has finished using that result. 5611 ** ^If the 4th parameter to the sqlite3_result_text* interfaces 5612 ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT 5613 ** then SQLite makes a copy of the result into space obtained 5614 ** from [sqlite3_malloc()] before it returns. 5615 ** 5616 ** ^The sqlite3_result_value() interface sets the result of 5617 ** the application-defined function to be a copy of the 5618 ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The 5619 ** sqlite3_result_value() interface makes a copy of the [sqlite3_value] 5620 ** so that the [sqlite3_value] specified in the parameter may change or 5621 ** be deallocated after sqlite3_result_value() returns without harm. 5622 ** ^A [protected sqlite3_value] object may always be used where an 5623 ** [unprotected sqlite3_value] object is required, so either 5624 ** kind of [sqlite3_value] object can be used with this interface. 5625 ** 5626 ** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an 5627 ** SQL NULL value, just like [sqlite3_result_null(C)], except that it 5628 ** also associates the host-language pointer P or type T with that 5629 ** NULL value such that the pointer can be retrieved within an 5630 ** [application-defined SQL function] using [sqlite3_value_pointer()]. 5631 ** ^If the D parameter is not NULL, then it is a pointer to a destructor 5632 ** for the P parameter. ^SQLite invokes D with P as its only argument 5633 ** when SQLite is finished with P. The T parameter should be a static 5634 ** string and preferably a string literal. The sqlite3_result_pointer() 5635 ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 5636 ** 5637 ** If these routines are called from within the different thread 5638 ** than the one containing the application-defined function that received 5639 ** the [sqlite3_context] pointer, the results are undefined. 5640 */ 5641 SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); 5642 SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*, 5643 sqlite3_uint64,void(*)(void*)); 5644 SQLITE_API void sqlite3_result_double(sqlite3_context*, double); 5645 SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int); 5646 SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int); 5647 SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*); 5648 SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*); 5649 SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int); 5650 SQLITE_API void sqlite3_result_int(sqlite3_context*, int); 5651 SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); 5652 SQLITE_API void sqlite3_result_null(sqlite3_context*); 5653 SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); 5654 SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64, 5655 void(*)(void*), unsigned char encoding); 5656 SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); 5657 SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); 5658 SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); 5659 SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*); 5660 SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*)); 5661 SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n); 5662 SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n); 5663 5664 5665 /* 5666 ** CAPI3REF: Setting The Subtype Of An SQL Function 5667 ** METHOD: sqlite3_context 5668 ** 5669 ** The sqlite3_result_subtype(C,T) function causes the subtype of 5670 ** the result from the [application-defined SQL function] with 5671 ** [sqlite3_context] C to be the value T. Only the lower 8 bits 5672 ** of the subtype T are preserved in current versions of SQLite; 5673 ** higher order bits are discarded. 5674 ** The number of subtype bytes preserved by SQLite might increase 5675 ** in future releases of SQLite. 5676 */ 5677 SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int); 5678 5679 /* 5680 ** CAPI3REF: Define New Collating Sequences 5681 ** METHOD: sqlite3 5682 ** 5683 ** ^These functions add, remove, or modify a [collation] associated 5684 ** with the [database connection] specified as the first argument. 5685 ** 5686 ** ^The name of the collation is a UTF-8 string 5687 ** for sqlite3_create_collation() and sqlite3_create_collation_v2() 5688 ** and a UTF-16 string in native byte order for sqlite3_create_collation16(). 5689 ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are 5690 ** considered to be the same name. 5691 ** 5692 ** ^(The third argument (eTextRep) must be one of the constants: 5693 ** <ul> 5694 ** <li> [SQLITE_UTF8], 5695 ** <li> [SQLITE_UTF16LE], 5696 ** <li> [SQLITE_UTF16BE], 5697 ** <li> [SQLITE_UTF16], or 5698 ** <li> [SQLITE_UTF16_ALIGNED]. 5699 ** </ul>)^ 5700 ** ^The eTextRep argument determines the encoding of strings passed 5701 ** to the collating function callback, xCompare. 5702 ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep 5703 ** force strings to be UTF16 with native byte order. 5704 ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin 5705 ** on an even byte address. 5706 ** 5707 ** ^The fourth argument, pArg, is an application data pointer that is passed 5708 ** through as the first argument to the collating function callback. 5709 ** 5710 ** ^The fifth argument, xCompare, is a pointer to the collating function. 5711 ** ^Multiple collating functions can be registered using the same name but 5712 ** with different eTextRep parameters and SQLite will use whichever 5713 ** function requires the least amount of data transformation. 5714 ** ^If the xCompare argument is NULL then the collating function is 5715 ** deleted. ^When all collating functions having the same name are deleted, 5716 ** that collation is no longer usable. 5717 ** 5718 ** ^The collating function callback is invoked with a copy of the pArg 5719 ** application data pointer and with two strings in the encoding specified 5720 ** by the eTextRep argument. The two integer parameters to the collating 5721 ** function callback are the length of the two strings, in bytes. The collating 5722 ** function must return an integer that is negative, zero, or positive 5723 ** if the first string is less than, equal to, or greater than the second, 5724 ** respectively. A collating function must always return the same answer 5725 ** given the same inputs. If two or more collating functions are registered 5726 ** to the same collation name (using different eTextRep values) then all 5727 ** must give an equivalent answer when invoked with equivalent strings. 5728 ** The collating function must obey the following properties for all 5729 ** strings A, B, and C: 5730 ** 5731 ** <ol> 5732 ** <li> If A==B then B==A. 5733 ** <li> If A==B and B==C then A==C. 5734 ** <li> If A<B THEN B>A. 5735 ** <li> If A<B and B<C then A<C. 5736 ** </ol> 5737 ** 5738 ** If a collating function fails any of the above constraints and that 5739 ** collating function is registered and used, then the behavior of SQLite 5740 ** is undefined. 5741 ** 5742 ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() 5743 ** with the addition that the xDestroy callback is invoked on pArg when 5744 ** the collating function is deleted. 5745 ** ^Collating functions are deleted when they are overridden by later 5746 ** calls to the collation creation functions or when the 5747 ** [database connection] is closed using [sqlite3_close()]. 5748 ** 5749 ** ^The xDestroy callback is <u>not</u> called if the 5750 ** sqlite3_create_collation_v2() function fails. Applications that invoke 5751 ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should 5752 ** check the return code and dispose of the application data pointer 5753 ** themselves rather than expecting SQLite to deal with it for them. 5754 ** This is different from every other SQLite interface. The inconsistency 5755 ** is unfortunate but cannot be changed without breaking backwards 5756 ** compatibility. 5757 ** 5758 ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. 5759 */ 5760 SQLITE_API int sqlite3_create_collation( 5761 sqlite3*, 5762 const char *zName, 5763 int eTextRep, 5764 void *pArg, 5765 int(*xCompare)(void*,int,const void*,int,const void*) 5766 ); 5767 SQLITE_API int sqlite3_create_collation_v2( 5768 sqlite3*, 5769 const char *zName, 5770 int eTextRep, 5771 void *pArg, 5772 int(*xCompare)(void*,int,const void*,int,const void*), 5773 void(*xDestroy)(void*) 5774 ); 5775 SQLITE_API int sqlite3_create_collation16( 5776 sqlite3*, 5777 const void *zName, 5778 int eTextRep, 5779 void *pArg, 5780 int(*xCompare)(void*,int,const void*,int,const void*) 5781 ); 5782 5783 /* 5784 ** CAPI3REF: Collation Needed Callbacks 5785 ** METHOD: sqlite3 5786 ** 5787 ** ^To avoid having to register all collation sequences before a database 5788 ** can be used, a single callback function may be registered with the 5789 ** [database connection] to be invoked whenever an undefined collation 5790 ** sequence is required. 5791 ** 5792 ** ^If the function is registered using the sqlite3_collation_needed() API, 5793 ** then it is passed the names of undefined collation sequences as strings 5794 ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, 5795 ** the names are passed as UTF-16 in machine native byte order. 5796 ** ^A call to either function replaces the existing collation-needed callback. 5797 ** 5798 ** ^(When the callback is invoked, the first argument passed is a copy 5799 ** of the second argument to sqlite3_collation_needed() or 5800 ** sqlite3_collation_needed16(). The second argument is the database 5801 ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], 5802 ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation 5803 ** sequence function required. The fourth parameter is the name of the 5804 ** required collation sequence.)^ 5805 ** 5806 ** The callback function should register the desired collation using 5807 ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or 5808 ** [sqlite3_create_collation_v2()]. 5809 */ 5810 SQLITE_API int sqlite3_collation_needed( 5811 sqlite3*, 5812 void*, 5813 void(*)(void*,sqlite3*,int eTextRep,const char*) 5814 ); 5815 SQLITE_API int sqlite3_collation_needed16( 5816 sqlite3*, 5817 void*, 5818 void(*)(void*,sqlite3*,int eTextRep,const void*) 5819 ); 5820 5821 #ifdef SQLITE_HAS_CODEC 5822 /* 5823 ** Specify the key for an encrypted database. This routine should be 5824 ** called right after sqlite3_open(). 5825 ** 5826 ** The code to implement this API is not available in the public release 5827 ** of SQLite. 5828 */ 5829 SQLITE_API int sqlite3_key( 5830 sqlite3 *db, /* Database to be rekeyed */ 5831 const void *pKey, int nKey /* The key */ 5832 ); 5833 SQLITE_API int sqlite3_key_v2( 5834 sqlite3 *db, /* Database to be rekeyed */ 5835 const char *zDbName, /* Name of the database */ 5836 const void *pKey, int nKey /* The key */ 5837 ); 5838 5839 /* 5840 ** Change the key on an open database. If the current database is not 5841 ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the 5842 ** database is decrypted. 5843 ** 5844 ** The code to implement this API is not available in the public release 5845 ** of SQLite. 5846 */ 5847 SQLITE_API int sqlite3_rekey( 5848 sqlite3 *db, /* Database to be rekeyed */ 5849 const void *pKey, int nKey /* The new key */ 5850 ); 5851 SQLITE_API int sqlite3_rekey_v2( 5852 sqlite3 *db, /* Database to be rekeyed */ 5853 const char *zDbName, /* Name of the database */ 5854 const void *pKey, int nKey /* The new key */ 5855 ); 5856 5857 /* 5858 ** Specify the activation key for a SEE database. Unless 5859 ** activated, none of the SEE routines will work. 5860 */ 5861 SQLITE_API void sqlite3_activate_see( 5862 const char *zPassPhrase /* Activation phrase */ 5863 ); 5864 #endif 5865 5866 #ifdef SQLITE_ENABLE_CEROD 5867 /* 5868 ** Specify the activation key for a CEROD database. Unless 5869 ** activated, none of the CEROD routines will work. 5870 */ 5871 SQLITE_API void sqlite3_activate_cerod( 5872 const char *zPassPhrase /* Activation phrase */ 5873 ); 5874 #endif 5875 5876 /* 5877 ** CAPI3REF: Suspend Execution For A Short Time 5878 ** 5879 ** The sqlite3_sleep() function causes the current thread to suspend execution 5880 ** for at least a number of milliseconds specified in its parameter. 5881 ** 5882 ** If the operating system does not support sleep requests with 5883 ** millisecond time resolution, then the time will be rounded up to 5884 ** the nearest second. The number of milliseconds of sleep actually 5885 ** requested from the operating system is returned. 5886 ** 5887 ** ^SQLite implements this interface by calling the xSleep() 5888 ** method of the default [sqlite3_vfs] object. If the xSleep() method 5889 ** of the default VFS is not implemented correctly, or not implemented at 5890 ** all, then the behavior of sqlite3_sleep() may deviate from the description 5891 ** in the previous paragraphs. 5892 */ 5893 SQLITE_API int sqlite3_sleep(int); 5894 5895 /* 5896 ** CAPI3REF: Name Of The Folder Holding Temporary Files 5897 ** 5898 ** ^(If this global variable is made to point to a string which is 5899 ** the name of a folder (a.k.a. directory), then all temporary files 5900 ** created by SQLite when using a built-in [sqlite3_vfs | VFS] 5901 ** will be placed in that directory.)^ ^If this variable 5902 ** is a NULL pointer, then SQLite performs a search for an appropriate 5903 ** temporary file directory. 5904 ** 5905 ** Applications are strongly discouraged from using this global variable. 5906 ** It is required to set a temporary folder on Windows Runtime (WinRT). 5907 ** But for all other platforms, it is highly recommended that applications 5908 ** neither read nor write this variable. This global variable is a relic 5909 ** that exists for backwards compatibility of legacy applications and should 5910 ** be avoided in new projects. 5911 ** 5912 ** It is not safe to read or modify this variable in more than one 5913 ** thread at a time. It is not safe to read or modify this variable 5914 ** if a [database connection] is being used at the same time in a separate 5915 ** thread. 5916 ** It is intended that this variable be set once 5917 ** as part of process initialization and before any SQLite interface 5918 ** routines have been called and that this variable remain unchanged 5919 ** thereafter. 5920 ** 5921 ** ^The [temp_store_directory pragma] may modify this variable and cause 5922 ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 5923 ** the [temp_store_directory pragma] always assumes that any string 5924 ** that this variable points to is held in memory obtained from 5925 ** [sqlite3_malloc] and the pragma may attempt to free that memory 5926 ** using [sqlite3_free]. 5927 ** Hence, if this variable is modified directly, either it should be 5928 ** made NULL or made to point to memory obtained from [sqlite3_malloc] 5929 ** or else the use of the [temp_store_directory pragma] should be avoided. 5930 ** Except when requested by the [temp_store_directory pragma], SQLite 5931 ** does not free the memory that sqlite3_temp_directory points to. If 5932 ** the application wants that memory to be freed, it must do 5933 ** so itself, taking care to only do so after all [database connection] 5934 ** objects have been destroyed. 5935 ** 5936 ** <b>Note to Windows Runtime users:</b> The temporary directory must be set 5937 ** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various 5938 ** features that require the use of temporary files may fail. Here is an 5939 ** example of how to do this using C++ with the Windows Runtime: 5940 ** 5941 ** <blockquote><pre> 5942 ** LPCWSTR zPath = Windows::Storage::ApplicationData::Current-> 5943 ** TemporaryFolder->Path->Data(); 5944 ** char zPathBuf[MAX_PATH + 1]; 5945 ** memset(zPathBuf, 0, sizeof(zPathBuf)); 5946 ** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf), 5947 ** NULL, NULL); 5948 ** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf); 5949 ** </pre></blockquote> 5950 */ 5951 SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory; 5952 5953 /* 5954 ** CAPI3REF: Name Of The Folder Holding Database Files 5955 ** 5956 ** ^(If this global variable is made to point to a string which is 5957 ** the name of a folder (a.k.a. directory), then all database files 5958 ** specified with a relative pathname and created or accessed by 5959 ** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed 5960 ** to be relative to that directory.)^ ^If this variable is a NULL 5961 ** pointer, then SQLite assumes that all database files specified 5962 ** with a relative pathname are relative to the current directory 5963 ** for the process. Only the windows VFS makes use of this global 5964 ** variable; it is ignored by the unix VFS. 5965 ** 5966 ** Changing the value of this variable while a database connection is 5967 ** open can result in a corrupt database. 5968 ** 5969 ** It is not safe to read or modify this variable in more than one 5970 ** thread at a time. It is not safe to read or modify this variable 5971 ** if a [database connection] is being used at the same time in a separate 5972 ** thread. 5973 ** It is intended that this variable be set once 5974 ** as part of process initialization and before any SQLite interface 5975 ** routines have been called and that this variable remain unchanged 5976 ** thereafter. 5977 ** 5978 ** ^The [data_store_directory pragma] may modify this variable and cause 5979 ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 5980 ** the [data_store_directory pragma] always assumes that any string 5981 ** that this variable points to is held in memory obtained from 5982 ** [sqlite3_malloc] and the pragma may attempt to free that memory 5983 ** using [sqlite3_free]. 5984 ** Hence, if this variable is modified directly, either it should be 5985 ** made NULL or made to point to memory obtained from [sqlite3_malloc] 5986 ** or else the use of the [data_store_directory pragma] should be avoided. 5987 */ 5988 SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory; 5989 5990 /* 5991 ** CAPI3REF: Win32 Specific Interface 5992 ** 5993 ** These interfaces are available only on Windows. The 5994 ** [sqlite3_win32_set_directory] interface is used to set the value associated 5995 ** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to 5996 ** zValue, depending on the value of the type parameter. The zValue parameter 5997 ** should be NULL to cause the previous value to be freed via [sqlite3_free]; 5998 ** a non-NULL value will be copied into memory obtained from [sqlite3_malloc] 5999 ** prior to being used. The [sqlite3_win32_set_directory] interface returns 6000 ** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported, 6001 ** or [SQLITE_NOMEM] if memory could not be allocated. The value of the 6002 ** [sqlite3_data_directory] variable is intended to act as a replacement for 6003 ** the current directory on the sub-platforms of Win32 where that concept is 6004 ** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and 6005 ** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the 6006 ** sqlite3_win32_set_directory interface except the string parameter must be 6007 ** UTF-8 or UTF-16, respectively. 6008 */ 6009 SQLITE_API int sqlite3_win32_set_directory( 6010 unsigned long type, /* Identifier for directory being set or reset */ 6011 void *zValue /* New value for directory being set or reset */ 6012 ); 6013 SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue); 6014 SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue); 6015 6016 /* 6017 ** CAPI3REF: Win32 Directory Types 6018 ** 6019 ** These macros are only available on Windows. They define the allowed values 6020 ** for the type argument to the [sqlite3_win32_set_directory] interface. 6021 */ 6022 #define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1 6023 #define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2 6024 6025 /* 6026 ** CAPI3REF: Test For Auto-Commit Mode 6027 ** KEYWORDS: {autocommit mode} 6028 ** METHOD: sqlite3 6029 ** 6030 ** ^The sqlite3_get_autocommit() interface returns non-zero or 6031 ** zero if the given database connection is or is not in autocommit mode, 6032 ** respectively. ^Autocommit mode is on by default. 6033 ** ^Autocommit mode is disabled by a [BEGIN] statement. 6034 ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. 6035 ** 6036 ** If certain kinds of errors occur on a statement within a multi-statement 6037 ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], 6038 ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the 6039 ** transaction might be rolled back automatically. The only way to 6040 ** find out whether SQLite automatically rolled back the transaction after 6041 ** an error is to use this function. 6042 ** 6043 ** If another thread changes the autocommit status of the database 6044 ** connection while this routine is running, then the return value 6045 ** is undefined. 6046 */ 6047 SQLITE_API int sqlite3_get_autocommit(sqlite3*); 6048 6049 /* 6050 ** CAPI3REF: Find The Database Handle Of A Prepared Statement 6051 ** METHOD: sqlite3_stmt 6052 ** 6053 ** ^The sqlite3_db_handle interface returns the [database connection] handle 6054 ** to which a [prepared statement] belongs. ^The [database connection] 6055 ** returned by sqlite3_db_handle is the same [database connection] 6056 ** that was the first argument 6057 ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to 6058 ** create the statement in the first place. 6059 */ 6060 SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*); 6061 6062 /* 6063 ** CAPI3REF: Return The Filename For A Database Connection 6064 ** METHOD: sqlite3 6065 ** 6066 ** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename 6067 ** associated with database N of connection D. 6068 ** ^If there is no attached database N on the database 6069 ** connection D, or if database N is a temporary or in-memory database, then 6070 ** this function will return either a NULL pointer or an empty string. 6071 ** 6072 ** ^The string value returned by this routine is owned and managed by 6073 ** the database connection. ^The value will be valid until the database N 6074 ** is [DETACH]-ed or until the database connection closes. 6075 ** 6076 ** ^The filename returned by this function is the output of the 6077 ** xFullPathname method of the [VFS]. ^In other words, the filename 6078 ** will be an absolute pathname, even if the filename used 6079 ** to open the database originally was a URI or relative pathname. 6080 ** 6081 ** If the filename pointer returned by this routine is not NULL, then it 6082 ** can be used as the filename input parameter to these routines: 6083 ** <ul> 6084 ** <li> [sqlite3_uri_parameter()] 6085 ** <li> [sqlite3_uri_boolean()] 6086 ** <li> [sqlite3_uri_int64()] 6087 ** <li> [sqlite3_filename_database()] 6088 ** <li> [sqlite3_filename_journal()] 6089 ** <li> [sqlite3_filename_wal()] 6090 ** </ul> 6091 */ 6092 SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName); 6093 6094 /* 6095 ** CAPI3REF: Determine if a database is read-only 6096 ** METHOD: sqlite3 6097 ** 6098 ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N 6099 ** of connection D is read-only, 0 if it is read/write, or -1 if N is not 6100 ** the name of a database on connection D. 6101 */ 6102 SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName); 6103 6104 /* 6105 ** CAPI3REF: Find the next prepared statement 6106 ** METHOD: sqlite3 6107 ** 6108 ** ^This interface returns a pointer to the next [prepared statement] after 6109 ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL 6110 ** then this interface returns a pointer to the first prepared statement 6111 ** associated with the database connection pDb. ^If no prepared statement 6112 ** satisfies the conditions of this routine, it returns NULL. 6113 ** 6114 ** The [database connection] pointer D in a call to 6115 ** [sqlite3_next_stmt(D,S)] must refer to an open database 6116 ** connection and in particular must not be a NULL pointer. 6117 */ 6118 SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); 6119 6120 /* 6121 ** CAPI3REF: Commit And Rollback Notification Callbacks 6122 ** METHOD: sqlite3 6123 ** 6124 ** ^The sqlite3_commit_hook() interface registers a callback 6125 ** function to be invoked whenever a transaction is [COMMIT | committed]. 6126 ** ^Any callback set by a previous call to sqlite3_commit_hook() 6127 ** for the same database connection is overridden. 6128 ** ^The sqlite3_rollback_hook() interface registers a callback 6129 ** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. 6130 ** ^Any callback set by a previous call to sqlite3_rollback_hook() 6131 ** for the same database connection is overridden. 6132 ** ^The pArg argument is passed through to the callback. 6133 ** ^If the callback on a commit hook function returns non-zero, 6134 ** then the commit is converted into a rollback. 6135 ** 6136 ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions 6137 ** return the P argument from the previous call of the same function 6138 ** on the same [database connection] D, or NULL for 6139 ** the first call for each function on D. 6140 ** 6141 ** The commit and rollback hook callbacks are not reentrant. 6142 ** The callback implementation must not do anything that will modify 6143 ** the database connection that invoked the callback. Any actions 6144 ** to modify the database connection must be deferred until after the 6145 ** completion of the [sqlite3_step()] call that triggered the commit 6146 ** or rollback hook in the first place. 6147 ** Note that running any other SQL statements, including SELECT statements, 6148 ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify 6149 ** the database connections for the meaning of "modify" in this paragraph. 6150 ** 6151 ** ^Registering a NULL function disables the callback. 6152 ** 6153 ** ^When the commit hook callback routine returns zero, the [COMMIT] 6154 ** operation is allowed to continue normally. ^If the commit hook 6155 ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. 6156 ** ^The rollback hook is invoked on a rollback that results from a commit 6157 ** hook returning non-zero, just as it would be with any other rollback. 6158 ** 6159 ** ^For the purposes of this API, a transaction is said to have been 6160 ** rolled back if an explicit "ROLLBACK" statement is executed, or 6161 ** an error or constraint causes an implicit rollback to occur. 6162 ** ^The rollback callback is not invoked if a transaction is 6163 ** automatically rolled back because the database connection is closed. 6164 ** 6165 ** See also the [sqlite3_update_hook()] interface. 6166 */ 6167 SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); 6168 SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); 6169 6170 /* 6171 ** CAPI3REF: Data Change Notification Callbacks 6172 ** METHOD: sqlite3 6173 ** 6174 ** ^The sqlite3_update_hook() interface registers a callback function 6175 ** with the [database connection] identified by the first argument 6176 ** to be invoked whenever a row is updated, inserted or deleted in 6177 ** a [rowid table]. 6178 ** ^Any callback set by a previous call to this function 6179 ** for the same database connection is overridden. 6180 ** 6181 ** ^The second argument is a pointer to the function to invoke when a 6182 ** row is updated, inserted or deleted in a rowid table. 6183 ** ^The first argument to the callback is a copy of the third argument 6184 ** to sqlite3_update_hook(). 6185 ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], 6186 ** or [SQLITE_UPDATE], depending on the operation that caused the callback 6187 ** to be invoked. 6188 ** ^The third and fourth arguments to the callback contain pointers to the 6189 ** database and table name containing the affected row. 6190 ** ^The final callback parameter is the [rowid] of the row. 6191 ** ^In the case of an update, this is the [rowid] after the update takes place. 6192 ** 6193 ** ^(The update hook is not invoked when internal system tables are 6194 ** modified (i.e. sqlite_master and sqlite_sequence).)^ 6195 ** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. 6196 ** 6197 ** ^In the current implementation, the update hook 6198 ** is not invoked when conflicting rows are deleted because of an 6199 ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook 6200 ** invoked when rows are deleted using the [truncate optimization]. 6201 ** The exceptions defined in this paragraph might change in a future 6202 ** release of SQLite. 6203 ** 6204 ** The update hook implementation must not do anything that will modify 6205 ** the database connection that invoked the update hook. Any actions 6206 ** to modify the database connection must be deferred until after the 6207 ** completion of the [sqlite3_step()] call that triggered the update hook. 6208 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 6209 ** database connections for the meaning of "modify" in this paragraph. 6210 ** 6211 ** ^The sqlite3_update_hook(D,C,P) function 6212 ** returns the P argument from the previous call 6213 ** on the same [database connection] D, or NULL for 6214 ** the first call on D. 6215 ** 6216 ** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()], 6217 ** and [sqlite3_preupdate_hook()] interfaces. 6218 */ 6219 SQLITE_API void *sqlite3_update_hook( 6220 sqlite3*, 6221 void(*)(void *,int ,char const *,char const *,sqlite3_int64), 6222 void* 6223 ); 6224 6225 /* 6226 ** CAPI3REF: Enable Or Disable Shared Pager Cache 6227 ** 6228 ** ^(This routine enables or disables the sharing of the database cache 6229 ** and schema data structures between [database connection | connections] 6230 ** to the same database. Sharing is enabled if the argument is true 6231 ** and disabled if the argument is false.)^ 6232 ** 6233 ** ^Cache sharing is enabled and disabled for an entire process. 6234 ** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). 6235 ** In prior versions of SQLite, 6236 ** sharing was enabled or disabled for each thread separately. 6237 ** 6238 ** ^(The cache sharing mode set by this interface effects all subsequent 6239 ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. 6240 ** Existing database connections continue to use the sharing mode 6241 ** that was in effect at the time they were opened.)^ 6242 ** 6243 ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled 6244 ** successfully. An [error code] is returned otherwise.)^ 6245 ** 6246 ** ^Shared cache is disabled by default. It is recommended that it stay 6247 ** that way. In other words, do not use this routine. This interface 6248 ** continues to be provided for historical compatibility, but its use is 6249 ** discouraged. Any use of shared cache is discouraged. If shared cache 6250 ** must be used, it is recommended that shared cache only be enabled for 6251 ** individual database connections using the [sqlite3_open_v2()] interface 6252 ** with the [SQLITE_OPEN_SHAREDCACHE] flag. 6253 ** 6254 ** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0 6255 ** and will always return SQLITE_MISUSE. On those systems, 6256 ** shared cache mode should be enabled per-database connection via 6257 ** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE]. 6258 ** 6259 ** This interface is threadsafe on processors where writing a 6260 ** 32-bit integer is atomic. 6261 ** 6262 ** See Also: [SQLite Shared-Cache Mode] 6263 */ 6264 SQLITE_API int sqlite3_enable_shared_cache(int); 6265 6266 /* 6267 ** CAPI3REF: Attempt To Free Heap Memory 6268 ** 6269 ** ^The sqlite3_release_memory() interface attempts to free N bytes 6270 ** of heap memory by deallocating non-essential memory allocations 6271 ** held by the database library. Memory used to cache database 6272 ** pages to improve performance is an example of non-essential memory. 6273 ** ^sqlite3_release_memory() returns the number of bytes actually freed, 6274 ** which might be more or less than the amount requested. 6275 ** ^The sqlite3_release_memory() routine is a no-op returning zero 6276 ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. 6277 ** 6278 ** See also: [sqlite3_db_release_memory()] 6279 */ 6280 SQLITE_API int sqlite3_release_memory(int); 6281 6282 /* 6283 ** CAPI3REF: Free Memory Used By A Database Connection 6284 ** METHOD: sqlite3 6285 ** 6286 ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap 6287 ** memory as possible from database connection D. Unlike the 6288 ** [sqlite3_release_memory()] interface, this interface is in effect even 6289 ** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is 6290 ** omitted. 6291 ** 6292 ** See also: [sqlite3_release_memory()] 6293 */ 6294 SQLITE_API int sqlite3_db_release_memory(sqlite3*); 6295 6296 /* 6297 ** CAPI3REF: Impose A Limit On Heap Size 6298 ** 6299 ** These interfaces impose limits on the amount of heap memory that will be 6300 ** by all database connections within a single process. 6301 ** 6302 ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the 6303 ** soft limit on the amount of heap memory that may be allocated by SQLite. 6304 ** ^SQLite strives to keep heap memory utilization below the soft heap 6305 ** limit by reducing the number of pages held in the page cache 6306 ** as heap memory usages approaches the limit. 6307 ** ^The soft heap limit is "soft" because even though SQLite strives to stay 6308 ** below the limit, it will exceed the limit rather than generate 6309 ** an [SQLITE_NOMEM] error. In other words, the soft heap limit 6310 ** is advisory only. 6311 ** 6312 ** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of 6313 ** N bytes on the amount of memory that will be allocated. ^The 6314 ** sqlite3_hard_heap_limit64(N) interface is similar to 6315 ** sqlite3_soft_heap_limit64(N) except that memory allocations will fail 6316 ** when the hard heap limit is reached. 6317 ** 6318 ** ^The return value from both sqlite3_soft_heap_limit64() and 6319 ** sqlite3_hard_heap_limit64() is the size of 6320 ** the heap limit prior to the call, or negative in the case of an 6321 ** error. ^If the argument N is negative 6322 ** then no change is made to the heap limit. Hence, the current 6323 ** size of heap limits can be determined by invoking 6324 ** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1). 6325 ** 6326 ** ^Setting the heap limits to zero disables the heap limiter mechanism. 6327 ** 6328 ** ^The soft heap limit may not be greater than the hard heap limit. 6329 ** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N) 6330 ** is invoked with a value of N that is greater than the hard heap limit, 6331 ** the the soft heap limit is set to the value of the hard heap limit. 6332 ** ^The soft heap limit is automatically enabled whenever the hard heap 6333 ** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and 6334 ** the soft heap limit is outside the range of 1..N, then the soft heap 6335 ** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the 6336 ** hard heap limit is enabled makes the soft heap limit equal to the 6337 ** hard heap limit. 6338 ** 6339 ** The memory allocation limits can also be adjusted using 6340 ** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit]. 6341 ** 6342 ** ^(The heap limits are not enforced in the current implementation 6343 ** if one or more of following conditions are true: 6344 ** 6345 ** <ul> 6346 ** <li> The limit value is set to zero. 6347 ** <li> Memory accounting is disabled using a combination of the 6348 ** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and 6349 ** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option. 6350 ** <li> An alternative page cache implementation is specified using 6351 ** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...). 6352 ** <li> The page cache allocates from its own memory pool supplied 6353 ** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than 6354 ** from the heap. 6355 ** </ul>)^ 6356 ** 6357 ** The circumstances under which SQLite will enforce the heap limits may 6358 ** changes in future releases of SQLite. 6359 */ 6360 SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N); 6361 SQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N); 6362 6363 /* 6364 ** CAPI3REF: Deprecated Soft Heap Limit Interface 6365 ** DEPRECATED 6366 ** 6367 ** This is a deprecated version of the [sqlite3_soft_heap_limit64()] 6368 ** interface. This routine is provided for historical compatibility 6369 ** only. All new applications should use the 6370 ** [sqlite3_soft_heap_limit64()] interface rather than this one. 6371 */ 6372 SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N); 6373 6374 6375 /* 6376 ** CAPI3REF: Extract Metadata About A Column Of A Table 6377 ** METHOD: sqlite3 6378 ** 6379 ** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns 6380 ** information about column C of table T in database D 6381 ** on [database connection] X.)^ ^The sqlite3_table_column_metadata() 6382 ** interface returns SQLITE_OK and fills in the non-NULL pointers in 6383 ** the final five arguments with appropriate values if the specified 6384 ** column exists. ^The sqlite3_table_column_metadata() interface returns 6385 ** SQLITE_ERROR if the specified column does not exist. 6386 ** ^If the column-name parameter to sqlite3_table_column_metadata() is a 6387 ** NULL pointer, then this routine simply checks for the existence of the 6388 ** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it 6389 ** does not. If the table name parameter T in a call to 6390 ** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is 6391 ** undefined behavior. 6392 ** 6393 ** ^The column is identified by the second, third and fourth parameters to 6394 ** this function. ^(The second parameter is either the name of the database 6395 ** (i.e. "main", "temp", or an attached database) containing the specified 6396 ** table or NULL.)^ ^If it is NULL, then all attached databases are searched 6397 ** for the table using the same algorithm used by the database engine to 6398 ** resolve unqualified table references. 6399 ** 6400 ** ^The third and fourth parameters to this function are the table and column 6401 ** name of the desired column, respectively. 6402 ** 6403 ** ^Metadata is returned by writing to the memory locations passed as the 5th 6404 ** and subsequent parameters to this function. ^Any of these arguments may be 6405 ** NULL, in which case the corresponding element of metadata is omitted. 6406 ** 6407 ** ^(<blockquote> 6408 ** <table border="1"> 6409 ** <tr><th> Parameter <th> Output<br>Type <th> Description 6410 ** 6411 ** <tr><td> 5th <td> const char* <td> Data type 6412 ** <tr><td> 6th <td> const char* <td> Name of default collation sequence 6413 ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint 6414 ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY 6415 ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT] 6416 ** </table> 6417 ** </blockquote>)^ 6418 ** 6419 ** ^The memory pointed to by the character pointers returned for the 6420 ** declaration type and collation sequence is valid until the next 6421 ** call to any SQLite API function. 6422 ** 6423 ** ^If the specified table is actually a view, an [error code] is returned. 6424 ** 6425 ** ^If the specified column is "rowid", "oid" or "_rowid_" and the table 6426 ** is not a [WITHOUT ROWID] table and an 6427 ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output 6428 ** parameters are set for the explicitly declared column. ^(If there is no 6429 ** [INTEGER PRIMARY KEY] column, then the outputs 6430 ** for the [rowid] are set as follows: 6431 ** 6432 ** <pre> 6433 ** data type: "INTEGER" 6434 ** collation sequence: "BINARY" 6435 ** not null: 0 6436 ** primary key: 1 6437 ** auto increment: 0 6438 ** </pre>)^ 6439 ** 6440 ** ^This function causes all database schemas to be read from disk and 6441 ** parsed, if that has not already been done, and returns an error if 6442 ** any errors are encountered while loading the schema. 6443 */ 6444 SQLITE_API int sqlite3_table_column_metadata( 6445 sqlite3 *db, /* Connection handle */ 6446 const char *zDbName, /* Database name or NULL */ 6447 const char *zTableName, /* Table name */ 6448 const char *zColumnName, /* Column name */ 6449 char const **pzDataType, /* OUTPUT: Declared data type */ 6450 char const **pzCollSeq, /* OUTPUT: Collation sequence name */ 6451 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ 6452 int *pPrimaryKey, /* OUTPUT: True if column part of PK */ 6453 int *pAutoinc /* OUTPUT: True if column is auto-increment */ 6454 ); 6455 6456 /* 6457 ** CAPI3REF: Load An Extension 6458 ** METHOD: sqlite3 6459 ** 6460 ** ^This interface loads an SQLite extension library from the named file. 6461 ** 6462 ** ^The sqlite3_load_extension() interface attempts to load an 6463 ** [SQLite extension] library contained in the file zFile. If 6464 ** the file cannot be loaded directly, attempts are made to load 6465 ** with various operating-system specific extensions added. 6466 ** So for example, if "samplelib" cannot be loaded, then names like 6467 ** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might 6468 ** be tried also. 6469 ** 6470 ** ^The entry point is zProc. 6471 ** ^(zProc may be 0, in which case SQLite will try to come up with an 6472 ** entry point name on its own. It first tries "sqlite3_extension_init". 6473 ** If that does not work, it constructs a name "sqlite3_X_init" where the 6474 ** X is consists of the lower-case equivalent of all ASCII alphabetic 6475 ** characters in the filename from the last "/" to the first following 6476 ** "." and omitting any initial "lib".)^ 6477 ** ^The sqlite3_load_extension() interface returns 6478 ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. 6479 ** ^If an error occurs and pzErrMsg is not 0, then the 6480 ** [sqlite3_load_extension()] interface shall attempt to 6481 ** fill *pzErrMsg with error message text stored in memory 6482 ** obtained from [sqlite3_malloc()]. The calling function 6483 ** should free this memory by calling [sqlite3_free()]. 6484 ** 6485 ** ^Extension loading must be enabled using 6486 ** [sqlite3_enable_load_extension()] or 6487 ** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL) 6488 ** prior to calling this API, 6489 ** otherwise an error will be returned. 6490 ** 6491 ** <b>Security warning:</b> It is recommended that the 6492 ** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this 6493 ** interface. The use of the [sqlite3_enable_load_extension()] interface 6494 ** should be avoided. This will keep the SQL function [load_extension()] 6495 ** disabled and prevent SQL injections from giving attackers 6496 ** access to extension loading capabilities. 6497 ** 6498 ** See also the [load_extension() SQL function]. 6499 */ 6500 SQLITE_API int sqlite3_load_extension( 6501 sqlite3 *db, /* Load the extension into this database connection */ 6502 const char *zFile, /* Name of the shared library containing extension */ 6503 const char *zProc, /* Entry point. Derived from zFile if 0 */ 6504 char **pzErrMsg /* Put error message here if not 0 */ 6505 ); 6506 6507 /* 6508 ** CAPI3REF: Enable Or Disable Extension Loading 6509 ** METHOD: sqlite3 6510 ** 6511 ** ^So as not to open security holes in older applications that are 6512 ** unprepared to deal with [extension loading], and as a means of disabling 6513 ** [extension loading] while evaluating user-entered SQL, the following API 6514 ** is provided to turn the [sqlite3_load_extension()] mechanism on and off. 6515 ** 6516 ** ^Extension loading is off by default. 6517 ** ^Call the sqlite3_enable_load_extension() routine with onoff==1 6518 ** to turn extension loading on and call it with onoff==0 to turn 6519 ** it back off again. 6520 ** 6521 ** ^This interface enables or disables both the C-API 6522 ** [sqlite3_load_extension()] and the SQL function [load_extension()]. 6523 ** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..) 6524 ** to enable or disable only the C-API.)^ 6525 ** 6526 ** <b>Security warning:</b> It is recommended that extension loading 6527 ** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method 6528 ** rather than this interface, so the [load_extension()] SQL function 6529 ** remains disabled. This will prevent SQL injections from giving attackers 6530 ** access to extension loading capabilities. 6531 */ 6532 SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff); 6533 6534 /* 6535 ** CAPI3REF: Automatically Load Statically Linked Extensions 6536 ** 6537 ** ^This interface causes the xEntryPoint() function to be invoked for 6538 ** each new [database connection] that is created. The idea here is that 6539 ** xEntryPoint() is the entry point for a statically linked [SQLite extension] 6540 ** that is to be automatically loaded into all new database connections. 6541 ** 6542 ** ^(Even though the function prototype shows that xEntryPoint() takes 6543 ** no arguments and returns void, SQLite invokes xEntryPoint() with three 6544 ** arguments and expects an integer result as if the signature of the 6545 ** entry point where as follows: 6546 ** 6547 ** <blockquote><pre> 6548 ** int xEntryPoint( 6549 ** sqlite3 *db, 6550 ** const char **pzErrMsg, 6551 ** const struct sqlite3_api_routines *pThunk 6552 ** ); 6553 ** </pre></blockquote>)^ 6554 ** 6555 ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg 6556 ** point to an appropriate error message (obtained from [sqlite3_mprintf()]) 6557 ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg 6558 ** is NULL before calling the xEntryPoint(). ^SQLite will invoke 6559 ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any 6560 ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], 6561 ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. 6562 ** 6563 ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already 6564 ** on the list of automatic extensions is a harmless no-op. ^No entry point 6565 ** will be called more than once for each database connection that is opened. 6566 ** 6567 ** See also: [sqlite3_reset_auto_extension()] 6568 ** and [sqlite3_cancel_auto_extension()] 6569 */ 6570 SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void)); 6571 6572 /* 6573 ** CAPI3REF: Cancel Automatic Extension Loading 6574 ** 6575 ** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the 6576 ** initialization routine X that was registered using a prior call to 6577 ** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)] 6578 ** routine returns 1 if initialization routine X was successfully 6579 ** unregistered and it returns 0 if X was not on the list of initialization 6580 ** routines. 6581 */ 6582 SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void)); 6583 6584 /* 6585 ** CAPI3REF: Reset Automatic Extension Loading 6586 ** 6587 ** ^This interface disables all automatic extensions previously 6588 ** registered using [sqlite3_auto_extension()]. 6589 */ 6590 SQLITE_API void sqlite3_reset_auto_extension(void); 6591 6592 /* 6593 ** The interface to the virtual-table mechanism is currently considered 6594 ** to be experimental. The interface might change in incompatible ways. 6595 ** If this is a problem for you, do not use the interface at this time. 6596 ** 6597 ** When the virtual-table mechanism stabilizes, we will declare the 6598 ** interface fixed, support it indefinitely, and remove this comment. 6599 */ 6600 6601 /* 6602 ** Structures used by the virtual table interface 6603 */ 6604 typedef struct sqlite3_vtab sqlite3_vtab; 6605 typedef struct sqlite3_index_info sqlite3_index_info; 6606 typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; 6607 typedef struct sqlite3_module sqlite3_module; 6608 6609 /* 6610 ** CAPI3REF: Virtual Table Object 6611 ** KEYWORDS: sqlite3_module {virtual table module} 6612 ** 6613 ** This structure, sometimes called a "virtual table module", 6614 ** defines the implementation of a [virtual table]. 6615 ** This structure consists mostly of methods for the module. 6616 ** 6617 ** ^A virtual table module is created by filling in a persistent 6618 ** instance of this structure and passing a pointer to that instance 6619 ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. 6620 ** ^The registration remains valid until it is replaced by a different 6621 ** module or until the [database connection] closes. The content 6622 ** of this structure must not change while it is registered with 6623 ** any database connection. 6624 */ 6625 struct sqlite3_module { 6626 int iVersion; 6627 int (*xCreate)(sqlite3*, void *pAux, 6628 int argc, const char *const*argv, 6629 sqlite3_vtab **ppVTab, char**); 6630 int (*xConnect)(sqlite3*, void *pAux, 6631 int argc, const char *const*argv, 6632 sqlite3_vtab **ppVTab, char**); 6633 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); 6634 int (*xDisconnect)(sqlite3_vtab *pVTab); 6635 int (*xDestroy)(sqlite3_vtab *pVTab); 6636 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); 6637 int (*xClose)(sqlite3_vtab_cursor*); 6638 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, 6639 int argc, sqlite3_value **argv); 6640 int (*xNext)(sqlite3_vtab_cursor*); 6641 int (*xEof)(sqlite3_vtab_cursor*); 6642 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); 6643 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); 6644 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); 6645 int (*xBegin)(sqlite3_vtab *pVTab); 6646 int (*xSync)(sqlite3_vtab *pVTab); 6647 int (*xCommit)(sqlite3_vtab *pVTab); 6648 int (*xRollback)(sqlite3_vtab *pVTab); 6649 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, 6650 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), 6651 void **ppArg); 6652 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); 6653 /* The methods above are in version 1 of the sqlite_module object. Those 6654 ** below are for version 2 and greater. */ 6655 int (*xSavepoint)(sqlite3_vtab *pVTab, int); 6656 int (*xRelease)(sqlite3_vtab *pVTab, int); 6657 int (*xRollbackTo)(sqlite3_vtab *pVTab, int); 6658 /* The methods above are in versions 1 and 2 of the sqlite_module object. 6659 ** Those below are for version 3 and greater. */ 6660 int (*xShadowName)(const char*); 6661 }; 6662 6663 /* 6664 ** CAPI3REF: Virtual Table Indexing Information 6665 ** KEYWORDS: sqlite3_index_info 6666 ** 6667 ** The sqlite3_index_info structure and its substructures is used as part 6668 ** of the [virtual table] interface to 6669 ** pass information into and receive the reply from the [xBestIndex] 6670 ** method of a [virtual table module]. The fields under **Inputs** are the 6671 ** inputs to xBestIndex and are read-only. xBestIndex inserts its 6672 ** results into the **Outputs** fields. 6673 ** 6674 ** ^(The aConstraint[] array records WHERE clause constraints of the form: 6675 ** 6676 ** <blockquote>column OP expr</blockquote> 6677 ** 6678 ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is 6679 ** stored in aConstraint[].op using one of the 6680 ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ 6681 ** ^(The index of the column is stored in 6682 ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the 6683 ** expr on the right-hand side can be evaluated (and thus the constraint 6684 ** is usable) and false if it cannot.)^ 6685 ** 6686 ** ^The optimizer automatically inverts terms of the form "expr OP column" 6687 ** and makes other simplifications to the WHERE clause in an attempt to 6688 ** get as many WHERE clause terms into the form shown above as possible. 6689 ** ^The aConstraint[] array only reports WHERE clause terms that are 6690 ** relevant to the particular virtual table being queried. 6691 ** 6692 ** ^Information about the ORDER BY clause is stored in aOrderBy[]. 6693 ** ^Each term of aOrderBy records a column of the ORDER BY clause. 6694 ** 6695 ** The colUsed field indicates which columns of the virtual table may be 6696 ** required by the current scan. Virtual table columns are numbered from 6697 ** zero in the order in which they appear within the CREATE TABLE statement 6698 ** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62), 6699 ** the corresponding bit is set within the colUsed mask if the column may be 6700 ** required by SQLite. If the table has at least 64 columns and any column 6701 ** to the right of the first 63 is required, then bit 63 of colUsed is also 6702 ** set. In other words, column iCol may be required if the expression 6703 ** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to 6704 ** non-zero. 6705 ** 6706 ** The [xBestIndex] method must fill aConstraintUsage[] with information 6707 ** about what parameters to pass to xFilter. ^If argvIndex>0 then 6708 ** the right-hand side of the corresponding aConstraint[] is evaluated 6709 ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit 6710 ** is true, then the constraint is assumed to be fully handled by the 6711 ** virtual table and might not be checked again by the byte code.)^ ^(The 6712 ** aConstraintUsage[].omit flag is an optimization hint. When the omit flag 6713 ** is left in its default setting of false, the constraint will always be 6714 ** checked separately in byte code. If the omit flag is change to true, then 6715 ** the constraint may or may not be checked in byte code. In other words, 6716 ** when the omit flag is true there is no guarantee that the constraint will 6717 ** not be checked again using byte code.)^ 6718 ** 6719 ** ^The idxNum and idxPtr values are recorded and passed into the 6720 ** [xFilter] method. 6721 ** ^[sqlite3_free()] is used to free idxPtr if and only if 6722 ** needToFreeIdxPtr is true. 6723 ** 6724 ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in 6725 ** the correct order to satisfy the ORDER BY clause so that no separate 6726 ** sorting step is required. 6727 ** 6728 ** ^The estimatedCost value is an estimate of the cost of a particular 6729 ** strategy. A cost of N indicates that the cost of the strategy is similar 6730 ** to a linear scan of an SQLite table with N rows. A cost of log(N) 6731 ** indicates that the expense of the operation is similar to that of a 6732 ** binary search on a unique indexed field of an SQLite table with N rows. 6733 ** 6734 ** ^The estimatedRows value is an estimate of the number of rows that 6735 ** will be returned by the strategy. 6736 ** 6737 ** The xBestIndex method may optionally populate the idxFlags field with a 6738 ** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag - 6739 ** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite 6740 ** assumes that the strategy may visit at most one row. 6741 ** 6742 ** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then 6743 ** SQLite also assumes that if a call to the xUpdate() method is made as 6744 ** part of the same statement to delete or update a virtual table row and the 6745 ** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback 6746 ** any database changes. In other words, if the xUpdate() returns 6747 ** SQLITE_CONSTRAINT, the database contents must be exactly as they were 6748 ** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not 6749 ** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by 6750 ** the xUpdate method are automatically rolled back by SQLite. 6751 ** 6752 ** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info 6753 ** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). 6754 ** If a virtual table extension is 6755 ** used with an SQLite version earlier than 3.8.2, the results of attempting 6756 ** to read or write the estimatedRows field are undefined (but are likely 6757 ** to include crashing the application). The estimatedRows field should 6758 ** therefore only be used if [sqlite3_libversion_number()] returns a 6759 ** value greater than or equal to 3008002. Similarly, the idxFlags field 6760 ** was added for [version 3.9.0] ([dateof:3.9.0]). 6761 ** It may therefore only be used if 6762 ** sqlite3_libversion_number() returns a value greater than or equal to 6763 ** 3009000. 6764 */ 6765 struct sqlite3_index_info { 6766 /* Inputs */ 6767 int nConstraint; /* Number of entries in aConstraint */ 6768 struct sqlite3_index_constraint { 6769 int iColumn; /* Column constrained. -1 for ROWID */ 6770 unsigned char op; /* Constraint operator */ 6771 unsigned char usable; /* True if this constraint is usable */ 6772 int iTermOffset; /* Used internally - xBestIndex should ignore */ 6773 } *aConstraint; /* Table of WHERE clause constraints */ 6774 int nOrderBy; /* Number of terms in the ORDER BY clause */ 6775 struct sqlite3_index_orderby { 6776 int iColumn; /* Column number */ 6777 unsigned char desc; /* True for DESC. False for ASC. */ 6778 } *aOrderBy; /* The ORDER BY clause */ 6779 /* Outputs */ 6780 struct sqlite3_index_constraint_usage { 6781 int argvIndex; /* if >0, constraint is part of argv to xFilter */ 6782 unsigned char omit; /* Do not code a test for this constraint */ 6783 } *aConstraintUsage; 6784 int idxNum; /* Number used to identify the index */ 6785 char *idxStr; /* String, possibly obtained from sqlite3_malloc */ 6786 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ 6787 int orderByConsumed; /* True if output is already ordered */ 6788 double estimatedCost; /* Estimated cost of using this index */ 6789 /* Fields below are only available in SQLite 3.8.2 and later */ 6790 sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ 6791 /* Fields below are only available in SQLite 3.9.0 and later */ 6792 int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ 6793 /* Fields below are only available in SQLite 3.10.0 and later */ 6794 sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */ 6795 }; 6796 6797 /* 6798 ** CAPI3REF: Virtual Table Scan Flags 6799 ** 6800 ** Virtual table implementations are allowed to set the 6801 ** [sqlite3_index_info].idxFlags field to some combination of 6802 ** these bits. 6803 */ 6804 #define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */ 6805 6806 /* 6807 ** CAPI3REF: Virtual Table Constraint Operator Codes 6808 ** 6809 ** These macros define the allowed values for the 6810 ** [sqlite3_index_info].aConstraint[].op field. Each value represents 6811 ** an operator that is part of a constraint term in the wHERE clause of 6812 ** a query that uses a [virtual table]. 6813 */ 6814 #define SQLITE_INDEX_CONSTRAINT_EQ 2 6815 #define SQLITE_INDEX_CONSTRAINT_GT 4 6816 #define SQLITE_INDEX_CONSTRAINT_LE 8 6817 #define SQLITE_INDEX_CONSTRAINT_LT 16 6818 #define SQLITE_INDEX_CONSTRAINT_GE 32 6819 #define SQLITE_INDEX_CONSTRAINT_MATCH 64 6820 #define SQLITE_INDEX_CONSTRAINT_LIKE 65 6821 #define SQLITE_INDEX_CONSTRAINT_GLOB 66 6822 #define SQLITE_INDEX_CONSTRAINT_REGEXP 67 6823 #define SQLITE_INDEX_CONSTRAINT_NE 68 6824 #define SQLITE_INDEX_CONSTRAINT_ISNOT 69 6825 #define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70 6826 #define SQLITE_INDEX_CONSTRAINT_ISNULL 71 6827 #define SQLITE_INDEX_CONSTRAINT_IS 72 6828 #define SQLITE_INDEX_CONSTRAINT_FUNCTION 150 6829 6830 /* 6831 ** CAPI3REF: Register A Virtual Table Implementation 6832 ** METHOD: sqlite3 6833 ** 6834 ** ^These routines are used to register a new [virtual table module] name. 6835 ** ^Module names must be registered before 6836 ** creating a new [virtual table] using the module and before using a 6837 ** preexisting [virtual table] for the module. 6838 ** 6839 ** ^The module name is registered on the [database connection] specified 6840 ** by the first parameter. ^The name of the module is given by the 6841 ** second parameter. ^The third parameter is a pointer to 6842 ** the implementation of the [virtual table module]. ^The fourth 6843 ** parameter is an arbitrary client data pointer that is passed through 6844 ** into the [xCreate] and [xConnect] methods of the virtual table module 6845 ** when a new virtual table is be being created or reinitialized. 6846 ** 6847 ** ^The sqlite3_create_module_v2() interface has a fifth parameter which 6848 ** is a pointer to a destructor for the pClientData. ^SQLite will 6849 ** invoke the destructor function (if it is not NULL) when SQLite 6850 ** no longer needs the pClientData pointer. ^The destructor will also 6851 ** be invoked if the call to sqlite3_create_module_v2() fails. 6852 ** ^The sqlite3_create_module() 6853 ** interface is equivalent to sqlite3_create_module_v2() with a NULL 6854 ** destructor. 6855 ** 6856 ** ^If the third parameter (the pointer to the sqlite3_module object) is 6857 ** NULL then no new module is create and any existing modules with the 6858 ** same name are dropped. 6859 ** 6860 ** See also: [sqlite3_drop_modules()] 6861 */ 6862 SQLITE_API int sqlite3_create_module( 6863 sqlite3 *db, /* SQLite connection to register module with */ 6864 const char *zName, /* Name of the module */ 6865 const sqlite3_module *p, /* Methods for the module */ 6866 void *pClientData /* Client data for xCreate/xConnect */ 6867 ); 6868 SQLITE_API int sqlite3_create_module_v2( 6869 sqlite3 *db, /* SQLite connection to register module with */ 6870 const char *zName, /* Name of the module */ 6871 const sqlite3_module *p, /* Methods for the module */ 6872 void *pClientData, /* Client data for xCreate/xConnect */ 6873 void(*xDestroy)(void*) /* Module destructor function */ 6874 ); 6875 6876 /* 6877 ** CAPI3REF: Remove Unnecessary Virtual Table Implementations 6878 ** METHOD: sqlite3 6879 ** 6880 ** ^The sqlite3_drop_modules(D,L) interface removes all virtual 6881 ** table modules from database connection D except those named on list L. 6882 ** The L parameter must be either NULL or a pointer to an array of pointers 6883 ** to strings where the array is terminated by a single NULL pointer. 6884 ** ^If the L parameter is NULL, then all virtual table modules are removed. 6885 ** 6886 ** See also: [sqlite3_create_module()] 6887 */ 6888 SQLITE_API int sqlite3_drop_modules( 6889 sqlite3 *db, /* Remove modules from this connection */ 6890 const char **azKeep /* Except, do not remove the ones named here */ 6891 ); 6892 6893 /* 6894 ** CAPI3REF: Virtual Table Instance Object 6895 ** KEYWORDS: sqlite3_vtab 6896 ** 6897 ** Every [virtual table module] implementation uses a subclass 6898 ** of this object to describe a particular instance 6899 ** of the [virtual table]. Each subclass will 6900 ** be tailored to the specific needs of the module implementation. 6901 ** The purpose of this superclass is to define certain fields that are 6902 ** common to all module implementations. 6903 ** 6904 ** ^Virtual tables methods can set an error message by assigning a 6905 ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should 6906 ** take care that any prior string is freed by a call to [sqlite3_free()] 6907 ** prior to assigning a new string to zErrMsg. ^After the error message 6908 ** is delivered up to the client application, the string will be automatically 6909 ** freed by sqlite3_free() and the zErrMsg field will be zeroed. 6910 */ 6911 struct sqlite3_vtab { 6912 const sqlite3_module *pModule; /* The module for this virtual table */ 6913 int nRef; /* Number of open cursors */ 6914 char *zErrMsg; /* Error message from sqlite3_mprintf() */ 6915 /* Virtual table implementations will typically add additional fields */ 6916 }; 6917 6918 /* 6919 ** CAPI3REF: Virtual Table Cursor Object 6920 ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} 6921 ** 6922 ** Every [virtual table module] implementation uses a subclass of the 6923 ** following structure to describe cursors that point into the 6924 ** [virtual table] and are used 6925 ** to loop through the virtual table. Cursors are created using the 6926 ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed 6927 ** by the [sqlite3_module.xClose | xClose] method. Cursors are used 6928 ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods 6929 ** of the module. Each module implementation will define 6930 ** the content of a cursor structure to suit its own needs. 6931 ** 6932 ** This superclass exists in order to define fields of the cursor that 6933 ** are common to all implementations. 6934 */ 6935 struct sqlite3_vtab_cursor { 6936 sqlite3_vtab *pVtab; /* Virtual table of this cursor */ 6937 /* Virtual table implementations will typically add additional fields */ 6938 }; 6939 6940 /* 6941 ** CAPI3REF: Declare The Schema Of A Virtual Table 6942 ** 6943 ** ^The [xCreate] and [xConnect] methods of a 6944 ** [virtual table module] call this interface 6945 ** to declare the format (the names and datatypes of the columns) of 6946 ** the virtual tables they implement. 6947 */ 6948 SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL); 6949 6950 /* 6951 ** CAPI3REF: Overload A Function For A Virtual Table 6952 ** METHOD: sqlite3 6953 ** 6954 ** ^(Virtual tables can provide alternative implementations of functions 6955 ** using the [xFindFunction] method of the [virtual table module]. 6956 ** But global versions of those functions 6957 ** must exist in order to be overloaded.)^ 6958 ** 6959 ** ^(This API makes sure a global version of a function with a particular 6960 ** name and number of parameters exists. If no such function exists 6961 ** before this API is called, a new function is created.)^ ^The implementation 6962 ** of the new function always causes an exception to be thrown. So 6963 ** the new function is not good for anything by itself. Its only 6964 ** purpose is to be a placeholder function that can be overloaded 6965 ** by a [virtual table]. 6966 */ 6967 SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); 6968 6969 /* 6970 ** The interface to the virtual-table mechanism defined above (back up 6971 ** to a comment remarkably similar to this one) is currently considered 6972 ** to be experimental. The interface might change in incompatible ways. 6973 ** If this is a problem for you, do not use the interface at this time. 6974 ** 6975 ** When the virtual-table mechanism stabilizes, we will declare the 6976 ** interface fixed, support it indefinitely, and remove this comment. 6977 */ 6978 6979 /* 6980 ** CAPI3REF: A Handle To An Open BLOB 6981 ** KEYWORDS: {BLOB handle} {BLOB handles} 6982 ** 6983 ** An instance of this object represents an open BLOB on which 6984 ** [sqlite3_blob_open | incremental BLOB I/O] can be performed. 6985 ** ^Objects of this type are created by [sqlite3_blob_open()] 6986 ** and destroyed by [sqlite3_blob_close()]. 6987 ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces 6988 ** can be used to read or write small subsections of the BLOB. 6989 ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. 6990 */ 6991 typedef struct sqlite3_blob sqlite3_blob; 6992 6993 /* 6994 ** CAPI3REF: Open A BLOB For Incremental I/O 6995 ** METHOD: sqlite3 6996 ** CONSTRUCTOR: sqlite3_blob 6997 ** 6998 ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located 6999 ** in row iRow, column zColumn, table zTable in database zDb; 7000 ** in other words, the same BLOB that would be selected by: 7001 ** 7002 ** <pre> 7003 ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow; 7004 ** </pre>)^ 7005 ** 7006 ** ^(Parameter zDb is not the filename that contains the database, but 7007 ** rather the symbolic name of the database. For attached databases, this is 7008 ** the name that appears after the AS keyword in the [ATTACH] statement. 7009 ** For the main database file, the database name is "main". For TEMP 7010 ** tables, the database name is "temp".)^ 7011 ** 7012 ** ^If the flags parameter is non-zero, then the BLOB is opened for read 7013 ** and write access. ^If the flags parameter is zero, the BLOB is opened for 7014 ** read-only access. 7015 ** 7016 ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored 7017 ** in *ppBlob. Otherwise an [error code] is returned and, unless the error 7018 ** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided 7019 ** the API is not misused, it is always safe to call [sqlite3_blob_close()] 7020 ** on *ppBlob after this function it returns. 7021 ** 7022 ** This function fails with SQLITE_ERROR if any of the following are true: 7023 ** <ul> 7024 ** <li> ^(Database zDb does not exist)^, 7025 ** <li> ^(Table zTable does not exist within database zDb)^, 7026 ** <li> ^(Table zTable is a WITHOUT ROWID table)^, 7027 ** <li> ^(Column zColumn does not exist)^, 7028 ** <li> ^(Row iRow is not present in the table)^, 7029 ** <li> ^(The specified column of row iRow contains a value that is not 7030 ** a TEXT or BLOB value)^, 7031 ** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE 7032 ** constraint and the blob is being opened for read/write access)^, 7033 ** <li> ^([foreign key constraints | Foreign key constraints] are enabled, 7034 ** column zColumn is part of a [child key] definition and the blob is 7035 ** being opened for read/write access)^. 7036 ** </ul> 7037 ** 7038 ** ^Unless it returns SQLITE_MISUSE, this function sets the 7039 ** [database connection] error code and message accessible via 7040 ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 7041 ** 7042 ** A BLOB referenced by sqlite3_blob_open() may be read using the 7043 ** [sqlite3_blob_read()] interface and modified by using 7044 ** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a 7045 ** different row of the same table using the [sqlite3_blob_reopen()] 7046 ** interface. However, the column, table, or database of a [BLOB handle] 7047 ** cannot be changed after the [BLOB handle] is opened. 7048 ** 7049 ** ^(If the row that a BLOB handle points to is modified by an 7050 ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects 7051 ** then the BLOB handle is marked as "expired". 7052 ** This is true if any column of the row is changed, even a column 7053 ** other than the one the BLOB handle is open on.)^ 7054 ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for 7055 ** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. 7056 ** ^(Changes written into a BLOB prior to the BLOB expiring are not 7057 ** rolled back by the expiration of the BLOB. Such changes will eventually 7058 ** commit if the transaction continues to completion.)^ 7059 ** 7060 ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of 7061 ** the opened blob. ^The size of a blob may not be changed by this 7062 ** interface. Use the [UPDATE] SQL command to change the size of a 7063 ** blob. 7064 ** 7065 ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces 7066 ** and the built-in [zeroblob] SQL function may be used to create a 7067 ** zero-filled blob to read or write using the incremental-blob interface. 7068 ** 7069 ** To avoid a resource leak, every open [BLOB handle] should eventually 7070 ** be released by a call to [sqlite3_blob_close()]. 7071 ** 7072 ** See also: [sqlite3_blob_close()], 7073 ** [sqlite3_blob_reopen()], [sqlite3_blob_read()], 7074 ** [sqlite3_blob_bytes()], [sqlite3_blob_write()]. 7075 */ 7076 SQLITE_API int sqlite3_blob_open( 7077 sqlite3*, 7078 const char *zDb, 7079 const char *zTable, 7080 const char *zColumn, 7081 sqlite3_int64 iRow, 7082 int flags, 7083 sqlite3_blob **ppBlob 7084 ); 7085 7086 /* 7087 ** CAPI3REF: Move a BLOB Handle to a New Row 7088 ** METHOD: sqlite3_blob 7089 ** 7090 ** ^This function is used to move an existing [BLOB handle] so that it points 7091 ** to a different row of the same database table. ^The new row is identified 7092 ** by the rowid value passed as the second argument. Only the row can be 7093 ** changed. ^The database, table and column on which the blob handle is open 7094 ** remain the same. Moving an existing [BLOB handle] to a new row is 7095 ** faster than closing the existing handle and opening a new one. 7096 ** 7097 ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - 7098 ** it must exist and there must be either a blob or text value stored in 7099 ** the nominated column.)^ ^If the new row is not present in the table, or if 7100 ** it does not contain a blob or text value, or if another error occurs, an 7101 ** SQLite error code is returned and the blob handle is considered aborted. 7102 ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or 7103 ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return 7104 ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle 7105 ** always returns zero. 7106 ** 7107 ** ^This function sets the database handle error code and message. 7108 */ 7109 SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); 7110 7111 /* 7112 ** CAPI3REF: Close A BLOB Handle 7113 ** DESTRUCTOR: sqlite3_blob 7114 ** 7115 ** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed 7116 ** unconditionally. Even if this routine returns an error code, the 7117 ** handle is still closed.)^ 7118 ** 7119 ** ^If the blob handle being closed was opened for read-write access, and if 7120 ** the database is in auto-commit mode and there are no other open read-write 7121 ** blob handles or active write statements, the current transaction is 7122 ** committed. ^If an error occurs while committing the transaction, an error 7123 ** code is returned and the transaction rolled back. 7124 ** 7125 ** Calling this function with an argument that is not a NULL pointer or an 7126 ** open blob handle results in undefined behaviour. ^Calling this routine 7127 ** with a null pointer (such as would be returned by a failed call to 7128 ** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function 7129 ** is passed a valid open blob handle, the values returned by the 7130 ** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning. 7131 */ 7132 SQLITE_API int sqlite3_blob_close(sqlite3_blob *); 7133 7134 /* 7135 ** CAPI3REF: Return The Size Of An Open BLOB 7136 ** METHOD: sqlite3_blob 7137 ** 7138 ** ^Returns the size in bytes of the BLOB accessible via the 7139 ** successfully opened [BLOB handle] in its only argument. ^The 7140 ** incremental blob I/O routines can only read or overwriting existing 7141 ** blob content; they cannot change the size of a blob. 7142 ** 7143 ** This routine only works on a [BLOB handle] which has been created 7144 ** by a prior successful call to [sqlite3_blob_open()] and which has not 7145 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7146 ** to this routine results in undefined and probably undesirable behavior. 7147 */ 7148 SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *); 7149 7150 /* 7151 ** CAPI3REF: Read Data From A BLOB Incrementally 7152 ** METHOD: sqlite3_blob 7153 ** 7154 ** ^(This function is used to read data from an open [BLOB handle] into a 7155 ** caller-supplied buffer. N bytes of data are copied into buffer Z 7156 ** from the open BLOB, starting at offset iOffset.)^ 7157 ** 7158 ** ^If offset iOffset is less than N bytes from the end of the BLOB, 7159 ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is 7160 ** less than zero, [SQLITE_ERROR] is returned and no data is read. 7161 ** ^The size of the blob (and hence the maximum value of N+iOffset) 7162 ** can be determined using the [sqlite3_blob_bytes()] interface. 7163 ** 7164 ** ^An attempt to read from an expired [BLOB handle] fails with an 7165 ** error code of [SQLITE_ABORT]. 7166 ** 7167 ** ^(On success, sqlite3_blob_read() returns SQLITE_OK. 7168 ** Otherwise, an [error code] or an [extended error code] is returned.)^ 7169 ** 7170 ** This routine only works on a [BLOB handle] which has been created 7171 ** by a prior successful call to [sqlite3_blob_open()] and which has not 7172 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7173 ** to this routine results in undefined and probably undesirable behavior. 7174 ** 7175 ** See also: [sqlite3_blob_write()]. 7176 */ 7177 SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); 7178 7179 /* 7180 ** CAPI3REF: Write Data Into A BLOB Incrementally 7181 ** METHOD: sqlite3_blob 7182 ** 7183 ** ^(This function is used to write data into an open [BLOB handle] from a 7184 ** caller-supplied buffer. N bytes of data are copied from the buffer Z 7185 ** into the open BLOB, starting at offset iOffset.)^ 7186 ** 7187 ** ^(On success, sqlite3_blob_write() returns SQLITE_OK. 7188 ** Otherwise, an [error code] or an [extended error code] is returned.)^ 7189 ** ^Unless SQLITE_MISUSE is returned, this function sets the 7190 ** [database connection] error code and message accessible via 7191 ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 7192 ** 7193 ** ^If the [BLOB handle] passed as the first argument was not opened for 7194 ** writing (the flags parameter to [sqlite3_blob_open()] was zero), 7195 ** this function returns [SQLITE_READONLY]. 7196 ** 7197 ** This function may only modify the contents of the BLOB; it is 7198 ** not possible to increase the size of a BLOB using this API. 7199 ** ^If offset iOffset is less than N bytes from the end of the BLOB, 7200 ** [SQLITE_ERROR] is returned and no data is written. The size of the 7201 ** BLOB (and hence the maximum value of N+iOffset) can be determined 7202 ** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less 7203 ** than zero [SQLITE_ERROR] is returned and no data is written. 7204 ** 7205 ** ^An attempt to write to an expired [BLOB handle] fails with an 7206 ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred 7207 ** before the [BLOB handle] expired are not rolled back by the 7208 ** expiration of the handle, though of course those changes might 7209 ** have been overwritten by the statement that expired the BLOB handle 7210 ** or by other independent statements. 7211 ** 7212 ** This routine only works on a [BLOB handle] which has been created 7213 ** by a prior successful call to [sqlite3_blob_open()] and which has not 7214 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7215 ** to this routine results in undefined and probably undesirable behavior. 7216 ** 7217 ** See also: [sqlite3_blob_read()]. 7218 */ 7219 SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); 7220 7221 /* 7222 ** CAPI3REF: Virtual File System Objects 7223 ** 7224 ** A virtual filesystem (VFS) is an [sqlite3_vfs] object 7225 ** that SQLite uses to interact 7226 ** with the underlying operating system. Most SQLite builds come with a 7227 ** single default VFS that is appropriate for the host computer. 7228 ** New VFSes can be registered and existing VFSes can be unregistered. 7229 ** The following interfaces are provided. 7230 ** 7231 ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. 7232 ** ^Names are case sensitive. 7233 ** ^Names are zero-terminated UTF-8 strings. 7234 ** ^If there is no match, a NULL pointer is returned. 7235 ** ^If zVfsName is NULL then the default VFS is returned. 7236 ** 7237 ** ^New VFSes are registered with sqlite3_vfs_register(). 7238 ** ^Each new VFS becomes the default VFS if the makeDflt flag is set. 7239 ** ^The same VFS can be registered multiple times without injury. 7240 ** ^To make an existing VFS into the default VFS, register it again 7241 ** with the makeDflt flag set. If two different VFSes with the 7242 ** same name are registered, the behavior is undefined. If a 7243 ** VFS is registered with a name that is NULL or an empty string, 7244 ** then the behavior is undefined. 7245 ** 7246 ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. 7247 ** ^(If the default VFS is unregistered, another VFS is chosen as 7248 ** the default. The choice for the new VFS is arbitrary.)^ 7249 */ 7250 SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); 7251 SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); 7252 SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*); 7253 7254 /* 7255 ** CAPI3REF: Mutexes 7256 ** 7257 ** The SQLite core uses these routines for thread 7258 ** synchronization. Though they are intended for internal 7259 ** use by SQLite, code that links against SQLite is 7260 ** permitted to use any of these routines. 7261 ** 7262 ** The SQLite source code contains multiple implementations 7263 ** of these mutex routines. An appropriate implementation 7264 ** is selected automatically at compile-time. The following 7265 ** implementations are available in the SQLite core: 7266 ** 7267 ** <ul> 7268 ** <li> SQLITE_MUTEX_PTHREADS 7269 ** <li> SQLITE_MUTEX_W32 7270 ** <li> SQLITE_MUTEX_NOOP 7271 ** </ul> 7272 ** 7273 ** The SQLITE_MUTEX_NOOP implementation is a set of routines 7274 ** that does no real locking and is appropriate for use in 7275 ** a single-threaded application. The SQLITE_MUTEX_PTHREADS and 7276 ** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix 7277 ** and Windows. 7278 ** 7279 ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor 7280 ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex 7281 ** implementation is included with the library. In this case the 7282 ** application must supply a custom mutex implementation using the 7283 ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function 7284 ** before calling sqlite3_initialize() or any other public sqlite3_ 7285 ** function that calls sqlite3_initialize(). 7286 ** 7287 ** ^The sqlite3_mutex_alloc() routine allocates a new 7288 ** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc() 7289 ** routine returns NULL if it is unable to allocate the requested 7290 ** mutex. The argument to sqlite3_mutex_alloc() must one of these 7291 ** integer constants: 7292 ** 7293 ** <ul> 7294 ** <li> SQLITE_MUTEX_FAST 7295 ** <li> SQLITE_MUTEX_RECURSIVE 7296 ** <li> SQLITE_MUTEX_STATIC_MASTER 7297 ** <li> SQLITE_MUTEX_STATIC_MEM 7298 ** <li> SQLITE_MUTEX_STATIC_OPEN 7299 ** <li> SQLITE_MUTEX_STATIC_PRNG 7300 ** <li> SQLITE_MUTEX_STATIC_LRU 7301 ** <li> SQLITE_MUTEX_STATIC_PMEM 7302 ** <li> SQLITE_MUTEX_STATIC_APP1 7303 ** <li> SQLITE_MUTEX_STATIC_APP2 7304 ** <li> SQLITE_MUTEX_STATIC_APP3 7305 ** <li> SQLITE_MUTEX_STATIC_VFS1 7306 ** <li> SQLITE_MUTEX_STATIC_VFS2 7307 ** <li> SQLITE_MUTEX_STATIC_VFS3 7308 ** </ul> 7309 ** 7310 ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) 7311 ** cause sqlite3_mutex_alloc() to create 7312 ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE 7313 ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. 7314 ** The mutex implementation does not need to make a distinction 7315 ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does 7316 ** not want to. SQLite will only request a recursive mutex in 7317 ** cases where it really needs one. If a faster non-recursive mutex 7318 ** implementation is available on the host platform, the mutex subsystem 7319 ** might return such a mutex in response to SQLITE_MUTEX_FAST. 7320 ** 7321 ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other 7322 ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return 7323 ** a pointer to a static preexisting mutex. ^Nine static mutexes are 7324 ** used by the current version of SQLite. Future versions of SQLite 7325 ** may add additional static mutexes. Static mutexes are for internal 7326 ** use by SQLite only. Applications that use SQLite mutexes should 7327 ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or 7328 ** SQLITE_MUTEX_RECURSIVE. 7329 ** 7330 ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST 7331 ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() 7332 ** returns a different mutex on every call. ^For the static 7333 ** mutex types, the same mutex is returned on every call that has 7334 ** the same type number. 7335 ** 7336 ** ^The sqlite3_mutex_free() routine deallocates a previously 7337 ** allocated dynamic mutex. Attempting to deallocate a static 7338 ** mutex results in undefined behavior. 7339 ** 7340 ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt 7341 ** to enter a mutex. ^If another thread is already within the mutex, 7342 ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return 7343 ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] 7344 ** upon successful entry. ^(Mutexes created using 7345 ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. 7346 ** In such cases, the 7347 ** mutex must be exited an equal number of times before another thread 7348 ** can enter.)^ If the same thread tries to enter any mutex other 7349 ** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined. 7350 ** 7351 ** ^(Some systems (for example, Windows 95) do not support the operation 7352 ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() 7353 ** will always return SQLITE_BUSY. The SQLite core only ever uses 7354 ** sqlite3_mutex_try() as an optimization so this is acceptable 7355 ** behavior.)^ 7356 ** 7357 ** ^The sqlite3_mutex_leave() routine exits a mutex that was 7358 ** previously entered by the same thread. The behavior 7359 ** is undefined if the mutex is not currently entered by the 7360 ** calling thread or is not currently allocated. 7361 ** 7362 ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or 7363 ** sqlite3_mutex_leave() is a NULL pointer, then all three routines 7364 ** behave as no-ops. 7365 ** 7366 ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. 7367 */ 7368 SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int); 7369 SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*); 7370 SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*); 7371 SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*); 7372 SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*); 7373 7374 /* 7375 ** CAPI3REF: Mutex Methods Object 7376 ** 7377 ** An instance of this structure defines the low-level routines 7378 ** used to allocate and use mutexes. 7379 ** 7380 ** Usually, the default mutex implementations provided by SQLite are 7381 ** sufficient, however the application has the option of substituting a custom 7382 ** implementation for specialized deployments or systems for which SQLite 7383 ** does not provide a suitable implementation. In this case, the application 7384 ** creates and populates an instance of this structure to pass 7385 ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. 7386 ** Additionally, an instance of this structure can be used as an 7387 ** output variable when querying the system for the current mutex 7388 ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. 7389 ** 7390 ** ^The xMutexInit method defined by this structure is invoked as 7391 ** part of system initialization by the sqlite3_initialize() function. 7392 ** ^The xMutexInit routine is called by SQLite exactly once for each 7393 ** effective call to [sqlite3_initialize()]. 7394 ** 7395 ** ^The xMutexEnd method defined by this structure is invoked as 7396 ** part of system shutdown by the sqlite3_shutdown() function. The 7397 ** implementation of this method is expected to release all outstanding 7398 ** resources obtained by the mutex methods implementation, especially 7399 ** those obtained by the xMutexInit method. ^The xMutexEnd() 7400 ** interface is invoked exactly once for each call to [sqlite3_shutdown()]. 7401 ** 7402 ** ^(The remaining seven methods defined by this structure (xMutexAlloc, 7403 ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and 7404 ** xMutexNotheld) implement the following interfaces (respectively): 7405 ** 7406 ** <ul> 7407 ** <li> [sqlite3_mutex_alloc()] </li> 7408 ** <li> [sqlite3_mutex_free()] </li> 7409 ** <li> [sqlite3_mutex_enter()] </li> 7410 ** <li> [sqlite3_mutex_try()] </li> 7411 ** <li> [sqlite3_mutex_leave()] </li> 7412 ** <li> [sqlite3_mutex_held()] </li> 7413 ** <li> [sqlite3_mutex_notheld()] </li> 7414 ** </ul>)^ 7415 ** 7416 ** The only difference is that the public sqlite3_XXX functions enumerated 7417 ** above silently ignore any invocations that pass a NULL pointer instead 7418 ** of a valid mutex handle. The implementations of the methods defined 7419 ** by this structure are not required to handle this case. The results 7420 ** of passing a NULL pointer instead of a valid mutex handle are undefined 7421 ** (i.e. it is acceptable to provide an implementation that segfaults if 7422 ** it is passed a NULL pointer). 7423 ** 7424 ** The xMutexInit() method must be threadsafe. It must be harmless to 7425 ** invoke xMutexInit() multiple times within the same process and without 7426 ** intervening calls to xMutexEnd(). Second and subsequent calls to 7427 ** xMutexInit() must be no-ops. 7428 ** 7429 ** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] 7430 ** and its associates). Similarly, xMutexAlloc() must not use SQLite memory 7431 ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite 7432 ** memory allocation for a fast or recursive mutex. 7433 ** 7434 ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is 7435 ** called, but only if the prior call to xMutexInit returned SQLITE_OK. 7436 ** If xMutexInit fails in any way, it is expected to clean up after itself 7437 ** prior to returning. 7438 */ 7439 typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; 7440 struct sqlite3_mutex_methods { 7441 int (*xMutexInit)(void); 7442 int (*xMutexEnd)(void); 7443 sqlite3_mutex *(*xMutexAlloc)(int); 7444 void (*xMutexFree)(sqlite3_mutex *); 7445 void (*xMutexEnter)(sqlite3_mutex *); 7446 int (*xMutexTry)(sqlite3_mutex *); 7447 void (*xMutexLeave)(sqlite3_mutex *); 7448 int (*xMutexHeld)(sqlite3_mutex *); 7449 int (*xMutexNotheld)(sqlite3_mutex *); 7450 }; 7451 7452 /* 7453 ** CAPI3REF: Mutex Verification Routines 7454 ** 7455 ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines 7456 ** are intended for use inside assert() statements. The SQLite core 7457 ** never uses these routines except inside an assert() and applications 7458 ** are advised to follow the lead of the core. The SQLite core only 7459 ** provides implementations for these routines when it is compiled 7460 ** with the SQLITE_DEBUG flag. External mutex implementations 7461 ** are only required to provide these routines if SQLITE_DEBUG is 7462 ** defined and if NDEBUG is not defined. 7463 ** 7464 ** These routines should return true if the mutex in their argument 7465 ** is held or not held, respectively, by the calling thread. 7466 ** 7467 ** The implementation is not required to provide versions of these 7468 ** routines that actually work. If the implementation does not provide working 7469 ** versions of these routines, it should at least provide stubs that always 7470 ** return true so that one does not get spurious assertion failures. 7471 ** 7472 ** If the argument to sqlite3_mutex_held() is a NULL pointer then 7473 ** the routine should return 1. This seems counter-intuitive since 7474 ** clearly the mutex cannot be held if it does not exist. But 7475 ** the reason the mutex does not exist is because the build is not 7476 ** using mutexes. And we do not want the assert() containing the 7477 ** call to sqlite3_mutex_held() to fail, so a non-zero return is 7478 ** the appropriate thing to do. The sqlite3_mutex_notheld() 7479 ** interface should also return 1 when given a NULL pointer. 7480 */ 7481 #ifndef NDEBUG 7482 SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*); 7483 SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*); 7484 #endif 7485 7486 /* 7487 ** CAPI3REF: Mutex Types 7488 ** 7489 ** The [sqlite3_mutex_alloc()] interface takes a single argument 7490 ** which is one of these integer constants. 7491 ** 7492 ** The set of static mutexes may change from one SQLite release to the 7493 ** next. Applications that override the built-in mutex logic must be 7494 ** prepared to accommodate additional static mutexes. 7495 */ 7496 #define SQLITE_MUTEX_FAST 0 7497 #define SQLITE_MUTEX_RECURSIVE 1 7498 #define SQLITE_MUTEX_STATIC_MASTER 2 7499 #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ 7500 #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ 7501 #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ 7502 #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */ 7503 #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ 7504 #define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ 7505 #define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ 7506 #define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */ 7507 #define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */ 7508 #define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */ 7509 #define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */ 7510 #define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */ 7511 #define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */ 7512 7513 /* 7514 ** CAPI3REF: Retrieve the mutex for a database connection 7515 ** METHOD: sqlite3 7516 ** 7517 ** ^This interface returns a pointer the [sqlite3_mutex] object that 7518 ** serializes access to the [database connection] given in the argument 7519 ** when the [threading mode] is Serialized. 7520 ** ^If the [threading mode] is Single-thread or Multi-thread then this 7521 ** routine returns a NULL pointer. 7522 */ 7523 SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*); 7524 7525 /* 7526 ** CAPI3REF: Low-Level Control Of Database Files 7527 ** METHOD: sqlite3 7528 ** KEYWORDS: {file control} 7529 ** 7530 ** ^The [sqlite3_file_control()] interface makes a direct call to the 7531 ** xFileControl method for the [sqlite3_io_methods] object associated 7532 ** with a particular database identified by the second argument. ^The 7533 ** name of the database is "main" for the main database or "temp" for the 7534 ** TEMP database, or the name that appears after the AS keyword for 7535 ** databases that are added using the [ATTACH] SQL command. 7536 ** ^A NULL pointer can be used in place of "main" to refer to the 7537 ** main database file. 7538 ** ^The third and fourth parameters to this routine 7539 ** are passed directly through to the second and third parameters of 7540 ** the xFileControl method. ^The return value of the xFileControl 7541 ** method becomes the return value of this routine. 7542 ** 7543 ** A few opcodes for [sqlite3_file_control()] are handled directly 7544 ** by the SQLite core and never invoke the 7545 ** sqlite3_io_methods.xFileControl method. 7546 ** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes 7547 ** a pointer to the underlying [sqlite3_file] object to be written into 7548 ** the space pointed to by the 4th parameter. The 7549 ** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns 7550 ** the [sqlite3_file] object associated with the journal file instead of 7551 ** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns 7552 ** a pointer to the underlying [sqlite3_vfs] object for the file. 7553 ** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter 7554 ** from the pager. 7555 ** 7556 ** ^If the second parameter (zDbName) does not match the name of any 7557 ** open database file, then SQLITE_ERROR is returned. ^This error 7558 ** code is not remembered and will not be recalled by [sqlite3_errcode()] 7559 ** or [sqlite3_errmsg()]. The underlying xFileControl method might 7560 ** also return SQLITE_ERROR. There is no way to distinguish between 7561 ** an incorrect zDbName and an SQLITE_ERROR return from the underlying 7562 ** xFileControl method. 7563 ** 7564 ** See also: [file control opcodes] 7565 */ 7566 SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); 7567 7568 /* 7569 ** CAPI3REF: Testing Interface 7570 ** 7571 ** ^The sqlite3_test_control() interface is used to read out internal 7572 ** state of SQLite and to inject faults into SQLite for testing 7573 ** purposes. ^The first parameter is an operation code that determines 7574 ** the number, meaning, and operation of all subsequent parameters. 7575 ** 7576 ** This interface is not for use by applications. It exists solely 7577 ** for verifying the correct operation of the SQLite library. Depending 7578 ** on how the SQLite library is compiled, this interface might not exist. 7579 ** 7580 ** The details of the operation codes, their meanings, the parameters 7581 ** they take, and what they do are all subject to change without notice. 7582 ** Unlike most of the SQLite API, this function is not guaranteed to 7583 ** operate consistently from one release to the next. 7584 */ 7585 SQLITE_API int sqlite3_test_control(int op, ...); 7586 7587 /* 7588 ** CAPI3REF: Testing Interface Operation Codes 7589 ** 7590 ** These constants are the valid operation code parameters used 7591 ** as the first argument to [sqlite3_test_control()]. 7592 ** 7593 ** These parameters and their meanings are subject to change 7594 ** without notice. These values are for testing purposes only. 7595 ** Applications should not use any of these parameters or the 7596 ** [sqlite3_test_control()] interface. 7597 */ 7598 #define SQLITE_TESTCTRL_FIRST 5 7599 #define SQLITE_TESTCTRL_PRNG_SAVE 5 7600 #define SQLITE_TESTCTRL_PRNG_RESTORE 6 7601 #define SQLITE_TESTCTRL_PRNG_RESET 7 /* NOT USED */ 7602 #define SQLITE_TESTCTRL_BITVEC_TEST 8 7603 #define SQLITE_TESTCTRL_FAULT_INSTALL 9 7604 #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 7605 #define SQLITE_TESTCTRL_PENDING_BYTE 11 7606 #define SQLITE_TESTCTRL_ASSERT 12 7607 #define SQLITE_TESTCTRL_ALWAYS 13 7608 #define SQLITE_TESTCTRL_RESERVE 14 7609 #define SQLITE_TESTCTRL_OPTIMIZATIONS 15 7610 #define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */ 7611 #define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */ 7612 #define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS 17 7613 #define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 7614 #define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */ 7615 #define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19 7616 #define SQLITE_TESTCTRL_NEVER_CORRUPT 20 7617 #define SQLITE_TESTCTRL_VDBE_COVERAGE 21 7618 #define SQLITE_TESTCTRL_BYTEORDER 22 7619 #define SQLITE_TESTCTRL_ISINIT 23 7620 #define SQLITE_TESTCTRL_SORTER_MMAP 24 7621 #define SQLITE_TESTCTRL_IMPOSTER 25 7622 #define SQLITE_TESTCTRL_PARSER_COVERAGE 26 7623 #define SQLITE_TESTCTRL_RESULT_INTREAL 27 7624 #define SQLITE_TESTCTRL_PRNG_SEED 28 7625 #define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS 29 7626 #define SQLITE_TESTCTRL_LAST 29 /* Largest TESTCTRL */ 7627 7628 /* 7629 ** CAPI3REF: SQL Keyword Checking 7630 ** 7631 ** These routines provide access to the set of SQL language keywords 7632 ** recognized by SQLite. Applications can uses these routines to determine 7633 ** whether or not a specific identifier needs to be escaped (for example, 7634 ** by enclosing in double-quotes) so as not to confuse the parser. 7635 ** 7636 ** The sqlite3_keyword_count() interface returns the number of distinct 7637 ** keywords understood by SQLite. 7638 ** 7639 ** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and 7640 ** makes *Z point to that keyword expressed as UTF8 and writes the number 7641 ** of bytes in the keyword into *L. The string that *Z points to is not 7642 ** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns 7643 ** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z 7644 ** or L are NULL or invalid pointers then calls to 7645 ** sqlite3_keyword_name(N,Z,L) result in undefined behavior. 7646 ** 7647 ** The sqlite3_keyword_check(Z,L) interface checks to see whether or not 7648 ** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero 7649 ** if it is and zero if not. 7650 ** 7651 ** The parser used by SQLite is forgiving. It is often possible to use 7652 ** a keyword as an identifier as long as such use does not result in a 7653 ** parsing ambiguity. For example, the statement 7654 ** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and 7655 ** creates a new table named "BEGIN" with three columns named 7656 ** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid 7657 ** using keywords as identifiers. Common techniques used to avoid keyword 7658 ** name collisions include: 7659 ** <ul> 7660 ** <li> Put all identifier names inside double-quotes. This is the official 7661 ** SQL way to escape identifier names. 7662 ** <li> Put identifier names inside [...]. This is not standard SQL, 7663 ** but it is what SQL Server does and so lots of programmers use this 7664 ** technique. 7665 ** <li> Begin every identifier with the letter "Z" as no SQL keywords start 7666 ** with "Z". 7667 ** <li> Include a digit somewhere in every identifier name. 7668 ** </ul> 7669 ** 7670 ** Note that the number of keywords understood by SQLite can depend on 7671 ** compile-time options. For example, "VACUUM" is not a keyword if 7672 ** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also, 7673 ** new keywords may be added to future releases of SQLite. 7674 */ 7675 SQLITE_API int sqlite3_keyword_count(void); 7676 SQLITE_API int sqlite3_keyword_name(int,const char**,int*); 7677 SQLITE_API int sqlite3_keyword_check(const char*,int); 7678 7679 /* 7680 ** CAPI3REF: Dynamic String Object 7681 ** KEYWORDS: {dynamic string} 7682 ** 7683 ** An instance of the sqlite3_str object contains a dynamically-sized 7684 ** string under construction. 7685 ** 7686 ** The lifecycle of an sqlite3_str object is as follows: 7687 ** <ol> 7688 ** <li> ^The sqlite3_str object is created using [sqlite3_str_new()]. 7689 ** <li> ^Text is appended to the sqlite3_str object using various 7690 ** methods, such as [sqlite3_str_appendf()]. 7691 ** <li> ^The sqlite3_str object is destroyed and the string it created 7692 ** is returned using the [sqlite3_str_finish()] interface. 7693 ** </ol> 7694 */ 7695 typedef struct sqlite3_str sqlite3_str; 7696 7697 /* 7698 ** CAPI3REF: Create A New Dynamic String Object 7699 ** CONSTRUCTOR: sqlite3_str 7700 ** 7701 ** ^The [sqlite3_str_new(D)] interface allocates and initializes 7702 ** a new [sqlite3_str] object. To avoid memory leaks, the object returned by 7703 ** [sqlite3_str_new()] must be freed by a subsequent call to 7704 ** [sqlite3_str_finish(X)]. 7705 ** 7706 ** ^The [sqlite3_str_new(D)] interface always returns a pointer to a 7707 ** valid [sqlite3_str] object, though in the event of an out-of-memory 7708 ** error the returned object might be a special singleton that will 7709 ** silently reject new text, always return SQLITE_NOMEM from 7710 ** [sqlite3_str_errcode()], always return 0 for 7711 ** [sqlite3_str_length()], and always return NULL from 7712 ** [sqlite3_str_finish(X)]. It is always safe to use the value 7713 ** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter 7714 ** to any of the other [sqlite3_str] methods. 7715 ** 7716 ** The D parameter to [sqlite3_str_new(D)] may be NULL. If the 7717 ** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum 7718 ** length of the string contained in the [sqlite3_str] object will be 7719 ** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead 7720 ** of [SQLITE_MAX_LENGTH]. 7721 */ 7722 SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*); 7723 7724 /* 7725 ** CAPI3REF: Finalize A Dynamic String 7726 ** DESTRUCTOR: sqlite3_str 7727 ** 7728 ** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X 7729 ** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()] 7730 ** that contains the constructed string. The calling application should 7731 ** pass the returned value to [sqlite3_free()] to avoid a memory leak. 7732 ** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any 7733 ** errors were encountered during construction of the string. ^The 7734 ** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the 7735 ** string in [sqlite3_str] object X is zero bytes long. 7736 */ 7737 SQLITE_API char *sqlite3_str_finish(sqlite3_str*); 7738 7739 /* 7740 ** CAPI3REF: Add Content To A Dynamic String 7741 ** METHOD: sqlite3_str 7742 ** 7743 ** These interfaces add content to an sqlite3_str object previously obtained 7744 ** from [sqlite3_str_new()]. 7745 ** 7746 ** ^The [sqlite3_str_appendf(X,F,...)] and 7747 ** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf] 7748 ** functionality of SQLite to append formatted text onto the end of 7749 ** [sqlite3_str] object X. 7750 ** 7751 ** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S 7752 ** onto the end of the [sqlite3_str] object X. N must be non-negative. 7753 ** S must contain at least N non-zero bytes of content. To append a 7754 ** zero-terminated string in its entirety, use the [sqlite3_str_appendall()] 7755 ** method instead. 7756 ** 7757 ** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of 7758 ** zero-terminated string S onto the end of [sqlite3_str] object X. 7759 ** 7760 ** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the 7761 ** single-byte character C onto the end of [sqlite3_str] object X. 7762 ** ^This method can be used, for example, to add whitespace indentation. 7763 ** 7764 ** ^The [sqlite3_str_reset(X)] method resets the string under construction 7765 ** inside [sqlite3_str] object X back to zero bytes in length. 7766 ** 7767 ** These methods do not return a result code. ^If an error occurs, that fact 7768 ** is recorded in the [sqlite3_str] object and can be recovered by a 7769 ** subsequent call to [sqlite3_str_errcode(X)]. 7770 */ 7771 SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...); 7772 SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list); 7773 SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N); 7774 SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn); 7775 SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C); 7776 SQLITE_API void sqlite3_str_reset(sqlite3_str*); 7777 7778 /* 7779 ** CAPI3REF: Status Of A Dynamic String 7780 ** METHOD: sqlite3_str 7781 ** 7782 ** These interfaces return the current status of an [sqlite3_str] object. 7783 ** 7784 ** ^If any prior errors have occurred while constructing the dynamic string 7785 ** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return 7786 ** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns 7787 ** [SQLITE_NOMEM] following any out-of-memory error, or 7788 ** [SQLITE_TOOBIG] if the size of the dynamic string exceeds 7789 ** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors. 7790 ** 7791 ** ^The [sqlite3_str_length(X)] method returns the current length, in bytes, 7792 ** of the dynamic string under construction in [sqlite3_str] object X. 7793 ** ^The length returned by [sqlite3_str_length(X)] does not include the 7794 ** zero-termination byte. 7795 ** 7796 ** ^The [sqlite3_str_value(X)] method returns a pointer to the current 7797 ** content of the dynamic string under construction in X. The value 7798 ** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X 7799 ** and might be freed or altered by any subsequent method on the same 7800 ** [sqlite3_str] object. Applications must not used the pointer returned 7801 ** [sqlite3_str_value(X)] after any subsequent method call on the same 7802 ** object. ^Applications may change the content of the string returned 7803 ** by [sqlite3_str_value(X)] as long as they do not write into any bytes 7804 ** outside the range of 0 to [sqlite3_str_length(X)] and do not read or 7805 ** write any byte after any subsequent sqlite3_str method call. 7806 */ 7807 SQLITE_API int sqlite3_str_errcode(sqlite3_str*); 7808 SQLITE_API int sqlite3_str_length(sqlite3_str*); 7809 SQLITE_API char *sqlite3_str_value(sqlite3_str*); 7810 7811 /* 7812 ** CAPI3REF: SQLite Runtime Status 7813 ** 7814 ** ^These interfaces are used to retrieve runtime status information 7815 ** about the performance of SQLite, and optionally to reset various 7816 ** highwater marks. ^The first argument is an integer code for 7817 ** the specific parameter to measure. ^(Recognized integer codes 7818 ** are of the form [status parameters | SQLITE_STATUS_...].)^ 7819 ** ^The current value of the parameter is returned into *pCurrent. 7820 ** ^The highest recorded value is returned in *pHighwater. ^If the 7821 ** resetFlag is true, then the highest record value is reset after 7822 ** *pHighwater is written. ^(Some parameters do not record the highest 7823 ** value. For those parameters 7824 ** nothing is written into *pHighwater and the resetFlag is ignored.)^ 7825 ** ^(Other parameters record only the highwater mark and not the current 7826 ** value. For these latter parameters nothing is written into *pCurrent.)^ 7827 ** 7828 ** ^The sqlite3_status() and sqlite3_status64() routines return 7829 ** SQLITE_OK on success and a non-zero [error code] on failure. 7830 ** 7831 ** If either the current value or the highwater mark is too large to 7832 ** be represented by a 32-bit integer, then the values returned by 7833 ** sqlite3_status() are undefined. 7834 ** 7835 ** See also: [sqlite3_db_status()] 7836 */ 7837 SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); 7838 SQLITE_API int sqlite3_status64( 7839 int op, 7840 sqlite3_int64 *pCurrent, 7841 sqlite3_int64 *pHighwater, 7842 int resetFlag 7843 ); 7844 7845 7846 /* 7847 ** CAPI3REF: Status Parameters 7848 ** KEYWORDS: {status parameters} 7849 ** 7850 ** These integer constants designate various run-time status parameters 7851 ** that can be returned by [sqlite3_status()]. 7852 ** 7853 ** <dl> 7854 ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt> 7855 ** <dd>This parameter is the current amount of memory checked out 7856 ** using [sqlite3_malloc()], either directly or indirectly. The 7857 ** figure includes calls made to [sqlite3_malloc()] by the application 7858 ** and internal memory usage by the SQLite library. Auxiliary page-cache 7859 ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in 7860 ** this parameter. The amount returned is the sum of the allocation 7861 ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^ 7862 ** 7863 ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt> 7864 ** <dd>This parameter records the largest memory allocation request 7865 ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their 7866 ** internal equivalents). Only the value returned in the 7867 ** *pHighwater parameter to [sqlite3_status()] is of interest. 7868 ** The value written into the *pCurrent parameter is undefined.</dd>)^ 7869 ** 7870 ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt> 7871 ** <dd>This parameter records the number of separate memory allocations 7872 ** currently checked out.</dd>)^ 7873 ** 7874 ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt> 7875 ** <dd>This parameter returns the number of pages used out of the 7876 ** [pagecache memory allocator] that was configured using 7877 ** [SQLITE_CONFIG_PAGECACHE]. The 7878 ** value returned is in pages, not in bytes.</dd>)^ 7879 ** 7880 ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] 7881 ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> 7882 ** <dd>This parameter returns the number of bytes of page cache 7883 ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] 7884 ** buffer and where forced to overflow to [sqlite3_malloc()]. The 7885 ** returned value includes allocations that overflowed because they 7886 ** where too large (they were larger than the "sz" parameter to 7887 ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because 7888 ** no space was left in the page cache.</dd>)^ 7889 ** 7890 ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> 7891 ** <dd>This parameter records the largest memory allocation request 7892 ** handed to the [pagecache memory allocator]. Only the value returned in the 7893 ** *pHighwater parameter to [sqlite3_status()] is of interest. 7894 ** The value written into the *pCurrent parameter is undefined.</dd>)^ 7895 ** 7896 ** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt> 7897 ** <dd>No longer used.</dd> 7898 ** 7899 ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> 7900 ** <dd>No longer used.</dd> 7901 ** 7902 ** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt> 7903 ** <dd>No longer used.</dd> 7904 ** 7905 ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt> 7906 ** <dd>The *pHighwater parameter records the deepest parser stack. 7907 ** The *pCurrent value is undefined. The *pHighwater value is only 7908 ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^ 7909 ** </dl> 7910 ** 7911 ** New status parameters may be added from time to time. 7912 */ 7913 #define SQLITE_STATUS_MEMORY_USED 0 7914 #define SQLITE_STATUS_PAGECACHE_USED 1 7915 #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 7916 #define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */ 7917 #define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */ 7918 #define SQLITE_STATUS_MALLOC_SIZE 5 7919 #define SQLITE_STATUS_PARSER_STACK 6 7920 #define SQLITE_STATUS_PAGECACHE_SIZE 7 7921 #define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */ 7922 #define SQLITE_STATUS_MALLOC_COUNT 9 7923 7924 /* 7925 ** CAPI3REF: Database Connection Status 7926 ** METHOD: sqlite3 7927 ** 7928 ** ^This interface is used to retrieve runtime status information 7929 ** about a single [database connection]. ^The first argument is the 7930 ** database connection object to be interrogated. ^The second argument 7931 ** is an integer constant, taken from the set of 7932 ** [SQLITE_DBSTATUS options], that 7933 ** determines the parameter to interrogate. The set of 7934 ** [SQLITE_DBSTATUS options] is likely 7935 ** to grow in future releases of SQLite. 7936 ** 7937 ** ^The current value of the requested parameter is written into *pCur 7938 ** and the highest instantaneous value is written into *pHiwtr. ^If 7939 ** the resetFlg is true, then the highest instantaneous value is 7940 ** reset back down to the current value. 7941 ** 7942 ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a 7943 ** non-zero [error code] on failure. 7944 ** 7945 ** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. 7946 */ 7947 SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); 7948 7949 /* 7950 ** CAPI3REF: Status Parameters for database connections 7951 ** KEYWORDS: {SQLITE_DBSTATUS options} 7952 ** 7953 ** These constants are the available integer "verbs" that can be passed as 7954 ** the second argument to the [sqlite3_db_status()] interface. 7955 ** 7956 ** New verbs may be added in future releases of SQLite. Existing verbs 7957 ** might be discontinued. Applications should check the return code from 7958 ** [sqlite3_db_status()] to make sure that the call worked. 7959 ** The [sqlite3_db_status()] interface will return a non-zero error code 7960 ** if a discontinued or unsupported verb is invoked. 7961 ** 7962 ** <dl> 7963 ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> 7964 ** <dd>This parameter returns the number of lookaside memory slots currently 7965 ** checked out.</dd>)^ 7966 ** 7967 ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt> 7968 ** <dd>This parameter returns the number of malloc attempts that were 7969 ** satisfied using lookaside memory. Only the high-water value is meaningful; 7970 ** the current value is always zero.)^ 7971 ** 7972 ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] 7973 ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt> 7974 ** <dd>This parameter returns the number malloc attempts that might have 7975 ** been satisfied using lookaside memory but failed due to the amount of 7976 ** memory requested being larger than the lookaside slot size. 7977 ** Only the high-water value is meaningful; 7978 ** the current value is always zero.)^ 7979 ** 7980 ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] 7981 ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt> 7982 ** <dd>This parameter returns the number malloc attempts that might have 7983 ** been satisfied using lookaside memory but failed due to all lookaside 7984 ** memory already being in use. 7985 ** Only the high-water value is meaningful; 7986 ** the current value is always zero.)^ 7987 ** 7988 ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt> 7989 ** <dd>This parameter returns the approximate number of bytes of heap 7990 ** memory used by all pager caches associated with the database connection.)^ 7991 ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. 7992 ** 7993 ** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] 7994 ** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt> 7995 ** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a 7996 ** pager cache is shared between two or more connections the bytes of heap 7997 ** memory used by that pager cache is divided evenly between the attached 7998 ** connections.)^ In other words, if none of the pager caches associated 7999 ** with the database connection are shared, this request returns the same 8000 ** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are 8001 ** shared, the value returned by this call will be smaller than that returned 8002 ** by DBSTATUS_CACHE_USED. ^The highwater mark associated with 8003 ** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0. 8004 ** 8005 ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt> 8006 ** <dd>This parameter returns the approximate number of bytes of heap 8007 ** memory used to store the schema for all databases associated 8008 ** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 8009 ** ^The full amount of memory used by the schemas is reported, even if the 8010 ** schema memory is shared with other database connections due to 8011 ** [shared cache mode] being enabled. 8012 ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. 8013 ** 8014 ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt> 8015 ** <dd>This parameter returns the approximate number of bytes of heap 8016 ** and lookaside memory used by all prepared statements associated with 8017 ** the database connection.)^ 8018 ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. 8019 ** </dd> 8020 ** 8021 ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt> 8022 ** <dd>This parameter returns the number of pager cache hits that have 8023 ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT 8024 ** is always 0. 8025 ** </dd> 8026 ** 8027 ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt> 8028 ** <dd>This parameter returns the number of pager cache misses that have 8029 ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS 8030 ** is always 0. 8031 ** </dd> 8032 ** 8033 ** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt> 8034 ** <dd>This parameter returns the number of dirty cache entries that have 8035 ** been written to disk. Specifically, the number of pages written to the 8036 ** wal file in wal mode databases, or the number of pages written to the 8037 ** database file in rollback mode databases. Any pages written as part of 8038 ** transaction rollback or database recovery operations are not included. 8039 ** If an IO or other error occurs while writing a page to disk, the effect 8040 ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The 8041 ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. 8042 ** </dd> 8043 ** 8044 ** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt> 8045 ** <dd>This parameter returns the number of dirty cache entries that have 8046 ** been written to disk in the middle of a transaction due to the page 8047 ** cache overflowing. Transactions are more efficient if they are written 8048 ** to disk all at once. When pages spill mid-transaction, that introduces 8049 ** additional overhead. This parameter can be used help identify 8050 ** inefficiencies that can be resolved by increasing the cache size. 8051 ** </dd> 8052 ** 8053 ** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt> 8054 ** <dd>This parameter returns zero for the current value if and only if 8055 ** all foreign key constraints (deferred or immediate) have been 8056 ** resolved.)^ ^The highwater mark is always 0. 8057 ** </dd> 8058 ** </dl> 8059 */ 8060 #define SQLITE_DBSTATUS_LOOKASIDE_USED 0 8061 #define SQLITE_DBSTATUS_CACHE_USED 1 8062 #define SQLITE_DBSTATUS_SCHEMA_USED 2 8063 #define SQLITE_DBSTATUS_STMT_USED 3 8064 #define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 8065 #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 8066 #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 8067 #define SQLITE_DBSTATUS_CACHE_HIT 7 8068 #define SQLITE_DBSTATUS_CACHE_MISS 8 8069 #define SQLITE_DBSTATUS_CACHE_WRITE 9 8070 #define SQLITE_DBSTATUS_DEFERRED_FKS 10 8071 #define SQLITE_DBSTATUS_CACHE_USED_SHARED 11 8072 #define SQLITE_DBSTATUS_CACHE_SPILL 12 8073 #define SQLITE_DBSTATUS_MAX 12 /* Largest defined DBSTATUS */ 8074 8075 8076 /* 8077 ** CAPI3REF: Prepared Statement Status 8078 ** METHOD: sqlite3_stmt 8079 ** 8080 ** ^(Each prepared statement maintains various 8081 ** [SQLITE_STMTSTATUS counters] that measure the number 8082 ** of times it has performed specific operations.)^ These counters can 8083 ** be used to monitor the performance characteristics of the prepared 8084 ** statements. For example, if the number of table steps greatly exceeds 8085 ** the number of table searches or result rows, that would tend to indicate 8086 ** that the prepared statement is using a full table scan rather than 8087 ** an index. 8088 ** 8089 ** ^(This interface is used to retrieve and reset counter values from 8090 ** a [prepared statement]. The first argument is the prepared statement 8091 ** object to be interrogated. The second argument 8092 ** is an integer code for a specific [SQLITE_STMTSTATUS counter] 8093 ** to be interrogated.)^ 8094 ** ^The current value of the requested counter is returned. 8095 ** ^If the resetFlg is true, then the counter is reset to zero after this 8096 ** interface call returns. 8097 ** 8098 ** See also: [sqlite3_status()] and [sqlite3_db_status()]. 8099 */ 8100 SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); 8101 8102 /* 8103 ** CAPI3REF: Status Parameters for prepared statements 8104 ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} 8105 ** 8106 ** These preprocessor macros define integer codes that name counter 8107 ** values associated with the [sqlite3_stmt_status()] interface. 8108 ** The meanings of the various counters are as follows: 8109 ** 8110 ** <dl> 8111 ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt> 8112 ** <dd>^This is the number of times that SQLite has stepped forward in 8113 ** a table as part of a full table scan. Large numbers for this counter 8114 ** may indicate opportunities for performance improvement through 8115 ** careful use of indices.</dd> 8116 ** 8117 ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt> 8118 ** <dd>^This is the number of sort operations that have occurred. 8119 ** A non-zero value in this counter may indicate an opportunity to 8120 ** improvement performance through careful use of indices.</dd> 8121 ** 8122 ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt> 8123 ** <dd>^This is the number of rows inserted into transient indices that 8124 ** were created automatically in order to help joins run faster. 8125 ** A non-zero value in this counter may indicate an opportunity to 8126 ** improvement performance by adding permanent indices that do not 8127 ** need to be reinitialized each time the statement is run.</dd> 8128 ** 8129 ** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt> 8130 ** <dd>^This is the number of virtual machine operations executed 8131 ** by the prepared statement if that number is less than or equal 8132 ** to 2147483647. The number of virtual machine operations can be 8133 ** used as a proxy for the total work done by the prepared statement. 8134 ** If the number of virtual machine operations exceeds 2147483647 8135 ** then the value returned by this statement status code is undefined. 8136 ** 8137 ** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt> 8138 ** <dd>^This is the number of times that the prepare statement has been 8139 ** automatically regenerated due to schema changes or changes to 8140 ** [bound parameters] that might affect the query plan. 8141 ** 8142 ** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt> 8143 ** <dd>^This is the number of times that the prepared statement has 8144 ** been run. A single "run" for the purposes of this counter is one 8145 ** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()]. 8146 ** The counter is incremented on the first [sqlite3_step()] call of each 8147 ** cycle. 8148 ** 8149 ** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt> 8150 ** <dd>^This is the approximate number of bytes of heap memory 8151 ** used to store the prepared statement. ^This value is not actually 8152 ** a counter, and so the resetFlg parameter to sqlite3_stmt_status() 8153 ** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED. 8154 ** </dd> 8155 ** </dl> 8156 */ 8157 #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 8158 #define SQLITE_STMTSTATUS_SORT 2 8159 #define SQLITE_STMTSTATUS_AUTOINDEX 3 8160 #define SQLITE_STMTSTATUS_VM_STEP 4 8161 #define SQLITE_STMTSTATUS_REPREPARE 5 8162 #define SQLITE_STMTSTATUS_RUN 6 8163 #define SQLITE_STMTSTATUS_MEMUSED 99 8164 8165 /* 8166 ** CAPI3REF: Custom Page Cache Object 8167 ** 8168 ** The sqlite3_pcache type is opaque. It is implemented by 8169 ** the pluggable module. The SQLite core has no knowledge of 8170 ** its size or internal structure and never deals with the 8171 ** sqlite3_pcache object except by holding and passing pointers 8172 ** to the object. 8173 ** 8174 ** See [sqlite3_pcache_methods2] for additional information. 8175 */ 8176 typedef struct sqlite3_pcache sqlite3_pcache; 8177 8178 /* 8179 ** CAPI3REF: Custom Page Cache Object 8180 ** 8181 ** The sqlite3_pcache_page object represents a single page in the 8182 ** page cache. The page cache will allocate instances of this 8183 ** object. Various methods of the page cache use pointers to instances 8184 ** of this object as parameters or as their return value. 8185 ** 8186 ** See [sqlite3_pcache_methods2] for additional information. 8187 */ 8188 typedef struct sqlite3_pcache_page sqlite3_pcache_page; 8189 struct sqlite3_pcache_page { 8190 void *pBuf; /* The content of the page */ 8191 void *pExtra; /* Extra information associated with the page */ 8192 }; 8193 8194 /* 8195 ** CAPI3REF: Application Defined Page Cache. 8196 ** KEYWORDS: {page cache} 8197 ** 8198 ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can 8199 ** register an alternative page cache implementation by passing in an 8200 ** instance of the sqlite3_pcache_methods2 structure.)^ 8201 ** In many applications, most of the heap memory allocated by 8202 ** SQLite is used for the page cache. 8203 ** By implementing a 8204 ** custom page cache using this API, an application can better control 8205 ** the amount of memory consumed by SQLite, the way in which 8206 ** that memory is allocated and released, and the policies used to 8207 ** determine exactly which parts of a database file are cached and for 8208 ** how long. 8209 ** 8210 ** The alternative page cache mechanism is an 8211 ** extreme measure that is only needed by the most demanding applications. 8212 ** The built-in page cache is recommended for most uses. 8213 ** 8214 ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an 8215 ** internal buffer by SQLite within the call to [sqlite3_config]. Hence 8216 ** the application may discard the parameter after the call to 8217 ** [sqlite3_config()] returns.)^ 8218 ** 8219 ** [[the xInit() page cache method]] 8220 ** ^(The xInit() method is called once for each effective 8221 ** call to [sqlite3_initialize()])^ 8222 ** (usually only once during the lifetime of the process). ^(The xInit() 8223 ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ 8224 ** The intent of the xInit() method is to set up global data structures 8225 ** required by the custom page cache implementation. 8226 ** ^(If the xInit() method is NULL, then the 8227 ** built-in default page cache is used instead of the application defined 8228 ** page cache.)^ 8229 ** 8230 ** [[the xShutdown() page cache method]] 8231 ** ^The xShutdown() method is called by [sqlite3_shutdown()]. 8232 ** It can be used to clean up 8233 ** any outstanding resources before process shutdown, if required. 8234 ** ^The xShutdown() method may be NULL. 8235 ** 8236 ** ^SQLite automatically serializes calls to the xInit method, 8237 ** so the xInit method need not be threadsafe. ^The 8238 ** xShutdown method is only called from [sqlite3_shutdown()] so it does 8239 ** not need to be threadsafe either. All other methods must be threadsafe 8240 ** in multithreaded applications. 8241 ** 8242 ** ^SQLite will never invoke xInit() more than once without an intervening 8243 ** call to xShutdown(). 8244 ** 8245 ** [[the xCreate() page cache methods]] 8246 ** ^SQLite invokes the xCreate() method to construct a new cache instance. 8247 ** SQLite will typically create one cache instance for each open database file, 8248 ** though this is not guaranteed. ^The 8249 ** first parameter, szPage, is the size in bytes of the pages that must 8250 ** be allocated by the cache. ^szPage will always a power of two. ^The 8251 ** second parameter szExtra is a number of bytes of extra storage 8252 ** associated with each page cache entry. ^The szExtra parameter will 8253 ** a number less than 250. SQLite will use the 8254 ** extra szExtra bytes on each page to store metadata about the underlying 8255 ** database page on disk. The value passed into szExtra depends 8256 ** on the SQLite version, the target platform, and how SQLite was compiled. 8257 ** ^The third argument to xCreate(), bPurgeable, is true if the cache being 8258 ** created will be used to cache database pages of a file stored on disk, or 8259 ** false if it is used for an in-memory database. The cache implementation 8260 ** does not have to do anything special based with the value of bPurgeable; 8261 ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will 8262 ** never invoke xUnpin() except to deliberately delete a page. 8263 ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to 8264 ** false will always have the "discard" flag set to true. 8265 ** ^Hence, a cache created with bPurgeable false will 8266 ** never contain any unpinned pages. 8267 ** 8268 ** [[the xCachesize() page cache method]] 8269 ** ^(The xCachesize() method may be called at any time by SQLite to set the 8270 ** suggested maximum cache-size (number of pages stored by) the cache 8271 ** instance passed as the first argument. This is the value configured using 8272 ** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable 8273 ** parameter, the implementation is not required to do anything with this 8274 ** value; it is advisory only. 8275 ** 8276 ** [[the xPagecount() page cache methods]] 8277 ** The xPagecount() method must return the number of pages currently 8278 ** stored in the cache, both pinned and unpinned. 8279 ** 8280 ** [[the xFetch() page cache methods]] 8281 ** The xFetch() method locates a page in the cache and returns a pointer to 8282 ** an sqlite3_pcache_page object associated with that page, or a NULL pointer. 8283 ** The pBuf element of the returned sqlite3_pcache_page object will be a 8284 ** pointer to a buffer of szPage bytes used to store the content of a 8285 ** single database page. The pExtra element of sqlite3_pcache_page will be 8286 ** a pointer to the szExtra bytes of extra storage that SQLite has requested 8287 ** for each entry in the page cache. 8288 ** 8289 ** The page to be fetched is determined by the key. ^The minimum key value 8290 ** is 1. After it has been retrieved using xFetch, the page is considered 8291 ** to be "pinned". 8292 ** 8293 ** If the requested page is already in the page cache, then the page cache 8294 ** implementation must return a pointer to the page buffer with its content 8295 ** intact. If the requested page is not already in the cache, then the 8296 ** cache implementation should use the value of the createFlag 8297 ** parameter to help it determined what action to take: 8298 ** 8299 ** <table border=1 width=85% align=center> 8300 ** <tr><th> createFlag <th> Behavior when page is not already in cache 8301 ** <tr><td> 0 <td> Do not allocate a new page. Return NULL. 8302 ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so. 8303 ** Otherwise return NULL. 8304 ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return 8305 ** NULL if allocating a new page is effectively impossible. 8306 ** </table> 8307 ** 8308 ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite 8309 ** will only use a createFlag of 2 after a prior call with a createFlag of 1 8310 ** failed.)^ In between the xFetch() calls, SQLite may 8311 ** attempt to unpin one or more cache pages by spilling the content of 8312 ** pinned pages to disk and synching the operating system disk cache. 8313 ** 8314 ** [[the xUnpin() page cache method]] 8315 ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page 8316 ** as its second argument. If the third parameter, discard, is non-zero, 8317 ** then the page must be evicted from the cache. 8318 ** ^If the discard parameter is 8319 ** zero, then the page may be discarded or retained at the discretion of 8320 ** page cache implementation. ^The page cache implementation 8321 ** may choose to evict unpinned pages at any time. 8322 ** 8323 ** The cache must not perform any reference counting. A single 8324 ** call to xUnpin() unpins the page regardless of the number of prior calls 8325 ** to xFetch(). 8326 ** 8327 ** [[the xRekey() page cache methods]] 8328 ** The xRekey() method is used to change the key value associated with the 8329 ** page passed as the second argument. If the cache 8330 ** previously contains an entry associated with newKey, it must be 8331 ** discarded. ^Any prior cache entry associated with newKey is guaranteed not 8332 ** to be pinned. 8333 ** 8334 ** When SQLite calls the xTruncate() method, the cache must discard all 8335 ** existing cache entries with page numbers (keys) greater than or equal 8336 ** to the value of the iLimit parameter passed to xTruncate(). If any 8337 ** of these pages are pinned, they are implicitly unpinned, meaning that 8338 ** they can be safely discarded. 8339 ** 8340 ** [[the xDestroy() page cache method]] 8341 ** ^The xDestroy() method is used to delete a cache allocated by xCreate(). 8342 ** All resources associated with the specified cache should be freed. ^After 8343 ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] 8344 ** handle invalid, and will not use it with any other sqlite3_pcache_methods2 8345 ** functions. 8346 ** 8347 ** [[the xShrink() page cache method]] 8348 ** ^SQLite invokes the xShrink() method when it wants the page cache to 8349 ** free up as much of heap memory as possible. The page cache implementation 8350 ** is not obligated to free any memory, but well-behaved implementations should 8351 ** do their best. 8352 */ 8353 typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; 8354 struct sqlite3_pcache_methods2 { 8355 int iVersion; 8356 void *pArg; 8357 int (*xInit)(void*); 8358 void (*xShutdown)(void*); 8359 sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable); 8360 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 8361 int (*xPagecount)(sqlite3_pcache*); 8362 sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 8363 void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); 8364 void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, 8365 unsigned oldKey, unsigned newKey); 8366 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 8367 void (*xDestroy)(sqlite3_pcache*); 8368 void (*xShrink)(sqlite3_pcache*); 8369 }; 8370 8371 /* 8372 ** This is the obsolete pcache_methods object that has now been replaced 8373 ** by sqlite3_pcache_methods2. This object is not used by SQLite. It is 8374 ** retained in the header file for backwards compatibility only. 8375 */ 8376 typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; 8377 struct sqlite3_pcache_methods { 8378 void *pArg; 8379 int (*xInit)(void*); 8380 void (*xShutdown)(void*); 8381 sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); 8382 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 8383 int (*xPagecount)(sqlite3_pcache*); 8384 void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 8385 void (*xUnpin)(sqlite3_pcache*, void*, int discard); 8386 void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); 8387 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 8388 void (*xDestroy)(sqlite3_pcache*); 8389 }; 8390 8391 8392 /* 8393 ** CAPI3REF: Online Backup Object 8394 ** 8395 ** The sqlite3_backup object records state information about an ongoing 8396 ** online backup operation. ^The sqlite3_backup object is created by 8397 ** a call to [sqlite3_backup_init()] and is destroyed by a call to 8398 ** [sqlite3_backup_finish()]. 8399 ** 8400 ** See Also: [Using the SQLite Online Backup API] 8401 */ 8402 typedef struct sqlite3_backup sqlite3_backup; 8403 8404 /* 8405 ** CAPI3REF: Online Backup API. 8406 ** 8407 ** The backup API copies the content of one database into another. 8408 ** It is useful either for creating backups of databases or 8409 ** for copying in-memory databases to or from persistent files. 8410 ** 8411 ** See Also: [Using the SQLite Online Backup API] 8412 ** 8413 ** ^SQLite holds a write transaction open on the destination database file 8414 ** for the duration of the backup operation. 8415 ** ^The source database is read-locked only while it is being read; 8416 ** it is not locked continuously for the entire backup operation. 8417 ** ^Thus, the backup may be performed on a live source database without 8418 ** preventing other database connections from 8419 ** reading or writing to the source database while the backup is underway. 8420 ** 8421 ** ^(To perform a backup operation: 8422 ** <ol> 8423 ** <li><b>sqlite3_backup_init()</b> is called once to initialize the 8424 ** backup, 8425 ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer 8426 ** the data between the two databases, and finally 8427 ** <li><b>sqlite3_backup_finish()</b> is called to release all resources 8428 ** associated with the backup operation. 8429 ** </ol>)^ 8430 ** There should be exactly one call to sqlite3_backup_finish() for each 8431 ** successful call to sqlite3_backup_init(). 8432 ** 8433 ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b> 8434 ** 8435 ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the 8436 ** [database connection] associated with the destination database 8437 ** and the database name, respectively. 8438 ** ^The database name is "main" for the main database, "temp" for the 8439 ** temporary database, or the name specified after the AS keyword in 8440 ** an [ATTACH] statement for an attached database. 8441 ** ^The S and M arguments passed to 8442 ** sqlite3_backup_init(D,N,S,M) identify the [database connection] 8443 ** and database name of the source database, respectively. 8444 ** ^The source and destination [database connections] (parameters S and D) 8445 ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with 8446 ** an error. 8447 ** 8448 ** ^A call to sqlite3_backup_init() will fail, returning NULL, if 8449 ** there is already a read or read-write transaction open on the 8450 ** destination database. 8451 ** 8452 ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is 8453 ** returned and an error code and error message are stored in the 8454 ** destination [database connection] D. 8455 ** ^The error code and message for the failed call to sqlite3_backup_init() 8456 ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or 8457 ** [sqlite3_errmsg16()] functions. 8458 ** ^A successful call to sqlite3_backup_init() returns a pointer to an 8459 ** [sqlite3_backup] object. 8460 ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and 8461 ** sqlite3_backup_finish() functions to perform the specified backup 8462 ** operation. 8463 ** 8464 ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b> 8465 ** 8466 ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between 8467 ** the source and destination databases specified by [sqlite3_backup] object B. 8468 ** ^If N is negative, all remaining source pages are copied. 8469 ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there 8470 ** are still more pages to be copied, then the function returns [SQLITE_OK]. 8471 ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages 8472 ** from source to destination, then it returns [SQLITE_DONE]. 8473 ** ^If an error occurs while running sqlite3_backup_step(B,N), 8474 ** then an [error code] is returned. ^As well as [SQLITE_OK] and 8475 ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], 8476 ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an 8477 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. 8478 ** 8479 ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if 8480 ** <ol> 8481 ** <li> the destination database was opened read-only, or 8482 ** <li> the destination database is using write-ahead-log journaling 8483 ** and the destination and source page sizes differ, or 8484 ** <li> the destination database is an in-memory database and the 8485 ** destination and source page sizes differ. 8486 ** </ol>)^ 8487 ** 8488 ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then 8489 ** the [sqlite3_busy_handler | busy-handler function] 8490 ** is invoked (if one is specified). ^If the 8491 ** busy-handler returns non-zero before the lock is available, then 8492 ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to 8493 ** sqlite3_backup_step() can be retried later. ^If the source 8494 ** [database connection] 8495 ** is being used to write to the source database when sqlite3_backup_step() 8496 ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this 8497 ** case the call to sqlite3_backup_step() can be retried later on. ^(If 8498 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or 8499 ** [SQLITE_READONLY] is returned, then 8500 ** there is no point in retrying the call to sqlite3_backup_step(). These 8501 ** errors are considered fatal.)^ The application must accept 8502 ** that the backup operation has failed and pass the backup operation handle 8503 ** to the sqlite3_backup_finish() to release associated resources. 8504 ** 8505 ** ^The first call to sqlite3_backup_step() obtains an exclusive lock 8506 ** on the destination file. ^The exclusive lock is not released until either 8507 ** sqlite3_backup_finish() is called or the backup operation is complete 8508 ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to 8509 ** sqlite3_backup_step() obtains a [shared lock] on the source database that 8510 ** lasts for the duration of the sqlite3_backup_step() call. 8511 ** ^Because the source database is not locked between calls to 8512 ** sqlite3_backup_step(), the source database may be modified mid-way 8513 ** through the backup process. ^If the source database is modified by an 8514 ** external process or via a database connection other than the one being 8515 ** used by the backup operation, then the backup will be automatically 8516 ** restarted by the next call to sqlite3_backup_step(). ^If the source 8517 ** database is modified by the using the same database connection as is used 8518 ** by the backup operation, then the backup database is automatically 8519 ** updated at the same time. 8520 ** 8521 ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b> 8522 ** 8523 ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the 8524 ** application wishes to abandon the backup operation, the application 8525 ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). 8526 ** ^The sqlite3_backup_finish() interfaces releases all 8527 ** resources associated with the [sqlite3_backup] object. 8528 ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any 8529 ** active write-transaction on the destination database is rolled back. 8530 ** The [sqlite3_backup] object is invalid 8531 ** and may not be used following a call to sqlite3_backup_finish(). 8532 ** 8533 ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no 8534 ** sqlite3_backup_step() errors occurred, regardless or whether or not 8535 ** sqlite3_backup_step() completed. 8536 ** ^If an out-of-memory condition or IO error occurred during any prior 8537 ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then 8538 ** sqlite3_backup_finish() returns the corresponding [error code]. 8539 ** 8540 ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() 8541 ** is not a permanent error and does not affect the return value of 8542 ** sqlite3_backup_finish(). 8543 ** 8544 ** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]] 8545 ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b> 8546 ** 8547 ** ^The sqlite3_backup_remaining() routine returns the number of pages still 8548 ** to be backed up at the conclusion of the most recent sqlite3_backup_step(). 8549 ** ^The sqlite3_backup_pagecount() routine returns the total number of pages 8550 ** in the source database at the conclusion of the most recent 8551 ** sqlite3_backup_step(). 8552 ** ^(The values returned by these functions are only updated by 8553 ** sqlite3_backup_step(). If the source database is modified in a way that 8554 ** changes the size of the source database or the number of pages remaining, 8555 ** those changes are not reflected in the output of sqlite3_backup_pagecount() 8556 ** and sqlite3_backup_remaining() until after the next 8557 ** sqlite3_backup_step().)^ 8558 ** 8559 ** <b>Concurrent Usage of Database Handles</b> 8560 ** 8561 ** ^The source [database connection] may be used by the application for other 8562 ** purposes while a backup operation is underway or being initialized. 8563 ** ^If SQLite is compiled and configured to support threadsafe database 8564 ** connections, then the source database connection may be used concurrently 8565 ** from within other threads. 8566 ** 8567 ** However, the application must guarantee that the destination 8568 ** [database connection] is not passed to any other API (by any thread) after 8569 ** sqlite3_backup_init() is called and before the corresponding call to 8570 ** sqlite3_backup_finish(). SQLite does not currently check to see 8571 ** if the application incorrectly accesses the destination [database connection] 8572 ** and so no error code is reported, but the operations may malfunction 8573 ** nevertheless. Use of the destination database connection while a 8574 ** backup is in progress might also also cause a mutex deadlock. 8575 ** 8576 ** If running in [shared cache mode], the application must 8577 ** guarantee that the shared cache used by the destination database 8578 ** is not accessed while the backup is running. In practice this means 8579 ** that the application must guarantee that the disk file being 8580 ** backed up to is not accessed by any connection within the process, 8581 ** not just the specific connection that was passed to sqlite3_backup_init(). 8582 ** 8583 ** The [sqlite3_backup] object itself is partially threadsafe. Multiple 8584 ** threads may safely make multiple concurrent calls to sqlite3_backup_step(). 8585 ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() 8586 ** APIs are not strictly speaking threadsafe. If they are invoked at the 8587 ** same time as another thread is invoking sqlite3_backup_step() it is 8588 ** possible that they return invalid values. 8589 */ 8590 SQLITE_API sqlite3_backup *sqlite3_backup_init( 8591 sqlite3 *pDest, /* Destination database handle */ 8592 const char *zDestName, /* Destination database name */ 8593 sqlite3 *pSource, /* Source database handle */ 8594 const char *zSourceName /* Source database name */ 8595 ); 8596 SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage); 8597 SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p); 8598 SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p); 8599 SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p); 8600 8601 /* 8602 ** CAPI3REF: Unlock Notification 8603 ** METHOD: sqlite3 8604 ** 8605 ** ^When running in shared-cache mode, a database operation may fail with 8606 ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or 8607 ** individual tables within the shared-cache cannot be obtained. See 8608 ** [SQLite Shared-Cache Mode] for a description of shared-cache locking. 8609 ** ^This API may be used to register a callback that SQLite will invoke 8610 ** when the connection currently holding the required lock relinquishes it. 8611 ** ^This API is only available if the library was compiled with the 8612 ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. 8613 ** 8614 ** See Also: [Using the SQLite Unlock Notification Feature]. 8615 ** 8616 ** ^Shared-cache locks are released when a database connection concludes 8617 ** its current transaction, either by committing it or rolling it back. 8618 ** 8619 ** ^When a connection (known as the blocked connection) fails to obtain a 8620 ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the 8621 ** identity of the database connection (the blocking connection) that 8622 ** has locked the required resource is stored internally. ^After an 8623 ** application receives an SQLITE_LOCKED error, it may call the 8624 ** sqlite3_unlock_notify() method with the blocked connection handle as 8625 ** the first argument to register for a callback that will be invoked 8626 ** when the blocking connections current transaction is concluded. ^The 8627 ** callback is invoked from within the [sqlite3_step] or [sqlite3_close] 8628 ** call that concludes the blocking connection's transaction. 8629 ** 8630 ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, 8631 ** there is a chance that the blocking connection will have already 8632 ** concluded its transaction by the time sqlite3_unlock_notify() is invoked. 8633 ** If this happens, then the specified callback is invoked immediately, 8634 ** from within the call to sqlite3_unlock_notify().)^ 8635 ** 8636 ** ^If the blocked connection is attempting to obtain a write-lock on a 8637 ** shared-cache table, and more than one other connection currently holds 8638 ** a read-lock on the same table, then SQLite arbitrarily selects one of 8639 ** the other connections to use as the blocking connection. 8640 ** 8641 ** ^(There may be at most one unlock-notify callback registered by a 8642 ** blocked connection. If sqlite3_unlock_notify() is called when the 8643 ** blocked connection already has a registered unlock-notify callback, 8644 ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is 8645 ** called with a NULL pointer as its second argument, then any existing 8646 ** unlock-notify callback is canceled. ^The blocked connections 8647 ** unlock-notify callback may also be canceled by closing the blocked 8648 ** connection using [sqlite3_close()]. 8649 ** 8650 ** The unlock-notify callback is not reentrant. If an application invokes 8651 ** any sqlite3_xxx API functions from within an unlock-notify callback, a 8652 ** crash or deadlock may be the result. 8653 ** 8654 ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always 8655 ** returns SQLITE_OK. 8656 ** 8657 ** <b>Callback Invocation Details</b> 8658 ** 8659 ** When an unlock-notify callback is registered, the application provides a 8660 ** single void* pointer that is passed to the callback when it is invoked. 8661 ** However, the signature of the callback function allows SQLite to pass 8662 ** it an array of void* context pointers. The first argument passed to 8663 ** an unlock-notify callback is a pointer to an array of void* pointers, 8664 ** and the second is the number of entries in the array. 8665 ** 8666 ** When a blocking connection's transaction is concluded, there may be 8667 ** more than one blocked connection that has registered for an unlock-notify 8668 ** callback. ^If two or more such blocked connections have specified the 8669 ** same callback function, then instead of invoking the callback function 8670 ** multiple times, it is invoked once with the set of void* context pointers 8671 ** specified by the blocked connections bundled together into an array. 8672 ** This gives the application an opportunity to prioritize any actions 8673 ** related to the set of unblocked database connections. 8674 ** 8675 ** <b>Deadlock Detection</b> 8676 ** 8677 ** Assuming that after registering for an unlock-notify callback a 8678 ** database waits for the callback to be issued before taking any further 8679 ** action (a reasonable assumption), then using this API may cause the 8680 ** application to deadlock. For example, if connection X is waiting for 8681 ** connection Y's transaction to be concluded, and similarly connection 8682 ** Y is waiting on connection X's transaction, then neither connection 8683 ** will proceed and the system may remain deadlocked indefinitely. 8684 ** 8685 ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock 8686 ** detection. ^If a given call to sqlite3_unlock_notify() would put the 8687 ** system in a deadlocked state, then SQLITE_LOCKED is returned and no 8688 ** unlock-notify callback is registered. The system is said to be in 8689 ** a deadlocked state if connection A has registered for an unlock-notify 8690 ** callback on the conclusion of connection B's transaction, and connection 8691 ** B has itself registered for an unlock-notify callback when connection 8692 ** A's transaction is concluded. ^Indirect deadlock is also detected, so 8693 ** the system is also considered to be deadlocked if connection B has 8694 ** registered for an unlock-notify callback on the conclusion of connection 8695 ** C's transaction, where connection C is waiting on connection A. ^Any 8696 ** number of levels of indirection are allowed. 8697 ** 8698 ** <b>The "DROP TABLE" Exception</b> 8699 ** 8700 ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost 8701 ** always appropriate to call sqlite3_unlock_notify(). There is however, 8702 ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, 8703 ** SQLite checks if there are any currently executing SELECT statements 8704 ** that belong to the same connection. If there are, SQLITE_LOCKED is 8705 ** returned. In this case there is no "blocking connection", so invoking 8706 ** sqlite3_unlock_notify() results in the unlock-notify callback being 8707 ** invoked immediately. If the application then re-attempts the "DROP TABLE" 8708 ** or "DROP INDEX" query, an infinite loop might be the result. 8709 ** 8710 ** One way around this problem is to check the extended error code returned 8711 ** by an sqlite3_step() call. ^(If there is a blocking connection, then the 8712 ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in 8713 ** the special "DROP TABLE/INDEX" case, the extended error code is just 8714 ** SQLITE_LOCKED.)^ 8715 */ 8716 SQLITE_API int sqlite3_unlock_notify( 8717 sqlite3 *pBlocked, /* Waiting connection */ 8718 void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ 8719 void *pNotifyArg /* Argument to pass to xNotify */ 8720 ); 8721 8722 8723 /* 8724 ** CAPI3REF: String Comparison 8725 ** 8726 ** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications 8727 ** and extensions to compare the contents of two buffers containing UTF-8 8728 ** strings in a case-independent fashion, using the same definition of "case 8729 ** independence" that SQLite uses internally when comparing identifiers. 8730 */ 8731 SQLITE_API int sqlite3_stricmp(const char *, const char *); 8732 SQLITE_API int sqlite3_strnicmp(const char *, const char *, int); 8733 8734 /* 8735 ** CAPI3REF: String Globbing 8736 * 8737 ** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if 8738 ** string X matches the [GLOB] pattern P. 8739 ** ^The definition of [GLOB] pattern matching used in 8740 ** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the 8741 ** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function 8742 ** is case sensitive. 8743 ** 8744 ** Note that this routine returns zero on a match and non-zero if the strings 8745 ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 8746 ** 8747 ** See also: [sqlite3_strlike()]. 8748 */ 8749 SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr); 8750 8751 /* 8752 ** CAPI3REF: String LIKE Matching 8753 * 8754 ** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if 8755 ** string X matches the [LIKE] pattern P with escape character E. 8756 ** ^The definition of [LIKE] pattern matching used in 8757 ** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E" 8758 ** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without 8759 ** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0. 8760 ** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case 8761 ** insensitive - equivalent upper and lower case ASCII characters match 8762 ** one another. 8763 ** 8764 ** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though 8765 ** only ASCII characters are case folded. 8766 ** 8767 ** Note that this routine returns zero on a match and non-zero if the strings 8768 ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 8769 ** 8770 ** See also: [sqlite3_strglob()]. 8771 */ 8772 SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc); 8773 8774 /* 8775 ** CAPI3REF: Error Logging Interface 8776 ** 8777 ** ^The [sqlite3_log()] interface writes a message into the [error log] 8778 ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. 8779 ** ^If logging is enabled, the zFormat string and subsequent arguments are 8780 ** used with [sqlite3_snprintf()] to generate the final output string. 8781 ** 8782 ** The sqlite3_log() interface is intended for use by extensions such as 8783 ** virtual tables, collating functions, and SQL functions. While there is 8784 ** nothing to prevent an application from calling sqlite3_log(), doing so 8785 ** is considered bad form. 8786 ** 8787 ** The zFormat string must not be NULL. 8788 ** 8789 ** To avoid deadlocks and other threading problems, the sqlite3_log() routine 8790 ** will not use dynamically allocated memory. The log message is stored in 8791 ** a fixed-length buffer on the stack. If the log message is longer than 8792 ** a few hundred characters, it will be truncated to the length of the 8793 ** buffer. 8794 */ 8795 SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...); 8796 8797 /* 8798 ** CAPI3REF: Write-Ahead Log Commit Hook 8799 ** METHOD: sqlite3 8800 ** 8801 ** ^The [sqlite3_wal_hook()] function is used to register a callback that 8802 ** is invoked each time data is committed to a database in wal mode. 8803 ** 8804 ** ^(The callback is invoked by SQLite after the commit has taken place and 8805 ** the associated write-lock on the database released)^, so the implementation 8806 ** may read, write or [checkpoint] the database as required. 8807 ** 8808 ** ^The first parameter passed to the callback function when it is invoked 8809 ** is a copy of the third parameter passed to sqlite3_wal_hook() when 8810 ** registering the callback. ^The second is a copy of the database handle. 8811 ** ^The third parameter is the name of the database that was written to - 8812 ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter 8813 ** is the number of pages currently in the write-ahead log file, 8814 ** including those that were just committed. 8815 ** 8816 ** The callback function should normally return [SQLITE_OK]. ^If an error 8817 ** code is returned, that error will propagate back up through the 8818 ** SQLite code base to cause the statement that provoked the callback 8819 ** to report an error, though the commit will have still occurred. If the 8820 ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value 8821 ** that does not correspond to any valid SQLite error code, the results 8822 ** are undefined. 8823 ** 8824 ** A single database handle may have at most a single write-ahead log callback 8825 ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any 8826 ** previously registered write-ahead log callback. ^Note that the 8827 ** [sqlite3_wal_autocheckpoint()] interface and the 8828 ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will 8829 ** overwrite any prior [sqlite3_wal_hook()] settings. 8830 */ 8831 SQLITE_API void *sqlite3_wal_hook( 8832 sqlite3*, 8833 int(*)(void *,sqlite3*,const char*,int), 8834 void* 8835 ); 8836 8837 /* 8838 ** CAPI3REF: Configure an auto-checkpoint 8839 ** METHOD: sqlite3 8840 ** 8841 ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around 8842 ** [sqlite3_wal_hook()] that causes any database on [database connection] D 8843 ** to automatically [checkpoint] 8844 ** after committing a transaction if there are N or 8845 ** more frames in the [write-ahead log] file. ^Passing zero or 8846 ** a negative value as the nFrame parameter disables automatic 8847 ** checkpoints entirely. 8848 ** 8849 ** ^The callback registered by this function replaces any existing callback 8850 ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback 8851 ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism 8852 ** configured by this function. 8853 ** 8854 ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface 8855 ** from SQL. 8856 ** 8857 ** ^Checkpoints initiated by this mechanism are 8858 ** [sqlite3_wal_checkpoint_v2|PASSIVE]. 8859 ** 8860 ** ^Every new [database connection] defaults to having the auto-checkpoint 8861 ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] 8862 ** pages. The use of this interface 8863 ** is only necessary if the default setting is found to be suboptimal 8864 ** for a particular application. 8865 */ 8866 SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N); 8867 8868 /* 8869 ** CAPI3REF: Checkpoint a database 8870 ** METHOD: sqlite3 8871 ** 8872 ** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to 8873 ** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^ 8874 ** 8875 ** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the 8876 ** [write-ahead log] for database X on [database connection] D to be 8877 ** transferred into the database file and for the write-ahead log to 8878 ** be reset. See the [checkpointing] documentation for addition 8879 ** information. 8880 ** 8881 ** This interface used to be the only way to cause a checkpoint to 8882 ** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()] 8883 ** interface was added. This interface is retained for backwards 8884 ** compatibility and as a convenience for applications that need to manually 8885 ** start a callback but which do not need the full power (and corresponding 8886 ** complication) of [sqlite3_wal_checkpoint_v2()]. 8887 */ 8888 SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); 8889 8890 /* 8891 ** CAPI3REF: Checkpoint a database 8892 ** METHOD: sqlite3 8893 ** 8894 ** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint 8895 ** operation on database X of [database connection] D in mode M. Status 8896 ** information is written back into integers pointed to by L and C.)^ 8897 ** ^(The M parameter must be a valid [checkpoint mode]:)^ 8898 ** 8899 ** <dl> 8900 ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd> 8901 ** ^Checkpoint as many frames as possible without waiting for any database 8902 ** readers or writers to finish, then sync the database file if all frames 8903 ** in the log were checkpointed. ^The [busy-handler callback] 8904 ** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. 8905 ** ^On the other hand, passive mode might leave the checkpoint unfinished 8906 ** if there are concurrent readers or writers. 8907 ** 8908 ** <dt>SQLITE_CHECKPOINT_FULL<dd> 8909 ** ^This mode blocks (it invokes the 8910 ** [sqlite3_busy_handler|busy-handler callback]) until there is no 8911 ** database writer and all readers are reading from the most recent database 8912 ** snapshot. ^It then checkpoints all frames in the log file and syncs the 8913 ** database file. ^This mode blocks new database writers while it is pending, 8914 ** but new database readers are allowed to continue unimpeded. 8915 ** 8916 ** <dt>SQLITE_CHECKPOINT_RESTART<dd> 8917 ** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition 8918 ** that after checkpointing the log file it blocks (calls the 8919 ** [busy-handler callback]) 8920 ** until all readers are reading from the database file only. ^This ensures 8921 ** that the next writer will restart the log file from the beginning. 8922 ** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new 8923 ** database writer attempts while it is pending, but does not impede readers. 8924 ** 8925 ** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd> 8926 ** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the 8927 ** addition that it also truncates the log file to zero bytes just prior 8928 ** to a successful return. 8929 ** </dl> 8930 ** 8931 ** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in 8932 ** the log file or to -1 if the checkpoint could not run because 8933 ** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not 8934 ** NULL,then *pnCkpt is set to the total number of checkpointed frames in the 8935 ** log file (including any that were already checkpointed before the function 8936 ** was called) or to -1 if the checkpoint could not run due to an error or 8937 ** because the database is not in WAL mode. ^Note that upon successful 8938 ** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been 8939 ** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero. 8940 ** 8941 ** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If 8942 ** any other process is running a checkpoint operation at the same time, the 8943 ** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a 8944 ** busy-handler configured, it will not be invoked in this case. 8945 ** 8946 ** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the 8947 ** exclusive "writer" lock on the database file. ^If the writer lock cannot be 8948 ** obtained immediately, and a busy-handler is configured, it is invoked and 8949 ** the writer lock retried until either the busy-handler returns 0 or the lock 8950 ** is successfully obtained. ^The busy-handler is also invoked while waiting for 8951 ** database readers as described above. ^If the busy-handler returns 0 before 8952 ** the writer lock is obtained or while waiting for database readers, the 8953 ** checkpoint operation proceeds from that point in the same way as 8954 ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible 8955 ** without blocking any further. ^SQLITE_BUSY is returned in this case. 8956 ** 8957 ** ^If parameter zDb is NULL or points to a zero length string, then the 8958 ** specified operation is attempted on all WAL databases [attached] to 8959 ** [database connection] db. In this case the 8960 ** values written to output parameters *pnLog and *pnCkpt are undefined. ^If 8961 ** an SQLITE_BUSY error is encountered when processing one or more of the 8962 ** attached WAL databases, the operation is still attempted on any remaining 8963 ** attached databases and SQLITE_BUSY is returned at the end. ^If any other 8964 ** error occurs while processing an attached database, processing is abandoned 8965 ** and the error code is returned to the caller immediately. ^If no error 8966 ** (SQLITE_BUSY or otherwise) is encountered while processing the attached 8967 ** databases, SQLITE_OK is returned. 8968 ** 8969 ** ^If database zDb is the name of an attached database that is not in WAL 8970 ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If 8971 ** zDb is not NULL (or a zero length string) and is not the name of any 8972 ** attached database, SQLITE_ERROR is returned to the caller. 8973 ** 8974 ** ^Unless it returns SQLITE_MISUSE, 8975 ** the sqlite3_wal_checkpoint_v2() interface 8976 ** sets the error information that is queried by 8977 ** [sqlite3_errcode()] and [sqlite3_errmsg()]. 8978 ** 8979 ** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface 8980 ** from SQL. 8981 */ 8982 SQLITE_API int sqlite3_wal_checkpoint_v2( 8983 sqlite3 *db, /* Database handle */ 8984 const char *zDb, /* Name of attached database (or NULL) */ 8985 int eMode, /* SQLITE_CHECKPOINT_* value */ 8986 int *pnLog, /* OUT: Size of WAL log in frames */ 8987 int *pnCkpt /* OUT: Total number of frames checkpointed */ 8988 ); 8989 8990 /* 8991 ** CAPI3REF: Checkpoint Mode Values 8992 ** KEYWORDS: {checkpoint mode} 8993 ** 8994 ** These constants define all valid values for the "checkpoint mode" passed 8995 ** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface. 8996 ** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the 8997 ** meaning of each of these checkpoint modes. 8998 */ 8999 #define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */ 9000 #define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */ 9001 #define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for for readers */ 9002 #define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */ 9003 9004 /* 9005 ** CAPI3REF: Virtual Table Interface Configuration 9006 ** 9007 ** This function may be called by either the [xConnect] or [xCreate] method 9008 ** of a [virtual table] implementation to configure 9009 ** various facets of the virtual table interface. 9010 ** 9011 ** If this interface is invoked outside the context of an xConnect or 9012 ** xCreate virtual table method then the behavior is undefined. 9013 ** 9014 ** In the call sqlite3_vtab_config(D,C,...) the D parameter is the 9015 ** [database connection] in which the virtual table is being created and 9016 ** which is passed in as the first argument to the [xConnect] or [xCreate] 9017 ** method that is invoking sqlite3_vtab_config(). The C parameter is one 9018 ** of the [virtual table configuration options]. The presence and meaning 9019 ** of parameters after C depend on which [virtual table configuration option] 9020 ** is used. 9021 */ 9022 SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...); 9023 9024 /* 9025 ** CAPI3REF: Virtual Table Configuration Options 9026 ** KEYWORDS: {virtual table configuration options} 9027 ** KEYWORDS: {virtual table configuration option} 9028 ** 9029 ** These macros define the various options to the 9030 ** [sqlite3_vtab_config()] interface that [virtual table] implementations 9031 ** can use to customize and optimize their behavior. 9032 ** 9033 ** <dl> 9034 ** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]] 9035 ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt> 9036 ** <dd>Calls of the form 9037 ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, 9038 ** where X is an integer. If X is zero, then the [virtual table] whose 9039 ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not 9040 ** support constraints. In this configuration (which is the default) if 9041 ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire 9042 ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been 9043 ** specified as part of the users SQL statement, regardless of the actual 9044 ** ON CONFLICT mode specified. 9045 ** 9046 ** If X is non-zero, then the virtual table implementation guarantees 9047 ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before 9048 ** any modifications to internal or persistent data structures have been made. 9049 ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite 9050 ** is able to roll back a statement or database transaction, and abandon 9051 ** or continue processing the current SQL statement as appropriate. 9052 ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns 9053 ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode 9054 ** had been ABORT. 9055 ** 9056 ** Virtual table implementations that are required to handle OR REPLACE 9057 ** must do so within the [xUpdate] method. If a call to the 9058 ** [sqlite3_vtab_on_conflict()] function indicates that the current ON 9059 ** CONFLICT policy is REPLACE, the virtual table implementation should 9060 ** silently replace the appropriate rows within the xUpdate callback and 9061 ** return SQLITE_OK. Or, if this is not possible, it may return 9062 ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT 9063 ** constraint handling. 9064 ** </dd> 9065 ** 9066 ** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt> 9067 ** <dd>Calls of the form 9068 ** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the 9069 ** the [xConnect] or [xCreate] methods of a [virtual table] implmentation 9070 ** prohibits that virtual table from being used from within triggers and 9071 ** views. 9072 ** </dd> 9073 ** 9074 ** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt> 9075 ** <dd>Calls of the form 9076 ** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the 9077 ** the [xConnect] or [xCreate] methods of a [virtual table] implmentation 9078 ** identify that virtual table as being safe to use from within triggers 9079 ** and views. Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the 9080 ** virtual table can do no serious harm even if it is controlled by a 9081 ** malicious hacker. Developers should avoid setting the SQLITE_VTAB_INNOCUOUS 9082 ** flag unless absolutely necessary. 9083 ** </dd> 9084 ** </dl> 9085 */ 9086 #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 9087 #define SQLITE_VTAB_INNOCUOUS 2 9088 #define SQLITE_VTAB_DIRECTONLY 3 9089 9090 /* 9091 ** CAPI3REF: Determine The Virtual Table Conflict Policy 9092 ** 9093 ** This function may only be called from within a call to the [xUpdate] method 9094 ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The 9095 ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], 9096 ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode 9097 ** of the SQL statement that triggered the call to the [xUpdate] method of the 9098 ** [virtual table]. 9099 */ 9100 SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *); 9101 9102 /* 9103 ** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE 9104 ** 9105 ** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn] 9106 ** method of a [virtual table], then it returns true if and only if the 9107 ** column is being fetched as part of an UPDATE operation during which the 9108 ** column value will not change. Applications might use this to substitute 9109 ** a return value that is less expensive to compute and that the corresponding 9110 ** [xUpdate] method understands as a "no-change" value. 9111 ** 9112 ** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that 9113 ** the column is not changed by the UPDATE statement, then the xColumn 9114 ** method can optionally return without setting a result, without calling 9115 ** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces]. 9116 ** In that case, [sqlite3_value_nochange(X)] will return true for the 9117 ** same column in the [xUpdate] method. 9118 */ 9119 SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*); 9120 9121 /* 9122 ** CAPI3REF: Determine The Collation For a Virtual Table Constraint 9123 ** 9124 ** This function may only be called from within a call to the [xBestIndex] 9125 ** method of a [virtual table]. 9126 ** 9127 ** The first argument must be the sqlite3_index_info object that is the 9128 ** first parameter to the xBestIndex() method. The second argument must be 9129 ** an index into the aConstraint[] array belonging to the sqlite3_index_info 9130 ** structure passed to xBestIndex. This function returns a pointer to a buffer 9131 ** containing the name of the collation sequence for the corresponding 9132 ** constraint. 9133 */ 9134 SQLITE_API SQLITE_EXPERIMENTAL const char *sqlite3_vtab_collation(sqlite3_index_info*,int); 9135 9136 /* 9137 ** CAPI3REF: Conflict resolution modes 9138 ** KEYWORDS: {conflict resolution mode} 9139 ** 9140 ** These constants are returned by [sqlite3_vtab_on_conflict()] to 9141 ** inform a [virtual table] implementation what the [ON CONFLICT] mode 9142 ** is for the SQL statement being evaluated. 9143 ** 9144 ** Note that the [SQLITE_IGNORE] constant is also used as a potential 9145 ** return value from the [sqlite3_set_authorizer()] callback and that 9146 ** [SQLITE_ABORT] is also a [result code]. 9147 */ 9148 #define SQLITE_ROLLBACK 1 9149 /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ 9150 #define SQLITE_FAIL 3 9151 /* #define SQLITE_ABORT 4 // Also an error code */ 9152 #define SQLITE_REPLACE 5 9153 9154 /* 9155 ** CAPI3REF: Prepared Statement Scan Status Opcodes 9156 ** KEYWORDS: {scanstatus options} 9157 ** 9158 ** The following constants can be used for the T parameter to the 9159 ** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a 9160 ** different metric for sqlite3_stmt_scanstatus() to return. 9161 ** 9162 ** When the value returned to V is a string, space to hold that string is 9163 ** managed by the prepared statement S and will be automatically freed when 9164 ** S is finalized. 9165 ** 9166 ** <dl> 9167 ** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt> 9168 ** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be 9169 ** set to the total number of times that the X-th loop has run.</dd> 9170 ** 9171 ** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt> 9172 ** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set 9173 ** to the total number of rows examined by all iterations of the X-th loop.</dd> 9174 ** 9175 ** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt> 9176 ** <dd>^The "double" variable pointed to by the V parameter will be set to the 9177 ** query planner's estimate for the average number of rows output from each 9178 ** iteration of the X-th loop. If the query planner's estimates was accurate, 9179 ** then this value will approximate the quotient NVISIT/NLOOP and the 9180 ** product of this value for all prior loops with the same SELECTID will 9181 ** be the NLOOP value for the current loop. 9182 ** 9183 ** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt> 9184 ** <dd>^The "const char *" variable pointed to by the V parameter will be set 9185 ** to a zero-terminated UTF-8 string containing the name of the index or table 9186 ** used for the X-th loop. 9187 ** 9188 ** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt> 9189 ** <dd>^The "const char *" variable pointed to by the V parameter will be set 9190 ** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN] 9191 ** description for the X-th loop. 9192 ** 9193 ** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt> 9194 ** <dd>^The "int" variable pointed to by the V parameter will be set to the 9195 ** "select-id" for the X-th loop. The select-id identifies which query or 9196 ** subquery the loop is part of. The main query has a select-id of zero. 9197 ** The select-id is the same value as is output in the first column 9198 ** of an [EXPLAIN QUERY PLAN] query. 9199 ** </dl> 9200 */ 9201 #define SQLITE_SCANSTAT_NLOOP 0 9202 #define SQLITE_SCANSTAT_NVISIT 1 9203 #define SQLITE_SCANSTAT_EST 2 9204 #define SQLITE_SCANSTAT_NAME 3 9205 #define SQLITE_SCANSTAT_EXPLAIN 4 9206 #define SQLITE_SCANSTAT_SELECTID 5 9207 9208 /* 9209 ** CAPI3REF: Prepared Statement Scan Status 9210 ** METHOD: sqlite3_stmt 9211 ** 9212 ** This interface returns information about the predicted and measured 9213 ** performance for pStmt. Advanced applications can use this 9214 ** interface to compare the predicted and the measured performance and 9215 ** issue warnings and/or rerun [ANALYZE] if discrepancies are found. 9216 ** 9217 ** Since this interface is expected to be rarely used, it is only 9218 ** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS] 9219 ** compile-time option. 9220 ** 9221 ** The "iScanStatusOp" parameter determines which status information to return. 9222 ** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior 9223 ** of this interface is undefined. 9224 ** ^The requested measurement is written into a variable pointed to by 9225 ** the "pOut" parameter. 9226 ** Parameter "idx" identifies the specific loop to retrieve statistics for. 9227 ** Loops are numbered starting from zero. ^If idx is out of range - less than 9228 ** zero or greater than or equal to the total number of loops used to implement 9229 ** the statement - a non-zero value is returned and the variable that pOut 9230 ** points to is unchanged. 9231 ** 9232 ** ^Statistics might not be available for all loops in all statements. ^In cases 9233 ** where there exist loops with no available statistics, this function behaves 9234 ** as if the loop did not exist - it returns non-zero and leave the variable 9235 ** that pOut points to unchanged. 9236 ** 9237 ** See also: [sqlite3_stmt_scanstatus_reset()] 9238 */ 9239 SQLITE_API int sqlite3_stmt_scanstatus( 9240 sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ 9241 int idx, /* Index of loop to report on */ 9242 int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ 9243 void *pOut /* Result written here */ 9244 ); 9245 9246 /* 9247 ** CAPI3REF: Zero Scan-Status Counters 9248 ** METHOD: sqlite3_stmt 9249 ** 9250 ** ^Zero all [sqlite3_stmt_scanstatus()] related event counters. 9251 ** 9252 ** This API is only available if the library is built with pre-processor 9253 ** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. 9254 */ 9255 SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); 9256 9257 /* 9258 ** CAPI3REF: Flush caches to disk mid-transaction 9259 ** 9260 ** ^If a write-transaction is open on [database connection] D when the 9261 ** [sqlite3_db_cacheflush(D)] interface invoked, any dirty 9262 ** pages in the pager-cache that are not currently in use are written out 9263 ** to disk. A dirty page may be in use if a database cursor created by an 9264 ** active SQL statement is reading from it, or if it is page 1 of a database 9265 ** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)] 9266 ** interface flushes caches for all schemas - "main", "temp", and 9267 ** any [attached] databases. 9268 ** 9269 ** ^If this function needs to obtain extra database locks before dirty pages 9270 ** can be flushed to disk, it does so. ^If those locks cannot be obtained 9271 ** immediately and there is a busy-handler callback configured, it is invoked 9272 ** in the usual manner. ^If the required lock still cannot be obtained, then 9273 ** the database is skipped and an attempt made to flush any dirty pages 9274 ** belonging to the next (if any) database. ^If any databases are skipped 9275 ** because locks cannot be obtained, but no other error occurs, this 9276 ** function returns SQLITE_BUSY. 9277 ** 9278 ** ^If any other error occurs while flushing dirty pages to disk (for 9279 ** example an IO error or out-of-memory condition), then processing is 9280 ** abandoned and an SQLite [error code] is returned to the caller immediately. 9281 ** 9282 ** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK. 9283 ** 9284 ** ^This function does not set the database handle error code or message 9285 ** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions. 9286 */ 9287 SQLITE_API int sqlite3_db_cacheflush(sqlite3*); 9288 9289 /* 9290 ** CAPI3REF: The pre-update hook. 9291 ** 9292 ** ^These interfaces are only available if SQLite is compiled using the 9293 ** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option. 9294 ** 9295 ** ^The [sqlite3_preupdate_hook()] interface registers a callback function 9296 ** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation 9297 ** on a database table. 9298 ** ^At most one preupdate hook may be registered at a time on a single 9299 ** [database connection]; each call to [sqlite3_preupdate_hook()] overrides 9300 ** the previous setting. 9301 ** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()] 9302 ** with a NULL pointer as the second parameter. 9303 ** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as 9304 ** the first parameter to callbacks. 9305 ** 9306 ** ^The preupdate hook only fires for changes to real database tables; the 9307 ** preupdate hook is not invoked for changes to [virtual tables] or to 9308 ** system tables like sqlite_master or sqlite_stat1. 9309 ** 9310 ** ^The second parameter to the preupdate callback is a pointer to 9311 ** the [database connection] that registered the preupdate hook. 9312 ** ^The third parameter to the preupdate callback is one of the constants 9313 ** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the 9314 ** kind of update operation that is about to occur. 9315 ** ^(The fourth parameter to the preupdate callback is the name of the 9316 ** database within the database connection that is being modified. This 9317 ** will be "main" for the main database or "temp" for TEMP tables or 9318 ** the name given after the AS keyword in the [ATTACH] statement for attached 9319 ** databases.)^ 9320 ** ^The fifth parameter to the preupdate callback is the name of the 9321 ** table that is being modified. 9322 ** 9323 ** For an UPDATE or DELETE operation on a [rowid table], the sixth 9324 ** parameter passed to the preupdate callback is the initial [rowid] of the 9325 ** row being modified or deleted. For an INSERT operation on a rowid table, 9326 ** or any operation on a WITHOUT ROWID table, the value of the sixth 9327 ** parameter is undefined. For an INSERT or UPDATE on a rowid table the 9328 ** seventh parameter is the final rowid value of the row being inserted 9329 ** or updated. The value of the seventh parameter passed to the callback 9330 ** function is not defined for operations on WITHOUT ROWID tables, or for 9331 ** INSERT operations on rowid tables. 9332 ** 9333 ** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()], 9334 ** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces 9335 ** provide additional information about a preupdate event. These routines 9336 ** may only be called from within a preupdate callback. Invoking any of 9337 ** these routines from outside of a preupdate callback or with a 9338 ** [database connection] pointer that is different from the one supplied 9339 ** to the preupdate callback results in undefined and probably undesirable 9340 ** behavior. 9341 ** 9342 ** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns 9343 ** in the row that is being inserted, updated, or deleted. 9344 ** 9345 ** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to 9346 ** a [protected sqlite3_value] that contains the value of the Nth column of 9347 ** the table row before it is updated. The N parameter must be between 0 9348 ** and one less than the number of columns or the behavior will be 9349 ** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE 9350 ** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the 9351 ** behavior is undefined. The [sqlite3_value] that P points to 9352 ** will be destroyed when the preupdate callback returns. 9353 ** 9354 ** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to 9355 ** a [protected sqlite3_value] that contains the value of the Nth column of 9356 ** the table row after it is updated. The N parameter must be between 0 9357 ** and one less than the number of columns or the behavior will be 9358 ** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE 9359 ** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the 9360 ** behavior is undefined. The [sqlite3_value] that P points to 9361 ** will be destroyed when the preupdate callback returns. 9362 ** 9363 ** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate 9364 ** callback was invoked as a result of a direct insert, update, or delete 9365 ** operation; or 1 for inserts, updates, or deletes invoked by top-level 9366 ** triggers; or 2 for changes resulting from triggers called by top-level 9367 ** triggers; and so forth. 9368 ** 9369 ** See also: [sqlite3_update_hook()] 9370 */ 9371 #if defined(SQLITE_ENABLE_PREUPDATE_HOOK) 9372 SQLITE_API void *sqlite3_preupdate_hook( 9373 sqlite3 *db, 9374 void(*xPreUpdate)( 9375 void *pCtx, /* Copy of third arg to preupdate_hook() */ 9376 sqlite3 *db, /* Database handle */ 9377 int op, /* SQLITE_UPDATE, DELETE or INSERT */ 9378 char const *zDb, /* Database name */ 9379 char const *zName, /* Table name */ 9380 sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */ 9381 sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */ 9382 ), 9383 void* 9384 ); 9385 SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **); 9386 SQLITE_API int sqlite3_preupdate_count(sqlite3 *); 9387 SQLITE_API int sqlite3_preupdate_depth(sqlite3 *); 9388 SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **); 9389 #endif 9390 9391 /* 9392 ** CAPI3REF: Low-level system error code 9393 ** 9394 ** ^Attempt to return the underlying operating system error code or error 9395 ** number that caused the most recent I/O error or failure to open a file. 9396 ** The return value is OS-dependent. For example, on unix systems, after 9397 ** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be 9398 ** called to get back the underlying "errno" that caused the problem, such 9399 ** as ENOSPC, EAUTH, EISDIR, and so forth. 9400 */ 9401 SQLITE_API int sqlite3_system_errno(sqlite3*); 9402 9403 /* 9404 ** CAPI3REF: Database Snapshot 9405 ** KEYWORDS: {snapshot} {sqlite3_snapshot} 9406 ** 9407 ** An instance of the snapshot object records the state of a [WAL mode] 9408 ** database for some specific point in history. 9409 ** 9410 ** In [WAL mode], multiple [database connections] that are open on the 9411 ** same database file can each be reading a different historical version 9412 ** of the database file. When a [database connection] begins a read 9413 ** transaction, that connection sees an unchanging copy of the database 9414 ** as it existed for the point in time when the transaction first started. 9415 ** Subsequent changes to the database from other connections are not seen 9416 ** by the reader until a new read transaction is started. 9417 ** 9418 ** The sqlite3_snapshot object records state information about an historical 9419 ** version of the database file so that it is possible to later open a new read 9420 ** transaction that sees that historical version of the database rather than 9421 ** the most recent version. 9422 */ 9423 typedef struct sqlite3_snapshot { 9424 unsigned char hidden[48]; 9425 } sqlite3_snapshot; 9426 9427 /* 9428 ** CAPI3REF: Record A Database Snapshot 9429 ** CONSTRUCTOR: sqlite3_snapshot 9430 ** 9431 ** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a 9432 ** new [sqlite3_snapshot] object that records the current state of 9433 ** schema S in database connection D. ^On success, the 9434 ** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly 9435 ** created [sqlite3_snapshot] object into *P and returns SQLITE_OK. 9436 ** If there is not already a read-transaction open on schema S when 9437 ** this function is called, one is opened automatically. 9438 ** 9439 ** The following must be true for this function to succeed. If any of 9440 ** the following statements are false when sqlite3_snapshot_get() is 9441 ** called, SQLITE_ERROR is returned. The final value of *P is undefined 9442 ** in this case. 9443 ** 9444 ** <ul> 9445 ** <li> The database handle must not be in [autocommit mode]. 9446 ** 9447 ** <li> Schema S of [database connection] D must be a [WAL mode] database. 9448 ** 9449 ** <li> There must not be a write transaction open on schema S of database 9450 ** connection D. 9451 ** 9452 ** <li> One or more transactions must have been written to the current wal 9453 ** file since it was created on disk (by any connection). This means 9454 ** that a snapshot cannot be taken on a wal mode database with no wal 9455 ** file immediately after it is first opened. At least one transaction 9456 ** must be written to it first. 9457 ** </ul> 9458 ** 9459 ** This function may also return SQLITE_NOMEM. If it is called with the 9460 ** database handle in autocommit mode but fails for some other reason, 9461 ** whether or not a read transaction is opened on schema S is undefined. 9462 ** 9463 ** The [sqlite3_snapshot] object returned from a successful call to 9464 ** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()] 9465 ** to avoid a memory leak. 9466 ** 9467 ** The [sqlite3_snapshot_get()] interface is only available when the 9468 ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 9469 */ 9470 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get( 9471 sqlite3 *db, 9472 const char *zSchema, 9473 sqlite3_snapshot **ppSnapshot 9474 ); 9475 9476 /* 9477 ** CAPI3REF: Start a read transaction on an historical snapshot 9478 ** METHOD: sqlite3_snapshot 9479 ** 9480 ** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read 9481 ** transaction or upgrades an existing one for schema S of 9482 ** [database connection] D such that the read transaction refers to 9483 ** historical [snapshot] P, rather than the most recent change to the 9484 ** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK 9485 ** on success or an appropriate [error code] if it fails. 9486 ** 9487 ** ^In order to succeed, the database connection must not be in 9488 ** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there 9489 ** is already a read transaction open on schema S, then the database handle 9490 ** must have no active statements (SELECT statements that have been passed 9491 ** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()). 9492 ** SQLITE_ERROR is returned if either of these conditions is violated, or 9493 ** if schema S does not exist, or if the snapshot object is invalid. 9494 ** 9495 ** ^A call to sqlite3_snapshot_open() will fail to open if the specified 9496 ** snapshot has been overwritten by a [checkpoint]. In this case 9497 ** SQLITE_ERROR_SNAPSHOT is returned. 9498 ** 9499 ** If there is already a read transaction open when this function is 9500 ** invoked, then the same read transaction remains open (on the same 9501 ** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT 9502 ** is returned. If another error code - for example SQLITE_PROTOCOL or an 9503 ** SQLITE_IOERR error code - is returned, then the final state of the 9504 ** read transaction is undefined. If SQLITE_OK is returned, then the 9505 ** read transaction is now open on database snapshot P. 9506 ** 9507 ** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the 9508 ** database connection D does not know that the database file for 9509 ** schema S is in [WAL mode]. A database connection might not know 9510 ** that the database file is in [WAL mode] if there has been no prior 9511 ** I/O on that database connection, or if the database entered [WAL mode] 9512 ** after the most recent I/O on the database connection.)^ 9513 ** (Hint: Run "[PRAGMA application_id]" against a newly opened 9514 ** database connection in order to make it ready to use snapshots.) 9515 ** 9516 ** The [sqlite3_snapshot_open()] interface is only available when the 9517 ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 9518 */ 9519 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open( 9520 sqlite3 *db, 9521 const char *zSchema, 9522 sqlite3_snapshot *pSnapshot 9523 ); 9524 9525 /* 9526 ** CAPI3REF: Destroy a snapshot 9527 ** DESTRUCTOR: sqlite3_snapshot 9528 ** 9529 ** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P. 9530 ** The application must eventually free every [sqlite3_snapshot] object 9531 ** using this routine to avoid a memory leak. 9532 ** 9533 ** The [sqlite3_snapshot_free()] interface is only available when the 9534 ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 9535 */ 9536 SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*); 9537 9538 /* 9539 ** CAPI3REF: Compare the ages of two snapshot handles. 9540 ** METHOD: sqlite3_snapshot 9541 ** 9542 ** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages 9543 ** of two valid snapshot handles. 9544 ** 9545 ** If the two snapshot handles are not associated with the same database 9546 ** file, the result of the comparison is undefined. 9547 ** 9548 ** Additionally, the result of the comparison is only valid if both of the 9549 ** snapshot handles were obtained by calling sqlite3_snapshot_get() since the 9550 ** last time the wal file was deleted. The wal file is deleted when the 9551 ** database is changed back to rollback mode or when the number of database 9552 ** clients drops to zero. If either snapshot handle was obtained before the 9553 ** wal file was last deleted, the value returned by this function 9554 ** is undefined. 9555 ** 9556 ** Otherwise, this API returns a negative value if P1 refers to an older 9557 ** snapshot than P2, zero if the two handles refer to the same database 9558 ** snapshot, and a positive value if P1 is a newer snapshot than P2. 9559 ** 9560 ** This interface is only available if SQLite is compiled with the 9561 ** [SQLITE_ENABLE_SNAPSHOT] option. 9562 */ 9563 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp( 9564 sqlite3_snapshot *p1, 9565 sqlite3_snapshot *p2 9566 ); 9567 9568 /* 9569 ** CAPI3REF: Recover snapshots from a wal file 9570 ** METHOD: sqlite3_snapshot 9571 ** 9572 ** If a [WAL file] remains on disk after all database connections close 9573 ** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control] 9574 ** or because the last process to have the database opened exited without 9575 ** calling [sqlite3_close()]) and a new connection is subsequently opened 9576 ** on that database and [WAL file], the [sqlite3_snapshot_open()] interface 9577 ** will only be able to open the last transaction added to the WAL file 9578 ** even though the WAL file contains other valid transactions. 9579 ** 9580 ** This function attempts to scan the WAL file associated with database zDb 9581 ** of database handle db and make all valid snapshots available to 9582 ** sqlite3_snapshot_open(). It is an error if there is already a read 9583 ** transaction open on the database, or if the database is not a WAL mode 9584 ** database. 9585 ** 9586 ** SQLITE_OK is returned if successful, or an SQLite error code otherwise. 9587 ** 9588 ** This interface is only available if SQLite is compiled with the 9589 ** [SQLITE_ENABLE_SNAPSHOT] option. 9590 */ 9591 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb); 9592 9593 /* 9594 ** CAPI3REF: Serialize a database 9595 ** 9596 ** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory 9597 ** that is a serialization of the S database on [database connection] D. 9598 ** If P is not a NULL pointer, then the size of the database in bytes 9599 ** is written into *P. 9600 ** 9601 ** For an ordinary on-disk database file, the serialization is just a 9602 ** copy of the disk file. For an in-memory database or a "TEMP" database, 9603 ** the serialization is the same sequence of bytes which would be written 9604 ** to disk if that database where backed up to disk. 9605 ** 9606 ** The usual case is that sqlite3_serialize() copies the serialization of 9607 ** the database into memory obtained from [sqlite3_malloc64()] and returns 9608 ** a pointer to that memory. The caller is responsible for freeing the 9609 ** returned value to avoid a memory leak. However, if the F argument 9610 ** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations 9611 ** are made, and the sqlite3_serialize() function will return a pointer 9612 ** to the contiguous memory representation of the database that SQLite 9613 ** is currently using for that database, or NULL if the no such contiguous 9614 ** memory representation of the database exists. A contiguous memory 9615 ** representation of the database will usually only exist if there has 9616 ** been a prior call to [sqlite3_deserialize(D,S,...)] with the same 9617 ** values of D and S. 9618 ** The size of the database is written into *P even if the 9619 ** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy 9620 ** of the database exists. 9621 ** 9622 ** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the 9623 ** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory 9624 ** allocation error occurs. 9625 ** 9626 ** This interface is only available if SQLite is compiled with the 9627 ** [SQLITE_ENABLE_DESERIALIZE] option. 9628 */ 9629 SQLITE_API unsigned char *sqlite3_serialize( 9630 sqlite3 *db, /* The database connection */ 9631 const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */ 9632 sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */ 9633 unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */ 9634 ); 9635 9636 /* 9637 ** CAPI3REF: Flags for sqlite3_serialize 9638 ** 9639 ** Zero or more of the following constants can be OR-ed together for 9640 ** the F argument to [sqlite3_serialize(D,S,P,F)]. 9641 ** 9642 ** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return 9643 ** a pointer to contiguous in-memory database that it is currently using, 9644 ** without making a copy of the database. If SQLite is not currently using 9645 ** a contiguous in-memory database, then this option causes 9646 ** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be 9647 ** using a contiguous in-memory database if it has been initialized by a 9648 ** prior call to [sqlite3_deserialize()]. 9649 */ 9650 #define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */ 9651 9652 /* 9653 ** CAPI3REF: Deserialize a database 9654 ** 9655 ** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the 9656 ** [database connection] D to disconnect from database S and then 9657 ** reopen S as an in-memory database based on the serialization contained 9658 ** in P. The serialized database P is N bytes in size. M is the size of 9659 ** the buffer P, which might be larger than N. If M is larger than N, and 9660 ** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is 9661 ** permitted to add content to the in-memory database as long as the total 9662 ** size does not exceed M bytes. 9663 ** 9664 ** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will 9665 ** invoke sqlite3_free() on the serialization buffer when the database 9666 ** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then 9667 ** SQLite will try to increase the buffer size using sqlite3_realloc64() 9668 ** if writes on the database cause it to grow larger than M bytes. 9669 ** 9670 ** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the 9671 ** database is currently in a read transaction or is involved in a backup 9672 ** operation. 9673 ** 9674 ** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the 9675 ** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then 9676 ** [sqlite3_free()] is invoked on argument P prior to returning. 9677 ** 9678 ** This interface is only available if SQLite is compiled with the 9679 ** [SQLITE_ENABLE_DESERIALIZE] option. 9680 */ 9681 SQLITE_API int sqlite3_deserialize( 9682 sqlite3 *db, /* The database connection */ 9683 const char *zSchema, /* Which DB to reopen with the deserialization */ 9684 unsigned char *pData, /* The serialized database content */ 9685 sqlite3_int64 szDb, /* Number bytes in the deserialization */ 9686 sqlite3_int64 szBuf, /* Total size of buffer pData[] */ 9687 unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */ 9688 ); 9689 9690 /* 9691 ** CAPI3REF: Flags for sqlite3_deserialize() 9692 ** 9693 ** The following are allowed values for 6th argument (the F argument) to 9694 ** the [sqlite3_deserialize(D,S,P,N,M,F)] interface. 9695 ** 9696 ** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization 9697 ** in the P argument is held in memory obtained from [sqlite3_malloc64()] 9698 ** and that SQLite should take ownership of this memory and automatically 9699 ** free it when it has finished using it. Without this flag, the caller 9700 ** is responsible for freeing any dynamically allocated memory. 9701 ** 9702 ** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to 9703 ** grow the size of the database using calls to [sqlite3_realloc64()]. This 9704 ** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used. 9705 ** Without this flag, the deserialized database cannot increase in size beyond 9706 ** the number of bytes specified by the M parameter. 9707 ** 9708 ** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database 9709 ** should be treated as read-only. 9710 */ 9711 #define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */ 9712 #define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */ 9713 #define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */ 9714 9715 /* 9716 ** Undo the hack that converts floating point types to integer for 9717 ** builds on processors without floating point support. 9718 */ 9719 #ifdef SQLITE_OMIT_FLOATING_POINT 9720 # undef double 9721 #endif 9722 9723 #ifdef __cplusplus 9724 } /* End of the 'extern "C"' block */ 9725 #endif 9726 #endif /* SQLITE3_H */ 9727 9728 /******** Begin file sqlite3rtree.h *********/ 9729 /* 9730 ** 2010 August 30 9731 ** 9732 ** The author disclaims copyright to this source code. In place of 9733 ** a legal notice, here is a blessing: 9734 ** 9735 ** May you do good and not evil. 9736 ** May you find forgiveness for yourself and forgive others. 9737 ** May you share freely, never taking more than you give. 9738 ** 9739 ************************************************************************* 9740 */ 9741 9742 #ifndef _SQLITE3RTREE_H_ 9743 #define _SQLITE3RTREE_H_ 9744 9745 9746 #ifdef __cplusplus 9747 extern "C" { 9748 #endif 9749 9750 typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry; 9751 typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info; 9752 9753 /* The double-precision datatype used by RTree depends on the 9754 ** SQLITE_RTREE_INT_ONLY compile-time option. 9755 */ 9756 #ifdef SQLITE_RTREE_INT_ONLY 9757 typedef sqlite3_int64 sqlite3_rtree_dbl; 9758 #else 9759 typedef double sqlite3_rtree_dbl; 9760 #endif 9761 9762 /* 9763 ** Register a geometry callback named zGeom that can be used as part of an 9764 ** R-Tree geometry query as follows: 9765 ** 9766 ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...) 9767 */ 9768 SQLITE_API int sqlite3_rtree_geometry_callback( 9769 sqlite3 *db, 9770 const char *zGeom, 9771 int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*), 9772 void *pContext 9773 ); 9774 9775 9776 /* 9777 ** A pointer to a structure of the following type is passed as the first 9778 ** argument to callbacks registered using rtree_geometry_callback(). 9779 */ 9780 struct sqlite3_rtree_geometry { 9781 void *pContext; /* Copy of pContext passed to s_r_g_c() */ 9782 int nParam; /* Size of array aParam[] */ 9783 sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */ 9784 void *pUser; /* Callback implementation user data */ 9785 void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */ 9786 }; 9787 9788 /* 9789 ** Register a 2nd-generation geometry callback named zScore that can be 9790 ** used as part of an R-Tree geometry query as follows: 9791 ** 9792 ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...) 9793 */ 9794 SQLITE_API int sqlite3_rtree_query_callback( 9795 sqlite3 *db, 9796 const char *zQueryFunc, 9797 int (*xQueryFunc)(sqlite3_rtree_query_info*), 9798 void *pContext, 9799 void (*xDestructor)(void*) 9800 ); 9801 9802 9803 /* 9804 ** A pointer to a structure of the following type is passed as the 9805 ** argument to scored geometry callback registered using 9806 ** sqlite3_rtree_query_callback(). 9807 ** 9808 ** Note that the first 5 fields of this structure are identical to 9809 ** sqlite3_rtree_geometry. This structure is a subclass of 9810 ** sqlite3_rtree_geometry. 9811 */ 9812 struct sqlite3_rtree_query_info { 9813 void *pContext; /* pContext from when function registered */ 9814 int nParam; /* Number of function parameters */ 9815 sqlite3_rtree_dbl *aParam; /* value of function parameters */ 9816 void *pUser; /* callback can use this, if desired */ 9817 void (*xDelUser)(void*); /* function to free pUser */ 9818 sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */ 9819 unsigned int *anQueue; /* Number of pending entries in the queue */ 9820 int nCoord; /* Number of coordinates */ 9821 int iLevel; /* Level of current node or entry */ 9822 int mxLevel; /* The largest iLevel value in the tree */ 9823 sqlite3_int64 iRowid; /* Rowid for current entry */ 9824 sqlite3_rtree_dbl rParentScore; /* Score of parent node */ 9825 int eParentWithin; /* Visibility of parent node */ 9826 int eWithin; /* OUT: Visibility */ 9827 sqlite3_rtree_dbl rScore; /* OUT: Write the score here */ 9828 /* The following fields are only available in 3.8.11 and later */ 9829 sqlite3_value **apSqlParam; /* Original SQL values of parameters */ 9830 }; 9831 9832 /* 9833 ** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin. 9834 */ 9835 #define NOT_WITHIN 0 /* Object completely outside of query region */ 9836 #define PARTLY_WITHIN 1 /* Object partially overlaps query region */ 9837 #define FULLY_WITHIN 2 /* Object fully contained within query region */ 9838 9839 9840 #ifdef __cplusplus 9841 } /* end of the 'extern "C"' block */ 9842 #endif 9843 9844 #endif /* ifndef _SQLITE3RTREE_H_ */ 9845 9846 /******** End of sqlite3rtree.h *********/ 9847 /******** Begin file sqlite3session.h *********/ 9848 9849 #if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) 9850 #define __SQLITESESSION_H_ 1 9851 9852 /* 9853 ** Make sure we can call this stuff from C++. 9854 */ 9855 #ifdef __cplusplus 9856 extern "C" { 9857 #endif 9858 9859 9860 /* 9861 ** CAPI3REF: Session Object Handle 9862 ** 9863 ** An instance of this object is a [session] that can be used to 9864 ** record changes to a database. 9865 */ 9866 typedef struct sqlite3_session sqlite3_session; 9867 9868 /* 9869 ** CAPI3REF: Changeset Iterator Handle 9870 ** 9871 ** An instance of this object acts as a cursor for iterating 9872 ** over the elements of a [changeset] or [patchset]. 9873 */ 9874 typedef struct sqlite3_changeset_iter sqlite3_changeset_iter; 9875 9876 /* 9877 ** CAPI3REF: Create A New Session Object 9878 ** CONSTRUCTOR: sqlite3_session 9879 ** 9880 ** Create a new session object attached to database handle db. If successful, 9881 ** a pointer to the new object is written to *ppSession and SQLITE_OK is 9882 ** returned. If an error occurs, *ppSession is set to NULL and an SQLite 9883 ** error code (e.g. SQLITE_NOMEM) is returned. 9884 ** 9885 ** It is possible to create multiple session objects attached to a single 9886 ** database handle. 9887 ** 9888 ** Session objects created using this function should be deleted using the 9889 ** [sqlite3session_delete()] function before the database handle that they 9890 ** are attached to is itself closed. If the database handle is closed before 9891 ** the session object is deleted, then the results of calling any session 9892 ** module function, including [sqlite3session_delete()] on the session object 9893 ** are undefined. 9894 ** 9895 ** Because the session module uses the [sqlite3_preupdate_hook()] API, it 9896 ** is not possible for an application to register a pre-update hook on a 9897 ** database handle that has one or more session objects attached. Nor is 9898 ** it possible to create a session object attached to a database handle for 9899 ** which a pre-update hook is already defined. The results of attempting 9900 ** either of these things are undefined. 9901 ** 9902 ** The session object will be used to create changesets for tables in 9903 ** database zDb, where zDb is either "main", or "temp", or the name of an 9904 ** attached database. It is not an error if database zDb is not attached 9905 ** to the database when the session object is created. 9906 */ 9907 SQLITE_API int sqlite3session_create( 9908 sqlite3 *db, /* Database handle */ 9909 const char *zDb, /* Name of db (e.g. "main") */ 9910 sqlite3_session **ppSession /* OUT: New session object */ 9911 ); 9912 9913 /* 9914 ** CAPI3REF: Delete A Session Object 9915 ** DESTRUCTOR: sqlite3_session 9916 ** 9917 ** Delete a session object previously allocated using 9918 ** [sqlite3session_create()]. Once a session object has been deleted, the 9919 ** results of attempting to use pSession with any other session module 9920 ** function are undefined. 9921 ** 9922 ** Session objects must be deleted before the database handle to which they 9923 ** are attached is closed. Refer to the documentation for 9924 ** [sqlite3session_create()] for details. 9925 */ 9926 SQLITE_API void sqlite3session_delete(sqlite3_session *pSession); 9927 9928 9929 /* 9930 ** CAPI3REF: Enable Or Disable A Session Object 9931 ** METHOD: sqlite3_session 9932 ** 9933 ** Enable or disable the recording of changes by a session object. When 9934 ** enabled, a session object records changes made to the database. When 9935 ** disabled - it does not. A newly created session object is enabled. 9936 ** Refer to the documentation for [sqlite3session_changeset()] for further 9937 ** details regarding how enabling and disabling a session object affects 9938 ** the eventual changesets. 9939 ** 9940 ** Passing zero to this function disables the session. Passing a value 9941 ** greater than zero enables it. Passing a value less than zero is a 9942 ** no-op, and may be used to query the current state of the session. 9943 ** 9944 ** The return value indicates the final state of the session object: 0 if 9945 ** the session is disabled, or 1 if it is enabled. 9946 */ 9947 SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable); 9948 9949 /* 9950 ** CAPI3REF: Set Or Clear the Indirect Change Flag 9951 ** METHOD: sqlite3_session 9952 ** 9953 ** Each change recorded by a session object is marked as either direct or 9954 ** indirect. A change is marked as indirect if either: 9955 ** 9956 ** <ul> 9957 ** <li> The session object "indirect" flag is set when the change is 9958 ** made, or 9959 ** <li> The change is made by an SQL trigger or foreign key action 9960 ** instead of directly as a result of a users SQL statement. 9961 ** </ul> 9962 ** 9963 ** If a single row is affected by more than one operation within a session, 9964 ** then the change is considered indirect if all operations meet the criteria 9965 ** for an indirect change above, or direct otherwise. 9966 ** 9967 ** This function is used to set, clear or query the session object indirect 9968 ** flag. If the second argument passed to this function is zero, then the 9969 ** indirect flag is cleared. If it is greater than zero, the indirect flag 9970 ** is set. Passing a value less than zero does not modify the current value 9971 ** of the indirect flag, and may be used to query the current state of the 9972 ** indirect flag for the specified session object. 9973 ** 9974 ** The return value indicates the final state of the indirect flag: 0 if 9975 ** it is clear, or 1 if it is set. 9976 */ 9977 SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect); 9978 9979 /* 9980 ** CAPI3REF: Attach A Table To A Session Object 9981 ** METHOD: sqlite3_session 9982 ** 9983 ** If argument zTab is not NULL, then it is the name of a table to attach 9984 ** to the session object passed as the first argument. All subsequent changes 9985 ** made to the table while the session object is enabled will be recorded. See 9986 ** documentation for [sqlite3session_changeset()] for further details. 9987 ** 9988 ** Or, if argument zTab is NULL, then changes are recorded for all tables 9989 ** in the database. If additional tables are added to the database (by 9990 ** executing "CREATE TABLE" statements) after this call is made, changes for 9991 ** the new tables are also recorded. 9992 ** 9993 ** Changes can only be recorded for tables that have a PRIMARY KEY explicitly 9994 ** defined as part of their CREATE TABLE statement. It does not matter if the 9995 ** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY 9996 ** KEY may consist of a single column, or may be a composite key. 9997 ** 9998 ** It is not an error if the named table does not exist in the database. Nor 9999 ** is it an error if the named table does not have a PRIMARY KEY. However, 10000 ** no changes will be recorded in either of these scenarios. 10001 ** 10002 ** Changes are not recorded for individual rows that have NULL values stored 10003 ** in one or more of their PRIMARY KEY columns. 10004 ** 10005 ** SQLITE_OK is returned if the call completes without error. Or, if an error 10006 ** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned. 10007 ** 10008 ** <h3>Special sqlite_stat1 Handling</h3> 10009 ** 10010 ** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to 10011 ** some of the rules above. In SQLite, the schema of sqlite_stat1 is: 10012 ** <pre> 10013 ** CREATE TABLE sqlite_stat1(tbl,idx,stat) 10014 ** </pre> 10015 ** 10016 ** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are 10017 ** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes 10018 ** are recorded for rows for which (idx IS NULL) is true. However, for such 10019 ** rows a zero-length blob (SQL value X'') is stored in the changeset or 10020 ** patchset instead of a NULL value. This allows such changesets to be 10021 ** manipulated by legacy implementations of sqlite3changeset_invert(), 10022 ** concat() and similar. 10023 ** 10024 ** The sqlite3changeset_apply() function automatically converts the 10025 ** zero-length blob back to a NULL value when updating the sqlite_stat1 10026 ** table. However, if the application calls sqlite3changeset_new(), 10027 ** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset 10028 ** iterator directly (including on a changeset iterator passed to a 10029 ** conflict-handler callback) then the X'' value is returned. The application 10030 ** must translate X'' to NULL itself if required. 10031 ** 10032 ** Legacy (older than 3.22.0) versions of the sessions module cannot capture 10033 ** changes made to the sqlite_stat1 table. Legacy versions of the 10034 ** sqlite3changeset_apply() function silently ignore any modifications to the 10035 ** sqlite_stat1 table that are part of a changeset or patchset. 10036 */ 10037 SQLITE_API int sqlite3session_attach( 10038 sqlite3_session *pSession, /* Session object */ 10039 const char *zTab /* Table name */ 10040 ); 10041 10042 /* 10043 ** CAPI3REF: Set a table filter on a Session Object. 10044 ** METHOD: sqlite3_session 10045 ** 10046 ** The second argument (xFilter) is the "filter callback". For changes to rows 10047 ** in tables that are not attached to the Session object, the filter is called 10048 ** to determine whether changes to the table's rows should be tracked or not. 10049 ** If xFilter returns 0, changes are not tracked. Note that once a table is 10050 ** attached, xFilter will not be called again. 10051 */ 10052 SQLITE_API void sqlite3session_table_filter( 10053 sqlite3_session *pSession, /* Session object */ 10054 int(*xFilter)( 10055 void *pCtx, /* Copy of third arg to _filter_table() */ 10056 const char *zTab /* Table name */ 10057 ), 10058 void *pCtx /* First argument passed to xFilter */ 10059 ); 10060 10061 /* 10062 ** CAPI3REF: Generate A Changeset From A Session Object 10063 ** METHOD: sqlite3_session 10064 ** 10065 ** Obtain a changeset containing changes to the tables attached to the 10066 ** session object passed as the first argument. If successful, 10067 ** set *ppChangeset to point to a buffer containing the changeset 10068 ** and *pnChangeset to the size of the changeset in bytes before returning 10069 ** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to 10070 ** zero and return an SQLite error code. 10071 ** 10072 ** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes, 10073 ** each representing a change to a single row of an attached table. An INSERT 10074 ** change contains the values of each field of a new database row. A DELETE 10075 ** contains the original values of each field of a deleted database row. An 10076 ** UPDATE change contains the original values of each field of an updated 10077 ** database row along with the updated values for each updated non-primary-key 10078 ** column. It is not possible for an UPDATE change to represent a change that 10079 ** modifies the values of primary key columns. If such a change is made, it 10080 ** is represented in a changeset as a DELETE followed by an INSERT. 10081 ** 10082 ** Changes are not recorded for rows that have NULL values stored in one or 10083 ** more of their PRIMARY KEY columns. If such a row is inserted or deleted, 10084 ** no corresponding change is present in the changesets returned by this 10085 ** function. If an existing row with one or more NULL values stored in 10086 ** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL, 10087 ** only an INSERT is appears in the changeset. Similarly, if an existing row 10088 ** with non-NULL PRIMARY KEY values is updated so that one or more of its 10089 ** PRIMARY KEY columns are set to NULL, the resulting changeset contains a 10090 ** DELETE change only. 10091 ** 10092 ** The contents of a changeset may be traversed using an iterator created 10093 ** using the [sqlite3changeset_start()] API. A changeset may be applied to 10094 ** a database with a compatible schema using the [sqlite3changeset_apply()] 10095 ** API. 10096 ** 10097 ** Within a changeset generated by this function, all changes related to a 10098 ** single table are grouped together. In other words, when iterating through 10099 ** a changeset or when applying a changeset to a database, all changes related 10100 ** to a single table are processed before moving on to the next table. Tables 10101 ** are sorted in the same order in which they were attached (or auto-attached) 10102 ** to the sqlite3_session object. The order in which the changes related to 10103 ** a single table are stored is undefined. 10104 ** 10105 ** Following a successful call to this function, it is the responsibility of 10106 ** the caller to eventually free the buffer that *ppChangeset points to using 10107 ** [sqlite3_free()]. 10108 ** 10109 ** <h3>Changeset Generation</h3> 10110 ** 10111 ** Once a table has been attached to a session object, the session object 10112 ** records the primary key values of all new rows inserted into the table. 10113 ** It also records the original primary key and other column values of any 10114 ** deleted or updated rows. For each unique primary key value, data is only 10115 ** recorded once - the first time a row with said primary key is inserted, 10116 ** updated or deleted in the lifetime of the session. 10117 ** 10118 ** There is one exception to the previous paragraph: when a row is inserted, 10119 ** updated or deleted, if one or more of its primary key columns contain a 10120 ** NULL value, no record of the change is made. 10121 ** 10122 ** The session object therefore accumulates two types of records - those 10123 ** that consist of primary key values only (created when the user inserts 10124 ** a new record) and those that consist of the primary key values and the 10125 ** original values of other table columns (created when the users deletes 10126 ** or updates a record). 10127 ** 10128 ** When this function is called, the requested changeset is created using 10129 ** both the accumulated records and the current contents of the database 10130 ** file. Specifically: 10131 ** 10132 ** <ul> 10133 ** <li> For each record generated by an insert, the database is queried 10134 ** for a row with a matching primary key. If one is found, an INSERT 10135 ** change is added to the changeset. If no such row is found, no change 10136 ** is added to the changeset. 10137 ** 10138 ** <li> For each record generated by an update or delete, the database is 10139 ** queried for a row with a matching primary key. If such a row is 10140 ** found and one or more of the non-primary key fields have been 10141 ** modified from their original values, an UPDATE change is added to 10142 ** the changeset. Or, if no such row is found in the table, a DELETE 10143 ** change is added to the changeset. If there is a row with a matching 10144 ** primary key in the database, but all fields contain their original 10145 ** values, no change is added to the changeset. 10146 ** </ul> 10147 ** 10148 ** This means, amongst other things, that if a row is inserted and then later 10149 ** deleted while a session object is active, neither the insert nor the delete 10150 ** will be present in the changeset. Or if a row is deleted and then later a 10151 ** row with the same primary key values inserted while a session object is 10152 ** active, the resulting changeset will contain an UPDATE change instead of 10153 ** a DELETE and an INSERT. 10154 ** 10155 ** When a session object is disabled (see the [sqlite3session_enable()] API), 10156 ** it does not accumulate records when rows are inserted, updated or deleted. 10157 ** This may appear to have some counter-intuitive effects if a single row 10158 ** is written to more than once during a session. For example, if a row 10159 ** is inserted while a session object is enabled, then later deleted while 10160 ** the same session object is disabled, no INSERT record will appear in the 10161 ** changeset, even though the delete took place while the session was disabled. 10162 ** Or, if one field of a row is updated while a session is disabled, and 10163 ** another field of the same row is updated while the session is enabled, the 10164 ** resulting changeset will contain an UPDATE change that updates both fields. 10165 */ 10166 SQLITE_API int sqlite3session_changeset( 10167 sqlite3_session *pSession, /* Session object */ 10168 int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */ 10169 void **ppChangeset /* OUT: Buffer containing changeset */ 10170 ); 10171 10172 /* 10173 ** CAPI3REF: Load The Difference Between Tables Into A Session 10174 ** METHOD: sqlite3_session 10175 ** 10176 ** If it is not already attached to the session object passed as the first 10177 ** argument, this function attaches table zTbl in the same manner as the 10178 ** [sqlite3session_attach()] function. If zTbl does not exist, or if it 10179 ** does not have a primary key, this function is a no-op (but does not return 10180 ** an error). 10181 ** 10182 ** Argument zFromDb must be the name of a database ("main", "temp" etc.) 10183 ** attached to the same database handle as the session object that contains 10184 ** a table compatible with the table attached to the session by this function. 10185 ** A table is considered compatible if it: 10186 ** 10187 ** <ul> 10188 ** <li> Has the same name, 10189 ** <li> Has the same set of columns declared in the same order, and 10190 ** <li> Has the same PRIMARY KEY definition. 10191 ** </ul> 10192 ** 10193 ** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables 10194 ** are compatible but do not have any PRIMARY KEY columns, it is not an error 10195 ** but no changes are added to the session object. As with other session 10196 ** APIs, tables without PRIMARY KEYs are simply ignored. 10197 ** 10198 ** This function adds a set of changes to the session object that could be 10199 ** used to update the table in database zFrom (call this the "from-table") 10200 ** so that its content is the same as the table attached to the session 10201 ** object (call this the "to-table"). Specifically: 10202 ** 10203 ** <ul> 10204 ** <li> For each row (primary key) that exists in the to-table but not in 10205 ** the from-table, an INSERT record is added to the session object. 10206 ** 10207 ** <li> For each row (primary key) that exists in the to-table but not in 10208 ** the from-table, a DELETE record is added to the session object. 10209 ** 10210 ** <li> For each row (primary key) that exists in both tables, but features 10211 ** different non-PK values in each, an UPDATE record is added to the 10212 ** session. 10213 ** </ul> 10214 ** 10215 ** To clarify, if this function is called and then a changeset constructed 10216 ** using [sqlite3session_changeset()], then after applying that changeset to 10217 ** database zFrom the contents of the two compatible tables would be 10218 ** identical. 10219 ** 10220 ** It an error if database zFrom does not exist or does not contain the 10221 ** required compatible table. 10222 ** 10223 ** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite 10224 ** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg 10225 ** may be set to point to a buffer containing an English language error 10226 ** message. It is the responsibility of the caller to free this buffer using 10227 ** sqlite3_free(). 10228 */ 10229 SQLITE_API int sqlite3session_diff( 10230 sqlite3_session *pSession, 10231 const char *zFromDb, 10232 const char *zTbl, 10233 char **pzErrMsg 10234 ); 10235 10236 10237 /* 10238 ** CAPI3REF: Generate A Patchset From A Session Object 10239 ** METHOD: sqlite3_session 10240 ** 10241 ** The differences between a patchset and a changeset are that: 10242 ** 10243 ** <ul> 10244 ** <li> DELETE records consist of the primary key fields only. The 10245 ** original values of other fields are omitted. 10246 ** <li> The original values of any modified fields are omitted from 10247 ** UPDATE records. 10248 ** </ul> 10249 ** 10250 ** A patchset blob may be used with up to date versions of all 10251 ** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(), 10252 ** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly, 10253 ** attempting to use a patchset blob with old versions of the 10254 ** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error. 10255 ** 10256 ** Because the non-primary key "old.*" fields are omitted, no 10257 ** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset 10258 ** is passed to the sqlite3changeset_apply() API. Other conflict types work 10259 ** in the same way as for changesets. 10260 ** 10261 ** Changes within a patchset are ordered in the same way as for changesets 10262 ** generated by the sqlite3session_changeset() function (i.e. all changes for 10263 ** a single table are grouped together, tables appear in the order in which 10264 ** they were attached to the session object). 10265 */ 10266 SQLITE_API int sqlite3session_patchset( 10267 sqlite3_session *pSession, /* Session object */ 10268 int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */ 10269 void **ppPatchset /* OUT: Buffer containing patchset */ 10270 ); 10271 10272 /* 10273 ** CAPI3REF: Test if a changeset has recorded any changes. 10274 ** 10275 ** Return non-zero if no changes to attached tables have been recorded by 10276 ** the session object passed as the first argument. Otherwise, if one or 10277 ** more changes have been recorded, return zero. 10278 ** 10279 ** Even if this function returns zero, it is possible that calling 10280 ** [sqlite3session_changeset()] on the session handle may still return a 10281 ** changeset that contains no changes. This can happen when a row in 10282 ** an attached table is modified and then later on the original values 10283 ** are restored. However, if this function returns non-zero, then it is 10284 ** guaranteed that a call to sqlite3session_changeset() will return a 10285 ** changeset containing zero changes. 10286 */ 10287 SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession); 10288 10289 /* 10290 ** CAPI3REF: Create An Iterator To Traverse A Changeset 10291 ** CONSTRUCTOR: sqlite3_changeset_iter 10292 ** 10293 ** Create an iterator used to iterate through the contents of a changeset. 10294 ** If successful, *pp is set to point to the iterator handle and SQLITE_OK 10295 ** is returned. Otherwise, if an error occurs, *pp is set to zero and an 10296 ** SQLite error code is returned. 10297 ** 10298 ** The following functions can be used to advance and query a changeset 10299 ** iterator created by this function: 10300 ** 10301 ** <ul> 10302 ** <li> [sqlite3changeset_next()] 10303 ** <li> [sqlite3changeset_op()] 10304 ** <li> [sqlite3changeset_new()] 10305 ** <li> [sqlite3changeset_old()] 10306 ** </ul> 10307 ** 10308 ** It is the responsibility of the caller to eventually destroy the iterator 10309 ** by passing it to [sqlite3changeset_finalize()]. The buffer containing the 10310 ** changeset (pChangeset) must remain valid until after the iterator is 10311 ** destroyed. 10312 ** 10313 ** Assuming the changeset blob was created by one of the 10314 ** [sqlite3session_changeset()], [sqlite3changeset_concat()] or 10315 ** [sqlite3changeset_invert()] functions, all changes within the changeset 10316 ** that apply to a single table are grouped together. This means that when 10317 ** an application iterates through a changeset using an iterator created by 10318 ** this function, all changes that relate to a single table are visited 10319 ** consecutively. There is no chance that the iterator will visit a change 10320 ** the applies to table X, then one for table Y, and then later on visit 10321 ** another change for table X. 10322 ** 10323 ** The behavior of sqlite3changeset_start_v2() and its streaming equivalent 10324 ** may be modified by passing a combination of 10325 ** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter. 10326 ** 10327 ** Note that the sqlite3changeset_start_v2() API is still <b>experimental</b> 10328 ** and therefore subject to change. 10329 */ 10330 SQLITE_API int sqlite3changeset_start( 10331 sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ 10332 int nChangeset, /* Size of changeset blob in bytes */ 10333 void *pChangeset /* Pointer to blob containing changeset */ 10334 ); 10335 SQLITE_API int sqlite3changeset_start_v2( 10336 sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ 10337 int nChangeset, /* Size of changeset blob in bytes */ 10338 void *pChangeset, /* Pointer to blob containing changeset */ 10339 int flags /* SESSION_CHANGESETSTART_* flags */ 10340 ); 10341 10342 /* 10343 ** CAPI3REF: Flags for sqlite3changeset_start_v2 10344 ** 10345 ** The following flags may passed via the 4th parameter to 10346 ** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]: 10347 ** 10348 ** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd> 10349 ** Invert the changeset while iterating through it. This is equivalent to 10350 ** inverting a changeset using sqlite3changeset_invert() before applying it. 10351 ** It is an error to specify this flag with a patchset. 10352 */ 10353 #define SQLITE_CHANGESETSTART_INVERT 0x0002 10354 10355 10356 /* 10357 ** CAPI3REF: Advance A Changeset Iterator 10358 ** METHOD: sqlite3_changeset_iter 10359 ** 10360 ** This function may only be used with iterators created by the function 10361 ** [sqlite3changeset_start()]. If it is called on an iterator passed to 10362 ** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE 10363 ** is returned and the call has no effect. 10364 ** 10365 ** Immediately after an iterator is created by sqlite3changeset_start(), it 10366 ** does not point to any change in the changeset. Assuming the changeset 10367 ** is not empty, the first call to this function advances the iterator to 10368 ** point to the first change in the changeset. Each subsequent call advances 10369 ** the iterator to point to the next change in the changeset (if any). If 10370 ** no error occurs and the iterator points to a valid change after a call 10371 ** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned. 10372 ** Otherwise, if all changes in the changeset have already been visited, 10373 ** SQLITE_DONE is returned. 10374 ** 10375 ** If an error occurs, an SQLite error code is returned. Possible error 10376 ** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or 10377 ** SQLITE_NOMEM. 10378 */ 10379 SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter); 10380 10381 /* 10382 ** CAPI3REF: Obtain The Current Operation From A Changeset Iterator 10383 ** METHOD: sqlite3_changeset_iter 10384 ** 10385 ** The pIter argument passed to this function may either be an iterator 10386 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 10387 ** created by [sqlite3changeset_start()]. In the latter case, the most recent 10388 ** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this 10389 ** is not the case, this function returns [SQLITE_MISUSE]. 10390 ** 10391 ** If argument pzTab is not NULL, then *pzTab is set to point to a 10392 ** nul-terminated utf-8 encoded string containing the name of the table 10393 ** affected by the current change. The buffer remains valid until either 10394 ** sqlite3changeset_next() is called on the iterator or until the 10395 ** conflict-handler function returns. If pnCol is not NULL, then *pnCol is 10396 ** set to the number of columns in the table affected by the change. If 10397 ** pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change 10398 ** is an indirect change, or false (0) otherwise. See the documentation for 10399 ** [sqlite3session_indirect()] for a description of direct and indirect 10400 ** changes. Finally, if pOp is not NULL, then *pOp is set to one of 10401 ** [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], depending on the 10402 ** type of change that the iterator currently points to. 10403 ** 10404 ** If no error occurs, SQLITE_OK is returned. If an error does occur, an 10405 ** SQLite error code is returned. The values of the output variables may not 10406 ** be trusted in this case. 10407 */ 10408 SQLITE_API int sqlite3changeset_op( 10409 sqlite3_changeset_iter *pIter, /* Iterator object */ 10410 const char **pzTab, /* OUT: Pointer to table name */ 10411 int *pnCol, /* OUT: Number of columns in table */ 10412 int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */ 10413 int *pbIndirect /* OUT: True for an 'indirect' change */ 10414 ); 10415 10416 /* 10417 ** CAPI3REF: Obtain The Primary Key Definition Of A Table 10418 ** METHOD: sqlite3_changeset_iter 10419 ** 10420 ** For each modified table, a changeset includes the following: 10421 ** 10422 ** <ul> 10423 ** <li> The number of columns in the table, and 10424 ** <li> Which of those columns make up the tables PRIMARY KEY. 10425 ** </ul> 10426 ** 10427 ** This function is used to find which columns comprise the PRIMARY KEY of 10428 ** the table modified by the change that iterator pIter currently points to. 10429 ** If successful, *pabPK is set to point to an array of nCol entries, where 10430 ** nCol is the number of columns in the table. Elements of *pabPK are set to 10431 ** 0x01 if the corresponding column is part of the tables primary key, or 10432 ** 0x00 if it is not. 10433 ** 10434 ** If argument pnCol is not NULL, then *pnCol is set to the number of columns 10435 ** in the table. 10436 ** 10437 ** If this function is called when the iterator does not point to a valid 10438 ** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise, 10439 ** SQLITE_OK is returned and the output variables populated as described 10440 ** above. 10441 */ 10442 SQLITE_API int sqlite3changeset_pk( 10443 sqlite3_changeset_iter *pIter, /* Iterator object */ 10444 unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */ 10445 int *pnCol /* OUT: Number of entries in output array */ 10446 ); 10447 10448 /* 10449 ** CAPI3REF: Obtain old.* Values From A Changeset Iterator 10450 ** METHOD: sqlite3_changeset_iter 10451 ** 10452 ** The pIter argument passed to this function may either be an iterator 10453 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 10454 ** created by [sqlite3changeset_start()]. In the latter case, the most recent 10455 ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. 10456 ** Furthermore, it may only be called if the type of change that the iterator 10457 ** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise, 10458 ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. 10459 ** 10460 ** Argument iVal must be greater than or equal to 0, and less than the number 10461 ** of columns in the table affected by the current change. Otherwise, 10462 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 10463 ** 10464 ** If successful, this function sets *ppValue to point to a protected 10465 ** sqlite3_value object containing the iVal'th value from the vector of 10466 ** original row values stored as part of the UPDATE or DELETE change and 10467 ** returns SQLITE_OK. The name of the function comes from the fact that this 10468 ** is similar to the "old.*" columns available to update or delete triggers. 10469 ** 10470 ** If some other error occurs (e.g. an OOM condition), an SQLite error code 10471 ** is returned and *ppValue is set to NULL. 10472 */ 10473 SQLITE_API int sqlite3changeset_old( 10474 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 10475 int iVal, /* Column number */ 10476 sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */ 10477 ); 10478 10479 /* 10480 ** CAPI3REF: Obtain new.* Values From A Changeset Iterator 10481 ** METHOD: sqlite3_changeset_iter 10482 ** 10483 ** The pIter argument passed to this function may either be an iterator 10484 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 10485 ** created by [sqlite3changeset_start()]. In the latter case, the most recent 10486 ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. 10487 ** Furthermore, it may only be called if the type of change that the iterator 10488 ** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise, 10489 ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. 10490 ** 10491 ** Argument iVal must be greater than or equal to 0, and less than the number 10492 ** of columns in the table affected by the current change. Otherwise, 10493 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 10494 ** 10495 ** If successful, this function sets *ppValue to point to a protected 10496 ** sqlite3_value object containing the iVal'th value from the vector of 10497 ** new row values stored as part of the UPDATE or INSERT change and 10498 ** returns SQLITE_OK. If the change is an UPDATE and does not include 10499 ** a new value for the requested column, *ppValue is set to NULL and 10500 ** SQLITE_OK returned. The name of the function comes from the fact that 10501 ** this is similar to the "new.*" columns available to update or delete 10502 ** triggers. 10503 ** 10504 ** If some other error occurs (e.g. an OOM condition), an SQLite error code 10505 ** is returned and *ppValue is set to NULL. 10506 */ 10507 SQLITE_API int sqlite3changeset_new( 10508 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 10509 int iVal, /* Column number */ 10510 sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */ 10511 ); 10512 10513 /* 10514 ** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator 10515 ** METHOD: sqlite3_changeset_iter 10516 ** 10517 ** This function should only be used with iterator objects passed to a 10518 ** conflict-handler callback by [sqlite3changeset_apply()] with either 10519 ** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function 10520 ** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue 10521 ** is set to NULL. 10522 ** 10523 ** Argument iVal must be greater than or equal to 0, and less than the number 10524 ** of columns in the table affected by the current change. Otherwise, 10525 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 10526 ** 10527 ** If successful, this function sets *ppValue to point to a protected 10528 ** sqlite3_value object containing the iVal'th value from the 10529 ** "conflicting row" associated with the current conflict-handler callback 10530 ** and returns SQLITE_OK. 10531 ** 10532 ** If some other error occurs (e.g. an OOM condition), an SQLite error code 10533 ** is returned and *ppValue is set to NULL. 10534 */ 10535 SQLITE_API int sqlite3changeset_conflict( 10536 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 10537 int iVal, /* Column number */ 10538 sqlite3_value **ppValue /* OUT: Value from conflicting row */ 10539 ); 10540 10541 /* 10542 ** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations 10543 ** METHOD: sqlite3_changeset_iter 10544 ** 10545 ** This function may only be called with an iterator passed to an 10546 ** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case 10547 ** it sets the output variable to the total number of known foreign key 10548 ** violations in the destination database and returns SQLITE_OK. 10549 ** 10550 ** In all other cases this function returns SQLITE_MISUSE. 10551 */ 10552 SQLITE_API int sqlite3changeset_fk_conflicts( 10553 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 10554 int *pnOut /* OUT: Number of FK violations */ 10555 ); 10556 10557 10558 /* 10559 ** CAPI3REF: Finalize A Changeset Iterator 10560 ** METHOD: sqlite3_changeset_iter 10561 ** 10562 ** This function is used to finalize an iterator allocated with 10563 ** [sqlite3changeset_start()]. 10564 ** 10565 ** This function should only be called on iterators created using the 10566 ** [sqlite3changeset_start()] function. If an application calls this 10567 ** function with an iterator passed to a conflict-handler by 10568 ** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the 10569 ** call has no effect. 10570 ** 10571 ** If an error was encountered within a call to an sqlite3changeset_xxx() 10572 ** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an 10573 ** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding 10574 ** to that error is returned by this function. Otherwise, SQLITE_OK is 10575 ** returned. This is to allow the following pattern (pseudo-code): 10576 ** 10577 ** <pre> 10578 ** sqlite3changeset_start(); 10579 ** while( SQLITE_ROW==sqlite3changeset_next() ){ 10580 ** // Do something with change. 10581 ** } 10582 ** rc = sqlite3changeset_finalize(); 10583 ** if( rc!=SQLITE_OK ){ 10584 ** // An error has occurred 10585 ** } 10586 ** </pre> 10587 */ 10588 SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter); 10589 10590 /* 10591 ** CAPI3REF: Invert A Changeset 10592 ** 10593 ** This function is used to "invert" a changeset object. Applying an inverted 10594 ** changeset to a database reverses the effects of applying the uninverted 10595 ** changeset. Specifically: 10596 ** 10597 ** <ul> 10598 ** <li> Each DELETE change is changed to an INSERT, and 10599 ** <li> Each INSERT change is changed to a DELETE, and 10600 ** <li> For each UPDATE change, the old.* and new.* values are exchanged. 10601 ** </ul> 10602 ** 10603 ** This function does not change the order in which changes appear within 10604 ** the changeset. It merely reverses the sense of each individual change. 10605 ** 10606 ** If successful, a pointer to a buffer containing the inverted changeset 10607 ** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and 10608 ** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are 10609 ** zeroed and an SQLite error code returned. 10610 ** 10611 ** It is the responsibility of the caller to eventually call sqlite3_free() 10612 ** on the *ppOut pointer to free the buffer allocation following a successful 10613 ** call to this function. 10614 ** 10615 ** WARNING/TODO: This function currently assumes that the input is a valid 10616 ** changeset. If it is not, the results are undefined. 10617 */ 10618 SQLITE_API int sqlite3changeset_invert( 10619 int nIn, const void *pIn, /* Input changeset */ 10620 int *pnOut, void **ppOut /* OUT: Inverse of input */ 10621 ); 10622 10623 /* 10624 ** CAPI3REF: Concatenate Two Changeset Objects 10625 ** 10626 ** This function is used to concatenate two changesets, A and B, into a 10627 ** single changeset. The result is a changeset equivalent to applying 10628 ** changeset A followed by changeset B. 10629 ** 10630 ** This function combines the two input changesets using an 10631 ** sqlite3_changegroup object. Calling it produces similar results as the 10632 ** following code fragment: 10633 ** 10634 ** <pre> 10635 ** sqlite3_changegroup *pGrp; 10636 ** rc = sqlite3_changegroup_new(&pGrp); 10637 ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA); 10638 ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB); 10639 ** if( rc==SQLITE_OK ){ 10640 ** rc = sqlite3changegroup_output(pGrp, pnOut, ppOut); 10641 ** }else{ 10642 ** *ppOut = 0; 10643 ** *pnOut = 0; 10644 ** } 10645 ** </pre> 10646 ** 10647 ** Refer to the sqlite3_changegroup documentation below for details. 10648 */ 10649 SQLITE_API int sqlite3changeset_concat( 10650 int nA, /* Number of bytes in buffer pA */ 10651 void *pA, /* Pointer to buffer containing changeset A */ 10652 int nB, /* Number of bytes in buffer pB */ 10653 void *pB, /* Pointer to buffer containing changeset B */ 10654 int *pnOut, /* OUT: Number of bytes in output changeset */ 10655 void **ppOut /* OUT: Buffer containing output changeset */ 10656 ); 10657 10658 10659 /* 10660 ** CAPI3REF: Changegroup Handle 10661 ** 10662 ** A changegroup is an object used to combine two or more 10663 ** [changesets] or [patchsets] 10664 */ 10665 typedef struct sqlite3_changegroup sqlite3_changegroup; 10666 10667 /* 10668 ** CAPI3REF: Create A New Changegroup Object 10669 ** CONSTRUCTOR: sqlite3_changegroup 10670 ** 10671 ** An sqlite3_changegroup object is used to combine two or more changesets 10672 ** (or patchsets) into a single changeset (or patchset). A single changegroup 10673 ** object may combine changesets or patchsets, but not both. The output is 10674 ** always in the same format as the input. 10675 ** 10676 ** If successful, this function returns SQLITE_OK and populates (*pp) with 10677 ** a pointer to a new sqlite3_changegroup object before returning. The caller 10678 ** should eventually free the returned object using a call to 10679 ** sqlite3changegroup_delete(). If an error occurs, an SQLite error code 10680 ** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL. 10681 ** 10682 ** The usual usage pattern for an sqlite3_changegroup object is as follows: 10683 ** 10684 ** <ul> 10685 ** <li> It is created using a call to sqlite3changegroup_new(). 10686 ** 10687 ** <li> Zero or more changesets (or patchsets) are added to the object 10688 ** by calling sqlite3changegroup_add(). 10689 ** 10690 ** <li> The result of combining all input changesets together is obtained 10691 ** by the application via a call to sqlite3changegroup_output(). 10692 ** 10693 ** <li> The object is deleted using a call to sqlite3changegroup_delete(). 10694 ** </ul> 10695 ** 10696 ** Any number of calls to add() and output() may be made between the calls to 10697 ** new() and delete(), and in any order. 10698 ** 10699 ** As well as the regular sqlite3changegroup_add() and 10700 ** sqlite3changegroup_output() functions, also available are the streaming 10701 ** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm(). 10702 */ 10703 SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp); 10704 10705 /* 10706 ** CAPI3REF: Add A Changeset To A Changegroup 10707 ** METHOD: sqlite3_changegroup 10708 ** 10709 ** Add all changes within the changeset (or patchset) in buffer pData (size 10710 ** nData bytes) to the changegroup. 10711 ** 10712 ** If the buffer contains a patchset, then all prior calls to this function 10713 ** on the same changegroup object must also have specified patchsets. Or, if 10714 ** the buffer contains a changeset, so must have the earlier calls to this 10715 ** function. Otherwise, SQLITE_ERROR is returned and no changes are added 10716 ** to the changegroup. 10717 ** 10718 ** Rows within the changeset and changegroup are identified by the values in 10719 ** their PRIMARY KEY columns. A change in the changeset is considered to 10720 ** apply to the same row as a change already present in the changegroup if 10721 ** the two rows have the same primary key. 10722 ** 10723 ** Changes to rows that do not already appear in the changegroup are 10724 ** simply copied into it. Or, if both the new changeset and the changegroup 10725 ** contain changes that apply to a single row, the final contents of the 10726 ** changegroup depends on the type of each change, as follows: 10727 ** 10728 ** <table border=1 style="margin-left:8ex;margin-right:8ex"> 10729 ** <tr><th style="white-space:pre">Existing Change </th> 10730 ** <th style="white-space:pre">New Change </th> 10731 ** <th>Output Change 10732 ** <tr><td>INSERT <td>INSERT <td> 10733 ** The new change is ignored. This case does not occur if the new 10734 ** changeset was recorded immediately after the changesets already 10735 ** added to the changegroup. 10736 ** <tr><td>INSERT <td>UPDATE <td> 10737 ** The INSERT change remains in the changegroup. The values in the 10738 ** INSERT change are modified as if the row was inserted by the 10739 ** existing change and then updated according to the new change. 10740 ** <tr><td>INSERT <td>DELETE <td> 10741 ** The existing INSERT is removed from the changegroup. The DELETE is 10742 ** not added. 10743 ** <tr><td>UPDATE <td>INSERT <td> 10744 ** The new change is ignored. This case does not occur if the new 10745 ** changeset was recorded immediately after the changesets already 10746 ** added to the changegroup. 10747 ** <tr><td>UPDATE <td>UPDATE <td> 10748 ** The existing UPDATE remains within the changegroup. It is amended 10749 ** so that the accompanying values are as if the row was updated once 10750 ** by the existing change and then again by the new change. 10751 ** <tr><td>UPDATE <td>DELETE <td> 10752 ** The existing UPDATE is replaced by the new DELETE within the 10753 ** changegroup. 10754 ** <tr><td>DELETE <td>INSERT <td> 10755 ** If one or more of the column values in the row inserted by the 10756 ** new change differ from those in the row deleted by the existing 10757 ** change, the existing DELETE is replaced by an UPDATE within the 10758 ** changegroup. Otherwise, if the inserted row is exactly the same 10759 ** as the deleted row, the existing DELETE is simply discarded. 10760 ** <tr><td>DELETE <td>UPDATE <td> 10761 ** The new change is ignored. This case does not occur if the new 10762 ** changeset was recorded immediately after the changesets already 10763 ** added to the changegroup. 10764 ** <tr><td>DELETE <td>DELETE <td> 10765 ** The new change is ignored. This case does not occur if the new 10766 ** changeset was recorded immediately after the changesets already 10767 ** added to the changegroup. 10768 ** </table> 10769 ** 10770 ** If the new changeset contains changes to a table that is already present 10771 ** in the changegroup, then the number of columns and the position of the 10772 ** primary key columns for the table must be consistent. If this is not the 10773 ** case, this function fails with SQLITE_SCHEMA. If the input changeset 10774 ** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is 10775 ** returned. Or, if an out-of-memory condition occurs during processing, this 10776 ** function returns SQLITE_NOMEM. In all cases, if an error occurs the state 10777 ** of the final contents of the changegroup is undefined. 10778 ** 10779 ** If no error occurs, SQLITE_OK is returned. 10780 */ 10781 SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData); 10782 10783 /* 10784 ** CAPI3REF: Obtain A Composite Changeset From A Changegroup 10785 ** METHOD: sqlite3_changegroup 10786 ** 10787 ** Obtain a buffer containing a changeset (or patchset) representing the 10788 ** current contents of the changegroup. If the inputs to the changegroup 10789 ** were themselves changesets, the output is a changeset. Or, if the 10790 ** inputs were patchsets, the output is also a patchset. 10791 ** 10792 ** As with the output of the sqlite3session_changeset() and 10793 ** sqlite3session_patchset() functions, all changes related to a single 10794 ** table are grouped together in the output of this function. Tables appear 10795 ** in the same order as for the very first changeset added to the changegroup. 10796 ** If the second or subsequent changesets added to the changegroup contain 10797 ** changes for tables that do not appear in the first changeset, they are 10798 ** appended onto the end of the output changeset, again in the order in 10799 ** which they are first encountered. 10800 ** 10801 ** If an error occurs, an SQLite error code is returned and the output 10802 ** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK 10803 ** is returned and the output variables are set to the size of and a 10804 ** pointer to the output buffer, respectively. In this case it is the 10805 ** responsibility of the caller to eventually free the buffer using a 10806 ** call to sqlite3_free(). 10807 */ 10808 SQLITE_API int sqlite3changegroup_output( 10809 sqlite3_changegroup*, 10810 int *pnData, /* OUT: Size of output buffer in bytes */ 10811 void **ppData /* OUT: Pointer to output buffer */ 10812 ); 10813 10814 /* 10815 ** CAPI3REF: Delete A Changegroup Object 10816 ** DESTRUCTOR: sqlite3_changegroup 10817 */ 10818 SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*); 10819 10820 /* 10821 ** CAPI3REF: Apply A Changeset To A Database 10822 ** 10823 ** Apply a changeset or patchset to a database. These functions attempt to 10824 ** update the "main" database attached to handle db with the changes found in 10825 ** the changeset passed via the second and third arguments. 10826 ** 10827 ** The fourth argument (xFilter) passed to these functions is the "filter 10828 ** callback". If it is not NULL, then for each table affected by at least one 10829 ** change in the changeset, the filter callback is invoked with 10830 ** the table name as the second argument, and a copy of the context pointer 10831 ** passed as the sixth argument as the first. If the "filter callback" 10832 ** returns zero, then no attempt is made to apply any changes to the table. 10833 ** Otherwise, if the return value is non-zero or the xFilter argument to 10834 ** is NULL, all changes related to the table are attempted. 10835 ** 10836 ** For each table that is not excluded by the filter callback, this function 10837 ** tests that the target database contains a compatible table. A table is 10838 ** considered compatible if all of the following are true: 10839 ** 10840 ** <ul> 10841 ** <li> The table has the same name as the name recorded in the 10842 ** changeset, and 10843 ** <li> The table has at least as many columns as recorded in the 10844 ** changeset, and 10845 ** <li> The table has primary key columns in the same position as 10846 ** recorded in the changeset. 10847 ** </ul> 10848 ** 10849 ** If there is no compatible table, it is not an error, but none of the 10850 ** changes associated with the table are applied. A warning message is issued 10851 ** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most 10852 ** one such warning is issued for each table in the changeset. 10853 ** 10854 ** For each change for which there is a compatible table, an attempt is made 10855 ** to modify the table contents according to the UPDATE, INSERT or DELETE 10856 ** change. If a change cannot be applied cleanly, the conflict handler 10857 ** function passed as the fifth argument to sqlite3changeset_apply() may be 10858 ** invoked. A description of exactly when the conflict handler is invoked for 10859 ** each type of change is below. 10860 ** 10861 ** Unlike the xFilter argument, xConflict may not be passed NULL. The results 10862 ** of passing anything other than a valid function pointer as the xConflict 10863 ** argument are undefined. 10864 ** 10865 ** Each time the conflict handler function is invoked, it must return one 10866 ** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or 10867 ** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned 10868 ** if the second argument passed to the conflict handler is either 10869 ** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler 10870 ** returns an illegal value, any changes already made are rolled back and 10871 ** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different 10872 ** actions are taken by sqlite3changeset_apply() depending on the value 10873 ** returned by each invocation of the conflict-handler function. Refer to 10874 ** the documentation for the three 10875 ** [SQLITE_CHANGESET_OMIT|available return values] for details. 10876 ** 10877 ** <dl> 10878 ** <dt>DELETE Changes<dd> 10879 ** For each DELETE change, the function checks if the target database 10880 ** contains a row with the same primary key value (or values) as the 10881 ** original row values stored in the changeset. If it does, and the values 10882 ** stored in all non-primary key columns also match the values stored in 10883 ** the changeset the row is deleted from the target database. 10884 ** 10885 ** If a row with matching primary key values is found, but one or more of 10886 ** the non-primary key fields contains a value different from the original 10887 ** row value stored in the changeset, the conflict-handler function is 10888 ** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the 10889 ** database table has more columns than are recorded in the changeset, 10890 ** only the values of those non-primary key fields are compared against 10891 ** the current database contents - any trailing database table columns 10892 ** are ignored. 10893 ** 10894 ** If no row with matching primary key values is found in the database, 10895 ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] 10896 ** passed as the second argument. 10897 ** 10898 ** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT 10899 ** (which can only happen if a foreign key constraint is violated), the 10900 ** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT] 10901 ** passed as the second argument. This includes the case where the DELETE 10902 ** operation is attempted because an earlier call to the conflict handler 10903 ** function returned [SQLITE_CHANGESET_REPLACE]. 10904 ** 10905 ** <dt>INSERT Changes<dd> 10906 ** For each INSERT change, an attempt is made to insert the new row into 10907 ** the database. If the changeset row contains fewer fields than the 10908 ** database table, the trailing fields are populated with their default 10909 ** values. 10910 ** 10911 ** If the attempt to insert the row fails because the database already 10912 ** contains a row with the same primary key values, the conflict handler 10913 ** function is invoked with the second argument set to 10914 ** [SQLITE_CHANGESET_CONFLICT]. 10915 ** 10916 ** If the attempt to insert the row fails because of some other constraint 10917 ** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is 10918 ** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT]. 10919 ** This includes the case where the INSERT operation is re-attempted because 10920 ** an earlier call to the conflict handler function returned 10921 ** [SQLITE_CHANGESET_REPLACE]. 10922 ** 10923 ** <dt>UPDATE Changes<dd> 10924 ** For each UPDATE change, the function checks if the target database 10925 ** contains a row with the same primary key value (or values) as the 10926 ** original row values stored in the changeset. If it does, and the values 10927 ** stored in all modified non-primary key columns also match the values 10928 ** stored in the changeset the row is updated within the target database. 10929 ** 10930 ** If a row with matching primary key values is found, but one or more of 10931 ** the modified non-primary key fields contains a value different from an 10932 ** original row value stored in the changeset, the conflict-handler function 10933 ** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since 10934 ** UPDATE changes only contain values for non-primary key fields that are 10935 ** to be modified, only those fields need to match the original values to 10936 ** avoid the SQLITE_CHANGESET_DATA conflict-handler callback. 10937 ** 10938 ** If no row with matching primary key values is found in the database, 10939 ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] 10940 ** passed as the second argument. 10941 ** 10942 ** If the UPDATE operation is attempted, but SQLite returns 10943 ** SQLITE_CONSTRAINT, the conflict-handler function is invoked with 10944 ** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument. 10945 ** This includes the case where the UPDATE operation is attempted after 10946 ** an earlier call to the conflict handler function returned 10947 ** [SQLITE_CHANGESET_REPLACE]. 10948 ** </dl> 10949 ** 10950 ** It is safe to execute SQL statements, including those that write to the 10951 ** table that the callback related to, from within the xConflict callback. 10952 ** This can be used to further customize the application's conflict 10953 ** resolution strategy. 10954 ** 10955 ** All changes made by these functions are enclosed in a savepoint transaction. 10956 ** If any other error (aside from a constraint failure when attempting to 10957 ** write to the target database) occurs, then the savepoint transaction is 10958 ** rolled back, restoring the target database to its original state, and an 10959 ** SQLite error code returned. 10960 ** 10961 ** If the output parameters (ppRebase) and (pnRebase) are non-NULL and 10962 ** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2() 10963 ** may set (*ppRebase) to point to a "rebase" that may be used with the 10964 ** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase) 10965 ** is set to the size of the buffer in bytes. It is the responsibility of the 10966 ** caller to eventually free any such buffer using sqlite3_free(). The buffer 10967 ** is only allocated and populated if one or more conflicts were encountered 10968 ** while applying the patchset. See comments surrounding the sqlite3_rebaser 10969 ** APIs for further details. 10970 ** 10971 ** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent 10972 ** may be modified by passing a combination of 10973 ** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter. 10974 ** 10975 ** Note that the sqlite3changeset_apply_v2() API is still <b>experimental</b> 10976 ** and therefore subject to change. 10977 */ 10978 SQLITE_API int sqlite3changeset_apply( 10979 sqlite3 *db, /* Apply change to "main" db of this handle */ 10980 int nChangeset, /* Size of changeset in bytes */ 10981 void *pChangeset, /* Changeset blob */ 10982 int(*xFilter)( 10983 void *pCtx, /* Copy of sixth arg to _apply() */ 10984 const char *zTab /* Table name */ 10985 ), 10986 int(*xConflict)( 10987 void *pCtx, /* Copy of sixth arg to _apply() */ 10988 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 10989 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 10990 ), 10991 void *pCtx /* First argument passed to xConflict */ 10992 ); 10993 SQLITE_API int sqlite3changeset_apply_v2( 10994 sqlite3 *db, /* Apply change to "main" db of this handle */ 10995 int nChangeset, /* Size of changeset in bytes */ 10996 void *pChangeset, /* Changeset blob */ 10997 int(*xFilter)( 10998 void *pCtx, /* Copy of sixth arg to _apply() */ 10999 const char *zTab /* Table name */ 11000 ), 11001 int(*xConflict)( 11002 void *pCtx, /* Copy of sixth arg to _apply() */ 11003 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 11004 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 11005 ), 11006 void *pCtx, /* First argument passed to xConflict */ 11007 void **ppRebase, int *pnRebase, /* OUT: Rebase data */ 11008 int flags /* SESSION_CHANGESETAPPLY_* flags */ 11009 ); 11010 11011 /* 11012 ** CAPI3REF: Flags for sqlite3changeset_apply_v2 11013 ** 11014 ** The following flags may passed via the 9th parameter to 11015 ** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]: 11016 ** 11017 ** <dl> 11018 ** <dt>SQLITE_CHANGESETAPPLY_NOSAVEPOINT <dd> 11019 ** Usually, the sessions module encloses all operations performed by 11020 ** a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The 11021 ** SAVEPOINT is committed if the changeset or patchset is successfully 11022 ** applied, or rolled back if an error occurs. Specifying this flag 11023 ** causes the sessions module to omit this savepoint. In this case, if the 11024 ** caller has an open transaction or savepoint when apply_v2() is called, 11025 ** it may revert the partially applied changeset by rolling it back. 11026 ** 11027 ** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd> 11028 ** Invert the changeset before applying it. This is equivalent to inverting 11029 ** a changeset using sqlite3changeset_invert() before applying it. It is 11030 ** an error to specify this flag with a patchset. 11031 */ 11032 #define SQLITE_CHANGESETAPPLY_NOSAVEPOINT 0x0001 11033 #define SQLITE_CHANGESETAPPLY_INVERT 0x0002 11034 11035 /* 11036 ** CAPI3REF: Constants Passed To The Conflict Handler 11037 ** 11038 ** Values that may be passed as the second argument to a conflict-handler. 11039 ** 11040 ** <dl> 11041 ** <dt>SQLITE_CHANGESET_DATA<dd> 11042 ** The conflict handler is invoked with CHANGESET_DATA as the second argument 11043 ** when processing a DELETE or UPDATE change if a row with the required 11044 ** PRIMARY KEY fields is present in the database, but one or more other 11045 ** (non primary-key) fields modified by the update do not contain the 11046 ** expected "before" values. 11047 ** 11048 ** The conflicting row, in this case, is the database row with the matching 11049 ** primary key. 11050 ** 11051 ** <dt>SQLITE_CHANGESET_NOTFOUND<dd> 11052 ** The conflict handler is invoked with CHANGESET_NOTFOUND as the second 11053 ** argument when processing a DELETE or UPDATE change if a row with the 11054 ** required PRIMARY KEY fields is not present in the database. 11055 ** 11056 ** There is no conflicting row in this case. The results of invoking the 11057 ** sqlite3changeset_conflict() API are undefined. 11058 ** 11059 ** <dt>SQLITE_CHANGESET_CONFLICT<dd> 11060 ** CHANGESET_CONFLICT is passed as the second argument to the conflict 11061 ** handler while processing an INSERT change if the operation would result 11062 ** in duplicate primary key values. 11063 ** 11064 ** The conflicting row in this case is the database row with the matching 11065 ** primary key. 11066 ** 11067 ** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd> 11068 ** If foreign key handling is enabled, and applying a changeset leaves the 11069 ** database in a state containing foreign key violations, the conflict 11070 ** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument 11071 ** exactly once before the changeset is committed. If the conflict handler 11072 ** returns CHANGESET_OMIT, the changes, including those that caused the 11073 ** foreign key constraint violation, are committed. Or, if it returns 11074 ** CHANGESET_ABORT, the changeset is rolled back. 11075 ** 11076 ** No current or conflicting row information is provided. The only function 11077 ** it is possible to call on the supplied sqlite3_changeset_iter handle 11078 ** is sqlite3changeset_fk_conflicts(). 11079 ** 11080 ** <dt>SQLITE_CHANGESET_CONSTRAINT<dd> 11081 ** If any other constraint violation occurs while applying a change (i.e. 11082 ** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is 11083 ** invoked with CHANGESET_CONSTRAINT as the second argument. 11084 ** 11085 ** There is no conflicting row in this case. The results of invoking the 11086 ** sqlite3changeset_conflict() API are undefined. 11087 ** 11088 ** </dl> 11089 */ 11090 #define SQLITE_CHANGESET_DATA 1 11091 #define SQLITE_CHANGESET_NOTFOUND 2 11092 #define SQLITE_CHANGESET_CONFLICT 3 11093 #define SQLITE_CHANGESET_CONSTRAINT 4 11094 #define SQLITE_CHANGESET_FOREIGN_KEY 5 11095 11096 /* 11097 ** CAPI3REF: Constants Returned By The Conflict Handler 11098 ** 11099 ** A conflict handler callback must return one of the following three values. 11100 ** 11101 ** <dl> 11102 ** <dt>SQLITE_CHANGESET_OMIT<dd> 11103 ** If a conflict handler returns this value no special action is taken. The 11104 ** change that caused the conflict is not applied. The session module 11105 ** continues to the next change in the changeset. 11106 ** 11107 ** <dt>SQLITE_CHANGESET_REPLACE<dd> 11108 ** This value may only be returned if the second argument to the conflict 11109 ** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this 11110 ** is not the case, any changes applied so far are rolled back and the 11111 ** call to sqlite3changeset_apply() returns SQLITE_MISUSE. 11112 ** 11113 ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict 11114 ** handler, then the conflicting row is either updated or deleted, depending 11115 ** on the type of change. 11116 ** 11117 ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict 11118 ** handler, then the conflicting row is removed from the database and a 11119 ** second attempt to apply the change is made. If this second attempt fails, 11120 ** the original row is restored to the database before continuing. 11121 ** 11122 ** <dt>SQLITE_CHANGESET_ABORT<dd> 11123 ** If this value is returned, any changes applied so far are rolled back 11124 ** and the call to sqlite3changeset_apply() returns SQLITE_ABORT. 11125 ** </dl> 11126 */ 11127 #define SQLITE_CHANGESET_OMIT 0 11128 #define SQLITE_CHANGESET_REPLACE 1 11129 #define SQLITE_CHANGESET_ABORT 2 11130 11131 /* 11132 ** CAPI3REF: Rebasing changesets 11133 ** EXPERIMENTAL 11134 ** 11135 ** Suppose there is a site hosting a database in state S0. And that 11136 ** modifications are made that move that database to state S1 and a 11137 ** changeset recorded (the "local" changeset). Then, a changeset based 11138 ** on S0 is received from another site (the "remote" changeset) and 11139 ** applied to the database. The database is then in state 11140 ** (S1+"remote"), where the exact state depends on any conflict 11141 ** resolution decisions (OMIT or REPLACE) made while applying "remote". 11142 ** Rebasing a changeset is to update it to take those conflict 11143 ** resolution decisions into account, so that the same conflicts 11144 ** do not have to be resolved elsewhere in the network. 11145 ** 11146 ** For example, if both the local and remote changesets contain an 11147 ** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)": 11148 ** 11149 ** local: INSERT INTO t1 VALUES(1, 'v1'); 11150 ** remote: INSERT INTO t1 VALUES(1, 'v2'); 11151 ** 11152 ** and the conflict resolution is REPLACE, then the INSERT change is 11153 ** removed from the local changeset (it was overridden). Or, if the 11154 ** conflict resolution was "OMIT", then the local changeset is modified 11155 ** to instead contain: 11156 ** 11157 ** UPDATE t1 SET b = 'v2' WHERE a=1; 11158 ** 11159 ** Changes within the local changeset are rebased as follows: 11160 ** 11161 ** <dl> 11162 ** <dt>Local INSERT<dd> 11163 ** This may only conflict with a remote INSERT. If the conflict 11164 ** resolution was OMIT, then add an UPDATE change to the rebased 11165 ** changeset. Or, if the conflict resolution was REPLACE, add 11166 ** nothing to the rebased changeset. 11167 ** 11168 ** <dt>Local DELETE<dd> 11169 ** This may conflict with a remote UPDATE or DELETE. In both cases the 11170 ** only possible resolution is OMIT. If the remote operation was a 11171 ** DELETE, then add no change to the rebased changeset. If the remote 11172 ** operation was an UPDATE, then the old.* fields of change are updated 11173 ** to reflect the new.* values in the UPDATE. 11174 ** 11175 ** <dt>Local UPDATE<dd> 11176 ** This may conflict with a remote UPDATE or DELETE. If it conflicts 11177 ** with a DELETE, and the conflict resolution was OMIT, then the update 11178 ** is changed into an INSERT. Any undefined values in the new.* record 11179 ** from the update change are filled in using the old.* values from 11180 ** the conflicting DELETE. Or, if the conflict resolution was REPLACE, 11181 ** the UPDATE change is simply omitted from the rebased changeset. 11182 ** 11183 ** If conflict is with a remote UPDATE and the resolution is OMIT, then 11184 ** the old.* values are rebased using the new.* values in the remote 11185 ** change. Or, if the resolution is REPLACE, then the change is copied 11186 ** into the rebased changeset with updates to columns also updated by 11187 ** the conflicting remote UPDATE removed. If this means no columns would 11188 ** be updated, the change is omitted. 11189 ** </dl> 11190 ** 11191 ** A local change may be rebased against multiple remote changes 11192 ** simultaneously. If a single key is modified by multiple remote 11193 ** changesets, they are combined as follows before the local changeset 11194 ** is rebased: 11195 ** 11196 ** <ul> 11197 ** <li> If there has been one or more REPLACE resolutions on a 11198 ** key, it is rebased according to a REPLACE. 11199 ** 11200 ** <li> If there have been no REPLACE resolutions on a key, then 11201 ** the local changeset is rebased according to the most recent 11202 ** of the OMIT resolutions. 11203 ** </ul> 11204 ** 11205 ** Note that conflict resolutions from multiple remote changesets are 11206 ** combined on a per-field basis, not per-row. This means that in the 11207 ** case of multiple remote UPDATE operations, some fields of a single 11208 ** local change may be rebased for REPLACE while others are rebased for 11209 ** OMIT. 11210 ** 11211 ** In order to rebase a local changeset, the remote changeset must first 11212 ** be applied to the local database using sqlite3changeset_apply_v2() and 11213 ** the buffer of rebase information captured. Then: 11214 ** 11215 ** <ol> 11216 ** <li> An sqlite3_rebaser object is created by calling 11217 ** sqlite3rebaser_create(). 11218 ** <li> The new object is configured with the rebase buffer obtained from 11219 ** sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure(). 11220 ** If the local changeset is to be rebased against multiple remote 11221 ** changesets, then sqlite3rebaser_configure() should be called 11222 ** multiple times, in the same order that the multiple 11223 ** sqlite3changeset_apply_v2() calls were made. 11224 ** <li> Each local changeset is rebased by calling sqlite3rebaser_rebase(). 11225 ** <li> The sqlite3_rebaser object is deleted by calling 11226 ** sqlite3rebaser_delete(). 11227 ** </ol> 11228 */ 11229 typedef struct sqlite3_rebaser sqlite3_rebaser; 11230 11231 /* 11232 ** CAPI3REF: Create a changeset rebaser object. 11233 ** EXPERIMENTAL 11234 ** 11235 ** Allocate a new changeset rebaser object. If successful, set (*ppNew) to 11236 ** point to the new object and return SQLITE_OK. Otherwise, if an error 11237 ** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew) 11238 ** to NULL. 11239 */ 11240 SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew); 11241 11242 /* 11243 ** CAPI3REF: Configure a changeset rebaser object. 11244 ** EXPERIMENTAL 11245 ** 11246 ** Configure the changeset rebaser object to rebase changesets according 11247 ** to the conflict resolutions described by buffer pRebase (size nRebase 11248 ** bytes), which must have been obtained from a previous call to 11249 ** sqlite3changeset_apply_v2(). 11250 */ 11251 SQLITE_API int sqlite3rebaser_configure( 11252 sqlite3_rebaser*, 11253 int nRebase, const void *pRebase 11254 ); 11255 11256 /* 11257 ** CAPI3REF: Rebase a changeset 11258 ** EXPERIMENTAL 11259 ** 11260 ** Argument pIn must point to a buffer containing a changeset nIn bytes 11261 ** in size. This function allocates and populates a buffer with a copy 11262 ** of the changeset rebased according to the configuration of the 11263 ** rebaser object passed as the first argument. If successful, (*ppOut) 11264 ** is set to point to the new buffer containing the rebased changeset and 11265 ** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the 11266 ** responsibility of the caller to eventually free the new buffer using 11267 ** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut) 11268 ** are set to zero and an SQLite error code returned. 11269 */ 11270 SQLITE_API int sqlite3rebaser_rebase( 11271 sqlite3_rebaser*, 11272 int nIn, const void *pIn, 11273 int *pnOut, void **ppOut 11274 ); 11275 11276 /* 11277 ** CAPI3REF: Delete a changeset rebaser object. 11278 ** EXPERIMENTAL 11279 ** 11280 ** Delete the changeset rebaser object and all associated resources. There 11281 ** should be one call to this function for each successful invocation 11282 ** of sqlite3rebaser_create(). 11283 */ 11284 SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p); 11285 11286 /* 11287 ** CAPI3REF: Streaming Versions of API functions. 11288 ** 11289 ** The six streaming API xxx_strm() functions serve similar purposes to the 11290 ** corresponding non-streaming API functions: 11291 ** 11292 ** <table border=1 style="margin-left:8ex;margin-right:8ex"> 11293 ** <tr><th>Streaming function<th>Non-streaming equivalent</th> 11294 ** <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply] 11295 ** <tr><td>sqlite3changeset_apply_strm_v2<td>[sqlite3changeset_apply_v2] 11296 ** <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat] 11297 ** <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert] 11298 ** <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start] 11299 ** <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset] 11300 ** <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset] 11301 ** </table> 11302 ** 11303 ** Non-streaming functions that accept changesets (or patchsets) as input 11304 ** require that the entire changeset be stored in a single buffer in memory. 11305 ** Similarly, those that return a changeset or patchset do so by returning 11306 ** a pointer to a single large buffer allocated using sqlite3_malloc(). 11307 ** Normally this is convenient. However, if an application running in a 11308 ** low-memory environment is required to handle very large changesets, the 11309 ** large contiguous memory allocations required can become onerous. 11310 ** 11311 ** In order to avoid this problem, instead of a single large buffer, input 11312 ** is passed to a streaming API functions by way of a callback function that 11313 ** the sessions module invokes to incrementally request input data as it is 11314 ** required. In all cases, a pair of API function parameters such as 11315 ** 11316 ** <pre> 11317 ** int nChangeset, 11318 ** void *pChangeset, 11319 ** </pre> 11320 ** 11321 ** Is replaced by: 11322 ** 11323 ** <pre> 11324 ** int (*xInput)(void *pIn, void *pData, int *pnData), 11325 ** void *pIn, 11326 ** </pre> 11327 ** 11328 ** Each time the xInput callback is invoked by the sessions module, the first 11329 ** argument passed is a copy of the supplied pIn context pointer. The second 11330 ** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no 11331 ** error occurs the xInput method should copy up to (*pnData) bytes of data 11332 ** into the buffer and set (*pnData) to the actual number of bytes copied 11333 ** before returning SQLITE_OK. If the input is completely exhausted, (*pnData) 11334 ** should be set to zero to indicate this. Or, if an error occurs, an SQLite 11335 ** error code should be returned. In all cases, if an xInput callback returns 11336 ** an error, all processing is abandoned and the streaming API function 11337 ** returns a copy of the error code to the caller. 11338 ** 11339 ** In the case of sqlite3changeset_start_strm(), the xInput callback may be 11340 ** invoked by the sessions module at any point during the lifetime of the 11341 ** iterator. If such an xInput callback returns an error, the iterator enters 11342 ** an error state, whereby all subsequent calls to iterator functions 11343 ** immediately fail with the same error code as returned by xInput. 11344 ** 11345 ** Similarly, streaming API functions that return changesets (or patchsets) 11346 ** return them in chunks by way of a callback function instead of via a 11347 ** pointer to a single large buffer. In this case, a pair of parameters such 11348 ** as: 11349 ** 11350 ** <pre> 11351 ** int *pnChangeset, 11352 ** void **ppChangeset, 11353 ** </pre> 11354 ** 11355 ** Is replaced by: 11356 ** 11357 ** <pre> 11358 ** int (*xOutput)(void *pOut, const void *pData, int nData), 11359 ** void *pOut 11360 ** </pre> 11361 ** 11362 ** The xOutput callback is invoked zero or more times to return data to 11363 ** the application. The first parameter passed to each call is a copy of the 11364 ** pOut pointer supplied by the application. The second parameter, pData, 11365 ** points to a buffer nData bytes in size containing the chunk of output 11366 ** data being returned. If the xOutput callback successfully processes the 11367 ** supplied data, it should return SQLITE_OK to indicate success. Otherwise, 11368 ** it should return some other SQLite error code. In this case processing 11369 ** is immediately abandoned and the streaming API function returns a copy 11370 ** of the xOutput error code to the application. 11371 ** 11372 ** The sessions module never invokes an xOutput callback with the third 11373 ** parameter set to a value less than or equal to zero. Other than this, 11374 ** no guarantees are made as to the size of the chunks of data returned. 11375 */ 11376 SQLITE_API int sqlite3changeset_apply_strm( 11377 sqlite3 *db, /* Apply change to "main" db of this handle */ 11378 int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ 11379 void *pIn, /* First arg for xInput */ 11380 int(*xFilter)( 11381 void *pCtx, /* Copy of sixth arg to _apply() */ 11382 const char *zTab /* Table name */ 11383 ), 11384 int(*xConflict)( 11385 void *pCtx, /* Copy of sixth arg to _apply() */ 11386 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 11387 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 11388 ), 11389 void *pCtx /* First argument passed to xConflict */ 11390 ); 11391 SQLITE_API int sqlite3changeset_apply_v2_strm( 11392 sqlite3 *db, /* Apply change to "main" db of this handle */ 11393 int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ 11394 void *pIn, /* First arg for xInput */ 11395 int(*xFilter)( 11396 void *pCtx, /* Copy of sixth arg to _apply() */ 11397 const char *zTab /* Table name */ 11398 ), 11399 int(*xConflict)( 11400 void *pCtx, /* Copy of sixth arg to _apply() */ 11401 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 11402 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 11403 ), 11404 void *pCtx, /* First argument passed to xConflict */ 11405 void **ppRebase, int *pnRebase, 11406 int flags 11407 ); 11408 SQLITE_API int sqlite3changeset_concat_strm( 11409 int (*xInputA)(void *pIn, void *pData, int *pnData), 11410 void *pInA, 11411 int (*xInputB)(void *pIn, void *pData, int *pnData), 11412 void *pInB, 11413 int (*xOutput)(void *pOut, const void *pData, int nData), 11414 void *pOut 11415 ); 11416 SQLITE_API int sqlite3changeset_invert_strm( 11417 int (*xInput)(void *pIn, void *pData, int *pnData), 11418 void *pIn, 11419 int (*xOutput)(void *pOut, const void *pData, int nData), 11420 void *pOut 11421 ); 11422 SQLITE_API int sqlite3changeset_start_strm( 11423 sqlite3_changeset_iter **pp, 11424 int (*xInput)(void *pIn, void *pData, int *pnData), 11425 void *pIn 11426 ); 11427 SQLITE_API int sqlite3changeset_start_v2_strm( 11428 sqlite3_changeset_iter **pp, 11429 int (*xInput)(void *pIn, void *pData, int *pnData), 11430 void *pIn, 11431 int flags 11432 ); 11433 SQLITE_API int sqlite3session_changeset_strm( 11434 sqlite3_session *pSession, 11435 int (*xOutput)(void *pOut, const void *pData, int nData), 11436 void *pOut 11437 ); 11438 SQLITE_API int sqlite3session_patchset_strm( 11439 sqlite3_session *pSession, 11440 int (*xOutput)(void *pOut, const void *pData, int nData), 11441 void *pOut 11442 ); 11443 SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*, 11444 int (*xInput)(void *pIn, void *pData, int *pnData), 11445 void *pIn 11446 ); 11447 SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*, 11448 int (*xOutput)(void *pOut, const void *pData, int nData), 11449 void *pOut 11450 ); 11451 SQLITE_API int sqlite3rebaser_rebase_strm( 11452 sqlite3_rebaser *pRebaser, 11453 int (*xInput)(void *pIn, void *pData, int *pnData), 11454 void *pIn, 11455 int (*xOutput)(void *pOut, const void *pData, int nData), 11456 void *pOut 11457 ); 11458 11459 /* 11460 ** CAPI3REF: Configure global parameters 11461 ** 11462 ** The sqlite3session_config() interface is used to make global configuration 11463 ** changes to the sessions module in order to tune it to the specific needs 11464 ** of the application. 11465 ** 11466 ** The sqlite3session_config() interface is not threadsafe. If it is invoked 11467 ** while any other thread is inside any other sessions method then the 11468 ** results are undefined. Furthermore, if it is invoked after any sessions 11469 ** related objects have been created, the results are also undefined. 11470 ** 11471 ** The first argument to the sqlite3session_config() function must be one 11472 ** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The 11473 ** interpretation of the (void*) value passed as the second parameter and 11474 ** the effect of calling this function depends on the value of the first 11475 ** parameter. 11476 ** 11477 ** <dl> 11478 ** <dt>SQLITE_SESSION_CONFIG_STRMSIZE<dd> 11479 ** By default, the sessions module streaming interfaces attempt to input 11480 ** and output data in approximately 1 KiB chunks. This operand may be used 11481 ** to set and query the value of this configuration setting. The pointer 11482 ** passed as the second argument must point to a value of type (int). 11483 ** If this value is greater than 0, it is used as the new streaming data 11484 ** chunk size for both input and output. Before returning, the (int) value 11485 ** pointed to by pArg is set to the final value of the streaming interface 11486 ** chunk size. 11487 ** </dl> 11488 ** 11489 ** This function returns SQLITE_OK if successful, or an SQLite error code 11490 ** otherwise. 11491 */ 11492 SQLITE_API int sqlite3session_config(int op, void *pArg); 11493 11494 /* 11495 ** CAPI3REF: Values for sqlite3session_config(). 11496 */ 11497 #define SQLITE_SESSION_CONFIG_STRMSIZE 1 11498 11499 /* 11500 ** Make sure we can call this stuff from C++. 11501 */ 11502 #ifdef __cplusplus 11503 } 11504 #endif 11505 11506 #endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */ 11507 11508 /******** End of sqlite3session.h *********/ 11509 /******** Begin file fts5.h *********/ 11510 /* 11511 ** 2014 May 31 11512 ** 11513 ** The author disclaims copyright to this source code. In place of 11514 ** a legal notice, here is a blessing: 11515 ** 11516 ** May you do good and not evil. 11517 ** May you find forgiveness for yourself and forgive others. 11518 ** May you share freely, never taking more than you give. 11519 ** 11520 ****************************************************************************** 11521 ** 11522 ** Interfaces to extend FTS5. Using the interfaces defined in this file, 11523 ** FTS5 may be extended with: 11524 ** 11525 ** * custom tokenizers, and 11526 ** * custom auxiliary functions. 11527 */ 11528 11529 11530 #ifndef _FTS5_H 11531 #define _FTS5_H 11532 11533 11534 #ifdef __cplusplus 11535 extern "C" { 11536 #endif 11537 11538 /************************************************************************* 11539 ** CUSTOM AUXILIARY FUNCTIONS 11540 ** 11541 ** Virtual table implementations may overload SQL functions by implementing 11542 ** the sqlite3_module.xFindFunction() method. 11543 */ 11544 11545 typedef struct Fts5ExtensionApi Fts5ExtensionApi; 11546 typedef struct Fts5Context Fts5Context; 11547 typedef struct Fts5PhraseIter Fts5PhraseIter; 11548 11549 typedef void (*fts5_extension_function)( 11550 const Fts5ExtensionApi *pApi, /* API offered by current FTS version */ 11551 Fts5Context *pFts, /* First arg to pass to pApi functions */ 11552 sqlite3_context *pCtx, /* Context for returning result/error */ 11553 int nVal, /* Number of values in apVal[] array */ 11554 sqlite3_value **apVal /* Array of trailing arguments */ 11555 ); 11556 11557 struct Fts5PhraseIter { 11558 const unsigned char *a; 11559 const unsigned char *b; 11560 }; 11561 11562 /* 11563 ** EXTENSION API FUNCTIONS 11564 ** 11565 ** xUserData(pFts): 11566 ** Return a copy of the context pointer the extension function was 11567 ** registered with. 11568 ** 11569 ** xColumnTotalSize(pFts, iCol, pnToken): 11570 ** If parameter iCol is less than zero, set output variable *pnToken 11571 ** to the total number of tokens in the FTS5 table. Or, if iCol is 11572 ** non-negative but less than the number of columns in the table, return 11573 ** the total number of tokens in column iCol, considering all rows in 11574 ** the FTS5 table. 11575 ** 11576 ** If parameter iCol is greater than or equal to the number of columns 11577 ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. 11578 ** an OOM condition or IO error), an appropriate SQLite error code is 11579 ** returned. 11580 ** 11581 ** xColumnCount(pFts): 11582 ** Return the number of columns in the table. 11583 ** 11584 ** xColumnSize(pFts, iCol, pnToken): 11585 ** If parameter iCol is less than zero, set output variable *pnToken 11586 ** to the total number of tokens in the current row. Or, if iCol is 11587 ** non-negative but less than the number of columns in the table, set 11588 ** *pnToken to the number of tokens in column iCol of the current row. 11589 ** 11590 ** If parameter iCol is greater than or equal to the number of columns 11591 ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. 11592 ** an OOM condition or IO error), an appropriate SQLite error code is 11593 ** returned. 11594 ** 11595 ** This function may be quite inefficient if used with an FTS5 table 11596 ** created with the "columnsize=0" option. 11597 ** 11598 ** xColumnText: 11599 ** This function attempts to retrieve the text of column iCol of the 11600 ** current document. If successful, (*pz) is set to point to a buffer 11601 ** containing the text in utf-8 encoding, (*pn) is set to the size in bytes 11602 ** (not characters) of the buffer and SQLITE_OK is returned. Otherwise, 11603 ** if an error occurs, an SQLite error code is returned and the final values 11604 ** of (*pz) and (*pn) are undefined. 11605 ** 11606 ** xPhraseCount: 11607 ** Returns the number of phrases in the current query expression. 11608 ** 11609 ** xPhraseSize: 11610 ** Returns the number of tokens in phrase iPhrase of the query. Phrases 11611 ** are numbered starting from zero. 11612 ** 11613 ** xInstCount: 11614 ** Set *pnInst to the total number of occurrences of all phrases within 11615 ** the query within the current row. Return SQLITE_OK if successful, or 11616 ** an error code (i.e. SQLITE_NOMEM) if an error occurs. 11617 ** 11618 ** This API can be quite slow if used with an FTS5 table created with the 11619 ** "detail=none" or "detail=column" option. If the FTS5 table is created 11620 ** with either "detail=none" or "detail=column" and "content=" option 11621 ** (i.e. if it is a contentless table), then this API always returns 0. 11622 ** 11623 ** xInst: 11624 ** Query for the details of phrase match iIdx within the current row. 11625 ** Phrase matches are numbered starting from zero, so the iIdx argument 11626 ** should be greater than or equal to zero and smaller than the value 11627 ** output by xInstCount(). 11628 ** 11629 ** Usually, output parameter *piPhrase is set to the phrase number, *piCol 11630 ** to the column in which it occurs and *piOff the token offset of the 11631 ** first token of the phrase. Returns SQLITE_OK if successful, or an error 11632 ** code (i.e. SQLITE_NOMEM) if an error occurs. 11633 ** 11634 ** This API can be quite slow if used with an FTS5 table created with the 11635 ** "detail=none" or "detail=column" option. 11636 ** 11637 ** xRowid: 11638 ** Returns the rowid of the current row. 11639 ** 11640 ** xTokenize: 11641 ** Tokenize text using the tokenizer belonging to the FTS5 table. 11642 ** 11643 ** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback): 11644 ** This API function is used to query the FTS table for phrase iPhrase 11645 ** of the current query. Specifically, a query equivalent to: 11646 ** 11647 ** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid 11648 ** 11649 ** with $p set to a phrase equivalent to the phrase iPhrase of the 11650 ** current query is executed. Any column filter that applies to 11651 ** phrase iPhrase of the current query is included in $p. For each 11652 ** row visited, the callback function passed as the fourth argument 11653 ** is invoked. The context and API objects passed to the callback 11654 ** function may be used to access the properties of each matched row. 11655 ** Invoking Api.xUserData() returns a copy of the pointer passed as 11656 ** the third argument to pUserData. 11657 ** 11658 ** If the callback function returns any value other than SQLITE_OK, the 11659 ** query is abandoned and the xQueryPhrase function returns immediately. 11660 ** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK. 11661 ** Otherwise, the error code is propagated upwards. 11662 ** 11663 ** If the query runs to completion without incident, SQLITE_OK is returned. 11664 ** Or, if some error occurs before the query completes or is aborted by 11665 ** the callback, an SQLite error code is returned. 11666 ** 11667 ** 11668 ** xSetAuxdata(pFts5, pAux, xDelete) 11669 ** 11670 ** Save the pointer passed as the second argument as the extension function's 11671 ** "auxiliary data". The pointer may then be retrieved by the current or any 11672 ** future invocation of the same fts5 extension function made as part of 11673 ** the same MATCH query using the xGetAuxdata() API. 11674 ** 11675 ** Each extension function is allocated a single auxiliary data slot for 11676 ** each FTS query (MATCH expression). If the extension function is invoked 11677 ** more than once for a single FTS query, then all invocations share a 11678 ** single auxiliary data context. 11679 ** 11680 ** If there is already an auxiliary data pointer when this function is 11681 ** invoked, then it is replaced by the new pointer. If an xDelete callback 11682 ** was specified along with the original pointer, it is invoked at this 11683 ** point. 11684 ** 11685 ** The xDelete callback, if one is specified, is also invoked on the 11686 ** auxiliary data pointer after the FTS5 query has finished. 11687 ** 11688 ** If an error (e.g. an OOM condition) occurs within this function, 11689 ** the auxiliary data is set to NULL and an error code returned. If the 11690 ** xDelete parameter was not NULL, it is invoked on the auxiliary data 11691 ** pointer before returning. 11692 ** 11693 ** 11694 ** xGetAuxdata(pFts5, bClear) 11695 ** 11696 ** Returns the current auxiliary data pointer for the fts5 extension 11697 ** function. See the xSetAuxdata() method for details. 11698 ** 11699 ** If the bClear argument is non-zero, then the auxiliary data is cleared 11700 ** (set to NULL) before this function returns. In this case the xDelete, 11701 ** if any, is not invoked. 11702 ** 11703 ** 11704 ** xRowCount(pFts5, pnRow) 11705 ** 11706 ** This function is used to retrieve the total number of rows in the table. 11707 ** In other words, the same value that would be returned by: 11708 ** 11709 ** SELECT count(*) FROM ftstable; 11710 ** 11711 ** xPhraseFirst() 11712 ** This function is used, along with type Fts5PhraseIter and the xPhraseNext 11713 ** method, to iterate through all instances of a single query phrase within 11714 ** the current row. This is the same information as is accessible via the 11715 ** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient 11716 ** to use, this API may be faster under some circumstances. To iterate 11717 ** through instances of phrase iPhrase, use the following code: 11718 ** 11719 ** Fts5PhraseIter iter; 11720 ** int iCol, iOff; 11721 ** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff); 11722 ** iCol>=0; 11723 ** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff) 11724 ** ){ 11725 ** // An instance of phrase iPhrase at offset iOff of column iCol 11726 ** } 11727 ** 11728 ** The Fts5PhraseIter structure is defined above. Applications should not 11729 ** modify this structure directly - it should only be used as shown above 11730 ** with the xPhraseFirst() and xPhraseNext() API methods (and by 11731 ** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below). 11732 ** 11733 ** This API can be quite slow if used with an FTS5 table created with the 11734 ** "detail=none" or "detail=column" option. If the FTS5 table is created 11735 ** with either "detail=none" or "detail=column" and "content=" option 11736 ** (i.e. if it is a contentless table), then this API always iterates 11737 ** through an empty set (all calls to xPhraseFirst() set iCol to -1). 11738 ** 11739 ** xPhraseNext() 11740 ** See xPhraseFirst above. 11741 ** 11742 ** xPhraseFirstColumn() 11743 ** This function and xPhraseNextColumn() are similar to the xPhraseFirst() 11744 ** and xPhraseNext() APIs described above. The difference is that instead 11745 ** of iterating through all instances of a phrase in the current row, these 11746 ** APIs are used to iterate through the set of columns in the current row 11747 ** that contain one or more instances of a specified phrase. For example: 11748 ** 11749 ** Fts5PhraseIter iter; 11750 ** int iCol; 11751 ** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol); 11752 ** iCol>=0; 11753 ** pApi->xPhraseNextColumn(pFts, &iter, &iCol) 11754 ** ){ 11755 ** // Column iCol contains at least one instance of phrase iPhrase 11756 ** } 11757 ** 11758 ** This API can be quite slow if used with an FTS5 table created with the 11759 ** "detail=none" option. If the FTS5 table is created with either 11760 ** "detail=none" "content=" option (i.e. if it is a contentless table), 11761 ** then this API always iterates through an empty set (all calls to 11762 ** xPhraseFirstColumn() set iCol to -1). 11763 ** 11764 ** The information accessed using this API and its companion 11765 ** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext 11766 ** (or xInst/xInstCount). The chief advantage of this API is that it is 11767 ** significantly more efficient than those alternatives when used with 11768 ** "detail=column" tables. 11769 ** 11770 ** xPhraseNextColumn() 11771 ** See xPhraseFirstColumn above. 11772 */ 11773 struct Fts5ExtensionApi { 11774 int iVersion; /* Currently always set to 3 */ 11775 11776 void *(*xUserData)(Fts5Context*); 11777 11778 int (*xColumnCount)(Fts5Context*); 11779 int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow); 11780 int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken); 11781 11782 int (*xTokenize)(Fts5Context*, 11783 const char *pText, int nText, /* Text to tokenize */ 11784 void *pCtx, /* Context passed to xToken() */ 11785 int (*xToken)(void*, int, const char*, int, int, int) /* Callback */ 11786 ); 11787 11788 int (*xPhraseCount)(Fts5Context*); 11789 int (*xPhraseSize)(Fts5Context*, int iPhrase); 11790 11791 int (*xInstCount)(Fts5Context*, int *pnInst); 11792 int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff); 11793 11794 sqlite3_int64 (*xRowid)(Fts5Context*); 11795 int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn); 11796 int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken); 11797 11798 int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData, 11799 int(*)(const Fts5ExtensionApi*,Fts5Context*,void*) 11800 ); 11801 int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*)); 11802 void *(*xGetAuxdata)(Fts5Context*, int bClear); 11803 11804 int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*); 11805 void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff); 11806 11807 int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*); 11808 void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol); 11809 }; 11810 11811 /* 11812 ** CUSTOM AUXILIARY FUNCTIONS 11813 *************************************************************************/ 11814 11815 /************************************************************************* 11816 ** CUSTOM TOKENIZERS 11817 ** 11818 ** Applications may also register custom tokenizer types. A tokenizer 11819 ** is registered by providing fts5 with a populated instance of the 11820 ** following structure. All structure methods must be defined, setting 11821 ** any member of the fts5_tokenizer struct to NULL leads to undefined 11822 ** behaviour. The structure methods are expected to function as follows: 11823 ** 11824 ** xCreate: 11825 ** This function is used to allocate and initialize a tokenizer instance. 11826 ** A tokenizer instance is required to actually tokenize text. 11827 ** 11828 ** The first argument passed to this function is a copy of the (void*) 11829 ** pointer provided by the application when the fts5_tokenizer object 11830 ** was registered with FTS5 (the third argument to xCreateTokenizer()). 11831 ** The second and third arguments are an array of nul-terminated strings 11832 ** containing the tokenizer arguments, if any, specified following the 11833 ** tokenizer name as part of the CREATE VIRTUAL TABLE statement used 11834 ** to create the FTS5 table. 11835 ** 11836 ** The final argument is an output variable. If successful, (*ppOut) 11837 ** should be set to point to the new tokenizer handle and SQLITE_OK 11838 ** returned. If an error occurs, some value other than SQLITE_OK should 11839 ** be returned. In this case, fts5 assumes that the final value of *ppOut 11840 ** is undefined. 11841 ** 11842 ** xDelete: 11843 ** This function is invoked to delete a tokenizer handle previously 11844 ** allocated using xCreate(). Fts5 guarantees that this function will 11845 ** be invoked exactly once for each successful call to xCreate(). 11846 ** 11847 ** xTokenize: 11848 ** This function is expected to tokenize the nText byte string indicated 11849 ** by argument pText. pText may or may not be nul-terminated. The first 11850 ** argument passed to this function is a pointer to an Fts5Tokenizer object 11851 ** returned by an earlier call to xCreate(). 11852 ** 11853 ** The second argument indicates the reason that FTS5 is requesting 11854 ** tokenization of the supplied text. This is always one of the following 11855 ** four values: 11856 ** 11857 ** <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into 11858 ** or removed from the FTS table. The tokenizer is being invoked to 11859 ** determine the set of tokens to add to (or delete from) the 11860 ** FTS index. 11861 ** 11862 ** <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed 11863 ** against the FTS index. The tokenizer is being called to tokenize 11864 ** a bareword or quoted string specified as part of the query. 11865 ** 11866 ** <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as 11867 ** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is 11868 ** followed by a "*" character, indicating that the last token 11869 ** returned by the tokenizer will be treated as a token prefix. 11870 ** 11871 ** <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to 11872 ** satisfy an fts5_api.xTokenize() request made by an auxiliary 11873 ** function. Or an fts5_api.xColumnSize() request made by the same 11874 ** on a columnsize=0 database. 11875 ** </ul> 11876 ** 11877 ** For each token in the input string, the supplied callback xToken() must 11878 ** be invoked. The first argument to it should be a copy of the pointer 11879 ** passed as the second argument to xTokenize(). The third and fourth 11880 ** arguments are a pointer to a buffer containing the token text, and the 11881 ** size of the token in bytes. The 4th and 5th arguments are the byte offsets 11882 ** of the first byte of and first byte immediately following the text from 11883 ** which the token is derived within the input. 11884 ** 11885 ** The second argument passed to the xToken() callback ("tflags") should 11886 ** normally be set to 0. The exception is if the tokenizer supports 11887 ** synonyms. In this case see the discussion below for details. 11888 ** 11889 ** FTS5 assumes the xToken() callback is invoked for each token in the 11890 ** order that they occur within the input text. 11891 ** 11892 ** If an xToken() callback returns any value other than SQLITE_OK, then 11893 ** the tokenization should be abandoned and the xTokenize() method should 11894 ** immediately return a copy of the xToken() return value. Or, if the 11895 ** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally, 11896 ** if an error occurs with the xTokenize() implementation itself, it 11897 ** may abandon the tokenization and return any error code other than 11898 ** SQLITE_OK or SQLITE_DONE. 11899 ** 11900 ** SYNONYM SUPPORT 11901 ** 11902 ** Custom tokenizers may also support synonyms. Consider a case in which a 11903 ** user wishes to query for a phrase such as "first place". Using the 11904 ** built-in tokenizers, the FTS5 query 'first + place' will match instances 11905 ** of "first place" within the document set, but not alternative forms 11906 ** such as "1st place". In some applications, it would be better to match 11907 ** all instances of "first place" or "1st place" regardless of which form 11908 ** the user specified in the MATCH query text. 11909 ** 11910 ** There are several ways to approach this in FTS5: 11911 ** 11912 ** <ol><li> By mapping all synonyms to a single token. In this case, using 11913 ** the above example, this means that the tokenizer returns the 11914 ** same token for inputs "first" and "1st". Say that token is in 11915 ** fact "first", so that when the user inserts the document "I won 11916 ** 1st place" entries are added to the index for tokens "i", "won", 11917 ** "first" and "place". If the user then queries for '1st + place', 11918 ** the tokenizer substitutes "first" for "1st" and the query works 11919 ** as expected. 11920 ** 11921 ** <li> By querying the index for all synonyms of each query term 11922 ** separately. In this case, when tokenizing query text, the 11923 ** tokenizer may provide multiple synonyms for a single term 11924 ** within the document. FTS5 then queries the index for each 11925 ** synonym individually. For example, faced with the query: 11926 ** 11927 ** <codeblock> 11928 ** ... MATCH 'first place'</codeblock> 11929 ** 11930 ** the tokenizer offers both "1st" and "first" as synonyms for the 11931 ** first token in the MATCH query and FTS5 effectively runs a query 11932 ** similar to: 11933 ** 11934 ** <codeblock> 11935 ** ... MATCH '(first OR 1st) place'</codeblock> 11936 ** 11937 ** except that, for the purposes of auxiliary functions, the query 11938 ** still appears to contain just two phrases - "(first OR 1st)" 11939 ** being treated as a single phrase. 11940 ** 11941 ** <li> By adding multiple synonyms for a single term to the FTS index. 11942 ** Using this method, when tokenizing document text, the tokenizer 11943 ** provides multiple synonyms for each token. So that when a 11944 ** document such as "I won first place" is tokenized, entries are 11945 ** added to the FTS index for "i", "won", "first", "1st" and 11946 ** "place". 11947 ** 11948 ** This way, even if the tokenizer does not provide synonyms 11949 ** when tokenizing query text (it should not - to do so would be 11950 ** inefficient), it doesn't matter if the user queries for 11951 ** 'first + place' or '1st + place', as there are entries in the 11952 ** FTS index corresponding to both forms of the first token. 11953 ** </ol> 11954 ** 11955 ** Whether it is parsing document or query text, any call to xToken that 11956 ** specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit 11957 ** is considered to supply a synonym for the previous token. For example, 11958 ** when parsing the document "I won first place", a tokenizer that supports 11959 ** synonyms would call xToken() 5 times, as follows: 11960 ** 11961 ** <codeblock> 11962 ** xToken(pCtx, 0, "i", 1, 0, 1); 11963 ** xToken(pCtx, 0, "won", 3, 2, 5); 11964 ** xToken(pCtx, 0, "first", 5, 6, 11); 11965 ** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11); 11966 ** xToken(pCtx, 0, "place", 5, 12, 17); 11967 **</codeblock> 11968 ** 11969 ** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time 11970 ** xToken() is called. Multiple synonyms may be specified for a single token 11971 ** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence. 11972 ** There is no limit to the number of synonyms that may be provided for a 11973 ** single token. 11974 ** 11975 ** In many cases, method (1) above is the best approach. It does not add 11976 ** extra data to the FTS index or require FTS5 to query for multiple terms, 11977 ** so it is efficient in terms of disk space and query speed. However, it 11978 ** does not support prefix queries very well. If, as suggested above, the 11979 ** token "first" is substituted for "1st" by the tokenizer, then the query: 11980 ** 11981 ** <codeblock> 11982 ** ... MATCH '1s*'</codeblock> 11983 ** 11984 ** will not match documents that contain the token "1st" (as the tokenizer 11985 ** will probably not map "1s" to any prefix of "first"). 11986 ** 11987 ** For full prefix support, method (3) may be preferred. In this case, 11988 ** because the index contains entries for both "first" and "1st", prefix 11989 ** queries such as 'fi*' or '1s*' will match correctly. However, because 11990 ** extra entries are added to the FTS index, this method uses more space 11991 ** within the database. 11992 ** 11993 ** Method (2) offers a midpoint between (1) and (3). Using this method, 11994 ** a query such as '1s*' will match documents that contain the literal 11995 ** token "1st", but not "first" (assuming the tokenizer is not able to 11996 ** provide synonyms for prefixes). However, a non-prefix query like '1st' 11997 ** will match against "1st" and "first". This method does not require 11998 ** extra disk space, as no extra entries are added to the FTS index. 11999 ** On the other hand, it may require more CPU cycles to run MATCH queries, 12000 ** as separate queries of the FTS index are required for each synonym. 12001 ** 12002 ** When using methods (2) or (3), it is important that the tokenizer only 12003 ** provide synonyms when tokenizing document text (method (2)) or query 12004 ** text (method (3)), not both. Doing so will not cause any errors, but is 12005 ** inefficient. 12006 */ 12007 typedef struct Fts5Tokenizer Fts5Tokenizer; 12008 typedef struct fts5_tokenizer fts5_tokenizer; 12009 struct fts5_tokenizer { 12010 int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut); 12011 void (*xDelete)(Fts5Tokenizer*); 12012 int (*xTokenize)(Fts5Tokenizer*, 12013 void *pCtx, 12014 int flags, /* Mask of FTS5_TOKENIZE_* flags */ 12015 const char *pText, int nText, 12016 int (*xToken)( 12017 void *pCtx, /* Copy of 2nd argument to xTokenize() */ 12018 int tflags, /* Mask of FTS5_TOKEN_* flags */ 12019 const char *pToken, /* Pointer to buffer containing token */ 12020 int nToken, /* Size of token in bytes */ 12021 int iStart, /* Byte offset of token within input text */ 12022 int iEnd /* Byte offset of end of token within input text */ 12023 ) 12024 ); 12025 }; 12026 12027 /* Flags that may be passed as the third argument to xTokenize() */ 12028 #define FTS5_TOKENIZE_QUERY 0x0001 12029 #define FTS5_TOKENIZE_PREFIX 0x0002 12030 #define FTS5_TOKENIZE_DOCUMENT 0x0004 12031 #define FTS5_TOKENIZE_AUX 0x0008 12032 12033 /* Flags that may be passed by the tokenizer implementation back to FTS5 12034 ** as the third argument to the supplied xToken callback. */ 12035 #define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */ 12036 12037 /* 12038 ** END OF CUSTOM TOKENIZERS 12039 *************************************************************************/ 12040 12041 /************************************************************************* 12042 ** FTS5 EXTENSION REGISTRATION API 12043 */ 12044 typedef struct fts5_api fts5_api; 12045 struct fts5_api { 12046 int iVersion; /* Currently always set to 2 */ 12047 12048 /* Create a new tokenizer */ 12049 int (*xCreateTokenizer)( 12050 fts5_api *pApi, 12051 const char *zName, 12052 void *pContext, 12053 fts5_tokenizer *pTokenizer, 12054 void (*xDestroy)(void*) 12055 ); 12056 12057 /* Find an existing tokenizer */ 12058 int (*xFindTokenizer)( 12059 fts5_api *pApi, 12060 const char *zName, 12061 void **ppContext, 12062 fts5_tokenizer *pTokenizer 12063 ); 12064 12065 /* Create a new auxiliary function */ 12066 int (*xCreateFunction)( 12067 fts5_api *pApi, 12068 const char *zName, 12069 void *pContext, 12070 fts5_extension_function xFunction, 12071 void (*xDestroy)(void*) 12072 ); 12073 }; 12074 12075 /* 12076 ** END OF REGISTRATION API 12077 *************************************************************************/ 12078 12079 #ifdef __cplusplus 12080 } /* end of the 'extern "C"' block */ 12081 #endif 12082 12083 #endif /* _FTS5_H */ 12084 12085 /******** End of fts5.h *********/ 12086 #else // USE_LIBSQLITE3 12087 // If users really want to link against the system sqlite3 we 12088 // need to make this file a noop. 12089 #endif 12090 /* 12091 ** 2014-09-08 12092 ** 12093 ** The author disclaims copyright to this source code. In place of 12094 ** a legal notice, here is a blessing: 12095 ** 12096 ** May you do good and not evil. 12097 ** May you find forgiveness for yourself and forgive others. 12098 ** May you share freely, never taking more than you give. 12099 ** 12100 ************************************************************************* 12101 ** 12102 ** This file contains the application interface definitions for the 12103 ** user-authentication extension feature. 12104 ** 12105 ** To compile with the user-authentication feature, append this file to 12106 ** end of an SQLite amalgamation header file ("sqlite3.h"), then add 12107 ** the SQLITE_USER_AUTHENTICATION compile-time option. See the 12108 ** user-auth.txt file in the same source directory as this file for 12109 ** additional information. 12110 */ 12111 #ifdef SQLITE_USER_AUTHENTICATION 12112 12113 #ifdef __cplusplus 12114 extern "C" { 12115 #endif 12116 12117 /* 12118 ** If a database contains the SQLITE_USER table, then the 12119 ** sqlite3_user_authenticate() interface must be invoked with an 12120 ** appropriate username and password prior to enable read and write 12121 ** access to the database. 12122 ** 12123 ** Return SQLITE_OK on success or SQLITE_ERROR if the username/password 12124 ** combination is incorrect or unknown. 12125 ** 12126 ** If the SQLITE_USER table is not present in the database file, then 12127 ** this interface is a harmless no-op returnning SQLITE_OK. 12128 */ 12129 int sqlite3_user_authenticate( 12130 sqlite3 *db, /* The database connection */ 12131 const char *zUsername, /* Username */ 12132 const char *aPW, /* Password or credentials */ 12133 int nPW /* Number of bytes in aPW[] */ 12134 ); 12135 12136 /* 12137 ** The sqlite3_user_add() interface can be used (by an admin user only) 12138 ** to create a new user. When called on a no-authentication-required 12139 ** database, this routine converts the database into an authentication- 12140 ** required database, automatically makes the added user an 12141 ** administrator, and logs in the current connection as that user. 12142 ** The sqlite3_user_add() interface only works for the "main" database, not 12143 ** for any ATTACH-ed databases. Any call to sqlite3_user_add() by a 12144 ** non-admin user results in an error. 12145 */ 12146 int sqlite3_user_add( 12147 sqlite3 *db, /* Database connection */ 12148 const char *zUsername, /* Username to be added */ 12149 const char *aPW, /* Password or credentials */ 12150 int nPW, /* Number of bytes in aPW[] */ 12151 int isAdmin /* True to give new user admin privilege */ 12152 ); 12153 12154 /* 12155 ** The sqlite3_user_change() interface can be used to change a users 12156 ** login credentials or admin privilege. Any user can change their own 12157 ** login credentials. Only an admin user can change another users login 12158 ** credentials or admin privilege setting. No user may change their own 12159 ** admin privilege setting. 12160 */ 12161 int sqlite3_user_change( 12162 sqlite3 *db, /* Database connection */ 12163 const char *zUsername, /* Username to change */ 12164 const char *aPW, /* New password or credentials */ 12165 int nPW, /* Number of bytes in aPW[] */ 12166 int isAdmin /* Modified admin privilege for the user */ 12167 ); 12168 12169 /* 12170 ** The sqlite3_user_delete() interface can be used (by an admin user only) 12171 ** to delete a user. The currently logged-in user cannot be deleted, 12172 ** which guarantees that there is always an admin user and hence that 12173 ** the database cannot be converted into a no-authentication-required 12174 ** database. 12175 */ 12176 int sqlite3_user_delete( 12177 sqlite3 *db, /* Database connection */ 12178 const char *zUsername /* Username to remove */ 12179 ); 12180 12181 #ifdef __cplusplus 12182 } /* end of the 'extern "C"' block */ 12183 #endif 12184 12185 #endif /* SQLITE_USER_AUTHENTICATION */ 12186