1 /*
2 ** 2003 September 6
3 **
4 ** The author disclaims copyright to this source code. In place of
5 ** a legal notice, here is a blessing:
6 **
7 ** May you do good and not evil.
8 ** May you find forgiveness for yourself and forgive others.
9 ** May you share freely, never taking more than you give.
10 **
11 *************************************************************************
12 ** This file contains code used for creating, destroying, and populating
13 ** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.)
14 */
15 #include "sqliteInt.h"
16 #include "vdbeInt.h"
17
18 /* Forward references */
19 static void freeEphemeralFunction(sqlite3 *db, FuncDef *pDef);
20 static void vdbeFreeOpArray(sqlite3 *, Op *, int);
21
22 /*
23 ** Create a new virtual database engine.
24 */
sqlite3VdbeCreate(Parse * pParse)25 Vdbe *sqlite3VdbeCreate(Parse *pParse){
26 sqlite3 *db = pParse->db;
27 Vdbe *p;
28 p = sqlite3DbMallocRawNN(db, sizeof(Vdbe) );
29 if( p==0 ) return 0;
30 memset(&p->aOp, 0, sizeof(Vdbe)-offsetof(Vdbe,aOp));
31 p->db = db;
32 if( db->pVdbe ){
33 db->pVdbe->pPrev = p;
34 }
35 p->pNext = db->pVdbe;
36 p->pPrev = 0;
37 db->pVdbe = p;
38 p->iVdbeMagic = VDBE_MAGIC_INIT;
39 p->pParse = pParse;
40 pParse->pVdbe = p;
41 assert( pParse->aLabel==0 );
42 assert( pParse->nLabel==0 );
43 assert( p->nOpAlloc==0 );
44 assert( pParse->szOpAlloc==0 );
45 sqlite3VdbeAddOp2(p, OP_Init, 0, 1);
46 return p;
47 }
48
49 /*
50 ** Return the Parse object that owns a Vdbe object.
51 */
sqlite3VdbeParser(Vdbe * p)52 Parse *sqlite3VdbeParser(Vdbe *p){
53 return p->pParse;
54 }
55
56 /*
57 ** Change the error string stored in Vdbe.zErrMsg
58 */
sqlite3VdbeError(Vdbe * p,const char * zFormat,...)59 void sqlite3VdbeError(Vdbe *p, const char *zFormat, ...){
60 va_list ap;
61 sqlite3DbFree(p->db, p->zErrMsg);
62 va_start(ap, zFormat);
63 p->zErrMsg = sqlite3VMPrintf(p->db, zFormat, ap);
64 va_end(ap);
65 }
66
67 /*
68 ** Remember the SQL string for a prepared statement.
69 */
sqlite3VdbeSetSql(Vdbe * p,const char * z,int n,u8 prepFlags)70 void sqlite3VdbeSetSql(Vdbe *p, const char *z, int n, u8 prepFlags){
71 if( p==0 ) return;
72 p->prepFlags = prepFlags;
73 if( (prepFlags & SQLITE_PREPARE_SAVESQL)==0 ){
74 p->expmask = 0;
75 }
76 assert( p->zSql==0 );
77 p->zSql = sqlite3DbStrNDup(p->db, z, n);
78 }
79
80 #ifdef SQLITE_ENABLE_NORMALIZE
81 /*
82 ** Add a new element to the Vdbe->pDblStr list.
83 */
sqlite3VdbeAddDblquoteStr(sqlite3 * db,Vdbe * p,const char * z)84 void sqlite3VdbeAddDblquoteStr(sqlite3 *db, Vdbe *p, const char *z){
85 if( p ){
86 int n = sqlite3Strlen30(z);
87 DblquoteStr *pStr = sqlite3DbMallocRawNN(db,
88 sizeof(*pStr)+n+1-sizeof(pStr->z));
89 if( pStr ){
90 pStr->pNextStr = p->pDblStr;
91 p->pDblStr = pStr;
92 memcpy(pStr->z, z, n+1);
93 }
94 }
95 }
96 #endif
97
98 #ifdef SQLITE_ENABLE_NORMALIZE
99 /*
100 ** zId of length nId is a double-quoted identifier. Check to see if
101 ** that identifier is really used as a string literal.
102 */
sqlite3VdbeUsesDoubleQuotedString(Vdbe * pVdbe,const char * zId)103 int sqlite3VdbeUsesDoubleQuotedString(
104 Vdbe *pVdbe, /* The prepared statement */
105 const char *zId /* The double-quoted identifier, already dequoted */
106 ){
107 DblquoteStr *pStr;
108 assert( zId!=0 );
109 if( pVdbe->pDblStr==0 ) return 0;
110 for(pStr=pVdbe->pDblStr; pStr; pStr=pStr->pNextStr){
111 if( strcmp(zId, pStr->z)==0 ) return 1;
112 }
113 return 0;
114 }
115 #endif
116
117 /*
118 ** Swap all content between two VDBE structures.
119 */
sqlite3VdbeSwap(Vdbe * pA,Vdbe * pB)120 void sqlite3VdbeSwap(Vdbe *pA, Vdbe *pB){
121 Vdbe tmp, *pTmp;
122 char *zTmp;
123 assert( pA->db==pB->db );
124 tmp = *pA;
125 *pA = *pB;
126 *pB = tmp;
127 pTmp = pA->pNext;
128 pA->pNext = pB->pNext;
129 pB->pNext = pTmp;
130 pTmp = pA->pPrev;
131 pA->pPrev = pB->pPrev;
132 pB->pPrev = pTmp;
133 zTmp = pA->zSql;
134 pA->zSql = pB->zSql;
135 pB->zSql = zTmp;
136 #ifdef SQLITE_ENABLE_NORMALIZE
137 zTmp = pA->zNormSql;
138 pA->zNormSql = pB->zNormSql;
139 pB->zNormSql = zTmp;
140 #endif
141 pB->expmask = pA->expmask;
142 pB->prepFlags = pA->prepFlags;
143 memcpy(pB->aCounter, pA->aCounter, sizeof(pB->aCounter));
144 pB->aCounter[SQLITE_STMTSTATUS_REPREPARE]++;
145 }
146
147 /*
148 ** Resize the Vdbe.aOp array so that it is at least nOp elements larger
149 ** than its current size. nOp is guaranteed to be less than or equal
150 ** to 1024/sizeof(Op).
151 **
152 ** If an out-of-memory error occurs while resizing the array, return
153 ** SQLITE_NOMEM. In this case Vdbe.aOp and Vdbe.nOpAlloc remain
154 ** unchanged (this is so that any opcodes already allocated can be
155 ** correctly deallocated along with the rest of the Vdbe).
156 */
growOpArray(Vdbe * v,int nOp)157 static int growOpArray(Vdbe *v, int nOp){
158 VdbeOp *pNew;
159 Parse *p = v->pParse;
160
161 /* The SQLITE_TEST_REALLOC_STRESS compile-time option is designed to force
162 ** more frequent reallocs and hence provide more opportunities for
163 ** simulated OOM faults. SQLITE_TEST_REALLOC_STRESS is generally used
164 ** during testing only. With SQLITE_TEST_REALLOC_STRESS grow the op array
165 ** by the minimum* amount required until the size reaches 512. Normal
166 ** operation (without SQLITE_TEST_REALLOC_STRESS) is to double the current
167 ** size of the op array or add 1KB of space, whichever is smaller. */
168 #ifdef SQLITE_TEST_REALLOC_STRESS
169 sqlite3_int64 nNew = (v->nOpAlloc>=512 ? 2*(sqlite3_int64)v->nOpAlloc
170 : (sqlite3_int64)v->nOpAlloc+nOp);
171 #else
172 sqlite3_int64 nNew = (v->nOpAlloc ? 2*(sqlite3_int64)v->nOpAlloc
173 : (sqlite3_int64)(1024/sizeof(Op)));
174 UNUSED_PARAMETER(nOp);
175 #endif
176
177 /* Ensure that the size of a VDBE does not grow too large */
178 if( nNew > p->db->aLimit[SQLITE_LIMIT_VDBE_OP] ){
179 sqlite3OomFault(p->db);
180 return SQLITE_NOMEM;
181 }
182
183 assert( nOp<=(1024/sizeof(Op)) );
184 assert( nNew>=(v->nOpAlloc+nOp) );
185 pNew = sqlite3DbRealloc(p->db, v->aOp, nNew*sizeof(Op));
186 if( pNew ){
187 p->szOpAlloc = sqlite3DbMallocSize(p->db, pNew);
188 v->nOpAlloc = p->szOpAlloc/sizeof(Op);
189 v->aOp = pNew;
190 }
191 return (pNew ? SQLITE_OK : SQLITE_NOMEM_BKPT);
192 }
193
194 #ifdef SQLITE_DEBUG
195 /* This routine is just a convenient place to set a breakpoint that will
196 ** fire after each opcode is inserted and displayed using
197 ** "PRAGMA vdbe_addoptrace=on". Parameters "pc" (program counter) and
198 ** pOp are available to make the breakpoint conditional.
199 **
200 ** Other useful labels for breakpoints include:
201 ** test_trace_breakpoint(pc,pOp)
202 ** sqlite3CorruptError(lineno)
203 ** sqlite3MisuseError(lineno)
204 ** sqlite3CantopenError(lineno)
205 */
test_addop_breakpoint(int pc,Op * pOp)206 static void test_addop_breakpoint(int pc, Op *pOp){
207 static int n = 0;
208 n++;
209 }
210 #endif
211
212 /*
213 ** Add a new instruction to the list of instructions current in the
214 ** VDBE. Return the address of the new instruction.
215 **
216 ** Parameters:
217 **
218 ** p Pointer to the VDBE
219 **
220 ** op The opcode for this instruction
221 **
222 ** p1, p2, p3 Operands
223 **
224 ** Use the sqlite3VdbeResolveLabel() function to fix an address and
225 ** the sqlite3VdbeChangeP4() function to change the value of the P4
226 ** operand.
227 */
growOp3(Vdbe * p,int op,int p1,int p2,int p3)228 static SQLITE_NOINLINE int growOp3(Vdbe *p, int op, int p1, int p2, int p3){
229 assert( p->nOpAlloc<=p->nOp );
230 if( growOpArray(p, 1) ) return 1;
231 assert( p->nOpAlloc>p->nOp );
232 return sqlite3VdbeAddOp3(p, op, p1, p2, p3);
233 }
sqlite3VdbeAddOp3(Vdbe * p,int op,int p1,int p2,int p3)234 int sqlite3VdbeAddOp3(Vdbe *p, int op, int p1, int p2, int p3){
235 int i;
236 VdbeOp *pOp;
237
238 i = p->nOp;
239 assert( p->iVdbeMagic==VDBE_MAGIC_INIT );
240 assert( op>=0 && op<0xff );
241 if( p->nOpAlloc<=i ){
242 return growOp3(p, op, p1, p2, p3);
243 }
244 p->nOp++;
245 pOp = &p->aOp[i];
246 pOp->opcode = (u8)op;
247 pOp->p5 = 0;
248 pOp->p1 = p1;
249 pOp->p2 = p2;
250 pOp->p3 = p3;
251 pOp->p4.p = 0;
252 pOp->p4type = P4_NOTUSED;
253 #ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
254 pOp->zComment = 0;
255 #endif
256 #ifdef SQLITE_DEBUG
257 if( p->db->flags & SQLITE_VdbeAddopTrace ){
258 sqlite3VdbePrintOp(0, i, &p->aOp[i]);
259 test_addop_breakpoint(i, &p->aOp[i]);
260 }
261 #endif
262 #ifdef VDBE_PROFILE
263 pOp->cycles = 0;
264 pOp->cnt = 0;
265 #endif
266 #ifdef SQLITE_VDBE_COVERAGE
267 pOp->iSrcLine = 0;
268 #endif
269 return i;
270 }
sqlite3VdbeAddOp0(Vdbe * p,int op)271 int sqlite3VdbeAddOp0(Vdbe *p, int op){
272 return sqlite3VdbeAddOp3(p, op, 0, 0, 0);
273 }
sqlite3VdbeAddOp1(Vdbe * p,int op,int p1)274 int sqlite3VdbeAddOp1(Vdbe *p, int op, int p1){
275 return sqlite3VdbeAddOp3(p, op, p1, 0, 0);
276 }
sqlite3VdbeAddOp2(Vdbe * p,int op,int p1,int p2)277 int sqlite3VdbeAddOp2(Vdbe *p, int op, int p1, int p2){
278 return sqlite3VdbeAddOp3(p, op, p1, p2, 0);
279 }
280
281 /* Generate code for an unconditional jump to instruction iDest
282 */
sqlite3VdbeGoto(Vdbe * p,int iDest)283 int sqlite3VdbeGoto(Vdbe *p, int iDest){
284 return sqlite3VdbeAddOp3(p, OP_Goto, 0, iDest, 0);
285 }
286
287 /* Generate code to cause the string zStr to be loaded into
288 ** register iDest
289 */
sqlite3VdbeLoadString(Vdbe * p,int iDest,const char * zStr)290 int sqlite3VdbeLoadString(Vdbe *p, int iDest, const char *zStr){
291 return sqlite3VdbeAddOp4(p, OP_String8, 0, iDest, 0, zStr, 0);
292 }
293
294 /*
295 ** Generate code that initializes multiple registers to string or integer
296 ** constants. The registers begin with iDest and increase consecutively.
297 ** One register is initialized for each characgter in zTypes[]. For each
298 ** "s" character in zTypes[], the register is a string if the argument is
299 ** not NULL, or OP_Null if the value is a null pointer. For each "i" character
300 ** in zTypes[], the register is initialized to an integer.
301 **
302 ** If the input string does not end with "X" then an OP_ResultRow instruction
303 ** is generated for the values inserted.
304 */
sqlite3VdbeMultiLoad(Vdbe * p,int iDest,const char * zTypes,...)305 void sqlite3VdbeMultiLoad(Vdbe *p, int iDest, const char *zTypes, ...){
306 va_list ap;
307 int i;
308 char c;
309 va_start(ap, zTypes);
310 for(i=0; (c = zTypes[i])!=0; i++){
311 if( c=='s' ){
312 const char *z = va_arg(ap, const char*);
313 sqlite3VdbeAddOp4(p, z==0 ? OP_Null : OP_String8, 0, iDest+i, 0, z, 0);
314 }else if( c=='i' ){
315 sqlite3VdbeAddOp2(p, OP_Integer, va_arg(ap, int), iDest+i);
316 }else{
317 goto skip_op_resultrow;
318 }
319 }
320 sqlite3VdbeAddOp2(p, OP_ResultRow, iDest, i);
321 skip_op_resultrow:
322 va_end(ap);
323 }
324
325 /*
326 ** Add an opcode that includes the p4 value as a pointer.
327 */
sqlite3VdbeAddOp4(Vdbe * p,int op,int p1,int p2,int p3,const char * zP4,int p4type)328 int sqlite3VdbeAddOp4(
329 Vdbe *p, /* Add the opcode to this VM */
330 int op, /* The new opcode */
331 int p1, /* The P1 operand */
332 int p2, /* The P2 operand */
333 int p3, /* The P3 operand */
334 const char *zP4, /* The P4 operand */
335 int p4type /* P4 operand type */
336 ){
337 int addr = sqlite3VdbeAddOp3(p, op, p1, p2, p3);
338 sqlite3VdbeChangeP4(p, addr, zP4, p4type);
339 return addr;
340 }
341
342 /*
343 ** Add an OP_Function or OP_PureFunc opcode.
344 **
345 ** The eCallCtx argument is information (typically taken from Expr.op2)
346 ** that describes the calling context of the function. 0 means a general
347 ** function call. NC_IsCheck means called by a check constraint,
348 ** NC_IdxExpr means called as part of an index expression. NC_PartIdx
349 ** means in the WHERE clause of a partial index. NC_GenCol means called
350 ** while computing a generated column value. 0 is the usual case.
351 */
sqlite3VdbeAddFunctionCall(Parse * pParse,int p1,int p2,int p3,int nArg,const FuncDef * pFunc,int eCallCtx)352 int sqlite3VdbeAddFunctionCall(
353 Parse *pParse, /* Parsing context */
354 int p1, /* Constant argument mask */
355 int p2, /* First argument register */
356 int p3, /* Register into which results are written */
357 int nArg, /* Number of argument */
358 const FuncDef *pFunc, /* The function to be invoked */
359 int eCallCtx /* Calling context */
360 ){
361 Vdbe *v = pParse->pVdbe;
362 int nByte;
363 int addr;
364 sqlite3_context *pCtx;
365 assert( v );
366 nByte = sizeof(*pCtx) + (nArg-1)*sizeof(sqlite3_value*);
367 pCtx = sqlite3DbMallocRawNN(pParse->db, nByte);
368 if( pCtx==0 ){
369 assert( pParse->db->mallocFailed );
370 freeEphemeralFunction(pParse->db, (FuncDef*)pFunc);
371 return 0;
372 }
373 pCtx->pOut = 0;
374 pCtx->pFunc = (FuncDef*)pFunc;
375 pCtx->pVdbe = 0;
376 pCtx->isError = 0;
377 pCtx->argc = nArg;
378 pCtx->iOp = sqlite3VdbeCurrentAddr(v);
379 addr = sqlite3VdbeAddOp4(v, eCallCtx ? OP_PureFunc : OP_Function,
380 p1, p2, p3, (char*)pCtx, P4_FUNCCTX);
381 sqlite3VdbeChangeP5(v, eCallCtx & NC_SelfRef);
382 return addr;
383 }
384
385 /*
386 ** Add an opcode that includes the p4 value with a P4_INT64 or
387 ** P4_REAL type.
388 */
sqlite3VdbeAddOp4Dup8(Vdbe * p,int op,int p1,int p2,int p3,const u8 * zP4,int p4type)389 int sqlite3VdbeAddOp4Dup8(
390 Vdbe *p, /* Add the opcode to this VM */
391 int op, /* The new opcode */
392 int p1, /* The P1 operand */
393 int p2, /* The P2 operand */
394 int p3, /* The P3 operand */
395 const u8 *zP4, /* The P4 operand */
396 int p4type /* P4 operand type */
397 ){
398 char *p4copy = sqlite3DbMallocRawNN(sqlite3VdbeDb(p), 8);
399 if( p4copy ) memcpy(p4copy, zP4, 8);
400 return sqlite3VdbeAddOp4(p, op, p1, p2, p3, p4copy, p4type);
401 }
402
403 #ifndef SQLITE_OMIT_EXPLAIN
404 /*
405 ** Return the address of the current EXPLAIN QUERY PLAN baseline.
406 ** 0 means "none".
407 */
sqlite3VdbeExplainParent(Parse * pParse)408 int sqlite3VdbeExplainParent(Parse *pParse){
409 VdbeOp *pOp;
410 if( pParse->addrExplain==0 ) return 0;
411 pOp = sqlite3VdbeGetOp(pParse->pVdbe, pParse->addrExplain);
412 return pOp->p2;
413 }
414
415 /*
416 ** Set a debugger breakpoint on the following routine in order to
417 ** monitor the EXPLAIN QUERY PLAN code generation.
418 */
419 #if defined(SQLITE_DEBUG)
sqlite3ExplainBreakpoint(const char * z1,const char * z2)420 void sqlite3ExplainBreakpoint(const char *z1, const char *z2){
421 (void)z1;
422 (void)z2;
423 }
424 #endif
425
426 /*
427 ** Add a new OP_Explain opcode.
428 **
429 ** If the bPush flag is true, then make this opcode the parent for
430 ** subsequent Explains until sqlite3VdbeExplainPop() is called.
431 */
sqlite3VdbeExplain(Parse * pParse,u8 bPush,const char * zFmt,...)432 void sqlite3VdbeExplain(Parse *pParse, u8 bPush, const char *zFmt, ...){
433 #ifndef SQLITE_DEBUG
434 /* Always include the OP_Explain opcodes if SQLITE_DEBUG is defined.
435 ** But omit them (for performance) during production builds */
436 if( pParse->explain==2 )
437 #endif
438 {
439 char *zMsg;
440 Vdbe *v;
441 va_list ap;
442 int iThis;
443 va_start(ap, zFmt);
444 zMsg = sqlite3VMPrintf(pParse->db, zFmt, ap);
445 va_end(ap);
446 v = pParse->pVdbe;
447 iThis = v->nOp;
448 sqlite3VdbeAddOp4(v, OP_Explain, iThis, pParse->addrExplain, 0,
449 zMsg, P4_DYNAMIC);
450 sqlite3ExplainBreakpoint(bPush?"PUSH":"", sqlite3VdbeGetOp(v,-1)->p4.z);
451 if( bPush){
452 pParse->addrExplain = iThis;
453 }
454 }
455 }
456
457 /*
458 ** Pop the EXPLAIN QUERY PLAN stack one level.
459 */
sqlite3VdbeExplainPop(Parse * pParse)460 void sqlite3VdbeExplainPop(Parse *pParse){
461 sqlite3ExplainBreakpoint("POP", 0);
462 pParse->addrExplain = sqlite3VdbeExplainParent(pParse);
463 }
464 #endif /* SQLITE_OMIT_EXPLAIN */
465
466 /*
467 ** Add an OP_ParseSchema opcode. This routine is broken out from
468 ** sqlite3VdbeAddOp4() since it needs to also needs to mark all btrees
469 ** as having been used.
470 **
471 ** The zWhere string must have been obtained from sqlite3_malloc().
472 ** This routine will take ownership of the allocated memory.
473 */
sqlite3VdbeAddParseSchemaOp(Vdbe * p,int iDb,char * zWhere,u16 p5)474 void sqlite3VdbeAddParseSchemaOp(Vdbe *p, int iDb, char *zWhere, u16 p5){
475 int j;
476 sqlite3VdbeAddOp4(p, OP_ParseSchema, iDb, 0, 0, zWhere, P4_DYNAMIC);
477 sqlite3VdbeChangeP5(p, p5);
478 for(j=0; j<p->db->nDb; j++) sqlite3VdbeUsesBtree(p, j);
479 sqlite3MayAbort(p->pParse);
480 }
481
482 /*
483 ** Add an opcode that includes the p4 value as an integer.
484 */
sqlite3VdbeAddOp4Int(Vdbe * p,int op,int p1,int p2,int p3,int p4)485 int sqlite3VdbeAddOp4Int(
486 Vdbe *p, /* Add the opcode to this VM */
487 int op, /* The new opcode */
488 int p1, /* The P1 operand */
489 int p2, /* The P2 operand */
490 int p3, /* The P3 operand */
491 int p4 /* The P4 operand as an integer */
492 ){
493 int addr = sqlite3VdbeAddOp3(p, op, p1, p2, p3);
494 if( p->db->mallocFailed==0 ){
495 VdbeOp *pOp = &p->aOp[addr];
496 pOp->p4type = P4_INT32;
497 pOp->p4.i = p4;
498 }
499 return addr;
500 }
501
502 /* Insert the end of a co-routine
503 */
sqlite3VdbeEndCoroutine(Vdbe * v,int regYield)504 void sqlite3VdbeEndCoroutine(Vdbe *v, int regYield){
505 sqlite3VdbeAddOp1(v, OP_EndCoroutine, regYield);
506
507 /* Clear the temporary register cache, thereby ensuring that each
508 ** co-routine has its own independent set of registers, because co-routines
509 ** might expect their registers to be preserved across an OP_Yield, and
510 ** that could cause problems if two or more co-routines are using the same
511 ** temporary register.
512 */
513 v->pParse->nTempReg = 0;
514 v->pParse->nRangeReg = 0;
515 }
516
517 /*
518 ** Create a new symbolic label for an instruction that has yet to be
519 ** coded. The symbolic label is really just a negative number. The
520 ** label can be used as the P2 value of an operation. Later, when
521 ** the label is resolved to a specific address, the VDBE will scan
522 ** through its operation list and change all values of P2 which match
523 ** the label into the resolved address.
524 **
525 ** The VDBE knows that a P2 value is a label because labels are
526 ** always negative and P2 values are suppose to be non-negative.
527 ** Hence, a negative P2 value is a label that has yet to be resolved.
528 ** (Later:) This is only true for opcodes that have the OPFLG_JUMP
529 ** property.
530 **
531 ** Variable usage notes:
532 **
533 ** Parse.aLabel[x] Stores the address that the x-th label resolves
534 ** into. For testing (SQLITE_DEBUG), unresolved
535 ** labels stores -1, but that is not required.
536 ** Parse.nLabelAlloc Number of slots allocated to Parse.aLabel[]
537 ** Parse.nLabel The *negative* of the number of labels that have
538 ** been issued. The negative is stored because
539 ** that gives a performance improvement over storing
540 ** the equivalent positive value.
541 */
sqlite3VdbeMakeLabel(Parse * pParse)542 int sqlite3VdbeMakeLabel(Parse *pParse){
543 return --pParse->nLabel;
544 }
545
546 /*
547 ** Resolve label "x" to be the address of the next instruction to
548 ** be inserted. The parameter "x" must have been obtained from
549 ** a prior call to sqlite3VdbeMakeLabel().
550 */
resizeResolveLabel(Parse * p,Vdbe * v,int j)551 static SQLITE_NOINLINE void resizeResolveLabel(Parse *p, Vdbe *v, int j){
552 int nNewSize = 10 - p->nLabel;
553 p->aLabel = sqlite3DbReallocOrFree(p->db, p->aLabel,
554 nNewSize*sizeof(p->aLabel[0]));
555 if( p->aLabel==0 ){
556 p->nLabelAlloc = 0;
557 }else{
558 #ifdef SQLITE_DEBUG
559 int i;
560 for(i=p->nLabelAlloc; i<nNewSize; i++) p->aLabel[i] = -1;
561 #endif
562 p->nLabelAlloc = nNewSize;
563 p->aLabel[j] = v->nOp;
564 }
565 }
sqlite3VdbeResolveLabel(Vdbe * v,int x)566 void sqlite3VdbeResolveLabel(Vdbe *v, int x){
567 Parse *p = v->pParse;
568 int j = ADDR(x);
569 assert( v->iVdbeMagic==VDBE_MAGIC_INIT );
570 assert( j<-p->nLabel );
571 assert( j>=0 );
572 #ifdef SQLITE_DEBUG
573 if( p->db->flags & SQLITE_VdbeAddopTrace ){
574 printf("RESOLVE LABEL %d to %d\n", x, v->nOp);
575 }
576 #endif
577 if( p->nLabelAlloc + p->nLabel < 0 ){
578 resizeResolveLabel(p,v,j);
579 }else{
580 assert( p->aLabel[j]==(-1) ); /* Labels may only be resolved once */
581 p->aLabel[j] = v->nOp;
582 }
583 }
584
585 /*
586 ** Mark the VDBE as one that can only be run one time.
587 */
sqlite3VdbeRunOnlyOnce(Vdbe * p)588 void sqlite3VdbeRunOnlyOnce(Vdbe *p){
589 p->runOnlyOnce = 1;
590 }
591
592 /*
593 ** Mark the VDBE as one that can only be run multiple times.
594 */
sqlite3VdbeReusable(Vdbe * p)595 void sqlite3VdbeReusable(Vdbe *p){
596 p->runOnlyOnce = 0;
597 }
598
599 #ifdef SQLITE_DEBUG /* sqlite3AssertMayAbort() logic */
600
601 /*
602 ** The following type and function are used to iterate through all opcodes
603 ** in a Vdbe main program and each of the sub-programs (triggers) it may
604 ** invoke directly or indirectly. It should be used as follows:
605 **
606 ** Op *pOp;
607 ** VdbeOpIter sIter;
608 **
609 ** memset(&sIter, 0, sizeof(sIter));
610 ** sIter.v = v; // v is of type Vdbe*
611 ** while( (pOp = opIterNext(&sIter)) ){
612 ** // Do something with pOp
613 ** }
614 ** sqlite3DbFree(v->db, sIter.apSub);
615 **
616 */
617 typedef struct VdbeOpIter VdbeOpIter;
618 struct VdbeOpIter {
619 Vdbe *v; /* Vdbe to iterate through the opcodes of */
620 SubProgram **apSub; /* Array of subprograms */
621 int nSub; /* Number of entries in apSub */
622 int iAddr; /* Address of next instruction to return */
623 int iSub; /* 0 = main program, 1 = first sub-program etc. */
624 };
opIterNext(VdbeOpIter * p)625 static Op *opIterNext(VdbeOpIter *p){
626 Vdbe *v = p->v;
627 Op *pRet = 0;
628 Op *aOp;
629 int nOp;
630
631 if( p->iSub<=p->nSub ){
632
633 if( p->iSub==0 ){
634 aOp = v->aOp;
635 nOp = v->nOp;
636 }else{
637 aOp = p->apSub[p->iSub-1]->aOp;
638 nOp = p->apSub[p->iSub-1]->nOp;
639 }
640 assert( p->iAddr<nOp );
641
642 pRet = &aOp[p->iAddr];
643 p->iAddr++;
644 if( p->iAddr==nOp ){
645 p->iSub++;
646 p->iAddr = 0;
647 }
648
649 if( pRet->p4type==P4_SUBPROGRAM ){
650 int nByte = (p->nSub+1)*sizeof(SubProgram*);
651 int j;
652 for(j=0; j<p->nSub; j++){
653 if( p->apSub[j]==pRet->p4.pProgram ) break;
654 }
655 if( j==p->nSub ){
656 p->apSub = sqlite3DbReallocOrFree(v->db, p->apSub, nByte);
657 if( !p->apSub ){
658 pRet = 0;
659 }else{
660 p->apSub[p->nSub++] = pRet->p4.pProgram;
661 }
662 }
663 }
664 }
665
666 return pRet;
667 }
668
669 /*
670 ** Check if the program stored in the VM associated with pParse may
671 ** throw an ABORT exception (causing the statement, but not entire transaction
672 ** to be rolled back). This condition is true if the main program or any
673 ** sub-programs contains any of the following:
674 **
675 ** * OP_Halt with P1=SQLITE_CONSTRAINT and P2=OE_Abort.
676 ** * OP_HaltIfNull with P1=SQLITE_CONSTRAINT and P2=OE_Abort.
677 ** * OP_Destroy
678 ** * OP_VUpdate
679 ** * OP_VCreate
680 ** * OP_VRename
681 ** * OP_FkCounter with P2==0 (immediate foreign key constraint)
682 ** * OP_CreateBtree/BTREE_INTKEY and OP_InitCoroutine
683 ** (for CREATE TABLE AS SELECT ...)
684 **
685 ** Then check that the value of Parse.mayAbort is true if an
686 ** ABORT may be thrown, or false otherwise. Return true if it does
687 ** match, or false otherwise. This function is intended to be used as
688 ** part of an assert statement in the compiler. Similar to:
689 **
690 ** assert( sqlite3VdbeAssertMayAbort(pParse->pVdbe, pParse->mayAbort) );
691 */
sqlite3VdbeAssertMayAbort(Vdbe * v,int mayAbort)692 int sqlite3VdbeAssertMayAbort(Vdbe *v, int mayAbort){
693 int hasAbort = 0;
694 int hasFkCounter = 0;
695 int hasCreateTable = 0;
696 int hasCreateIndex = 0;
697 int hasInitCoroutine = 0;
698 Op *pOp;
699 VdbeOpIter sIter;
700 memset(&sIter, 0, sizeof(sIter));
701 sIter.v = v;
702
703 while( (pOp = opIterNext(&sIter))!=0 ){
704 int opcode = pOp->opcode;
705 if( opcode==OP_Destroy || opcode==OP_VUpdate || opcode==OP_VRename
706 || opcode==OP_VDestroy
707 || opcode==OP_VCreate
708 || opcode==OP_ParseSchema
709 || ((opcode==OP_Halt || opcode==OP_HaltIfNull)
710 && ((pOp->p1)!=SQLITE_OK && pOp->p2==OE_Abort))
711 ){
712 hasAbort = 1;
713 break;
714 }
715 if( opcode==OP_CreateBtree && pOp->p3==BTREE_INTKEY ) hasCreateTable = 1;
716 if( mayAbort ){
717 /* hasCreateIndex may also be set for some DELETE statements that use
718 ** OP_Clear. So this routine may end up returning true in the case
719 ** where a "DELETE FROM tbl" has a statement-journal but does not
720 ** require one. This is not so bad - it is an inefficiency, not a bug. */
721 if( opcode==OP_CreateBtree && pOp->p3==BTREE_BLOBKEY ) hasCreateIndex = 1;
722 if( opcode==OP_Clear ) hasCreateIndex = 1;
723 }
724 if( opcode==OP_InitCoroutine ) hasInitCoroutine = 1;
725 #ifndef SQLITE_OMIT_FOREIGN_KEY
726 if( opcode==OP_FkCounter && pOp->p1==0 && pOp->p2==1 ){
727 hasFkCounter = 1;
728 }
729 #endif
730 }
731 sqlite3DbFree(v->db, sIter.apSub);
732
733 /* Return true if hasAbort==mayAbort. Or if a malloc failure occurred.
734 ** If malloc failed, then the while() loop above may not have iterated
735 ** through all opcodes and hasAbort may be set incorrectly. Return
736 ** true for this case to prevent the assert() in the callers frame
737 ** from failing. */
738 return ( v->db->mallocFailed || hasAbort==mayAbort || hasFkCounter
739 || (hasCreateTable && hasInitCoroutine) || hasCreateIndex
740 );
741 }
742 #endif /* SQLITE_DEBUG - the sqlite3AssertMayAbort() function */
743
744 #ifdef SQLITE_DEBUG
745 /*
746 ** Increment the nWrite counter in the VDBE if the cursor is not an
747 ** ephemeral cursor, or if the cursor argument is NULL.
748 */
sqlite3VdbeIncrWriteCounter(Vdbe * p,VdbeCursor * pC)749 void sqlite3VdbeIncrWriteCounter(Vdbe *p, VdbeCursor *pC){
750 if( pC==0
751 || (pC->eCurType!=CURTYPE_SORTER
752 && pC->eCurType!=CURTYPE_PSEUDO
753 && !pC->isEphemeral)
754 ){
755 p->nWrite++;
756 }
757 }
758 #endif
759
760 #ifdef SQLITE_DEBUG
761 /*
762 ** Assert if an Abort at this point in time might result in a corrupt
763 ** database.
764 */
sqlite3VdbeAssertAbortable(Vdbe * p)765 void sqlite3VdbeAssertAbortable(Vdbe *p){
766 assert( p->nWrite==0 || p->usesStmtJournal );
767 }
768 #endif
769
770 /*
771 ** This routine is called after all opcodes have been inserted. It loops
772 ** through all the opcodes and fixes up some details.
773 **
774 ** (1) For each jump instruction with a negative P2 value (a label)
775 ** resolve the P2 value to an actual address.
776 **
777 ** (2) Compute the maximum number of arguments used by any SQL function
778 ** and store that value in *pMaxFuncArgs.
779 **
780 ** (3) Update the Vdbe.readOnly and Vdbe.bIsReader flags to accurately
781 ** indicate what the prepared statement actually does.
782 **
783 ** (4) Initialize the p4.xAdvance pointer on opcodes that use it.
784 **
785 ** (5) Reclaim the memory allocated for storing labels.
786 **
787 ** This routine will only function correctly if the mkopcodeh.tcl generator
788 ** script numbers the opcodes correctly. Changes to this routine must be
789 ** coordinated with changes to mkopcodeh.tcl.
790 */
resolveP2Values(Vdbe * p,int * pMaxFuncArgs)791 static void resolveP2Values(Vdbe *p, int *pMaxFuncArgs){
792 int nMaxArgs = *pMaxFuncArgs;
793 Op *pOp;
794 Parse *pParse = p->pParse;
795 int *aLabel = pParse->aLabel;
796 p->readOnly = 1;
797 p->bIsReader = 0;
798 pOp = &p->aOp[p->nOp-1];
799 while(1){
800
801 /* Only JUMP opcodes and the short list of special opcodes in the switch
802 ** below need to be considered. The mkopcodeh.tcl generator script groups
803 ** all these opcodes together near the front of the opcode list. Skip
804 ** any opcode that does not need processing by virtual of the fact that
805 ** it is larger than SQLITE_MX_JUMP_OPCODE, as a performance optimization.
806 */
807 if( pOp->opcode<=SQLITE_MX_JUMP_OPCODE ){
808 /* NOTE: Be sure to update mkopcodeh.tcl when adding or removing
809 ** cases from this switch! */
810 switch( pOp->opcode ){
811 case OP_Transaction: {
812 if( pOp->p2!=0 ) p->readOnly = 0;
813 /* no break */ deliberate_fall_through
814 }
815 case OP_AutoCommit:
816 case OP_Savepoint: {
817 p->bIsReader = 1;
818 break;
819 }
820 #ifndef SQLITE_OMIT_WAL
821 case OP_Checkpoint:
822 #endif
823 case OP_Vacuum:
824 case OP_JournalMode: {
825 p->readOnly = 0;
826 p->bIsReader = 1;
827 break;
828 }
829 case OP_Next:
830 case OP_SorterNext: {
831 pOp->p4.xAdvance = sqlite3BtreeNext;
832 pOp->p4type = P4_ADVANCE;
833 /* The code generator never codes any of these opcodes as a jump
834 ** to a label. They are always coded as a jump backwards to a
835 ** known address */
836 assert( pOp->p2>=0 );
837 break;
838 }
839 case OP_Prev: {
840 pOp->p4.xAdvance = sqlite3BtreePrevious;
841 pOp->p4type = P4_ADVANCE;
842 /* The code generator never codes any of these opcodes as a jump
843 ** to a label. They are always coded as a jump backwards to a
844 ** known address */
845 assert( pOp->p2>=0 );
846 break;
847 }
848 #ifndef SQLITE_OMIT_VIRTUALTABLE
849 case OP_VUpdate: {
850 if( pOp->p2>nMaxArgs ) nMaxArgs = pOp->p2;
851 break;
852 }
853 case OP_VFilter: {
854 int n;
855 assert( (pOp - p->aOp) >= 3 );
856 assert( pOp[-1].opcode==OP_Integer );
857 n = pOp[-1].p1;
858 if( n>nMaxArgs ) nMaxArgs = n;
859 /* Fall through into the default case */
860 /* no break */ deliberate_fall_through
861 }
862 #endif
863 default: {
864 if( pOp->p2<0 ){
865 /* The mkopcodeh.tcl script has so arranged things that the only
866 ** non-jump opcodes less than SQLITE_MX_JUMP_CODE are guaranteed to
867 ** have non-negative values for P2. */
868 assert( (sqlite3OpcodeProperty[pOp->opcode] & OPFLG_JUMP)!=0 );
869 assert( ADDR(pOp->p2)<-pParse->nLabel );
870 pOp->p2 = aLabel[ADDR(pOp->p2)];
871 }
872 break;
873 }
874 }
875 /* The mkopcodeh.tcl script has so arranged things that the only
876 ** non-jump opcodes less than SQLITE_MX_JUMP_CODE are guaranteed to
877 ** have non-negative values for P2. */
878 assert( (sqlite3OpcodeProperty[pOp->opcode]&OPFLG_JUMP)==0 || pOp->p2>=0);
879 }
880 if( pOp==p->aOp ) break;
881 pOp--;
882 }
883 sqlite3DbFree(p->db, pParse->aLabel);
884 pParse->aLabel = 0;
885 pParse->nLabel = 0;
886 *pMaxFuncArgs = nMaxArgs;
887 assert( p->bIsReader!=0 || DbMaskAllZero(p->btreeMask) );
888 }
889
890 /*
891 ** Return the address of the next instruction to be inserted.
892 */
sqlite3VdbeCurrentAddr(Vdbe * p)893 int sqlite3VdbeCurrentAddr(Vdbe *p){
894 assert( p->iVdbeMagic==VDBE_MAGIC_INIT );
895 return p->nOp;
896 }
897
898 /*
899 ** Verify that at least N opcode slots are available in p without
900 ** having to malloc for more space (except when compiled using
901 ** SQLITE_TEST_REALLOC_STRESS). This interface is used during testing
902 ** to verify that certain calls to sqlite3VdbeAddOpList() can never
903 ** fail due to a OOM fault and hence that the return value from
904 ** sqlite3VdbeAddOpList() will always be non-NULL.
905 */
906 #if defined(SQLITE_DEBUG) && !defined(SQLITE_TEST_REALLOC_STRESS)
sqlite3VdbeVerifyNoMallocRequired(Vdbe * p,int N)907 void sqlite3VdbeVerifyNoMallocRequired(Vdbe *p, int N){
908 assert( p->nOp + N <= p->nOpAlloc );
909 }
910 #endif
911
912 /*
913 ** Verify that the VM passed as the only argument does not contain
914 ** an OP_ResultRow opcode. Fail an assert() if it does. This is used
915 ** by code in pragma.c to ensure that the implementation of certain
916 ** pragmas comports with the flags specified in the mkpragmatab.tcl
917 ** script.
918 */
919 #if defined(SQLITE_DEBUG) && !defined(SQLITE_TEST_REALLOC_STRESS)
sqlite3VdbeVerifyNoResultRow(Vdbe * p)920 void sqlite3VdbeVerifyNoResultRow(Vdbe *p){
921 int i;
922 for(i=0; i<p->nOp; i++){
923 assert( p->aOp[i].opcode!=OP_ResultRow );
924 }
925 }
926 #endif
927
928 /*
929 ** Generate code (a single OP_Abortable opcode) that will
930 ** verify that the VDBE program can safely call Abort in the current
931 ** context.
932 */
933 #if defined(SQLITE_DEBUG)
sqlite3VdbeVerifyAbortable(Vdbe * p,int onError)934 void sqlite3VdbeVerifyAbortable(Vdbe *p, int onError){
935 if( onError==OE_Abort ) sqlite3VdbeAddOp0(p, OP_Abortable);
936 }
937 #endif
938
939 /*
940 ** This function returns a pointer to the array of opcodes associated with
941 ** the Vdbe passed as the first argument. It is the callers responsibility
942 ** to arrange for the returned array to be eventually freed using the
943 ** vdbeFreeOpArray() function.
944 **
945 ** Before returning, *pnOp is set to the number of entries in the returned
946 ** array. Also, *pnMaxArg is set to the larger of its current value and
947 ** the number of entries in the Vdbe.apArg[] array required to execute the
948 ** returned program.
949 */
sqlite3VdbeTakeOpArray(Vdbe * p,int * pnOp,int * pnMaxArg)950 VdbeOp *sqlite3VdbeTakeOpArray(Vdbe *p, int *pnOp, int *pnMaxArg){
951 VdbeOp *aOp = p->aOp;
952 assert( aOp && !p->db->mallocFailed );
953
954 /* Check that sqlite3VdbeUsesBtree() was not called on this VM */
955 assert( DbMaskAllZero(p->btreeMask) );
956
957 resolveP2Values(p, pnMaxArg);
958 *pnOp = p->nOp;
959 p->aOp = 0;
960 return aOp;
961 }
962
963 /*
964 ** Add a whole list of operations to the operation stack. Return a
965 ** pointer to the first operation inserted.
966 **
967 ** Non-zero P2 arguments to jump instructions are automatically adjusted
968 ** so that the jump target is relative to the first operation inserted.
969 */
sqlite3VdbeAddOpList(Vdbe * p,int nOp,VdbeOpList const * aOp,int iLineno)970 VdbeOp *sqlite3VdbeAddOpList(
971 Vdbe *p, /* Add opcodes to the prepared statement */
972 int nOp, /* Number of opcodes to add */
973 VdbeOpList const *aOp, /* The opcodes to be added */
974 int iLineno /* Source-file line number of first opcode */
975 ){
976 int i;
977 VdbeOp *pOut, *pFirst;
978 assert( nOp>0 );
979 assert( p->iVdbeMagic==VDBE_MAGIC_INIT );
980 if( p->nOp + nOp > p->nOpAlloc && growOpArray(p, nOp) ){
981 return 0;
982 }
983 pFirst = pOut = &p->aOp[p->nOp];
984 for(i=0; i<nOp; i++, aOp++, pOut++){
985 pOut->opcode = aOp->opcode;
986 pOut->p1 = aOp->p1;
987 pOut->p2 = aOp->p2;
988 assert( aOp->p2>=0 );
989 if( (sqlite3OpcodeProperty[aOp->opcode] & OPFLG_JUMP)!=0 && aOp->p2>0 ){
990 pOut->p2 += p->nOp;
991 }
992 pOut->p3 = aOp->p3;
993 pOut->p4type = P4_NOTUSED;
994 pOut->p4.p = 0;
995 pOut->p5 = 0;
996 #ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
997 pOut->zComment = 0;
998 #endif
999 #ifdef SQLITE_VDBE_COVERAGE
1000 pOut->iSrcLine = iLineno+i;
1001 #else
1002 (void)iLineno;
1003 #endif
1004 #ifdef SQLITE_DEBUG
1005 if( p->db->flags & SQLITE_VdbeAddopTrace ){
1006 sqlite3VdbePrintOp(0, i+p->nOp, &p->aOp[i+p->nOp]);
1007 }
1008 #endif
1009 }
1010 p->nOp += nOp;
1011 return pFirst;
1012 }
1013
1014 #if defined(SQLITE_ENABLE_STMT_SCANSTATUS)
1015 /*
1016 ** Add an entry to the array of counters managed by sqlite3_stmt_scanstatus().
1017 */
sqlite3VdbeScanStatus(Vdbe * p,int addrExplain,int addrLoop,int addrVisit,LogEst nEst,const char * zName)1018 void sqlite3VdbeScanStatus(
1019 Vdbe *p, /* VM to add scanstatus() to */
1020 int addrExplain, /* Address of OP_Explain (or 0) */
1021 int addrLoop, /* Address of loop counter */
1022 int addrVisit, /* Address of rows visited counter */
1023 LogEst nEst, /* Estimated number of output rows */
1024 const char *zName /* Name of table or index being scanned */
1025 ){
1026 sqlite3_int64 nByte = (p->nScan+1) * sizeof(ScanStatus);
1027 ScanStatus *aNew;
1028 aNew = (ScanStatus*)sqlite3DbRealloc(p->db, p->aScan, nByte);
1029 if( aNew ){
1030 ScanStatus *pNew = &aNew[p->nScan++];
1031 pNew->addrExplain = addrExplain;
1032 pNew->addrLoop = addrLoop;
1033 pNew->addrVisit = addrVisit;
1034 pNew->nEst = nEst;
1035 pNew->zName = sqlite3DbStrDup(p->db, zName);
1036 p->aScan = aNew;
1037 }
1038 }
1039 #endif
1040
1041
1042 /*
1043 ** Change the value of the opcode, or P1, P2, P3, or P5 operands
1044 ** for a specific instruction.
1045 */
sqlite3VdbeChangeOpcode(Vdbe * p,int addr,u8 iNewOpcode)1046 void sqlite3VdbeChangeOpcode(Vdbe *p, int addr, u8 iNewOpcode){
1047 sqlite3VdbeGetOp(p,addr)->opcode = iNewOpcode;
1048 }
sqlite3VdbeChangeP1(Vdbe * p,int addr,int val)1049 void sqlite3VdbeChangeP1(Vdbe *p, int addr, int val){
1050 sqlite3VdbeGetOp(p,addr)->p1 = val;
1051 }
sqlite3VdbeChangeP2(Vdbe * p,int addr,int val)1052 void sqlite3VdbeChangeP2(Vdbe *p, int addr, int val){
1053 sqlite3VdbeGetOp(p,addr)->p2 = val;
1054 }
sqlite3VdbeChangeP3(Vdbe * p,int addr,int val)1055 void sqlite3VdbeChangeP3(Vdbe *p, int addr, int val){
1056 sqlite3VdbeGetOp(p,addr)->p3 = val;
1057 }
sqlite3VdbeChangeP5(Vdbe * p,u16 p5)1058 void sqlite3VdbeChangeP5(Vdbe *p, u16 p5){
1059 assert( p->nOp>0 || p->db->mallocFailed );
1060 if( p->nOp>0 ) p->aOp[p->nOp-1].p5 = p5;
1061 }
1062
1063 /*
1064 ** Change the P2 operand of instruction addr so that it points to
1065 ** the address of the next instruction to be coded.
1066 */
sqlite3VdbeJumpHere(Vdbe * p,int addr)1067 void sqlite3VdbeJumpHere(Vdbe *p, int addr){
1068 sqlite3VdbeChangeP2(p, addr, p->nOp);
1069 }
1070
1071 /*
1072 ** Change the P2 operand of the jump instruction at addr so that
1073 ** the jump lands on the next opcode. Or if the jump instruction was
1074 ** the previous opcode (and is thus a no-op) then simply back up
1075 ** the next instruction counter by one slot so that the jump is
1076 ** overwritten by the next inserted opcode.
1077 **
1078 ** This routine is an optimization of sqlite3VdbeJumpHere() that
1079 ** strives to omit useless byte-code like this:
1080 **
1081 ** 7 Once 0 8 0
1082 ** 8 ...
1083 */
sqlite3VdbeJumpHereOrPopInst(Vdbe * p,int addr)1084 void sqlite3VdbeJumpHereOrPopInst(Vdbe *p, int addr){
1085 if( addr==p->nOp-1 ){
1086 assert( p->aOp[addr].opcode==OP_Once
1087 || p->aOp[addr].opcode==OP_If
1088 || p->aOp[addr].opcode==OP_FkIfZero );
1089 assert( p->aOp[addr].p4type==0 );
1090 #ifdef SQLITE_VDBE_COVERAGE
1091 sqlite3VdbeGetOp(p,-1)->iSrcLine = 0; /* Erase VdbeCoverage() macros */
1092 #endif
1093 p->nOp--;
1094 }else{
1095 sqlite3VdbeChangeP2(p, addr, p->nOp);
1096 }
1097 }
1098
1099
1100 /*
1101 ** If the input FuncDef structure is ephemeral, then free it. If
1102 ** the FuncDef is not ephermal, then do nothing.
1103 */
freeEphemeralFunction(sqlite3 * db,FuncDef * pDef)1104 static void freeEphemeralFunction(sqlite3 *db, FuncDef *pDef){
1105 if( (pDef->funcFlags & SQLITE_FUNC_EPHEM)!=0 ){
1106 sqlite3DbFreeNN(db, pDef);
1107 }
1108 }
1109
1110 /*
1111 ** Delete a P4 value if necessary.
1112 */
freeP4Mem(sqlite3 * db,Mem * p)1113 static SQLITE_NOINLINE void freeP4Mem(sqlite3 *db, Mem *p){
1114 if( p->szMalloc ) sqlite3DbFree(db, p->zMalloc);
1115 sqlite3DbFreeNN(db, p);
1116 }
freeP4FuncCtx(sqlite3 * db,sqlite3_context * p)1117 static SQLITE_NOINLINE void freeP4FuncCtx(sqlite3 *db, sqlite3_context *p){
1118 freeEphemeralFunction(db, p->pFunc);
1119 sqlite3DbFreeNN(db, p);
1120 }
freeP4(sqlite3 * db,int p4type,void * p4)1121 static void freeP4(sqlite3 *db, int p4type, void *p4){
1122 assert( db );
1123 switch( p4type ){
1124 case P4_FUNCCTX: {
1125 freeP4FuncCtx(db, (sqlite3_context*)p4);
1126 break;
1127 }
1128 case P4_REAL:
1129 case P4_INT64:
1130 case P4_DYNAMIC:
1131 case P4_DYNBLOB:
1132 case P4_INTARRAY: {
1133 sqlite3DbFree(db, p4);
1134 break;
1135 }
1136 case P4_KEYINFO: {
1137 if( db->pnBytesFreed==0 ) sqlite3KeyInfoUnref((KeyInfo*)p4);
1138 break;
1139 }
1140 #ifdef SQLITE_ENABLE_CURSOR_HINTS
1141 case P4_EXPR: {
1142 sqlite3ExprDelete(db, (Expr*)p4);
1143 break;
1144 }
1145 #endif
1146 case P4_FUNCDEF: {
1147 freeEphemeralFunction(db, (FuncDef*)p4);
1148 break;
1149 }
1150 case P4_MEM: {
1151 if( db->pnBytesFreed==0 ){
1152 sqlite3ValueFree((sqlite3_value*)p4);
1153 }else{
1154 freeP4Mem(db, (Mem*)p4);
1155 }
1156 break;
1157 }
1158 case P4_VTAB : {
1159 if( db->pnBytesFreed==0 ) sqlite3VtabUnlock((VTable *)p4);
1160 break;
1161 }
1162 }
1163 }
1164
1165 /*
1166 ** Free the space allocated for aOp and any p4 values allocated for the
1167 ** opcodes contained within. If aOp is not NULL it is assumed to contain
1168 ** nOp entries.
1169 */
vdbeFreeOpArray(sqlite3 * db,Op * aOp,int nOp)1170 static void vdbeFreeOpArray(sqlite3 *db, Op *aOp, int nOp){
1171 if( aOp ){
1172 Op *pOp;
1173 for(pOp=&aOp[nOp-1]; pOp>=aOp; pOp--){
1174 if( pOp->p4type <= P4_FREE_IF_LE ) freeP4(db, pOp->p4type, pOp->p4.p);
1175 #ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
1176 sqlite3DbFree(db, pOp->zComment);
1177 #endif
1178 }
1179 sqlite3DbFreeNN(db, aOp);
1180 }
1181 }
1182
1183 /*
1184 ** Link the SubProgram object passed as the second argument into the linked
1185 ** list at Vdbe.pSubProgram. This list is used to delete all sub-program
1186 ** objects when the VM is no longer required.
1187 */
sqlite3VdbeLinkSubProgram(Vdbe * pVdbe,SubProgram * p)1188 void sqlite3VdbeLinkSubProgram(Vdbe *pVdbe, SubProgram *p){
1189 p->pNext = pVdbe->pProgram;
1190 pVdbe->pProgram = p;
1191 }
1192
1193 /*
1194 ** Return true if the given Vdbe has any SubPrograms.
1195 */
sqlite3VdbeHasSubProgram(Vdbe * pVdbe)1196 int sqlite3VdbeHasSubProgram(Vdbe *pVdbe){
1197 return pVdbe->pProgram!=0;
1198 }
1199
1200 /*
1201 ** Change the opcode at addr into OP_Noop
1202 */
sqlite3VdbeChangeToNoop(Vdbe * p,int addr)1203 int sqlite3VdbeChangeToNoop(Vdbe *p, int addr){
1204 VdbeOp *pOp;
1205 if( p->db->mallocFailed ) return 0;
1206 assert( addr>=0 && addr<p->nOp );
1207 pOp = &p->aOp[addr];
1208 freeP4(p->db, pOp->p4type, pOp->p4.p);
1209 pOp->p4type = P4_NOTUSED;
1210 pOp->p4.z = 0;
1211 pOp->opcode = OP_Noop;
1212 return 1;
1213 }
1214
1215 /*
1216 ** If the last opcode is "op" and it is not a jump destination,
1217 ** then remove it. Return true if and only if an opcode was removed.
1218 */
sqlite3VdbeDeletePriorOpcode(Vdbe * p,u8 op)1219 int sqlite3VdbeDeletePriorOpcode(Vdbe *p, u8 op){
1220 if( p->nOp>0 && p->aOp[p->nOp-1].opcode==op ){
1221 return sqlite3VdbeChangeToNoop(p, p->nOp-1);
1222 }else{
1223 return 0;
1224 }
1225 }
1226
1227 #ifdef SQLITE_DEBUG
1228 /*
1229 ** Generate an OP_ReleaseReg opcode to indicate that a range of
1230 ** registers, except any identified by mask, are no longer in use.
1231 */
sqlite3VdbeReleaseRegisters(Parse * pParse,int iFirst,int N,u32 mask,int bUndefine)1232 void sqlite3VdbeReleaseRegisters(
1233 Parse *pParse, /* Parsing context */
1234 int iFirst, /* Index of first register to be released */
1235 int N, /* Number of registers to release */
1236 u32 mask, /* Mask of registers to NOT release */
1237 int bUndefine /* If true, mark registers as undefined */
1238 ){
1239 if( N==0 ) return;
1240 assert( pParse->pVdbe );
1241 assert( iFirst>=1 );
1242 assert( iFirst+N-1<=pParse->nMem );
1243 if( N<=31 && mask!=0 ){
1244 while( N>0 && (mask&1)!=0 ){
1245 mask >>= 1;
1246 iFirst++;
1247 N--;
1248 }
1249 while( N>0 && N<=32 && (mask & MASKBIT32(N-1))!=0 ){
1250 mask &= ~MASKBIT32(N-1);
1251 N--;
1252 }
1253 }
1254 if( N>0 ){
1255 sqlite3VdbeAddOp3(pParse->pVdbe, OP_ReleaseReg, iFirst, N, *(int*)&mask);
1256 if( bUndefine ) sqlite3VdbeChangeP5(pParse->pVdbe, 1);
1257 }
1258 }
1259 #endif /* SQLITE_DEBUG */
1260
1261
1262 /*
1263 ** Change the value of the P4 operand for a specific instruction.
1264 ** This routine is useful when a large program is loaded from a
1265 ** static array using sqlite3VdbeAddOpList but we want to make a
1266 ** few minor changes to the program.
1267 **
1268 ** If n>=0 then the P4 operand is dynamic, meaning that a copy of
1269 ** the string is made into memory obtained from sqlite3_malloc().
1270 ** A value of n==0 means copy bytes of zP4 up to and including the
1271 ** first null byte. If n>0 then copy n+1 bytes of zP4.
1272 **
1273 ** Other values of n (P4_STATIC, P4_COLLSEQ etc.) indicate that zP4 points
1274 ** to a string or structure that is guaranteed to exist for the lifetime of
1275 ** the Vdbe. In these cases we can just copy the pointer.
1276 **
1277 ** If addr<0 then change P4 on the most recently inserted instruction.
1278 */
vdbeChangeP4Full(Vdbe * p,Op * pOp,const char * zP4,int n)1279 static void SQLITE_NOINLINE vdbeChangeP4Full(
1280 Vdbe *p,
1281 Op *pOp,
1282 const char *zP4,
1283 int n
1284 ){
1285 if( pOp->p4type ){
1286 freeP4(p->db, pOp->p4type, pOp->p4.p);
1287 pOp->p4type = 0;
1288 pOp->p4.p = 0;
1289 }
1290 if( n<0 ){
1291 sqlite3VdbeChangeP4(p, (int)(pOp - p->aOp), zP4, n);
1292 }else{
1293 if( n==0 ) n = sqlite3Strlen30(zP4);
1294 pOp->p4.z = sqlite3DbStrNDup(p->db, zP4, n);
1295 pOp->p4type = P4_DYNAMIC;
1296 }
1297 }
sqlite3VdbeChangeP4(Vdbe * p,int addr,const char * zP4,int n)1298 void sqlite3VdbeChangeP4(Vdbe *p, int addr, const char *zP4, int n){
1299 Op *pOp;
1300 sqlite3 *db;
1301 assert( p!=0 );
1302 db = p->db;
1303 assert( p->iVdbeMagic==VDBE_MAGIC_INIT );
1304 assert( p->aOp!=0 || db->mallocFailed );
1305 if( db->mallocFailed ){
1306 if( n!=P4_VTAB ) freeP4(db, n, (void*)*(char**)&zP4);
1307 return;
1308 }
1309 assert( p->nOp>0 );
1310 assert( addr<p->nOp );
1311 if( addr<0 ){
1312 addr = p->nOp - 1;
1313 }
1314 pOp = &p->aOp[addr];
1315 if( n>=0 || pOp->p4type ){
1316 vdbeChangeP4Full(p, pOp, zP4, n);
1317 return;
1318 }
1319 if( n==P4_INT32 ){
1320 /* Note: this cast is safe, because the origin data point was an int
1321 ** that was cast to a (const char *). */
1322 pOp->p4.i = SQLITE_PTR_TO_INT(zP4);
1323 pOp->p4type = P4_INT32;
1324 }else if( zP4!=0 ){
1325 assert( n<0 );
1326 pOp->p4.p = (void*)zP4;
1327 pOp->p4type = (signed char)n;
1328 if( n==P4_VTAB ) sqlite3VtabLock((VTable*)zP4);
1329 }
1330 }
1331
1332 /*
1333 ** Change the P4 operand of the most recently coded instruction
1334 ** to the value defined by the arguments. This is a high-speed
1335 ** version of sqlite3VdbeChangeP4().
1336 **
1337 ** The P4 operand must not have been previously defined. And the new
1338 ** P4 must not be P4_INT32. Use sqlite3VdbeChangeP4() in either of
1339 ** those cases.
1340 */
sqlite3VdbeAppendP4(Vdbe * p,void * pP4,int n)1341 void sqlite3VdbeAppendP4(Vdbe *p, void *pP4, int n){
1342 VdbeOp *pOp;
1343 assert( n!=P4_INT32 && n!=P4_VTAB );
1344 assert( n<=0 );
1345 if( p->db->mallocFailed ){
1346 freeP4(p->db, n, pP4);
1347 }else{
1348 assert( pP4!=0 );
1349 assert( p->nOp>0 );
1350 pOp = &p->aOp[p->nOp-1];
1351 assert( pOp->p4type==P4_NOTUSED );
1352 pOp->p4type = n;
1353 pOp->p4.p = pP4;
1354 }
1355 }
1356
1357 /*
1358 ** Set the P4 on the most recently added opcode to the KeyInfo for the
1359 ** index given.
1360 */
sqlite3VdbeSetP4KeyInfo(Parse * pParse,Index * pIdx)1361 void sqlite3VdbeSetP4KeyInfo(Parse *pParse, Index *pIdx){
1362 Vdbe *v = pParse->pVdbe;
1363 KeyInfo *pKeyInfo;
1364 assert( v!=0 );
1365 assert( pIdx!=0 );
1366 pKeyInfo = sqlite3KeyInfoOfIndex(pParse, pIdx);
1367 if( pKeyInfo ) sqlite3VdbeAppendP4(v, pKeyInfo, P4_KEYINFO);
1368 }
1369
1370 #ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
1371 /*
1372 ** Change the comment on the most recently coded instruction. Or
1373 ** insert a No-op and add the comment to that new instruction. This
1374 ** makes the code easier to read during debugging. None of this happens
1375 ** in a production build.
1376 */
vdbeVComment(Vdbe * p,const char * zFormat,va_list ap)1377 static void vdbeVComment(Vdbe *p, const char *zFormat, va_list ap){
1378 assert( p->nOp>0 || p->aOp==0 );
1379 assert( p->aOp==0 || p->aOp[p->nOp-1].zComment==0 || p->db->mallocFailed
1380 || p->pParse->nErr>0 );
1381 if( p->nOp ){
1382 assert( p->aOp );
1383 sqlite3DbFree(p->db, p->aOp[p->nOp-1].zComment);
1384 p->aOp[p->nOp-1].zComment = sqlite3VMPrintf(p->db, zFormat, ap);
1385 }
1386 }
sqlite3VdbeComment(Vdbe * p,const char * zFormat,...)1387 void sqlite3VdbeComment(Vdbe *p, const char *zFormat, ...){
1388 va_list ap;
1389 if( p ){
1390 va_start(ap, zFormat);
1391 vdbeVComment(p, zFormat, ap);
1392 va_end(ap);
1393 }
1394 }
sqlite3VdbeNoopComment(Vdbe * p,const char * zFormat,...)1395 void sqlite3VdbeNoopComment(Vdbe *p, const char *zFormat, ...){
1396 va_list ap;
1397 if( p ){
1398 sqlite3VdbeAddOp0(p, OP_Noop);
1399 va_start(ap, zFormat);
1400 vdbeVComment(p, zFormat, ap);
1401 va_end(ap);
1402 }
1403 }
1404 #endif /* NDEBUG */
1405
1406 #ifdef SQLITE_VDBE_COVERAGE
1407 /*
1408 ** Set the value if the iSrcLine field for the previously coded instruction.
1409 */
sqlite3VdbeSetLineNumber(Vdbe * v,int iLine)1410 void sqlite3VdbeSetLineNumber(Vdbe *v, int iLine){
1411 sqlite3VdbeGetOp(v,-1)->iSrcLine = iLine;
1412 }
1413 #endif /* SQLITE_VDBE_COVERAGE */
1414
1415 /*
1416 ** Return the opcode for a given address. If the address is -1, then
1417 ** return the most recently inserted opcode.
1418 **
1419 ** If a memory allocation error has occurred prior to the calling of this
1420 ** routine, then a pointer to a dummy VdbeOp will be returned. That opcode
1421 ** is readable but not writable, though it is cast to a writable value.
1422 ** The return of a dummy opcode allows the call to continue functioning
1423 ** after an OOM fault without having to check to see if the return from
1424 ** this routine is a valid pointer. But because the dummy.opcode is 0,
1425 ** dummy will never be written to. This is verified by code inspection and
1426 ** by running with Valgrind.
1427 */
sqlite3VdbeGetOp(Vdbe * p,int addr)1428 VdbeOp *sqlite3VdbeGetOp(Vdbe *p, int addr){
1429 /* C89 specifies that the constant "dummy" will be initialized to all
1430 ** zeros, which is correct. MSVC generates a warning, nevertheless. */
1431 static VdbeOp dummy; /* Ignore the MSVC warning about no initializer */
1432 assert( p->iVdbeMagic==VDBE_MAGIC_INIT );
1433 if( addr<0 ){
1434 addr = p->nOp - 1;
1435 }
1436 assert( (addr>=0 && addr<p->nOp) || p->db->mallocFailed );
1437 if( p->db->mallocFailed ){
1438 return (VdbeOp*)&dummy;
1439 }else{
1440 return &p->aOp[addr];
1441 }
1442 }
1443
1444 #if defined(SQLITE_ENABLE_EXPLAIN_COMMENTS)
1445 /*
1446 ** Return an integer value for one of the parameters to the opcode pOp
1447 ** determined by character c.
1448 */
translateP(char c,const Op * pOp)1449 static int translateP(char c, const Op *pOp){
1450 if( c=='1' ) return pOp->p1;
1451 if( c=='2' ) return pOp->p2;
1452 if( c=='3' ) return pOp->p3;
1453 if( c=='4' ) return pOp->p4.i;
1454 return pOp->p5;
1455 }
1456
1457 /*
1458 ** Compute a string for the "comment" field of a VDBE opcode listing.
1459 **
1460 ** The Synopsis: field in comments in the vdbe.c source file gets converted
1461 ** to an extra string that is appended to the sqlite3OpcodeName(). In the
1462 ** absence of other comments, this synopsis becomes the comment on the opcode.
1463 ** Some translation occurs:
1464 **
1465 ** "PX" -> "r[X]"
1466 ** "PX@PY" -> "r[X..X+Y-1]" or "r[x]" if y is 0 or 1
1467 ** "PX@PY+1" -> "r[X..X+Y]" or "r[x]" if y is 0
1468 ** "PY..PY" -> "r[X..Y]" or "r[x]" if y<=x
1469 */
sqlite3VdbeDisplayComment(sqlite3 * db,const Op * pOp,const char * zP4)1470 char *sqlite3VdbeDisplayComment(
1471 sqlite3 *db, /* Optional - Oom error reporting only */
1472 const Op *pOp, /* The opcode to be commented */
1473 const char *zP4 /* Previously obtained value for P4 */
1474 ){
1475 const char *zOpName;
1476 const char *zSynopsis;
1477 int nOpName;
1478 int ii;
1479 char zAlt[50];
1480 StrAccum x;
1481
1482 sqlite3StrAccumInit(&x, 0, 0, 0, SQLITE_MAX_LENGTH);
1483 zOpName = sqlite3OpcodeName(pOp->opcode);
1484 nOpName = sqlite3Strlen30(zOpName);
1485 if( zOpName[nOpName+1] ){
1486 int seenCom = 0;
1487 char c;
1488 zSynopsis = zOpName += nOpName + 1;
1489 if( strncmp(zSynopsis,"IF ",3)==0 ){
1490 if( pOp->p5 & SQLITE_STOREP2 ){
1491 sqlite3_snprintf(sizeof(zAlt), zAlt, "r[P2] = (%s)", zSynopsis+3);
1492 }else{
1493 sqlite3_snprintf(sizeof(zAlt), zAlt, "if %s goto P2", zSynopsis+3);
1494 }
1495 zSynopsis = zAlt;
1496 }
1497 for(ii=0; (c = zSynopsis[ii])!=0; ii++){
1498 if( c=='P' ){
1499 c = zSynopsis[++ii];
1500 if( c=='4' ){
1501 sqlite3_str_appendall(&x, zP4);
1502 }else if( c=='X' ){
1503 sqlite3_str_appendall(&x, pOp->zComment);
1504 seenCom = 1;
1505 }else{
1506 int v1 = translateP(c, pOp);
1507 int v2;
1508 if( strncmp(zSynopsis+ii+1, "@P", 2)==0 ){
1509 ii += 3;
1510 v2 = translateP(zSynopsis[ii], pOp);
1511 if( strncmp(zSynopsis+ii+1,"+1",2)==0 ){
1512 ii += 2;
1513 v2++;
1514 }
1515 if( v2<2 ){
1516 sqlite3_str_appendf(&x, "%d", v1);
1517 }else{
1518 sqlite3_str_appendf(&x, "%d..%d", v1, v1+v2-1);
1519 }
1520 }else if( strncmp(zSynopsis+ii+1, "@NP", 3)==0 ){
1521 sqlite3_context *pCtx = pOp->p4.pCtx;
1522 if( pOp->p4type!=P4_FUNCCTX || pCtx->argc==1 ){
1523 sqlite3_str_appendf(&x, "%d", v1);
1524 }else if( pCtx->argc>1 ){
1525 sqlite3_str_appendf(&x, "%d..%d", v1, v1+pCtx->argc-1);
1526 }else if( x.accError==0 ){
1527 assert( x.nChar>2 );
1528 x.nChar -= 2;
1529 ii++;
1530 }
1531 ii += 3;
1532 }else{
1533 sqlite3_str_appendf(&x, "%d", v1);
1534 if( strncmp(zSynopsis+ii+1, "..P3", 4)==0 && pOp->p3==0 ){
1535 ii += 4;
1536 }
1537 }
1538 }
1539 }else{
1540 sqlite3_str_appendchar(&x, 1, c);
1541 }
1542 }
1543 if( !seenCom && pOp->zComment ){
1544 sqlite3_str_appendf(&x, "; %s", pOp->zComment);
1545 }
1546 }else if( pOp->zComment ){
1547 sqlite3_str_appendall(&x, pOp->zComment);
1548 }
1549 if( (x.accError & SQLITE_NOMEM)!=0 && db!=0 ){
1550 sqlite3OomFault(db);
1551 }
1552 return sqlite3StrAccumFinish(&x);
1553 }
1554 #endif /* SQLITE_ENABLE_EXPLAIN_COMMENTS */
1555
1556 #if VDBE_DISPLAY_P4 && defined(SQLITE_ENABLE_CURSOR_HINTS)
1557 /*
1558 ** Translate the P4.pExpr value for an OP_CursorHint opcode into text
1559 ** that can be displayed in the P4 column of EXPLAIN output.
1560 */
displayP4Expr(StrAccum * p,Expr * pExpr)1561 static void displayP4Expr(StrAccum *p, Expr *pExpr){
1562 const char *zOp = 0;
1563 switch( pExpr->op ){
1564 case TK_STRING:
1565 sqlite3_str_appendf(p, "%Q", pExpr->u.zToken);
1566 break;
1567 case TK_INTEGER:
1568 sqlite3_str_appendf(p, "%d", pExpr->u.iValue);
1569 break;
1570 case TK_NULL:
1571 sqlite3_str_appendf(p, "NULL");
1572 break;
1573 case TK_REGISTER: {
1574 sqlite3_str_appendf(p, "r[%d]", pExpr->iTable);
1575 break;
1576 }
1577 case TK_COLUMN: {
1578 if( pExpr->iColumn<0 ){
1579 sqlite3_str_appendf(p, "rowid");
1580 }else{
1581 sqlite3_str_appendf(p, "c%d", (int)pExpr->iColumn);
1582 }
1583 break;
1584 }
1585 case TK_LT: zOp = "LT"; break;
1586 case TK_LE: zOp = "LE"; break;
1587 case TK_GT: zOp = "GT"; break;
1588 case TK_GE: zOp = "GE"; break;
1589 case TK_NE: zOp = "NE"; break;
1590 case TK_EQ: zOp = "EQ"; break;
1591 case TK_IS: zOp = "IS"; break;
1592 case TK_ISNOT: zOp = "ISNOT"; break;
1593 case TK_AND: zOp = "AND"; break;
1594 case TK_OR: zOp = "OR"; break;
1595 case TK_PLUS: zOp = "ADD"; break;
1596 case TK_STAR: zOp = "MUL"; break;
1597 case TK_MINUS: zOp = "SUB"; break;
1598 case TK_REM: zOp = "REM"; break;
1599 case TK_BITAND: zOp = "BITAND"; break;
1600 case TK_BITOR: zOp = "BITOR"; break;
1601 case TK_SLASH: zOp = "DIV"; break;
1602 case TK_LSHIFT: zOp = "LSHIFT"; break;
1603 case TK_RSHIFT: zOp = "RSHIFT"; break;
1604 case TK_CONCAT: zOp = "CONCAT"; break;
1605 case TK_UMINUS: zOp = "MINUS"; break;
1606 case TK_UPLUS: zOp = "PLUS"; break;
1607 case TK_BITNOT: zOp = "BITNOT"; break;
1608 case TK_NOT: zOp = "NOT"; break;
1609 case TK_ISNULL: zOp = "ISNULL"; break;
1610 case TK_NOTNULL: zOp = "NOTNULL"; break;
1611
1612 default:
1613 sqlite3_str_appendf(p, "%s", "expr");
1614 break;
1615 }
1616
1617 if( zOp ){
1618 sqlite3_str_appendf(p, "%s(", zOp);
1619 displayP4Expr(p, pExpr->pLeft);
1620 if( pExpr->pRight ){
1621 sqlite3_str_append(p, ",", 1);
1622 displayP4Expr(p, pExpr->pRight);
1623 }
1624 sqlite3_str_append(p, ")", 1);
1625 }
1626 }
1627 #endif /* VDBE_DISPLAY_P4 && defined(SQLITE_ENABLE_CURSOR_HINTS) */
1628
1629
1630 #if VDBE_DISPLAY_P4
1631 /*
1632 ** Compute a string that describes the P4 parameter for an opcode.
1633 ** Use zTemp for any required temporary buffer space.
1634 */
sqlite3VdbeDisplayP4(sqlite3 * db,Op * pOp)1635 char *sqlite3VdbeDisplayP4(sqlite3 *db, Op *pOp){
1636 char *zP4 = 0;
1637 StrAccum x;
1638
1639 sqlite3StrAccumInit(&x, 0, 0, 0, SQLITE_MAX_LENGTH);
1640 switch( pOp->p4type ){
1641 case P4_KEYINFO: {
1642 int j;
1643 KeyInfo *pKeyInfo = pOp->p4.pKeyInfo;
1644 assert( pKeyInfo->aSortFlags!=0 );
1645 sqlite3_str_appendf(&x, "k(%d", pKeyInfo->nKeyField);
1646 for(j=0; j<pKeyInfo->nKeyField; j++){
1647 CollSeq *pColl = pKeyInfo->aColl[j];
1648 const char *zColl = pColl ? pColl->zName : "";
1649 if( strcmp(zColl, "BINARY")==0 ) zColl = "B";
1650 sqlite3_str_appendf(&x, ",%s%s%s",
1651 (pKeyInfo->aSortFlags[j] & KEYINFO_ORDER_DESC) ? "-" : "",
1652 (pKeyInfo->aSortFlags[j] & KEYINFO_ORDER_BIGNULL)? "N." : "",
1653 zColl);
1654 }
1655 sqlite3_str_append(&x, ")", 1);
1656 break;
1657 }
1658 #ifdef SQLITE_ENABLE_CURSOR_HINTS
1659 case P4_EXPR: {
1660 displayP4Expr(&x, pOp->p4.pExpr);
1661 break;
1662 }
1663 #endif
1664 case P4_COLLSEQ: {
1665 static const char *const encnames[] = {"?", "8", "16LE", "16BE"};
1666 CollSeq *pColl = pOp->p4.pColl;
1667 assert( pColl->enc>=0 && pColl->enc<4 );
1668 sqlite3_str_appendf(&x, "%.18s-%s", pColl->zName,
1669 encnames[pColl->enc]);
1670 break;
1671 }
1672 case P4_FUNCDEF: {
1673 FuncDef *pDef = pOp->p4.pFunc;
1674 sqlite3_str_appendf(&x, "%s(%d)", pDef->zName, pDef->nArg);
1675 break;
1676 }
1677 case P4_FUNCCTX: {
1678 FuncDef *pDef = pOp->p4.pCtx->pFunc;
1679 sqlite3_str_appendf(&x, "%s(%d)", pDef->zName, pDef->nArg);
1680 break;
1681 }
1682 case P4_INT64: {
1683 sqlite3_str_appendf(&x, "%lld", *pOp->p4.pI64);
1684 break;
1685 }
1686 case P4_INT32: {
1687 sqlite3_str_appendf(&x, "%d", pOp->p4.i);
1688 break;
1689 }
1690 case P4_REAL: {
1691 sqlite3_str_appendf(&x, "%.16g", *pOp->p4.pReal);
1692 break;
1693 }
1694 case P4_MEM: {
1695 Mem *pMem = pOp->p4.pMem;
1696 if( pMem->flags & MEM_Str ){
1697 zP4 = pMem->z;
1698 }else if( pMem->flags & (MEM_Int|MEM_IntReal) ){
1699 sqlite3_str_appendf(&x, "%lld", pMem->u.i);
1700 }else if( pMem->flags & MEM_Real ){
1701 sqlite3_str_appendf(&x, "%.16g", pMem->u.r);
1702 }else if( pMem->flags & MEM_Null ){
1703 zP4 = "NULL";
1704 }else{
1705 assert( pMem->flags & MEM_Blob );
1706 zP4 = "(blob)";
1707 }
1708 break;
1709 }
1710 #ifndef SQLITE_OMIT_VIRTUALTABLE
1711 case P4_VTAB: {
1712 sqlite3_vtab *pVtab = pOp->p4.pVtab->pVtab;
1713 sqlite3_str_appendf(&x, "vtab:%p", pVtab);
1714 break;
1715 }
1716 #endif
1717 case P4_INTARRAY: {
1718 u32 i;
1719 u32 *ai = pOp->p4.ai;
1720 u32 n = ai[0]; /* The first element of an INTARRAY is always the
1721 ** count of the number of elements to follow */
1722 for(i=1; i<=n; i++){
1723 sqlite3_str_appendf(&x, "%c%u", (i==1 ? '[' : ','), ai[i]);
1724 }
1725 sqlite3_str_append(&x, "]", 1);
1726 break;
1727 }
1728 case P4_SUBPROGRAM: {
1729 zP4 = "program";
1730 break;
1731 }
1732 case P4_DYNBLOB:
1733 case P4_ADVANCE: {
1734 break;
1735 }
1736 case P4_TABLE: {
1737 zP4 = pOp->p4.pTab->zName;
1738 break;
1739 }
1740 default: {
1741 zP4 = pOp->p4.z;
1742 }
1743 }
1744 if( zP4 ) sqlite3_str_appendall(&x, zP4);
1745 if( (x.accError & SQLITE_NOMEM)!=0 ){
1746 sqlite3OomFault(db);
1747 }
1748 return sqlite3StrAccumFinish(&x);
1749 }
1750 #endif /* VDBE_DISPLAY_P4 */
1751
1752 /*
1753 ** Declare to the Vdbe that the BTree object at db->aDb[i] is used.
1754 **
1755 ** The prepared statements need to know in advance the complete set of
1756 ** attached databases that will be use. A mask of these databases
1757 ** is maintained in p->btreeMask. The p->lockMask value is the subset of
1758 ** p->btreeMask of databases that will require a lock.
1759 */
sqlite3VdbeUsesBtree(Vdbe * p,int i)1760 void sqlite3VdbeUsesBtree(Vdbe *p, int i){
1761 assert( i>=0 && i<p->db->nDb && i<(int)sizeof(yDbMask)*8 );
1762 assert( i<(int)sizeof(p->btreeMask)*8 );
1763 DbMaskSet(p->btreeMask, i);
1764 if( i!=1 && sqlite3BtreeSharable(p->db->aDb[i].pBt) ){
1765 DbMaskSet(p->lockMask, i);
1766 }
1767 }
1768
1769 #if !defined(SQLITE_OMIT_SHARED_CACHE)
1770 /*
1771 ** If SQLite is compiled to support shared-cache mode and to be threadsafe,
1772 ** this routine obtains the mutex associated with each BtShared structure
1773 ** that may be accessed by the VM passed as an argument. In doing so it also
1774 ** sets the BtShared.db member of each of the BtShared structures, ensuring
1775 ** that the correct busy-handler callback is invoked if required.
1776 **
1777 ** If SQLite is not threadsafe but does support shared-cache mode, then
1778 ** sqlite3BtreeEnter() is invoked to set the BtShared.db variables
1779 ** of all of BtShared structures accessible via the database handle
1780 ** associated with the VM.
1781 **
1782 ** If SQLite is not threadsafe and does not support shared-cache mode, this
1783 ** function is a no-op.
1784 **
1785 ** The p->btreeMask field is a bitmask of all btrees that the prepared
1786 ** statement p will ever use. Let N be the number of bits in p->btreeMask
1787 ** corresponding to btrees that use shared cache. Then the runtime of
1788 ** this routine is N*N. But as N is rarely more than 1, this should not
1789 ** be a problem.
1790 */
sqlite3VdbeEnter(Vdbe * p)1791 void sqlite3VdbeEnter(Vdbe *p){
1792 int i;
1793 sqlite3 *db;
1794 Db *aDb;
1795 int nDb;
1796 if( DbMaskAllZero(p->lockMask) ) return; /* The common case */
1797 db = p->db;
1798 aDb = db->aDb;
1799 nDb = db->nDb;
1800 for(i=0; i<nDb; i++){
1801 if( i!=1 && DbMaskTest(p->lockMask,i) && ALWAYS(aDb[i].pBt!=0) ){
1802 sqlite3BtreeEnter(aDb[i].pBt);
1803 }
1804 }
1805 }
1806 #endif
1807
1808 #if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
1809 /*
1810 ** Unlock all of the btrees previously locked by a call to sqlite3VdbeEnter().
1811 */
vdbeLeave(Vdbe * p)1812 static SQLITE_NOINLINE void vdbeLeave(Vdbe *p){
1813 int i;
1814 sqlite3 *db;
1815 Db *aDb;
1816 int nDb;
1817 db = p->db;
1818 aDb = db->aDb;
1819 nDb = db->nDb;
1820 for(i=0; i<nDb; i++){
1821 if( i!=1 && DbMaskTest(p->lockMask,i) && ALWAYS(aDb[i].pBt!=0) ){
1822 sqlite3BtreeLeave(aDb[i].pBt);
1823 }
1824 }
1825 }
sqlite3VdbeLeave(Vdbe * p)1826 void sqlite3VdbeLeave(Vdbe *p){
1827 if( DbMaskAllZero(p->lockMask) ) return; /* The common case */
1828 vdbeLeave(p);
1829 }
1830 #endif
1831
1832 #if defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
1833 /*
1834 ** Print a single opcode. This routine is used for debugging only.
1835 */
sqlite3VdbePrintOp(FILE * pOut,int pc,VdbeOp * pOp)1836 void sqlite3VdbePrintOp(FILE *pOut, int pc, VdbeOp *pOp){
1837 char *zP4;
1838 char *zCom;
1839 sqlite3 dummyDb;
1840 static const char *zFormat1 = "%4d %-13s %4d %4d %4d %-13s %.2X %s\n";
1841 if( pOut==0 ) pOut = stdout;
1842 sqlite3BeginBenignMalloc();
1843 dummyDb.mallocFailed = 1;
1844 zP4 = sqlite3VdbeDisplayP4(&dummyDb, pOp);
1845 #ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
1846 zCom = sqlite3VdbeDisplayComment(0, pOp, zP4);
1847 #else
1848 zCom = 0;
1849 #endif
1850 /* NB: The sqlite3OpcodeName() function is implemented by code created
1851 ** by the mkopcodeh.awk and mkopcodec.awk scripts which extract the
1852 ** information from the vdbe.c source text */
1853 fprintf(pOut, zFormat1, pc,
1854 sqlite3OpcodeName(pOp->opcode), pOp->p1, pOp->p2, pOp->p3,
1855 zP4 ? zP4 : "", pOp->p5,
1856 zCom ? zCom : ""
1857 );
1858 fflush(pOut);
1859 sqlite3_free(zP4);
1860 sqlite3_free(zCom);
1861 sqlite3EndBenignMalloc();
1862 }
1863 #endif
1864
1865 /*
1866 ** Initialize an array of N Mem element.
1867 */
initMemArray(Mem * p,int N,sqlite3 * db,u16 flags)1868 static void initMemArray(Mem *p, int N, sqlite3 *db, u16 flags){
1869 while( (N--)>0 ){
1870 p->db = db;
1871 p->flags = flags;
1872 p->szMalloc = 0;
1873 #ifdef SQLITE_DEBUG
1874 p->pScopyFrom = 0;
1875 #endif
1876 p++;
1877 }
1878 }
1879
1880 /*
1881 ** Release an array of N Mem elements
1882 */
releaseMemArray(Mem * p,int N)1883 static void releaseMemArray(Mem *p, int N){
1884 if( p && N ){
1885 Mem *pEnd = &p[N];
1886 sqlite3 *db = p->db;
1887 if( db->pnBytesFreed ){
1888 do{
1889 if( p->szMalloc ) sqlite3DbFree(db, p->zMalloc);
1890 }while( (++p)<pEnd );
1891 return;
1892 }
1893 do{
1894 assert( (&p[1])==pEnd || p[0].db==p[1].db );
1895 assert( sqlite3VdbeCheckMemInvariants(p) );
1896
1897 /* This block is really an inlined version of sqlite3VdbeMemRelease()
1898 ** that takes advantage of the fact that the memory cell value is
1899 ** being set to NULL after releasing any dynamic resources.
1900 **
1901 ** The justification for duplicating code is that according to
1902 ** callgrind, this causes a certain test case to hit the CPU 4.7
1903 ** percent less (x86 linux, gcc version 4.1.2, -O6) than if
1904 ** sqlite3MemRelease() were called from here. With -O2, this jumps
1905 ** to 6.6 percent. The test case is inserting 1000 rows into a table
1906 ** with no indexes using a single prepared INSERT statement, bind()
1907 ** and reset(). Inserts are grouped into a transaction.
1908 */
1909 testcase( p->flags & MEM_Agg );
1910 testcase( p->flags & MEM_Dyn );
1911 testcase( p->xDel==sqlite3VdbeFrameMemDel );
1912 if( p->flags&(MEM_Agg|MEM_Dyn) ){
1913 sqlite3VdbeMemRelease(p);
1914 }else if( p->szMalloc ){
1915 sqlite3DbFreeNN(db, p->zMalloc);
1916 p->szMalloc = 0;
1917 }
1918
1919 p->flags = MEM_Undefined;
1920 }while( (++p)<pEnd );
1921 }
1922 }
1923
1924 #ifdef SQLITE_DEBUG
1925 /*
1926 ** Verify that pFrame is a valid VdbeFrame pointer. Return true if it is
1927 ** and false if something is wrong.
1928 **
1929 ** This routine is intended for use inside of assert() statements only.
1930 */
sqlite3VdbeFrameIsValid(VdbeFrame * pFrame)1931 int sqlite3VdbeFrameIsValid(VdbeFrame *pFrame){
1932 if( pFrame->iFrameMagic!=SQLITE_FRAME_MAGIC ) return 0;
1933 return 1;
1934 }
1935 #endif
1936
1937
1938 /*
1939 ** This is a destructor on a Mem object (which is really an sqlite3_value)
1940 ** that deletes the Frame object that is attached to it as a blob.
1941 **
1942 ** This routine does not delete the Frame right away. It merely adds the
1943 ** frame to a list of frames to be deleted when the Vdbe halts.
1944 */
sqlite3VdbeFrameMemDel(void * pArg)1945 void sqlite3VdbeFrameMemDel(void *pArg){
1946 VdbeFrame *pFrame = (VdbeFrame*)pArg;
1947 assert( sqlite3VdbeFrameIsValid(pFrame) );
1948 pFrame->pParent = pFrame->v->pDelFrame;
1949 pFrame->v->pDelFrame = pFrame;
1950 }
1951
1952 #if defined(SQLITE_ENABLE_BYTECODE_VTAB) || !defined(SQLITE_OMIT_EXPLAIN)
1953 /*
1954 ** Locate the next opcode to be displayed in EXPLAIN or EXPLAIN
1955 ** QUERY PLAN output.
1956 **
1957 ** Return SQLITE_ROW on success. Return SQLITE_DONE if there are no
1958 ** more opcodes to be displayed.
1959 */
sqlite3VdbeNextOpcode(Vdbe * p,Mem * pSub,int eMode,int * piPc,int * piAddr,Op ** paOp)1960 int sqlite3VdbeNextOpcode(
1961 Vdbe *p, /* The statement being explained */
1962 Mem *pSub, /* Storage for keeping track of subprogram nesting */
1963 int eMode, /* 0: normal. 1: EQP. 2: TablesUsed */
1964 int *piPc, /* IN/OUT: Current rowid. Overwritten with next rowid */
1965 int *piAddr, /* OUT: Write index into (*paOp)[] here */
1966 Op **paOp /* OUT: Write the opcode array here */
1967 ){
1968 int nRow; /* Stop when row count reaches this */
1969 int nSub = 0; /* Number of sub-vdbes seen so far */
1970 SubProgram **apSub = 0; /* Array of sub-vdbes */
1971 int i; /* Next instruction address */
1972 int rc = SQLITE_OK; /* Result code */
1973 Op *aOp = 0; /* Opcode array */
1974 int iPc; /* Rowid. Copy of value in *piPc */
1975
1976 /* When the number of output rows reaches nRow, that means the
1977 ** listing has finished and sqlite3_step() should return SQLITE_DONE.
1978 ** nRow is the sum of the number of rows in the main program, plus
1979 ** the sum of the number of rows in all trigger subprograms encountered
1980 ** so far. The nRow value will increase as new trigger subprograms are
1981 ** encountered, but p->pc will eventually catch up to nRow.
1982 */
1983 nRow = p->nOp;
1984 if( pSub!=0 ){
1985 if( pSub->flags&MEM_Blob ){
1986 /* pSub is initiallly NULL. It is initialized to a BLOB by
1987 ** the P4_SUBPROGRAM processing logic below */
1988 nSub = pSub->n/sizeof(Vdbe*);
1989 apSub = (SubProgram **)pSub->z;
1990 }
1991 for(i=0; i<nSub; i++){
1992 nRow += apSub[i]->nOp;
1993 }
1994 }
1995 iPc = *piPc;
1996 while(1){ /* Loop exits via break */
1997 i = iPc++;
1998 if( i>=nRow ){
1999 p->rc = SQLITE_OK;
2000 rc = SQLITE_DONE;
2001 break;
2002 }
2003 if( i<p->nOp ){
2004 /* The rowid is small enough that we are still in the
2005 ** main program. */
2006 aOp = p->aOp;
2007 }else{
2008 /* We are currently listing subprograms. Figure out which one and
2009 ** pick up the appropriate opcode. */
2010 int j;
2011 i -= p->nOp;
2012 assert( apSub!=0 );
2013 assert( nSub>0 );
2014 for(j=0; i>=apSub[j]->nOp; j++){
2015 i -= apSub[j]->nOp;
2016 assert( i<apSub[j]->nOp || j+1<nSub );
2017 }
2018 aOp = apSub[j]->aOp;
2019 }
2020
2021 /* When an OP_Program opcode is encounter (the only opcode that has
2022 ** a P4_SUBPROGRAM argument), expand the size of the array of subprograms
2023 ** kept in p->aMem[9].z to hold the new program - assuming this subprogram
2024 ** has not already been seen.
2025 */
2026 if( pSub!=0 && aOp[i].p4type==P4_SUBPROGRAM ){
2027 int nByte = (nSub+1)*sizeof(SubProgram*);
2028 int j;
2029 for(j=0; j<nSub; j++){
2030 if( apSub[j]==aOp[i].p4.pProgram ) break;
2031 }
2032 if( j==nSub ){
2033 p->rc = sqlite3VdbeMemGrow(pSub, nByte, nSub!=0);
2034 if( p->rc!=SQLITE_OK ){
2035 rc = SQLITE_ERROR;
2036 break;
2037 }
2038 apSub = (SubProgram **)pSub->z;
2039 apSub[nSub++] = aOp[i].p4.pProgram;
2040 MemSetTypeFlag(pSub, MEM_Blob);
2041 pSub->n = nSub*sizeof(SubProgram*);
2042 nRow += aOp[i].p4.pProgram->nOp;
2043 }
2044 }
2045 if( eMode==0 ) break;
2046 #ifdef SQLITE_ENABLE_BYTECODE_VTAB
2047 if( eMode==2 ){
2048 Op *pOp = aOp + i;
2049 if( pOp->opcode==OP_OpenRead ) break;
2050 if( pOp->opcode==OP_OpenWrite && (pOp->p5 & OPFLAG_P2ISREG)==0 ) break;
2051 if( pOp->opcode==OP_ReopenIdx ) break;
2052 }else
2053 #endif
2054 {
2055 assert( eMode==1 );
2056 if( aOp[i].opcode==OP_Explain ) break;
2057 if( aOp[i].opcode==OP_Init && iPc>1 ) break;
2058 }
2059 }
2060 *piPc = iPc;
2061 *piAddr = i;
2062 *paOp = aOp;
2063 return rc;
2064 }
2065 #endif /* SQLITE_ENABLE_BYTECODE_VTAB || !SQLITE_OMIT_EXPLAIN */
2066
2067
2068 /*
2069 ** Delete a VdbeFrame object and its contents. VdbeFrame objects are
2070 ** allocated by the OP_Program opcode in sqlite3VdbeExec().
2071 */
sqlite3VdbeFrameDelete(VdbeFrame * p)2072 void sqlite3VdbeFrameDelete(VdbeFrame *p){
2073 int i;
2074 Mem *aMem = VdbeFrameMem(p);
2075 VdbeCursor **apCsr = (VdbeCursor **)&aMem[p->nChildMem];
2076 assert( sqlite3VdbeFrameIsValid(p) );
2077 for(i=0; i<p->nChildCsr; i++){
2078 sqlite3VdbeFreeCursor(p->v, apCsr[i]);
2079 }
2080 releaseMemArray(aMem, p->nChildMem);
2081 sqlite3VdbeDeleteAuxData(p->v->db, &p->pAuxData, -1, 0);
2082 sqlite3DbFree(p->v->db, p);
2083 }
2084
2085 #ifndef SQLITE_OMIT_EXPLAIN
2086 /*
2087 ** Give a listing of the program in the virtual machine.
2088 **
2089 ** The interface is the same as sqlite3VdbeExec(). But instead of
2090 ** running the code, it invokes the callback once for each instruction.
2091 ** This feature is used to implement "EXPLAIN".
2092 **
2093 ** When p->explain==1, each instruction is listed. When
2094 ** p->explain==2, only OP_Explain instructions are listed and these
2095 ** are shown in a different format. p->explain==2 is used to implement
2096 ** EXPLAIN QUERY PLAN.
2097 ** 2018-04-24: In p->explain==2 mode, the OP_Init opcodes of triggers
2098 ** are also shown, so that the boundaries between the main program and
2099 ** each trigger are clear.
2100 **
2101 ** When p->explain==1, first the main program is listed, then each of
2102 ** the trigger subprograms are listed one by one.
2103 */
sqlite3VdbeList(Vdbe * p)2104 int sqlite3VdbeList(
2105 Vdbe *p /* The VDBE */
2106 ){
2107 Mem *pSub = 0; /* Memory cell hold array of subprogs */
2108 sqlite3 *db = p->db; /* The database connection */
2109 int i; /* Loop counter */
2110 int rc = SQLITE_OK; /* Return code */
2111 Mem *pMem = &p->aMem[1]; /* First Mem of result set */
2112 int bListSubprogs = (p->explain==1 || (db->flags & SQLITE_TriggerEQP)!=0);
2113 Op *aOp; /* Array of opcodes */
2114 Op *pOp; /* Current opcode */
2115
2116 assert( p->explain );
2117 assert( p->iVdbeMagic==VDBE_MAGIC_RUN );
2118 assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY || p->rc==SQLITE_NOMEM );
2119
2120 /* Even though this opcode does not use dynamic strings for
2121 ** the result, result columns may become dynamic if the user calls
2122 ** sqlite3_column_text16(), causing a translation to UTF-16 encoding.
2123 */
2124 releaseMemArray(pMem, 8);
2125 p->pResultSet = 0;
2126
2127 if( p->rc==SQLITE_NOMEM ){
2128 /* This happens if a malloc() inside a call to sqlite3_column_text() or
2129 ** sqlite3_column_text16() failed. */
2130 sqlite3OomFault(db);
2131 return SQLITE_ERROR;
2132 }
2133
2134 if( bListSubprogs ){
2135 /* The first 8 memory cells are used for the result set. So we will
2136 ** commandeer the 9th cell to use as storage for an array of pointers
2137 ** to trigger subprograms. The VDBE is guaranteed to have at least 9
2138 ** cells. */
2139 assert( p->nMem>9 );
2140 pSub = &p->aMem[9];
2141 }else{
2142 pSub = 0;
2143 }
2144
2145 /* Figure out which opcode is next to display */
2146 rc = sqlite3VdbeNextOpcode(p, pSub, p->explain==2, &p->pc, &i, &aOp);
2147
2148 if( rc==SQLITE_OK ){
2149 pOp = aOp + i;
2150 if( AtomicLoad(&db->u1.isInterrupted) ){
2151 p->rc = SQLITE_INTERRUPT;
2152 rc = SQLITE_ERROR;
2153 sqlite3VdbeError(p, sqlite3ErrStr(p->rc));
2154 }else{
2155 char *zP4 = sqlite3VdbeDisplayP4(db, pOp);
2156 if( p->explain==2 ){
2157 sqlite3VdbeMemSetInt64(pMem, pOp->p1);
2158 sqlite3VdbeMemSetInt64(pMem+1, pOp->p2);
2159 sqlite3VdbeMemSetInt64(pMem+2, pOp->p3);
2160 sqlite3VdbeMemSetStr(pMem+3, zP4, -1, SQLITE_UTF8, sqlite3_free);
2161 p->nResColumn = 4;
2162 }else{
2163 sqlite3VdbeMemSetInt64(pMem+0, i);
2164 sqlite3VdbeMemSetStr(pMem+1, (char*)sqlite3OpcodeName(pOp->opcode),
2165 -1, SQLITE_UTF8, SQLITE_STATIC);
2166 sqlite3VdbeMemSetInt64(pMem+2, pOp->p1);
2167 sqlite3VdbeMemSetInt64(pMem+3, pOp->p2);
2168 sqlite3VdbeMemSetInt64(pMem+4, pOp->p3);
2169 /* pMem+5 for p4 is done last */
2170 sqlite3VdbeMemSetInt64(pMem+6, pOp->p5);
2171 #ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
2172 {
2173 char *zCom = sqlite3VdbeDisplayComment(db, pOp, zP4);
2174 sqlite3VdbeMemSetStr(pMem+7, zCom, -1, SQLITE_UTF8, sqlite3_free);
2175 }
2176 #else
2177 sqlite3VdbeMemSetNull(pMem+7);
2178 #endif
2179 sqlite3VdbeMemSetStr(pMem+5, zP4, -1, SQLITE_UTF8, sqlite3_free);
2180 p->nResColumn = 8;
2181 }
2182 p->pResultSet = pMem;
2183 if( db->mallocFailed ){
2184 p->rc = SQLITE_NOMEM;
2185 rc = SQLITE_ERROR;
2186 }else{
2187 p->rc = SQLITE_OK;
2188 rc = SQLITE_ROW;
2189 }
2190 }
2191 }
2192 return rc;
2193 }
2194 #endif /* SQLITE_OMIT_EXPLAIN */
2195
2196 #ifdef SQLITE_DEBUG
2197 /*
2198 ** Print the SQL that was used to generate a VDBE program.
2199 */
sqlite3VdbePrintSql(Vdbe * p)2200 void sqlite3VdbePrintSql(Vdbe *p){
2201 const char *z = 0;
2202 if( p->zSql ){
2203 z = p->zSql;
2204 }else if( p->nOp>=1 ){
2205 const VdbeOp *pOp = &p->aOp[0];
2206 if( pOp->opcode==OP_Init && pOp->p4.z!=0 ){
2207 z = pOp->p4.z;
2208 while( sqlite3Isspace(*z) ) z++;
2209 }
2210 }
2211 if( z ) printf("SQL: [%s]\n", z);
2212 }
2213 #endif
2214
2215 #if !defined(SQLITE_OMIT_TRACE) && defined(SQLITE_ENABLE_IOTRACE)
2216 /*
2217 ** Print an IOTRACE message showing SQL content.
2218 */
sqlite3VdbeIOTraceSql(Vdbe * p)2219 void sqlite3VdbeIOTraceSql(Vdbe *p){
2220 int nOp = p->nOp;
2221 VdbeOp *pOp;
2222 if( sqlite3IoTrace==0 ) return;
2223 if( nOp<1 ) return;
2224 pOp = &p->aOp[0];
2225 if( pOp->opcode==OP_Init && pOp->p4.z!=0 ){
2226 int i, j;
2227 char z[1000];
2228 sqlite3_snprintf(sizeof(z), z, "%s", pOp->p4.z);
2229 for(i=0; sqlite3Isspace(z[i]); i++){}
2230 for(j=0; z[i]; i++){
2231 if( sqlite3Isspace(z[i]) ){
2232 if( z[i-1]!=' ' ){
2233 z[j++] = ' ';
2234 }
2235 }else{
2236 z[j++] = z[i];
2237 }
2238 }
2239 z[j] = 0;
2240 sqlite3IoTrace("SQL %s\n", z);
2241 }
2242 }
2243 #endif /* !SQLITE_OMIT_TRACE && SQLITE_ENABLE_IOTRACE */
2244
2245 /* An instance of this object describes bulk memory available for use
2246 ** by subcomponents of a prepared statement. Space is allocated out
2247 ** of a ReusableSpace object by the allocSpace() routine below.
2248 */
2249 struct ReusableSpace {
2250 u8 *pSpace; /* Available memory */
2251 sqlite3_int64 nFree; /* Bytes of available memory */
2252 sqlite3_int64 nNeeded; /* Total bytes that could not be allocated */
2253 };
2254
2255 /* Try to allocate nByte bytes of 8-byte aligned bulk memory for pBuf
2256 ** from the ReusableSpace object. Return a pointer to the allocated
2257 ** memory on success. If insufficient memory is available in the
2258 ** ReusableSpace object, increase the ReusableSpace.nNeeded
2259 ** value by the amount needed and return NULL.
2260 **
2261 ** If pBuf is not initially NULL, that means that the memory has already
2262 ** been allocated by a prior call to this routine, so just return a copy
2263 ** of pBuf and leave ReusableSpace unchanged.
2264 **
2265 ** This allocator is employed to repurpose unused slots at the end of the
2266 ** opcode array of prepared state for other memory needs of the prepared
2267 ** statement.
2268 */
allocSpace(struct ReusableSpace * p,void * pBuf,sqlite3_int64 nByte)2269 static void *allocSpace(
2270 struct ReusableSpace *p, /* Bulk memory available for allocation */
2271 void *pBuf, /* Pointer to a prior allocation */
2272 sqlite3_int64 nByte /* Bytes of memory needed */
2273 ){
2274 assert( EIGHT_BYTE_ALIGNMENT(p->pSpace) );
2275 if( pBuf==0 ){
2276 nByte = ROUND8(nByte);
2277 if( nByte <= p->nFree ){
2278 p->nFree -= nByte;
2279 pBuf = &p->pSpace[p->nFree];
2280 }else{
2281 p->nNeeded += nByte;
2282 }
2283 }
2284 assert( EIGHT_BYTE_ALIGNMENT(pBuf) );
2285 return pBuf;
2286 }
2287
2288 /*
2289 ** Rewind the VDBE back to the beginning in preparation for
2290 ** running it.
2291 */
sqlite3VdbeRewind(Vdbe * p)2292 void sqlite3VdbeRewind(Vdbe *p){
2293 #if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
2294 int i;
2295 #endif
2296 assert( p!=0 );
2297 assert( p->iVdbeMagic==VDBE_MAGIC_INIT || p->iVdbeMagic==VDBE_MAGIC_RESET );
2298
2299 /* There should be at least one opcode.
2300 */
2301 assert( p->nOp>0 );
2302
2303 /* Set the magic to VDBE_MAGIC_RUN sooner rather than later. */
2304 p->iVdbeMagic = VDBE_MAGIC_RUN;
2305
2306 #ifdef SQLITE_DEBUG
2307 for(i=0; i<p->nMem; i++){
2308 assert( p->aMem[i].db==p->db );
2309 }
2310 #endif
2311 p->pc = -1;
2312 p->rc = SQLITE_OK;
2313 p->errorAction = OE_Abort;
2314 p->nChange = 0;
2315 p->cacheCtr = 1;
2316 p->minWriteFileFormat = 255;
2317 p->iStatement = 0;
2318 p->nFkConstraint = 0;
2319 #ifdef VDBE_PROFILE
2320 for(i=0; i<p->nOp; i++){
2321 p->aOp[i].cnt = 0;
2322 p->aOp[i].cycles = 0;
2323 }
2324 #endif
2325 }
2326
2327 /*
2328 ** Prepare a virtual machine for execution for the first time after
2329 ** creating the virtual machine. This involves things such
2330 ** as allocating registers and initializing the program counter.
2331 ** After the VDBE has be prepped, it can be executed by one or more
2332 ** calls to sqlite3VdbeExec().
2333 **
2334 ** This function may be called exactly once on each virtual machine.
2335 ** After this routine is called the VM has been "packaged" and is ready
2336 ** to run. After this routine is called, further calls to
2337 ** sqlite3VdbeAddOp() functions are prohibited. This routine disconnects
2338 ** the Vdbe from the Parse object that helped generate it so that the
2339 ** the Vdbe becomes an independent entity and the Parse object can be
2340 ** destroyed.
2341 **
2342 ** Use the sqlite3VdbeRewind() procedure to restore a virtual machine back
2343 ** to its initial state after it has been run.
2344 */
sqlite3VdbeMakeReady(Vdbe * p,Parse * pParse)2345 void sqlite3VdbeMakeReady(
2346 Vdbe *p, /* The VDBE */
2347 Parse *pParse /* Parsing context */
2348 ){
2349 sqlite3 *db; /* The database connection */
2350 int nVar; /* Number of parameters */
2351 int nMem; /* Number of VM memory registers */
2352 int nCursor; /* Number of cursors required */
2353 int nArg; /* Number of arguments in subprograms */
2354 int n; /* Loop counter */
2355 struct ReusableSpace x; /* Reusable bulk memory */
2356
2357 assert( p!=0 );
2358 assert( p->nOp>0 );
2359 assert( pParse!=0 );
2360 assert( p->iVdbeMagic==VDBE_MAGIC_INIT );
2361 assert( pParse==p->pParse );
2362 p->pVList = pParse->pVList;
2363 pParse->pVList = 0;
2364 db = p->db;
2365 assert( db->mallocFailed==0 );
2366 nVar = pParse->nVar;
2367 nMem = pParse->nMem;
2368 nCursor = pParse->nTab;
2369 nArg = pParse->nMaxArg;
2370
2371 /* Each cursor uses a memory cell. The first cursor (cursor 0) can
2372 ** use aMem[0] which is not otherwise used by the VDBE program. Allocate
2373 ** space at the end of aMem[] for cursors 1 and greater.
2374 ** See also: allocateCursor().
2375 */
2376 nMem += nCursor;
2377 if( nCursor==0 && nMem>0 ) nMem++; /* Space for aMem[0] even if not used */
2378
2379 /* Figure out how much reusable memory is available at the end of the
2380 ** opcode array. This extra memory will be reallocated for other elements
2381 ** of the prepared statement.
2382 */
2383 n = ROUND8(sizeof(Op)*p->nOp); /* Bytes of opcode memory used */
2384 x.pSpace = &((u8*)p->aOp)[n]; /* Unused opcode memory */
2385 assert( EIGHT_BYTE_ALIGNMENT(x.pSpace) );
2386 x.nFree = ROUNDDOWN8(pParse->szOpAlloc - n); /* Bytes of unused memory */
2387 assert( x.nFree>=0 );
2388 assert( EIGHT_BYTE_ALIGNMENT(&x.pSpace[x.nFree]) );
2389
2390 resolveP2Values(p, &nArg);
2391 p->usesStmtJournal = (u8)(pParse->isMultiWrite && pParse->mayAbort);
2392 if( pParse->explain ){
2393 static const char * const azColName[] = {
2394 "addr", "opcode", "p1", "p2", "p3", "p4", "p5", "comment",
2395 "id", "parent", "notused", "detail"
2396 };
2397 int iFirst, mx, i;
2398 if( nMem<10 ) nMem = 10;
2399 p->explain = pParse->explain;
2400 if( pParse->explain==2 ){
2401 sqlite3VdbeSetNumCols(p, 4);
2402 iFirst = 8;
2403 mx = 12;
2404 }else{
2405 sqlite3VdbeSetNumCols(p, 8);
2406 iFirst = 0;
2407 mx = 8;
2408 }
2409 for(i=iFirst; i<mx; i++){
2410 sqlite3VdbeSetColName(p, i-iFirst, COLNAME_NAME,
2411 azColName[i], SQLITE_STATIC);
2412 }
2413 }
2414 p->expired = 0;
2415
2416 /* Memory for registers, parameters, cursor, etc, is allocated in one or two
2417 ** passes. On the first pass, we try to reuse unused memory at the
2418 ** end of the opcode array. If we are unable to satisfy all memory
2419 ** requirements by reusing the opcode array tail, then the second
2420 ** pass will fill in the remainder using a fresh memory allocation.
2421 **
2422 ** This two-pass approach that reuses as much memory as possible from
2423 ** the leftover memory at the end of the opcode array. This can significantly
2424 ** reduce the amount of memory held by a prepared statement.
2425 */
2426 x.nNeeded = 0;
2427 p->aMem = allocSpace(&x, 0, nMem*sizeof(Mem));
2428 p->aVar = allocSpace(&x, 0, nVar*sizeof(Mem));
2429 p->apArg = allocSpace(&x, 0, nArg*sizeof(Mem*));
2430 p->apCsr = allocSpace(&x, 0, nCursor*sizeof(VdbeCursor*));
2431 #ifdef SQLITE_ENABLE_STMT_SCANSTATUS
2432 p->anExec = allocSpace(&x, 0, p->nOp*sizeof(i64));
2433 #endif
2434 if( x.nNeeded ){
2435 x.pSpace = p->pFree = sqlite3DbMallocRawNN(db, x.nNeeded);
2436 x.nFree = x.nNeeded;
2437 if( !db->mallocFailed ){
2438 p->aMem = allocSpace(&x, p->aMem, nMem*sizeof(Mem));
2439 p->aVar = allocSpace(&x, p->aVar, nVar*sizeof(Mem));
2440 p->apArg = allocSpace(&x, p->apArg, nArg*sizeof(Mem*));
2441 p->apCsr = allocSpace(&x, p->apCsr, nCursor*sizeof(VdbeCursor*));
2442 #ifdef SQLITE_ENABLE_STMT_SCANSTATUS
2443 p->anExec = allocSpace(&x, p->anExec, p->nOp*sizeof(i64));
2444 #endif
2445 }
2446 }
2447
2448 if( db->mallocFailed ){
2449 p->nVar = 0;
2450 p->nCursor = 0;
2451 p->nMem = 0;
2452 }else{
2453 p->nCursor = nCursor;
2454 p->nVar = (ynVar)nVar;
2455 initMemArray(p->aVar, nVar, db, MEM_Null);
2456 p->nMem = nMem;
2457 initMemArray(p->aMem, nMem, db, MEM_Undefined);
2458 memset(p->apCsr, 0, nCursor*sizeof(VdbeCursor*));
2459 #ifdef SQLITE_ENABLE_STMT_SCANSTATUS
2460 memset(p->anExec, 0, p->nOp*sizeof(i64));
2461 #endif
2462 }
2463 sqlite3VdbeRewind(p);
2464 }
2465
2466 /*
2467 ** Close a VDBE cursor and release all the resources that cursor
2468 ** happens to hold.
2469 */
sqlite3VdbeFreeCursor(Vdbe * p,VdbeCursor * pCx)2470 void sqlite3VdbeFreeCursor(Vdbe *p, VdbeCursor *pCx){
2471 if( pCx==0 ){
2472 return;
2473 }
2474 assert( pCx->pBtx==0 || pCx->eCurType==CURTYPE_BTREE );
2475 assert( pCx->pBtx==0 || pCx->isEphemeral );
2476 switch( pCx->eCurType ){
2477 case CURTYPE_SORTER: {
2478 sqlite3VdbeSorterClose(p->db, pCx);
2479 break;
2480 }
2481 case CURTYPE_BTREE: {
2482 assert( pCx->uc.pCursor!=0 );
2483 sqlite3BtreeCloseCursor(pCx->uc.pCursor);
2484 break;
2485 }
2486 #ifndef SQLITE_OMIT_VIRTUALTABLE
2487 case CURTYPE_VTAB: {
2488 sqlite3_vtab_cursor *pVCur = pCx->uc.pVCur;
2489 const sqlite3_module *pModule = pVCur->pVtab->pModule;
2490 assert( pVCur->pVtab->nRef>0 );
2491 pVCur->pVtab->nRef--;
2492 pModule->xClose(pVCur);
2493 break;
2494 }
2495 #endif
2496 }
2497 }
2498
2499 /*
2500 ** Close all cursors in the current frame.
2501 */
closeCursorsInFrame(Vdbe * p)2502 static void closeCursorsInFrame(Vdbe *p){
2503 if( p->apCsr ){
2504 int i;
2505 for(i=0; i<p->nCursor; i++){
2506 VdbeCursor *pC = p->apCsr[i];
2507 if( pC ){
2508 sqlite3VdbeFreeCursor(p, pC);
2509 p->apCsr[i] = 0;
2510 }
2511 }
2512 }
2513 }
2514
2515 /*
2516 ** Copy the values stored in the VdbeFrame structure to its Vdbe. This
2517 ** is used, for example, when a trigger sub-program is halted to restore
2518 ** control to the main program.
2519 */
sqlite3VdbeFrameRestore(VdbeFrame * pFrame)2520 int sqlite3VdbeFrameRestore(VdbeFrame *pFrame){
2521 Vdbe *v = pFrame->v;
2522 closeCursorsInFrame(v);
2523 #ifdef SQLITE_ENABLE_STMT_SCANSTATUS
2524 v->anExec = pFrame->anExec;
2525 #endif
2526 v->aOp = pFrame->aOp;
2527 v->nOp = pFrame->nOp;
2528 v->aMem = pFrame->aMem;
2529 v->nMem = pFrame->nMem;
2530 v->apCsr = pFrame->apCsr;
2531 v->nCursor = pFrame->nCursor;
2532 v->db->lastRowid = pFrame->lastRowid;
2533 v->nChange = pFrame->nChange;
2534 v->db->nChange = pFrame->nDbChange;
2535 sqlite3VdbeDeleteAuxData(v->db, &v->pAuxData, -1, 0);
2536 v->pAuxData = pFrame->pAuxData;
2537 pFrame->pAuxData = 0;
2538 return pFrame->pc;
2539 }
2540
2541 /*
2542 ** Close all cursors.
2543 **
2544 ** Also release any dynamic memory held by the VM in the Vdbe.aMem memory
2545 ** cell array. This is necessary as the memory cell array may contain
2546 ** pointers to VdbeFrame objects, which may in turn contain pointers to
2547 ** open cursors.
2548 */
closeAllCursors(Vdbe * p)2549 static void closeAllCursors(Vdbe *p){
2550 if( p->pFrame ){
2551 VdbeFrame *pFrame;
2552 for(pFrame=p->pFrame; pFrame->pParent; pFrame=pFrame->pParent);
2553 sqlite3VdbeFrameRestore(pFrame);
2554 p->pFrame = 0;
2555 p->nFrame = 0;
2556 }
2557 assert( p->nFrame==0 );
2558 closeCursorsInFrame(p);
2559 if( p->aMem ){
2560 releaseMemArray(p->aMem, p->nMem);
2561 }
2562 while( p->pDelFrame ){
2563 VdbeFrame *pDel = p->pDelFrame;
2564 p->pDelFrame = pDel->pParent;
2565 sqlite3VdbeFrameDelete(pDel);
2566 }
2567
2568 /* Delete any auxdata allocations made by the VM */
2569 if( p->pAuxData ) sqlite3VdbeDeleteAuxData(p->db, &p->pAuxData, -1, 0);
2570 assert( p->pAuxData==0 );
2571 }
2572
2573 /*
2574 ** Set the number of result columns that will be returned by this SQL
2575 ** statement. This is now set at compile time, rather than during
2576 ** execution of the vdbe program so that sqlite3_column_count() can
2577 ** be called on an SQL statement before sqlite3_step().
2578 */
sqlite3VdbeSetNumCols(Vdbe * p,int nResColumn)2579 void sqlite3VdbeSetNumCols(Vdbe *p, int nResColumn){
2580 int n;
2581 sqlite3 *db = p->db;
2582
2583 if( p->nResColumn ){
2584 releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
2585 sqlite3DbFree(db, p->aColName);
2586 }
2587 n = nResColumn*COLNAME_N;
2588 p->nResColumn = (u16)nResColumn;
2589 p->aColName = (Mem*)sqlite3DbMallocRawNN(db, sizeof(Mem)*n );
2590 if( p->aColName==0 ) return;
2591 initMemArray(p->aColName, n, db, MEM_Null);
2592 }
2593
2594 /*
2595 ** Set the name of the idx'th column to be returned by the SQL statement.
2596 ** zName must be a pointer to a nul terminated string.
2597 **
2598 ** This call must be made after a call to sqlite3VdbeSetNumCols().
2599 **
2600 ** The final parameter, xDel, must be one of SQLITE_DYNAMIC, SQLITE_STATIC
2601 ** or SQLITE_TRANSIENT. If it is SQLITE_DYNAMIC, then the buffer pointed
2602 ** to by zName will be freed by sqlite3DbFree() when the vdbe is destroyed.
2603 */
sqlite3VdbeSetColName(Vdbe * p,int idx,int var,const char * zName,void (* xDel)(void *))2604 int sqlite3VdbeSetColName(
2605 Vdbe *p, /* Vdbe being configured */
2606 int idx, /* Index of column zName applies to */
2607 int var, /* One of the COLNAME_* constants */
2608 const char *zName, /* Pointer to buffer containing name */
2609 void (*xDel)(void*) /* Memory management strategy for zName */
2610 ){
2611 int rc;
2612 Mem *pColName;
2613 assert( idx<p->nResColumn );
2614 assert( var<COLNAME_N );
2615 if( p->db->mallocFailed ){
2616 assert( !zName || xDel!=SQLITE_DYNAMIC );
2617 return SQLITE_NOMEM_BKPT;
2618 }
2619 assert( p->aColName!=0 );
2620 pColName = &(p->aColName[idx+var*p->nResColumn]);
2621 rc = sqlite3VdbeMemSetStr(pColName, zName, -1, SQLITE_UTF8, xDel);
2622 assert( rc!=0 || !zName || (pColName->flags&MEM_Term)!=0 );
2623 return rc;
2624 }
2625
2626 /*
2627 ** A read or write transaction may or may not be active on database handle
2628 ** db. If a transaction is active, commit it. If there is a
2629 ** write-transaction spanning more than one database file, this routine
2630 ** takes care of the super-journal trickery.
2631 */
vdbeCommit(sqlite3 * db,Vdbe * p)2632 static int vdbeCommit(sqlite3 *db, Vdbe *p){
2633 int i;
2634 int nTrans = 0; /* Number of databases with an active write-transaction
2635 ** that are candidates for a two-phase commit using a
2636 ** super-journal */
2637 int rc = SQLITE_OK;
2638 int needXcommit = 0;
2639
2640 #ifdef SQLITE_OMIT_VIRTUALTABLE
2641 /* With this option, sqlite3VtabSync() is defined to be simply
2642 ** SQLITE_OK so p is not used.
2643 */
2644 UNUSED_PARAMETER(p);
2645 #endif
2646
2647 /* Before doing anything else, call the xSync() callback for any
2648 ** virtual module tables written in this transaction. This has to
2649 ** be done before determining whether a super-journal file is
2650 ** required, as an xSync() callback may add an attached database
2651 ** to the transaction.
2652 */
2653 rc = sqlite3VtabSync(db, p);
2654
2655 /* This loop determines (a) if the commit hook should be invoked and
2656 ** (b) how many database files have open write transactions, not
2657 ** including the temp database. (b) is important because if more than
2658 ** one database file has an open write transaction, a super-journal
2659 ** file is required for an atomic commit.
2660 */
2661 for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
2662 Btree *pBt = db->aDb[i].pBt;
2663 if( sqlite3BtreeTxnState(pBt)==SQLITE_TXN_WRITE ){
2664 /* Whether or not a database might need a super-journal depends upon
2665 ** its journal mode (among other things). This matrix determines which
2666 ** journal modes use a super-journal and which do not */
2667 static const u8 aMJNeeded[] = {
2668 /* DELETE */ 1,
2669 /* PERSIST */ 1,
2670 /* OFF */ 0,
2671 /* TRUNCATE */ 1,
2672 /* MEMORY */ 0,
2673 /* WAL */ 0
2674 };
2675 Pager *pPager; /* Pager associated with pBt */
2676 needXcommit = 1;
2677 sqlite3BtreeEnter(pBt);
2678 pPager = sqlite3BtreePager(pBt);
2679 if( db->aDb[i].safety_level!=PAGER_SYNCHRONOUS_OFF
2680 && aMJNeeded[sqlite3PagerGetJournalMode(pPager)]
2681 && sqlite3PagerIsMemdb(pPager)==0
2682 ){
2683 assert( i!=1 );
2684 nTrans++;
2685 }
2686 rc = sqlite3PagerExclusiveLock(pPager);
2687 sqlite3BtreeLeave(pBt);
2688 }
2689 }
2690 if( rc!=SQLITE_OK ){
2691 return rc;
2692 }
2693
2694 /* If there are any write-transactions at all, invoke the commit hook */
2695 if( needXcommit && db->xCommitCallback ){
2696 rc = db->xCommitCallback(db->pCommitArg);
2697 if( rc ){
2698 return SQLITE_CONSTRAINT_COMMITHOOK;
2699 }
2700 }
2701
2702 /* The simple case - no more than one database file (not counting the
2703 ** TEMP database) has a transaction active. There is no need for the
2704 ** super-journal.
2705 **
2706 ** If the return value of sqlite3BtreeGetFilename() is a zero length
2707 ** string, it means the main database is :memory: or a temp file. In
2708 ** that case we do not support atomic multi-file commits, so use the
2709 ** simple case then too.
2710 */
2711 if( 0==sqlite3Strlen30(sqlite3BtreeGetFilename(db->aDb[0].pBt))
2712 || nTrans<=1
2713 ){
2714 for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
2715 Btree *pBt = db->aDb[i].pBt;
2716 if( pBt ){
2717 rc = sqlite3BtreeCommitPhaseOne(pBt, 0);
2718 }
2719 }
2720
2721 /* Do the commit only if all databases successfully complete phase 1.
2722 ** If one of the BtreeCommitPhaseOne() calls fails, this indicates an
2723 ** IO error while deleting or truncating a journal file. It is unlikely,
2724 ** but could happen. In this case abandon processing and return the error.
2725 */
2726 for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
2727 Btree *pBt = db->aDb[i].pBt;
2728 if( pBt ){
2729 rc = sqlite3BtreeCommitPhaseTwo(pBt, 0);
2730 }
2731 }
2732 if( rc==SQLITE_OK ){
2733 sqlite3VtabCommit(db);
2734 }
2735 }
2736
2737 /* The complex case - There is a multi-file write-transaction active.
2738 ** This requires a super-journal file to ensure the transaction is
2739 ** committed atomically.
2740 */
2741 #ifndef SQLITE_OMIT_DISKIO
2742 else{
2743 sqlite3_vfs *pVfs = db->pVfs;
2744 char *zSuper = 0; /* File-name for the super-journal */
2745 char const *zMainFile = sqlite3BtreeGetFilename(db->aDb[0].pBt);
2746 sqlite3_file *pSuperJrnl = 0;
2747 i64 offset = 0;
2748 int res;
2749 int retryCount = 0;
2750 int nMainFile;
2751
2752 /* Select a super-journal file name */
2753 nMainFile = sqlite3Strlen30(zMainFile);
2754 zSuper = sqlite3MPrintf(db, "%.4c%s%.16c", 0,zMainFile,0);
2755 if( zSuper==0 ) return SQLITE_NOMEM_BKPT;
2756 zSuper += 4;
2757 do {
2758 u32 iRandom;
2759 if( retryCount ){
2760 if( retryCount>100 ){
2761 sqlite3_log(SQLITE_FULL, "MJ delete: %s", zSuper);
2762 sqlite3OsDelete(pVfs, zSuper, 0);
2763 break;
2764 }else if( retryCount==1 ){
2765 sqlite3_log(SQLITE_FULL, "MJ collide: %s", zSuper);
2766 }
2767 }
2768 retryCount++;
2769 sqlite3_randomness(sizeof(iRandom), &iRandom);
2770 sqlite3_snprintf(13, &zSuper[nMainFile], "-mj%06X9%02X",
2771 (iRandom>>8)&0xffffff, iRandom&0xff);
2772 /* The antipenultimate character of the super-journal name must
2773 ** be "9" to avoid name collisions when using 8+3 filenames. */
2774 assert( zSuper[sqlite3Strlen30(zSuper)-3]=='9' );
2775 sqlite3FileSuffix3(zMainFile, zSuper);
2776 rc = sqlite3OsAccess(pVfs, zSuper, SQLITE_ACCESS_EXISTS, &res);
2777 }while( rc==SQLITE_OK && res );
2778 if( rc==SQLITE_OK ){
2779 /* Open the super-journal. */
2780 rc = sqlite3OsOpenMalloc(pVfs, zSuper, &pSuperJrnl,
2781 SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|
2782 SQLITE_OPEN_EXCLUSIVE|SQLITE_OPEN_SUPER_JOURNAL, 0
2783 );
2784 }
2785 if( rc!=SQLITE_OK ){
2786 sqlite3DbFree(db, zSuper-4);
2787 return rc;
2788 }
2789
2790 /* Write the name of each database file in the transaction into the new
2791 ** super-journal file. If an error occurs at this point close
2792 ** and delete the super-journal file. All the individual journal files
2793 ** still have 'null' as the super-journal pointer, so they will roll
2794 ** back independently if a failure occurs.
2795 */
2796 for(i=0; i<db->nDb; i++){
2797 Btree *pBt = db->aDb[i].pBt;
2798 if( sqlite3BtreeTxnState(pBt)==SQLITE_TXN_WRITE ){
2799 char const *zFile = sqlite3BtreeGetJournalname(pBt);
2800 if( zFile==0 ){
2801 continue; /* Ignore TEMP and :memory: databases */
2802 }
2803 assert( zFile[0]!=0 );
2804 rc = sqlite3OsWrite(pSuperJrnl, zFile, sqlite3Strlen30(zFile)+1,offset);
2805 offset += sqlite3Strlen30(zFile)+1;
2806 if( rc!=SQLITE_OK ){
2807 sqlite3OsCloseFree(pSuperJrnl);
2808 sqlite3OsDelete(pVfs, zSuper, 0);
2809 sqlite3DbFree(db, zSuper-4);
2810 return rc;
2811 }
2812 }
2813 }
2814
2815 /* Sync the super-journal file. If the IOCAP_SEQUENTIAL device
2816 ** flag is set this is not required.
2817 */
2818 if( 0==(sqlite3OsDeviceCharacteristics(pSuperJrnl)&SQLITE_IOCAP_SEQUENTIAL)
2819 && SQLITE_OK!=(rc = sqlite3OsSync(pSuperJrnl, SQLITE_SYNC_NORMAL))
2820 ){
2821 sqlite3OsCloseFree(pSuperJrnl);
2822 sqlite3OsDelete(pVfs, zSuper, 0);
2823 sqlite3DbFree(db, zSuper-4);
2824 return rc;
2825 }
2826
2827 /* Sync all the db files involved in the transaction. The same call
2828 ** sets the super-journal pointer in each individual journal. If
2829 ** an error occurs here, do not delete the super-journal file.
2830 **
2831 ** If the error occurs during the first call to
2832 ** sqlite3BtreeCommitPhaseOne(), then there is a chance that the
2833 ** super-journal file will be orphaned. But we cannot delete it,
2834 ** in case the super-journal file name was written into the journal
2835 ** file before the failure occurred.
2836 */
2837 for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
2838 Btree *pBt = db->aDb[i].pBt;
2839 if( pBt ){
2840 rc = sqlite3BtreeCommitPhaseOne(pBt, zSuper);
2841 }
2842 }
2843 sqlite3OsCloseFree(pSuperJrnl);
2844 assert( rc!=SQLITE_BUSY );
2845 if( rc!=SQLITE_OK ){
2846 sqlite3DbFree(db, zSuper-4);
2847 return rc;
2848 }
2849
2850 /* Delete the super-journal file. This commits the transaction. After
2851 ** doing this the directory is synced again before any individual
2852 ** transaction files are deleted.
2853 */
2854 rc = sqlite3OsDelete(pVfs, zSuper, 1);
2855 sqlite3DbFree(db, zSuper-4);
2856 zSuper = 0;
2857 if( rc ){
2858 return rc;
2859 }
2860
2861 /* All files and directories have already been synced, so the following
2862 ** calls to sqlite3BtreeCommitPhaseTwo() are only closing files and
2863 ** deleting or truncating journals. If something goes wrong while
2864 ** this is happening we don't really care. The integrity of the
2865 ** transaction is already guaranteed, but some stray 'cold' journals
2866 ** may be lying around. Returning an error code won't help matters.
2867 */
2868 disable_simulated_io_errors();
2869 sqlite3BeginBenignMalloc();
2870 for(i=0; i<db->nDb; i++){
2871 Btree *pBt = db->aDb[i].pBt;
2872 if( pBt ){
2873 sqlite3BtreeCommitPhaseTwo(pBt, 1);
2874 }
2875 }
2876 sqlite3EndBenignMalloc();
2877 enable_simulated_io_errors();
2878
2879 sqlite3VtabCommit(db);
2880 }
2881 #endif
2882
2883 return rc;
2884 }
2885
2886 /*
2887 ** This routine checks that the sqlite3.nVdbeActive count variable
2888 ** matches the number of vdbe's in the list sqlite3.pVdbe that are
2889 ** currently active. An assertion fails if the two counts do not match.
2890 ** This is an internal self-check only - it is not an essential processing
2891 ** step.
2892 **
2893 ** This is a no-op if NDEBUG is defined.
2894 */
2895 #ifndef NDEBUG
checkActiveVdbeCnt(sqlite3 * db)2896 static void checkActiveVdbeCnt(sqlite3 *db){
2897 Vdbe *p;
2898 int cnt = 0;
2899 int nWrite = 0;
2900 int nRead = 0;
2901 p = db->pVdbe;
2902 while( p ){
2903 if( sqlite3_stmt_busy((sqlite3_stmt*)p) ){
2904 cnt++;
2905 if( p->readOnly==0 ) nWrite++;
2906 if( p->bIsReader ) nRead++;
2907 }
2908 p = p->pNext;
2909 }
2910 assert( cnt==db->nVdbeActive );
2911 assert( nWrite==db->nVdbeWrite );
2912 assert( nRead==db->nVdbeRead );
2913 }
2914 #else
2915 #define checkActiveVdbeCnt(x)
2916 #endif
2917
2918 /*
2919 ** If the Vdbe passed as the first argument opened a statement-transaction,
2920 ** close it now. Argument eOp must be either SAVEPOINT_ROLLBACK or
2921 ** SAVEPOINT_RELEASE. If it is SAVEPOINT_ROLLBACK, then the statement
2922 ** transaction is rolled back. If eOp is SAVEPOINT_RELEASE, then the
2923 ** statement transaction is committed.
2924 **
2925 ** If an IO error occurs, an SQLITE_IOERR_XXX error code is returned.
2926 ** Otherwise SQLITE_OK.
2927 */
vdbeCloseStatement(Vdbe * p,int eOp)2928 static SQLITE_NOINLINE int vdbeCloseStatement(Vdbe *p, int eOp){
2929 sqlite3 *const db = p->db;
2930 int rc = SQLITE_OK;
2931 int i;
2932 const int iSavepoint = p->iStatement-1;
2933
2934 assert( eOp==SAVEPOINT_ROLLBACK || eOp==SAVEPOINT_RELEASE);
2935 assert( db->nStatement>0 );
2936 assert( p->iStatement==(db->nStatement+db->nSavepoint) );
2937
2938 for(i=0; i<db->nDb; i++){
2939 int rc2 = SQLITE_OK;
2940 Btree *pBt = db->aDb[i].pBt;
2941 if( pBt ){
2942 if( eOp==SAVEPOINT_ROLLBACK ){
2943 rc2 = sqlite3BtreeSavepoint(pBt, SAVEPOINT_ROLLBACK, iSavepoint);
2944 }
2945 if( rc2==SQLITE_OK ){
2946 rc2 = sqlite3BtreeSavepoint(pBt, SAVEPOINT_RELEASE, iSavepoint);
2947 }
2948 if( rc==SQLITE_OK ){
2949 rc = rc2;
2950 }
2951 }
2952 }
2953 db->nStatement--;
2954 p->iStatement = 0;
2955
2956 if( rc==SQLITE_OK ){
2957 if( eOp==SAVEPOINT_ROLLBACK ){
2958 rc = sqlite3VtabSavepoint(db, SAVEPOINT_ROLLBACK, iSavepoint);
2959 }
2960 if( rc==SQLITE_OK ){
2961 rc = sqlite3VtabSavepoint(db, SAVEPOINT_RELEASE, iSavepoint);
2962 }
2963 }
2964
2965 /* If the statement transaction is being rolled back, also restore the
2966 ** database handles deferred constraint counter to the value it had when
2967 ** the statement transaction was opened. */
2968 if( eOp==SAVEPOINT_ROLLBACK ){
2969 db->nDeferredCons = p->nStmtDefCons;
2970 db->nDeferredImmCons = p->nStmtDefImmCons;
2971 }
2972 return rc;
2973 }
sqlite3VdbeCloseStatement(Vdbe * p,int eOp)2974 int sqlite3VdbeCloseStatement(Vdbe *p, int eOp){
2975 if( p->db->nStatement && p->iStatement ){
2976 return vdbeCloseStatement(p, eOp);
2977 }
2978 return SQLITE_OK;
2979 }
2980
2981
2982 /*
2983 ** This function is called when a transaction opened by the database
2984 ** handle associated with the VM passed as an argument is about to be
2985 ** committed. If there are outstanding deferred foreign key constraint
2986 ** violations, return SQLITE_ERROR. Otherwise, SQLITE_OK.
2987 **
2988 ** If there are outstanding FK violations and this function returns
2989 ** SQLITE_ERROR, set the result of the VM to SQLITE_CONSTRAINT_FOREIGNKEY
2990 ** and write an error message to it. Then return SQLITE_ERROR.
2991 */
2992 #ifndef SQLITE_OMIT_FOREIGN_KEY
sqlite3VdbeCheckFk(Vdbe * p,int deferred)2993 int sqlite3VdbeCheckFk(Vdbe *p, int deferred){
2994 sqlite3 *db = p->db;
2995 if( (deferred && (db->nDeferredCons+db->nDeferredImmCons)>0)
2996 || (!deferred && p->nFkConstraint>0)
2997 ){
2998 p->rc = SQLITE_CONSTRAINT_FOREIGNKEY;
2999 p->errorAction = OE_Abort;
3000 sqlite3VdbeError(p, "FOREIGN KEY constraint failed");
3001 return SQLITE_ERROR;
3002 }
3003 return SQLITE_OK;
3004 }
3005 #endif
3006
3007 /*
3008 ** This routine is called the when a VDBE tries to halt. If the VDBE
3009 ** has made changes and is in autocommit mode, then commit those
3010 ** changes. If a rollback is needed, then do the rollback.
3011 **
3012 ** This routine is the only way to move the state of a VM from
3013 ** SQLITE_MAGIC_RUN to SQLITE_MAGIC_HALT. It is harmless to
3014 ** call this on a VM that is in the SQLITE_MAGIC_HALT state.
3015 **
3016 ** Return an error code. If the commit could not complete because of
3017 ** lock contention, return SQLITE_BUSY. If SQLITE_BUSY is returned, it
3018 ** means the close did not happen and needs to be repeated.
3019 */
sqlite3VdbeHalt(Vdbe * p)3020 int sqlite3VdbeHalt(Vdbe *p){
3021 int rc; /* Used to store transient return codes */
3022 sqlite3 *db = p->db;
3023
3024 /* This function contains the logic that determines if a statement or
3025 ** transaction will be committed or rolled back as a result of the
3026 ** execution of this virtual machine.
3027 **
3028 ** If any of the following errors occur:
3029 **
3030 ** SQLITE_NOMEM
3031 ** SQLITE_IOERR
3032 ** SQLITE_FULL
3033 ** SQLITE_INTERRUPT
3034 **
3035 ** Then the internal cache might have been left in an inconsistent
3036 ** state. We need to rollback the statement transaction, if there is
3037 ** one, or the complete transaction if there is no statement transaction.
3038 */
3039
3040 if( p->iVdbeMagic!=VDBE_MAGIC_RUN ){
3041 return SQLITE_OK;
3042 }
3043 if( db->mallocFailed ){
3044 p->rc = SQLITE_NOMEM_BKPT;
3045 }
3046 closeAllCursors(p);
3047 checkActiveVdbeCnt(db);
3048
3049 /* No commit or rollback needed if the program never started or if the
3050 ** SQL statement does not read or write a database file. */
3051 if( p->pc>=0 && p->bIsReader ){
3052 int mrc; /* Primary error code from p->rc */
3053 int eStatementOp = 0;
3054 int isSpecialError; /* Set to true if a 'special' error */
3055
3056 /* Lock all btrees used by the statement */
3057 sqlite3VdbeEnter(p);
3058
3059 /* Check for one of the special errors */
3060 mrc = p->rc & 0xff;
3061 isSpecialError = mrc==SQLITE_NOMEM || mrc==SQLITE_IOERR
3062 || mrc==SQLITE_INTERRUPT || mrc==SQLITE_FULL;
3063 if( isSpecialError ){
3064 /* If the query was read-only and the error code is SQLITE_INTERRUPT,
3065 ** no rollback is necessary. Otherwise, at least a savepoint
3066 ** transaction must be rolled back to restore the database to a
3067 ** consistent state.
3068 **
3069 ** Even if the statement is read-only, it is important to perform
3070 ** a statement or transaction rollback operation. If the error
3071 ** occurred while writing to the journal, sub-journal or database
3072 ** file as part of an effort to free up cache space (see function
3073 ** pagerStress() in pager.c), the rollback is required to restore
3074 ** the pager to a consistent state.
3075 */
3076 if( !p->readOnly || mrc!=SQLITE_INTERRUPT ){
3077 if( (mrc==SQLITE_NOMEM || mrc==SQLITE_FULL) && p->usesStmtJournal ){
3078 eStatementOp = SAVEPOINT_ROLLBACK;
3079 }else{
3080 /* We are forced to roll back the active transaction. Before doing
3081 ** so, abort any other statements this handle currently has active.
3082 */
3083 sqlite3RollbackAll(db, SQLITE_ABORT_ROLLBACK);
3084 sqlite3CloseSavepoints(db);
3085 db->autoCommit = 1;
3086 p->nChange = 0;
3087 }
3088 }
3089 }
3090
3091 /* Check for immediate foreign key violations. */
3092 if( p->rc==SQLITE_OK || (p->errorAction==OE_Fail && !isSpecialError) ){
3093 sqlite3VdbeCheckFk(p, 0);
3094 }
3095
3096 /* If the auto-commit flag is set and this is the only active writer
3097 ** VM, then we do either a commit or rollback of the current transaction.
3098 **
3099 ** Note: This block also runs if one of the special errors handled
3100 ** above has occurred.
3101 */
3102 if( !sqlite3VtabInSync(db)
3103 && db->autoCommit
3104 && db->nVdbeWrite==(p->readOnly==0)
3105 ){
3106 if( p->rc==SQLITE_OK || (p->errorAction==OE_Fail && !isSpecialError) ){
3107 rc = sqlite3VdbeCheckFk(p, 1);
3108 if( rc!=SQLITE_OK ){
3109 if( NEVER(p->readOnly) ){
3110 sqlite3VdbeLeave(p);
3111 return SQLITE_ERROR;
3112 }
3113 rc = SQLITE_CONSTRAINT_FOREIGNKEY;
3114 }else{
3115 /* The auto-commit flag is true, the vdbe program was successful
3116 ** or hit an 'OR FAIL' constraint and there are no deferred foreign
3117 ** key constraints to hold up the transaction. This means a commit
3118 ** is required. */
3119 rc = vdbeCommit(db, p);
3120 }
3121 if( rc==SQLITE_BUSY && p->readOnly ){
3122 sqlite3VdbeLeave(p);
3123 return SQLITE_BUSY;
3124 }else if( rc!=SQLITE_OK ){
3125 p->rc = rc;
3126 sqlite3RollbackAll(db, SQLITE_OK);
3127 p->nChange = 0;
3128 }else{
3129 db->nDeferredCons = 0;
3130 db->nDeferredImmCons = 0;
3131 db->flags &= ~(u64)SQLITE_DeferFKs;
3132 sqlite3CommitInternalChanges(db);
3133 }
3134 }else{
3135 sqlite3RollbackAll(db, SQLITE_OK);
3136 p->nChange = 0;
3137 }
3138 db->nStatement = 0;
3139 }else if( eStatementOp==0 ){
3140 if( p->rc==SQLITE_OK || p->errorAction==OE_Fail ){
3141 eStatementOp = SAVEPOINT_RELEASE;
3142 }else if( p->errorAction==OE_Abort ){
3143 eStatementOp = SAVEPOINT_ROLLBACK;
3144 }else{
3145 sqlite3RollbackAll(db, SQLITE_ABORT_ROLLBACK);
3146 sqlite3CloseSavepoints(db);
3147 db->autoCommit = 1;
3148 p->nChange = 0;
3149 }
3150 }
3151
3152 /* If eStatementOp is non-zero, then a statement transaction needs to
3153 ** be committed or rolled back. Call sqlite3VdbeCloseStatement() to
3154 ** do so. If this operation returns an error, and the current statement
3155 ** error code is SQLITE_OK or SQLITE_CONSTRAINT, then promote the
3156 ** current statement error code.
3157 */
3158 if( eStatementOp ){
3159 rc = sqlite3VdbeCloseStatement(p, eStatementOp);
3160 if( rc ){
3161 if( p->rc==SQLITE_OK || (p->rc&0xff)==SQLITE_CONSTRAINT ){
3162 p->rc = rc;
3163 sqlite3DbFree(db, p->zErrMsg);
3164 p->zErrMsg = 0;
3165 }
3166 sqlite3RollbackAll(db, SQLITE_ABORT_ROLLBACK);
3167 sqlite3CloseSavepoints(db);
3168 db->autoCommit = 1;
3169 p->nChange = 0;
3170 }
3171 }
3172
3173 /* If this was an INSERT, UPDATE or DELETE and no statement transaction
3174 ** has been rolled back, update the database connection change-counter.
3175 */
3176 if( p->changeCntOn ){
3177 if( eStatementOp!=SAVEPOINT_ROLLBACK ){
3178 sqlite3VdbeSetChanges(db, p->nChange);
3179 }else{
3180 sqlite3VdbeSetChanges(db, 0);
3181 }
3182 p->nChange = 0;
3183 }
3184
3185 /* Release the locks */
3186 sqlite3VdbeLeave(p);
3187 }
3188
3189 /* We have successfully halted and closed the VM. Record this fact. */
3190 if( p->pc>=0 ){
3191 db->nVdbeActive--;
3192 if( !p->readOnly ) db->nVdbeWrite--;
3193 if( p->bIsReader ) db->nVdbeRead--;
3194 assert( db->nVdbeActive>=db->nVdbeRead );
3195 assert( db->nVdbeRead>=db->nVdbeWrite );
3196 assert( db->nVdbeWrite>=0 );
3197 }
3198 p->iVdbeMagic = VDBE_MAGIC_HALT;
3199 checkActiveVdbeCnt(db);
3200 if( db->mallocFailed ){
3201 p->rc = SQLITE_NOMEM_BKPT;
3202 }
3203
3204 /* If the auto-commit flag is set to true, then any locks that were held
3205 ** by connection db have now been released. Call sqlite3ConnectionUnlocked()
3206 ** to invoke any required unlock-notify callbacks.
3207 */
3208 if( db->autoCommit ){
3209 sqlite3ConnectionUnlocked(db);
3210 }
3211
3212 assert( db->nVdbeActive>0 || db->autoCommit==0 || db->nStatement==0 );
3213 return (p->rc==SQLITE_BUSY ? SQLITE_BUSY : SQLITE_OK);
3214 }
3215
3216
3217 /*
3218 ** Each VDBE holds the result of the most recent sqlite3_step() call
3219 ** in p->rc. This routine sets that result back to SQLITE_OK.
3220 */
sqlite3VdbeResetStepResult(Vdbe * p)3221 void sqlite3VdbeResetStepResult(Vdbe *p){
3222 p->rc = SQLITE_OK;
3223 }
3224
3225 /*
3226 ** Copy the error code and error message belonging to the VDBE passed
3227 ** as the first argument to its database handle (so that they will be
3228 ** returned by calls to sqlite3_errcode() and sqlite3_errmsg()).
3229 **
3230 ** This function does not clear the VDBE error code or message, just
3231 ** copies them to the database handle.
3232 */
sqlite3VdbeTransferError(Vdbe * p)3233 int sqlite3VdbeTransferError(Vdbe *p){
3234 sqlite3 *db = p->db;
3235 int rc = p->rc;
3236 if( p->zErrMsg ){
3237 db->bBenignMalloc++;
3238 sqlite3BeginBenignMalloc();
3239 if( db->pErr==0 ) db->pErr = sqlite3ValueNew(db);
3240 sqlite3ValueSetStr(db->pErr, -1, p->zErrMsg, SQLITE_UTF8, SQLITE_TRANSIENT);
3241 sqlite3EndBenignMalloc();
3242 db->bBenignMalloc--;
3243 }else if( db->pErr ){
3244 sqlite3ValueSetNull(db->pErr);
3245 }
3246 db->errCode = rc;
3247 return rc;
3248 }
3249
3250 #ifdef SQLITE_ENABLE_SQLLOG
3251 /*
3252 ** If an SQLITE_CONFIG_SQLLOG hook is registered and the VM has been run,
3253 ** invoke it.
3254 */
vdbeInvokeSqllog(Vdbe * v)3255 static void vdbeInvokeSqllog(Vdbe *v){
3256 if( sqlite3GlobalConfig.xSqllog && v->rc==SQLITE_OK && v->zSql && v->pc>=0 ){
3257 char *zExpanded = sqlite3VdbeExpandSql(v, v->zSql);
3258 assert( v->db->init.busy==0 );
3259 if( zExpanded ){
3260 sqlite3GlobalConfig.xSqllog(
3261 sqlite3GlobalConfig.pSqllogArg, v->db, zExpanded, 1
3262 );
3263 sqlite3DbFree(v->db, zExpanded);
3264 }
3265 }
3266 }
3267 #else
3268 # define vdbeInvokeSqllog(x)
3269 #endif
3270
3271 /*
3272 ** Clean up a VDBE after execution but do not delete the VDBE just yet.
3273 ** Write any error messages into *pzErrMsg. Return the result code.
3274 **
3275 ** After this routine is run, the VDBE should be ready to be executed
3276 ** again.
3277 **
3278 ** To look at it another way, this routine resets the state of the
3279 ** virtual machine from VDBE_MAGIC_RUN or VDBE_MAGIC_HALT back to
3280 ** VDBE_MAGIC_INIT.
3281 */
sqlite3VdbeReset(Vdbe * p)3282 int sqlite3VdbeReset(Vdbe *p){
3283 #if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
3284 int i;
3285 #endif
3286
3287 sqlite3 *db;
3288 db = p->db;
3289
3290 /* If the VM did not run to completion or if it encountered an
3291 ** error, then it might not have been halted properly. So halt
3292 ** it now.
3293 */
3294 sqlite3VdbeHalt(p);
3295
3296 /* If the VDBE has been run even partially, then transfer the error code
3297 ** and error message from the VDBE into the main database structure. But
3298 ** if the VDBE has just been set to run but has not actually executed any
3299 ** instructions yet, leave the main database error information unchanged.
3300 */
3301 if( p->pc>=0 ){
3302 vdbeInvokeSqllog(p);
3303 if( db->pErr || p->zErrMsg ){
3304 sqlite3VdbeTransferError(p);
3305 }else{
3306 db->errCode = p->rc;
3307 }
3308 if( p->runOnlyOnce ) p->expired = 1;
3309 }else if( p->rc && p->expired ){
3310 /* The expired flag was set on the VDBE before the first call
3311 ** to sqlite3_step(). For consistency (since sqlite3_step() was
3312 ** called), set the database error in this case as well.
3313 */
3314 sqlite3ErrorWithMsg(db, p->rc, p->zErrMsg ? "%s" : 0, p->zErrMsg);
3315 }
3316
3317 /* Reset register contents and reclaim error message memory.
3318 */
3319 #ifdef SQLITE_DEBUG
3320 /* Execute assert() statements to ensure that the Vdbe.apCsr[] and
3321 ** Vdbe.aMem[] arrays have already been cleaned up. */
3322 if( p->apCsr ) for(i=0; i<p->nCursor; i++) assert( p->apCsr[i]==0 );
3323 if( p->aMem ){
3324 for(i=0; i<p->nMem; i++) assert( p->aMem[i].flags==MEM_Undefined );
3325 }
3326 #endif
3327 if( p->zErrMsg ){
3328 sqlite3DbFree(db, p->zErrMsg);
3329 p->zErrMsg = 0;
3330 }
3331 p->pResultSet = 0;
3332 #ifdef SQLITE_DEBUG
3333 p->nWrite = 0;
3334 #endif
3335
3336 /* Save profiling information from this VDBE run.
3337 */
3338 #ifdef VDBE_PROFILE
3339 {
3340 FILE *out = fopen("vdbe_profile.out", "a");
3341 if( out ){
3342 fprintf(out, "---- ");
3343 for(i=0; i<p->nOp; i++){
3344 fprintf(out, "%02x", p->aOp[i].opcode);
3345 }
3346 fprintf(out, "\n");
3347 if( p->zSql ){
3348 char c, pc = 0;
3349 fprintf(out, "-- ");
3350 for(i=0; (c = p->zSql[i])!=0; i++){
3351 if( pc=='\n' ) fprintf(out, "-- ");
3352 putc(c, out);
3353 pc = c;
3354 }
3355 if( pc!='\n' ) fprintf(out, "\n");
3356 }
3357 for(i=0; i<p->nOp; i++){
3358 char zHdr[100];
3359 sqlite3_snprintf(sizeof(zHdr), zHdr, "%6u %12llu %8llu ",
3360 p->aOp[i].cnt,
3361 p->aOp[i].cycles,
3362 p->aOp[i].cnt>0 ? p->aOp[i].cycles/p->aOp[i].cnt : 0
3363 );
3364 fprintf(out, "%s", zHdr);
3365 sqlite3VdbePrintOp(out, i, &p->aOp[i]);
3366 }
3367 fclose(out);
3368 }
3369 }
3370 #endif
3371 p->iVdbeMagic = VDBE_MAGIC_RESET;
3372 return p->rc & db->errMask;
3373 }
3374
3375 /*
3376 ** Clean up and delete a VDBE after execution. Return an integer which is
3377 ** the result code. Write any error message text into *pzErrMsg.
3378 */
sqlite3VdbeFinalize(Vdbe * p)3379 int sqlite3VdbeFinalize(Vdbe *p){
3380 int rc = SQLITE_OK;
3381 if( p->iVdbeMagic==VDBE_MAGIC_RUN || p->iVdbeMagic==VDBE_MAGIC_HALT ){
3382 rc = sqlite3VdbeReset(p);
3383 assert( (rc & p->db->errMask)==rc );
3384 }
3385 sqlite3VdbeDelete(p);
3386 return rc;
3387 }
3388
3389 /*
3390 ** If parameter iOp is less than zero, then invoke the destructor for
3391 ** all auxiliary data pointers currently cached by the VM passed as
3392 ** the first argument.
3393 **
3394 ** Or, if iOp is greater than or equal to zero, then the destructor is
3395 ** only invoked for those auxiliary data pointers created by the user
3396 ** function invoked by the OP_Function opcode at instruction iOp of
3397 ** VM pVdbe, and only then if:
3398 **
3399 ** * the associated function parameter is the 32nd or later (counting
3400 ** from left to right), or
3401 **
3402 ** * the corresponding bit in argument mask is clear (where the first
3403 ** function parameter corresponds to bit 0 etc.).
3404 */
sqlite3VdbeDeleteAuxData(sqlite3 * db,AuxData ** pp,int iOp,int mask)3405 void sqlite3VdbeDeleteAuxData(sqlite3 *db, AuxData **pp, int iOp, int mask){
3406 while( *pp ){
3407 AuxData *pAux = *pp;
3408 if( (iOp<0)
3409 || (pAux->iAuxOp==iOp
3410 && pAux->iAuxArg>=0
3411 && (pAux->iAuxArg>31 || !(mask & MASKBIT32(pAux->iAuxArg))))
3412 ){
3413 testcase( pAux->iAuxArg==31 );
3414 if( pAux->xDeleteAux ){
3415 pAux->xDeleteAux(pAux->pAux);
3416 }
3417 *pp = pAux->pNextAux;
3418 sqlite3DbFree(db, pAux);
3419 }else{
3420 pp= &pAux->pNextAux;
3421 }
3422 }
3423 }
3424
3425 /*
3426 ** Free all memory associated with the Vdbe passed as the second argument,
3427 ** except for object itself, which is preserved.
3428 **
3429 ** The difference between this function and sqlite3VdbeDelete() is that
3430 ** VdbeDelete() also unlinks the Vdbe from the list of VMs associated with
3431 ** the database connection and frees the object itself.
3432 */
sqlite3VdbeClearObject(sqlite3 * db,Vdbe * p)3433 void sqlite3VdbeClearObject(sqlite3 *db, Vdbe *p){
3434 SubProgram *pSub, *pNext;
3435 assert( p->db==0 || p->db==db );
3436 releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
3437 for(pSub=p->pProgram; pSub; pSub=pNext){
3438 pNext = pSub->pNext;
3439 vdbeFreeOpArray(db, pSub->aOp, pSub->nOp);
3440 sqlite3DbFree(db, pSub);
3441 }
3442 if( p->iVdbeMagic!=VDBE_MAGIC_INIT ){
3443 releaseMemArray(p->aVar, p->nVar);
3444 sqlite3DbFree(db, p->pVList);
3445 sqlite3DbFree(db, p->pFree);
3446 }
3447 vdbeFreeOpArray(db, p->aOp, p->nOp);
3448 sqlite3DbFree(db, p->aColName);
3449 sqlite3DbFree(db, p->zSql);
3450 #ifdef SQLITE_ENABLE_NORMALIZE
3451 sqlite3DbFree(db, p->zNormSql);
3452 {
3453 DblquoteStr *pThis, *pNext;
3454 for(pThis=p->pDblStr; pThis; pThis=pNext){
3455 pNext = pThis->pNextStr;
3456 sqlite3DbFree(db, pThis);
3457 }
3458 }
3459 #endif
3460 #ifdef SQLITE_ENABLE_STMT_SCANSTATUS
3461 {
3462 int i;
3463 for(i=0; i<p->nScan; i++){
3464 sqlite3DbFree(db, p->aScan[i].zName);
3465 }
3466 sqlite3DbFree(db, p->aScan);
3467 }
3468 #endif
3469 }
3470
3471 /*
3472 ** Delete an entire VDBE.
3473 */
sqlite3VdbeDelete(Vdbe * p)3474 void sqlite3VdbeDelete(Vdbe *p){
3475 sqlite3 *db;
3476
3477 assert( p!=0 );
3478 db = p->db;
3479 assert( sqlite3_mutex_held(db->mutex) );
3480 sqlite3VdbeClearObject(db, p);
3481 if( p->pPrev ){
3482 p->pPrev->pNext = p->pNext;
3483 }else{
3484 assert( db->pVdbe==p );
3485 db->pVdbe = p->pNext;
3486 }
3487 if( p->pNext ){
3488 p->pNext->pPrev = p->pPrev;
3489 }
3490 p->iVdbeMagic = VDBE_MAGIC_DEAD;
3491 p->db = 0;
3492 sqlite3DbFreeNN(db, p);
3493 }
3494
3495 /*
3496 ** The cursor "p" has a pending seek operation that has not yet been
3497 ** carried out. Seek the cursor now. If an error occurs, return
3498 ** the appropriate error code.
3499 */
sqlite3VdbeFinishMoveto(VdbeCursor * p)3500 int SQLITE_NOINLINE sqlite3VdbeFinishMoveto(VdbeCursor *p){
3501 int res, rc;
3502 #ifdef SQLITE_TEST
3503 extern int sqlite3_search_count;
3504 #endif
3505 assert( p->deferredMoveto );
3506 assert( p->isTable );
3507 assert( p->eCurType==CURTYPE_BTREE );
3508 rc = sqlite3BtreeMovetoUnpacked(p->uc.pCursor, 0, p->movetoTarget, 0, &res);
3509 if( rc ) return rc;
3510 if( res!=0 ) return SQLITE_CORRUPT_BKPT;
3511 #ifdef SQLITE_TEST
3512 sqlite3_search_count++;
3513 #endif
3514 p->deferredMoveto = 0;
3515 p->cacheStatus = CACHE_STALE;
3516 return SQLITE_OK;
3517 }
3518
3519 /*
3520 ** Something has moved cursor "p" out of place. Maybe the row it was
3521 ** pointed to was deleted out from under it. Or maybe the btree was
3522 ** rebalanced. Whatever the cause, try to restore "p" to the place it
3523 ** is supposed to be pointing. If the row was deleted out from under the
3524 ** cursor, set the cursor to point to a NULL row.
3525 */
handleMovedCursor(VdbeCursor * p)3526 static int SQLITE_NOINLINE handleMovedCursor(VdbeCursor *p){
3527 int isDifferentRow, rc;
3528 assert( p->eCurType==CURTYPE_BTREE );
3529 assert( p->uc.pCursor!=0 );
3530 assert( sqlite3BtreeCursorHasMoved(p->uc.pCursor) );
3531 rc = sqlite3BtreeCursorRestore(p->uc.pCursor, &isDifferentRow);
3532 p->cacheStatus = CACHE_STALE;
3533 if( isDifferentRow ) p->nullRow = 1;
3534 return rc;
3535 }
3536
3537 /*
3538 ** Check to ensure that the cursor is valid. Restore the cursor
3539 ** if need be. Return any I/O error from the restore operation.
3540 */
sqlite3VdbeCursorRestore(VdbeCursor * p)3541 int sqlite3VdbeCursorRestore(VdbeCursor *p){
3542 assert( p->eCurType==CURTYPE_BTREE );
3543 if( sqlite3BtreeCursorHasMoved(p->uc.pCursor) ){
3544 return handleMovedCursor(p);
3545 }
3546 return SQLITE_OK;
3547 }
3548
3549 /*
3550 ** Make sure the cursor p is ready to read or write the row to which it
3551 ** was last positioned. Return an error code if an OOM fault or I/O error
3552 ** prevents us from positioning the cursor to its correct position.
3553 **
3554 ** If a MoveTo operation is pending on the given cursor, then do that
3555 ** MoveTo now. If no move is pending, check to see if the row has been
3556 ** deleted out from under the cursor and if it has, mark the row as
3557 ** a NULL row.
3558 **
3559 ** If the cursor is already pointing to the correct row and that row has
3560 ** not been deleted out from under the cursor, then this routine is a no-op.
3561 */
sqlite3VdbeCursorMoveto(VdbeCursor ** pp,u32 * piCol)3562 int sqlite3VdbeCursorMoveto(VdbeCursor **pp, u32 *piCol){
3563 VdbeCursor *p = *pp;
3564 assert( p->eCurType==CURTYPE_BTREE || p->eCurType==CURTYPE_PSEUDO );
3565 if( p->deferredMoveto ){
3566 u32 iMap;
3567 assert( !p->isEphemeral );
3568 if( p->aAltMap && (iMap = p->aAltMap[1+*piCol])>0 && !p->nullRow ){
3569 *pp = p->pAltCursor;
3570 *piCol = iMap - 1;
3571 return SQLITE_OK;
3572 }
3573 return sqlite3VdbeFinishMoveto(p);
3574 }
3575 if( sqlite3BtreeCursorHasMoved(p->uc.pCursor) ){
3576 return handleMovedCursor(p);
3577 }
3578 return SQLITE_OK;
3579 }
3580
3581 /*
3582 ** The following functions:
3583 **
3584 ** sqlite3VdbeSerialType()
3585 ** sqlite3VdbeSerialTypeLen()
3586 ** sqlite3VdbeSerialLen()
3587 ** sqlite3VdbeSerialPut()
3588 ** sqlite3VdbeSerialGet()
3589 **
3590 ** encapsulate the code that serializes values for storage in SQLite
3591 ** data and index records. Each serialized value consists of a
3592 ** 'serial-type' and a blob of data. The serial type is an 8-byte unsigned
3593 ** integer, stored as a varint.
3594 **
3595 ** In an SQLite index record, the serial type is stored directly before
3596 ** the blob of data that it corresponds to. In a table record, all serial
3597 ** types are stored at the start of the record, and the blobs of data at
3598 ** the end. Hence these functions allow the caller to handle the
3599 ** serial-type and data blob separately.
3600 **
3601 ** The following table describes the various storage classes for data:
3602 **
3603 ** serial type bytes of data type
3604 ** -------------- --------------- ---------------
3605 ** 0 0 NULL
3606 ** 1 1 signed integer
3607 ** 2 2 signed integer
3608 ** 3 3 signed integer
3609 ** 4 4 signed integer
3610 ** 5 6 signed integer
3611 ** 6 8 signed integer
3612 ** 7 8 IEEE float
3613 ** 8 0 Integer constant 0
3614 ** 9 0 Integer constant 1
3615 ** 10,11 reserved for expansion
3616 ** N>=12 and even (N-12)/2 BLOB
3617 ** N>=13 and odd (N-13)/2 text
3618 **
3619 ** The 8 and 9 types were added in 3.3.0, file format 4. Prior versions
3620 ** of SQLite will not understand those serial types.
3621 */
3622
3623 #if 0 /* Inlined into the OP_MakeRecord opcode */
3624 /*
3625 ** Return the serial-type for the value stored in pMem.
3626 **
3627 ** This routine might convert a large MEM_IntReal value into MEM_Real.
3628 **
3629 ** 2019-07-11: The primary user of this subroutine was the OP_MakeRecord
3630 ** opcode in the byte-code engine. But by moving this routine in-line, we
3631 ** can omit some redundant tests and make that opcode a lot faster. So
3632 ** this routine is now only used by the STAT3 logic and STAT3 support has
3633 ** ended. The code is kept here for historical reference only.
3634 */
3635 u32 sqlite3VdbeSerialType(Mem *pMem, int file_format, u32 *pLen){
3636 int flags = pMem->flags;
3637 u32 n;
3638
3639 assert( pLen!=0 );
3640 if( flags&MEM_Null ){
3641 *pLen = 0;
3642 return 0;
3643 }
3644 if( flags&(MEM_Int|MEM_IntReal) ){
3645 /* Figure out whether to use 1, 2, 4, 6 or 8 bytes. */
3646 # define MAX_6BYTE ((((i64)0x00008000)<<32)-1)
3647 i64 i = pMem->u.i;
3648 u64 u;
3649 testcase( flags & MEM_Int );
3650 testcase( flags & MEM_IntReal );
3651 if( i<0 ){
3652 u = ~i;
3653 }else{
3654 u = i;
3655 }
3656 if( u<=127 ){
3657 if( (i&1)==i && file_format>=4 ){
3658 *pLen = 0;
3659 return 8+(u32)u;
3660 }else{
3661 *pLen = 1;
3662 return 1;
3663 }
3664 }
3665 if( u<=32767 ){ *pLen = 2; return 2; }
3666 if( u<=8388607 ){ *pLen = 3; return 3; }
3667 if( u<=2147483647 ){ *pLen = 4; return 4; }
3668 if( u<=MAX_6BYTE ){ *pLen = 6; return 5; }
3669 *pLen = 8;
3670 if( flags&MEM_IntReal ){
3671 /* If the value is IntReal and is going to take up 8 bytes to store
3672 ** as an integer, then we might as well make it an 8-byte floating
3673 ** point value */
3674 pMem->u.r = (double)pMem->u.i;
3675 pMem->flags &= ~MEM_IntReal;
3676 pMem->flags |= MEM_Real;
3677 return 7;
3678 }
3679 return 6;
3680 }
3681 if( flags&MEM_Real ){
3682 *pLen = 8;
3683 return 7;
3684 }
3685 assert( pMem->db->mallocFailed || flags&(MEM_Str|MEM_Blob) );
3686 assert( pMem->n>=0 );
3687 n = (u32)pMem->n;
3688 if( flags & MEM_Zero ){
3689 n += pMem->u.nZero;
3690 }
3691 *pLen = n;
3692 return ((n*2) + 12 + ((flags&MEM_Str)!=0));
3693 }
3694 #endif /* inlined into OP_MakeRecord */
3695
3696 /*
3697 ** The sizes for serial types less than 128
3698 */
3699 static const u8 sqlite3SmallTypeSizes[] = {
3700 /* 0 1 2 3 4 5 6 7 8 9 */
3701 /* 0 */ 0, 1, 2, 3, 4, 6, 8, 8, 0, 0,
3702 /* 10 */ 0, 0, 0, 0, 1, 1, 2, 2, 3, 3,
3703 /* 20 */ 4, 4, 5, 5, 6, 6, 7, 7, 8, 8,
3704 /* 30 */ 9, 9, 10, 10, 11, 11, 12, 12, 13, 13,
3705 /* 40 */ 14, 14, 15, 15, 16, 16, 17, 17, 18, 18,
3706 /* 50 */ 19, 19, 20, 20, 21, 21, 22, 22, 23, 23,
3707 /* 60 */ 24, 24, 25, 25, 26, 26, 27, 27, 28, 28,
3708 /* 70 */ 29, 29, 30, 30, 31, 31, 32, 32, 33, 33,
3709 /* 80 */ 34, 34, 35, 35, 36, 36, 37, 37, 38, 38,
3710 /* 90 */ 39, 39, 40, 40, 41, 41, 42, 42, 43, 43,
3711 /* 100 */ 44, 44, 45, 45, 46, 46, 47, 47, 48, 48,
3712 /* 110 */ 49, 49, 50, 50, 51, 51, 52, 52, 53, 53,
3713 /* 120 */ 54, 54, 55, 55, 56, 56, 57, 57
3714 };
3715
3716 /*
3717 ** Return the length of the data corresponding to the supplied serial-type.
3718 */
sqlite3VdbeSerialTypeLen(u32 serial_type)3719 u32 sqlite3VdbeSerialTypeLen(u32 serial_type){
3720 if( serial_type>=128 ){
3721 return (serial_type-12)/2;
3722 }else{
3723 assert( serial_type<12
3724 || sqlite3SmallTypeSizes[serial_type]==(serial_type - 12)/2 );
3725 return sqlite3SmallTypeSizes[serial_type];
3726 }
3727 }
sqlite3VdbeOneByteSerialTypeLen(u8 serial_type)3728 u8 sqlite3VdbeOneByteSerialTypeLen(u8 serial_type){
3729 assert( serial_type<128 );
3730 return sqlite3SmallTypeSizes[serial_type];
3731 }
3732
3733 /*
3734 ** If we are on an architecture with mixed-endian floating
3735 ** points (ex: ARM7) then swap the lower 4 bytes with the
3736 ** upper 4 bytes. Return the result.
3737 **
3738 ** For most architectures, this is a no-op.
3739 **
3740 ** (later): It is reported to me that the mixed-endian problem
3741 ** on ARM7 is an issue with GCC, not with the ARM7 chip. It seems
3742 ** that early versions of GCC stored the two words of a 64-bit
3743 ** float in the wrong order. And that error has been propagated
3744 ** ever since. The blame is not necessarily with GCC, though.
3745 ** GCC might have just copying the problem from a prior compiler.
3746 ** I am also told that newer versions of GCC that follow a different
3747 ** ABI get the byte order right.
3748 **
3749 ** Developers using SQLite on an ARM7 should compile and run their
3750 ** application using -DSQLITE_DEBUG=1 at least once. With DEBUG
3751 ** enabled, some asserts below will ensure that the byte order of
3752 ** floating point values is correct.
3753 **
3754 ** (2007-08-30) Frank van Vugt has studied this problem closely
3755 ** and has send his findings to the SQLite developers. Frank
3756 ** writes that some Linux kernels offer floating point hardware
3757 ** emulation that uses only 32-bit mantissas instead of a full
3758 ** 48-bits as required by the IEEE standard. (This is the
3759 ** CONFIG_FPE_FASTFPE option.) On such systems, floating point
3760 ** byte swapping becomes very complicated. To avoid problems,
3761 ** the necessary byte swapping is carried out using a 64-bit integer
3762 ** rather than a 64-bit float. Frank assures us that the code here
3763 ** works for him. We, the developers, have no way to independently
3764 ** verify this, but Frank seems to know what he is talking about
3765 ** so we trust him.
3766 */
3767 #ifdef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
floatSwap(u64 in)3768 static u64 floatSwap(u64 in){
3769 union {
3770 u64 r;
3771 u32 i[2];
3772 } u;
3773 u32 t;
3774
3775 u.r = in;
3776 t = u.i[0];
3777 u.i[0] = u.i[1];
3778 u.i[1] = t;
3779 return u.r;
3780 }
3781 # define swapMixedEndianFloat(X) X = floatSwap(X)
3782 #else
3783 # define swapMixedEndianFloat(X)
3784 #endif
3785
3786 /*
3787 ** Write the serialized data blob for the value stored in pMem into
3788 ** buf. It is assumed that the caller has allocated sufficient space.
3789 ** Return the number of bytes written.
3790 **
3791 ** nBuf is the amount of space left in buf[]. The caller is responsible
3792 ** for allocating enough space to buf[] to hold the entire field, exclusive
3793 ** of the pMem->u.nZero bytes for a MEM_Zero value.
3794 **
3795 ** Return the number of bytes actually written into buf[]. The number
3796 ** of bytes in the zero-filled tail is included in the return value only
3797 ** if those bytes were zeroed in buf[].
3798 */
sqlite3VdbeSerialPut(u8 * buf,Mem * pMem,u32 serial_type)3799 u32 sqlite3VdbeSerialPut(u8 *buf, Mem *pMem, u32 serial_type){
3800 u32 len;
3801
3802 /* Integer and Real */
3803 if( serial_type<=7 && serial_type>0 ){
3804 u64 v;
3805 u32 i;
3806 if( serial_type==7 ){
3807 assert( sizeof(v)==sizeof(pMem->u.r) );
3808 memcpy(&v, &pMem->u.r, sizeof(v));
3809 swapMixedEndianFloat(v);
3810 }else{
3811 v = pMem->u.i;
3812 }
3813 len = i = sqlite3SmallTypeSizes[serial_type];
3814 assert( i>0 );
3815 do{
3816 buf[--i] = (u8)(v&0xFF);
3817 v >>= 8;
3818 }while( i );
3819 return len;
3820 }
3821
3822 /* String or blob */
3823 if( serial_type>=12 ){
3824 assert( pMem->n + ((pMem->flags & MEM_Zero)?pMem->u.nZero:0)
3825 == (int)sqlite3VdbeSerialTypeLen(serial_type) );
3826 len = pMem->n;
3827 if( len>0 ) memcpy(buf, pMem->z, len);
3828 return len;
3829 }
3830
3831 /* NULL or constants 0 or 1 */
3832 return 0;
3833 }
3834
3835 /* Input "x" is a sequence of unsigned characters that represent a
3836 ** big-endian integer. Return the equivalent native integer
3837 */
3838 #define ONE_BYTE_INT(x) ((i8)(x)[0])
3839 #define TWO_BYTE_INT(x) (256*(i8)((x)[0])|(x)[1])
3840 #define THREE_BYTE_INT(x) (65536*(i8)((x)[0])|((x)[1]<<8)|(x)[2])
3841 #define FOUR_BYTE_UINT(x) (((u32)(x)[0]<<24)|((x)[1]<<16)|((x)[2]<<8)|(x)[3])
3842 #define FOUR_BYTE_INT(x) (16777216*(i8)((x)[0])|((x)[1]<<16)|((x)[2]<<8)|(x)[3])
3843
3844 /*
3845 ** Deserialize the data blob pointed to by buf as serial type serial_type
3846 ** and store the result in pMem. Return the number of bytes read.
3847 **
3848 ** This function is implemented as two separate routines for performance.
3849 ** The few cases that require local variables are broken out into a separate
3850 ** routine so that in most cases the overhead of moving the stack pointer
3851 ** is avoided.
3852 */
serialGet(const unsigned char * buf,u32 serial_type,Mem * pMem)3853 static u32 serialGet(
3854 const unsigned char *buf, /* Buffer to deserialize from */
3855 u32 serial_type, /* Serial type to deserialize */
3856 Mem *pMem /* Memory cell to write value into */
3857 ){
3858 u64 x = FOUR_BYTE_UINT(buf);
3859 u32 y = FOUR_BYTE_UINT(buf+4);
3860 x = (x<<32) + y;
3861 if( serial_type==6 ){
3862 /* EVIDENCE-OF: R-29851-52272 Value is a big-endian 64-bit
3863 ** twos-complement integer. */
3864 pMem->u.i = *(i64*)&x;
3865 pMem->flags = MEM_Int;
3866 testcase( pMem->u.i<0 );
3867 }else{
3868 /* EVIDENCE-OF: R-57343-49114 Value is a big-endian IEEE 754-2008 64-bit
3869 ** floating point number. */
3870 #if !defined(NDEBUG) && !defined(SQLITE_OMIT_FLOATING_POINT)
3871 /* Verify that integers and floating point values use the same
3872 ** byte order. Or, that if SQLITE_MIXED_ENDIAN_64BIT_FLOAT is
3873 ** defined that 64-bit floating point values really are mixed
3874 ** endian.
3875 */
3876 static const u64 t1 = ((u64)0x3ff00000)<<32;
3877 static const double r1 = 1.0;
3878 u64 t2 = t1;
3879 swapMixedEndianFloat(t2);
3880 assert( sizeof(r1)==sizeof(t2) && memcmp(&r1, &t2, sizeof(r1))==0 );
3881 #endif
3882 assert( sizeof(x)==8 && sizeof(pMem->u.r)==8 );
3883 swapMixedEndianFloat(x);
3884 memcpy(&pMem->u.r, &x, sizeof(x));
3885 pMem->flags = IsNaN(x) ? MEM_Null : MEM_Real;
3886 }
3887 return 8;
3888 }
sqlite3VdbeSerialGet(const unsigned char * buf,u32 serial_type,Mem * pMem)3889 u32 sqlite3VdbeSerialGet(
3890 const unsigned char *buf, /* Buffer to deserialize from */
3891 u32 serial_type, /* Serial type to deserialize */
3892 Mem *pMem /* Memory cell to write value into */
3893 ){
3894 switch( serial_type ){
3895 case 10: { /* Internal use only: NULL with virtual table
3896 ** UPDATE no-change flag set */
3897 pMem->flags = MEM_Null|MEM_Zero;
3898 pMem->n = 0;
3899 pMem->u.nZero = 0;
3900 break;
3901 }
3902 case 11: /* Reserved for future use */
3903 case 0: { /* Null */
3904 /* EVIDENCE-OF: R-24078-09375 Value is a NULL. */
3905 pMem->flags = MEM_Null;
3906 break;
3907 }
3908 case 1: {
3909 /* EVIDENCE-OF: R-44885-25196 Value is an 8-bit twos-complement
3910 ** integer. */
3911 pMem->u.i = ONE_BYTE_INT(buf);
3912 pMem->flags = MEM_Int;
3913 testcase( pMem->u.i<0 );
3914 return 1;
3915 }
3916 case 2: { /* 2-byte signed integer */
3917 /* EVIDENCE-OF: R-49794-35026 Value is a big-endian 16-bit
3918 ** twos-complement integer. */
3919 pMem->u.i = TWO_BYTE_INT(buf);
3920 pMem->flags = MEM_Int;
3921 testcase( pMem->u.i<0 );
3922 return 2;
3923 }
3924 case 3: { /* 3-byte signed integer */
3925 /* EVIDENCE-OF: R-37839-54301 Value is a big-endian 24-bit
3926 ** twos-complement integer. */
3927 pMem->u.i = THREE_BYTE_INT(buf);
3928 pMem->flags = MEM_Int;
3929 testcase( pMem->u.i<0 );
3930 return 3;
3931 }
3932 case 4: { /* 4-byte signed integer */
3933 /* EVIDENCE-OF: R-01849-26079 Value is a big-endian 32-bit
3934 ** twos-complement integer. */
3935 pMem->u.i = FOUR_BYTE_INT(buf);
3936 #ifdef __HP_cc
3937 /* Work around a sign-extension bug in the HP compiler for HP/UX */
3938 if( buf[0]&0x80 ) pMem->u.i |= 0xffffffff80000000LL;
3939 #endif
3940 pMem->flags = MEM_Int;
3941 testcase( pMem->u.i<0 );
3942 return 4;
3943 }
3944 case 5: { /* 6-byte signed integer */
3945 /* EVIDENCE-OF: R-50385-09674 Value is a big-endian 48-bit
3946 ** twos-complement integer. */
3947 pMem->u.i = FOUR_BYTE_UINT(buf+2) + (((i64)1)<<32)*TWO_BYTE_INT(buf);
3948 pMem->flags = MEM_Int;
3949 testcase( pMem->u.i<0 );
3950 return 6;
3951 }
3952 case 6: /* 8-byte signed integer */
3953 case 7: { /* IEEE floating point */
3954 /* These use local variables, so do them in a separate routine
3955 ** to avoid having to move the frame pointer in the common case */
3956 return serialGet(buf,serial_type,pMem);
3957 }
3958 case 8: /* Integer 0 */
3959 case 9: { /* Integer 1 */
3960 /* EVIDENCE-OF: R-12976-22893 Value is the integer 0. */
3961 /* EVIDENCE-OF: R-18143-12121 Value is the integer 1. */
3962 pMem->u.i = serial_type-8;
3963 pMem->flags = MEM_Int;
3964 return 0;
3965 }
3966 default: {
3967 /* EVIDENCE-OF: R-14606-31564 Value is a BLOB that is (N-12)/2 bytes in
3968 ** length.
3969 ** EVIDENCE-OF: R-28401-00140 Value is a string in the text encoding and
3970 ** (N-13)/2 bytes in length. */
3971 static const u16 aFlag[] = { MEM_Blob|MEM_Ephem, MEM_Str|MEM_Ephem };
3972 pMem->z = (char *)buf;
3973 pMem->n = (serial_type-12)/2;
3974 pMem->flags = aFlag[serial_type&1];
3975 return pMem->n;
3976 }
3977 }
3978 return 0;
3979 }
3980 /*
3981 ** This routine is used to allocate sufficient space for an UnpackedRecord
3982 ** structure large enough to be used with sqlite3VdbeRecordUnpack() if
3983 ** the first argument is a pointer to KeyInfo structure pKeyInfo.
3984 **
3985 ** The space is either allocated using sqlite3DbMallocRaw() or from within
3986 ** the unaligned buffer passed via the second and third arguments (presumably
3987 ** stack space). If the former, then *ppFree is set to a pointer that should
3988 ** be eventually freed by the caller using sqlite3DbFree(). Or, if the
3989 ** allocation comes from the pSpace/szSpace buffer, *ppFree is set to NULL
3990 ** before returning.
3991 **
3992 ** If an OOM error occurs, NULL is returned.
3993 */
sqlite3VdbeAllocUnpackedRecord(KeyInfo * pKeyInfo)3994 UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(
3995 KeyInfo *pKeyInfo /* Description of the record */
3996 ){
3997 UnpackedRecord *p; /* Unpacked record to return */
3998 int nByte; /* Number of bytes required for *p */
3999 nByte = ROUND8(sizeof(UnpackedRecord)) + sizeof(Mem)*(pKeyInfo->nKeyField+1);
4000 p = (UnpackedRecord *)sqlite3DbMallocRaw(pKeyInfo->db, nByte);
4001 if( !p ) return 0;
4002 p->aMem = (Mem*)&((char*)p)[ROUND8(sizeof(UnpackedRecord))];
4003 assert( pKeyInfo->aSortFlags!=0 );
4004 p->pKeyInfo = pKeyInfo;
4005 p->nField = pKeyInfo->nKeyField + 1;
4006 return p;
4007 }
4008
4009 /*
4010 ** Given the nKey-byte encoding of a record in pKey[], populate the
4011 ** UnpackedRecord structure indicated by the fourth argument with the
4012 ** contents of the decoded record.
4013 */
sqlite3VdbeRecordUnpack(KeyInfo * pKeyInfo,int nKey,const void * pKey,UnpackedRecord * p)4014 void sqlite3VdbeRecordUnpack(
4015 KeyInfo *pKeyInfo, /* Information about the record format */
4016 int nKey, /* Size of the binary record */
4017 const void *pKey, /* The binary record */
4018 UnpackedRecord *p /* Populate this structure before returning. */
4019 ){
4020 const unsigned char *aKey = (const unsigned char *)pKey;
4021 u32 d;
4022 u32 idx; /* Offset in aKey[] to read from */
4023 u16 u; /* Unsigned loop counter */
4024 u32 szHdr;
4025 Mem *pMem = p->aMem;
4026
4027 p->default_rc = 0;
4028 assert( EIGHT_BYTE_ALIGNMENT(pMem) );
4029 idx = getVarint32(aKey, szHdr);
4030 d = szHdr;
4031 u = 0;
4032 while( idx<szHdr && d<=(u32)nKey ){
4033 u32 serial_type;
4034
4035 idx += getVarint32(&aKey[idx], serial_type);
4036 pMem->enc = pKeyInfo->enc;
4037 pMem->db = pKeyInfo->db;
4038 /* pMem->flags = 0; // sqlite3VdbeSerialGet() will set this for us */
4039 pMem->szMalloc = 0;
4040 pMem->z = 0;
4041 d += sqlite3VdbeSerialGet(&aKey[d], serial_type, pMem);
4042 pMem++;
4043 if( (++u)>=p->nField ) break;
4044 }
4045 if( d>(u32)nKey && u ){
4046 assert( CORRUPT_DB );
4047 /* In a corrupt record entry, the last pMem might have been set up using
4048 ** uninitialized memory. Overwrite its value with NULL, to prevent
4049 ** warnings from MSAN. */
4050 sqlite3VdbeMemSetNull(pMem-1);
4051 }
4052 assert( u<=pKeyInfo->nKeyField + 1 );
4053 p->nField = u;
4054 }
4055
4056 #ifdef SQLITE_DEBUG
4057 /*
4058 ** This function compares two index or table record keys in the same way
4059 ** as the sqlite3VdbeRecordCompare() routine. Unlike VdbeRecordCompare(),
4060 ** this function deserializes and compares values using the
4061 ** sqlite3VdbeSerialGet() and sqlite3MemCompare() functions. It is used
4062 ** in assert() statements to ensure that the optimized code in
4063 ** sqlite3VdbeRecordCompare() returns results with these two primitives.
4064 **
4065 ** Return true if the result of comparison is equivalent to desiredResult.
4066 ** Return false if there is a disagreement.
4067 */
vdbeRecordCompareDebug(int nKey1,const void * pKey1,const UnpackedRecord * pPKey2,int desiredResult)4068 static int vdbeRecordCompareDebug(
4069 int nKey1, const void *pKey1, /* Left key */
4070 const UnpackedRecord *pPKey2, /* Right key */
4071 int desiredResult /* Correct answer */
4072 ){
4073 u32 d1; /* Offset into aKey[] of next data element */
4074 u32 idx1; /* Offset into aKey[] of next header element */
4075 u32 szHdr1; /* Number of bytes in header */
4076 int i = 0;
4077 int rc = 0;
4078 const unsigned char *aKey1 = (const unsigned char *)pKey1;
4079 KeyInfo *pKeyInfo;
4080 Mem mem1;
4081
4082 pKeyInfo = pPKey2->pKeyInfo;
4083 if( pKeyInfo->db==0 ) return 1;
4084 mem1.enc = pKeyInfo->enc;
4085 mem1.db = pKeyInfo->db;
4086 /* mem1.flags = 0; // Will be initialized by sqlite3VdbeSerialGet() */
4087 VVA_ONLY( mem1.szMalloc = 0; ) /* Only needed by assert() statements */
4088
4089 /* Compilers may complain that mem1.u.i is potentially uninitialized.
4090 ** We could initialize it, as shown here, to silence those complaints.
4091 ** But in fact, mem1.u.i will never actually be used uninitialized, and doing
4092 ** the unnecessary initialization has a measurable negative performance
4093 ** impact, since this routine is a very high runner. And so, we choose
4094 ** to ignore the compiler warnings and leave this variable uninitialized.
4095 */
4096 /* mem1.u.i = 0; // not needed, here to silence compiler warning */
4097
4098 idx1 = getVarint32(aKey1, szHdr1);
4099 if( szHdr1>98307 ) return SQLITE_CORRUPT;
4100 d1 = szHdr1;
4101 assert( pKeyInfo->nAllField>=pPKey2->nField || CORRUPT_DB );
4102 assert( pKeyInfo->aSortFlags!=0 );
4103 assert( pKeyInfo->nKeyField>0 );
4104 assert( idx1<=szHdr1 || CORRUPT_DB );
4105 do{
4106 u32 serial_type1;
4107
4108 /* Read the serial types for the next element in each key. */
4109 idx1 += getVarint32( aKey1+idx1, serial_type1 );
4110
4111 /* Verify that there is enough key space remaining to avoid
4112 ** a buffer overread. The "d1+serial_type1+2" subexpression will
4113 ** always be greater than or equal to the amount of required key space.
4114 ** Use that approximation to avoid the more expensive call to
4115 ** sqlite3VdbeSerialTypeLen() in the common case.
4116 */
4117 if( d1+(u64)serial_type1+2>(u64)nKey1
4118 && d1+(u64)sqlite3VdbeSerialTypeLen(serial_type1)>(u64)nKey1
4119 ){
4120 break;
4121 }
4122
4123 /* Extract the values to be compared.
4124 */
4125 d1 += sqlite3VdbeSerialGet(&aKey1[d1], serial_type1, &mem1);
4126
4127 /* Do the comparison
4128 */
4129 rc = sqlite3MemCompare(&mem1, &pPKey2->aMem[i],
4130 pKeyInfo->nAllField>i ? pKeyInfo->aColl[i] : 0);
4131 if( rc!=0 ){
4132 assert( mem1.szMalloc==0 ); /* See comment below */
4133 if( (pKeyInfo->aSortFlags[i] & KEYINFO_ORDER_BIGNULL)
4134 && ((mem1.flags & MEM_Null) || (pPKey2->aMem[i].flags & MEM_Null))
4135 ){
4136 rc = -rc;
4137 }
4138 if( pKeyInfo->aSortFlags[i] & KEYINFO_ORDER_DESC ){
4139 rc = -rc; /* Invert the result for DESC sort order. */
4140 }
4141 goto debugCompareEnd;
4142 }
4143 i++;
4144 }while( idx1<szHdr1 && i<pPKey2->nField );
4145
4146 /* No memory allocation is ever used on mem1. Prove this using
4147 ** the following assert(). If the assert() fails, it indicates a
4148 ** memory leak and a need to call sqlite3VdbeMemRelease(&mem1).
4149 */
4150 assert( mem1.szMalloc==0 );
4151
4152 /* rc==0 here means that one of the keys ran out of fields and
4153 ** all the fields up to that point were equal. Return the default_rc
4154 ** value. */
4155 rc = pPKey2->default_rc;
4156
4157 debugCompareEnd:
4158 if( desiredResult==0 && rc==0 ) return 1;
4159 if( desiredResult<0 && rc<0 ) return 1;
4160 if( desiredResult>0 && rc>0 ) return 1;
4161 if( CORRUPT_DB ) return 1;
4162 if( pKeyInfo->db->mallocFailed ) return 1;
4163 return 0;
4164 }
4165 #endif
4166
4167 #ifdef SQLITE_DEBUG
4168 /*
4169 ** Count the number of fields (a.k.a. columns) in the record given by
4170 ** pKey,nKey. The verify that this count is less than or equal to the
4171 ** limit given by pKeyInfo->nAllField.
4172 **
4173 ** If this constraint is not satisfied, it means that the high-speed
4174 ** vdbeRecordCompareInt() and vdbeRecordCompareString() routines will
4175 ** not work correctly. If this assert() ever fires, it probably means
4176 ** that the KeyInfo.nKeyField or KeyInfo.nAllField values were computed
4177 ** incorrectly.
4178 */
vdbeAssertFieldCountWithinLimits(int nKey,const void * pKey,const KeyInfo * pKeyInfo)4179 static void vdbeAssertFieldCountWithinLimits(
4180 int nKey, const void *pKey, /* The record to verify */
4181 const KeyInfo *pKeyInfo /* Compare size with this KeyInfo */
4182 ){
4183 int nField = 0;
4184 u32 szHdr;
4185 u32 idx;
4186 u32 notUsed;
4187 const unsigned char *aKey = (const unsigned char*)pKey;
4188
4189 if( CORRUPT_DB ) return;
4190 idx = getVarint32(aKey, szHdr);
4191 assert( nKey>=0 );
4192 assert( szHdr<=(u32)nKey );
4193 while( idx<szHdr ){
4194 idx += getVarint32(aKey+idx, notUsed);
4195 nField++;
4196 }
4197 assert( nField <= pKeyInfo->nAllField );
4198 }
4199 #else
4200 # define vdbeAssertFieldCountWithinLimits(A,B,C)
4201 #endif
4202
4203 /*
4204 ** Both *pMem1 and *pMem2 contain string values. Compare the two values
4205 ** using the collation sequence pColl. As usual, return a negative , zero
4206 ** or positive value if *pMem1 is less than, equal to or greater than
4207 ** *pMem2, respectively. Similar in spirit to "rc = (*pMem1) - (*pMem2);".
4208 */
vdbeCompareMemString(const Mem * pMem1,const Mem * pMem2,const CollSeq * pColl,u8 * prcErr)4209 static int vdbeCompareMemString(
4210 const Mem *pMem1,
4211 const Mem *pMem2,
4212 const CollSeq *pColl,
4213 u8 *prcErr /* If an OOM occurs, set to SQLITE_NOMEM */
4214 ){
4215 if( pMem1->enc==pColl->enc ){
4216 /* The strings are already in the correct encoding. Call the
4217 ** comparison function directly */
4218 return pColl->xCmp(pColl->pUser,pMem1->n,pMem1->z,pMem2->n,pMem2->z);
4219 }else{
4220 int rc;
4221 const void *v1, *v2;
4222 Mem c1;
4223 Mem c2;
4224 sqlite3VdbeMemInit(&c1, pMem1->db, MEM_Null);
4225 sqlite3VdbeMemInit(&c2, pMem1->db, MEM_Null);
4226 sqlite3VdbeMemShallowCopy(&c1, pMem1, MEM_Ephem);
4227 sqlite3VdbeMemShallowCopy(&c2, pMem2, MEM_Ephem);
4228 v1 = sqlite3ValueText((sqlite3_value*)&c1, pColl->enc);
4229 v2 = sqlite3ValueText((sqlite3_value*)&c2, pColl->enc);
4230 if( (v1==0 || v2==0) ){
4231 if( prcErr ) *prcErr = SQLITE_NOMEM_BKPT;
4232 rc = 0;
4233 }else{
4234 rc = pColl->xCmp(pColl->pUser, c1.n, v1, c2.n, v2);
4235 }
4236 sqlite3VdbeMemRelease(&c1);
4237 sqlite3VdbeMemRelease(&c2);
4238 return rc;
4239 }
4240 }
4241
4242 /*
4243 ** The input pBlob is guaranteed to be a Blob that is not marked
4244 ** with MEM_Zero. Return true if it could be a zero-blob.
4245 */
isAllZero(const char * z,int n)4246 static int isAllZero(const char *z, int n){
4247 int i;
4248 for(i=0; i<n; i++){
4249 if( z[i] ) return 0;
4250 }
4251 return 1;
4252 }
4253
4254 /*
4255 ** Compare two blobs. Return negative, zero, or positive if the first
4256 ** is less than, equal to, or greater than the second, respectively.
4257 ** If one blob is a prefix of the other, then the shorter is the lessor.
4258 */
sqlite3BlobCompare(const Mem * pB1,const Mem * pB2)4259 SQLITE_NOINLINE int sqlite3BlobCompare(const Mem *pB1, const Mem *pB2){
4260 int c;
4261 int n1 = pB1->n;
4262 int n2 = pB2->n;
4263
4264 /* It is possible to have a Blob value that has some non-zero content
4265 ** followed by zero content. But that only comes up for Blobs formed
4266 ** by the OP_MakeRecord opcode, and such Blobs never get passed into
4267 ** sqlite3MemCompare(). */
4268 assert( (pB1->flags & MEM_Zero)==0 || n1==0 );
4269 assert( (pB2->flags & MEM_Zero)==0 || n2==0 );
4270
4271 if( (pB1->flags|pB2->flags) & MEM_Zero ){
4272 if( pB1->flags & pB2->flags & MEM_Zero ){
4273 return pB1->u.nZero - pB2->u.nZero;
4274 }else if( pB1->flags & MEM_Zero ){
4275 if( !isAllZero(pB2->z, pB2->n) ) return -1;
4276 return pB1->u.nZero - n2;
4277 }else{
4278 if( !isAllZero(pB1->z, pB1->n) ) return +1;
4279 return n1 - pB2->u.nZero;
4280 }
4281 }
4282 c = memcmp(pB1->z, pB2->z, n1>n2 ? n2 : n1);
4283 if( c ) return c;
4284 return n1 - n2;
4285 }
4286
4287 /*
4288 ** Do a comparison between a 64-bit signed integer and a 64-bit floating-point
4289 ** number. Return negative, zero, or positive if the first (i64) is less than,
4290 ** equal to, or greater than the second (double).
4291 */
sqlite3IntFloatCompare(i64 i,double r)4292 static int sqlite3IntFloatCompare(i64 i, double r){
4293 if( sizeof(LONGDOUBLE_TYPE)>8 ){
4294 LONGDOUBLE_TYPE x = (LONGDOUBLE_TYPE)i;
4295 testcase( x<r );
4296 testcase( x>r );
4297 testcase( x==r );
4298 if( x<r ) return -1;
4299 if( x>r ) return +1; /*NO_TEST*/ /* work around bugs in gcov */
4300 return 0; /*NO_TEST*/ /* work around bugs in gcov */
4301 }else{
4302 i64 y;
4303 double s;
4304 if( r<-9223372036854775808.0 ) return +1;
4305 if( r>=9223372036854775808.0 ) return -1;
4306 y = (i64)r;
4307 if( i<y ) return -1;
4308 if( i>y ) return +1;
4309 s = (double)i;
4310 if( s<r ) return -1;
4311 if( s>r ) return +1;
4312 return 0;
4313 }
4314 }
4315
4316 /*
4317 ** Compare the values contained by the two memory cells, returning
4318 ** negative, zero or positive if pMem1 is less than, equal to, or greater
4319 ** than pMem2. Sorting order is NULL's first, followed by numbers (integers
4320 ** and reals) sorted numerically, followed by text ordered by the collating
4321 ** sequence pColl and finally blob's ordered by memcmp().
4322 **
4323 ** Two NULL values are considered equal by this function.
4324 */
sqlite3MemCompare(const Mem * pMem1,const Mem * pMem2,const CollSeq * pColl)4325 int sqlite3MemCompare(const Mem *pMem1, const Mem *pMem2, const CollSeq *pColl){
4326 int f1, f2;
4327 int combined_flags;
4328
4329 f1 = pMem1->flags;
4330 f2 = pMem2->flags;
4331 combined_flags = f1|f2;
4332 assert( !sqlite3VdbeMemIsRowSet(pMem1) && !sqlite3VdbeMemIsRowSet(pMem2) );
4333
4334 /* If one value is NULL, it is less than the other. If both values
4335 ** are NULL, return 0.
4336 */
4337 if( combined_flags&MEM_Null ){
4338 return (f2&MEM_Null) - (f1&MEM_Null);
4339 }
4340
4341 /* At least one of the two values is a number
4342 */
4343 if( combined_flags&(MEM_Int|MEM_Real|MEM_IntReal) ){
4344 testcase( combined_flags & MEM_Int );
4345 testcase( combined_flags & MEM_Real );
4346 testcase( combined_flags & MEM_IntReal );
4347 if( (f1 & f2 & (MEM_Int|MEM_IntReal))!=0 ){
4348 testcase( f1 & f2 & MEM_Int );
4349 testcase( f1 & f2 & MEM_IntReal );
4350 if( pMem1->u.i < pMem2->u.i ) return -1;
4351 if( pMem1->u.i > pMem2->u.i ) return +1;
4352 return 0;
4353 }
4354 if( (f1 & f2 & MEM_Real)!=0 ){
4355 if( pMem1->u.r < pMem2->u.r ) return -1;
4356 if( pMem1->u.r > pMem2->u.r ) return +1;
4357 return 0;
4358 }
4359 if( (f1&(MEM_Int|MEM_IntReal))!=0 ){
4360 testcase( f1 & MEM_Int );
4361 testcase( f1 & MEM_IntReal );
4362 if( (f2&MEM_Real)!=0 ){
4363 return sqlite3IntFloatCompare(pMem1->u.i, pMem2->u.r);
4364 }else if( (f2&(MEM_Int|MEM_IntReal))!=0 ){
4365 if( pMem1->u.i < pMem2->u.i ) return -1;
4366 if( pMem1->u.i > pMem2->u.i ) return +1;
4367 return 0;
4368 }else{
4369 return -1;
4370 }
4371 }
4372 if( (f1&MEM_Real)!=0 ){
4373 if( (f2&(MEM_Int|MEM_IntReal))!=0 ){
4374 testcase( f2 & MEM_Int );
4375 testcase( f2 & MEM_IntReal );
4376 return -sqlite3IntFloatCompare(pMem2->u.i, pMem1->u.r);
4377 }else{
4378 return -1;
4379 }
4380 }
4381 return +1;
4382 }
4383
4384 /* If one value is a string and the other is a blob, the string is less.
4385 ** If both are strings, compare using the collating functions.
4386 */
4387 if( combined_flags&MEM_Str ){
4388 if( (f1 & MEM_Str)==0 ){
4389 return 1;
4390 }
4391 if( (f2 & MEM_Str)==0 ){
4392 return -1;
4393 }
4394
4395 assert( pMem1->enc==pMem2->enc || pMem1->db->mallocFailed );
4396 assert( pMem1->enc==SQLITE_UTF8 ||
4397 pMem1->enc==SQLITE_UTF16LE || pMem1->enc==SQLITE_UTF16BE );
4398
4399 /* The collation sequence must be defined at this point, even if
4400 ** the user deletes the collation sequence after the vdbe program is
4401 ** compiled (this was not always the case).
4402 */
4403 assert( !pColl || pColl->xCmp );
4404
4405 if( pColl ){
4406 return vdbeCompareMemString(pMem1, pMem2, pColl, 0);
4407 }
4408 /* If a NULL pointer was passed as the collate function, fall through
4409 ** to the blob case and use memcmp(). */
4410 }
4411
4412 /* Both values must be blobs. Compare using memcmp(). */
4413 return sqlite3BlobCompare(pMem1, pMem2);
4414 }
4415
4416
4417 /*
4418 ** The first argument passed to this function is a serial-type that
4419 ** corresponds to an integer - all values between 1 and 9 inclusive
4420 ** except 7. The second points to a buffer containing an integer value
4421 ** serialized according to serial_type. This function deserializes
4422 ** and returns the value.
4423 */
vdbeRecordDecodeInt(u32 serial_type,const u8 * aKey)4424 static i64 vdbeRecordDecodeInt(u32 serial_type, const u8 *aKey){
4425 u32 y;
4426 assert( CORRUPT_DB || (serial_type>=1 && serial_type<=9 && serial_type!=7) );
4427 switch( serial_type ){
4428 case 0:
4429 case 1:
4430 testcase( aKey[0]&0x80 );
4431 return ONE_BYTE_INT(aKey);
4432 case 2:
4433 testcase( aKey[0]&0x80 );
4434 return TWO_BYTE_INT(aKey);
4435 case 3:
4436 testcase( aKey[0]&0x80 );
4437 return THREE_BYTE_INT(aKey);
4438 case 4: {
4439 testcase( aKey[0]&0x80 );
4440 y = FOUR_BYTE_UINT(aKey);
4441 return (i64)*(int*)&y;
4442 }
4443 case 5: {
4444 testcase( aKey[0]&0x80 );
4445 return FOUR_BYTE_UINT(aKey+2) + (((i64)1)<<32)*TWO_BYTE_INT(aKey);
4446 }
4447 case 6: {
4448 u64 x = FOUR_BYTE_UINT(aKey);
4449 testcase( aKey[0]&0x80 );
4450 x = (x<<32) | FOUR_BYTE_UINT(aKey+4);
4451 return (i64)*(i64*)&x;
4452 }
4453 }
4454
4455 return (serial_type - 8);
4456 }
4457
4458 /*
4459 ** This function compares the two table rows or index records
4460 ** specified by {nKey1, pKey1} and pPKey2. It returns a negative, zero
4461 ** or positive integer if key1 is less than, equal to or
4462 ** greater than key2. The {nKey1, pKey1} key must be a blob
4463 ** created by the OP_MakeRecord opcode of the VDBE. The pPKey2
4464 ** key must be a parsed key such as obtained from
4465 ** sqlite3VdbeParseRecord.
4466 **
4467 ** If argument bSkip is non-zero, it is assumed that the caller has already
4468 ** determined that the first fields of the keys are equal.
4469 **
4470 ** Key1 and Key2 do not have to contain the same number of fields. If all
4471 ** fields that appear in both keys are equal, then pPKey2->default_rc is
4472 ** returned.
4473 **
4474 ** If database corruption is discovered, set pPKey2->errCode to
4475 ** SQLITE_CORRUPT and return 0. If an OOM error is encountered,
4476 ** pPKey2->errCode is set to SQLITE_NOMEM and, if it is not NULL, the
4477 ** malloc-failed flag set on database handle (pPKey2->pKeyInfo->db).
4478 */
sqlite3VdbeRecordCompareWithSkip(int nKey1,const void * pKey1,UnpackedRecord * pPKey2,int bSkip)4479 int sqlite3VdbeRecordCompareWithSkip(
4480 int nKey1, const void *pKey1, /* Left key */
4481 UnpackedRecord *pPKey2, /* Right key */
4482 int bSkip /* If true, skip the first field */
4483 ){
4484 u32 d1; /* Offset into aKey[] of next data element */
4485 int i; /* Index of next field to compare */
4486 u32 szHdr1; /* Size of record header in bytes */
4487 u32 idx1; /* Offset of first type in header */
4488 int rc = 0; /* Return value */
4489 Mem *pRhs = pPKey2->aMem; /* Next field of pPKey2 to compare */
4490 KeyInfo *pKeyInfo;
4491 const unsigned char *aKey1 = (const unsigned char *)pKey1;
4492 Mem mem1;
4493
4494 /* If bSkip is true, then the caller has already determined that the first
4495 ** two elements in the keys are equal. Fix the various stack variables so
4496 ** that this routine begins comparing at the second field. */
4497 if( bSkip ){
4498 u32 s1;
4499 idx1 = 1 + getVarint32(&aKey1[1], s1);
4500 szHdr1 = aKey1[0];
4501 d1 = szHdr1 + sqlite3VdbeSerialTypeLen(s1);
4502 i = 1;
4503 pRhs++;
4504 }else{
4505 idx1 = getVarint32(aKey1, szHdr1);
4506 d1 = szHdr1;
4507 i = 0;
4508 }
4509 if( d1>(unsigned)nKey1 ){
4510 pPKey2->errCode = (u8)SQLITE_CORRUPT_BKPT;
4511 return 0; /* Corruption */
4512 }
4513
4514 VVA_ONLY( mem1.szMalloc = 0; ) /* Only needed by assert() statements */
4515 assert( pPKey2->pKeyInfo->nAllField>=pPKey2->nField
4516 || CORRUPT_DB );
4517 assert( pPKey2->pKeyInfo->aSortFlags!=0 );
4518 assert( pPKey2->pKeyInfo->nKeyField>0 );
4519 assert( idx1<=szHdr1 || CORRUPT_DB );
4520 do{
4521 u32 serial_type;
4522
4523 /* RHS is an integer */
4524 if( pRhs->flags & (MEM_Int|MEM_IntReal) ){
4525 testcase( pRhs->flags & MEM_Int );
4526 testcase( pRhs->flags & MEM_IntReal );
4527 serial_type = aKey1[idx1];
4528 testcase( serial_type==12 );
4529 if( serial_type>=10 ){
4530 rc = +1;
4531 }else if( serial_type==0 ){
4532 rc = -1;
4533 }else if( serial_type==7 ){
4534 sqlite3VdbeSerialGet(&aKey1[d1], serial_type, &mem1);
4535 rc = -sqlite3IntFloatCompare(pRhs->u.i, mem1.u.r);
4536 }else{
4537 i64 lhs = vdbeRecordDecodeInt(serial_type, &aKey1[d1]);
4538 i64 rhs = pRhs->u.i;
4539 if( lhs<rhs ){
4540 rc = -1;
4541 }else if( lhs>rhs ){
4542 rc = +1;
4543 }
4544 }
4545 }
4546
4547 /* RHS is real */
4548 else if( pRhs->flags & MEM_Real ){
4549 serial_type = aKey1[idx1];
4550 if( serial_type>=10 ){
4551 /* Serial types 12 or greater are strings and blobs (greater than
4552 ** numbers). Types 10 and 11 are currently "reserved for future
4553 ** use", so it doesn't really matter what the results of comparing
4554 ** them to numberic values are. */
4555 rc = +1;
4556 }else if( serial_type==0 ){
4557 rc = -1;
4558 }else{
4559 sqlite3VdbeSerialGet(&aKey1[d1], serial_type, &mem1);
4560 if( serial_type==7 ){
4561 if( mem1.u.r<pRhs->u.r ){
4562 rc = -1;
4563 }else if( mem1.u.r>pRhs->u.r ){
4564 rc = +1;
4565 }
4566 }else{
4567 rc = sqlite3IntFloatCompare(mem1.u.i, pRhs->u.r);
4568 }
4569 }
4570 }
4571
4572 /* RHS is a string */
4573 else if( pRhs->flags & MEM_Str ){
4574 getVarint32NR(&aKey1[idx1], serial_type);
4575 testcase( serial_type==12 );
4576 if( serial_type<12 ){
4577 rc = -1;
4578 }else if( !(serial_type & 0x01) ){
4579 rc = +1;
4580 }else{
4581 mem1.n = (serial_type - 12) / 2;
4582 testcase( (d1+mem1.n)==(unsigned)nKey1 );
4583 testcase( (d1+mem1.n+1)==(unsigned)nKey1 );
4584 if( (d1+mem1.n) > (unsigned)nKey1
4585 || (pKeyInfo = pPKey2->pKeyInfo)->nAllField<=i
4586 ){
4587 pPKey2->errCode = (u8)SQLITE_CORRUPT_BKPT;
4588 return 0; /* Corruption */
4589 }else if( pKeyInfo->aColl[i] ){
4590 mem1.enc = pKeyInfo->enc;
4591 mem1.db = pKeyInfo->db;
4592 mem1.flags = MEM_Str;
4593 mem1.z = (char*)&aKey1[d1];
4594 rc = vdbeCompareMemString(
4595 &mem1, pRhs, pKeyInfo->aColl[i], &pPKey2->errCode
4596 );
4597 }else{
4598 int nCmp = MIN(mem1.n, pRhs->n);
4599 rc = memcmp(&aKey1[d1], pRhs->z, nCmp);
4600 if( rc==0 ) rc = mem1.n - pRhs->n;
4601 }
4602 }
4603 }
4604
4605 /* RHS is a blob */
4606 else if( pRhs->flags & MEM_Blob ){
4607 assert( (pRhs->flags & MEM_Zero)==0 || pRhs->n==0 );
4608 getVarint32NR(&aKey1[idx1], serial_type);
4609 testcase( serial_type==12 );
4610 if( serial_type<12 || (serial_type & 0x01) ){
4611 rc = -1;
4612 }else{
4613 int nStr = (serial_type - 12) / 2;
4614 testcase( (d1+nStr)==(unsigned)nKey1 );
4615 testcase( (d1+nStr+1)==(unsigned)nKey1 );
4616 if( (d1+nStr) > (unsigned)nKey1 ){
4617 pPKey2->errCode = (u8)SQLITE_CORRUPT_BKPT;
4618 return 0; /* Corruption */
4619 }else if( pRhs->flags & MEM_Zero ){
4620 if( !isAllZero((const char*)&aKey1[d1],nStr) ){
4621 rc = 1;
4622 }else{
4623 rc = nStr - pRhs->u.nZero;
4624 }
4625 }else{
4626 int nCmp = MIN(nStr, pRhs->n);
4627 rc = memcmp(&aKey1[d1], pRhs->z, nCmp);
4628 if( rc==0 ) rc = nStr - pRhs->n;
4629 }
4630 }
4631 }
4632
4633 /* RHS is null */
4634 else{
4635 serial_type = aKey1[idx1];
4636 rc = (serial_type!=0);
4637 }
4638
4639 if( rc!=0 ){
4640 int sortFlags = pPKey2->pKeyInfo->aSortFlags[i];
4641 if( sortFlags ){
4642 if( (sortFlags & KEYINFO_ORDER_BIGNULL)==0
4643 || ((sortFlags & KEYINFO_ORDER_DESC)
4644 !=(serial_type==0 || (pRhs->flags&MEM_Null)))
4645 ){
4646 rc = -rc;
4647 }
4648 }
4649 assert( vdbeRecordCompareDebug(nKey1, pKey1, pPKey2, rc) );
4650 assert( mem1.szMalloc==0 ); /* See comment below */
4651 return rc;
4652 }
4653
4654 i++;
4655 if( i==pPKey2->nField ) break;
4656 pRhs++;
4657 d1 += sqlite3VdbeSerialTypeLen(serial_type);
4658 idx1 += sqlite3VarintLen(serial_type);
4659 }while( idx1<(unsigned)szHdr1 && d1<=(unsigned)nKey1 );
4660
4661 /* No memory allocation is ever used on mem1. Prove this using
4662 ** the following assert(). If the assert() fails, it indicates a
4663 ** memory leak and a need to call sqlite3VdbeMemRelease(&mem1). */
4664 assert( mem1.szMalloc==0 );
4665
4666 /* rc==0 here means that one or both of the keys ran out of fields and
4667 ** all the fields up to that point were equal. Return the default_rc
4668 ** value. */
4669 assert( CORRUPT_DB
4670 || vdbeRecordCompareDebug(nKey1, pKey1, pPKey2, pPKey2->default_rc)
4671 || pPKey2->pKeyInfo->db->mallocFailed
4672 );
4673 pPKey2->eqSeen = 1;
4674 return pPKey2->default_rc;
4675 }
sqlite3VdbeRecordCompare(int nKey1,const void * pKey1,UnpackedRecord * pPKey2)4676 int sqlite3VdbeRecordCompare(
4677 int nKey1, const void *pKey1, /* Left key */
4678 UnpackedRecord *pPKey2 /* Right key */
4679 ){
4680 return sqlite3VdbeRecordCompareWithSkip(nKey1, pKey1, pPKey2, 0);
4681 }
4682
4683
4684 /*
4685 ** This function is an optimized version of sqlite3VdbeRecordCompare()
4686 ** that (a) the first field of pPKey2 is an integer, and (b) the
4687 ** size-of-header varint at the start of (pKey1/nKey1) fits in a single
4688 ** byte (i.e. is less than 128).
4689 **
4690 ** To avoid concerns about buffer overreads, this routine is only used
4691 ** on schemas where the maximum valid header size is 63 bytes or less.
4692 */
vdbeRecordCompareInt(int nKey1,const void * pKey1,UnpackedRecord * pPKey2)4693 static int vdbeRecordCompareInt(
4694 int nKey1, const void *pKey1, /* Left key */
4695 UnpackedRecord *pPKey2 /* Right key */
4696 ){
4697 const u8 *aKey = &((const u8*)pKey1)[*(const u8*)pKey1 & 0x3F];
4698 int serial_type = ((const u8*)pKey1)[1];
4699 int res;
4700 u32 y;
4701 u64 x;
4702 i64 v;
4703 i64 lhs;
4704
4705 vdbeAssertFieldCountWithinLimits(nKey1, pKey1, pPKey2->pKeyInfo);
4706 assert( (*(u8*)pKey1)<=0x3F || CORRUPT_DB );
4707 switch( serial_type ){
4708 case 1: { /* 1-byte signed integer */
4709 lhs = ONE_BYTE_INT(aKey);
4710 testcase( lhs<0 );
4711 break;
4712 }
4713 case 2: { /* 2-byte signed integer */
4714 lhs = TWO_BYTE_INT(aKey);
4715 testcase( lhs<0 );
4716 break;
4717 }
4718 case 3: { /* 3-byte signed integer */
4719 lhs = THREE_BYTE_INT(aKey);
4720 testcase( lhs<0 );
4721 break;
4722 }
4723 case 4: { /* 4-byte signed integer */
4724 y = FOUR_BYTE_UINT(aKey);
4725 lhs = (i64)*(int*)&y;
4726 testcase( lhs<0 );
4727 break;
4728 }
4729 case 5: { /* 6-byte signed integer */
4730 lhs = FOUR_BYTE_UINT(aKey+2) + (((i64)1)<<32)*TWO_BYTE_INT(aKey);
4731 testcase( lhs<0 );
4732 break;
4733 }
4734 case 6: { /* 8-byte signed integer */
4735 x = FOUR_BYTE_UINT(aKey);
4736 x = (x<<32) | FOUR_BYTE_UINT(aKey+4);
4737 lhs = *(i64*)&x;
4738 testcase( lhs<0 );
4739 break;
4740 }
4741 case 8:
4742 lhs = 0;
4743 break;
4744 case 9:
4745 lhs = 1;
4746 break;
4747
4748 /* This case could be removed without changing the results of running
4749 ** this code. Including it causes gcc to generate a faster switch
4750 ** statement (since the range of switch targets now starts at zero and
4751 ** is contiguous) but does not cause any duplicate code to be generated
4752 ** (as gcc is clever enough to combine the two like cases). Other
4753 ** compilers might be similar. */
4754 case 0: case 7:
4755 return sqlite3VdbeRecordCompare(nKey1, pKey1, pPKey2);
4756
4757 default:
4758 return sqlite3VdbeRecordCompare(nKey1, pKey1, pPKey2);
4759 }
4760
4761 v = pPKey2->aMem[0].u.i;
4762 if( v>lhs ){
4763 res = pPKey2->r1;
4764 }else if( v<lhs ){
4765 res = pPKey2->r2;
4766 }else if( pPKey2->nField>1 ){
4767 /* The first fields of the two keys are equal. Compare the trailing
4768 ** fields. */
4769 res = sqlite3VdbeRecordCompareWithSkip(nKey1, pKey1, pPKey2, 1);
4770 }else{
4771 /* The first fields of the two keys are equal and there are no trailing
4772 ** fields. Return pPKey2->default_rc in this case. */
4773 res = pPKey2->default_rc;
4774 pPKey2->eqSeen = 1;
4775 }
4776
4777 assert( vdbeRecordCompareDebug(nKey1, pKey1, pPKey2, res) );
4778 return res;
4779 }
4780
4781 /*
4782 ** This function is an optimized version of sqlite3VdbeRecordCompare()
4783 ** that (a) the first field of pPKey2 is a string, that (b) the first field
4784 ** uses the collation sequence BINARY and (c) that the size-of-header varint
4785 ** at the start of (pKey1/nKey1) fits in a single byte.
4786 */
vdbeRecordCompareString(int nKey1,const void * pKey1,UnpackedRecord * pPKey2)4787 static int vdbeRecordCompareString(
4788 int nKey1, const void *pKey1, /* Left key */
4789 UnpackedRecord *pPKey2 /* Right key */
4790 ){
4791 const u8 *aKey1 = (const u8*)pKey1;
4792 int serial_type;
4793 int res;
4794
4795 assert( pPKey2->aMem[0].flags & MEM_Str );
4796 vdbeAssertFieldCountWithinLimits(nKey1, pKey1, pPKey2->pKeyInfo);
4797 serial_type = (u8)(aKey1[1]);
4798 if( serial_type >= 0x80 ){
4799 sqlite3GetVarint32(&aKey1[1], (u32*)&serial_type);
4800 }
4801 if( serial_type<12 ){
4802 res = pPKey2->r1; /* (pKey1/nKey1) is a number or a null */
4803 }else if( !(serial_type & 0x01) ){
4804 res = pPKey2->r2; /* (pKey1/nKey1) is a blob */
4805 }else{
4806 int nCmp;
4807 int nStr;
4808 int szHdr = aKey1[0];
4809
4810 nStr = (serial_type-12) / 2;
4811 if( (szHdr + nStr) > nKey1 ){
4812 pPKey2->errCode = (u8)SQLITE_CORRUPT_BKPT;
4813 return 0; /* Corruption */
4814 }
4815 nCmp = MIN( pPKey2->aMem[0].n, nStr );
4816 res = memcmp(&aKey1[szHdr], pPKey2->aMem[0].z, nCmp);
4817
4818 if( res>0 ){
4819 res = pPKey2->r2;
4820 }else if( res<0 ){
4821 res = pPKey2->r1;
4822 }else{
4823 res = nStr - pPKey2->aMem[0].n;
4824 if( res==0 ){
4825 if( pPKey2->nField>1 ){
4826 res = sqlite3VdbeRecordCompareWithSkip(nKey1, pKey1, pPKey2, 1);
4827 }else{
4828 res = pPKey2->default_rc;
4829 pPKey2->eqSeen = 1;
4830 }
4831 }else if( res>0 ){
4832 res = pPKey2->r2;
4833 }else{
4834 res = pPKey2->r1;
4835 }
4836 }
4837 }
4838
4839 assert( vdbeRecordCompareDebug(nKey1, pKey1, pPKey2, res)
4840 || CORRUPT_DB
4841 || pPKey2->pKeyInfo->db->mallocFailed
4842 );
4843 return res;
4844 }
4845
4846 /*
4847 ** Return a pointer to an sqlite3VdbeRecordCompare() compatible function
4848 ** suitable for comparing serialized records to the unpacked record passed
4849 ** as the only argument.
4850 */
sqlite3VdbeFindCompare(UnpackedRecord * p)4851 RecordCompare sqlite3VdbeFindCompare(UnpackedRecord *p){
4852 /* varintRecordCompareInt() and varintRecordCompareString() both assume
4853 ** that the size-of-header varint that occurs at the start of each record
4854 ** fits in a single byte (i.e. is 127 or less). varintRecordCompareInt()
4855 ** also assumes that it is safe to overread a buffer by at least the
4856 ** maximum possible legal header size plus 8 bytes. Because there is
4857 ** guaranteed to be at least 74 (but not 136) bytes of padding following each
4858 ** buffer passed to varintRecordCompareInt() this makes it convenient to
4859 ** limit the size of the header to 64 bytes in cases where the first field
4860 ** is an integer.
4861 **
4862 ** The easiest way to enforce this limit is to consider only records with
4863 ** 13 fields or less. If the first field is an integer, the maximum legal
4864 ** header size is (12*5 + 1 + 1) bytes. */
4865 if( p->pKeyInfo->nAllField<=13 ){
4866 int flags = p->aMem[0].flags;
4867 if( p->pKeyInfo->aSortFlags[0] ){
4868 if( p->pKeyInfo->aSortFlags[0] & KEYINFO_ORDER_BIGNULL ){
4869 return sqlite3VdbeRecordCompare;
4870 }
4871 p->r1 = 1;
4872 p->r2 = -1;
4873 }else{
4874 p->r1 = -1;
4875 p->r2 = 1;
4876 }
4877 if( (flags & MEM_Int) ){
4878 return vdbeRecordCompareInt;
4879 }
4880 testcase( flags & MEM_Real );
4881 testcase( flags & MEM_Null );
4882 testcase( flags & MEM_Blob );
4883 if( (flags & (MEM_Real|MEM_IntReal|MEM_Null|MEM_Blob))==0
4884 && p->pKeyInfo->aColl[0]==0
4885 ){
4886 assert( flags & MEM_Str );
4887 return vdbeRecordCompareString;
4888 }
4889 }
4890
4891 return sqlite3VdbeRecordCompare;
4892 }
4893
4894 /*
4895 ** pCur points at an index entry created using the OP_MakeRecord opcode.
4896 ** Read the rowid (the last field in the record) and store it in *rowid.
4897 ** Return SQLITE_OK if everything works, or an error code otherwise.
4898 **
4899 ** pCur might be pointing to text obtained from a corrupt database file.
4900 ** So the content cannot be trusted. Do appropriate checks on the content.
4901 */
sqlite3VdbeIdxRowid(sqlite3 * db,BtCursor * pCur,i64 * rowid)4902 int sqlite3VdbeIdxRowid(sqlite3 *db, BtCursor *pCur, i64 *rowid){
4903 i64 nCellKey = 0;
4904 int rc;
4905 u32 szHdr; /* Size of the header */
4906 u32 typeRowid; /* Serial type of the rowid */
4907 u32 lenRowid; /* Size of the rowid */
4908 Mem m, v;
4909
4910 /* Get the size of the index entry. Only indices entries of less
4911 ** than 2GiB are support - anything large must be database corruption.
4912 ** Any corruption is detected in sqlite3BtreeParseCellPtr(), though, so
4913 ** this code can safely assume that nCellKey is 32-bits
4914 */
4915 assert( sqlite3BtreeCursorIsValid(pCur) );
4916 nCellKey = sqlite3BtreePayloadSize(pCur);
4917 assert( (nCellKey & SQLITE_MAX_U32)==(u64)nCellKey );
4918
4919 /* Read in the complete content of the index entry */
4920 sqlite3VdbeMemInit(&m, db, 0);
4921 rc = sqlite3VdbeMemFromBtreeZeroOffset(pCur, (u32)nCellKey, &m);
4922 if( rc ){
4923 return rc;
4924 }
4925
4926 /* The index entry must begin with a header size */
4927 getVarint32NR((u8*)m.z, szHdr);
4928 testcase( szHdr==3 );
4929 testcase( szHdr==m.n );
4930 testcase( szHdr>0x7fffffff );
4931 assert( m.n>=0 );
4932 if( unlikely(szHdr<3 || szHdr>(unsigned)m.n) ){
4933 goto idx_rowid_corruption;
4934 }
4935
4936 /* The last field of the index should be an integer - the ROWID.
4937 ** Verify that the last entry really is an integer. */
4938 getVarint32NR((u8*)&m.z[szHdr-1], typeRowid);
4939 testcase( typeRowid==1 );
4940 testcase( typeRowid==2 );
4941 testcase( typeRowid==3 );
4942 testcase( typeRowid==4 );
4943 testcase( typeRowid==5 );
4944 testcase( typeRowid==6 );
4945 testcase( typeRowid==8 );
4946 testcase( typeRowid==9 );
4947 if( unlikely(typeRowid<1 || typeRowid>9 || typeRowid==7) ){
4948 goto idx_rowid_corruption;
4949 }
4950 lenRowid = sqlite3SmallTypeSizes[typeRowid];
4951 testcase( (u32)m.n==szHdr+lenRowid );
4952 if( unlikely((u32)m.n<szHdr+lenRowid) ){
4953 goto idx_rowid_corruption;
4954 }
4955
4956 /* Fetch the integer off the end of the index record */
4957 sqlite3VdbeSerialGet((u8*)&m.z[m.n-lenRowid], typeRowid, &v);
4958 *rowid = v.u.i;
4959 sqlite3VdbeMemRelease(&m);
4960 return SQLITE_OK;
4961
4962 /* Jump here if database corruption is detected after m has been
4963 ** allocated. Free the m object and return SQLITE_CORRUPT. */
4964 idx_rowid_corruption:
4965 testcase( m.szMalloc!=0 );
4966 sqlite3VdbeMemRelease(&m);
4967 return SQLITE_CORRUPT_BKPT;
4968 }
4969
4970 /*
4971 ** Compare the key of the index entry that cursor pC is pointing to against
4972 ** the key string in pUnpacked. Write into *pRes a number
4973 ** that is negative, zero, or positive if pC is less than, equal to,
4974 ** or greater than pUnpacked. Return SQLITE_OK on success.
4975 **
4976 ** pUnpacked is either created without a rowid or is truncated so that it
4977 ** omits the rowid at the end. The rowid at the end of the index entry
4978 ** is ignored as well. Hence, this routine only compares the prefixes
4979 ** of the keys prior to the final rowid, not the entire key.
4980 */
sqlite3VdbeIdxKeyCompare(sqlite3 * db,VdbeCursor * pC,UnpackedRecord * pUnpacked,int * res)4981 int sqlite3VdbeIdxKeyCompare(
4982 sqlite3 *db, /* Database connection */
4983 VdbeCursor *pC, /* The cursor to compare against */
4984 UnpackedRecord *pUnpacked, /* Unpacked version of key */
4985 int *res /* Write the comparison result here */
4986 ){
4987 i64 nCellKey = 0;
4988 int rc;
4989 BtCursor *pCur;
4990 Mem m;
4991
4992 assert( pC->eCurType==CURTYPE_BTREE );
4993 pCur = pC->uc.pCursor;
4994 assert( sqlite3BtreeCursorIsValid(pCur) );
4995 nCellKey = sqlite3BtreePayloadSize(pCur);
4996 /* nCellKey will always be between 0 and 0xffffffff because of the way
4997 ** that btreeParseCellPtr() and sqlite3GetVarint32() are implemented */
4998 if( nCellKey<=0 || nCellKey>0x7fffffff ){
4999 *res = 0;
5000 return SQLITE_CORRUPT_BKPT;
5001 }
5002 sqlite3VdbeMemInit(&m, db, 0);
5003 rc = sqlite3VdbeMemFromBtreeZeroOffset(pCur, (u32)nCellKey, &m);
5004 if( rc ){
5005 return rc;
5006 }
5007 *res = sqlite3VdbeRecordCompareWithSkip(m.n, m.z, pUnpacked, 0);
5008 sqlite3VdbeMemRelease(&m);
5009 return SQLITE_OK;
5010 }
5011
5012 /*
5013 ** This routine sets the value to be returned by subsequent calls to
5014 ** sqlite3_changes() on the database handle 'db'.
5015 */
sqlite3VdbeSetChanges(sqlite3 * db,int nChange)5016 void sqlite3VdbeSetChanges(sqlite3 *db, int nChange){
5017 assert( sqlite3_mutex_held(db->mutex) );
5018 db->nChange = nChange;
5019 db->nTotalChange += nChange;
5020 }
5021
5022 /*
5023 ** Set a flag in the vdbe to update the change counter when it is finalised
5024 ** or reset.
5025 */
sqlite3VdbeCountChanges(Vdbe * v)5026 void sqlite3VdbeCountChanges(Vdbe *v){
5027 v->changeCntOn = 1;
5028 }
5029
5030 /*
5031 ** Mark every prepared statement associated with a database connection
5032 ** as expired.
5033 **
5034 ** An expired statement means that recompilation of the statement is
5035 ** recommend. Statements expire when things happen that make their
5036 ** programs obsolete. Removing user-defined functions or collating
5037 ** sequences, or changing an authorization function are the types of
5038 ** things that make prepared statements obsolete.
5039 **
5040 ** If iCode is 1, then expiration is advisory. The statement should
5041 ** be reprepared before being restarted, but if it is already running
5042 ** it is allowed to run to completion.
5043 **
5044 ** Internally, this function just sets the Vdbe.expired flag on all
5045 ** prepared statements. The flag is set to 1 for an immediate expiration
5046 ** and set to 2 for an advisory expiration.
5047 */
sqlite3ExpirePreparedStatements(sqlite3 * db,int iCode)5048 void sqlite3ExpirePreparedStatements(sqlite3 *db, int iCode){
5049 Vdbe *p;
5050 for(p = db->pVdbe; p; p=p->pNext){
5051 p->expired = iCode+1;
5052 }
5053 }
5054
5055 /*
5056 ** Return the database associated with the Vdbe.
5057 */
sqlite3VdbeDb(Vdbe * v)5058 sqlite3 *sqlite3VdbeDb(Vdbe *v){
5059 return v->db;
5060 }
5061
5062 /*
5063 ** Return the SQLITE_PREPARE flags for a Vdbe.
5064 */
sqlite3VdbePrepareFlags(Vdbe * v)5065 u8 sqlite3VdbePrepareFlags(Vdbe *v){
5066 return v->prepFlags;
5067 }
5068
5069 /*
5070 ** Return a pointer to an sqlite3_value structure containing the value bound
5071 ** parameter iVar of VM v. Except, if the value is an SQL NULL, return
5072 ** 0 instead. Unless it is NULL, apply affinity aff (one of the SQLITE_AFF_*
5073 ** constants) to the value before returning it.
5074 **
5075 ** The returned value must be freed by the caller using sqlite3ValueFree().
5076 */
sqlite3VdbeGetBoundValue(Vdbe * v,int iVar,u8 aff)5077 sqlite3_value *sqlite3VdbeGetBoundValue(Vdbe *v, int iVar, u8 aff){
5078 assert( iVar>0 );
5079 if( v ){
5080 Mem *pMem = &v->aVar[iVar-1];
5081 assert( (v->db->flags & SQLITE_EnableQPSG)==0 );
5082 if( 0==(pMem->flags & MEM_Null) ){
5083 sqlite3_value *pRet = sqlite3ValueNew(v->db);
5084 if( pRet ){
5085 sqlite3VdbeMemCopy((Mem *)pRet, pMem);
5086 sqlite3ValueApplyAffinity(pRet, aff, SQLITE_UTF8);
5087 }
5088 return pRet;
5089 }
5090 }
5091 return 0;
5092 }
5093
5094 /*
5095 ** Configure SQL variable iVar so that binding a new value to it signals
5096 ** to sqlite3_reoptimize() that re-preparing the statement may result
5097 ** in a better query plan.
5098 */
sqlite3VdbeSetVarmask(Vdbe * v,int iVar)5099 void sqlite3VdbeSetVarmask(Vdbe *v, int iVar){
5100 assert( iVar>0 );
5101 assert( (v->db->flags & SQLITE_EnableQPSG)==0 );
5102 if( iVar>=32 ){
5103 v->expmask |= 0x80000000;
5104 }else{
5105 v->expmask |= ((u32)1 << (iVar-1));
5106 }
5107 }
5108
5109 /*
5110 ** Cause a function to throw an error if it was call from OP_PureFunc
5111 ** rather than OP_Function.
5112 **
5113 ** OP_PureFunc means that the function must be deterministic, and should
5114 ** throw an error if it is given inputs that would make it non-deterministic.
5115 ** This routine is invoked by date/time functions that use non-deterministic
5116 ** features such as 'now'.
5117 */
sqlite3NotPureFunc(sqlite3_context * pCtx)5118 int sqlite3NotPureFunc(sqlite3_context *pCtx){
5119 const VdbeOp *pOp;
5120 #ifdef SQLITE_ENABLE_STAT4
5121 if( pCtx->pVdbe==0 ) return 1;
5122 #endif
5123 pOp = pCtx->pVdbe->aOp + pCtx->iOp;
5124 if( pOp->opcode==OP_PureFunc ){
5125 const char *zContext;
5126 char *zMsg;
5127 if( pOp->p5 & NC_IsCheck ){
5128 zContext = "a CHECK constraint";
5129 }else if( pOp->p5 & NC_GenCol ){
5130 zContext = "a generated column";
5131 }else{
5132 zContext = "an index";
5133 }
5134 zMsg = sqlite3_mprintf("non-deterministic use of %s() in %s",
5135 pCtx->pFunc->zName, zContext);
5136 sqlite3_result_error(pCtx, zMsg, -1);
5137 sqlite3_free(zMsg);
5138 return 0;
5139 }
5140 return 1;
5141 }
5142
5143 #ifndef SQLITE_OMIT_VIRTUALTABLE
5144 /*
5145 ** Transfer error message text from an sqlite3_vtab.zErrMsg (text stored
5146 ** in memory obtained from sqlite3_malloc) into a Vdbe.zErrMsg (text stored
5147 ** in memory obtained from sqlite3DbMalloc).
5148 */
sqlite3VtabImportErrmsg(Vdbe * p,sqlite3_vtab * pVtab)5149 void sqlite3VtabImportErrmsg(Vdbe *p, sqlite3_vtab *pVtab){
5150 if( pVtab->zErrMsg ){
5151 sqlite3 *db = p->db;
5152 sqlite3DbFree(db, p->zErrMsg);
5153 p->zErrMsg = sqlite3DbStrDup(db, pVtab->zErrMsg);
5154 sqlite3_free(pVtab->zErrMsg);
5155 pVtab->zErrMsg = 0;
5156 }
5157 }
5158 #endif /* SQLITE_OMIT_VIRTUALTABLE */
5159
5160 #ifdef SQLITE_ENABLE_PREUPDATE_HOOK
5161
5162 /*
5163 ** If the second argument is not NULL, release any allocations associated
5164 ** with the memory cells in the p->aMem[] array. Also free the UnpackedRecord
5165 ** structure itself, using sqlite3DbFree().
5166 **
5167 ** This function is used to free UnpackedRecord structures allocated by
5168 ** the vdbeUnpackRecord() function found in vdbeapi.c.
5169 */
vdbeFreeUnpacked(sqlite3 * db,int nField,UnpackedRecord * p)5170 static void vdbeFreeUnpacked(sqlite3 *db, int nField, UnpackedRecord *p){
5171 if( p ){
5172 int i;
5173 for(i=0; i<nField; i++){
5174 Mem *pMem = &p->aMem[i];
5175 if( pMem->zMalloc ) sqlite3VdbeMemRelease(pMem);
5176 }
5177 sqlite3DbFreeNN(db, p);
5178 }
5179 }
5180 #endif /* SQLITE_ENABLE_PREUPDATE_HOOK */
5181
5182 #ifdef SQLITE_ENABLE_PREUPDATE_HOOK
5183 /*
5184 ** Invoke the pre-update hook. If this is an UPDATE or DELETE pre-update call,
5185 ** then cursor passed as the second argument should point to the row about
5186 ** to be update or deleted. If the application calls sqlite3_preupdate_old(),
5187 ** the required value will be read from the row the cursor points to.
5188 */
sqlite3VdbePreUpdateHook(Vdbe * v,VdbeCursor * pCsr,int op,const char * zDb,Table * pTab,i64 iKey1,int iReg)5189 void sqlite3VdbePreUpdateHook(
5190 Vdbe *v, /* Vdbe pre-update hook is invoked by */
5191 VdbeCursor *pCsr, /* Cursor to grab old.* values from */
5192 int op, /* SQLITE_INSERT, UPDATE or DELETE */
5193 const char *zDb, /* Database name */
5194 Table *pTab, /* Modified table */
5195 i64 iKey1, /* Initial key value */
5196 int iReg /* Register for new.* record */
5197 ){
5198 sqlite3 *db = v->db;
5199 i64 iKey2;
5200 PreUpdate preupdate;
5201 const char *zTbl = pTab->zName;
5202 static const u8 fakeSortOrder = 0;
5203
5204 assert( db->pPreUpdate==0 );
5205 memset(&preupdate, 0, sizeof(PreUpdate));
5206 if( HasRowid(pTab)==0 ){
5207 iKey1 = iKey2 = 0;
5208 preupdate.pPk = sqlite3PrimaryKeyIndex(pTab);
5209 }else{
5210 if( op==SQLITE_UPDATE ){
5211 iKey2 = v->aMem[iReg].u.i;
5212 }else{
5213 iKey2 = iKey1;
5214 }
5215 }
5216
5217 assert( pCsr->nField==pTab->nCol
5218 || (pCsr->nField==pTab->nCol+1 && op==SQLITE_DELETE && iReg==-1)
5219 );
5220
5221 preupdate.v = v;
5222 preupdate.pCsr = pCsr;
5223 preupdate.op = op;
5224 preupdate.iNewReg = iReg;
5225 preupdate.keyinfo.db = db;
5226 preupdate.keyinfo.enc = ENC(db);
5227 preupdate.keyinfo.nKeyField = pTab->nCol;
5228 preupdate.keyinfo.aSortFlags = (u8*)&fakeSortOrder;
5229 preupdate.iKey1 = iKey1;
5230 preupdate.iKey2 = iKey2;
5231 preupdate.pTab = pTab;
5232
5233 db->pPreUpdate = &preupdate;
5234 db->xPreUpdateCallback(db->pPreUpdateArg, db, op, zDb, zTbl, iKey1, iKey2);
5235 db->pPreUpdate = 0;
5236 sqlite3DbFree(db, preupdate.aRecord);
5237 vdbeFreeUnpacked(db, preupdate.keyinfo.nKeyField+1, preupdate.pUnpacked);
5238 vdbeFreeUnpacked(db, preupdate.keyinfo.nKeyField+1, preupdate.pNewUnpacked);
5239 if( preupdate.aNew ){
5240 int i;
5241 for(i=0; i<pCsr->nField; i++){
5242 sqlite3VdbeMemRelease(&preupdate.aNew[i]);
5243 }
5244 sqlite3DbFreeNN(db, preupdate.aNew);
5245 }
5246 }
5247 #endif /* SQLITE_ENABLE_PREUPDATE_HOOK */
5248