1 /*-------------------------------------------------------------------------
2  *
3  * libpq-fe.h
4  *	  This file contains definitions for structures and
5  *	  externs for functions used by frontend postgres applications.
6  *
7  * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
8  * Portions Copyright (c) 1994, Regents of the University of California
9  *
10  * src/interfaces/libpq/libpq-fe.h
11  *
12  *-------------------------------------------------------------------------
13  */
14 
15 #ifndef LIBPQ_FE_H
16 #define LIBPQ_FE_H
17 
18 #ifdef __cplusplus
19 extern "C"
20 {
21 #endif
22 
23 #include <stdio.h>
24 
25 /*
26  * postgres_ext.h defines the backend's externally visible types,
27  * such as Oid.
28  */
29 #include "postgres_ext.h"
30 
31 /*
32  * Option flags for PQcopyResult
33  */
34 #define PG_COPYRES_ATTRS		  0x01
35 #define PG_COPYRES_TUPLES		  0x02	/* Implies PG_COPYRES_ATTRS */
36 #define PG_COPYRES_EVENTS		  0x04
37 #define PG_COPYRES_NOTICEHOOKS	  0x08
38 
39 /* Application-visible enum types */
40 
41 /*
42  * Although it is okay to add to these lists, values which become unused
43  * should never be removed, nor should constants be redefined - that would
44  * break compatibility with existing code.
45  */
46 
47 typedef enum
48 {
49 	CONNECTION_OK,
50 	CONNECTION_BAD,
51 	/* Non-blocking mode only below here */
52 
53 	/*
54 	 * The existence of these should never be relied upon - they should only
55 	 * be used for user feedback or similar purposes.
56 	 */
57 	CONNECTION_STARTED,			/* Waiting for connection to be made.  */
58 	CONNECTION_MADE,			/* Connection OK; waiting to send.     */
59 	CONNECTION_AWAITING_RESPONSE,	/* Waiting for a response from the
60 									 * postmaster.        */
61 	CONNECTION_AUTH_OK,			/* Received authentication; waiting for
62 								 * backend startup. */
63 	CONNECTION_SETENV,			/* Negotiating environment. */
64 	CONNECTION_SSL_STARTUP,		/* Negotiating SSL. */
65 	CONNECTION_NEEDED,			/* Internal state: connect() needed */
66 	CONNECTION_CHECK_WRITABLE,	/* Check if we could make a writable
67 								 * connection. */
68 	CONNECTION_CONSUME			/* Wait for any pending message and consume
69 								 * them. */
70 } ConnStatusType;
71 
72 typedef enum
73 {
74 	PGRES_POLLING_FAILED = 0,
75 	PGRES_POLLING_READING,		/* These two indicate that one may	  */
76 	PGRES_POLLING_WRITING,		/* use select before polling again.   */
77 	PGRES_POLLING_OK,
78 	PGRES_POLLING_ACTIVE		/* unused; keep for awhile for backwards
79 								 * compatibility */
80 } PostgresPollingStatusType;
81 
82 typedef enum
83 {
84 	PGRES_EMPTY_QUERY = 0,		/* empty query string was executed */
85 	PGRES_COMMAND_OK,			/* a query command that doesn't return
86 								 * anything was executed properly by the
87 								 * backend */
88 	PGRES_TUPLES_OK,			/* a query command that returns tuples was
89 								 * executed properly by the backend, PGresult
90 								 * contains the result tuples */
91 	PGRES_COPY_OUT,				/* Copy Out data transfer in progress */
92 	PGRES_COPY_IN,				/* Copy In data transfer in progress */
93 	PGRES_BAD_RESPONSE,			/* an unexpected response was recv'd from the
94 								 * backend */
95 	PGRES_NONFATAL_ERROR,		/* notice or warning message */
96 	PGRES_FATAL_ERROR,			/* query failed */
97 	PGRES_COPY_BOTH,			/* Copy In/Out data transfer in progress */
98 	PGRES_SINGLE_TUPLE			/* single tuple from larger resultset */
99 } ExecStatusType;
100 
101 typedef enum
102 {
103 	PQTRANS_IDLE,				/* connection idle */
104 	PQTRANS_ACTIVE,				/* command in progress */
105 	PQTRANS_INTRANS,			/* idle, within transaction block */
106 	PQTRANS_INERROR,			/* idle, within failed transaction */
107 	PQTRANS_UNKNOWN				/* cannot determine status */
108 } PGTransactionStatusType;
109 
110 typedef enum
111 {
112 	PQERRORS_TERSE,				/* single-line error messages */
113 	PQERRORS_DEFAULT,			/* recommended style */
114 	PQERRORS_VERBOSE			/* all the facts, ma'am */
115 } PGVerbosity;
116 
117 typedef enum
118 {
119 	PQSHOW_CONTEXT_NEVER,		/* never show CONTEXT field */
120 	PQSHOW_CONTEXT_ERRORS,		/* show CONTEXT for errors only (default) */
121 	PQSHOW_CONTEXT_ALWAYS		/* always show CONTEXT field */
122 } PGContextVisibility;
123 
124 /*
125  * PGPing - The ordering of this enum should not be altered because the
126  * values are exposed externally via pg_isready.
127  */
128 
129 typedef enum
130 {
131 	PQPING_OK,					/* server is accepting connections */
132 	PQPING_REJECT,				/* server is alive but rejecting connections */
133 	PQPING_NO_RESPONSE,			/* could not establish connection */
134 	PQPING_NO_ATTEMPT			/* connection not attempted (bad params) */
135 } PGPing;
136 
137 /* PGconn encapsulates a connection to the backend.
138  * The contents of this struct are not supposed to be known to applications.
139  */
140 typedef struct pg_conn PGconn;
141 
142 /* PGresult encapsulates the result of a query (or more precisely, of a single
143  * SQL command --- a query string given to PQsendQuery can contain multiple
144  * commands and thus return multiple PGresult objects).
145  * The contents of this struct are not supposed to be known to applications.
146  */
147 typedef struct pg_result PGresult;
148 
149 /* PGcancel encapsulates the information needed to cancel a running
150  * query on an existing connection.
151  * The contents of this struct are not supposed to be known to applications.
152  */
153 typedef struct pg_cancel PGcancel;
154 
155 /* PGnotify represents the occurrence of a NOTIFY message.
156  * Ideally this would be an opaque typedef, but it's so simple that it's
157  * unlikely to change.
158  * NOTE: in Postgres 6.4 and later, the be_pid is the notifying backend's,
159  * whereas in earlier versions it was always your own backend's PID.
160  */
161 typedef struct pgNotify
162 {
163 	char	   *relname;		/* notification condition name */
164 	int			be_pid;			/* process ID of notifying server process */
165 	char	   *extra;			/* notification parameter */
166 	/* Fields below here are private to libpq; apps should not use 'em */
167 	struct pgNotify *next;		/* list link */
168 } PGnotify;
169 
170 /* Function types for notice-handling callbacks */
171 typedef void (*PQnoticeReceiver) (void *arg, const PGresult *res);
172 typedef void (*PQnoticeProcessor) (void *arg, const char *message);
173 
174 /* Print options for PQprint() */
175 typedef char pqbool;
176 
177 typedef struct _PQprintOpt
178 {
179 	pqbool		header;			/* print output field headings and row count */
180 	pqbool		align;			/* fill align the fields */
181 	pqbool		standard;		/* old brain dead format */
182 	pqbool		html3;			/* output html tables */
183 	pqbool		expanded;		/* expand tables */
184 	pqbool		pager;			/* use pager for output if needed */
185 	char	   *fieldSep;		/* field separator */
186 	char	   *tableOpt;		/* insert to HTML <table ...> */
187 	char	   *caption;		/* HTML <caption> */
188 	char	  **fieldName;		/* null terminated array of replacement field
189 								 * names */
190 } PQprintOpt;
191 
192 /* ----------------
193  * Structure for the conninfo parameter definitions returned by PQconndefaults
194  * or PQconninfoParse.
195  *
196  * All fields except "val" point at static strings which must not be altered.
197  * "val" is either NULL or a malloc'd current-value string.  PQconninfoFree()
198  * will release both the val strings and the PQconninfoOption array itself.
199  * ----------------
200  */
201 typedef struct _PQconninfoOption
202 {
203 	char	   *keyword;		/* The keyword of the option			*/
204 	char	   *envvar;			/* Fallback environment variable name	*/
205 	char	   *compiled;		/* Fallback compiled in default value	*/
206 	char	   *val;			/* Option's current value, or NULL		 */
207 	char	   *label;			/* Label for field in connect dialog	*/
208 	char	   *dispchar;		/* Indicates how to display this field in a
209 								 * connect dialog. Values are: "" Display
210 								 * entered value as is "*" Password field -
211 								 * hide value "D"  Debug option - don't show
212 								 * by default */
213 	int			dispsize;		/* Field size in characters for dialog	*/
214 } PQconninfoOption;
215 
216 /* ----------------
217  * PQArgBlock -- structure for PQfn() arguments
218  * ----------------
219  */
220 typedef struct
221 {
222 	int			len;
223 	int			isint;
224 	union
225 	{
226 		int		   *ptr;		/* can't use void (dec compiler barfs)	 */
227 		int			integer;
228 	}			u;
229 } PQArgBlock;
230 
231 /* ----------------
232  * PGresAttDesc -- Data about a single attribute (column) of a query result
233  * ----------------
234  */
235 typedef struct pgresAttDesc
236 {
237 	char	   *name;			/* column name */
238 	Oid			tableid;		/* source table, if known */
239 	int			columnid;		/* source column, if known */
240 	int			format;			/* format code for value (text/binary) */
241 	Oid			typid;			/* type id */
242 	int			typlen;			/* type size */
243 	int			atttypmod;		/* type-specific modifier info */
244 } PGresAttDesc;
245 
246 /* ----------------
247  * Exported functions of libpq
248  * ----------------
249  */
250 
251 /* ===	in fe-connect.c === */
252 
253 /* make a new client connection to the backend */
254 /* Asynchronous (non-blocking) */
255 extern PGconn *PQconnectStart(const char *conninfo);
256 extern PGconn *PQconnectStartParams(const char *const *keywords,
257 					 const char *const *values, int expand_dbname);
258 extern PostgresPollingStatusType PQconnectPoll(PGconn *conn);
259 
260 /* Synchronous (blocking) */
261 extern PGconn *PQconnectdb(const char *conninfo);
262 extern PGconn *PQconnectdbParams(const char *const *keywords,
263 				  const char *const *values, int expand_dbname);
264 extern PGconn *PQsetdbLogin(const char *pghost, const char *pgport,
265 			 const char *pgoptions, const char *pgtty,
266 			 const char *dbName,
267 			 const char *login, const char *pwd);
268 
269 #define PQsetdb(M_PGHOST,M_PGPORT,M_PGOPT,M_PGTTY,M_DBNAME)  \
270 	PQsetdbLogin(M_PGHOST, M_PGPORT, M_PGOPT, M_PGTTY, M_DBNAME, NULL, NULL)
271 
272 /* close the current connection and free the PGconn data structure */
273 extern void PQfinish(PGconn *conn);
274 
275 /* get info about connection options known to PQconnectdb */
276 extern PQconninfoOption *PQconndefaults(void);
277 
278 /* parse connection options in same way as PQconnectdb */
279 extern PQconninfoOption *PQconninfoParse(const char *conninfo, char **errmsg);
280 
281 /* return the connection options used by a live connection */
282 extern PQconninfoOption *PQconninfo(PGconn *conn);
283 
284 /* free the data structure returned by PQconndefaults() or PQconninfoParse() */
285 extern void PQconninfoFree(PQconninfoOption *connOptions);
286 
287 /*
288  * close the current connection and restablish a new one with the same
289  * parameters
290  */
291 /* Asynchronous (non-blocking) */
292 extern int	PQresetStart(PGconn *conn);
293 extern PostgresPollingStatusType PQresetPoll(PGconn *conn);
294 
295 /* Synchronous (blocking) */
296 extern void PQreset(PGconn *conn);
297 
298 /* request a cancel structure */
299 extern PGcancel *PQgetCancel(PGconn *conn);
300 
301 /* free a cancel structure */
302 extern void PQfreeCancel(PGcancel *cancel);
303 
304 /* issue a cancel request */
305 extern int	PQcancel(PGcancel *cancel, char *errbuf, int errbufsize);
306 
307 /* backwards compatible version of PQcancel; not thread-safe */
308 extern int	PQrequestCancel(PGconn *conn);
309 
310 /* Accessor functions for PGconn objects */
311 extern char *PQdb(const PGconn *conn);
312 extern char *PQuser(const PGconn *conn);
313 extern char *PQpass(const PGconn *conn);
314 extern char *PQhost(const PGconn *conn);
315 extern char *PQport(const PGconn *conn);
316 extern char *PQtty(const PGconn *conn);
317 extern char *PQoptions(const PGconn *conn);
318 extern ConnStatusType PQstatus(const PGconn *conn);
319 extern PGTransactionStatusType PQtransactionStatus(const PGconn *conn);
320 extern const char *PQparameterStatus(const PGconn *conn,
321 				  const char *paramName);
322 extern int	PQprotocolVersion(const PGconn *conn);
323 extern int	PQserverVersion(const PGconn *conn);
324 extern char *PQerrorMessage(const PGconn *conn);
325 extern int	PQsocket(const PGconn *conn);
326 extern int	PQbackendPID(const PGconn *conn);
327 extern int	PQconnectionNeedsPassword(const PGconn *conn);
328 extern int	PQconnectionUsedPassword(const PGconn *conn);
329 extern int	PQclientEncoding(const PGconn *conn);
330 extern int	PQsetClientEncoding(PGconn *conn, const char *encoding);
331 
332 /* SSL information functions */
333 extern int	PQsslInUse(PGconn *conn);
334 extern void *PQsslStruct(PGconn *conn, const char *struct_name);
335 extern const char *PQsslAttribute(PGconn *conn, const char *attribute_name);
336 extern const char *const *PQsslAttributeNames(PGconn *conn);
337 
338 /* Get the OpenSSL structure associated with a connection. Returns NULL for
339  * unencrypted connections or if any other TLS library is in use. */
340 extern void *PQgetssl(PGconn *conn);
341 
342 /* Tell libpq whether it needs to initialize OpenSSL */
343 extern void PQinitSSL(int do_init);
344 
345 /* More detailed way to tell libpq whether it needs to initialize OpenSSL */
346 extern void PQinitOpenSSL(int do_ssl, int do_crypto);
347 
348 /* Set verbosity for PQerrorMessage and PQresultErrorMessage */
349 extern PGVerbosity PQsetErrorVerbosity(PGconn *conn, PGVerbosity verbosity);
350 
351 /* Set CONTEXT visibility for PQerrorMessage and PQresultErrorMessage */
352 extern PGContextVisibility PQsetErrorContextVisibility(PGconn *conn,
353 							PGContextVisibility show_context);
354 
355 /* Enable/disable tracing */
356 extern void PQtrace(PGconn *conn, FILE *debug_port);
357 extern void PQuntrace(PGconn *conn);
358 
359 /* Override default notice handling routines */
360 extern PQnoticeReceiver PQsetNoticeReceiver(PGconn *conn,
361 					PQnoticeReceiver proc,
362 					void *arg);
363 extern PQnoticeProcessor PQsetNoticeProcessor(PGconn *conn,
364 					 PQnoticeProcessor proc,
365 					 void *arg);
366 
367 /*
368  *	   Used to set callback that prevents concurrent access to
369  *	   non-thread safe functions that libpq needs.
370  *	   The default implementation uses a libpq internal mutex.
371  *	   Only required for multithreaded apps that use kerberos
372  *	   both within their app and for postgresql connections.
373  */
374 typedef void (*pgthreadlock_t) (int acquire);
375 
376 extern pgthreadlock_t PQregisterThreadLock(pgthreadlock_t newhandler);
377 
378 /* === in fe-exec.c === */
379 
380 /* Simple synchronous query */
381 extern PGresult *PQexec(PGconn *conn, const char *query);
382 extern PGresult *PQexecParams(PGconn *conn,
383 			 const char *command,
384 			 int nParams,
385 			 const Oid *paramTypes,
386 			 const char *const *paramValues,
387 			 const int *paramLengths,
388 			 const int *paramFormats,
389 			 int resultFormat);
390 extern PGresult *PQprepare(PGconn *conn, const char *stmtName,
391 		  const char *query, int nParams,
392 		  const Oid *paramTypes);
393 extern PGresult *PQexecPrepared(PGconn *conn,
394 			   const char *stmtName,
395 			   int nParams,
396 			   const char *const *paramValues,
397 			   const int *paramLengths,
398 			   const int *paramFormats,
399 			   int resultFormat);
400 
401 /* Interface for multiple-result or asynchronous queries */
402 extern int	PQsendQuery(PGconn *conn, const char *query);
403 extern int PQsendQueryParams(PGconn *conn,
404 				  const char *command,
405 				  int nParams,
406 				  const Oid *paramTypes,
407 				  const char *const *paramValues,
408 				  const int *paramLengths,
409 				  const int *paramFormats,
410 				  int resultFormat);
411 extern int PQsendPrepare(PGconn *conn, const char *stmtName,
412 			  const char *query, int nParams,
413 			  const Oid *paramTypes);
414 extern int PQsendQueryPrepared(PGconn *conn,
415 					const char *stmtName,
416 					int nParams,
417 					const char *const *paramValues,
418 					const int *paramLengths,
419 					const int *paramFormats,
420 					int resultFormat);
421 extern int	PQsetSingleRowMode(PGconn *conn);
422 extern PGresult *PQgetResult(PGconn *conn);
423 
424 /* Routines for managing an asynchronous query */
425 extern int	PQisBusy(PGconn *conn);
426 extern int	PQconsumeInput(PGconn *conn);
427 
428 /* LISTEN/NOTIFY support */
429 extern PGnotify *PQnotifies(PGconn *conn);
430 
431 /* Routines for copy in/out */
432 extern int	PQputCopyData(PGconn *conn, const char *buffer, int nbytes);
433 extern int	PQputCopyEnd(PGconn *conn, const char *errormsg);
434 extern int	PQgetCopyData(PGconn *conn, char **buffer, int async);
435 
436 /* Deprecated routines for copy in/out */
437 extern int	PQgetline(PGconn *conn, char *string, int length);
438 extern int	PQputline(PGconn *conn, const char *string);
439 extern int	PQgetlineAsync(PGconn *conn, char *buffer, int bufsize);
440 extern int	PQputnbytes(PGconn *conn, const char *buffer, int nbytes);
441 extern int	PQendcopy(PGconn *conn);
442 
443 /* Set blocking/nonblocking connection to the backend */
444 extern int	PQsetnonblocking(PGconn *conn, int arg);
445 extern int	PQisnonblocking(const PGconn *conn);
446 extern int	PQisthreadsafe(void);
447 extern PGPing PQping(const char *conninfo);
448 extern PGPing PQpingParams(const char *const *keywords,
449 			 const char *const *values, int expand_dbname);
450 
451 /* Force the write buffer to be written (or at least try) */
452 extern int	PQflush(PGconn *conn);
453 
454 /*
455  * "Fast path" interface --- not really recommended for application
456  * use
457  */
458 extern PGresult *PQfn(PGconn *conn,
459 	 int fnid,
460 	 int *result_buf,
461 	 int *result_len,
462 	 int result_is_int,
463 	 const PQArgBlock *args,
464 	 int nargs);
465 
466 /* Accessor functions for PGresult objects */
467 extern ExecStatusType PQresultStatus(const PGresult *res);
468 extern char *PQresStatus(ExecStatusType status);
469 extern char *PQresultErrorMessage(const PGresult *res);
470 extern char *PQresultVerboseErrorMessage(const PGresult *res,
471 							PGVerbosity verbosity,
472 							PGContextVisibility show_context);
473 extern char *PQresultErrorField(const PGresult *res, int fieldcode);
474 extern int	PQntuples(const PGresult *res);
475 extern int	PQnfields(const PGresult *res);
476 extern int	PQbinaryTuples(const PGresult *res);
477 extern char *PQfname(const PGresult *res, int field_num);
478 extern int	PQfnumber(const PGresult *res, const char *field_name);
479 extern Oid	PQftable(const PGresult *res, int field_num);
480 extern int	PQftablecol(const PGresult *res, int field_num);
481 extern int	PQfformat(const PGresult *res, int field_num);
482 extern Oid	PQftype(const PGresult *res, int field_num);
483 extern int	PQfsize(const PGresult *res, int field_num);
484 extern int	PQfmod(const PGresult *res, int field_num);
485 extern char *PQcmdStatus(PGresult *res);
486 extern char *PQoidStatus(const PGresult *res);	/* old and ugly */
487 extern Oid	PQoidValue(const PGresult *res);	/* new and improved */
488 extern char *PQcmdTuples(PGresult *res);
489 extern char *PQgetvalue(const PGresult *res, int tup_num, int field_num);
490 extern int	PQgetlength(const PGresult *res, int tup_num, int field_num);
491 extern int	PQgetisnull(const PGresult *res, int tup_num, int field_num);
492 extern int	PQnparams(const PGresult *res);
493 extern Oid	PQparamtype(const PGresult *res, int param_num);
494 
495 /* Describe prepared statements and portals */
496 extern PGresult *PQdescribePrepared(PGconn *conn, const char *stmt);
497 extern PGresult *PQdescribePortal(PGconn *conn, const char *portal);
498 extern int	PQsendDescribePrepared(PGconn *conn, const char *stmt);
499 extern int	PQsendDescribePortal(PGconn *conn, const char *portal);
500 
501 /* Delete a PGresult */
502 extern void PQclear(PGresult *res);
503 
504 /* For freeing other alloc'd results, such as PGnotify structs */
505 extern void PQfreemem(void *ptr);
506 
507 /* Exists for backward compatibility.  bjm 2003-03-24 */
508 #define PQfreeNotify(ptr) PQfreemem(ptr)
509 
510 /* Error when no password was given. */
511 /* Note: depending on this is deprecated; use PQconnectionNeedsPassword(). */
512 #define PQnoPasswordSupplied	"fe_sendauth: no password supplied\n"
513 
514 /* Create and manipulate PGresults */
515 extern PGresult *PQmakeEmptyPGresult(PGconn *conn, ExecStatusType status);
516 extern PGresult *PQcopyResult(const PGresult *src, int flags);
517 extern int	PQsetResultAttrs(PGresult *res, int numAttributes, PGresAttDesc *attDescs);
518 extern void *PQresultAlloc(PGresult *res, size_t nBytes);
519 extern int	PQsetvalue(PGresult *res, int tup_num, int field_num, char *value, int len);
520 
521 /* Quoting strings before inclusion in queries. */
522 extern size_t PQescapeStringConn(PGconn *conn,
523 				   char *to, const char *from, size_t length,
524 				   int *error);
525 extern char *PQescapeLiteral(PGconn *conn, const char *str, size_t len);
526 extern char *PQescapeIdentifier(PGconn *conn, const char *str, size_t len);
527 extern unsigned char *PQescapeByteaConn(PGconn *conn,
528 				  const unsigned char *from, size_t from_length,
529 				  size_t *to_length);
530 extern unsigned char *PQunescapeBytea(const unsigned char *strtext,
531 				size_t *retbuflen);
532 
533 /* These forms are deprecated! */
534 extern size_t PQescapeString(char *to, const char *from, size_t length);
535 extern unsigned char *PQescapeBytea(const unsigned char *from, size_t from_length,
536 			  size_t *to_length);
537 
538 
539 
540 /* === in fe-print.c === */
541 
542 extern void PQprint(FILE *fout,				/* output stream */
543 		const PGresult *res,
544 		const PQprintOpt *ps);	/* option structure */
545 
546 /*
547  * really old printing routines
548  */
549 extern void PQdisplayTuples(const PGresult *res,
550 				FILE *fp,		/* where to send the output */
551 				int fillAlign,	/* pad the fields with spaces */
552 				const char *fieldSep,	/* field separator */
553 				int printHeader,	/* display headers? */
554 				int quiet);
555 
556 extern void PQprintTuples(const PGresult *res,
557 			  FILE *fout,		/* output stream */
558 			  int printAttName, /* print attribute names */
559 			  int terseOutput,	/* delimiter bars */
560 			  int width);		/* width of column, if 0, use variable width */
561 
562 
563 /* === in fe-lobj.c === */
564 
565 /* Large-object access routines */
566 extern int	lo_open(PGconn *conn, Oid lobjId, int mode);
567 extern int	lo_close(PGconn *conn, int fd);
568 extern int	lo_read(PGconn *conn, int fd, char *buf, size_t len);
569 extern int	lo_write(PGconn *conn, int fd, const char *buf, size_t len);
570 extern int	lo_lseek(PGconn *conn, int fd, int offset, int whence);
571 extern pg_int64 lo_lseek64(PGconn *conn, int fd, pg_int64 offset, int whence);
572 extern Oid	lo_creat(PGconn *conn, int mode);
573 extern Oid	lo_create(PGconn *conn, Oid lobjId);
574 extern int	lo_tell(PGconn *conn, int fd);
575 extern pg_int64 lo_tell64(PGconn *conn, int fd);
576 extern int	lo_truncate(PGconn *conn, int fd, size_t len);
577 extern int	lo_truncate64(PGconn *conn, int fd, pg_int64 len);
578 extern int	lo_unlink(PGconn *conn, Oid lobjId);
579 extern Oid	lo_import(PGconn *conn, const char *filename);
580 extern Oid	lo_import_with_oid(PGconn *conn, const char *filename, Oid lobjId);
581 extern int	lo_export(PGconn *conn, Oid lobjId, const char *filename);
582 
583 /* === in fe-misc.c === */
584 
585 /* Get the version of the libpq library in use */
586 extern int	PQlibVersion(void);
587 
588 /* Determine length of multibyte encoded char at *s */
589 extern int	PQmblen(const char *s, int encoding);
590 
591 /* Determine display length of multibyte encoded char at *s */
592 extern int	PQdsplen(const char *s, int encoding);
593 
594 /* Get encoding id from environment variable PGCLIENTENCODING */
595 extern int	PQenv2encoding(void);
596 
597 /* === in fe-auth.c === */
598 
599 extern char *PQencryptPassword(const char *passwd, const char *user);
600 extern char *PQencryptPasswordConn(PGconn *conn, const char *passwd, const char *user, const char *algorithm);
601 
602 /* === in encnames.c === */
603 
604 extern int	pg_char_to_encoding(const char *name);
605 extern const char *pg_encoding_to_char(int encoding);
606 extern int	pg_valid_server_encoding_id(int encoding);
607 
608 #ifdef __cplusplus
609 }
610 #endif
611 
612 #endif							/* LIBPQ_FE_H */
613