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fe-exec.c
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1 /*-------------------------------------------------------------------------
2  *
3  * fe-exec.c
4  * functions related to sending a query down to the backend
5  *
6  * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  *
10  * IDENTIFICATION
11  * src/interfaces/libpq/fe-exec.c
12  *
13  *-------------------------------------------------------------------------
14  */
15 #include "postgres_fe.h"
16 
17 #include <ctype.h>
18 #include <fcntl.h>
19 #include <limits.h>
20 
21 #include "libpq-fe.h"
22 #include "libpq-int.h"
23 
24 #include "mb/pg_wchar.h"
25 
26 #ifdef WIN32
27 #include "win32.h"
28 #else
29 #include <unistd.h>
30 #endif
31 
32 /* keep this in same order as ExecStatusType in libpq-fe.h */
33 char *const pgresStatus[] = {
34  "PGRES_EMPTY_QUERY",
35  "PGRES_COMMAND_OK",
36  "PGRES_TUPLES_OK",
37  "PGRES_COPY_OUT",
38  "PGRES_COPY_IN",
39  "PGRES_BAD_RESPONSE",
40  "PGRES_NONFATAL_ERROR",
41  "PGRES_FATAL_ERROR",
42  "PGRES_COPY_BOTH",
43  "PGRES_SINGLE_TUPLE"
44 };
45 
46 /*
47  * static state needed by PQescapeString and PQescapeBytea; initialize to
48  * values that result in backward-compatible behavior
49  */
51 static bool static_std_strings = false;
52 
53 
54 static PGEvent *dupEvents(PGEvent *events, int count, size_t *memSize);
55 static bool pqAddTuple(PGresult *res, PGresAttValue *tup,
56  const char **errmsgp);
57 static bool PQsendQueryStart(PGconn *conn);
58 static int PQsendQueryGuts(PGconn *conn,
59  const char *command,
60  const char *stmtName,
61  int nParams,
62  const Oid *paramTypes,
63  const char *const *paramValues,
64  const int *paramLengths,
65  const int *paramFormats,
66  int resultFormat);
67 static void parseInput(PGconn *conn);
68 static PGresult *getCopyResult(PGconn *conn, ExecStatusType copytype);
69 static bool PQexecStart(PGconn *conn);
71 static int PQsendDescribe(PGconn *conn, char desc_type,
72  const char *desc_target);
73 static int check_field_number(const PGresult *res, int field_num);
74 
75 
76 /* ----------------
77  * Space management for PGresult.
78  *
79  * Formerly, libpq did a separate malloc() for each field of each tuple
80  * returned by a query. This was remarkably expensive --- malloc/free
81  * consumed a sizable part of the application's runtime. And there is
82  * no real need to keep track of the fields separately, since they will
83  * all be freed together when the PGresult is released. So now, we grab
84  * large blocks of storage from malloc and allocate space for query data
85  * within these blocks, using a trivially simple allocator. This reduces
86  * the number of malloc/free calls dramatically, and it also avoids
87  * fragmentation of the malloc storage arena.
88  * The PGresult structure itself is still malloc'd separately. We could
89  * combine it with the first allocation block, but that would waste space
90  * for the common case that no extra storage is actually needed (that is,
91  * the SQL command did not return tuples).
92  *
93  * We also malloc the top-level array of tuple pointers separately, because
94  * we need to be able to enlarge it via realloc, and our trivial space
95  * allocator doesn't handle that effectively. (Too bad the FE/BE protocol
96  * doesn't tell us up front how many tuples will be returned.)
97  * All other subsidiary storage for a PGresult is kept in PGresult_data blocks
98  * of size PGRESULT_DATA_BLOCKSIZE. The overhead at the start of each block
99  * is just a link to the next one, if any. Free-space management info is
100  * kept in the owning PGresult.
101  * A query returning a small amount of data will thus require three malloc
102  * calls: one for the PGresult, one for the tuples pointer array, and one
103  * PGresult_data block.
104  *
105  * Only the most recently allocated PGresult_data block is a candidate to
106  * have more stuff added to it --- any extra space left over in older blocks
107  * is wasted. We could be smarter and search the whole chain, but the point
108  * here is to be simple and fast. Typical applications do not keep a PGresult
109  * around very long anyway, so some wasted space within one is not a problem.
110  *
111  * Tuning constants for the space allocator are:
112  * PGRESULT_DATA_BLOCKSIZE: size of a standard allocation block, in bytes
113  * PGRESULT_ALIGN_BOUNDARY: assumed alignment requirement for binary data
114  * PGRESULT_SEP_ALLOC_THRESHOLD: objects bigger than this are given separate
115  * blocks, instead of being crammed into a regular allocation block.
116  * Requirements for correct function are:
117  * PGRESULT_ALIGN_BOUNDARY must be a multiple of the alignment requirements
118  * of all machine data types. (Currently this is set from configure
119  * tests, so it should be OK automatically.)
120  * PGRESULT_SEP_ALLOC_THRESHOLD + PGRESULT_BLOCK_OVERHEAD <=
121  * PGRESULT_DATA_BLOCKSIZE
122  * pqResultAlloc assumes an object smaller than the threshold will fit
123  * in a new block.
124  * The amount of space wasted at the end of a block could be as much as
125  * PGRESULT_SEP_ALLOC_THRESHOLD, so it doesn't pay to make that too large.
126  * ----------------
127  */
128 
129 #define PGRESULT_DATA_BLOCKSIZE 2048
130 #define PGRESULT_ALIGN_BOUNDARY MAXIMUM_ALIGNOF /* from configure */
131 #define PGRESULT_BLOCK_OVERHEAD Max(sizeof(PGresult_data), PGRESULT_ALIGN_BOUNDARY)
132 #define PGRESULT_SEP_ALLOC_THRESHOLD (PGRESULT_DATA_BLOCKSIZE / 2)
133 
134 
135 /*
136  * PQmakeEmptyPGresult
137  * returns a newly allocated, initialized PGresult with given status.
138  * If conn is not NULL and status indicates an error, the conn's
139  * errorMessage is copied. Also, any PGEvents are copied from the conn.
140  */
141 PGresult *
143 {
144  PGresult *result;
145 
146  result = (PGresult *) malloc(sizeof(PGresult));
147  if (!result)
148  return NULL;
149 
150  result->ntups = 0;
151  result->numAttributes = 0;
152  result->attDescs = NULL;
153  result->tuples = NULL;
154  result->tupArrSize = 0;
155  result->numParameters = 0;
156  result->paramDescs = NULL;
157  result->resultStatus = status;
158  result->cmdStatus[0] = '\0';
159  result->binary = 0;
160  result->events = NULL;
161  result->nEvents = 0;
162  result->errMsg = NULL;
163  result->errFields = NULL;
164  result->errQuery = NULL;
165  result->null_field[0] = '\0';
166  result->curBlock = NULL;
167  result->curOffset = 0;
168  result->spaceLeft = 0;
169  result->memorySize = sizeof(PGresult);
170 
171  if (conn)
172  {
173  /* copy connection data we might need for operations on PGresult */
174  result->noticeHooks = conn->noticeHooks;
175  result->client_encoding = conn->client_encoding;
176 
177  /* consider copying conn's errorMessage */
178  switch (status)
179  {
180  case PGRES_EMPTY_QUERY:
181  case PGRES_COMMAND_OK:
182  case PGRES_TUPLES_OK:
183  case PGRES_COPY_OUT:
184  case PGRES_COPY_IN:
185  case PGRES_COPY_BOTH:
186  case PGRES_SINGLE_TUPLE:
187  /* non-error cases */
188  break;
189  default:
190  pqSetResultError(result, conn->errorMessage.data);
191  break;
192  }
193 
194  /* copy events last; result must be valid if we need to PQclear */
195  if (conn->nEvents > 0)
196  {
197  result->events = dupEvents(conn->events, conn->nEvents,
198  &result->memorySize);
199  if (!result->events)
200  {
201  PQclear(result);
202  return NULL;
203  }
204  result->nEvents = conn->nEvents;
205  }
206  }
207  else
208  {
209  /* defaults... */
210  result->noticeHooks.noticeRec = NULL;
211  result->noticeHooks.noticeRecArg = NULL;
212  result->noticeHooks.noticeProc = NULL;
213  result->noticeHooks.noticeProcArg = NULL;
214  result->client_encoding = PG_SQL_ASCII;
215  }
216 
217  return result;
218 }
219 
220 /*
221  * PQsetResultAttrs
222  *
223  * Set the attributes for a given result. This function fails if there are
224  * already attributes contained in the provided result. The call is
225  * ignored if numAttributes is zero or attDescs is NULL. If the
226  * function fails, it returns zero. If the function succeeds, it
227  * returns a non-zero value.
228  */
229 int
230 PQsetResultAttrs(PGresult *res, int numAttributes, PGresAttDesc *attDescs)
231 {
232  int i;
233 
234  /* If attrs already exist, they cannot be overwritten. */
235  if (!res || res->numAttributes > 0)
236  return false;
237 
238  /* ignore no-op request */
239  if (numAttributes <= 0 || !attDescs)
240  return true;
241 
242  res->attDescs = (PGresAttDesc *)
243  PQresultAlloc(res, numAttributes * sizeof(PGresAttDesc));
244 
245  if (!res->attDescs)
246  return false;
247 
248  res->numAttributes = numAttributes;
249  memcpy(res->attDescs, attDescs, numAttributes * sizeof(PGresAttDesc));
250 
251  /* deep-copy the attribute names, and determine format */
252  res->binary = 1;
253  for (i = 0; i < res->numAttributes; i++)
254  {
255  if (res->attDescs[i].name)
256  res->attDescs[i].name = pqResultStrdup(res, res->attDescs[i].name);
257  else
258  res->attDescs[i].name = res->null_field;
259 
260  if (!res->attDescs[i].name)
261  return false;
262 
263  if (res->attDescs[i].format == 0)
264  res->binary = 0;
265  }
266 
267  return true;
268 }
269 
270 /*
271  * PQcopyResult
272  *
273  * Returns a deep copy of the provided 'src' PGresult, which cannot be NULL.
274  * The 'flags' argument controls which portions of the result will or will
275  * NOT be copied. The created result is always put into the
276  * PGRES_TUPLES_OK status. The source result error message is not copied,
277  * although cmdStatus is.
278  *
279  * To set custom attributes, use PQsetResultAttrs. That function requires
280  * that there are no attrs contained in the result, so to use that
281  * function you cannot use the PG_COPYRES_ATTRS or PG_COPYRES_TUPLES
282  * options with this function.
283  *
284  * Options:
285  * PG_COPYRES_ATTRS - Copy the source result's attributes
286  *
287  * PG_COPYRES_TUPLES - Copy the source result's tuples. This implies
288  * copying the attrs, seeing how the attrs are needed by the tuples.
289  *
290  * PG_COPYRES_EVENTS - Copy the source result's events.
291  *
292  * PG_COPYRES_NOTICEHOOKS - Copy the source result's notice hooks.
293  */
294 PGresult *
295 PQcopyResult(const PGresult *src, int flags)
296 {
297  PGresult *dest;
298  int i;
299 
300  if (!src)
301  return NULL;
302 
303  dest = PQmakeEmptyPGresult(NULL, PGRES_TUPLES_OK);
304  if (!dest)
305  return NULL;
306 
307  /* Always copy these over. Is cmdStatus really useful here? */
308  dest->client_encoding = src->client_encoding;
309  strcpy(dest->cmdStatus, src->cmdStatus);
310 
311  /* Wants attrs? */
312  if (flags & (PG_COPYRES_ATTRS | PG_COPYRES_TUPLES))
313  {
314  if (!PQsetResultAttrs(dest, src->numAttributes, src->attDescs))
315  {
316  PQclear(dest);
317  return NULL;
318  }
319  }
320 
321  /* Wants to copy tuples? */
322  if (flags & PG_COPYRES_TUPLES)
323  {
324  int tup,
325  field;
326 
327  for (tup = 0; tup < src->ntups; tup++)
328  {
329  for (field = 0; field < src->numAttributes; field++)
330  {
331  if (!PQsetvalue(dest, tup, field,
332  src->tuples[tup][field].value,
333  src->tuples[tup][field].len))
334  {
335  PQclear(dest);
336  return NULL;
337  }
338  }
339  }
340  }
341 
342  /* Wants to copy notice hooks? */
343  if (flags & PG_COPYRES_NOTICEHOOKS)
344  dest->noticeHooks = src->noticeHooks;
345 
346  /* Wants to copy PGEvents? */
347  if ((flags & PG_COPYRES_EVENTS) && src->nEvents > 0)
348  {
349  dest->events = dupEvents(src->events, src->nEvents,
350  &dest->memorySize);
351  if (!dest->events)
352  {
353  PQclear(dest);
354  return NULL;
355  }
356  dest->nEvents = src->nEvents;
357  }
358 
359  /* Okay, trigger PGEVT_RESULTCOPY event */
360  for (i = 0; i < dest->nEvents; i++)
361  {
362  if (src->events[i].resultInitialized)
363  {
364  PGEventResultCopy evt;
365 
366  evt.src = src;
367  evt.dest = dest;
368  if (!dest->events[i].proc(PGEVT_RESULTCOPY, &evt,
369  dest->events[i].passThrough))
370  {
371  PQclear(dest);
372  return NULL;
373  }
374  dest->events[i].resultInitialized = true;
375  }
376  }
377 
378  return dest;
379 }
380 
381 /*
382  * Copy an array of PGEvents (with no extra space for more).
383  * Does not duplicate the event instance data, sets this to NULL.
384  * Also, the resultInitialized flags are all cleared.
385  * The total space allocated is added to *memSize.
386  */
387 static PGEvent *
388 dupEvents(PGEvent *events, int count, size_t *memSize)
389 {
390  PGEvent *newEvents;
391  size_t msize;
392  int i;
393 
394  if (!events || count <= 0)
395  return NULL;
396 
397  msize = count * sizeof(PGEvent);
398  newEvents = (PGEvent *) malloc(msize);
399  if (!newEvents)
400  return NULL;
401 
402  for (i = 0; i < count; i++)
403  {
404  newEvents[i].proc = events[i].proc;
405  newEvents[i].passThrough = events[i].passThrough;
406  newEvents[i].data = NULL;
407  newEvents[i].resultInitialized = false;
408  newEvents[i].name = strdup(events[i].name);
409  if (!newEvents[i].name)
410  {
411  while (--i >= 0)
412  free(newEvents[i].name);
413  free(newEvents);
414  return NULL;
415  }
416  msize += strlen(events[i].name) + 1;
417  }
418 
419  *memSize += msize;
420  return newEvents;
421 }
422 
423 
424 /*
425  * Sets the value for a tuple field. The tup_num must be less than or
426  * equal to PQntuples(res). If it is equal, a new tuple is created and
427  * added to the result.
428  * Returns a non-zero value for success and zero for failure.
429  * (On failure, we report the specific problem via pqInternalNotice.)
430  */
431 int
432 PQsetvalue(PGresult *res, int tup_num, int field_num, char *value, int len)
433 {
434  PGresAttValue *attval;
435  const char *errmsg = NULL;
436 
437  /* Note that this check also protects us against null "res" */
438  if (!check_field_number(res, field_num))
439  return false;
440 
441  /* Invalid tup_num, must be <= ntups */
442  if (tup_num < 0 || tup_num > res->ntups)
443  {
445  "row number %d is out of range 0..%d",
446  tup_num, res->ntups);
447  return false;
448  }
449 
450  /* need to allocate a new tuple? */
451  if (tup_num == res->ntups)
452  {
453  PGresAttValue *tup;
454  int i;
455 
456  tup = (PGresAttValue *)
457  pqResultAlloc(res, res->numAttributes * sizeof(PGresAttValue),
458  true);
459 
460  if (!tup)
461  goto fail;
462 
463  /* initialize each column to NULL */
464  for (i = 0; i < res->numAttributes; i++)
465  {
466  tup[i].len = NULL_LEN;
467  tup[i].value = res->null_field;
468  }
469 
470  /* add it to the array */
471  if (!pqAddTuple(res, tup, &errmsg))
472  goto fail;
473  }
474 
475  attval = &res->tuples[tup_num][field_num];
476 
477  /* treat either NULL_LEN or NULL value pointer as a NULL field */
478  if (len == NULL_LEN || value == NULL)
479  {
480  attval->len = NULL_LEN;
481  attval->value = res->null_field;
482  }
483  else if (len <= 0)
484  {
485  attval->len = 0;
486  attval->value = res->null_field;
487  }
488  else
489  {
490  attval->value = (char *) pqResultAlloc(res, len + 1, true);
491  if (!attval->value)
492  goto fail;
493  attval->len = len;
494  memcpy(attval->value, value, len);
495  attval->value[len] = '\0';
496  }
497 
498  return true;
499 
500  /*
501  * Report failure via pqInternalNotice. If preceding code didn't provide
502  * an error message, assume "out of memory" was meant.
503  */
504 fail:
505  if (!errmsg)
506  errmsg = libpq_gettext("out of memory");
507  pqInternalNotice(&res->noticeHooks, "%s", errmsg);
508 
509  return false;
510 }
511 
512 /*
513  * pqResultAlloc - exported routine to allocate local storage in a PGresult.
514  *
515  * We force all such allocations to be maxaligned, since we don't know
516  * whether the value might be binary.
517  */
518 void *
519 PQresultAlloc(PGresult *res, size_t nBytes)
520 {
521  return pqResultAlloc(res, nBytes, true);
522 }
523 
524 /*
525  * pqResultAlloc -
526  * Allocate subsidiary storage for a PGresult.
527  *
528  * nBytes is the amount of space needed for the object.
529  * If isBinary is true, we assume that we need to align the object on
530  * a machine allocation boundary.
531  * If isBinary is false, we assume the object is a char string and can
532  * be allocated on any byte boundary.
533  */
534 void *
535 pqResultAlloc(PGresult *res, size_t nBytes, bool isBinary)
536 {
537  char *space;
538  PGresult_data *block;
539 
540  if (!res)
541  return NULL;
542 
543  if (nBytes <= 0)
544  return res->null_field;
545 
546  /*
547  * If alignment is needed, round up the current position to an alignment
548  * boundary.
549  */
550  if (isBinary)
551  {
552  int offset = res->curOffset % PGRESULT_ALIGN_BOUNDARY;
553 
554  if (offset)
555  {
556  res->curOffset += PGRESULT_ALIGN_BOUNDARY - offset;
557  res->spaceLeft -= PGRESULT_ALIGN_BOUNDARY - offset;
558  }
559  }
560 
561  /* If there's enough space in the current block, no problem. */
562  if (nBytes <= (size_t) res->spaceLeft)
563  {
564  space = res->curBlock->space + res->curOffset;
565  res->curOffset += nBytes;
566  res->spaceLeft -= nBytes;
567  return space;
568  }
569 
570  /*
571  * If the requested object is very large, give it its own block; this
572  * avoids wasting what might be most of the current block to start a new
573  * block. (We'd have to special-case requests bigger than the block size
574  * anyway.) The object is always given binary alignment in this case.
575  */
576  if (nBytes >= PGRESULT_SEP_ALLOC_THRESHOLD)
577  {
578  size_t alloc_size = nBytes + PGRESULT_BLOCK_OVERHEAD;
579 
580  block = (PGresult_data *) malloc(alloc_size);
581  if (!block)
582  return NULL;
583  res->memorySize += alloc_size;
584  space = block->space + PGRESULT_BLOCK_OVERHEAD;
585  if (res->curBlock)
586  {
587  /*
588  * Tuck special block below the active block, so that we don't
589  * have to waste the free space in the active block.
590  */
591  block->next = res->curBlock->next;
592  res->curBlock->next = block;
593  }
594  else
595  {
596  /* Must set up the new block as the first active block. */
597  block->next = NULL;
598  res->curBlock = block;
599  res->spaceLeft = 0; /* be sure it's marked full */
600  }
601  return space;
602  }
603 
604  /* Otherwise, start a new block. */
606  if (!block)
607  return NULL;
609  block->next = res->curBlock;
610  res->curBlock = block;
611  if (isBinary)
612  {
613  /* object needs full alignment */
616  }
617  else
618  {
619  /* we can cram it right after the overhead pointer */
620  res->curOffset = sizeof(PGresult_data);
622  }
623 
624  space = block->space + res->curOffset;
625  res->curOffset += nBytes;
626  res->spaceLeft -= nBytes;
627  return space;
628 }
629 
630 /*
631  * PQresultMemorySize -
632  * Returns total space allocated for the PGresult.
633  */
634 size_t
636 {
637  if (!res)
638  return 0;
639  return res->memorySize;
640 }
641 
642 /*
643  * pqResultStrdup -
644  * Like strdup, but the space is subsidiary PGresult space.
645  */
646 char *
647 pqResultStrdup(PGresult *res, const char *str)
648 {
649  char *space = (char *) pqResultAlloc(res, strlen(str) + 1, false);
650 
651  if (space)
652  strcpy(space, str);
653  return space;
654 }
655 
656 /*
657  * pqSetResultError -
658  * assign a new error message to a PGresult
659  */
660 void
661 pqSetResultError(PGresult *res, const char *msg)
662 {
663  if (!res)
664  return;
665  if (msg && *msg)
666  res->errMsg = pqResultStrdup(res, msg);
667  else
668  res->errMsg = NULL;
669 }
670 
671 /*
672  * pqCatenateResultError -
673  * concatenate a new error message to the one already in a PGresult
674  */
675 void
676 pqCatenateResultError(PGresult *res, const char *msg)
677 {
678  PQExpBufferData errorBuf;
679 
680  if (!res || !msg)
681  return;
682  initPQExpBuffer(&errorBuf);
683  if (res->errMsg)
684  appendPQExpBufferStr(&errorBuf, res->errMsg);
685  appendPQExpBufferStr(&errorBuf, msg);
686  pqSetResultError(res, errorBuf.data);
687  termPQExpBuffer(&errorBuf);
688 }
689 
690 /*
691  * PQclear -
692  * free's the memory associated with a PGresult
693  */
694 void
696 {
697  PGresult_data *block;
698  int i;
699 
700  if (!res)
701  return;
702 
703  for (i = 0; i < res->nEvents; i++)
704  {
705  /* only send DESTROY to successfully-initialized event procs */
706  if (res->events[i].resultInitialized)
707  {
709 
710  evt.result = res;
711  (void) res->events[i].proc(PGEVT_RESULTDESTROY, &evt,
712  res->events[i].passThrough);
713  }
714  free(res->events[i].name);
715  }
716 
717  if (res->events)
718  free(res->events);
719 
720  /* Free all the subsidiary blocks */
721  while ((block = res->curBlock) != NULL)
722  {
723  res->curBlock = block->next;
724  free(block);
725  }
726 
727  /* Free the top-level tuple pointer array */
728  if (res->tuples)
729  free(res->tuples);
730 
731  /* zero out the pointer fields to catch programming errors */
732  res->attDescs = NULL;
733  res->tuples = NULL;
734  res->paramDescs = NULL;
735  res->errFields = NULL;
736  res->events = NULL;
737  res->nEvents = 0;
738  /* res->curBlock was zeroed out earlier */
739 
740  /* Free the PGresult structure itself */
741  free(res);
742 }
743 
744 /*
745  * Handy subroutine to deallocate any partially constructed async result.
746  *
747  * Any "next" result gets cleared too.
748  */
749 void
751 {
752  if (conn->result)
753  PQclear(conn->result);
754  conn->result = NULL;
755  if (conn->next_result)
756  PQclear(conn->next_result);
757  conn->next_result = NULL;
758 }
759 
760 /*
761  * This subroutine deletes any existing async result, sets conn->result
762  * to a PGresult with status PGRES_FATAL_ERROR, and stores the current
763  * contents of conn->errorMessage into that result. It differs from a
764  * plain call on PQmakeEmptyPGresult() in that if there is already an
765  * async result with status PGRES_FATAL_ERROR, the current error message
766  * is APPENDED to the old error message instead of replacing it. This
767  * behavior lets us report multiple error conditions properly, if necessary.
768  * (An example where this is needed is when the backend sends an 'E' message
769  * and immediately closes the connection --- we want to report both the
770  * backend error and the connection closure error.)
771  */
772 void
774 {
775  /*
776  * If no old async result, just let PQmakeEmptyPGresult make one. Likewise
777  * if old result is not an error message.
778  */
779  if (conn->result == NULL ||
781  conn->result->errMsg == NULL)
782  {
783  pqClearAsyncResult(conn);
785  }
786  else
787  {
788  /* Else, concatenate error message to existing async result. */
790  }
791 }
792 
793 /*
794  * As above, and append conn->write_err_msg to whatever other error we have.
795  * This is used when we've detected a write failure and have exhausted our
796  * chances of reporting something else instead.
797  */
798 static void
800 {
801  /*
802  * Ensure conn->result is an error result, and add anything in
803  * conn->errorMessage to it.
804  */
805  pqSaveErrorResult(conn);
806 
807  /*
808  * Now append write_err_msg to that. If it's null because of previous
809  * strdup failure, do what we can. (It's likely our machinations here are
810  * all getting OOM failures as well, but ...)
811  */
812  if (conn->write_err_msg && conn->write_err_msg[0] != '\0')
814  else
816  libpq_gettext("write to server failed\n"));
817 }
818 
819 /*
820  * This subroutine prepares an async result object for return to the caller.
821  * If there is not already an async result object, build an error object
822  * using whatever is in conn->errorMessage. In any case, clear the async
823  * result storage and make sure PQerrorMessage will agree with the result's
824  * error string.
825  */
826 PGresult *
828 {
829  PGresult *res;
830 
831  /*
832  * conn->result is the PGresult to return. If it is NULL (which probably
833  * shouldn't happen) we assume there is an appropriate error message in
834  * conn->errorMessage.
835  */
836  res = conn->result;
837  if (!res)
839  else
840  {
841  /*
842  * Make sure PQerrorMessage agrees with result; it could be different
843  * if we have concatenated messages.
844  */
847  PQresultErrorMessage(res));
848  }
849 
850  /*
851  * Replace conn->result with next_result, if any. In the normal case
852  * there isn't a next result and we're just dropping ownership of the
853  * current result. In single-row mode this restores the situation to what
854  * it was before we created the current single-row result.
855  */
856  conn->result = conn->next_result;
857  conn->next_result = NULL;
858 
859  return res;
860 }
861 
862 /*
863  * pqInternalNotice - produce an internally-generated notice message
864  *
865  * A format string and optional arguments can be passed. Note that we do
866  * libpq_gettext() here, so callers need not.
867  *
868  * The supplied text is taken as primary message (ie., it should not include
869  * a trailing newline, and should not be more than one line).
870  */
871 void
872 pqInternalNotice(const PGNoticeHooks *hooks, const char *fmt,...)
873 {
874  char msgBuf[1024];
875  va_list args;
876  PGresult *res;
877 
878  if (hooks->noticeRec == NULL)
879  return; /* nobody home to receive notice? */
880 
881  /* Format the message */
882  va_start(args, fmt);
883  vsnprintf(msgBuf, sizeof(msgBuf), libpq_gettext(fmt), args);
884  va_end(args);
885  msgBuf[sizeof(msgBuf) - 1] = '\0'; /* make real sure it's terminated */
886 
887  /* Make a PGresult to pass to the notice receiver */
889  if (!res)
890  return;
891  res->noticeHooks = *hooks;
892 
893  /*
894  * Set up fields of notice.
895  */
899  /* XXX should provide a SQLSTATE too? */
900 
901  /*
902  * Result text is always just the primary message + newline. If we can't
903  * allocate it, don't bother invoking the receiver.
904  */
905  res->errMsg = (char *) pqResultAlloc(res, strlen(msgBuf) + 2, false);
906  if (res->errMsg)
907  {
908  sprintf(res->errMsg, "%s\n", msgBuf);
909 
910  /*
911  * Pass to receiver, then free it.
912  */
913  res->noticeHooks.noticeRec(res->noticeHooks.noticeRecArg, res);
914  }
915  PQclear(res);
916 }
917 
918 /*
919  * pqAddTuple
920  * add a row pointer to the PGresult structure, growing it if necessary
921  * Returns true if OK, false if an error prevented adding the row
922  *
923  * On error, *errmsgp can be set to an error string to be returned.
924  * If it is left NULL, the error is presumed to be "out of memory".
925  */
926 static bool
927 pqAddTuple(PGresult *res, PGresAttValue *tup, const char **errmsgp)
928 {
929  if (res->ntups >= res->tupArrSize)
930  {
931  /*
932  * Try to grow the array.
933  *
934  * We can use realloc because shallow copying of the structure is
935  * okay. Note that the first time through, res->tuples is NULL. While
936  * ANSI says that realloc() should act like malloc() in that case,
937  * some old C libraries (like SunOS 4.1.x) coredump instead. On
938  * failure realloc is supposed to return NULL without damaging the
939  * existing allocation. Note that the positions beyond res->ntups are
940  * garbage, not necessarily NULL.
941  */
942  int newSize;
943  PGresAttValue **newTuples;
944 
945  /*
946  * Since we use integers for row numbers, we can't support more than
947  * INT_MAX rows. Make sure we allow that many, though.
948  */
949  if (res->tupArrSize <= INT_MAX / 2)
950  newSize = (res->tupArrSize > 0) ? res->tupArrSize * 2 : 128;
951  else if (res->tupArrSize < INT_MAX)
952  newSize = INT_MAX;
953  else
954  {
955  *errmsgp = libpq_gettext("PGresult cannot support more than INT_MAX tuples");
956  return false;
957  }
958 
959  /*
960  * Also, on 32-bit platforms we could, in theory, overflow size_t even
961  * before newSize gets to INT_MAX. (In practice we'd doubtless hit
962  * OOM long before that, but let's check.)
963  */
964 #if INT_MAX >= (SIZE_MAX / 2)
965  if (newSize > SIZE_MAX / sizeof(PGresAttValue *))
966  {
967  *errmsgp = libpq_gettext("size_t overflow");
968  return false;
969  }
970 #endif
971 
972  if (res->tuples == NULL)
973  newTuples = (PGresAttValue **)
974  malloc(newSize * sizeof(PGresAttValue *));
975  else
976  newTuples = (PGresAttValue **)
977  realloc(res->tuples, newSize * sizeof(PGresAttValue *));
978  if (!newTuples)
979  return false; /* malloc or realloc failed */
980  res->memorySize +=
981  (newSize - res->tupArrSize) * sizeof(PGresAttValue *);
982  res->tupArrSize = newSize;
983  res->tuples = newTuples;
984  }
985  res->tuples[res->ntups] = tup;
986  res->ntups++;
987  return true;
988 }
989 
990 /*
991  * pqSaveMessageField - save one field of an error or notice message
992  */
993 void
994 pqSaveMessageField(PGresult *res, char code, const char *value)
995 {
996  PGMessageField *pfield;
997 
998  pfield = (PGMessageField *)
999  pqResultAlloc(res,
1000  offsetof(PGMessageField, contents) +
1001  strlen(value) + 1,
1002  true);
1003  if (!pfield)
1004  return; /* out of memory? */
1005  pfield->code = code;
1006  strcpy(pfield->contents, value);
1007  pfield->next = res->errFields;
1008  res->errFields = pfield;
1009 }
1010 
1011 /*
1012  * pqSaveParameterStatus - remember parameter status sent by backend
1013  */
1014 void
1015 pqSaveParameterStatus(PGconn *conn, const char *name, const char *value)
1016 {
1017  pgParameterStatus *pstatus;
1018  pgParameterStatus *prev;
1019 
1020  if (conn->Pfdebug)
1021  fprintf(conn->Pfdebug, "pqSaveParameterStatus: '%s' = '%s'\n",
1022  name, value);
1023 
1024  /*
1025  * Forget any old information about the parameter
1026  */
1027  for (pstatus = conn->pstatus, prev = NULL;
1028  pstatus != NULL;
1029  prev = pstatus, pstatus = pstatus->next)
1030  {
1031  if (strcmp(pstatus->name, name) == 0)
1032  {
1033  if (prev)
1034  prev->next = pstatus->next;
1035  else
1036  conn->pstatus = pstatus->next;
1037  free(pstatus); /* frees name and value strings too */
1038  break;
1039  }
1040  }
1041 
1042  /*
1043  * Store new info as a single malloc block
1044  */
1045  pstatus = (pgParameterStatus *) malloc(sizeof(pgParameterStatus) +
1046  strlen(name) + strlen(value) + 2);
1047  if (pstatus)
1048  {
1049  char *ptr;
1050 
1051  ptr = ((char *) pstatus) + sizeof(pgParameterStatus);
1052  pstatus->name = ptr;
1053  strcpy(ptr, name);
1054  ptr += strlen(name) + 1;
1055  pstatus->value = ptr;
1056  strcpy(ptr, value);
1057  pstatus->next = conn->pstatus;
1058  conn->pstatus = pstatus;
1059  }
1060 
1061  /*
1062  * Special hacks: remember client_encoding and
1063  * standard_conforming_strings, and convert server version to a numeric
1064  * form. We keep the first two of these in static variables as well, so
1065  * that PQescapeString and PQescapeBytea can behave somewhat sanely (at
1066  * least in single-connection-using programs).
1067  */
1068  if (strcmp(name, "client_encoding") == 0)
1069  {
1070  conn->client_encoding = pg_char_to_encoding(value);
1071  /* if we don't recognize the encoding name, fall back to SQL_ASCII */
1072  if (conn->client_encoding < 0)
1073  conn->client_encoding = PG_SQL_ASCII;
1075  }
1076  else if (strcmp(name, "standard_conforming_strings") == 0)
1077  {
1078  conn->std_strings = (strcmp(value, "on") == 0);
1080  }
1081  else if (strcmp(name, "server_version") == 0)
1082  {
1083  int cnt;
1084  int vmaj,
1085  vmin,
1086  vrev;
1087 
1088  cnt = sscanf(value, "%d.%d.%d", &vmaj, &vmin, &vrev);
1089 
1090  if (cnt == 3)
1091  {
1092  /* old style, e.g. 9.6.1 */
1093  conn->sversion = (100 * vmaj + vmin) * 100 + vrev;
1094  }
1095  else if (cnt == 2)
1096  {
1097  if (vmaj >= 10)
1098  {
1099  /* new style, e.g. 10.1 */
1100  conn->sversion = 100 * 100 * vmaj + vmin;
1101  }
1102  else
1103  {
1104  /* old style without minor version, e.g. 9.6devel */
1105  conn->sversion = (100 * vmaj + vmin) * 100;
1106  }
1107  }
1108  else if (cnt == 1)
1109  {
1110  /* new style without minor version, e.g. 10devel */
1111  conn->sversion = 100 * 100 * vmaj;
1112  }
1113  else
1114  conn->sversion = 0; /* unknown */
1115  }
1116 }
1117 
1118 
1119 /*
1120  * pqRowProcessor
1121  * Add the received row to the current async result (conn->result).
1122  * Returns 1 if OK, 0 if error occurred.
1123  *
1124  * On error, *errmsgp can be set to an error string to be returned.
1125  * If it is left NULL, the error is presumed to be "out of memory".
1126  *
1127  * In single-row mode, we create a new result holding just the current row,
1128  * stashing the previous result in conn->next_result so that it becomes
1129  * active again after pqPrepareAsyncResult(). This allows the result metadata
1130  * (column descriptions) to be carried forward to each result row.
1131  */
1132 int
1133 pqRowProcessor(PGconn *conn, const char **errmsgp)
1134 {
1135  PGresult *res = conn->result;
1136  int nfields = res->numAttributes;
1137  const PGdataValue *columns = conn->rowBuf;
1138  PGresAttValue *tup;
1139  int i;
1140 
1141  /*
1142  * In single-row mode, make a new PGresult that will hold just this one
1143  * row; the original conn->result is left unchanged so that it can be used
1144  * again as the template for future rows.
1145  */
1146  if (conn->singleRowMode)
1147  {
1148  /* Copy everything that should be in the result at this point */
1149  res = PQcopyResult(res,
1152  if (!res)
1153  return 0;
1154  }
1155 
1156  /*
1157  * Basically we just allocate space in the PGresult for each field and
1158  * copy the data over.
1159  *
1160  * Note: on malloc failure, we return 0 leaving *errmsgp still NULL, which
1161  * caller will take to mean "out of memory". This is preferable to trying
1162  * to set up such a message here, because evidently there's not enough
1163  * memory for gettext() to do anything.
1164  */
1165  tup = (PGresAttValue *)
1166  pqResultAlloc(res, nfields * sizeof(PGresAttValue), true);
1167  if (tup == NULL)
1168  goto fail;
1169 
1170  for (i = 0; i < nfields; i++)
1171  {
1172  int clen = columns[i].len;
1173 
1174  if (clen < 0)
1175  {
1176  /* null field */
1177  tup[i].len = NULL_LEN;
1178  tup[i].value = res->null_field;
1179  }
1180  else
1181  {
1182  bool isbinary = (res->attDescs[i].format != 0);
1183  char *val;
1184 
1185  val = (char *) pqResultAlloc(res, clen + 1, isbinary);
1186  if (val == NULL)
1187  goto fail;
1188 
1189  /* copy and zero-terminate the data (even if it's binary) */
1190  memcpy(val, columns[i].value, clen);
1191  val[clen] = '\0';
1192 
1193  tup[i].len = clen;
1194  tup[i].value = val;
1195  }
1196  }
1197 
1198  /* And add the tuple to the PGresult's tuple array */
1199  if (!pqAddTuple(res, tup, errmsgp))
1200  goto fail;
1201 
1202  /*
1203  * Success. In single-row mode, make the result available to the client
1204  * immediately.
1205  */
1206  if (conn->singleRowMode)
1207  {
1208  /* Change result status to special single-row value */
1210  /* Stash old result for re-use later */
1211  conn->next_result = conn->result;
1212  conn->result = res;
1213  /* And mark the result ready to return */
1214  conn->asyncStatus = PGASYNC_READY;
1215  }
1216 
1217  return 1;
1218 
1219 fail:
1220  /* release locally allocated PGresult, if we made one */
1221  if (res != conn->result)
1222  PQclear(res);
1223  return 0;
1224 }
1225 
1226 
1227 /*
1228  * PQsendQuery
1229  * Submit a query, but don't wait for it to finish
1230  *
1231  * Returns: 1 if successfully submitted
1232  * 0 if error (conn->errorMessage is set)
1233  */
1234 int
1235 PQsendQuery(PGconn *conn, const char *query)
1236 {
1237  if (!PQsendQueryStart(conn))
1238  return 0;
1239 
1240  /* check the argument */
1241  if (!query)
1242  {
1244  libpq_gettext("command string is a null pointer\n"));
1245  return 0;
1246  }
1247 
1248  /* construct the outgoing Query message */
1249  if (pqPutMsgStart('Q', false, conn) < 0 ||
1250  pqPuts(query, conn) < 0 ||
1251  pqPutMsgEnd(conn) < 0)
1252  {
1253  /* error message should be set up already */
1254  return 0;
1255  }
1256 
1257  /* remember we are using simple query protocol */
1258  conn->queryclass = PGQUERY_SIMPLE;
1259 
1260  /* and remember the query text too, if possible */
1261  /* if insufficient memory, last_query just winds up NULL */
1262  if (conn->last_query)
1263  free(conn->last_query);
1264  conn->last_query = strdup(query);
1265 
1266  /*
1267  * Give the data a push. In nonblock mode, don't complain if we're unable
1268  * to send it all; PQgetResult() will do any additional flushing needed.
1269  */
1270  if (pqFlush(conn) < 0)
1271  {
1272  /* error message should be set up already */
1273  return 0;
1274  }
1275 
1276  /* OK, it's launched! */
1277  conn->asyncStatus = PGASYNC_BUSY;
1278  return 1;
1279 }
1280 
1281 /*
1282  * PQsendQueryParams
1283  * Like PQsendQuery, but use protocol 3.0 so we can pass parameters
1284  */
1285 int
1287  const char *command,
1288  int nParams,
1289  const Oid *paramTypes,
1290  const char *const *paramValues,
1291  const int *paramLengths,
1292  const int *paramFormats,
1293  int resultFormat)
1294 {
1295  if (!PQsendQueryStart(conn))
1296  return 0;
1297 
1298  /* check the arguments */
1299  if (!command)
1300  {
1302  libpq_gettext("command string is a null pointer\n"));
1303  return 0;
1304  }
1305  if (nParams < 0 || nParams > 65535)
1306  {
1308  libpq_gettext("number of parameters must be between 0 and 65535\n"));
1309  return 0;
1310  }
1311 
1312  return PQsendQueryGuts(conn,
1313  command,
1314  "", /* use unnamed statement */
1315  nParams,
1316  paramTypes,
1317  paramValues,
1318  paramLengths,
1319  paramFormats,
1320  resultFormat);
1321 }
1322 
1323 /*
1324  * PQsendPrepare
1325  * Submit a Parse message, but don't wait for it to finish
1326  *
1327  * Returns: 1 if successfully submitted
1328  * 0 if error (conn->errorMessage is set)
1329  */
1330 int
1332  const char *stmtName, const char *query,
1333  int nParams, const Oid *paramTypes)
1334 {
1335  if (!PQsendQueryStart(conn))
1336  return 0;
1337 
1338  /* check the arguments */
1339  if (!stmtName)
1340  {
1342  libpq_gettext("statement name is a null pointer\n"));
1343  return 0;
1344  }
1345  if (!query)
1346  {
1348  libpq_gettext("command string is a null pointer\n"));
1349  return 0;
1350  }
1351  if (nParams < 0 || nParams > 65535)
1352  {
1354  libpq_gettext("number of parameters must be between 0 and 65535\n"));
1355  return 0;
1356  }
1357 
1358  /* This isn't gonna work on a 2.0 server */
1359  if (PG_PROTOCOL_MAJOR(conn->pversion) < 3)
1360  {
1362  libpq_gettext("function requires at least protocol version 3.0\n"));
1363  return 0;
1364  }
1365 
1366  /* construct the Parse message */
1367  if (pqPutMsgStart('P', false, conn) < 0 ||
1368  pqPuts(stmtName, conn) < 0 ||
1369  pqPuts(query, conn) < 0)
1370  goto sendFailed;
1371 
1372  if (nParams > 0 && paramTypes)
1373  {
1374  int i;
1375 
1376  if (pqPutInt(nParams, 2, conn) < 0)
1377  goto sendFailed;
1378  for (i = 0; i < nParams; i++)
1379  {
1380  if (pqPutInt(paramTypes[i], 4, conn) < 0)
1381  goto sendFailed;
1382  }
1383  }
1384  else
1385  {
1386  if (pqPutInt(0, 2, conn) < 0)
1387  goto sendFailed;
1388  }
1389  if (pqPutMsgEnd(conn) < 0)
1390  goto sendFailed;
1391 
1392  /* construct the Sync message */
1393  if (pqPutMsgStart('S', false, conn) < 0 ||
1394  pqPutMsgEnd(conn) < 0)
1395  goto sendFailed;
1396 
1397  /* remember we are doing just a Parse */
1398  conn->queryclass = PGQUERY_PREPARE;
1399 
1400  /* and remember the query text too, if possible */
1401  /* if insufficient memory, last_query just winds up NULL */
1402  if (conn->last_query)
1403  free(conn->last_query);
1404  conn->last_query = strdup(query);
1405 
1406  /*
1407  * Give the data a push. In nonblock mode, don't complain if we're unable
1408  * to send it all; PQgetResult() will do any additional flushing needed.
1409  */
1410  if (pqFlush(conn) < 0)
1411  goto sendFailed;
1412 
1413  /* OK, it's launched! */
1414  conn->asyncStatus = PGASYNC_BUSY;
1415  return 1;
1416 
1417 sendFailed:
1418  /* error message should be set up already */
1419  return 0;
1420 }
1421 
1422 /*
1423  * PQsendQueryPrepared
1424  * Like PQsendQuery, but execute a previously prepared statement,
1425  * using protocol 3.0 so we can pass parameters
1426  */
1427 int
1429  const char *stmtName,
1430  int nParams,
1431  const char *const *paramValues,
1432  const int *paramLengths,
1433  const int *paramFormats,
1434  int resultFormat)
1435 {
1436  if (!PQsendQueryStart(conn))
1437  return 0;
1438 
1439  /* check the arguments */
1440  if (!stmtName)
1441  {
1443  libpq_gettext("statement name is a null pointer\n"));
1444  return 0;
1445  }
1446  if (nParams < 0 || nParams > 65535)
1447  {
1449  libpq_gettext("number of parameters must be between 0 and 65535\n"));
1450  return 0;
1451  }
1452 
1453  return PQsendQueryGuts(conn,
1454  NULL, /* no command to parse */
1455  stmtName,
1456  nParams,
1457  NULL, /* no param types */
1458  paramValues,
1459  paramLengths,
1460  paramFormats,
1461  resultFormat);
1462 }
1463 
1464 /*
1465  * Common startup code for PQsendQuery and sibling routines
1466  */
1467 static bool
1469 {
1470  if (!conn)
1471  return false;
1472 
1473  /* clear the error string */
1475 
1476  /* Don't try to send if we know there's no live connection. */
1477  if (conn->status != CONNECTION_OK)
1478  {
1480  libpq_gettext("no connection to the server\n"));
1481  return false;
1482  }
1483  /* Can't send while already busy, either. */
1484  if (conn->asyncStatus != PGASYNC_IDLE)
1485  {
1487  libpq_gettext("another command is already in progress\n"));
1488  return false;
1489  }
1490 
1491  /* initialize async result-accumulation state */
1492  pqClearAsyncResult(conn);
1493 
1494  /* reset single-row processing mode */
1495  conn->singleRowMode = false;
1496 
1497  /* ready to send command message */
1498  return true;
1499 }
1500 
1501 /*
1502  * PQsendQueryGuts
1503  * Common code for protocol-3.0 query sending
1504  * PQsendQueryStart should be done already
1505  *
1506  * command may be NULL to indicate we use an already-prepared statement
1507  */
1508 static int
1510  const char *command,
1511  const char *stmtName,
1512  int nParams,
1513  const Oid *paramTypes,
1514  const char *const *paramValues,
1515  const int *paramLengths,
1516  const int *paramFormats,
1517  int resultFormat)
1518 {
1519  int i;
1520 
1521  /* This isn't gonna work on a 2.0 server */
1522  if (PG_PROTOCOL_MAJOR(conn->pversion) < 3)
1523  {
1525  libpq_gettext("function requires at least protocol version 3.0\n"));
1526  return 0;
1527  }
1528 
1529  /*
1530  * We will send Parse (if needed), Bind, Describe Portal, Execute, Sync,
1531  * using specified statement name and the unnamed portal.
1532  */
1533 
1534  if (command)
1535  {
1536  /* construct the Parse message */
1537  if (pqPutMsgStart('P', false, conn) < 0 ||
1538  pqPuts(stmtName, conn) < 0 ||
1539  pqPuts(command, conn) < 0)
1540  goto sendFailed;
1541  if (nParams > 0 && paramTypes)
1542  {
1543  if (pqPutInt(nParams, 2, conn) < 0)
1544  goto sendFailed;
1545  for (i = 0; i < nParams; i++)
1546  {
1547  if (pqPutInt(paramTypes[i], 4, conn) < 0)
1548  goto sendFailed;
1549  }
1550  }
1551  else
1552  {
1553  if (pqPutInt(0, 2, conn) < 0)
1554  goto sendFailed;
1555  }
1556  if (pqPutMsgEnd(conn) < 0)
1557  goto sendFailed;
1558  }
1559 
1560  /* Construct the Bind message */
1561  if (pqPutMsgStart('B', false, conn) < 0 ||
1562  pqPuts("", conn) < 0 ||
1563  pqPuts(stmtName, conn) < 0)
1564  goto sendFailed;
1565 
1566  /* Send parameter formats */
1567  if (nParams > 0 && paramFormats)
1568  {
1569  if (pqPutInt(nParams, 2, conn) < 0)
1570  goto sendFailed;
1571  for (i = 0; i < nParams; i++)
1572  {
1573  if (pqPutInt(paramFormats[i], 2, conn) < 0)
1574  goto sendFailed;
1575  }
1576  }
1577  else
1578  {
1579  if (pqPutInt(0, 2, conn) < 0)
1580  goto sendFailed;
1581  }
1582 
1583  if (pqPutInt(nParams, 2, conn) < 0)
1584  goto sendFailed;
1585 
1586  /* Send parameters */
1587  for (i = 0; i < nParams; i++)
1588  {
1589  if (paramValues && paramValues[i])
1590  {
1591  int nbytes;
1592 
1593  if (paramFormats && paramFormats[i] != 0)
1594  {
1595  /* binary parameter */
1596  if (paramLengths)
1597  nbytes = paramLengths[i];
1598  else
1599  {
1601  libpq_gettext("length must be given for binary parameter\n"));
1602  goto sendFailed;
1603  }
1604  }
1605  else
1606  {
1607  /* text parameter, do not use paramLengths */
1608  nbytes = strlen(paramValues[i]);
1609  }
1610  if (pqPutInt(nbytes, 4, conn) < 0 ||
1611  pqPutnchar(paramValues[i], nbytes, conn) < 0)
1612  goto sendFailed;
1613  }
1614  else
1615  {
1616  /* take the param as NULL */
1617  if (pqPutInt(-1, 4, conn) < 0)
1618  goto sendFailed;
1619  }
1620  }
1621  if (pqPutInt(1, 2, conn) < 0 ||
1622  pqPutInt(resultFormat, 2, conn))
1623  goto sendFailed;
1624  if (pqPutMsgEnd(conn) < 0)
1625  goto sendFailed;
1626 
1627  /* construct the Describe Portal message */
1628  if (pqPutMsgStart('D', false, conn) < 0 ||
1629  pqPutc('P', conn) < 0 ||
1630  pqPuts("", conn) < 0 ||
1631  pqPutMsgEnd(conn) < 0)
1632  goto sendFailed;
1633 
1634  /* construct the Execute message */
1635  if (pqPutMsgStart('E', false, conn) < 0 ||
1636  pqPuts("", conn) < 0 ||
1637  pqPutInt(0, 4, conn) < 0 ||
1638  pqPutMsgEnd(conn) < 0)
1639  goto sendFailed;
1640 
1641  /* construct the Sync message */
1642  if (pqPutMsgStart('S', false, conn) < 0 ||
1643  pqPutMsgEnd(conn) < 0)
1644  goto sendFailed;
1645 
1646  /* remember we are using extended query protocol */
1647  conn->queryclass = PGQUERY_EXTENDED;
1648 
1649  /* and remember the query text too, if possible */
1650  /* if insufficient memory, last_query just winds up NULL */
1651  if (conn->last_query)
1652  free(conn->last_query);
1653  if (command)
1654  conn->last_query = strdup(command);
1655  else
1656  conn->last_query = NULL;
1657 
1658  /*
1659  * Give the data a push. In nonblock mode, don't complain if we're unable
1660  * to send it all; PQgetResult() will do any additional flushing needed.
1661  */
1662  if (pqFlush(conn) < 0)
1663  goto sendFailed;
1664 
1665  /* OK, it's launched! */
1666  conn->asyncStatus = PGASYNC_BUSY;
1667  return 1;
1668 
1669 sendFailed:
1670  /* error message should be set up already */
1671  return 0;
1672 }
1673 
1674 /*
1675  * Select row-by-row processing mode
1676  */
1677 int
1679 {
1680  /*
1681  * Only allow setting the flag when we have launched a query and not yet
1682  * received any results.
1683  */
1684  if (!conn)
1685  return 0;
1686  if (conn->asyncStatus != PGASYNC_BUSY)
1687  return 0;
1688  if (conn->queryclass != PGQUERY_SIMPLE &&
1689  conn->queryclass != PGQUERY_EXTENDED)
1690  return 0;
1691  if (conn->result)
1692  return 0;
1693 
1694  /* OK, set flag */
1695  conn->singleRowMode = true;
1696  return 1;
1697 }
1698 
1699 /*
1700  * Consume any available input from the backend
1701  * 0 return: some kind of trouble
1702  * 1 return: no problem
1703  */
1704 int
1706 {
1707  if (!conn)
1708  return 0;
1709 
1710  /*
1711  * for non-blocking connections try to flush the send-queue, otherwise we
1712  * may never get a response for something that may not have already been
1713  * sent because it's in our write buffer!
1714  */
1715  if (pqIsnonblocking(conn))
1716  {
1717  if (pqFlush(conn) < 0)
1718  return 0;
1719  }
1720 
1721  /*
1722  * Load more data, if available. We do this no matter what state we are
1723  * in, since we are probably getting called because the application wants
1724  * to get rid of a read-select condition. Note that we will NOT block
1725  * waiting for more input.
1726  */
1727  if (pqReadData(conn) < 0)
1728  return 0;
1729 
1730  /* Parsing of the data waits till later. */
1731  return 1;
1732 }
1733 
1734 
1735 /*
1736  * parseInput: if appropriate, parse input data from backend
1737  * until input is exhausted or a stopping state is reached.
1738  * Note that this function will NOT attempt to read more data from the backend.
1739  */
1740 static void
1742 {
1743  if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
1744  pqParseInput3(conn);
1745  else
1746  pqParseInput2(conn);
1747 }
1748 
1749 /*
1750  * PQisBusy
1751  * Return true if PQgetResult would block waiting for input.
1752  */
1753 
1754 int
1756 {
1757  if (!conn)
1758  return false;
1759 
1760  /* Parse any available data, if our state permits. */
1761  parseInput(conn);
1762 
1763  /*
1764  * PQgetResult will return immediately in all states except BUSY, or if we
1765  * had a write failure.
1766  */
1767  return conn->asyncStatus == PGASYNC_BUSY || conn->write_failed;
1768 }
1769 
1770 
1771 /*
1772  * PQgetResult
1773  * Get the next PGresult produced by a query. Returns NULL if no
1774  * query work remains or an error has occurred (e.g. out of
1775  * memory).
1776  */
1777 
1778 PGresult *
1780 {
1781  PGresult *res;
1782 
1783  if (!conn)
1784  return NULL;
1785 
1786  /* Parse any available data, if our state permits. */
1787  parseInput(conn);
1788 
1789  /* If not ready to return something, block until we are. */
1790  while (conn->asyncStatus == PGASYNC_BUSY)
1791  {
1792  int flushResult;
1793 
1794  /*
1795  * If data remains unsent, send it. Else we might be waiting for the
1796  * result of a command the backend hasn't even got yet.
1797  */
1798  while ((flushResult = pqFlush(conn)) > 0)
1799  {
1800  if (pqWait(false, true, conn))
1801  {
1802  flushResult = -1;
1803  break;
1804  }
1805  }
1806 
1807  /*
1808  * Wait for some more data, and load it. (Note: if the connection has
1809  * been lost, pqWait should return immediately because the socket
1810  * should be read-ready, either with the last server data or with an
1811  * EOF indication. We expect therefore that this won't result in any
1812  * undue delay in reporting a previous write failure.)
1813  */
1814  if (flushResult ||
1815  pqWait(true, false, conn) ||
1816  pqReadData(conn) < 0)
1817  {
1818  /*
1819  * conn->errorMessage has been set by pqWait or pqReadData. We
1820  * want to append it to any already-received error message.
1821  */
1822  pqSaveErrorResult(conn);
1823  conn->asyncStatus = PGASYNC_IDLE;
1824  return pqPrepareAsyncResult(conn);
1825  }
1826 
1827  /* Parse it. */
1828  parseInput(conn);
1829 
1830  /*
1831  * If we had a write error, but nothing above obtained a query result
1832  * or detected a read error, report the write error.
1833  */
1834  if (conn->write_failed && conn->asyncStatus == PGASYNC_BUSY)
1835  {
1836  pqSaveWriteError(conn);
1837  conn->asyncStatus = PGASYNC_IDLE;
1838  return pqPrepareAsyncResult(conn);
1839  }
1840  }
1841 
1842  /* Return the appropriate thing. */
1843  switch (conn->asyncStatus)
1844  {
1845  case PGASYNC_IDLE:
1846  res = NULL; /* query is complete */
1847  break;
1848  case PGASYNC_READY:
1849  res = pqPrepareAsyncResult(conn);
1850  /* Set the state back to BUSY, allowing parsing to proceed. */
1851  conn->asyncStatus = PGASYNC_BUSY;
1852  break;
1853  case PGASYNC_COPY_IN:
1854  res = getCopyResult(conn, PGRES_COPY_IN);
1855  break;
1856  case PGASYNC_COPY_OUT:
1857  res = getCopyResult(conn, PGRES_COPY_OUT);
1858  break;
1859  case PGASYNC_COPY_BOTH:
1860  res = getCopyResult(conn, PGRES_COPY_BOTH);
1861  break;
1862  default:
1864  libpq_gettext("unexpected asyncStatus: %d\n"),
1865  (int) conn->asyncStatus);
1867  break;
1868  }
1869 
1870  if (res)
1871  {
1872  int i;
1873 
1874  for (i = 0; i < res->nEvents; i++)
1875  {
1876  PGEventResultCreate evt;
1877 
1878  evt.conn = conn;
1879  evt.result = res;
1880  if (!res->events[i].proc(PGEVT_RESULTCREATE, &evt,
1881  res->events[i].passThrough))
1882  {
1884  libpq_gettext("PGEventProc \"%s\" failed during PGEVT_RESULTCREATE event\n"),
1885  res->events[i].name);
1886  pqSetResultError(res, conn->errorMessage.data);
1888  break;
1889  }
1890  res->events[i].resultInitialized = true;
1891  }
1892  }
1893 
1894  return res;
1895 }
1896 
1897 /*
1898  * getCopyResult
1899  * Helper for PQgetResult: generate result for COPY-in-progress cases
1900  */
1901 static PGresult *
1903 {
1904  /*
1905  * If the server connection has been lost, don't pretend everything is
1906  * hunky-dory; instead return a PGRES_FATAL_ERROR result, and reset the
1907  * asyncStatus to idle (corresponding to what we'd do if we'd detected I/O
1908  * error in the earlier steps in PQgetResult). The text returned in the
1909  * result is whatever is in conn->errorMessage; we hope that was filled
1910  * with something relevant when the lost connection was detected.
1911  */
1912  if (conn->status != CONNECTION_OK)
1913  {
1914  pqSaveErrorResult(conn);
1915  conn->asyncStatus = PGASYNC_IDLE;
1916  return pqPrepareAsyncResult(conn);
1917  }
1918 
1919  /* If we have an async result for the COPY, return that */
1920  if (conn->result && conn->result->resultStatus == copytype)
1921  return pqPrepareAsyncResult(conn);
1922 
1923  /* Otherwise, invent a suitable PGresult */
1924  return PQmakeEmptyPGresult(conn, copytype);
1925 }
1926 
1927 
1928 /*
1929  * PQexec
1930  * send a query to the backend and package up the result in a PGresult
1931  *
1932  * If the query was not even sent, return NULL; conn->errorMessage is set to
1933  * a relevant message.
1934  * If the query was sent, a new PGresult is returned (which could indicate
1935  * either success or failure).
1936  * The user is responsible for freeing the PGresult via PQclear()
1937  * when done with it.
1938  */
1939 PGresult *
1940 PQexec(PGconn *conn, const char *query)
1941 {
1942  if (!PQexecStart(conn))
1943  return NULL;
1944  if (!PQsendQuery(conn, query))
1945  return NULL;
1946  return PQexecFinish(conn);
1947 }
1948 
1949 /*
1950  * PQexecParams
1951  * Like PQexec, but use protocol 3.0 so we can pass parameters
1952  */
1953 PGresult *
1955  const char *command,
1956  int nParams,
1957  const Oid *paramTypes,
1958  const char *const *paramValues,
1959  const int *paramLengths,
1960  const int *paramFormats,
1961  int resultFormat)
1962 {
1963  if (!PQexecStart(conn))
1964  return NULL;
1965  if (!PQsendQueryParams(conn, command,
1966  nParams, paramTypes, paramValues, paramLengths,
1967  paramFormats, resultFormat))
1968  return NULL;
1969  return PQexecFinish(conn);
1970 }
1971 
1972 /*
1973  * PQprepare
1974  * Creates a prepared statement by issuing a v3.0 parse message.
1975  *
1976  * If the query was not even sent, return NULL; conn->errorMessage is set to
1977  * a relevant message.
1978  * If the query was sent, a new PGresult is returned (which could indicate
1979  * either success or failure).
1980  * The user is responsible for freeing the PGresult via PQclear()
1981  * when done with it.
1982  */
1983 PGresult *
1985  const char *stmtName, const char *query,
1986  int nParams, const Oid *paramTypes)
1987 {
1988  if (!PQexecStart(conn))
1989  return NULL;
1990  if (!PQsendPrepare(conn, stmtName, query, nParams, paramTypes))
1991  return NULL;
1992  return PQexecFinish(conn);
1993 }
1994 
1995 /*
1996  * PQexecPrepared
1997  * Like PQexec, but execute a previously prepared statement,
1998  * using protocol 3.0 so we can pass parameters
1999  */
2000 PGresult *
2002  const char *stmtName,
2003  int nParams,
2004  const char *const *paramValues,
2005  const int *paramLengths,
2006  const int *paramFormats,
2007  int resultFormat)
2008 {
2009  if (!PQexecStart(conn))
2010  return NULL;
2011  if (!PQsendQueryPrepared(conn, stmtName,
2012  nParams, paramValues, paramLengths,
2013  paramFormats, resultFormat))
2014  return NULL;
2015  return PQexecFinish(conn);
2016 }
2017 
2018 /*
2019  * Common code for PQexec and sibling routines: prepare to send command
2020  */
2021 static bool
2023 {
2024  PGresult *result;
2025 
2026  if (!conn)
2027  return false;
2028 
2029  /*
2030  * Silently discard any prior query result that application didn't eat.
2031  * This is probably poor design, but it's here for backward compatibility.
2032  */
2033  while ((result = PQgetResult(conn)) != NULL)
2034  {
2035  ExecStatusType resultStatus = result->resultStatus;
2036 
2037  PQclear(result); /* only need its status */
2038  if (resultStatus == PGRES_COPY_IN)
2039  {
2040  if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
2041  {
2042  /* In protocol 3, we can get out of a COPY IN state */
2043  if (PQputCopyEnd(conn,
2044  libpq_gettext("COPY terminated by new PQexec")) < 0)
2045  return false;
2046  /* keep waiting to swallow the copy's failure message */
2047  }
2048  else
2049  {
2050  /* In older protocols we have to punt */
2052  libpq_gettext("COPY IN state must be terminated first\n"));
2053  return false;
2054  }
2055  }
2056  else if (resultStatus == PGRES_COPY_OUT)
2057  {
2058  if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
2059  {
2060  /*
2061  * In protocol 3, we can get out of a COPY OUT state: we just
2062  * switch back to BUSY and allow the remaining COPY data to be
2063  * dropped on the floor.
2064  */
2065  conn->asyncStatus = PGASYNC_BUSY;
2066  /* keep waiting to swallow the copy's completion message */
2067  }
2068  else
2069  {
2070  /* In older protocols we have to punt */
2072  libpq_gettext("COPY OUT state must be terminated first\n"));
2073  return false;
2074  }
2075  }
2076  else if (resultStatus == PGRES_COPY_BOTH)
2077  {
2078  /* We don't allow PQexec during COPY BOTH */
2080  libpq_gettext("PQexec not allowed during COPY BOTH\n"));
2081  return false;
2082  }
2083  /* check for loss of connection, too */
2084  if (conn->status == CONNECTION_BAD)
2085  return false;
2086  }
2087 
2088  /* OK to send a command */
2089  return true;
2090 }
2091 
2092 /*
2093  * Common code for PQexec and sibling routines: wait for command result
2094  */
2095 static PGresult *
2097 {
2098  PGresult *result;
2099  PGresult *lastResult;
2100 
2101  /*
2102  * For backwards compatibility, return the last result if there are more
2103  * than one --- but merge error messages if we get more than one error
2104  * result.
2105  *
2106  * We have to stop if we see copy in/out/both, however. We will resume
2107  * parsing after application performs the data transfer.
2108  *
2109  * Also stop if the connection is lost (else we'll loop infinitely).
2110  */
2111  lastResult = NULL;
2112  while ((result = PQgetResult(conn)) != NULL)
2113  {
2114  if (lastResult)
2115  {
2116  if (lastResult->resultStatus == PGRES_FATAL_ERROR &&
2117  result->resultStatus == PGRES_FATAL_ERROR)
2118  {
2119  pqCatenateResultError(lastResult, result->errMsg);
2120  PQclear(result);
2121  result = lastResult;
2122 
2123  /*
2124  * Make sure PQerrorMessage agrees with concatenated result
2125  */
2127  appendPQExpBufferStr(&conn->errorMessage, result->errMsg);
2128  }
2129  else
2130  PQclear(lastResult);
2131  }
2132  lastResult = result;
2133  if (result->resultStatus == PGRES_COPY_IN ||
2134  result->resultStatus == PGRES_COPY_OUT ||
2135  result->resultStatus == PGRES_COPY_BOTH ||
2136  conn->status == CONNECTION_BAD)
2137  break;
2138  }
2139 
2140  return lastResult;
2141 }
2142 
2143 /*
2144  * PQdescribePrepared
2145  * Obtain information about a previously prepared statement
2146  *
2147  * If the query was not even sent, return NULL; conn->errorMessage is set to
2148  * a relevant message.
2149  * If the query was sent, a new PGresult is returned (which could indicate
2150  * either success or failure). On success, the PGresult contains status
2151  * PGRES_COMMAND_OK, and its parameter and column-heading fields describe
2152  * the statement's inputs and outputs respectively.
2153  * The user is responsible for freeing the PGresult via PQclear()
2154  * when done with it.
2155  */
2156 PGresult *
2157 PQdescribePrepared(PGconn *conn, const char *stmt)
2158 {
2159  if (!PQexecStart(conn))
2160  return NULL;
2161  if (!PQsendDescribe(conn, 'S', stmt))
2162  return NULL;
2163  return PQexecFinish(conn);
2164 }
2165 
2166 /*
2167  * PQdescribePortal
2168  * Obtain information about a previously created portal
2169  *
2170  * This is much like PQdescribePrepared, except that no parameter info is
2171  * returned. Note that at the moment, libpq doesn't really expose portals
2172  * to the client; but this can be used with a portal created by a SQL
2173  * DECLARE CURSOR command.
2174  */
2175 PGresult *
2176 PQdescribePortal(PGconn *conn, const char *portal)
2177 {
2178  if (!PQexecStart(conn))
2179  return NULL;
2180  if (!PQsendDescribe(conn, 'P', portal))
2181  return NULL;
2182  return PQexecFinish(conn);
2183 }
2184 
2185 /*
2186  * PQsendDescribePrepared
2187  * Submit a Describe Statement command, but don't wait for it to finish
2188  *
2189  * Returns: 1 if successfully submitted
2190  * 0 if error (conn->errorMessage is set)
2191  */
2192 int
2194 {
2195  return PQsendDescribe(conn, 'S', stmt);
2196 }
2197 
2198 /*
2199  * PQsendDescribePortal
2200  * Submit a Describe Portal command, but don't wait for it to finish
2201  *
2202  * Returns: 1 if successfully submitted
2203  * 0 if error (conn->errorMessage is set)
2204  */
2205 int
2206 PQsendDescribePortal(PGconn *conn, const char *portal)
2207 {
2208  return PQsendDescribe(conn, 'P', portal);
2209 }
2210 
2211 /*
2212  * PQsendDescribe
2213  * Common code to send a Describe command
2214  *
2215  * Available options for desc_type are
2216  * 'S' to describe a prepared statement; or
2217  * 'P' to describe a portal.
2218  * Returns 1 on success and 0 on failure.
2219  */
2220 static int
2221 PQsendDescribe(PGconn *conn, char desc_type, const char *desc_target)
2222 {
2223  /* Treat null desc_target as empty string */
2224  if (!desc_target)
2225  desc_target = "";
2226 
2227  if (!PQsendQueryStart(conn))
2228  return 0;
2229 
2230  /* This isn't gonna work on a 2.0 server */
2231  if (PG_PROTOCOL_MAJOR(conn->pversion) < 3)
2232  {
2234  libpq_gettext("function requires at least protocol version 3.0\n"));
2235  return 0;
2236  }
2237 
2238  /* construct the Describe message */
2239  if (pqPutMsgStart('D', false, conn) < 0 ||
2240  pqPutc(desc_type, conn) < 0 ||
2241  pqPuts(desc_target, conn) < 0 ||
2242  pqPutMsgEnd(conn) < 0)
2243  goto sendFailed;
2244 
2245  /* construct the Sync message */
2246  if (pqPutMsgStart('S', false, conn) < 0 ||
2247  pqPutMsgEnd(conn) < 0)
2248  goto sendFailed;
2249 
2250  /* remember we are doing a Describe */
2251  conn->queryclass = PGQUERY_DESCRIBE;
2252 
2253  /* reset last_query string (not relevant now) */
2254  if (conn->last_query)
2255  {
2256  free(conn->last_query);
2257  conn->last_query = NULL;
2258  }
2259 
2260  /*
2261  * Give the data a push. In nonblock mode, don't complain if we're unable
2262  * to send it all; PQgetResult() will do any additional flushing needed.
2263  */
2264  if (pqFlush(conn) < 0)
2265  goto sendFailed;
2266 
2267  /* OK, it's launched! */
2268  conn->asyncStatus = PGASYNC_BUSY;
2269  return 1;
2270 
2271 sendFailed:
2272  /* error message should be set up already */
2273  return 0;
2274 }
2275 
2276 /*
2277  * PQnotifies
2278  * returns a PGnotify* structure of the latest async notification
2279  * that has not yet been handled
2280  *
2281  * returns NULL, if there is currently
2282  * no unhandled async notification from the backend
2283  *
2284  * the CALLER is responsible for FREE'ing the structure returned
2285  *
2286  * Note that this function does not read any new data from the socket;
2287  * so usually, caller should call PQconsumeInput() first.
2288  */
2289 PGnotify *
2291 {
2292  PGnotify *event;
2293 
2294  if (!conn)
2295  return NULL;
2296 
2297  /* Parse any available data to see if we can extract NOTIFY messages. */
2298  parseInput(conn);
2299 
2300  event = conn->notifyHead;
2301  if (event)
2302  {
2303  conn->notifyHead = event->next;
2304  if (!conn->notifyHead)
2305  conn->notifyTail = NULL;
2306  event->next = NULL; /* don't let app see the internal state */
2307  }
2308  return event;
2309 }
2310 
2311 /*
2312  * PQputCopyData - send some data to the backend during COPY IN or COPY BOTH
2313  *
2314  * Returns 1 if successful, 0 if data could not be sent (only possible
2315  * in nonblock mode), or -1 if an error occurs.
2316  */
2317 int
2318 PQputCopyData(PGconn *conn, const char *buffer, int nbytes)
2319 {
2320  if (!conn)
2321  return -1;
2322  if (conn->asyncStatus != PGASYNC_COPY_IN &&
2323  conn->asyncStatus != PGASYNC_COPY_BOTH)
2324  {
2326  libpq_gettext("no COPY in progress\n"));
2327  return -1;
2328  }
2329 
2330  /*
2331  * Process any NOTICE or NOTIFY messages that might be pending in the
2332  * input buffer. Since the server might generate many notices during the
2333  * COPY, we want to clean those out reasonably promptly to prevent
2334  * indefinite expansion of the input buffer. (Note: the actual read of
2335  * input data into the input buffer happens down inside pqSendSome, but
2336  * it's not authorized to get rid of the data again.)
2337  */
2338  parseInput(conn);
2339 
2340  if (nbytes > 0)
2341  {
2342  /*
2343  * Try to flush any previously sent data in preference to growing the
2344  * output buffer. If we can't enlarge the buffer enough to hold the
2345  * data, return 0 in the nonblock case, else hard error. (For
2346  * simplicity, always assume 5 bytes of overhead even in protocol 2.0
2347  * case.)
2348  */
2349  if ((conn->outBufSize - conn->outCount - 5) < nbytes)
2350  {
2351  if (pqFlush(conn) < 0)
2352  return -1;
2353  if (pqCheckOutBufferSpace(conn->outCount + 5 + (size_t) nbytes,
2354  conn))
2355  return pqIsnonblocking(conn) ? 0 : -1;
2356  }
2357  /* Send the data (too simple to delegate to fe-protocol files) */
2358  if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
2359  {
2360  if (pqPutMsgStart('d', false, conn) < 0 ||
2361  pqPutnchar(buffer, nbytes, conn) < 0 ||
2362  pqPutMsgEnd(conn) < 0)
2363  return -1;
2364  }
2365  else
2366  {
2367  if (pqPutMsgStart(0, false, conn) < 0 ||
2368  pqPutnchar(buffer, nbytes, conn) < 0 ||
2369  pqPutMsgEnd(conn) < 0)
2370  return -1;
2371  }
2372  }
2373  return 1;
2374 }
2375 
2376 /*
2377  * PQputCopyEnd - send EOF indication to the backend during COPY IN
2378  *
2379  * After calling this, use PQgetResult() to check command completion status.
2380  *
2381  * Returns 1 if successful, 0 if data could not be sent (only possible
2382  * in nonblock mode), or -1 if an error occurs.
2383  */
2384 int
2385 PQputCopyEnd(PGconn *conn, const char *errormsg)
2386 {
2387  if (!conn)
2388  return -1;
2389  if (conn->asyncStatus != PGASYNC_COPY_IN &&
2390  conn->asyncStatus != PGASYNC_COPY_BOTH)
2391  {
2393  libpq_gettext("no COPY in progress\n"));
2394  return -1;
2395  }
2396 
2397  /*
2398  * Send the COPY END indicator. This is simple enough that we don't
2399  * bother delegating it to the fe-protocol files.
2400  */
2401  if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
2402  {
2403  if (errormsg)
2404  {
2405  /* Send COPY FAIL */
2406  if (pqPutMsgStart('f', false, conn) < 0 ||
2407  pqPuts(errormsg, conn) < 0 ||
2408  pqPutMsgEnd(conn) < 0)
2409  return -1;
2410  }
2411  else
2412  {
2413  /* Send COPY DONE */
2414  if (pqPutMsgStart('c', false, conn) < 0 ||
2415  pqPutMsgEnd(conn) < 0)
2416  return -1;
2417  }
2418 
2419  /*
2420  * If we sent the COPY command in extended-query mode, we must issue a
2421  * Sync as well.
2422  */
2423  if (conn->queryclass != PGQUERY_SIMPLE)
2424  {
2425  if (pqPutMsgStart('S', false, conn) < 0 ||
2426  pqPutMsgEnd(conn) < 0)
2427  return -1;
2428  }
2429  }
2430  else
2431  {
2432  if (errormsg)
2433  {
2434  /* Oops, no way to do this in 2.0 */
2436  libpq_gettext("function requires at least protocol version 3.0\n"));
2437  return -1;
2438  }
2439  else
2440  {
2441  /* Send old-style end-of-data marker */
2442  if (pqPutMsgStart(0, false, conn) < 0 ||
2443  pqPutnchar("\\.\n", 3, conn) < 0 ||
2444  pqPutMsgEnd(conn) < 0)
2445  return -1;
2446  }
2447  }
2448 
2449  /* Return to active duty */
2450  if (conn->asyncStatus == PGASYNC_COPY_BOTH)
2451  conn->asyncStatus = PGASYNC_COPY_OUT;
2452  else
2453  conn->asyncStatus = PGASYNC_BUSY;
2455 
2456  /* Try to flush data */
2457  if (pqFlush(conn) < 0)
2458  return -1;
2459 
2460  return 1;
2461 }
2462 
2463 /*
2464  * PQgetCopyData - read a row of data from the backend during COPY OUT
2465  * or COPY BOTH
2466  *
2467  * If successful, sets *buffer to point to a malloc'd row of data, and
2468  * returns row length (always > 0) as result.
2469  * Returns 0 if no row available yet (only possible if async is true),
2470  * -1 if end of copy (consult PQgetResult), or -2 if error (consult
2471  * PQerrorMessage).
2472  */
2473 int
2474 PQgetCopyData(PGconn *conn, char **buffer, int async)
2475 {
2476  *buffer = NULL; /* for all failure cases */
2477  if (!conn)
2478  return -2;
2479  if (conn->asyncStatus != PGASYNC_COPY_OUT &&
2480  conn->asyncStatus != PGASYNC_COPY_BOTH)
2481  {
2483  libpq_gettext("no COPY in progress\n"));
2484  return -2;
2485  }
2486  if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
2487  return pqGetCopyData3(conn, buffer, async);
2488  else
2489  return pqGetCopyData2(conn, buffer, async);
2490 }
2491 
2492 /*
2493  * PQgetline - gets a newline-terminated string from the backend.
2494  *
2495  * Chiefly here so that applications can use "COPY <rel> to stdout"
2496  * and read the output string. Returns a null-terminated string in s.
2497  *
2498  * XXX this routine is now deprecated, because it can't handle binary data.
2499  * If called during a COPY BINARY we return EOF.
2500  *
2501  * PQgetline reads up to maxlen-1 characters (like fgets(3)) but strips
2502  * the terminating \n (like gets(3)).
2503  *
2504  * CAUTION: the caller is responsible for detecting the end-of-copy signal
2505  * (a line containing just "\.") when using this routine.
2506  *
2507  * RETURNS:
2508  * EOF if error (eg, invalid arguments are given)
2509  * 0 if EOL is reached (i.e., \n has been read)
2510  * (this is required for backward-compatibility -- this
2511  * routine used to always return EOF or 0, assuming that
2512  * the line ended within maxlen bytes.)
2513  * 1 in other cases (i.e., the buffer was filled before \n is reached)
2514  */
2515 int
2516 PQgetline(PGconn *conn, char *s, int maxlen)
2517 {
2518  if (!s || maxlen <= 0)
2519  return EOF;
2520  *s = '\0';
2521  /* maxlen must be at least 3 to hold the \. terminator! */
2522  if (maxlen < 3)
2523  return EOF;
2524 
2525  if (!conn)
2526  return EOF;
2527 
2528  if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
2529  return pqGetline3(conn, s, maxlen);
2530  else
2531  return pqGetline2(conn, s, maxlen);
2532 }
2533 
2534 /*
2535  * PQgetlineAsync - gets a COPY data row without blocking.
2536  *
2537  * This routine is for applications that want to do "COPY <rel> to stdout"
2538  * asynchronously, that is without blocking. Having issued the COPY command
2539  * and gotten a PGRES_COPY_OUT response, the app should call PQconsumeInput
2540  * and this routine until the end-of-data signal is detected. Unlike
2541  * PQgetline, this routine takes responsibility for detecting end-of-data.
2542  *
2543  * On each call, PQgetlineAsync will return data if a complete data row
2544  * is available in libpq's input buffer. Otherwise, no data is returned
2545  * until the rest of the row arrives.
2546  *
2547  * If -1 is returned, the end-of-data signal has been recognized (and removed
2548  * from libpq's input buffer). The caller *must* next call PQendcopy and
2549  * then return to normal processing.
2550  *
2551  * RETURNS:
2552  * -1 if the end-of-copy-data marker has been recognized
2553  * 0 if no data is available
2554  * >0 the number of bytes returned.
2555  *
2556  * The data returned will not extend beyond a data-row boundary. If possible
2557  * a whole row will be returned at one time. But if the buffer offered by
2558  * the caller is too small to hold a row sent by the backend, then a partial
2559  * data row will be returned. In text mode this can be detected by testing
2560  * whether the last returned byte is '\n' or not.
2561  *
2562  * The returned data is *not* null-terminated.
2563  */
2564 
2565 int
2566 PQgetlineAsync(PGconn *conn, char *buffer, int bufsize)
2567 {
2568  if (!conn)
2569  return -1;
2570 
2571  if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
2572  return pqGetlineAsync3(conn, buffer, bufsize);
2573  else
2574  return pqGetlineAsync2(conn, buffer, bufsize);
2575 }
2576 
2577 /*
2578  * PQputline -- sends a string to the backend during COPY IN.
2579  * Returns 0 if OK, EOF if not.
2580  *
2581  * This is deprecated primarily because the return convention doesn't allow
2582  * caller to tell the difference between a hard error and a nonblock-mode
2583  * send failure.
2584  */
2585 int
2586 PQputline(PGconn *conn, const char *s)
2587 {
2588  return PQputnbytes(conn, s, strlen(s));
2589 }
2590 
2591 /*
2592  * PQputnbytes -- like PQputline, but buffer need not be null-terminated.
2593  * Returns 0 if OK, EOF if not.
2594  */
2595 int
2596 PQputnbytes(PGconn *conn, const char *buffer, int nbytes)
2597 {
2598  if (PQputCopyData(conn, buffer, nbytes) > 0)
2599  return 0;
2600  else
2601  return EOF;
2602 }
2603 
2604 /*
2605  * PQendcopy
2606  * After completing the data transfer portion of a copy in/out,
2607  * the application must call this routine to finish the command protocol.
2608  *
2609  * When using protocol 3.0 this is deprecated; it's cleaner to use PQgetResult
2610  * to get the transfer status. Note however that when using 2.0 protocol,
2611  * recovering from a copy failure often requires a PQreset. PQendcopy will
2612  * take care of that, PQgetResult won't.
2613  *
2614  * RETURNS:
2615  * 0 on success
2616  * 1 on failure
2617  */
2618 int
2620 {
2621  if (!conn)
2622  return 0;
2623 
2624  if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
2625  return pqEndcopy3(conn);
2626  else
2627  return pqEndcopy2(conn);
2628 }
2629 
2630 
2631 /* ----------------
2632  * PQfn - Send a function call to the POSTGRES backend.
2633  *
2634  * conn : backend connection
2635  * fnid : OID of function to be called
2636  * result_buf : pointer to result buffer
2637  * result_len : actual length of result is returned here
2638  * result_is_int : If the result is an integer, this must be 1,
2639  * otherwise this should be 0
2640  * args : pointer to an array of function arguments
2641  * (each has length, if integer, and value/pointer)
2642  * nargs : # of arguments in args array.
2643  *
2644  * RETURNS
2645  * PGresult with status = PGRES_COMMAND_OK if successful.
2646  * *result_len is > 0 if there is a return value, 0 if not.
2647  * PGresult with status = PGRES_FATAL_ERROR if backend returns an error.
2648  * NULL on communications failure. conn->errorMessage will be set.
2649  * ----------------
2650  */
2651 
2652 PGresult *
2654  int fnid,
2655  int *result_buf,
2656  int *result_len,
2657  int result_is_int,
2658  const PQArgBlock *args,
2659  int nargs)
2660 {
2661  *result_len = 0;
2662 
2663  if (!conn)
2664  return NULL;
2665 
2666  /* clear the error string */
2668 
2669  if (conn->sock == PGINVALID_SOCKET || conn->asyncStatus != PGASYNC_IDLE ||
2670  conn->result != NULL)
2671  {
2673  libpq_gettext("connection in wrong state\n"));
2674  return NULL;
2675  }
2676 
2677  if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
2678  return pqFunctionCall3(conn, fnid,
2679  result_buf, result_len,
2680  result_is_int,
2681  args, nargs);
2682  else
2683  return pqFunctionCall2(conn, fnid,
2684  result_buf, result_len,
2685  result_is_int,
2686  args, nargs);
2687 }
2688 
2689 
2690 /* ====== accessor funcs for PGresult ======== */
2691 
2694 {
2695  if (!res)
2696  return PGRES_FATAL_ERROR;
2697  return res->resultStatus;
2698 }
2699 
2700 char *
2702 {
2703  if ((unsigned int) status >= sizeof pgresStatus / sizeof pgresStatus[0])
2704  return libpq_gettext("invalid ExecStatusType code");
2705  return pgresStatus[status];
2706 }
2707 
2708 char *
2710 {
2711  if (!res || !res->errMsg)
2712  return "";
2713  return res->errMsg;
2714 }
2715 
2716 char *
2718  PGVerbosity verbosity,
2719  PGContextVisibility show_context)
2720 {
2721  PQExpBufferData workBuf;
2722 
2723  /*
2724  * Because the caller is expected to free the result string, we must
2725  * strdup any constant result. We use plain strdup and document that
2726  * callers should expect NULL if out-of-memory.
2727  */
2728  if (!res ||
2729  (res->resultStatus != PGRES_FATAL_ERROR &&
2731  return strdup(libpq_gettext("PGresult is not an error result\n"));
2732 
2733  initPQExpBuffer(&workBuf);
2734 
2735  /*
2736  * Currently, we pass this off to fe-protocol3.c in all cases; it will
2737  * behave reasonably sanely with an error reported by fe-protocol2.c as
2738  * well. If necessary, we could record the protocol version in PGresults
2739  * so as to be able to invoke a version-specific message formatter, but
2740  * for now there's no need.
2741  */
2742  pqBuildErrorMessage3(&workBuf, res, verbosity, show_context);
2743 
2744  /* If insufficient memory to format the message, fail cleanly */
2745  if (PQExpBufferDataBroken(workBuf))
2746  {
2747  termPQExpBuffer(&workBuf);
2748  return strdup(libpq_gettext("out of memory\n"));
2749  }
2750 
2751  return workBuf.data;
2752 }
2753 
2754 char *
2755 PQresultErrorField(const PGresult *res, int fieldcode)
2756 {
2757  PGMessageField *pfield;
2758 
2759  if (!res)
2760  return NULL;
2761  for (pfield = res->errFields; pfield != NULL; pfield = pfield->next)
2762  {
2763  if (pfield->code == fieldcode)
2764  return pfield->contents;
2765  }
2766  return NULL;
2767 }
2768 
2769 int
2770 PQntuples(const PGresult *res)
2771 {
2772  if (!res)
2773  return 0;
2774  return res->ntups;
2775 }
2776 
2777 int
2778 PQnfields(const PGresult *res)
2779 {
2780  if (!res)
2781  return 0;
2782  return res->numAttributes;
2783 }
2784 
2785 int
2787 {
2788  if (!res)
2789  return 0;
2790  return res->binary;
2791 }
2792 
2793 /*
2794  * Helper routines to range-check field numbers and tuple numbers.
2795  * Return true if OK, false if not
2796  */
2797 
2798 static int
2799 check_field_number(const PGresult *res, int field_num)
2800 {
2801  if (!res)
2802  return false; /* no way to display error message... */
2803  if (field_num < 0 || field_num >= res->numAttributes)
2804  {
2806  "column number %d is out of range 0..%d",
2807  field_num, res->numAttributes - 1);
2808  return false;
2809  }
2810  return true;
2811 }
2812 
2813 static int
2815  int tup_num, int field_num)
2816 {
2817  if (!res)
2818  return false; /* no way to display error message... */
2819  if (tup_num < 0 || tup_num >= res->ntups)
2820  {
2822  "row number %d is out of range 0..%d",
2823  tup_num, res->ntups - 1);
2824  return false;
2825  }
2826  if (field_num < 0 || field_num >= res->numAttributes)
2827  {
2829  "column number %d is out of range 0..%d",
2830  field_num, res->numAttributes - 1);
2831  return false;
2832  }
2833  return true;
2834 }
2835 
2836 static int
2837 check_param_number(const PGresult *res, int param_num)
2838 {
2839  if (!res)
2840  return false; /* no way to display error message... */
2841  if (param_num < 0 || param_num >= res->numParameters)
2842  {
2844  "parameter number %d is out of range 0..%d",
2845  param_num, res->numParameters - 1);
2846  return false;
2847  }
2848 
2849  return true;
2850 }
2851 
2852 /*
2853  * returns NULL if the field_num is invalid
2854  */
2855 char *
2856 PQfname(const PGresult *res, int field_num)
2857 {
2858  if (!check_field_number(res, field_num))
2859  return NULL;
2860  if (res->attDescs)
2861  return res->attDescs[field_num].name;
2862  else
2863  return NULL;
2864 }
2865 
2866 /*
2867  * PQfnumber: find column number given column name
2868  *
2869  * The column name is parsed as if it were in a SQL statement, including
2870  * case-folding and double-quote processing. But note a possible gotcha:
2871  * downcasing in the frontend might follow different locale rules than
2872  * downcasing in the backend...
2873  *
2874  * Returns -1 if no match. In the present backend it is also possible
2875  * to have multiple matches, in which case the first one is found.
2876  */
2877 int
2878 PQfnumber(const PGresult *res, const char *field_name)
2879 {
2880  char *field_case;
2881  bool in_quotes;
2882  bool all_lower = true;
2883  const char *iptr;
2884  char *optr;
2885  int i;
2886 
2887  if (!res)
2888  return -1;
2889 
2890  /*
2891  * Note: it is correct to reject a zero-length input string; the proper
2892  * input to match a zero-length field name would be "".
2893  */
2894  if (field_name == NULL ||
2895  field_name[0] == '\0' ||
2896  res->attDescs == NULL)
2897  return -1;
2898 
2899  /*
2900  * Check if we can avoid the strdup() and related work because the
2901  * passed-in string wouldn't be changed before we do the check anyway.
2902  */
2903  for (iptr = field_name; *iptr; iptr++)
2904  {
2905  char c = *iptr;
2906 
2907  if (c == '"' || c != pg_tolower((unsigned char) c))
2908  {
2909  all_lower = false;
2910  break;
2911  }
2912  }
2913 
2914  if (all_lower)
2915  for (i = 0; i < res->numAttributes; i++)
2916  if (strcmp(field_name, res->attDescs[i].name) == 0)
2917  return i;
2918 
2919  /* Fall through to the normal check if that didn't work out. */
2920 
2921  /*
2922  * Note: this code will not reject partially quoted strings, eg
2923  * foo"BAR"foo will become fooBARfoo when it probably ought to be an error
2924  * condition.
2925  */
2926  field_case = strdup(field_name);
2927  if (field_case == NULL)
2928  return -1; /* grotty */
2929 
2930  in_quotes = false;
2931  optr = field_case;
2932  for (iptr = field_case; *iptr; iptr++)
2933  {
2934  char c = *iptr;
2935 
2936  if (in_quotes)
2937  {
2938  if (c == '"')
2939  {
2940  if (iptr[1] == '"')
2941  {
2942  /* doubled quotes become a single quote */
2943  *optr++ = '"';
2944  iptr++;
2945  }
2946  else
2947  in_quotes = false;
2948  }
2949  else
2950  *optr++ = c;
2951  }
2952  else if (c == '"')
2953  in_quotes = true;
2954  else
2955  {
2956  c = pg_tolower((unsigned char) c);
2957  *optr++ = c;
2958  }
2959  }
2960  *optr = '\0';
2961 
2962  for (i = 0; i < res->numAttributes; i++)
2963  {
2964  if (strcmp(field_case, res->attDescs[i].name) == 0)
2965  {
2966  free(field_case);
2967  return i;
2968  }
2969  }
2970  free(field_case);
2971  return -1;
2972 }
2973 
2974 Oid
2975 PQftable(const PGresult *res, int field_num)
2976 {
2977  if (!check_field_number(res, field_num))
2978  return InvalidOid;
2979  if (res->attDescs)
2980  return res->attDescs[field_num].tableid;
2981  else
2982  return InvalidOid;
2983 }
2984 
2985 int
2986 PQftablecol(const PGresult *res, int field_num)
2987 {
2988  if (!check_field_number(res, field_num))
2989  return 0;
2990  if (res->attDescs)
2991  return res->attDescs[field_num].columnid;
2992  else
2993  return 0;
2994 }
2995 
2996 int
2997 PQfformat(const PGresult *res, int field_num)
2998 {
2999  if (!check_field_number(res, field_num))
3000  return 0;
3001  if (res->attDescs)
3002  return res->attDescs[field_num].format;
3003  else
3004  return 0;
3005 }
3006 
3007 Oid
3008 PQftype(const PGresult *res, int field_num)
3009 {
3010  if (!check_field_number(res, field_num))
3011  return InvalidOid;
3012  if (res->attDescs)
3013  return res->attDescs[field_num].typid;
3014  else
3015  return InvalidOid;
3016 }
3017 
3018 int
3019 PQfsize(const PGresult *res, int field_num)
3020 {
3021  if (!check_field_number(res, field_num))
3022  return 0;
3023  if (res->attDescs)
3024  return res->attDescs[field_num].typlen;
3025  else
3026  return 0;
3027 }
3028 
3029 int
3030 PQfmod(const PGresult *res, int field_num)
3031 {
3032  if (!check_field_number(res, field_num))
3033  return 0;
3034  if (res->attDescs)
3035  return res->attDescs[field_num].atttypmod;
3036  else
3037  return 0;
3038 }
3039 
3040 char *
3042 {
3043  if (!res)
3044  return NULL;
3045  return res->cmdStatus;
3046 }
3047 
3048 /*
3049  * PQoidStatus -
3050  * if the last command was an INSERT, return the oid string
3051  * if not, return ""
3052  */
3053 char *
3055 {
3056  /*
3057  * This must be enough to hold the result. Don't laugh, this is better
3058  * than what this function used to do.
3059  */
3060  static char buf[24];
3061 
3062  size_t len;
3063 
3064  if (!res || strncmp(res->cmdStatus, "INSERT ", 7) != 0)
3065  return "";
3066 
3067  len = strspn(res->cmdStatus + 7, "0123456789");
3068  if (len > sizeof(buf) - 1)
3069  len = sizeof(buf) - 1;
3070  memcpy(buf, res->cmdStatus + 7, len);
3071  buf[len] = '\0';
3072 
3073  return buf;
3074 }
3075 
3076 /*
3077  * PQoidValue -
3078  * a perhaps preferable form of the above which just returns
3079  * an Oid type
3080  */
3081 Oid
3083 {
3084  char *endptr = NULL;
3085  unsigned long result;
3086 
3087  if (!res ||
3088  strncmp(res->cmdStatus, "INSERT ", 7) != 0 ||
3089  res->cmdStatus[7] < '0' ||
3090  res->cmdStatus[7] > '9')
3091  return InvalidOid;
3092 
3093  result = strtoul(res->cmdStatus + 7, &endptr, 10);
3094 
3095  if (!endptr || (*endptr != ' ' && *endptr != '\0'))
3096  return InvalidOid;
3097  else
3098  return (Oid) result;
3099 }
3100 
3101 
3102 /*
3103  * PQcmdTuples -
3104  * If the last command was INSERT/UPDATE/DELETE/MOVE/FETCH/COPY, return
3105  * a string containing the number of inserted/affected tuples. If not,
3106  * return "".
3107  *
3108  * XXX: this should probably return an int
3109  */
3110 char *
3112 {
3113  char *p,
3114  *c;
3115 
3116  if (!res)
3117  return "";
3118 
3119  if (strncmp(res->cmdStatus, "INSERT ", 7) == 0)
3120  {
3121  p = res->cmdStatus + 7;
3122  /* INSERT: skip oid and space */
3123  while (*p && *p != ' ')
3124  p++;
3125  if (*p == 0)
3126  goto interpret_error; /* no space? */
3127  p++;
3128  }
3129  else if (strncmp(res->cmdStatus, "SELECT ", 7) == 0 ||
3130  strncmp(res->cmdStatus, "DELETE ", 7) == 0 ||
3131  strncmp(res->cmdStatus, "UPDATE ", 7) == 0)
3132  p = res->cmdStatus + 7;
3133  else if (strncmp(res->cmdStatus, "FETCH ", 6) == 0)
3134  p = res->cmdStatus + 6;
3135  else if (strncmp(res->cmdStatus, "MOVE ", 5) == 0 ||
3136  strncmp(res->cmdStatus, "COPY ", 5) == 0)
3137  p = res->cmdStatus + 5;
3138  else
3139  return "";
3140 
3141  /* check that we have an integer (at least one digit, nothing else) */
3142  for (c = p; *c; c++)
3143  {
3144  if (!isdigit((unsigned char) *c))
3145  goto interpret_error;
3146  }
3147  if (c == p)
3148  goto interpret_error;
3149 
3150  return p;
3151 
3152 interpret_error:
3154  "could not interpret result from server: %s",
3155  res->cmdStatus);
3156  return "";
3157 }
3158 
3159 /*
3160  * PQgetvalue:
3161  * return the value of field 'field_num' of row 'tup_num'
3162  */
3163 char *
3164 PQgetvalue(const PGresult *res, int tup_num, int field_num)
3165 {
3166  if (!check_tuple_field_number(res, tup_num, field_num))
3167  return NULL;
3168  return res->tuples[tup_num][field_num].value;
3169 }
3170 
3171 /* PQgetlength:
3172  * returns the actual length of a field value in bytes.
3173  */
3174 int
3175 PQgetlength(const PGresult *res, int tup_num, int field_num)
3176 {
3177  if (!check_tuple_field_number(res, tup_num, field_num))
3178  return 0;
3179  if (res->tuples[tup_num][field_num].len != NULL_LEN)
3180  return res->tuples[tup_num][field_num].len;
3181  else
3182  return 0;
3183 }
3184 
3185 /* PQgetisnull:
3186  * returns the null status of a field value.
3187  */
3188 int
3189 PQgetisnull(const PGresult *res, int tup_num, int field_num)
3190 {
3191  if (!check_tuple_field_number(res, tup_num, field_num))
3192  return 1; /* pretend it is null */
3193  if (res->tuples[tup_num][field_num].len == NULL_LEN)
3194  return 1;
3195  else
3196  return 0;
3197 }
3198 
3199 /* PQnparams:
3200  * returns the number of input parameters of a prepared statement.
3201  */
3202 int
3203 PQnparams(const PGresult *res)
3204 {
3205  if (!res)
3206  return 0;
3207  return res->numParameters;
3208 }
3209 
3210 /* PQparamtype:
3211  * returns type Oid of the specified statement parameter.
3212  */
3213 Oid
3214 PQparamtype(const PGresult *res, int param_num)
3215 {
3216  if (!check_param_number(res, param_num))
3217  return InvalidOid;
3218  if (res->paramDescs)
3219  return res->paramDescs[param_num].typid;
3220  else
3221  return InvalidOid;
3222 }
3223 
3224 
3225 /* PQsetnonblocking:
3226  * sets the PGconn's database connection non-blocking if the arg is true
3227  * or makes it blocking if the arg is false, this will not protect
3228  * you from PQexec(), you'll only be safe when using the non-blocking API.
3229  * Needs to be called only on a connected database connection.
3230  */
3231 int
3233 {
3234  bool barg;
3235 
3236  if (!conn || conn->status == CONNECTION_BAD)
3237  return -1;
3238 
3239  barg = (arg ? true : false);
3240 
3241  /* early out if the socket is already in the state requested */
3242  if (barg == conn->nonblocking)
3243  return 0;
3244 
3245  /*
3246  * to guarantee constancy for flushing/query/result-polling behavior we
3247  * need to flush the send queue at this point in order to guarantee proper
3248  * behavior. this is ok because either they are making a transition _from_
3249  * or _to_ blocking mode, either way we can block them.
3250  */
3251  /* if we are going from blocking to non-blocking flush here */
3252  if (pqFlush(conn))
3253  return -1;
3254 
3255  conn->nonblocking = barg;
3256 
3257  return 0;
3258 }
3259 
3260 /*
3261  * return the blocking status of the database connection
3262  * true == nonblocking, false == blocking
3263  */
3264 int
3266 {
3267  return pqIsnonblocking(conn);
3268 }
3269 
3270 /* libpq is thread-safe? */
3271 int
3273 {
3274 #ifdef ENABLE_THREAD_SAFETY
3275  return true;
3276 #else
3277  return false;
3278 #endif
3279 }
3280 
3281 
3282 /* try to force data out, really only useful for non-blocking users */
3283 int
3285 {
3286  return pqFlush(conn);
3287 }
3288 
3289 
3290 /*
3291  * PQfreemem - safely frees memory allocated
3292  *
3293  * Needed mostly by Win32, unless multithreaded DLL (/MD in VC6)
3294  * Used for freeing memory from PQescapeBytea()/PQunescapeBytea()
3295  */
3296 void
3297 PQfreemem(void *ptr)
3298 {
3299  free(ptr);
3300 }
3301 
3302 /*
3303  * PQfreeNotify - free's the memory associated with a PGnotify
3304  *
3305  * This function is here only for binary backward compatibility.
3306  * New code should use PQfreemem(). A macro will automatically map
3307  * calls to PQfreemem. It should be removed in the future. bjm 2003-03-24
3308  */
3309 
3310 #undef PQfreeNotify
3311 void PQfreeNotify(PGnotify *notify);
3312 
3313 void
3315 {
3316  PQfreemem(notify);
3317 }
3318 
3319 
3320 /*
3321  * Escaping arbitrary strings to get valid SQL literal strings.
3322  *
3323  * Replaces "'" with "''", and if not std_strings, replaces "\" with "\\".
3324  *
3325  * length is the length of the source string. (Note: if a terminating NUL
3326  * is encountered sooner, PQescapeString stops short of "length"; the behavior
3327  * is thus rather like strncpy.)
3328  *
3329  * For safety the buffer at "to" must be at least 2*length + 1 bytes long.
3330  * A terminating NUL character is added to the output string, whether the
3331  * input is NUL-terminated or not.
3332  *
3333  * Returns the actual length of the output (not counting the terminating NUL).
3334  */
3335 static size_t
3337  char *to, const char *from, size_t length,
3338  int *error,
3339  int encoding, bool std_strings)
3340 {
3341  const char *source = from;
3342  char *target = to;
3343  size_t remaining = length;
3344 
3345  if (error)
3346  *error = 0;
3347 
3348  while (remaining > 0 && *source != '\0')
3349  {
3350  char c = *source;
3351  int len;
3352  int i;
3353 
3354  /* Fast path for plain ASCII */
3355  if (!IS_HIGHBIT_SET(c))
3356  {
3357  /* Apply quoting if needed */
3358  if (SQL_STR_DOUBLE(c, !std_strings))
3359  *target++ = c;
3360  /* Copy the character */
3361  *target++ = c;
3362  source++;
3363  remaining--;
3364  continue;
3365  }
3366 
3367  /* Slow path for possible multibyte characters */
3368  len = pg_encoding_mblen(encoding, source);
3369 
3370  /* Copy the character */
3371  for (i = 0; i < len; i++)
3372  {
3373  if (remaining == 0 || *source == '\0')
3374  break;
3375  *target++ = *source++;
3376  remaining--;
3377  }
3378 
3379  /*
3380  * If we hit premature end of string (ie, incomplete multibyte
3381  * character), try to pad out to the correct length with spaces. We
3382  * may not be able to pad completely, but we will always be able to
3383  * insert at least one pad space (since we'd not have quoted a
3384  * multibyte character). This should be enough to make a string that
3385  * the server will error out on.
3386  */
3387  if (i < len)
3388  {
3389  if (error)
3390  *error = 1;
3391  if (conn)
3393  libpq_gettext("incomplete multibyte character\n"));
3394  for (; i < len; i++)
3395  {
3396  if (((size_t) (target - to)) / 2 >= length)
3397  break;
3398  *target++ = ' ';
3399  }
3400  break;
3401  }
3402  }
3403 
3404  /* Write the terminating NUL character. */
3405  *target = '\0';
3406 
3407  return target - to;
3408 }
3409 
3410 size_t
3412  char *to, const char *from, size_t length,
3413  int *error)
3414 {
3415  if (!conn)
3416  {
3417  /* force empty-string result */
3418  *to = '\0';
3419  if (error)
3420  *error = 1;
3421  return 0;
3422  }
3423  return PQescapeStringInternal(conn, to, from, length, error,
3424  conn->client_encoding,
3425  conn->std_strings);
3426 }
3427 
3428 size_t
3429 PQescapeString(char *to, const char *from, size_t length)
3430 {
3431  return PQescapeStringInternal(NULL, to, from, length, NULL,
3434 }
3435 
3436 
3437 /*
3438  * Escape arbitrary strings. If as_ident is true, we escape the result
3439  * as an identifier; if false, as a literal. The result is returned in
3440  * a newly allocated buffer. If we fail due to an encoding violation or out
3441  * of memory condition, we return NULL, storing an error message into conn.
3442  */
3443 static char *
3444 PQescapeInternal(PGconn *conn, const char *str, size_t len, bool as_ident)
3445 {
3446  const char *s;
3447  char *result;
3448  char *rp;
3449  int num_quotes = 0; /* single or double, depending on as_ident */
3450  int num_backslashes = 0;
3451  int input_len;
3452  int result_size;
3453  char quote_char = as_ident ? '"' : '\'';
3454 
3455  /* We must have a connection, else fail immediately. */
3456  if (!conn)
3457  return NULL;
3458 
3459  /* Scan the string for characters that must be escaped. */
3460  for (s = str; (s - str) < len && *s != '\0'; ++s)
3461  {
3462  if (*s == quote_char)
3463  ++num_quotes;
3464  else if (*s == '\\')
3465  ++num_backslashes;
3466  else if (IS_HIGHBIT_SET(*s))
3467  {
3468  int charlen;
3469 
3470  /* Slow path for possible multibyte characters */
3471  charlen = pg_encoding_mblen(conn->client_encoding, s);
3472 
3473  /* Multibyte character overruns allowable length. */
3474  if ((s - str) + charlen > len || memchr(s, 0, charlen) != NULL)
3475  {
3477  libpq_gettext("incomplete multibyte character\n"));
3478  return NULL;
3479  }
3480 
3481  /* Adjust s, bearing in mind that for loop will increment it. */
3482  s += charlen - 1;
3483  }
3484  }
3485 
3486  /* Allocate output buffer. */
3487  input_len = s - str;
3488  result_size = input_len + num_quotes + 3; /* two quotes, plus a NUL */
3489  if (!as_ident && num_backslashes > 0)
3490  result_size += num_backslashes + 2;
3491  result = rp = (char *) malloc(result_size);
3492  if (rp == NULL)
3493  {
3495  libpq_gettext("out of memory\n"));
3496  return NULL;
3497  }
3498 
3499  /*
3500  * If we are escaping a literal that contains backslashes, we use the
3501  * escape string syntax so that the result is correct under either value
3502  * of standard_conforming_strings. We also emit a leading space in this
3503  * case, to guard against the possibility that the result might be
3504  * interpolated immediately following an identifier.
3505  */
3506  if (!as_ident && num_backslashes > 0)
3507  {
3508  *rp++ = ' ';
3509  *rp++ = 'E';
3510  }
3511 
3512  /* Opening quote. */
3513  *rp++ = quote_char;
3514 
3515  /*
3516  * Use fast path if possible.
3517  *
3518  * We've already verified that the input string is well-formed in the
3519  * current encoding. If it contains no quotes and, in the case of
3520  * literal-escaping, no backslashes, then we can just copy it directly to
3521  * the output buffer, adding the necessary quotes.
3522  *
3523  * If not, we must rescan the input and process each character
3524  * individually.
3525  */
3526  if (num_quotes == 0 && (num_backslashes == 0 || as_ident))
3527  {
3528  memcpy(rp, str, input_len);
3529  rp += input_len;
3530  }
3531  else
3532  {
3533  for (s = str; s - str < input_len; ++s)
3534  {
3535  if (*s == quote_char || (!as_ident && *s == '\\'))
3536  {
3537  *rp++ = *s;
3538  *rp++ = *s;
3539  }
3540  else if (!IS_HIGHBIT_SET(*s))
3541  *rp++ = *s;
3542  else
3543  {
3544  int i = pg_encoding_mblen(conn->client_encoding, s);
3545 
3546  while (1)
3547  {
3548  *rp++ = *s;
3549  if (--i == 0)
3550  break;
3551  ++s; /* for loop will provide the final increment */
3552  }
3553  }
3554  }
3555  }
3556 
3557  /* Closing quote and terminating NUL. */
3558  *rp++ = quote_char;
3559  *rp = '\0';
3560 
3561  return result;
3562 }
3563 
3564 char *
3565 PQescapeLiteral(PGconn *conn, const char *str, size_t len)
3566 {
3567  return PQescapeInternal(conn, str, len, false);
3568 }
3569 
3570 char *
3571 PQescapeIdentifier(PGconn *conn, const char *str, size_t len)
3572 {
3573  return PQescapeInternal(conn, str, len, true);
3574 }
3575 
3576 /* HEX encoding support for bytea */
3577 static const char hextbl[] = "0123456789abcdef";
3578 
3579 static const int8 hexlookup[128] = {
3580  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
3581  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
3582  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
3583  0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1,
3584  -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
3585  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
3586  -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
3587  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
3588 };
3589 
3590 static inline char
3591 get_hex(char c)
3592 {
3593  int res = -1;
3594 
3595  if (c > 0 && c < 127)
3596  res = hexlookup[(unsigned char) c];
3597 
3598  return (char) res;
3599 }
3600 
3601 
3602 /*
3603  * PQescapeBytea - converts from binary string to the
3604  * minimal encoding necessary to include the string in an SQL
3605  * INSERT statement with a bytea type column as the target.
3606  *
3607  * We can use either hex or escape (traditional) encoding.
3608  * In escape mode, the following transformations are applied:
3609  * '\0' == ASCII 0 == \000
3610  * '\'' == ASCII 39 == ''
3611  * '\\' == ASCII 92 == \\
3612  * anything < 0x20, or > 0x7e ---> \ooo
3613  * (where ooo is an octal expression)
3614  *
3615  * If not std_strings, all backslashes sent to the output are doubled.
3616  */
3617 static unsigned char *
3619  const unsigned char *from, size_t from_length,
3620  size_t *to_length, bool std_strings, bool use_hex)
3621 {
3622  const unsigned char *vp;
3623  unsigned char *rp;
3624  unsigned char *result;
3625  size_t i;
3626  size_t len;
3627  size_t bslash_len = (std_strings ? 1 : 2);
3628 
3629  /*
3630  * empty string has 1 char ('\0')
3631  */
3632  len = 1;
3633 
3634  if (use_hex)
3635  {
3636  len += bslash_len + 1 + 2 * from_length;
3637  }
3638  else
3639  {
3640  vp = from;
3641  for (i = from_length; i > 0; i--, vp++)
3642  {
3643  if (*vp < 0x20 || *vp > 0x7e)
3644  len += bslash_len + 3;
3645  else if (*vp == '\'')
3646  len += 2;
3647  else if (*vp == '\\')
3648  len += bslash_len + bslash_len;
3649  else
3650  len++;
3651  }
3652  }
3653 
3654  *to_length = len;
3655  rp = result = (unsigned char *) malloc(len);
3656  if (rp == NULL)
3657  {
3658  if (conn)
3660  libpq_gettext("out of memory\n"));
3661  return NULL;
3662  }
3663 
3664  if (use_hex)
3665  {
3666  if (!std_strings)
3667  *rp++ = '\\';
3668  *rp++ = '\\';
3669  *rp++ = 'x';
3670  }
3671 
3672  vp = from;
3673  for (i = from_length; i > 0; i--, vp++)
3674  {
3675  unsigned char c = *vp;
3676 
3677  if (use_hex)
3678  {
3679  *rp++ = hextbl[(c >> 4) & 0xF];
3680  *rp++ = hextbl[c & 0xF];
3681  }
3682  else if (c < 0x20 || c > 0x7e)
3683  {
3684  if (!std_strings)
3685  *rp++ = '\\';
3686  *rp++ = '\\';
3687  *rp++ = (c >> 6) + '0';
3688  *rp++ = ((c >> 3) & 07) + '0';
3689  *rp++ = (c & 07) + '0';
3690  }
3691  else if (c == '\'')
3692  {
3693  *rp++ = '\'';
3694  *rp++ = '\'';
3695  }
3696  else if (c == '\\')
3697  {
3698  if (!std_strings)
3699  {
3700  *rp++ = '\\';
3701  *rp++ = '\\';
3702  }
3703  *rp++ = '\\';
3704  *rp++ = '\\';
3705  }
3706  else
3707  *rp++ = c;
3708  }
3709  *rp = '\0';
3710 
3711  return result;
3712 }
3713 
3714 unsigned char *
3716  const unsigned char *from, size_t from_length,
3717  size_t *to_length)
3718 {
3719  if (!conn)
3720  return NULL;
3721  return PQescapeByteaInternal(conn, from, from_length, to_length,
3722  conn->std_strings,
3723  (conn->sversion >= 90000));
3724 }
3725 
3726 unsigned char *
3727 PQescapeBytea(const unsigned char *from, size_t from_length, size_t *to_length)
3728 {
3729  return PQescapeByteaInternal(NULL, from, from_length, to_length,
3731  false /* can't use hex */ );
3732 }
3733 
3734 
3735 #define ISFIRSTOCTDIGIT(CH) ((CH) >= '0' && (CH) <= '3')
3736 #define ISOCTDIGIT(CH) ((CH) >= '0' && (CH) <= '7')
3737 #define OCTVAL(CH) ((CH) - '0')
3738 
3739 /*
3740  * PQunescapeBytea - converts the null terminated string representation
3741  * of a bytea, strtext, into binary, filling a buffer. It returns a
3742  * pointer to the buffer (or NULL on error), and the size of the
3743  * buffer in retbuflen. The pointer may subsequently be used as an
3744  * argument to the function PQfreemem.
3745  *
3746  * The following transformations are made:
3747  * \\ == ASCII 92 == \
3748  * \ooo == a byte whose value = ooo (ooo is an octal number)
3749  * \x == x (x is any character not matched by the above transformations)
3750  */
3751 unsigned char *
3752 PQunescapeBytea(const unsigned char *strtext, size_t *retbuflen)
3753 {
3754  size_t strtextlen,
3755  buflen;
3756  unsigned char *buffer,
3757  *tmpbuf;
3758  size_t i,
3759  j;
3760 
3761  if (strtext == NULL)
3762  return NULL;
3763 
3764  strtextlen = strlen((const char *) strtext);
3765 
3766  if (strtext[0] == '\\' && strtext[1] == 'x')
3767  {
3768  const unsigned char *s;
3769  unsigned char *p;
3770 
3771  buflen = (strtextlen - 2) / 2;
3772  /* Avoid unportable malloc(0) */
3773  buffer = (unsigned char *) malloc(buflen > 0 ? buflen : 1);
3774  if (buffer == NULL)
3775  return NULL;
3776 
3777  s = strtext + 2;
3778  p = buffer;
3779  while (*s)
3780  {
3781  char v1,
3782  v2;
3783 
3784  /*
3785  * Bad input is silently ignored. Note that this includes
3786  * whitespace between hex pairs, which is allowed by byteain.
3787  */
3788  v1 = get_hex(*s++);
3789  if (!*s || v1 == (char) -1)
3790  continue;
3791  v2 = get_hex(*s++);
3792  if (v2 != (char) -1)
3793  *p++ = (v1 << 4) | v2;
3794  }
3795 
3796  buflen = p - buffer;
3797  }
3798  else
3799  {
3800  /*
3801  * Length of input is max length of output, but add one to avoid
3802  * unportable malloc(0) if input is zero-length.
3803  */
3804  buffer = (unsigned char *) malloc(strtextlen + 1);
3805  if (buffer == NULL)
3806  return NULL;
3807 
3808  for (i = j = 0; i < strtextlen;)
3809  {
3810  switch (strtext[i])
3811  {
3812  case '\\':
3813  i++;
3814  if (strtext[i] == '\\')
3815  buffer[j++] = strtext[i++];
3816  else
3817  {
3818  if ((ISFIRSTOCTDIGIT(strtext[i])) &&
3819  (ISOCTDIGIT(strtext[i + 1])) &&
3820  (ISOCTDIGIT(strtext[i + 2])))
3821  {
3822  int byte;
3823 
3824  byte = OCTVAL(strtext[i++]);
3825  byte = (byte << 3) + OCTVAL(strtext[i++]);
3826  byte = (byte << 3) + OCTVAL(strtext[i++]);
3827  buffer[j++] = byte;
3828  }
3829  }
3830 
3831  /*
3832  * Note: if we see '\' followed by something that isn't a
3833  * recognized escape sequence, we loop around having done
3834  * nothing except advance i. Therefore the something will
3835  * be emitted as ordinary data on the next cycle. Corner
3836  * case: '\' at end of string will just be discarded.
3837  */
3838  break;
3839 
3840  default:
3841  buffer[j++] = strtext[i++];
3842  break;
3843  }
3844  }
3845  buflen = j; /* buflen is the length of the dequoted data */
3846  }
3847 
3848  /* Shrink the buffer to be no larger than necessary */
3849  /* +1 avoids unportable behavior when buflen==0 */
3850  tmpbuf = realloc(buffer, buflen + 1);
3851 
3852  /* It would only be a very brain-dead realloc that could fail, but... */
3853  if (!tmpbuf)
3854  {
3855  free(buffer);
3856  return NULL;
3857  }
3858 
3859  *retbuflen = buflen;
3860  return tmpbuf;
3861 }
int remaining
Definition: informix.c:687
int PQputCopyData(PGconn *conn, const char *buffer, int nbytes)
Definition: fe-exec.c:2318
struct PGEvent PGEvent
int pqFlush(PGconn *conn)
Definition: fe-misc.c:998
int pqRowProcessor(PGconn *conn, const char **errmsgp)
Definition: fe-exec.c:1133
static bool static_std_strings
Definition: fe-exec.c:51
int PQgetlength(const PGresult *res, int tup_num, int field_num)
Definition: fe-exec.c:3175
size_t memorySize
Definition: libpq-int.h:212
PGresult * PQexecPrepared(PGconn *conn, const char *stmtName, int nParams, const char *const *paramValues, const int *paramLengths, const int *paramFormats, int resultFormat)
Definition: fe-exec.c:2001
int PQnfields(const PGresult *res)
Definition: fe-exec.c:2778
PGresult * PQprepare(PGconn *conn, const char *stmtName, const char *query, int nParams, const Oid *paramTypes)
Definition: fe-exec.c:1984
PGresult * PQdescribePrepared(PGconn *conn, const char *stmt)
Definition: fe-exec.c:2157
void printfPQExpBuffer(PQExpBuffer str, const char *fmt,...)
Definition: pqexpbuffer.c:237
PGMessageField * errFields
Definition: libpq-int.h:197
int PQftablecol(const PGresult *res, int field_num)
Definition: fe-exec.c:2986
size_t PQresultMemorySize(const PGresult *res)
Definition: fe-exec.c:635
int pg_char_to_encoding(const char *name)
Definition: encnames.c:551
char space[1]
Definition: libpq-int.h:106
int PQisnonblocking(const PGconn *conn)
Definition: fe-exec.c:3265
void pqParseInput2(PGconn *conn)
Definition: fe-protocol2.c:410
#define PG_DIAG_MESSAGE_PRIMARY
Definition: postgres_ext.h:58
#define ISFIRSTOCTDIGIT(CH)
Definition: fe-exec.c:3735
size_t PQescapeString(char *to, const char *from, size_t length)
Definition: fe-exec.c:3429
const PGresult * src
Definition: libpq-events.h:60
PGEvent * events
Definition: libpq-int.h:378
int PQsendQueryParams(PGconn *conn, const char *command, int nParams, const Oid *paramTypes, const char *const *paramValues, const int *paramLengths, const int *paramFormats, int resultFormat)
Definition: fe-exec.c:1286
int pqGetline3(PGconn *conn, char *s, int maxlen)
PGresult * pqFunctionCall2(PGconn *conn, Oid fnid, int *result_buf, int *actual_result_len, int result_is_int, const PQArgBlock *args, int nargs)
char * PQgetvalue(const PGresult *res, int tup_num, int field_num)
Definition: fe-exec.c:3164
int pqCheckOutBufferSpace(size_t bytes_needed, PGconn *conn)
Definition: fe-misc.c:344
static void error(void)
Definition: sql-dyntest.c:147
static int check_tuple_field_number(const PGresult *res, int tup_num, int field_num)
Definition: fe-exec.c:2814
int PQfsize(const PGresult *res, int field_num)
Definition: fe-exec.c:3019
bool singleRowMode
Definition: libpq-int.h:392
PGnotify * PQnotifies(PGconn *conn)
Definition: fe-exec.c:2290
char * PQfname(const PGresult *res, int field_num)
Definition: fe-exec.c:2856
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Definition: fe-exec.c:1015
static int check_param_number(const PGresult *res, int param_num)
Definition: fe-exec.c:2837
bool resultInitialized
Definition: libpq-int.h:164
void termPQExpBuffer(PQExpBuffer str)
Definition: pqexpbuffer.c:131
#define OCTVAL(CH)
Definition: fe-exec.c:3737
#define pqIsnonblocking(conn)
Definition: libpq-int.h:782
char * PQcmdTuples(PGresult *res)
Definition: fe-exec.c:3111
PGresult * pqFunctionCall3(PGconn *conn, Oid fnid, int *result_buf, int *actual_result_len, int result_is_int, const PQArgBlock *args, int nargs)
void appendPQExpBufferStr(PQExpBuffer str, const char *data)
Definition: pqexpbuffer.c:369
int PQputnbytes(PGconn *conn, const char *buffer, int nbytes)
Definition: fe-exec.c:2596
int outCount
Definition: libpq-int.h:448
int PQsetvalue(PGresult *res, int tup_num, int field_num, char *value, int len)
Definition: fe-exec.c:432
Oid PQoidValue(const PGresult *res)
Definition: fe-exec.c:3082
Oid PQftable(const PGresult *res, int field_num)
Definition: fe-exec.c:2975
static struct @144 value
int PQsendDescribePortal(PGconn *conn, const char *portal)
Definition: fe-exec.c:2206
int tupArrSize
Definition: libpq-int.h:174
static int PQsendQueryGuts(PGconn *conn, const char *command, const char *stmtName, int nParams, const Oid *paramTypes, const char *const *paramValues, const int *paramLengths, const int *paramFormats, int resultFormat)
Definition: fe-exec.c:1509
PGresult_data * next
Definition: libpq-int.h:105
PGresult * PQcopyResult(const PGresult *src, int flags)
Definition: fe-exec.c:295
union pgresult_data PGresult_data
Definition: libpq-int.h:101
PGQueryClass queryclass
Definition: libpq-int.h:386
char * PQresStatus(ExecStatusType status)
Definition: fe-exec.c:2701
Oid PQparamtype(const PGresult *res, int param_num)
Definition: fe-exec.c:3214
int PQgetlineAsync(PGconn *conn, char *buffer, int bufsize)
Definition: fe-exec.c:2566
int pqPutMsgStart(char msg_type, bool force_len, PGconn *conn)
Definition: fe-misc.c:519
PGnotify * notifyHead
Definition: libpq-int.h:395
unsigned char pg_tolower(unsigned char ch)
Definition: pgstrcasecmp.c:122
int pqGetlineAsync2(PGconn *conn, char *buffer, int bufsize)
int PQputCopyEnd(PGconn *conn, const char *errormsg)
Definition: fe-exec.c:2385
struct pgMessageField * next
Definition: libpq-int.h:144
ExecStatusType
Definition: libpq-fe.h:84
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Definition: libpq-int.h:210
PGresult * PQdescribePortal(PGconn *conn, const char *portal)
Definition: fe-exec.c:2176
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Definition: fe-exec.c:2786
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Definition: libpq-int.h:188
unsigned int Oid
Definition: postgres_ext.h:31
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Definition: libpq-int.h:133
#define PG_PROTOCOL_MAJOR(v)
Definition: pqcomm.h:104
char * PQoidStatus(const PGresult *res)
Definition: fe-exec.c:3054
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Definition: fe-exec.c:2770
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Definition: port.h:196
char * errMsg
Definition: libpq-int.h:196
char * write_err_msg
Definition: libpq-int.h:416
PGresult * PQfn(PGconn *conn, int fnid, int *result_buf, int *result_len, int result_is_int, const PQArgBlock *args, int nargs)
Definition: fe-exec.c:2653
PGresult * pqPrepareAsyncResult(PGconn *conn)
Definition: fe-exec.c:827
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Definition: libpq-fe.h:242
ExecStatusType PQresultStatus(const PGresult *res)
Definition: fe-exec.c:2693
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Definition: libpq-int.h:201
PGresAttDesc * attDescs
Definition: libpq-int.h:171
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Definition: libpq-fe.h:35
FILE * Pfdebug
Definition: libpq-int.h:372
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Definition: fe-exec.c:2474
PGresult * result
Definition: libpq-int.h:460
PGresAttValue ** tuples
Definition: libpq-int.h:172
static int PQsendDescribe(PGconn *conn, char desc_type, const char *desc_target)
Definition: fe-exec.c:2221
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Definition: header.h:50
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Definition: fe-misc.c:307
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Definition: libpq-int.h:410
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Definition: fe-exec.c:2586
int pqGetlineAsync3(PGconn *conn, char *buffer, int bufsize)
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Definition: fe-exec.c:3591
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Definition: port.h:194
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Definition: fe-exec.c:130
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Definition: c.h:312
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Definition: fe-exec.c:1235
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Definition: fe-exec.c:3571
PGresult * next_result
Definition: libpq-int.h:461
PGAsyncStatusType asyncStatus
Definition: libpq-int.h:384
struct pg_result PGresult
Definition: libpq-fe.h:150
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Definition: c.h:1075
#define PG_COPYRES_EVENTS
Definition: libpq-fe.h:36
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static bool pqAddTuple(PGresult *res, PGresAttValue *tup, const char **errmsgp)
Definition: fe-exec.c:927
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Definition: libpq-int.h:415
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Definition: fe-exec.c:3314
PGNoticeHooks noticeHooks
Definition: libpq-int.h:186
PGconn * conn
Definition: streamutil.c:56
#define vsnprintf
Definition: port.h:191
#define PG_COPYRES_NOTICEHOOKS
Definition: libpq-fe.h:37
struct pgParameterStatus pgParameterStatus
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Definition: libpq-int.h:375
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Definition: libpq-int.h:209
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Definition: fe-exec.c:3284
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Definition: fe-exec.c:3008
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Definition: fe-misc.c:629
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Definition: libpq-int.h:155
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Definition: fe-exec.c:230
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Definition: fe-exec.c:2717
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Definition: fe-exec.c:3579
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Definition: fe-exec.c:50
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Definition: fe-misc.c:1021
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Definition: pg_test_fsync.c:68
#define PGRESULT_BLOCK_OVERHEAD
Definition: fe-exec.c:131
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Definition: fe-exec.c:1678
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Definition: fe-exec.c:1902
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Definition: libpq-int.h:152
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Definition: wchar.c:1833
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Definition: fe-exec.c:872
#define PG_DIAG_SEVERITY
Definition: postgres_ext.h:55
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Definition: fe-exec.c:2193
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Definition: libpq-int.h:208
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Definition: fe-exec.c:3411
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Definition: libpq-int.h:175
PGresult * PQmakeEmptyPGresult(PGconn *conn, ExecStatusType status)
Definition: fe-exec.c:142
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Definition: fe-misc.c:112
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Definition: fe-misc.c:179
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Definition: libpq-int.h:387
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Definition: fe-exec.c:1741
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Definition: libpq-int.h:456
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Definition: libpq-int.h:179
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Definition: fe-exec.c:1468
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Definition: rijndael.c:68
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Definition: libpq-int.h:405
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Definition: libpq-int.h:198
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Definition: libpq-int.h:170
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Definition: c.h:344
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Definition: fe-exec.c:3752
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Definition: fe-exec.c:3041
void pqSaveMessageField(PGresult *res, char code, const char *value)
Definition: fe-exec.c:994
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Definition: libpq-int.h:431
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Definition: libpq-fe.h:120
#define PGRESULT_SEP_ALLOC_THRESHOLD
Definition: fe-exec.c:132
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Definition: port.h:33
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Definition: fe-exec.c:2878
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Definition: fe-exec.c:1705
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Definition: fe-exec.c:3232
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Definition: libpq-fe.h:170
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Definition: libpq-fe.h:112
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Definition: libpq-fe.h:246
PQnoticeProcessor noticeProc
Definition: libpq-int.h:154
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Definition: fe-exec.c:2516
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Definition: fe-exec.c:3565
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Definition: libpq-int.h:509
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Definition: postgres_ext.h:56
#define PG_COPYRES_ATTRS
Definition: libpq-fe.h:34
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Definition: libpq-int.h:433
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Definition: postgres_ext.h:36
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Definition: fe-exec.c:661
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Definition: fe-exec.c:695
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Definition: fe-exec.c:2799
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Definition: c.h:452
#define free(a)
Definition: header.h:65
#define PQExpBufferDataBroken(buf)
Definition: pqexpbuffer.h:67
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Definition: fe-exec.c:2619
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Definition: libpq-int.h:447
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Definition: fe-exec.c:535
PGresParamDesc * paramDescs
Definition: libpq-int.h:176
char * PQresultErrorField(const PGresult *res, int fieldcode)
Definition: fe-exec.c:2755
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Definition: libpq-int.h:169
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Definition: fe-misc.c:246
static size_t PQescapeStringInternal(PGconn *conn, char *to, const char *from, size_t length, int *error, int encoding, bool std_strings)
Definition: fe-exec.c:3336
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Definition: fe-exec.c:1755
int pqGetline2(PGconn *conn, char *s, int maxlen)
struct pgParameterStatus * next
Definition: libpq-int.h:261
char contents[FLEXIBLE_ARRAY_MEMBER]
Definition: libpq-int.h:146
ProtocolVersion pversion
Definition: libpq-int.h:409
PGEventProc proc
Definition: libpq-int.h:160
char cmdStatus[CMDSTATUS_LEN]
Definition: libpq-int.h:178
ConnStatusType status
Definition: libpq-int.h:383
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Definition: fe-exec.c:3030
static char * PQescapeInternal(PGconn *conn, const char *str, size_t len, bool as_ident)
Definition: fe-exec.c:3444
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Definition: fe-misc.c:587
int32 encoding
Definition: pg_database.h:41
void pqCatenateResultError(PGresult *res, const char *msg)
Definition: fe-exec.c:676
PGnotify * notifyTail
Definition: libpq-int.h:396
#define realloc(a, b)
Definition: header.h:60
const char * name
Definition: encode.c:521
static PGresult * PQexecFinish(PGconn *conn)
Definition: fe-exec.c:2096
int PQsendQueryPrepared(PGconn *conn, const char *stmtName, int nParams, const char *const *paramValues, const int *paramLengths, const int *paramFormats, int resultFormat)
Definition: fe-exec.c:1428
static StringInfoData tmpbuf
Definition: walsender.c:162
static void pqSaveWriteError(PGconn *conn)
Definition: fe-exec.c:799
bool nonblocking
Definition: libpq-int.h:390
int PQisthreadsafe(void)
Definition: fe-exec.c:3272
char * PQresultErrorMessage(const PGresult *res)
Definition: fe-exec.c:2709
#define PGRESULT_DATA_BLOCKSIZE
Definition: fe-exec.c:129
static bool PQexecStart(PGconn *conn)
Definition: fe-exec.c:2022
PGresult * PQexecParams(PGconn *conn, const char *command, int nParams, const Oid *paramTypes, const char *const *paramValues, const int *paramLengths, const int *paramFormats, int resultFormat)
Definition: fe-exec.c:1954
int errmsg(const char *fmt,...)
Definition: elog.c:784
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Definition: libpq-int.h:379
static const char hextbl[]
Definition: fe-exec.c:3577
int i
void * passThrough
Definition: libpq-int.h:162
char * name
Definition: libpq-fe.h:240
PGresult * PQexec(PGconn *conn, const char *query)
Definition: fe-exec.c:1940
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Definition: libpq-int.h:432
void * arg
#define SQL_STR_DOUBLE(ch, escape_backslash)
Definition: c.h:1083
char * value
Definition: libpq-int.h:138
void pqBuildErrorMessage3(PQExpBuffer msg, const PGresult *res, PGVerbosity verbosity, PGContextVisibility show_context)
Definition: fe-protocol3.c:989
char *const pgresStatus[]
Definition: fe-exec.c:33
unsigned char * PQescapeBytea(const unsigned char *from, size_t from_length, size_t *to_length)
Definition: fe-exec.c:3727
void pqClearAsyncResult(PGconn *conn)
Definition: fe-exec.c:750
void pqSaveErrorResult(PGconn *conn)
Definition: fe-exec.c:773
static PGEvent * dupEvents(PGEvent *events, int count, size_t *memSize)
Definition: fe-exec.c:388
PGEvent * events
Definition: libpq-int.h:187
void pqParseInput3(PGconn *conn)
Definition: fe-protocol3.c:65
int pqGetCopyData2(PGconn *conn, char **buffer, int async)
void resetPQExpBuffer(PQExpBuffer str)
Definition: pqexpbuffer.c:148
static void static void status(const char *fmt,...) pg_attribute_printf(1
Definition: pg_regress.c:227
int PQgetisnull(const PGresult *res, int tup_num, int field_num)
Definition: fe-exec.c:3189
unsigned char * PQescapeByteaConn(PGconn *conn, const unsigned char *from, size_t from_length, size_t *to_length)
Definition: fe-exec.c:3715
static unsigned char * PQescapeByteaInternal(PGconn *conn, const unsigned char *from, size_t from_length, size_t *to_length, bool std_strings, bool use_hex)
Definition: fe-exec.c:3618
int PQfformat(const PGresult *res, int field_num)
Definition: fe-exec.c:2997
PGresult * dest
Definition: libpq-events.h:61
char * name
Definition: libpq-int.h:161
ExecStatusType resultStatus
Definition: libpq-int.h:177
void PQfreemem(void *ptr)
Definition: fe-exec.c:3297
long val
Definition: informix.c:684
PGresult * PQgetResult(PGconn *conn)
Definition: fe-exec.c:1779
int pqEndcopy2(PGconn *conn)
int PQnparams(const PGresult *res)
Definition: fe-exec.c:3203
#define ISOCTDIGIT(CH)
Definition: fe-exec.c:3736
void initPQExpBuffer(PQExpBuffer str)
Definition: pqexpbuffer.c:92
#define offsetof(type, field)
Definition: c.h:655
int PQsendPrepare(PGconn *conn, const char *stmtName, const char *query, int nParams, const Oid *paramTypes)
Definition: fe-exec.c:1331
#define libpq_gettext(x)
Definition: libpq-int.h:788
char * pqResultStrdup(PGresult *res, const char *str)
Definition: fe-exec.c:647
void * PQresultAlloc(PGresult *res, size_t nBytes)
Definition: fe-exec.c:519
void * noticeRecArg
Definition: libpq-int.h:153
int client_encoding
Definition: libpq-int.h:189