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dblink.c
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1 /*
2  * dblink.c
3  *
4  * Functions returning results from a remote database
5  *
6  * Joe Conway <mail@joeconway.com>
7  * And contributors:
8  * Darko Prenosil <Darko.Prenosil@finteh.hr>
9  * Shridhar Daithankar <shridhar_daithankar@persistent.co.in>
10  *
11  * contrib/dblink/dblink.c
12  * Copyright (c) 2001-2024, PostgreSQL Global Development Group
13  * ALL RIGHTS RESERVED;
14  *
15  * Permission to use, copy, modify, and distribute this software and its
16  * documentation for any purpose, without fee, and without a written agreement
17  * is hereby granted, provided that the above copyright notice and this
18  * paragraph and the following two paragraphs appear in all copies.
19  *
20  * IN NO EVENT SHALL THE AUTHOR OR DISTRIBUTORS BE LIABLE TO ANY PARTY FOR
21  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING
22  * LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS
23  * DOCUMENTATION, EVEN IF THE AUTHOR OR DISTRIBUTORS HAVE BEEN ADVISED OF THE
24  * POSSIBILITY OF SUCH DAMAGE.
25  *
26  * THE AUTHOR AND DISTRIBUTORS SPECIFICALLY DISCLAIMS ANY WARRANTIES,
27  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
28  * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
29  * ON AN "AS IS" BASIS, AND THE AUTHOR AND DISTRIBUTORS HAS NO OBLIGATIONS TO
30  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
31  *
32  */
33 #include "postgres.h"
34 
35 #include <limits.h>
36 
37 #include "access/htup_details.h"
38 #include "access/relation.h"
39 #include "access/reloptions.h"
40 #include "access/table.h"
41 #include "catalog/namespace.h"
42 #include "catalog/pg_foreign_data_wrapper.h"
43 #include "catalog/pg_foreign_server.h"
44 #include "catalog/pg_type.h"
45 #include "catalog/pg_user_mapping.h"
46 #include "executor/spi.h"
47 #include "foreign/foreign.h"
48 #include "funcapi.h"
49 #include "lib/stringinfo.h"
50 #include "libpq-fe.h"
51 #include "libpq/libpq-be.h"
52 #include "libpq/libpq-be-fe-helpers.h"
53 #include "mb/pg_wchar.h"
54 #include "miscadmin.h"
55 #include "parser/scansup.h"
56 #include "utils/acl.h"
57 #include "utils/builtins.h"
58 #include "utils/fmgroids.h"
59 #include "utils/guc.h"
60 #include "utils/lsyscache.h"
61 #include "utils/memutils.h"
62 #include "utils/rel.h"
63 #include "utils/varlena.h"
64 #include "utils/wait_event.h"
65 
66 PG_MODULE_MAGIC;
67 
68 typedef struct remoteConn
69 {
70  PGconn *conn; /* Hold the remote connection */
71  int openCursorCount; /* The number of open cursors */
72  bool newXactForCursor; /* Opened a transaction for a cursor */
73 } remoteConn;
74 
75 typedef struct storeInfo
76 {
77  FunctionCallInfo fcinfo;
78  Tuplestorestate *tuplestore;
79  AttInMetadata *attinmeta;
80  MemoryContext tmpcontext;
81  char **cstrs;
82  /* temp storage for results to avoid leaks on exception */
83  PGresult *last_res;
84  PGresult *cur_res;
85 } storeInfo;
86 
87 /*
88  * Internal declarations
89  */
90 static Datum dblink_record_internal(FunctionCallInfo fcinfo, bool is_async);
91 static void prepTuplestoreResult(FunctionCallInfo fcinfo);
92 static void materializeResult(FunctionCallInfo fcinfo, PGconn *conn,
93  PGresult *res);
94 static void materializeQueryResult(FunctionCallInfo fcinfo,
95  PGconn *conn,
96  const char *conname,
97  const char *sql,
98  bool fail);
99 static PGresult *storeQueryResult(volatile storeInfo *sinfo, PGconn *conn, const char *sql);
100 static void storeRow(volatile storeInfo *sinfo, PGresult *res, bool first);
101 static remoteConn *getConnectionByName(const char *name);
102 static HTAB *createConnHash(void);
103 static void createNewConnection(const char *name, remoteConn *rconn);
104 static void deleteConnection(const char *name);
105 static char **get_pkey_attnames(Relation rel, int16 *indnkeyatts);
106 static char **get_text_array_contents(ArrayType *array, int *numitems);
107 static char *get_sql_insert(Relation rel, int *pkattnums, int pknumatts, char **src_pkattvals, char **tgt_pkattvals);
108 static char *get_sql_delete(Relation rel, int *pkattnums, int pknumatts, char **tgt_pkattvals);
109 static char *get_sql_update(Relation rel, int *pkattnums, int pknumatts, char **src_pkattvals, char **tgt_pkattvals);
110 static char *quote_ident_cstr(char *rawstr);
111 static int get_attnum_pk_pos(int *pkattnums, int pknumatts, int key);
112 static HeapTuple get_tuple_of_interest(Relation rel, int *pkattnums, int pknumatts, char **src_pkattvals);
113 static Relation get_rel_from_relname(text *relname_text, LOCKMODE lockmode, AclMode aclmode);
114 static char *generate_relation_name(Relation rel);
115 static void dblink_connstr_check(const char *connstr);
116 static bool dblink_connstr_has_pw(const char *connstr);
117 static void dblink_security_check(PGconn *conn, remoteConn *rconn, const char *connstr);
118 static void dblink_res_error(PGconn *conn, const char *conname, PGresult *res,
119  bool fail, const char *fmt,...) pg_attribute_printf(5, 6);
120 static char *get_connect_string(const char *servername);
121 static char *escape_param_str(const char *str);
122 static void validate_pkattnums(Relation rel,
123  int2vector *pkattnums_arg, int32 pknumatts_arg,
124  int **pkattnums, int *pknumatts);
125 static bool is_valid_dblink_option(const PQconninfoOption *options,
126  const char *option, Oid context);
127 static int applyRemoteGucs(PGconn *conn);
128 static void restoreLocalGucs(int nestlevel);
129 
130 /* Global */
131 static remoteConn *pconn = NULL;
132 static HTAB *remoteConnHash = NULL;
133 
134 /* custom wait event values, retrieved from shared memory */
135 static uint32 dblink_we_connect = 0;
136 static uint32 dblink_we_get_conn = 0;
137 static uint32 dblink_we_get_result = 0;
138 
139 /*
140  * Following is list that holds multiple remote connections.
141  * Calling convention of each dblink function changes to accept
142  * connection name as the first parameter. The connection list is
143  * much like ecpg e.g. a mapping between a name and a PGconn object.
144  */
145 
146 typedef struct remoteConnHashEnt
147 {
148  char name[NAMEDATALEN];
149  remoteConn *rconn;
150 } remoteConnHashEnt;
151 
152 /* initial number of connection hashes */
153 #define NUMCONN 16
154 
155 static char *
156 xpstrdup(const char *in)
157 {
158  if (in == NULL)
159  return NULL;
160  return pstrdup(in);
161 }
162 
163 static void
164 pg_attribute_noreturn()
165 dblink_res_internalerror(PGconn *conn, PGresult *res, const char *p2)
166 {
167  char *msg = pchomp(PQerrorMessage(conn));
168 
169  PQclear(res);
170  elog(ERROR, "%s: %s", p2, msg);
171 }
172 
173 static void
174 pg_attribute_noreturn()
175 dblink_conn_not_avail(const char *conname)
176 {
177  if (conname)
178  ereport(ERROR,
179  (errcode(ERRCODE_CONNECTION_DOES_NOT_EXIST),
180  errmsg("connection \"%s\" not available", conname)));
181  else
182  ereport(ERROR,
183  (errcode(ERRCODE_CONNECTION_DOES_NOT_EXIST),
184  errmsg("connection not available")));
185 }
186 
187 static void
188 dblink_get_conn(char *conname_or_str,
189  PGconn *volatile *conn_p, char **conname_p, volatile bool *freeconn_p)
190 {
191  remoteConn *rconn = getConnectionByName(conname_or_str);
192  PGconn *conn;
193  char *conname;
194  bool freeconn;
195 
196  if (rconn)
197  {
198  conn = rconn->conn;
199  conname = conname_or_str;
200  freeconn = false;
201  }
202  else
203  {
204  const char *connstr;
205 
206  connstr = get_connect_string(conname_or_str);
207  if (connstr == NULL)
208  connstr = conname_or_str;
209  dblink_connstr_check(connstr);
210 
211  /* first time, allocate or get the custom wait event */
212  if (dblink_we_get_conn == 0)
213  dblink_we_get_conn = WaitEventExtensionNew("DblinkGetConnect");
214 
215  /* OK to make connection */
216  conn = libpqsrv_connect(connstr, dblink_we_get_conn);
217 
218  if (PQstatus(conn) == CONNECTION_BAD)
219  {
220  char *msg = pchomp(PQerrorMessage(conn));
221 
222  libpqsrv_disconnect(conn);
223  ereport(ERROR,
224  (errcode(ERRCODE_SQLCLIENT_UNABLE_TO_ESTABLISH_SQLCONNECTION),
225  errmsg("could not establish connection"),
226  errdetail_internal("%s", msg)));
227  }
228  dblink_security_check(conn, rconn, connstr);
229  if (PQclientEncoding(conn) != GetDatabaseEncoding())
230  PQsetClientEncoding(conn, GetDatabaseEncodingName());
231  freeconn = true;
232  conname = NULL;
233  }
234 
235  *conn_p = conn;
236  *conname_p = conname;
237  *freeconn_p = freeconn;
238 }
239 
240 static PGconn *
241 dblink_get_named_conn(const char *conname)
242 {
243  remoteConn *rconn = getConnectionByName(conname);
244 
245  if (rconn)
246  return rconn->conn;
247 
248  dblink_conn_not_avail(conname);
249  return NULL; /* keep compiler quiet */
250 }
251 
252 static void
253 dblink_init(void)
254 {
255  if (!pconn)
256  {
257  if (dblink_we_get_result == 0)
258  dblink_we_get_result = WaitEventExtensionNew("DblinkGetResult");
259 
260  pconn = (remoteConn *) MemoryContextAlloc(TopMemoryContext, sizeof(remoteConn));
261  pconn->conn = NULL;
262  pconn->openCursorCount = 0;
263  pconn->newXactForCursor = false;
264  }
265 }
266 
267 /*
268  * Create a persistent connection to another database
269  */
270 PG_FUNCTION_INFO_V1(dblink_connect);
271 Datum
272 dblink_connect(PG_FUNCTION_ARGS)
273 {
274  char *conname_or_str = NULL;
275  char *connstr = NULL;
276  char *connname = NULL;
277  char *msg;
278  PGconn *conn = NULL;
279  remoteConn *rconn = NULL;
280 
281  dblink_init();
282 
283  if (PG_NARGS() == 2)
284  {
285  conname_or_str = text_to_cstring(PG_GETARG_TEXT_PP(1));
286  connname = text_to_cstring(PG_GETARG_TEXT_PP(0));
287  }
288  else if (PG_NARGS() == 1)
289  conname_or_str = text_to_cstring(PG_GETARG_TEXT_PP(0));
290 
291  if (connname)
292  {
293  rconn = (remoteConn *) MemoryContextAlloc(TopMemoryContext,
294  sizeof(remoteConn));
295  rconn->conn = NULL;
296  rconn->openCursorCount = 0;
297  rconn->newXactForCursor = false;
298  }
299 
300  /* first check for valid foreign data server */
301  connstr = get_connect_string(conname_or_str);
302  if (connstr == NULL)
303  connstr = conname_or_str;
304 
305  /* check password in connection string if not superuser */
306  dblink_connstr_check(connstr);
307 
308  /* first time, allocate or get the custom wait event */
309  if (dblink_we_connect == 0)
310  dblink_we_connect = WaitEventExtensionNew("DblinkConnect");
311 
312  /* OK to make connection */
313  conn = libpqsrv_connect(connstr, dblink_we_connect);
314 
315  if (PQstatus(conn) == CONNECTION_BAD)
316  {
317  msg = pchomp(PQerrorMessage(conn));
318  libpqsrv_disconnect(conn);
319  if (rconn)
320  pfree(rconn);
321 
322  ereport(ERROR,
323  (errcode(ERRCODE_SQLCLIENT_UNABLE_TO_ESTABLISH_SQLCONNECTION),
324  errmsg("could not establish connection"),
325  errdetail_internal("%s", msg)));
326  }
327 
328  /* check password actually used if not superuser */
329  dblink_security_check(conn, rconn, connstr);
330 
331  /* attempt to set client encoding to match server encoding, if needed */
332  if (PQclientEncoding(conn) != GetDatabaseEncoding())
333  PQsetClientEncoding(conn, GetDatabaseEncodingName());
334 
335  if (connname)
336  {
337  rconn->conn = conn;
338  createNewConnection(connname, rconn);
339  }
340  else
341  {
342  if (pconn->conn)
343  libpqsrv_disconnect(pconn->conn);
344  pconn->conn = conn;
345  }
346 
347  PG_RETURN_TEXT_P(cstring_to_text("OK"));
348 }
349 
350 /*
351  * Clear a persistent connection to another database
352  */
353 PG_FUNCTION_INFO_V1(dblink_disconnect);
354 Datum
355 dblink_disconnect(PG_FUNCTION_ARGS)
356 {
357  char *conname = NULL;
358  remoteConn *rconn = NULL;
359  PGconn *conn = NULL;
360 
361  dblink_init();
362 
363  if (PG_NARGS() == 1)
364  {
365  conname = text_to_cstring(PG_GETARG_TEXT_PP(0));
366  rconn = getConnectionByName(conname);
367  if (rconn)
368  conn = rconn->conn;
369  }
370  else
371  conn = pconn->conn;
372 
373  if (!conn)
374  dblink_conn_not_avail(conname);
375 
376  libpqsrv_disconnect(conn);
377  if (rconn)
378  {
379  deleteConnection(conname);
380  pfree(rconn);
381  }
382  else
383  pconn->conn = NULL;
384 
385  PG_RETURN_TEXT_P(cstring_to_text("OK"));
386 }
387 
388 /*
389  * opens a cursor using a persistent connection
390  */
391 PG_FUNCTION_INFO_V1(dblink_open);
392 Datum
393 dblink_open(PG_FUNCTION_ARGS)
394 {
395  PGresult *res = NULL;
396  PGconn *conn;
397  char *curname = NULL;
398  char *sql = NULL;
399  char *conname = NULL;
400  StringInfoData buf;
401  remoteConn *rconn = NULL;
402  bool fail = true; /* default to backward compatible behavior */
403 
404  dblink_init();
405  initStringInfo(&buf);
406 
407  if (PG_NARGS() == 2)
408  {
409  /* text,text */
410  curname = text_to_cstring(PG_GETARG_TEXT_PP(0));
411  sql = text_to_cstring(PG_GETARG_TEXT_PP(1));
412  rconn = pconn;
413  }
414  else if (PG_NARGS() == 3)
415  {
416  /* might be text,text,text or text,text,bool */
417  if (get_fn_expr_argtype(fcinfo->flinfo, 2) == BOOLOID)
418  {
419  curname = text_to_cstring(PG_GETARG_TEXT_PP(0));
420  sql = text_to_cstring(PG_GETARG_TEXT_PP(1));
421  fail = PG_GETARG_BOOL(2);
422  rconn = pconn;
423  }
424  else
425  {
426  conname = text_to_cstring(PG_GETARG_TEXT_PP(0));
427  curname = text_to_cstring(PG_GETARG_TEXT_PP(1));
428  sql = text_to_cstring(PG_GETARG_TEXT_PP(2));
429  rconn = getConnectionByName(conname);
430  }
431  }
432  else if (PG_NARGS() == 4)
433  {
434  /* text,text,text,bool */
435  conname = text_to_cstring(PG_GETARG_TEXT_PP(0));
436  curname = text_to_cstring(PG_GETARG_TEXT_PP(1));
437  sql = text_to_cstring(PG_GETARG_TEXT_PP(2));
438  fail = PG_GETARG_BOOL(3);
439  rconn = getConnectionByName(conname);
440  }
441 
442  if (!rconn || !rconn->conn)
443  dblink_conn_not_avail(conname);
444 
445  conn = rconn->conn;
446 
447  /* If we are not in a transaction, start one */
448  if (PQtransactionStatus(conn) == PQTRANS_IDLE)
449  {
450  res = libpqsrv_exec(conn, "BEGIN", dblink_we_get_result);
451  if (PQresultStatus(res) != PGRES_COMMAND_OK)
452  dblink_res_internalerror(conn, res, "begin error");
453  PQclear(res);
454  rconn->newXactForCursor = true;
455 
456  /*
457  * Since transaction state was IDLE, we force cursor count to
458  * initially be 0. This is needed as a previous ABORT might have wiped
459  * out our transaction without maintaining the cursor count for us.
460  */
461  rconn->openCursorCount = 0;
462  }
463 
464  /* if we started a transaction, increment cursor count */
465  if (rconn->newXactForCursor)
466  (rconn->openCursorCount)++;
467 
468  appendStringInfo(&buf, "DECLARE %s CURSOR FOR %s", curname, sql);
469  res = libpqsrv_exec(conn, buf.data, dblink_we_get_result);
470  if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
471  {
472  dblink_res_error(conn, conname, res, fail,
473  "while opening cursor \"%s\"", curname);
474  PG_RETURN_TEXT_P(cstring_to_text("ERROR"));
475  }
476 
477  PQclear(res);
478  PG_RETURN_TEXT_P(cstring_to_text("OK"));
479 }
480 
481 /*
482  * closes a cursor
483  */
484 PG_FUNCTION_INFO_V1(dblink_close);
485 Datum
486 dblink_close(PG_FUNCTION_ARGS)
487 {
488  PGconn *conn;
489  PGresult *res = NULL;
490  char *curname = NULL;
491  char *conname = NULL;
492  StringInfoData buf;
493  remoteConn *rconn = NULL;
494  bool fail = true; /* default to backward compatible behavior */
495 
496  dblink_init();
497  initStringInfo(&buf);
498 
499  if (PG_NARGS() == 1)
500  {
501  /* text */
502  curname = text_to_cstring(PG_GETARG_TEXT_PP(0));
503  rconn = pconn;
504  }
505  else if (PG_NARGS() == 2)
506  {
507  /* might be text,text or text,bool */
508  if (get_fn_expr_argtype(fcinfo->flinfo, 1) == BOOLOID)
509  {
510  curname = text_to_cstring(PG_GETARG_TEXT_PP(0));
511  fail = PG_GETARG_BOOL(1);
512  rconn = pconn;
513  }
514  else
515  {
516  conname = text_to_cstring(PG_GETARG_TEXT_PP(0));
517  curname = text_to_cstring(PG_GETARG_TEXT_PP(1));
518  rconn = getConnectionByName(conname);
519  }
520  }
521  if (PG_NARGS() == 3)
522  {
523  /* text,text,bool */
524  conname = text_to_cstring(PG_GETARG_TEXT_PP(0));
525  curname = text_to_cstring(PG_GETARG_TEXT_PP(1));
526  fail = PG_GETARG_BOOL(2);
527  rconn = getConnectionByName(conname);
528  }
529 
530  if (!rconn || !rconn->conn)
531  dblink_conn_not_avail(conname);
532 
533  conn = rconn->conn;
534 
535  appendStringInfo(&buf, "CLOSE %s", curname);
536 
537  /* close the cursor */
538  res = libpqsrv_exec(conn, buf.data, dblink_we_get_result);
539  if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
540  {
541  dblink_res_error(conn, conname, res, fail,
542  "while closing cursor \"%s\"", curname);
543  PG_RETURN_TEXT_P(cstring_to_text("ERROR"));
544  }
545 
546  PQclear(res);
547 
548  /* if we started a transaction, decrement cursor count */
549  if (rconn->newXactForCursor)
550  {
551  (rconn->openCursorCount)--;
552 
553  /* if count is zero, commit the transaction */
554  if (rconn->openCursorCount == 0)
555  {
556  rconn->newXactForCursor = false;
557 
558  res = libpqsrv_exec(conn, "COMMIT", dblink_we_get_result);
559  if (PQresultStatus(res) != PGRES_COMMAND_OK)
560  dblink_res_internalerror(conn, res, "commit error");
561  PQclear(res);
562  }
563  }
564 
565  PG_RETURN_TEXT_P(cstring_to_text("OK"));
566 }
567 
568 /*
569  * Fetch results from an open cursor
570  */
571 PG_FUNCTION_INFO_V1(dblink_fetch);
572 Datum
573 dblink_fetch(PG_FUNCTION_ARGS)
574 {
575  PGresult *res = NULL;
576  char *conname = NULL;
577  remoteConn *rconn = NULL;
578  PGconn *conn = NULL;
579  StringInfoData buf;
580  char *curname = NULL;
581  int howmany = 0;
582  bool fail = true; /* default to backward compatible */
583 
584  prepTuplestoreResult(fcinfo);
585 
586  dblink_init();
587 
588  if (PG_NARGS() == 4)
589  {
590  /* text,text,int,bool */
591  conname = text_to_cstring(PG_GETARG_TEXT_PP(0));
592  curname = text_to_cstring(PG_GETARG_TEXT_PP(1));
593  howmany = PG_GETARG_INT32(2);
594  fail = PG_GETARG_BOOL(3);
595 
596  rconn = getConnectionByName(conname);
597  if (rconn)
598  conn = rconn->conn;
599  }
600  else if (PG_NARGS() == 3)
601  {
602  /* text,text,int or text,int,bool */
603  if (get_fn_expr_argtype(fcinfo->flinfo, 2) == BOOLOID)
604  {
605  curname = text_to_cstring(PG_GETARG_TEXT_PP(0));
606  howmany = PG_GETARG_INT32(1);
607  fail = PG_GETARG_BOOL(2);
608  conn = pconn->conn;
609  }
610  else
611  {
612  conname = text_to_cstring(PG_GETARG_TEXT_PP(0));
613  curname = text_to_cstring(PG_GETARG_TEXT_PP(1));
614  howmany = PG_GETARG_INT32(2);
615 
616  rconn = getConnectionByName(conname);
617  if (rconn)
618  conn = rconn->conn;
619  }
620  }
621  else if (PG_NARGS() == 2)
622  {
623  /* text,int */
624  curname = text_to_cstring(PG_GETARG_TEXT_PP(0));
625  howmany = PG_GETARG_INT32(1);
626  conn = pconn->conn;
627  }
628 
629  if (!conn)
630  dblink_conn_not_avail(conname);
631 
632  initStringInfo(&buf);
633  appendStringInfo(&buf, "FETCH %d FROM %s", howmany, curname);
634 
635  /*
636  * Try to execute the query. Note that since libpq uses malloc, the
637  * PGresult will be long-lived even though we are still in a short-lived
638  * memory context.
639  */
640  res = libpqsrv_exec(conn, buf.data, dblink_we_get_result);
641  if (!res ||
642  (PQresultStatus(res) != PGRES_COMMAND_OK &&
643  PQresultStatus(res) != PGRES_TUPLES_OK))
644  {
645  dblink_res_error(conn, conname, res, fail,
646  "while fetching from cursor \"%s\"", curname);
647  return (Datum) 0;
648  }
649  else if (PQresultStatus(res) == PGRES_COMMAND_OK)
650  {
651  /* cursor does not exist - closed already or bad name */
652  PQclear(res);
653  ereport(ERROR,
654  (errcode(ERRCODE_INVALID_CURSOR_NAME),
655  errmsg("cursor \"%s\" does not exist", curname)));
656  }
657 
658  materializeResult(fcinfo, conn, res);
659  return (Datum) 0;
660 }
661 
662 /*
663  * Note: this is the new preferred version of dblink
664  */
665 PG_FUNCTION_INFO_V1(dblink_record);
666 Datum
667 dblink_record(PG_FUNCTION_ARGS)
668 {
669  return dblink_record_internal(fcinfo, false);
670 }
671 
672 PG_FUNCTION_INFO_V1(dblink_send_query);
673 Datum
674 dblink_send_query(PG_FUNCTION_ARGS)
675 {
676  PGconn *conn;
677  char *sql;
678  int retval;
679 
680  if (PG_NARGS() == 2)
681  {
682  conn = dblink_get_named_conn(text_to_cstring(PG_GETARG_TEXT_PP(0)));
683  sql = text_to_cstring(PG_GETARG_TEXT_PP(1));
684  }
685  else
686  /* shouldn't happen */
687  elog(ERROR, "wrong number of arguments");
688 
689  /* async query send */
690  retval = PQsendQuery(conn, sql);
691  if (retval != 1)
692  elog(NOTICE, "could not send query: %s", pchomp(PQerrorMessage(conn)));
693 
694  PG_RETURN_INT32(retval);
695 }
696 
697 PG_FUNCTION_INFO_V1(dblink_get_result);
698 Datum
699 dblink_get_result(PG_FUNCTION_ARGS)
700 {
701  return dblink_record_internal(fcinfo, true);
702 }
703 
704 static Datum
705 dblink_record_internal(FunctionCallInfo fcinfo, bool is_async)
706 {
707  PGconn *volatile conn = NULL;
708  volatile bool freeconn = false;
709 
710  prepTuplestoreResult(fcinfo);
711 
712  dblink_init();
713 
714  PG_TRY();
715  {
716  char *sql = NULL;
717  char *conname = NULL;
718  bool fail = true; /* default to backward compatible */
719 
720  if (!is_async)
721  {
722  if (PG_NARGS() == 3)
723  {
724  /* text,text,bool */
725  conname = text_to_cstring(PG_GETARG_TEXT_PP(0));
726  sql = text_to_cstring(PG_GETARG_TEXT_PP(1));
727  fail = PG_GETARG_BOOL(2);
728  dblink_get_conn(conname, &conn, &conname, &freeconn);
729  }
730  else if (PG_NARGS() == 2)
731  {
732  /* text,text or text,bool */
733  if (get_fn_expr_argtype(fcinfo->flinfo, 1) == BOOLOID)
734  {
735  sql = text_to_cstring(PG_GETARG_TEXT_PP(0));
736  fail = PG_GETARG_BOOL(1);
737  conn = pconn->conn;
738  }
739  else
740  {
741  conname = text_to_cstring(PG_GETARG_TEXT_PP(0));
742  sql = text_to_cstring(PG_GETARG_TEXT_PP(1));
743  dblink_get_conn(conname, &conn, &conname, &freeconn);
744  }
745  }
746  else if (PG_NARGS() == 1)
747  {
748  /* text */
749  conn = pconn->conn;
750  sql = text_to_cstring(PG_GETARG_TEXT_PP(0));
751  }
752  else
753  /* shouldn't happen */
754  elog(ERROR, "wrong number of arguments");
755  }
756  else /* is_async */
757  {
758  /* get async result */
759  conname = text_to_cstring(PG_GETARG_TEXT_PP(0));
760 
761  if (PG_NARGS() == 2)
762  {
763  /* text,bool */
764  fail = PG_GETARG_BOOL(1);
765  conn = dblink_get_named_conn(conname);
766  }
767  else if (PG_NARGS() == 1)
768  {
769  /* text */
770  conn = dblink_get_named_conn(conname);
771  }
772  else
773  /* shouldn't happen */
774  elog(ERROR, "wrong number of arguments");
775  }
776 
777  if (!conn)
778  dblink_conn_not_avail(conname);
779 
780  if (!is_async)
781  {
782  /* synchronous query, use efficient tuple collection method */
783  materializeQueryResult(fcinfo, conn, conname, sql, fail);
784  }
785  else
786  {
787  /* async result retrieval, do it the old way */
788  PGresult *res = libpqsrv_get_result(conn, dblink_we_get_result);
789 
790  /* NULL means we're all done with the async results */
791  if (res)
792  {
793  if (PQresultStatus(res) != PGRES_COMMAND_OK &&
794  PQresultStatus(res) != PGRES_TUPLES_OK)
795  {
796  dblink_res_error(conn, conname, res, fail,
797  "while executing query");
798  /* if fail isn't set, we'll return an empty query result */
799  }
800  else
801  {
802  materializeResult(fcinfo, conn, res);
803  }
804  }
805  }
806  }
807  PG_FINALLY();
808  {
809  /* if needed, close the connection to the database */
810  if (freeconn)
811  libpqsrv_disconnect(conn);
812  }
813  PG_END_TRY();
814 
815  return (Datum) 0;
816 }
817 
818 /*
819  * Verify function caller can handle a tuplestore result, and set up for that.
820  *
821  * Note: if the caller returns without actually creating a tuplestore, the
822  * executor will treat the function result as an empty set.
823  */
824 static void
825 prepTuplestoreResult(FunctionCallInfo fcinfo)
826 {
827  ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
828 
829  /* check to see if query supports us returning a tuplestore */
830  if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
831  ereport(ERROR,
832  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
833  errmsg("set-valued function called in context that cannot accept a set")));
834  if (!(rsinfo->allowedModes & SFRM_Materialize))
835  ereport(ERROR,
836  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
837  errmsg("materialize mode required, but it is not allowed in this context")));
838 
839  /* let the executor know we're sending back a tuplestore */
840  rsinfo->returnMode = SFRM_Materialize;
841 
842  /* caller must fill these to return a non-empty result */
843  rsinfo->setResult = NULL;
844  rsinfo->setDesc = NULL;
845 }
846 
847 /*
848  * Copy the contents of the PGresult into a tuplestore to be returned
849  * as the result of the current function.
850  * The PGresult will be released in this function.
851  */
852 static void
853 materializeResult(FunctionCallInfo fcinfo, PGconn *conn, PGresult *res)
854 {
855  ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
856 
857  /* prepTuplestoreResult must have been called previously */
858  Assert(rsinfo->returnMode == SFRM_Materialize);
859 
860  PG_TRY();
861  {
862  TupleDesc tupdesc;
863  bool is_sql_cmd;
864  int ntuples;
865  int nfields;
866 
867  if (PQresultStatus(res) == PGRES_COMMAND_OK)
868  {
869  is_sql_cmd = true;
870 
871  /*
872  * need a tuple descriptor representing one TEXT column to return
873  * the command status string as our result tuple
874  */
875  tupdesc = CreateTemplateTupleDesc(1);
876  TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
877  TEXTOID, -1, 0);
878  ntuples = 1;
879  nfields = 1;
880  }
881  else
882  {
883  Assert(PQresultStatus(res) == PGRES_TUPLES_OK);
884 
885  is_sql_cmd = false;
886 
887  /* get a tuple descriptor for our result type */
888  switch (get_call_result_type(fcinfo, NULL, &tupdesc))
889  {
890  case TYPEFUNC_COMPOSITE:
891  /* success */
892  break;
893  case TYPEFUNC_RECORD:
894  /* failed to determine actual type of RECORD */
895  ereport(ERROR,
896  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
897  errmsg("function returning record called in context "
898  "that cannot accept type record")));
899  break;
900  default:
901  /* result type isn't composite */
902  elog(ERROR, "return type must be a row type");
903  break;
904  }
905 
906  /* make sure we have a persistent copy of the tupdesc */
907  tupdesc = CreateTupleDescCopy(tupdesc);
908  ntuples = PQntuples(res);
909  nfields = PQnfields(res);
910  }
911 
912  /*
913  * check result and tuple descriptor have the same number of columns
914  */
915  if (nfields != tupdesc->natts)
916  ereport(ERROR,
917  (errcode(ERRCODE_DATATYPE_MISMATCH),
918  errmsg("remote query result rowtype does not match "
919  "the specified FROM clause rowtype")));
920 
921  if (ntuples > 0)
922  {
923  AttInMetadata *attinmeta;
924  int nestlevel = -1;
925  Tuplestorestate *tupstore;
926  MemoryContext oldcontext;
927  int row;
928  char **values;
929 
930  attinmeta = TupleDescGetAttInMetadata(tupdesc);
931 
932  /* Set GUCs to ensure we read GUC-sensitive data types correctly */
933  if (!is_sql_cmd)
934  nestlevel = applyRemoteGucs(conn);
935 
936  oldcontext = MemoryContextSwitchTo(rsinfo->econtext->ecxt_per_query_memory);
937  tupstore = tuplestore_begin_heap(true, false, work_mem);
938  rsinfo->setResult = tupstore;
939  rsinfo->setDesc = tupdesc;
940  MemoryContextSwitchTo(oldcontext);
941 
942  values = palloc_array(char *, nfields);
943 
944  /* put all tuples into the tuplestore */
945  for (row = 0; row < ntuples; row++)
946  {
947  HeapTuple tuple;
948 
949  if (!is_sql_cmd)
950  {
951  int i;
952 
953  for (i = 0; i < nfields; i++)
954  {
955  if (PQgetisnull(res, row, i))
956  values[i] = NULL;
957  else
958  values[i] = PQgetvalue(res, row, i);
959  }
960  }
961  else
962  {
963  values[0] = PQcmdStatus(res);
964  }
965 
966  /* build the tuple and put it into the tuplestore. */
967  tuple = BuildTupleFromCStrings(attinmeta, values);
968  tuplestore_puttuple(tupstore, tuple);
969  }
970 
971  /* clean up GUC settings, if we changed any */
972  restoreLocalGucs(nestlevel);
973  }
974  }
975  PG_FINALLY();
976  {
977  /* be sure to release the libpq result */
978  PQclear(res);
979  }
980  PG_END_TRY();
981 }
982 
983 /*
984  * Execute the given SQL command and store its results into a tuplestore
985  * to be returned as the result of the current function.
986  *
987  * This is equivalent to PQexec followed by materializeResult, but we make
988  * use of libpq's single-row mode to avoid accumulating the whole result
989  * inside libpq before it gets transferred to the tuplestore.
990  */
991 static void
992 materializeQueryResult(FunctionCallInfo fcinfo,
993  PGconn *conn,
994  const char *conname,
995  const char *sql,
996  bool fail)
997 {
998  ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
999  PGresult *volatile res = NULL;
1000  volatile storeInfo sinfo = {0};
1001 
1002  /* prepTuplestoreResult must have been called previously */
1003  Assert(rsinfo->returnMode == SFRM_Materialize);
1004 
1005  sinfo.fcinfo = fcinfo;
1006 
1007  PG_TRY();
1008  {
1009  /* Create short-lived memory context for data conversions */
1010  sinfo.tmpcontext = AllocSetContextCreate(CurrentMemoryContext,
1011  "dblink temporary context",
1012  ALLOCSET_DEFAULT_SIZES);
1013 
1014  /* execute query, collecting any tuples into the tuplestore */
1015  res = storeQueryResult(&sinfo, conn, sql);
1016 
1017  if (!res ||
1018  (PQresultStatus(res) != PGRES_COMMAND_OK &&
1019  PQresultStatus(res) != PGRES_TUPLES_OK))
1020  {
1021  /*
1022  * dblink_res_error will clear the passed PGresult, so we need
1023  * this ugly dance to avoid doing so twice during error exit
1024  */
1025  PGresult *res1 = res;
1026 
1027  res = NULL;
1028  dblink_res_error(conn, conname, res1, fail,
1029  "while executing query");
1030  /* if fail isn't set, we'll return an empty query result */
1031  }
1032  else if (PQresultStatus(res) == PGRES_COMMAND_OK)
1033  {
1034  /*
1035  * storeRow didn't get called, so we need to convert the command
1036  * status string to a tuple manually
1037  */
1038  TupleDesc tupdesc;
1039  AttInMetadata *attinmeta;
1040  Tuplestorestate *tupstore;
1041  HeapTuple tuple;
1042  char *values[1];
1043  MemoryContext oldcontext;
1044 
1045  /*
1046  * need a tuple descriptor representing one TEXT column to return
1047  * the command status string as our result tuple
1048  */
1049  tupdesc = CreateTemplateTupleDesc(1);
1050  TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
1051  TEXTOID, -1, 0);
1052  attinmeta = TupleDescGetAttInMetadata(tupdesc);
1053 
1054  oldcontext = MemoryContextSwitchTo(rsinfo->econtext->ecxt_per_query_memory);
1055  tupstore = tuplestore_begin_heap(true, false, work_mem);
1056  rsinfo->setResult = tupstore;
1057  rsinfo->setDesc = tupdesc;
1058  MemoryContextSwitchTo(oldcontext);
1059 
1060  values[0] = PQcmdStatus(res);
1061 
1062  /* build the tuple and put it into the tuplestore. */
1063  tuple = BuildTupleFromCStrings(attinmeta, values);
1064  tuplestore_puttuple(tupstore, tuple);
1065 
1066  PQclear(res);
1067  res = NULL;
1068  }
1069  else
1070  {
1071  Assert(PQresultStatus(res) == PGRES_TUPLES_OK);
1072  /* storeRow should have created a tuplestore */
1073  Assert(rsinfo->setResult != NULL);
1074 
1075  PQclear(res);
1076  res = NULL;
1077  }
1078 
1079  /* clean up data conversion short-lived memory context */
1080  if (sinfo.tmpcontext != NULL)
1081  MemoryContextDelete(sinfo.tmpcontext);
1082  sinfo.tmpcontext = NULL;
1083 
1084  PQclear(sinfo.last_res);
1085  sinfo.last_res = NULL;
1086  PQclear(sinfo.cur_res);
1087  sinfo.cur_res = NULL;
1088  }
1089  PG_CATCH();
1090  {
1091  /* be sure to release any libpq result we collected */
1092  PQclear(res);
1093  PQclear(sinfo.last_res);
1094  PQclear(sinfo.cur_res);
1095  /* and clear out any pending data in libpq */
1096  while ((res = libpqsrv_get_result(conn, dblink_we_get_result)) !=
1097  NULL)
1098  PQclear(res);
1099  PG_RE_THROW();
1100  }
1101  PG_END_TRY();
1102 }
1103 
1104 /*
1105  * Execute query, and send any result rows to sinfo->tuplestore.
1106  */
1107 static PGresult *
1108 storeQueryResult(volatile storeInfo *sinfo, PGconn *conn, const char *sql)
1109 {
1110  bool first = true;
1111  int nestlevel = -1;
1112  PGresult *res;
1113 
1114  if (!PQsendQuery(conn, sql))
1115  elog(ERROR, "could not send query: %s", pchomp(PQerrorMessage(conn)));
1116 
1117  if (!PQsetSingleRowMode(conn)) /* shouldn't fail */
1118  elog(ERROR, "failed to set single-row mode for dblink query");
1119 
1120  for (;;)
1121  {
1122  CHECK_FOR_INTERRUPTS();
1123 
1124  sinfo->cur_res = libpqsrv_get_result(conn, dblink_we_get_result);
1125  if (!sinfo->cur_res)
1126  break;
1127 
1128  if (PQresultStatus(sinfo->cur_res) == PGRES_SINGLE_TUPLE)
1129  {
1130  /* got one row from possibly-bigger resultset */
1131 
1132  /*
1133  * Set GUCs to ensure we read GUC-sensitive data types correctly.
1134  * We shouldn't do this until we have a row in hand, to ensure
1135  * libpq has seen any earlier ParameterStatus protocol messages.
1136  */
1137  if (first && nestlevel < 0)
1138  nestlevel = applyRemoteGucs(conn);
1139 
1140  storeRow(sinfo, sinfo->cur_res, first);
1141 
1142  PQclear(sinfo->cur_res);
1143  sinfo->cur_res = NULL;
1144  first = false;
1145  }
1146  else
1147  {
1148  /* if empty resultset, fill tuplestore header */
1149  if (first && PQresultStatus(sinfo->cur_res) == PGRES_TUPLES_OK)
1150  storeRow(sinfo, sinfo->cur_res, first);
1151 
1152  /* store completed result at last_res */
1153  PQclear(sinfo->last_res);
1154  sinfo->last_res = sinfo->cur_res;
1155  sinfo->cur_res = NULL;
1156  first = true;
1157  }
1158  }
1159 
1160  /* clean up GUC settings, if we changed any */
1161  restoreLocalGucs(nestlevel);
1162 
1163  /* return last_res */
1164  res = sinfo->last_res;
1165  sinfo->last_res = NULL;
1166  return res;
1167 }
1168 
1169 /*
1170  * Send single row to sinfo->tuplestore.
1171  *
1172  * If "first" is true, create the tuplestore using PGresult's metadata
1173  * (in this case the PGresult might contain either zero or one row).
1174  */
1175 static void
1176 storeRow(volatile storeInfo *sinfo, PGresult *res, bool first)
1177 {
1178  int nfields = PQnfields(res);
1179  HeapTuple tuple;
1180  int i;
1181  MemoryContext oldcontext;
1182 
1183  if (first)
1184  {
1185  /* Prepare for new result set */
1186  ReturnSetInfo *rsinfo = (ReturnSetInfo *) sinfo->fcinfo->resultinfo;
1187  TupleDesc tupdesc;
1188 
1189  /*
1190  * It's possible to get more than one result set if the query string
1191  * contained multiple SQL commands. In that case, we follow PQexec's
1192  * traditional behavior of throwing away all but the last result.
1193  */
1194  if (sinfo->tuplestore)
1195  tuplestore_end(sinfo->tuplestore);
1196  sinfo->tuplestore = NULL;
1197 
1198  /* get a tuple descriptor for our result type */
1199  switch (get_call_result_type(sinfo->fcinfo, NULL, &tupdesc))
1200  {
1201  case TYPEFUNC_COMPOSITE:
1202  /* success */
1203  break;
1204  case TYPEFUNC_RECORD:
1205  /* failed to determine actual type of RECORD */
1206  ereport(ERROR,
1207  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1208  errmsg("function returning record called in context "
1209  "that cannot accept type record")));
1210  break;
1211  default:
1212  /* result type isn't composite */
1213  elog(ERROR, "return type must be a row type");
1214  break;
1215  }
1216 
1217  /* make sure we have a persistent copy of the tupdesc */
1218  tupdesc = CreateTupleDescCopy(tupdesc);
1219 
1220  /* check result and tuple descriptor have the same number of columns */
1221  if (nfields != tupdesc->natts)
1222  ereport(ERROR,
1223  (errcode(ERRCODE_DATATYPE_MISMATCH),
1224  errmsg("remote query result rowtype does not match "
1225  "the specified FROM clause rowtype")));
1226 
1227  /* Prepare attinmeta for later data conversions */
1228  sinfo->attinmeta = TupleDescGetAttInMetadata(tupdesc);
1229 
1230  /* Create a new, empty tuplestore */
1231  oldcontext = MemoryContextSwitchTo(rsinfo->econtext->ecxt_per_query_memory);
1232  sinfo->tuplestore = tuplestore_begin_heap(true, false, work_mem);
1233  rsinfo->setResult = sinfo->tuplestore;
1234  rsinfo->setDesc = tupdesc;
1235  MemoryContextSwitchTo(oldcontext);
1236 
1237  /* Done if empty resultset */
1238  if (PQntuples(res) == 0)
1239  return;
1240 
1241  /*
1242  * Set up sufficiently-wide string pointers array; this won't change
1243  * in size so it's easy to preallocate.
1244  */
1245  if (sinfo->cstrs)
1246  pfree(sinfo->cstrs);
1247  sinfo->cstrs = palloc_array(char *, nfields);
1248  }
1249 
1250  /* Should have a single-row result if we get here */
1251  Assert(PQntuples(res) == 1);
1252 
1253  /*
1254  * Do the following work in a temp context that we reset after each tuple.
1255  * This cleans up not only the data we have direct access to, but any
1256  * cruft the I/O functions might leak.
1257  */
1258  oldcontext = MemoryContextSwitchTo(sinfo->tmpcontext);
1259 
1260  /*
1261  * Fill cstrs with null-terminated strings of column values.
1262  */
1263  for (i = 0; i < nfields; i++)
1264  {
1265  if (PQgetisnull(res, 0, i))
1266  sinfo->cstrs[i] = NULL;
1267  else
1268  sinfo->cstrs[i] = PQgetvalue(res, 0, i);
1269  }
1270 
1271  /* Convert row to a tuple, and add it to the tuplestore */
1272  tuple = BuildTupleFromCStrings(sinfo->attinmeta, sinfo->cstrs);
1273 
1274  tuplestore_puttuple(sinfo->tuplestore, tuple);
1275 
1276  /* Clean up */
1277  MemoryContextSwitchTo(oldcontext);
1278  MemoryContextReset(sinfo->tmpcontext);
1279 }
1280 
1281 /*
1282  * List all open dblink connections by name.
1283  * Returns an array of all connection names.
1284  * Takes no params
1285  */
1286 PG_FUNCTION_INFO_V1(dblink_get_connections);
1287 Datum
1288 dblink_get_connections(PG_FUNCTION_ARGS)
1289 {
1290  HASH_SEQ_STATUS status;
1291  remoteConnHashEnt *hentry;
1292  ArrayBuildState *astate = NULL;
1293 
1294  if (remoteConnHash)
1295  {
1296  hash_seq_init(&status, remoteConnHash);
1297  while ((hentry = (remoteConnHashEnt *) hash_seq_search(&status)) != NULL)
1298  {
1299  /* stash away current value */
1300  astate = accumArrayResult(astate,
1301  CStringGetTextDatum(hentry->name),
1302  false, TEXTOID, CurrentMemoryContext);
1303  }
1304  }
1305 
1306  if (astate)
1307  PG_RETURN_DATUM(makeArrayResult(astate,
1308  CurrentMemoryContext));
1309  else
1310  PG_RETURN_NULL();
1311 }
1312 
1313 /*
1314  * Checks if a given remote connection is busy
1315  *
1316  * Returns 1 if the connection is busy, 0 otherwise
1317  * Params:
1318  * text connection_name - name of the connection to check
1319  *
1320  */
1321 PG_FUNCTION_INFO_V1(dblink_is_busy);
1322 Datum
1323 dblink_is_busy(PG_FUNCTION_ARGS)
1324 {
1325  PGconn *conn;
1326 
1327  dblink_init();
1328  conn = dblink_get_named_conn(text_to_cstring(PG_GETARG_TEXT_PP(0)));
1329 
1330  PQconsumeInput(conn);
1331  PG_RETURN_INT32(PQisBusy(conn));
1332 }
1333 
1334 /*
1335  * Cancels a running request on a connection
1336  *
1337  * Returns text:
1338  * "OK" if the cancel request has been sent correctly,
1339  * an error message otherwise
1340  *
1341  * Params:
1342  * text connection_name - name of the connection to check
1343  *
1344  */
1345 PG_FUNCTION_INFO_V1(dblink_cancel_query);
1346 Datum
1347 dblink_cancel_query(PG_FUNCTION_ARGS)
1348 {
1349  PGconn *conn;
1350  const char *msg;
1351  TimestampTz endtime;
1352 
1353  dblink_init();
1354  conn = dblink_get_named_conn(text_to_cstring(PG_GETARG_TEXT_PP(0)));
1355  endtime = TimestampTzPlusMilliseconds(GetCurrentTimestamp(),
1356  30000);
1357  msg = libpqsrv_cancel(conn, endtime);
1358  if (msg == NULL)
1359  msg = "OK";
1360 
1361  PG_RETURN_TEXT_P(cstring_to_text(msg));
1362 }
1363 
1364 
1365 /*
1366  * Get error message from a connection
1367  *
1368  * Returns text:
1369  * "OK" if no error, an error message otherwise
1370  *
1371  * Params:
1372  * text connection_name - name of the connection to check
1373  *
1374  */
1375 PG_FUNCTION_INFO_V1(dblink_error_message);
1376 Datum
1377 dblink_error_message(PG_FUNCTION_ARGS)
1378 {
1379  char *msg;
1380  PGconn *conn;
1381 
1382  dblink_init();
1383  conn = dblink_get_named_conn(text_to_cstring(PG_GETARG_TEXT_PP(0)));
1384 
1385  msg = PQerrorMessage(conn);
1386  if (msg == NULL || msg[0] == '\0')
1387  PG_RETURN_TEXT_P(cstring_to_text("OK"));
1388  else
1389  PG_RETURN_TEXT_P(cstring_to_text(pchomp(msg)));
1390 }
1391 
1392 /*
1393  * Execute an SQL non-SELECT command
1394  */
1395 PG_FUNCTION_INFO_V1(dblink_exec);
1396 Datum
1397 dblink_exec(PG_FUNCTION_ARGS)
1398 {
1399  text *volatile sql_cmd_status = NULL;
1400  PGconn *volatile conn = NULL;
1401  volatile bool freeconn = false;
1402 
1403  dblink_init();
1404 
1405  PG_TRY();
1406  {
1407  PGresult *res = NULL;
1408  char *sql = NULL;
1409  char *conname = NULL;
1410  bool fail = true; /* default to backward compatible behavior */
1411 
1412  if (PG_NARGS() == 3)
1413  {
1414  /* must be text,text,bool */
1415  conname = text_to_cstring(PG_GETARG_TEXT_PP(0));
1416  sql = text_to_cstring(PG_GETARG_TEXT_PP(1));
1417  fail = PG_GETARG_BOOL(2);
1418  dblink_get_conn(conname, &conn, &conname, &freeconn);
1419  }
1420  else if (PG_NARGS() == 2)
1421  {
1422  /* might be text,text or text,bool */
1423  if (get_fn_expr_argtype(fcinfo->flinfo, 1) == BOOLOID)
1424  {
1425  sql = text_to_cstring(PG_GETARG_TEXT_PP(0));
1426  fail = PG_GETARG_BOOL(1);
1427  conn = pconn->conn;
1428  }
1429  else
1430  {
1431  conname = text_to_cstring(PG_GETARG_TEXT_PP(0));
1432  sql = text_to_cstring(PG_GETARG_TEXT_PP(1));
1433  dblink_get_conn(conname, &conn, &conname, &freeconn);
1434  }
1435  }
1436  else if (PG_NARGS() == 1)
1437  {
1438  /* must be single text argument */
1439  conn = pconn->conn;
1440  sql = text_to_cstring(PG_GETARG_TEXT_PP(0));
1441  }
1442  else
1443  /* shouldn't happen */
1444  elog(ERROR, "wrong number of arguments");
1445 
1446  if (!conn)
1447  dblink_conn_not_avail(conname);
1448 
1449  res = libpqsrv_exec(conn, sql, dblink_we_get_result);
1450  if (!res ||
1451  (PQresultStatus(res) != PGRES_COMMAND_OK &&
1452  PQresultStatus(res) != PGRES_TUPLES_OK))
1453  {
1454  dblink_res_error(conn, conname, res, fail,
1455  "while executing command");
1456 
1457  /*
1458  * and save a copy of the command status string to return as our
1459  * result tuple
1460  */
1461  sql_cmd_status = cstring_to_text("ERROR");
1462  }
1463  else if (PQresultStatus(res) == PGRES_COMMAND_OK)
1464  {
1465  /*
1466  * and save a copy of the command status string to return as our
1467  * result tuple
1468  */
1469  sql_cmd_status = cstring_to_text(PQcmdStatus(res));
1470  PQclear(res);
1471  }
1472  else
1473  {
1474  PQclear(res);
1475  ereport(ERROR,
1476  (errcode(ERRCODE_S_R_E_PROHIBITED_SQL_STATEMENT_ATTEMPTED),
1477  errmsg("statement returning results not allowed")));
1478  }
1479  }
1480  PG_FINALLY();
1481  {
1482  /* if needed, close the connection to the database */
1483  if (freeconn)
1484  libpqsrv_disconnect(conn);
1485  }
1486  PG_END_TRY();
1487 
1488  PG_RETURN_TEXT_P(sql_cmd_status);
1489 }
1490 
1491 
1492 /*
1493  * dblink_get_pkey
1494  *
1495  * Return list of primary key fields for the supplied relation,
1496  * or NULL if none exists.
1497  */
1498 PG_FUNCTION_INFO_V1(dblink_get_pkey);
1499 Datum
1500 dblink_get_pkey(PG_FUNCTION_ARGS)
1501 {
1502  int16 indnkeyatts;
1503  char **results;
1504  FuncCallContext *funcctx;
1505  int32 call_cntr;
1506  int32 max_calls;
1507  AttInMetadata *attinmeta;
1508  MemoryContext oldcontext;
1509 
1510  /* stuff done only on the first call of the function */
1511  if (SRF_IS_FIRSTCALL())
1512  {
1513  Relation rel;
1514  TupleDesc tupdesc;
1515 
1516  /* create a function context for cross-call persistence */
1517  funcctx = SRF_FIRSTCALL_INIT();
1518 
1519  /*
1520  * switch to memory context appropriate for multiple function calls
1521  */
1522  oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
1523 
1524  /* open target relation */
1525  rel = get_rel_from_relname(PG_GETARG_TEXT_PP(0), AccessShareLock, ACL_SELECT);
1526 
1527  /* get the array of attnums */
1528  results = get_pkey_attnames(rel, &indnkeyatts);
1529 
1530  relation_close(rel, AccessShareLock);
1531 
1532  /*
1533  * need a tuple descriptor representing one INT and one TEXT column
1534  */
1535  tupdesc = CreateTemplateTupleDesc(2);
1536  TupleDescInitEntry(tupdesc, (AttrNumber) 1, "position",
1537  INT4OID, -1, 0);
1538  TupleDescInitEntry(tupdesc, (AttrNumber) 2, "colname",
1539  TEXTOID, -1, 0);
1540 
1541  /*
1542  * Generate attribute metadata needed later to produce tuples from raw
1543  * C strings
1544  */
1545  attinmeta = TupleDescGetAttInMetadata(tupdesc);
1546  funcctx->attinmeta = attinmeta;
1547 
1548  if ((results != NULL) && (indnkeyatts > 0))
1549  {
1550  funcctx->max_calls = indnkeyatts;
1551 
1552  /* got results, keep track of them */
1553  funcctx->user_fctx = results;
1554  }
1555  else
1556  {
1557  /* fast track when no results */
1558  MemoryContextSwitchTo(oldcontext);
1559  SRF_RETURN_DONE(funcctx);
1560  }
1561 
1562  MemoryContextSwitchTo(oldcontext);
1563  }
1564 
1565  /* stuff done on every call of the function */
1566  funcctx = SRF_PERCALL_SETUP();
1567 
1568  /*
1569  * initialize per-call variables
1570  */
1571  call_cntr = funcctx->call_cntr;
1572  max_calls = funcctx->max_calls;
1573 
1574  results = (char **) funcctx->user_fctx;
1575  attinmeta = funcctx->attinmeta;
1576 
1577  if (call_cntr < max_calls) /* do when there is more left to send */
1578  {
1579  char **values;
1580  HeapTuple tuple;
1581  Datum result;
1582 
1583  values = palloc_array(char *, 2);
1584  values[0] = psprintf("%d", call_cntr + 1);
1585  values[1] = results[call_cntr];
1586 
1587  /* build the tuple */
1588  tuple = BuildTupleFromCStrings(attinmeta, values);
1589 
1590  /* make the tuple into a datum */
1591  result = HeapTupleGetDatum(tuple);
1592 
1593  SRF_RETURN_NEXT(funcctx, result);
1594  }
1595  else
1596  {
1597  /* do when there is no more left */
1598  SRF_RETURN_DONE(funcctx);
1599  }
1600 }
1601 
1602 
1603 /*
1604  * dblink_build_sql_insert
1605  *
1606  * Used to generate an SQL insert statement
1607  * based on an existing tuple in a local relation.
1608  * This is useful for selectively replicating data
1609  * to another server via dblink.
1610  *
1611  * API:
1612  * <relname> - name of local table of interest
1613  * <pkattnums> - an int2vector of attnums which will be used
1614  * to identify the local tuple of interest
1615  * <pknumatts> - number of attnums in pkattnums
1616  * <src_pkattvals_arry> - text array of key values which will be used
1617  * to identify the local tuple of interest
1618  * <tgt_pkattvals_arry> - text array of key values which will be used
1619  * to build the string for execution remotely. These are substituted
1620  * for their counterparts in src_pkattvals_arry
1621  */
1622 PG_FUNCTION_INFO_V1(dblink_build_sql_insert);
1623 Datum
1624 dblink_build_sql_insert(PG_FUNCTION_ARGS)
1625 {
1626  text *relname_text = PG_GETARG_TEXT_PP(0);
1627  int2vector *pkattnums_arg = (int2vector *) PG_GETARG_POINTER(1);
1628  int32 pknumatts_arg = PG_GETARG_INT32(2);
1629  ArrayType *src_pkattvals_arry = PG_GETARG_ARRAYTYPE_P(3);
1630  ArrayType *tgt_pkattvals_arry = PG_GETARG_ARRAYTYPE_P(4);
1631  Relation rel;
1632  int *pkattnums;
1633  int pknumatts;
1634  char **src_pkattvals;
1635  char **tgt_pkattvals;
1636  int src_nitems;
1637  int tgt_nitems;
1638  char *sql;
1639 
1640  /*
1641  * Open target relation.
1642  */
1643  rel = get_rel_from_relname(relname_text, AccessShareLock, ACL_SELECT);
1644 
1645  /*
1646  * Process pkattnums argument.
1647  */
1648  validate_pkattnums(rel, pkattnums_arg, pknumatts_arg,
1649  &pkattnums, &pknumatts);
1650 
1651  /*
1652  * Source array is made up of key values that will be used to locate the
1653  * tuple of interest from the local system.
1654  */
1655  src_pkattvals = get_text_array_contents(src_pkattvals_arry, &src_nitems);
1656 
1657  /*
1658  * There should be one source array key value for each key attnum
1659  */
1660  if (src_nitems != pknumatts)
1661  ereport(ERROR,
1662  (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
1663  errmsg("source key array length must match number of key attributes")));
1664 
1665  /*
1666  * Target array is made up of key values that will be used to build the
1667  * SQL string for use on the remote system.
1668  */
1669  tgt_pkattvals = get_text_array_contents(tgt_pkattvals_arry, &tgt_nitems);
1670 
1671  /*
1672  * There should be one target array key value for each key attnum
1673  */
1674  if (tgt_nitems != pknumatts)
1675  ereport(ERROR,
1676  (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
1677  errmsg("target key array length must match number of key attributes")));
1678 
1679  /*
1680  * Prep work is finally done. Go get the SQL string.
1681  */
1682  sql = get_sql_insert(rel, pkattnums, pknumatts, src_pkattvals, tgt_pkattvals);
1683 
1684  /*
1685  * Now we can close the relation.
1686  */
1687  relation_close(rel, AccessShareLock);
1688 
1689  /*
1690  * And send it
1691  */
1692  PG_RETURN_TEXT_P(cstring_to_text(sql));
1693 }
1694 
1695 
1696 /*
1697  * dblink_build_sql_delete
1698  *
1699  * Used to generate an SQL delete statement.
1700  * This is useful for selectively replicating a
1701  * delete to another server via dblink.
1702  *
1703  * API:
1704  * <relname> - name of remote table of interest
1705  * <pkattnums> - an int2vector of attnums which will be used
1706  * to identify the remote tuple of interest
1707  * <pknumatts> - number of attnums in pkattnums
1708  * <tgt_pkattvals_arry> - text array of key values which will be used
1709  * to build the string for execution remotely.
1710  */
1711 PG_FUNCTION_INFO_V1(dblink_build_sql_delete);
1712 Datum
1713 dblink_build_sql_delete(PG_FUNCTION_ARGS)
1714 {
1715  text *relname_text = PG_GETARG_TEXT_PP(0);
1716  int2vector *pkattnums_arg = (int2vector *) PG_GETARG_POINTER(1);
1717  int32 pknumatts_arg = PG_GETARG_INT32(2);
1718  ArrayType *tgt_pkattvals_arry = PG_GETARG_ARRAYTYPE_P(3);
1719  Relation rel;
1720  int *pkattnums;
1721  int pknumatts;
1722  char **tgt_pkattvals;
1723  int tgt_nitems;
1724  char *sql;
1725 
1726  /*
1727  * Open target relation.
1728  */
1729  rel = get_rel_from_relname(relname_text, AccessShareLock, ACL_SELECT);
1730 
1731  /*
1732  * Process pkattnums argument.
1733  */
1734  validate_pkattnums(rel, pkattnums_arg, pknumatts_arg,
1735  &pkattnums, &pknumatts);
1736 
1737  /*
1738  * Target array is made up of key values that will be used to build the
1739  * SQL string for use on the remote system.
1740  */
1741  tgt_pkattvals = get_text_array_contents(tgt_pkattvals_arry, &tgt_nitems);
1742 
1743  /*
1744  * There should be one target array key value for each key attnum
1745  */
1746  if (tgt_nitems != pknumatts)
1747  ereport(ERROR,
1748  (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
1749  errmsg("target key array length must match number of key attributes")));
1750 
1751  /*
1752  * Prep work is finally done. Go get the SQL string.
1753  */
1754  sql = get_sql_delete(rel, pkattnums, pknumatts, tgt_pkattvals);
1755 
1756  /*
1757  * Now we can close the relation.
1758  */
1759  relation_close(rel, AccessShareLock);
1760 
1761  /*
1762  * And send it
1763  */
1764  PG_RETURN_TEXT_P(cstring_to_text(sql));
1765 }
1766 
1767 
1768 /*
1769  * dblink_build_sql_update
1770  *
1771  * Used to generate an SQL update statement
1772  * based on an existing tuple in a local relation.
1773  * This is useful for selectively replicating data
1774  * to another server via dblink.
1775  *
1776  * API:
1777  * <relname> - name of local table of interest
1778  * <pkattnums> - an int2vector of attnums which will be used
1779  * to identify the local tuple of interest
1780  * <pknumatts> - number of attnums in pkattnums
1781  * <src_pkattvals_arry> - text array of key values which will be used
1782  * to identify the local tuple of interest
1783  * <tgt_pkattvals_arry> - text array of key values which will be used
1784  * to build the string for execution remotely. These are substituted
1785  * for their counterparts in src_pkattvals_arry
1786  */
1787 PG_FUNCTION_INFO_V1(dblink_build_sql_update);
1788 Datum
1789 dblink_build_sql_update(PG_FUNCTION_ARGS)
1790 {
1791  text *relname_text = PG_GETARG_TEXT_PP(0);
1792  int2vector *pkattnums_arg = (int2vector *) PG_GETARG_POINTER(1);
1793  int32 pknumatts_arg = PG_GETARG_INT32(2);
1794  ArrayType *src_pkattvals_arry = PG_GETARG_ARRAYTYPE_P(3);
1795  ArrayType *tgt_pkattvals_arry = PG_GETARG_ARRAYTYPE_P(4);
1796  Relation rel;
1797  int *pkattnums;
1798  int pknumatts;
1799  char **src_pkattvals;
1800  char **tgt_pkattvals;
1801  int src_nitems;
1802  int tgt_nitems;
1803  char *sql;
1804 
1805  /*
1806  * Open target relation.
1807  */
1808  rel = get_rel_from_relname(relname_text, AccessShareLock, ACL_SELECT);
1809 
1810  /*
1811  * Process pkattnums argument.
1812  */
1813  validate_pkattnums(rel, pkattnums_arg, pknumatts_arg,
1814  &pkattnums, &pknumatts);
1815 
1816  /*
1817  * Source array is made up of key values that will be used to locate the
1818  * tuple of interest from the local system.
1819  */
1820  src_pkattvals = get_text_array_contents(src_pkattvals_arry, &src_nitems);
1821 
1822  /*
1823  * There should be one source array key value for each key attnum
1824  */
1825  if (src_nitems != pknumatts)
1826  ereport(ERROR,
1827  (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
1828  errmsg("source key array length must match number of key attributes")));
1829 
1830  /*
1831  * Target array is made up of key values that will be used to build the
1832  * SQL string for use on the remote system.
1833  */
1834  tgt_pkattvals = get_text_array_contents(tgt_pkattvals_arry, &tgt_nitems);
1835 
1836  /*
1837  * There should be one target array key value for each key attnum
1838  */
1839  if (tgt_nitems != pknumatts)
1840  ereport(ERROR,
1841  (errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
1842  errmsg("target key array length must match number of key attributes")));
1843 
1844  /*
1845  * Prep work is finally done. Go get the SQL string.
1846  */
1847  sql = get_sql_update(rel, pkattnums, pknumatts, src_pkattvals, tgt_pkattvals);
1848 
1849  /*
1850  * Now we can close the relation.
1851  */
1852  relation_close(rel, AccessShareLock);
1853 
1854  /*
1855  * And send it
1856  */
1857  PG_RETURN_TEXT_P(cstring_to_text(sql));
1858 }
1859 
1860 /*
1861  * dblink_current_query
1862  * return the current query string
1863  * to allow its use in (among other things)
1864  * rewrite rules
1865  */
1866 PG_FUNCTION_INFO_V1(dblink_current_query);
1867 Datum
1868 dblink_current_query(PG_FUNCTION_ARGS)
1869 {
1870  /* This is now just an alias for the built-in function current_query() */
1871  PG_RETURN_DATUM(current_query(fcinfo));
1872 }
1873 
1874 /*
1875  * Retrieve async notifications for a connection.
1876  *
1877  * Returns a setof record of notifications, or an empty set if none received.
1878  * Can optionally take a named connection as parameter, but uses the unnamed
1879  * connection per default.
1880  *
1881  */
1882 #define DBLINK_NOTIFY_COLS 3
1883 
1884 PG_FUNCTION_INFO_V1(dblink_get_notify);
1885 Datum
1886 dblink_get_notify(PG_FUNCTION_ARGS)
1887 {
1888  PGconn *conn;
1889  PGnotify *notify;
1890  ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
1891 
1892  dblink_init();
1893  if (PG_NARGS() == 1)
1894  conn = dblink_get_named_conn(text_to_cstring(PG_GETARG_TEXT_PP(0)));
1895  else
1896  conn = pconn->conn;
1897 
1898  InitMaterializedSRF(fcinfo, 0);
1899 
1900  PQconsumeInput(conn);
1901  while ((notify = PQnotifies(conn)) != NULL)
1902  {
1903  Datum values[DBLINK_NOTIFY_COLS];
1904  bool nulls[DBLINK_NOTIFY_COLS];
1905 
1906  memset(values, 0, sizeof(values));
1907  memset(nulls, 0, sizeof(nulls));
1908 
1909  if (notify->relname != NULL)
1910  values[0] = CStringGetTextDatum(notify->relname);
1911  else
1912  nulls[0] = true;
1913 
1914  values[1] = Int32GetDatum(notify->be_pid);
1915 
1916  if (notify->extra != NULL)
1917  values[2] = CStringGetTextDatum(notify->extra);
1918  else
1919  nulls[2] = true;
1920 
1921  tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
1922 
1923  PQfreemem(notify);
1924  PQconsumeInput(conn);
1925  }
1926 
1927  return (Datum) 0;
1928 }
1929 
1930 /*
1931  * Validate the options given to a dblink foreign server or user mapping.
1932  * Raise an error if any option is invalid.
1933  *
1934  * We just check the names of options here, so semantic errors in options,
1935  * such as invalid numeric format, will be detected at the attempt to connect.
1936  */
1937 PG_FUNCTION_INFO_V1(dblink_fdw_validator);
1938 Datum
1939 dblink_fdw_validator(PG_FUNCTION_ARGS)
1940 {
1941  List *options_list = untransformRelOptions(PG_GETARG_DATUM(0));
1942  Oid context = PG_GETARG_OID(1);
1943  ListCell *cell;
1944 
1945  static const PQconninfoOption *options = NULL;
1946 
1947  /*
1948  * Get list of valid libpq options.
1949  *
1950  * To avoid unnecessary work, we get the list once and use it throughout
1951  * the lifetime of this backend process. We don't need to care about
1952  * memory context issues, because PQconndefaults allocates with malloc.
1953  */
1954  if (!options)
1955  {
1956  options = PQconndefaults();
1957  if (!options) /* assume reason for failure is OOM */
1958  ereport(ERROR,
1959  (errcode(ERRCODE_FDW_OUT_OF_MEMORY),
1960  errmsg("out of memory"),
1961  errdetail("Could not get libpq's default connection options.")));
1962  }
1963 
1964  /* Validate each supplied option. */
1965  foreach(cell, options_list)
1966  {
1967  DefElem *def = (DefElem *) lfirst(cell);
1968 
1969  if (!is_valid_dblink_option(options, def->defname, context))
1970  {
1971  /*
1972  * Unknown option, or invalid option for the context specified, so
1973  * complain about it. Provide a hint with a valid option that
1974  * looks similar, if there is one.
1975  */
1976  const PQconninfoOption *opt;
1977  const char *closest_match;
1978  ClosestMatchState match_state;
1979  bool has_valid_options = false;
1980 
1981  initClosestMatch(&match_state, def->defname, 4);
1982  for (opt = options; opt->keyword; opt++)
1983  {
1984  if (is_valid_dblink_option(options, opt->keyword, context))
1985  {
1986  has_valid_options = true;
1987  updateClosestMatch(&match_state, opt->keyword);
1988  }
1989  }
1990 
1991  closest_match = getClosestMatch(&match_state);
1992  ereport(ERROR,
1993  (errcode(ERRCODE_FDW_OPTION_NAME_NOT_FOUND),
1994  errmsg("invalid option \"%s\"", def->defname),
1995  has_valid_options ? closest_match ?
1996  errhint("Perhaps you meant the option \"%s\".",
1997  closest_match) : 0 :
1998  errhint("There are no valid options in this context.")));
1999  }
2000  }
2001 
2002  PG_RETURN_VOID();
2003 }
2004 
2005 
2006 /*************************************************************
2007  * internal functions
2008  */
2009 
2010 
2011 /*
2012  * get_pkey_attnames
2013  *
2014  * Get the primary key attnames for the given relation.
2015  * Return NULL, and set indnkeyatts = 0, if no primary key exists.
2016  */
2017 static char **
2018 get_pkey_attnames(Relation rel, int16 *indnkeyatts)
2019 {
2020  Relation indexRelation;
2021  ScanKeyData skey;
2022  SysScanDesc scan;
2023  HeapTuple indexTuple;
2024  int i;
2025  char **result = NULL;
2026  TupleDesc tupdesc;
2027 
2028  /* initialize indnkeyatts to 0 in case no primary key exists */
2029  *indnkeyatts = 0;
2030 
2031  tupdesc = rel->rd_att;
2032 
2033  /* Prepare to scan pg_index for entries having indrelid = this rel. */
2034  indexRelation = table_open(IndexRelationId, AccessShareLock);
2035  ScanKeyInit(&skey,
2036  Anum_pg_index_indrelid,
2037  BTEqualStrategyNumber, F_OIDEQ,
2038  ObjectIdGetDatum(RelationGetRelid(rel)));
2039 
2040  scan = systable_beginscan(indexRelation, IndexIndrelidIndexId, true,
2041  NULL, 1, &skey);
2042 
2043  while (HeapTupleIsValid(indexTuple = systable_getnext(scan)))
2044  {
2045  Form_pg_index index = (Form_pg_index) GETSTRUCT(indexTuple);
2046 
2047  /* we're only interested if it is the primary key */
2048  if (index->indisprimary)
2049  {
2050  *indnkeyatts = index->indnkeyatts;
2051  if (*indnkeyatts > 0)
2052  {
2053  result = palloc_array(char *, *indnkeyatts);
2054 
2055  for (i = 0; i < *indnkeyatts; i++)
2056  result[i] = SPI_fname(tupdesc, index->indkey.values[i]);
2057  }
2058  break;
2059  }
2060  }
2061 
2062  systable_endscan(scan);
2063  table_close(indexRelation, AccessShareLock);
2064 
2065  return result;
2066 }
2067 
2068 /*
2069  * Deconstruct a text[] into C-strings (note any NULL elements will be
2070  * returned as NULL pointers)
2071  */
2072 static char **
2073 get_text_array_contents(ArrayType *array, int *numitems)
2074 {
2075  int ndim = ARR_NDIM(array);
2076  int *dims = ARR_DIMS(array);
2077  int nitems;
2078  int16 typlen;
2079  bool typbyval;
2080  char typalign;
2081  char **values;
2082  char *ptr;
2083  bits8 *bitmap;
2084  int bitmask;
2085  int i;
2086 
2087  Assert(ARR_ELEMTYPE(array) == TEXTOID);
2088 
2089  *numitems = nitems = ArrayGetNItems(ndim, dims);
2090 
2091  get_typlenbyvalalign(ARR_ELEMTYPE(array),
2092  &typlen, &typbyval, &typalign);
2093 
2094  values = palloc_array(char *, nitems);
2095 
2096  ptr = ARR_DATA_PTR(array);
2097  bitmap = ARR_NULLBITMAP(array);
2098  bitmask = 1;
2099 
2100  for (i = 0; i < nitems; i++)
2101  {
2102  if (bitmap && (*bitmap & bitmask) == 0)
2103  {
2104  values[i] = NULL;
2105  }
2106  else
2107  {
2108  values[i] = TextDatumGetCString(PointerGetDatum(ptr));
2109  ptr = att_addlength_pointer(ptr, typlen, ptr);
2110  ptr = (char *) att_align_nominal(ptr, typalign);
2111  }
2112 
2113  /* advance bitmap pointer if any */
2114  if (bitmap)
2115  {
2116  bitmask <<= 1;
2117  if (bitmask == 0x100)
2118  {
2119  bitmap++;
2120  bitmask = 1;
2121  }
2122  }
2123  }
2124 
2125  return values;
2126 }
2127 
2128 static char *
2129 get_sql_insert(Relation rel, int *pkattnums, int pknumatts, char **src_pkattvals, char **tgt_pkattvals)
2130 {
2131  char *relname;
2132  HeapTuple tuple;
2133  TupleDesc tupdesc;
2134  int natts;
2135  StringInfoData buf;
2136  char *val;
2137  int key;
2138  int i;
2139  bool needComma;
2140 
2141  initStringInfo(&buf);
2142 
2143  /* get relation name including any needed schema prefix and quoting */
2144  relname = generate_relation_name(rel);
2145 
2146  tupdesc = rel->rd_att;
2147  natts = tupdesc->natts;
2148 
2149  tuple = get_tuple_of_interest(rel, pkattnums, pknumatts, src_pkattvals);
2150  if (!tuple)
2151  ereport(ERROR,
2152  (errcode(ERRCODE_CARDINALITY_VIOLATION),
2153  errmsg("source row not found")));
2154 
2155  appendStringInfo(&buf, "INSERT INTO %s(", relname);
2156 
2157  needComma = false;
2158  for (i = 0; i < natts; i++)
2159  {
2160  Form_pg_attribute att = TupleDescAttr(tupdesc, i);
2161 
2162  if (att->attisdropped)
2163  continue;
2164 
2165  if (needComma)
2166  appendStringInfoChar(&buf, ',');
2167 
2168  appendStringInfoString(&buf,
2169  quote_ident_cstr(NameStr(att->attname)));
2170  needComma = true;
2171  }
2172 
2173  appendStringInfoString(&buf, ") VALUES(");
2174 
2175  /*
2176  * Note: i is physical column number (counting from 0).
2177  */
2178  needComma = false;
2179  for (i = 0; i < natts; i++)
2180  {
2181  if (TupleDescAttr(tupdesc, i)->attisdropped)
2182  continue;
2183 
2184  if (needComma)
2185  appendStringInfoChar(&buf, ',');
2186 
2187  key = get_attnum_pk_pos(pkattnums, pknumatts, i);
2188 
2189  if (key >= 0)
2190  val = tgt_pkattvals[key] ? pstrdup(tgt_pkattvals[key]) : NULL;
2191  else
2192  val = SPI_getvalue(tuple, tupdesc, i + 1);
2193 
2194  if (val != NULL)
2195  {
2196  appendStringInfoString(&buf, quote_literal_cstr(val));
2197  pfree(val);
2198  }
2199  else
2200  appendStringInfoString(&buf, "NULL");
2201  needComma = true;
2202  }
2203  appendStringInfoChar(&buf, ')');
2204 
2205  return buf.data;
2206 }
2207 
2208 static char *
2209 get_sql_delete(Relation rel, int *pkattnums, int pknumatts, char **tgt_pkattvals)
2210 {
2211  char *relname;
2212  TupleDesc tupdesc;
2213  StringInfoData buf;
2214  int i;
2215 
2216  initStringInfo(&buf);
2217 
2218  /* get relation name including any needed schema prefix and quoting */
2219  relname = generate_relation_name(rel);
2220 
2221  tupdesc = rel->rd_att;
2222 
2223  appendStringInfo(&buf, "DELETE FROM %s WHERE ", relname);
2224  for (i = 0; i < pknumatts; i++)
2225  {
2226  int pkattnum = pkattnums[i];
2227  Form_pg_attribute attr = TupleDescAttr(tupdesc, pkattnum);
2228 
2229  if (i > 0)
2230  appendStringInfoString(&buf, " AND ");
2231 
2232  appendStringInfoString(&buf,
2233  quote_ident_cstr(NameStr(attr->attname)));
2234 
2235  if (tgt_pkattvals[i] != NULL)
2236  appendStringInfo(&buf, " = %s",
2237  quote_literal_cstr(tgt_pkattvals[i]));
2238  else
2239  appendStringInfoString(&buf, " IS NULL");
2240  }
2241 
2242  return buf.data;
2243 }
2244 
2245 static char *
2246 get_sql_update(Relation rel, int *pkattnums, int pknumatts, char **src_pkattvals, char **tgt_pkattvals)
2247 {
2248  char *relname;
2249  HeapTuple tuple;
2250  TupleDesc tupdesc;
2251  int natts;
2252  StringInfoData buf;
2253  char *val;
2254  int key;
2255  int i;
2256  bool needComma;
2257 
2258  initStringInfo(&buf);
2259 
2260  /* get relation name including any needed schema prefix and quoting */
2261  relname = generate_relation_name(rel);
2262 
2263  tupdesc = rel->rd_att;
2264  natts = tupdesc->natts;
2265 
2266  tuple = get_tuple_of_interest(rel, pkattnums, pknumatts, src_pkattvals);
2267  if (!tuple)
2268  ereport(ERROR,
2269  (errcode(ERRCODE_CARDINALITY_VIOLATION),
2270  errmsg("source row not found")));
2271 
2272  appendStringInfo(&buf, "UPDATE %s SET ", relname);
2273 
2274  /*
2275  * Note: i is physical column number (counting from 0).
2276  */
2277  needComma = false;
2278  for (i = 0; i < natts; i++)
2279  {
2280  Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
2281 
2282  if (attr->attisdropped)
2283  continue;
2284 
2285  if (needComma)
2286  appendStringInfoString(&buf, ", ");
2287 
2288  appendStringInfo(&buf, "%s = ",
2289  quote_ident_cstr(NameStr(attr->attname)));
2290 
2291  key = get_attnum_pk_pos(pkattnums, pknumatts, i);
2292 
2293  if (key >= 0)
2294  val = tgt_pkattvals[key] ? pstrdup(tgt_pkattvals[key]) : NULL;
2295  else
2296  val = SPI_getvalue(tuple, tupdesc, i + 1);
2297 
2298  if (val != NULL)
2299  {
2300  appendStringInfoString(&buf, quote_literal_cstr(val));
2301  pfree(val);
2302  }
2303  else
2304  appendStringInfoString(&buf, "NULL");
2305  needComma = true;
2306  }
2307 
2308  appendStringInfoString(&buf, " WHERE ");
2309 
2310  for (i = 0; i < pknumatts; i++)
2311  {
2312  int pkattnum = pkattnums[i];
2313  Form_pg_attribute attr = TupleDescAttr(tupdesc, pkattnum);
2314 
2315  if (i > 0)
2316  appendStringInfoString(&buf, " AND ");
2317 
2318  appendStringInfoString(&buf,
2319  quote_ident_cstr(NameStr(attr->attname)));
2320 
2321  val = tgt_pkattvals[i];
2322 
2323  if (val != NULL)
2324  appendStringInfo(&buf, " = %s", quote_literal_cstr(val));
2325  else
2326  appendStringInfoString(&buf, " IS NULL");
2327  }
2328 
2329  return buf.data;
2330 }
2331 
2332 /*
2333  * Return a properly quoted identifier.
2334  * Uses quote_ident in quote.c
2335  */
2336 static char *
2337 quote_ident_cstr(char *rawstr)
2338 {
2339  text *rawstr_text;
2340  text *result_text;
2341  char *result;
2342 
2343  rawstr_text = cstring_to_text(rawstr);
2344  result_text = DatumGetTextPP(DirectFunctionCall1(quote_ident,
2345  PointerGetDatum(rawstr_text)));
2346  result = text_to_cstring(result_text);
2347 
2348  return result;
2349 }
2350 
2351 static int
2352 get_attnum_pk_pos(int *pkattnums, int pknumatts, int key)
2353 {
2354  int i;
2355 
2356  /*
2357  * Not likely a long list anyway, so just scan for the value
2358  */
2359  for (i = 0; i < pknumatts; i++)
2360  if (key == pkattnums[i])
2361  return i;
2362 
2363  return -1;
2364 }
2365 
2366 static HeapTuple
2367 get_tuple_of_interest(Relation rel, int *pkattnums, int pknumatts, char **src_pkattvals)
2368 {
2369  char *relname;
2370  TupleDesc tupdesc;
2371  int natts;
2372  StringInfoData buf;
2373  int ret;
2374  HeapTuple tuple;
2375  int i;
2376 
2377  /*
2378  * Connect to SPI manager
2379  */
2380  SPI_connect();
2381 
2382  initStringInfo(&buf);
2383 
2384  /* get relation name including any needed schema prefix and quoting */
2385  relname = generate_relation_name(rel);
2386 
2387  tupdesc = rel->rd_att;
2388  natts = tupdesc->natts;
2389 
2390  /*
2391  * Build sql statement to look up tuple of interest, ie, the one matching
2392  * src_pkattvals. We used to use "SELECT *" here, but it's simpler to
2393  * generate a result tuple that matches the table's physical structure,
2394  * with NULLs for any dropped columns. Otherwise we have to deal with two
2395  * different tupdescs and everything's very confusing.
2396  */
2397  appendStringInfoString(&buf, "SELECT ");
2398 
2399  for (i = 0; i < natts; i++)
2400  {
2401  Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
2402 
2403  if (i > 0)
2404  appendStringInfoString(&buf, ", ");
2405 
2406  if (attr->attisdropped)
2407  appendStringInfoString(&buf, "NULL");
2408  else
2409  appendStringInfoString(&buf,
2410  quote_ident_cstr(NameStr(attr->attname)));
2411  }
2412 
2413  appendStringInfo(&buf, " FROM %s WHERE ", relname);
2414 
2415  for (i = 0; i < pknumatts; i++)
2416  {
2417  int pkattnum = pkattnums[i];
2418  Form_pg_attribute attr = TupleDescAttr(tupdesc, pkattnum);
2419 
2420  if (i > 0)
2421  appendStringInfoString(&buf, " AND ");
2422 
2423  appendStringInfoString(&buf,
2424  quote_ident_cstr(NameStr(attr->attname)));
2425 
2426  if (src_pkattvals[i] != NULL)
2427  appendStringInfo(&buf, " = %s",
2428  quote_literal_cstr(src_pkattvals[i]));
2429  else
2430  appendStringInfoString(&buf, " IS NULL");
2431  }
2432 
2433  /*
2434  * Retrieve the desired tuple
2435  */
2436  ret = SPI_exec(buf.data, 0);
2437  pfree(buf.data);
2438 
2439  /*
2440  * Only allow one qualifying tuple
2441  */
2442  if ((ret == SPI_OK_SELECT) && (SPI_processed > 1))
2443  ereport(ERROR,
2444  (errcode(ERRCODE_CARDINALITY_VIOLATION),
2445  errmsg("source criteria matched more than one record")));
2446 
2447  else if (ret == SPI_OK_SELECT && SPI_processed == 1)
2448  {
2449  SPITupleTable *tuptable = SPI_tuptable;
2450 
2451  tuple = SPI_copytuple(tuptable->vals[0]);
2452  SPI_finish();
2453 
2454  return tuple;
2455  }
2456  else
2457  {
2458  /*
2459  * no qualifying tuples
2460  */
2461  SPI_finish();
2462 
2463  return NULL;
2464  }
2465 
2466  /*
2467  * never reached, but keep compiler quiet
2468  */
2469  return NULL;
2470 }
2471 
2472 /*
2473  * Open the relation named by relname_text, acquire specified type of lock,
2474  * verify we have specified permissions.
2475  * Caller must close rel when done with it.
2476  */
2477 static Relation
2478 get_rel_from_relname(text *relname_text, LOCKMODE lockmode, AclMode aclmode)
2479 {
2480  RangeVar *relvar;
2481  Relation rel;
2482  AclResult aclresult;
2483 
2484  relvar = makeRangeVarFromNameList(textToQualifiedNameList(relname_text));
2485  rel = table_openrv(relvar, lockmode);
2486 
2487  aclresult = pg_class_aclcheck(RelationGetRelid(rel), GetUserId(),
2488  aclmode);
2489  if (aclresult != ACLCHECK_OK)
2490  aclcheck_error(aclresult, get_relkind_objtype(rel->rd_rel->relkind),
2491  RelationGetRelationName(rel));
2492 
2493  return rel;
2494 }
2495 
2496 /*
2497  * generate_relation_name - copied from ruleutils.c
2498  * Compute the name to display for a relation
2499  *
2500  * The result includes all necessary quoting and schema-prefixing.
2501  */
2502 static char *
2503 generate_relation_name(Relation rel)
2504 {
2505  char *nspname;
2506  char *result;
2507 
2508  /* Qualify the name if not visible in search path */
2509  if (RelationIsVisible(RelationGetRelid(rel)))
2510  nspname = NULL;
2511  else
2512  nspname = get_namespace_name(rel->rd_rel->relnamespace);
2513 
2514  result = quote_qualified_identifier(nspname, RelationGetRelationName(rel));
2515 
2516  return result;
2517 }
2518 
2519 
2520 static remoteConn *
2521 getConnectionByName(const char *name)
2522 {
2523  remoteConnHashEnt *hentry;
2524  char *key;
2525 
2526  if (!remoteConnHash)
2527  remoteConnHash = createConnHash();
2528 
2529  key = pstrdup(name);
2530  truncate_identifier(key, strlen(key), false);
2531  hentry = (remoteConnHashEnt *) hash_search(remoteConnHash,
2532  key, HASH_FIND, NULL);
2533 
2534  if (hentry)
2535  return hentry->rconn;
2536 
2537  return NULL;
2538 }
2539 
2540 static HTAB *
2541 createConnHash(void)
2542 {
2543  HASHCTL ctl;
2544 
2545  ctl.keysize = NAMEDATALEN;
2546  ctl.entrysize = sizeof(remoteConnHashEnt);
2547 
2548  return hash_create("Remote Con hash", NUMCONN, &ctl,
2549  HASH_ELEM | HASH_STRINGS);
2550 }
2551 
2552 static void
2553 createNewConnection(const char *name, remoteConn *rconn)
2554 {
2555  remoteConnHashEnt *hentry;
2556  bool found;
2557  char *key;
2558 
2559  if (!remoteConnHash)
2560  remoteConnHash = createConnHash();
2561 
2562  key = pstrdup(name);
2563  truncate_identifier(key, strlen(key), true);
2564  hentry = (remoteConnHashEnt *) hash_search(remoteConnHash, key,
2565  HASH_ENTER, &found);
2566 
2567  if (found)
2568  {
2569  libpqsrv_disconnect(rconn->conn);
2570  pfree(rconn);
2571 
2572  ereport(ERROR,
2573  (errcode(ERRCODE_DUPLICATE_OBJECT),
2574  errmsg("duplicate connection name")));
2575  }
2576 
2577  hentry->rconn = rconn;
2578 }
2579 
2580 static void
2581 deleteConnection(const char *name)
2582 {
2583  remoteConnHashEnt *hentry;
2584  bool found;
2585  char *key;
2586 
2587  if (!remoteConnHash)
2588  remoteConnHash = createConnHash();
2589 
2590  key = pstrdup(name);
2591  truncate_identifier(key, strlen(key), false);
2592  hentry = (remoteConnHashEnt *) hash_search(remoteConnHash,
2593  key, HASH_REMOVE, &found);
2594 
2595  if (!hentry)
2596  ereport(ERROR,
2597  (errcode(ERRCODE_UNDEFINED_OBJECT),
2598  errmsg("undefined connection name")));
2599 }
2600 
2601 /*
2602  * We need to make sure that the connection made used credentials
2603  * which were provided by the user, so check what credentials were
2604  * used to connect and then make sure that they came from the user.
2605  */
2606 static void
2607 dblink_security_check(PGconn *conn, remoteConn *rconn, const char *connstr)
2608 {
2609  /* Superuser bypasses security check */
2610  if (superuser())
2611  return;
2612 
2613  /* If password was used to connect, make sure it was one provided */
2614  if (PQconnectionUsedPassword(conn) && dblink_connstr_has_pw(connstr))
2615  return;
2616 
2617 #ifdef ENABLE_GSS
2618  /* If GSSAPI creds used to connect, make sure it was one delegated */
2619  if (PQconnectionUsedGSSAPI(conn) && be_gssapi_get_delegation(MyProcPort))
2620  return;
2621 #endif
2622 
2623  /* Otherwise, fail out */
2624  libpqsrv_disconnect(conn);
2625  if (rconn)
2626  pfree(rconn);
2627 
2628  ereport(ERROR,
2629  (errcode(ERRCODE_S_R_E_PROHIBITED_SQL_STATEMENT_ATTEMPTED),
2630  errmsg("password or GSSAPI delegated credentials required"),
2631  errdetail("Non-superusers may only connect using credentials they provide, eg: password in connection string or delegated GSSAPI credentials"),
2632  errhint("Ensure provided credentials match target server's authentication method.")));
2633 }
2634 
2635 /*
2636  * Function to check if the connection string includes an explicit
2637  * password, needed to ensure that non-superuser password-based auth
2638  * is using a provided password and not one picked up from the
2639  * environment.
2640  */
2641 static bool
2642 dblink_connstr_has_pw(const char *connstr)
2643 {
2644  PQconninfoOption *options;
2645  PQconninfoOption *option;
2646  bool connstr_gives_password = false;
2647 
2648  options = PQconninfoParse(connstr, NULL);
2649  if (options)
2650  {
2651  for (option = options; option->keyword != NULL; option++)
2652  {
2653  if (strcmp(option->keyword, "password") == 0)
2654  {
2655  if (option->val != NULL && option->val[0] != '\0')
2656  {
2657  connstr_gives_password = true;
2658  break;
2659  }
2660  }
2661  }
2662  PQconninfoFree(options);
2663  }
2664 
2665  return connstr_gives_password;
2666 }
2667 
2668 /*
2669  * For non-superusers, insist that the connstr specify a password, except
2670  * if GSSAPI credentials have been delegated (and we check that they are used
2671  * for the connection in dblink_security_check later). This prevents a
2672  * password or GSSAPI credentials from being picked up from .pgpass, a
2673  * service file, the environment, etc. We don't want the postgres user's
2674  * passwords or Kerberos credentials to be accessible to non-superusers.
2675  */
2676 static void
2677 dblink_connstr_check(const char *connstr)
2678 {
2679  if (superuser())
2680  return;
2681 
2682  if (dblink_connstr_has_pw(connstr))
2683  return;
2684 
2685 #ifdef ENABLE_GSS
2686  if (be_gssapi_get_delegation(MyProcPort))
2687  return;
2688 #endif
2689 
2690  ereport(ERROR,
2691  (errcode(ERRCODE_S_R_E_PROHIBITED_SQL_STATEMENT_ATTEMPTED),
2692  errmsg("password or GSSAPI delegated credentials required"),
2693  errdetail("Non-superusers must provide a password in the connection string or send delegated GSSAPI credentials.")));
2694 }
2695 
2696 /*
2697  * Report an error received from the remote server
2698  *
2699  * res: the received error result (will be freed)
2700  * fail: true for ERROR ereport, false for NOTICE
2701  * fmt and following args: sprintf-style format and values for errcontext;
2702  * the resulting string should be worded like "while <some action>"
2703  */
2704 static void
2705 dblink_res_error(PGconn *conn, const char *conname, PGresult *res,
2706  bool fail, const char *fmt,...)
2707 {
2708  int level;
2709  char *pg_diag_sqlstate = PQresultErrorField(res, PG_DIAG_SQLSTATE);
2710  char *pg_diag_message_primary = PQresultErrorField(res, PG_DIAG_MESSAGE_PRIMARY);
2711  char *pg_diag_message_detail = PQresultErrorField(res, PG_DIAG_MESSAGE_DETAIL);
2712  char *pg_diag_message_hint = PQresultErrorField(res, PG_DIAG_MESSAGE_HINT);
2713  char *pg_diag_context = PQresultErrorField(res, PG_DIAG_CONTEXT);
2714  int sqlstate;
2715  char *message_primary;
2716  char *message_detail;
2717  char *message_hint;
2718  char *message_context;
2719  va_list ap;
2720  char dblink_context_msg[512];
2721 
2722  if (fail)
2723  level = ERROR;
2724  else
2725  level = NOTICE;
2726 
2727  if (pg_diag_sqlstate)
2728  sqlstate = MAKE_SQLSTATE(pg_diag_sqlstate[0],
2729  pg_diag_sqlstate[1],
2730  pg_diag_sqlstate[2],
2731  pg_diag_sqlstate[3],
2732  pg_diag_sqlstate[4]);
2733  else
2734  sqlstate = ERRCODE_CONNECTION_FAILURE;
2735 
2736  message_primary = xpstrdup(pg_diag_message_primary);
2737  message_detail = xpstrdup(pg_diag_message_detail);
2738  message_hint = xpstrdup(pg_diag_message_hint);
2739  message_context = xpstrdup(pg_diag_context);
2740 
2741  /*
2742  * If we don't get a message from the PGresult, try the PGconn. This is
2743  * needed because for connection-level failures, PQgetResult may just
2744  * return NULL, not a PGresult at all.
2745  */
2746  if (message_primary == NULL)
2747  message_primary = pchomp(PQerrorMessage(conn));
2748 
2749  /*
2750  * Now that we've copied all the data we need out of the PGresult, it's
2751  * safe to free it. We must do this to avoid PGresult leakage. We're
2752  * leaking all the strings too, but those are in palloc'd memory that will
2753  * get cleaned up eventually.
2754  */
2755  PQclear(res);
2756 
2757  /*
2758  * Format the basic errcontext string. Below, we'll add on something
2759  * about the connection name. That's a violation of the translatability
2760  * guidelines about constructing error messages out of parts, but since
2761  * there's no translation support for dblink, there's no need to worry
2762  * about that (yet).
2763  */
2764  va_start(ap, fmt);
2765  vsnprintf(dblink_context_msg, sizeof(dblink_context_msg), fmt, ap);
2766  va_end(ap);
2767 
2768  ereport(level,
2769  (errcode(sqlstate),
2770  (message_primary != NULL && message_primary[0] != '\0') ?
2771  errmsg_internal("%s", message_primary) :
2772  errmsg("could not obtain message string for remote error"),
2773  message_detail ? errdetail_internal("%s", message_detail) : 0,
2774  message_hint ? errhint("%s", message_hint) : 0,
2775  message_context ? (errcontext("%s", message_context)) : 0,
2776  conname ?
2777  (errcontext("%s on dblink connection named \"%s\"",
2778  dblink_context_msg, conname)) :
2779  (errcontext("%s on unnamed dblink connection",
2780  dblink_context_msg))));
2781 }
2782 
2783 /*
2784  * Obtain connection string for a foreign server
2785  */
2786 static char *
2787 get_connect_string(const char *servername)
2788 {
2789  ForeignServer *foreign_server = NULL;
2790  UserMapping *user_mapping;
2791  ListCell *cell;
2792  StringInfoData buf;
2793  ForeignDataWrapper *fdw;
2794  AclResult aclresult;
2795  char *srvname;
2796 
2797  static const PQconninfoOption *options = NULL;
2798 
2799  initStringInfo(&buf);
2800 
2801  /*
2802  * Get list of valid libpq options.
2803  *
2804  * To avoid unnecessary work, we get the list once and use it throughout
2805  * the lifetime of this backend process. We don't need to care about
2806  * memory context issues, because PQconndefaults allocates with malloc.
2807  */
2808  if (!options)
2809  {
2810  options = PQconndefaults();
2811  if (!options) /* assume reason for failure is OOM */
2812  ereport(ERROR,
2813  (errcode(ERRCODE_FDW_OUT_OF_MEMORY),
2814  errmsg("out of memory"),
2815  errdetail("Could not get libpq's default connection options.")));
2816  }
2817 
2818  /* first gather the server connstr options */
2819  srvname = pstrdup(servername);
2820  truncate_identifier(srvname, strlen(srvname), false);
2821  foreign_server = GetForeignServerByName(srvname, true);
2822 
2823  if (foreign_server)
2824  {
2825  Oid serverid = foreign_server->serverid;
2826  Oid fdwid = foreign_server->fdwid;
2827  Oid userid = GetUserId();
2828 
2829  user_mapping = GetUserMapping(userid, serverid);
2830  fdw = GetForeignDataWrapper(fdwid);
2831 
2832  /* Check permissions, user must have usage on the server. */
2833  aclresult = object_aclcheck(ForeignServerRelationId, serverid, userid, ACL_USAGE);
2834  if (aclresult != ACLCHECK_OK)
2835  aclcheck_error(aclresult, OBJECT_FOREIGN_SERVER, foreign_server->servername);
2836 
2837  foreach(cell, fdw->options)
2838  {
2839  DefElem *def = lfirst(cell);
2840 
2841  if (is_valid_dblink_option(options, def->defname, ForeignDataWrapperRelationId))
2842  appendStringInfo(&buf, "%s='%s' ", def->defname,
2843  escape_param_str(strVal(def->arg)));
2844  }
2845 
2846  foreach(cell, foreign_server->options)
2847  {
2848  DefElem *def = lfirst(cell);
2849 
2850  if (is_valid_dblink_option(options, def->defname, ForeignServerRelationId))
2851  appendStringInfo(&buf, "%s='%s' ", def->defname,
2852  escape_param_str(strVal(def->arg)));
2853  }
2854 
2855  foreach(cell, user_mapping->options)
2856  {
2857 
2858  DefElem *def = lfirst(cell);
2859 
2860  if (is_valid_dblink_option(options, def->defname, UserMappingRelationId))
2861  appendStringInfo(&buf, "%s='%s' ", def->defname,
2862  escape_param_str(strVal(def->arg)));
2863  }
2864 
2865  return buf.data;
2866  }
2867  else
2868  return NULL;
2869 }
2870 
2871 /*
2872  * Escaping libpq connect parameter strings.
2873  *
2874  * Replaces "'" with "\'" and "\" with "\\".
2875  */
2876 static char *
2877 escape_param_str(const char *str)
2878 {
2879  const char *cp;
2880  StringInfoData buf;
2881 
2882  initStringInfo(&buf);
2883 
2884  for (cp = str; *cp; cp++)
2885  {
2886  if (*cp == '\\' || *cp == '\'')
2887  appendStringInfoChar(&buf, '\\');
2888  appendStringInfoChar(&buf, *cp);
2889  }
2890 
2891  return buf.data;
2892 }
2893 
2894 /*
2895  * Validate the PK-attnums argument for dblink_build_sql_insert() and related
2896  * functions, and translate to the internal representation.
2897  *
2898  * The user supplies an int2vector of 1-based logical attnums, plus a count
2899  * argument (the need for the separate count argument is historical, but we
2900  * still check it). We check that each attnum corresponds to a valid,
2901  * non-dropped attribute of the rel. We do *not* prevent attnums from being
2902  * listed twice, though the actual use-case for such things is dubious.
2903  * Note that before Postgres 9.0, the user's attnums were interpreted as
2904  * physical not logical column numbers; this was changed for future-proofing.
2905  *
2906  * The internal representation is a palloc'd int array of 0-based physical
2907  * attnums.
2908  */
2909 static void
2910 validate_pkattnums(Relation rel,
2911  int2vector *pkattnums_arg, int32 pknumatts_arg,
2912  int **pkattnums, int *pknumatts)
2913 {
2914  TupleDesc tupdesc = rel->rd_att;
2915  int natts = tupdesc->natts;
2916  int i;
2917 
2918  /* Don't take more array elements than there are */
2919  pknumatts_arg = Min(pknumatts_arg, pkattnums_arg->dim1);
2920 
2921  /* Must have at least one pk attnum selected */
2922  if (pknumatts_arg <= 0)
2923  ereport(ERROR,
2924  (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
2925  errmsg("number of key attributes must be > 0")));
2926 
2927  /* Allocate output array */
2928  *pkattnums = palloc_array(int, pknumatts_arg);
2929  *pknumatts = pknumatts_arg;
2930 
2931  /* Validate attnums and convert to internal form */
2932  for (i = 0; i < pknumatts_arg; i++)
2933  {
2934  int pkattnum = pkattnums_arg->values[i];
2935  int lnum;
2936  int j;
2937 
2938  /* Can throw error immediately if out of range */
2939  if (pkattnum <= 0 || pkattnum > natts)
2940  ereport(ERROR,
2941  (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
2942  errmsg("invalid attribute number %d", pkattnum)));
2943 
2944  /* Identify which physical column has this logical number */
2945  lnum = 0;
2946  for (j = 0; j < natts; j++)
2947  {
2948  /* dropped columns don't count */
2949  if (TupleDescAttr(tupdesc, j)->attisdropped)
2950  continue;
2951 
2952  if (++lnum == pkattnum)
2953  break;
2954  }
2955 
2956  if (j < natts)
2957  (*pkattnums)[i] = j;
2958  else
2959  ereport(ERROR,
2960  (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
2961  errmsg("invalid attribute number %d", pkattnum)));
2962  }
2963 }
2964 
2965 /*
2966  * Check if the specified connection option is valid.
2967  *
2968  * We basically allow whatever libpq thinks is an option, with these
2969  * restrictions:
2970  * debug options: disallowed
2971  * "client_encoding": disallowed
2972  * "user": valid only in USER MAPPING options
2973  * secure options (eg password): valid only in USER MAPPING options
2974  * others: valid only in FOREIGN SERVER options
2975  *
2976  * We disallow client_encoding because it would be overridden anyway via
2977  * PQclientEncoding; allowing it to be specified would merely promote
2978  * confusion.
2979  */
2980 static bool
2981 is_valid_dblink_option(const PQconninfoOption *options, const char *option,
2982  Oid context)
2983 {
2984  const PQconninfoOption *opt;
2985 
2986  /* Look up the option in libpq result */
2987  for (opt = options; opt->keyword; opt++)
2988  {
2989  if (strcmp(opt->keyword, option) == 0)
2990  break;
2991  }
2992  if (opt->keyword == NULL)
2993  return false;
2994 
2995  /* Disallow debug options (particularly "replication") */
2996  if (strchr(opt->dispchar, 'D'))
2997  return false;
2998 
2999  /* Disallow "client_encoding" */
3000  if (strcmp(opt->keyword, "client_encoding") == 0)
3001  return false;
3002 
3003  /*
3004  * If the option is "user" or marked secure, it should be specified only
3005  * in USER MAPPING. Others should be specified only in SERVER.
3006  */
3007  if (strcmp(opt->keyword, "user") == 0 || strchr(opt->dispchar, '*'))
3008  {
3009  if (context != UserMappingRelationId)
3010  return false;
3011  }
3012  else
3013  {
3014  if (context != ForeignServerRelationId)
3015  return false;
3016  }
3017 
3018  return true;
3019 }
3020 
3021 /*
3022  * Copy the remote session's values of GUCs that affect datatype I/O
3023  * and apply them locally in a new GUC nesting level. Returns the new
3024  * nestlevel (which is needed by restoreLocalGucs to undo the settings),
3025  * or -1 if no new nestlevel was needed.
3026  *
3027  * We use the equivalent of a function SET option to allow the settings to
3028  * persist only until the caller calls restoreLocalGucs. If an error is
3029  * thrown in between, guc.c will take care of undoing the settings.
3030  */
3031 static int
3032 applyRemoteGucs(PGconn *conn)
3033 {
3034  static const char *const GUCsAffectingIO[] = {
3035  "DateStyle",
3036  "IntervalStyle"
3037  };
3038 
3039  int nestlevel = -1;
3040  int i;
3041 
3042  for (i = 0; i < lengthof(GUCsAffectingIO); i++)
3043  {
3044  const char *gucName = GUCsAffectingIO[i];
3045  const char *remoteVal = PQparameterStatus(conn, gucName);
3046  const char *localVal;
3047 
3048  /*
3049  * If the remote server is pre-8.4, it won't have IntervalStyle, but
3050  * that's okay because its output format won't be ambiguous. So just
3051  * skip the GUC if we don't get a value for it. (We might eventually
3052  * need more complicated logic with remote-version checks here.)
3053  */
3054  if (remoteVal == NULL)
3055  continue;
3056 
3057  /*
3058  * Avoid GUC-setting overhead if the remote and local GUCs already
3059  * have the same value.
3060  */
3061  localVal = GetConfigOption(gucName, false, false);
3062  Assert(localVal != NULL);
3063 
3064  if (strcmp(remoteVal, localVal) == 0)
3065  continue;
3066 
3067  /* Create new GUC nest level if we didn't already */
3068  if (nestlevel < 0)
3069  nestlevel = NewGUCNestLevel();
3070 
3071  /* Apply the option (this will throw error on failure) */
3072  (void) set_config_option(gucName, remoteVal,
3073  PGC_USERSET, PGC_S_SESSION,
3074  GUC_ACTION_SAVE, true, 0, false);
3075  }
3076 
3077  return nestlevel;
3078 }
3079 
3080 /*
3081  * Restore local GUCs after they have been overlaid with remote settings.
3082  */
3083 static void
3084 restoreLocalGucs(int nestlevel)
3085 {
3086  /* Do nothing if no new nestlevel was created */
3087  if (nestlevel > 0)
3088  AtEOXact_GUC(true, nestlevel);
3089 }
AclResult
AclResult
Definition: acl.h:182
ACLCHECK_OK
@ ACLCHECK_OK
Definition: acl.h:183
aclcheck_error
void aclcheck_error(AclResult aclerr, ObjectType objtype, const char *objectname)
Definition: aclchk.c:2703
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ARR_NDIM
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Definition: array.h:294
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Definition: arrayfuncs.c:5350
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Definition: arrayfuncs.c:5420
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Definition: guc.c:2234
GetConfigOption
const char * GetConfigOption(const char *name, bool missing_ok, bool restrict_privileged)
Definition: guc.c:4313
AtEOXact_GUC
void AtEOXact_GUC(bool isCommit, int nestLevel)
Definition: guc.c:2261
set_config_option
int set_config_option(const char *name, const char *value, GucContext context, GucSource source, GucAction action, bool changeVal, int elevel, bool is_reload)
Definition: guc.c:3341
GUC_ACTION_SAVE
@ GUC_ACTION_SAVE
Definition: guc.h:201
PGC_S_SESSION
@ PGC_S_SESSION
Definition: guc.h:122
PGC_USERSET
@ PGC_USERSET
Definition: guc.h:75
str
const char * str
Definition: hashfn_unstable.h:263
HASH_STRINGS
#define HASH_STRINGS
Definition: hsearch.h:96
HASH_FIND
@ HASH_FIND
Definition: hsearch.h:113
HASH_REMOVE
@ HASH_REMOVE
Definition: hsearch.h:115
HASH_ENTER
@ HASH_ENTER
Definition: hsearch.h:114
HASH_ELEM
#define HASH_ELEM
Definition: hsearch.h:95
HeapTupleIsValid
#define HeapTupleIsValid(tuple)
Definition: htup.h:78
htup_details.h
GETSTRUCT
#define GETSTRUCT(TUP)
Definition: htup_details.h:653
nitems
#define nitems(x)
Definition: indent.h:31
match_state
struct parser_state match_state[5]
val
long val
Definition: informix.c:689
j
int j
Definition: isn.c:74
i
int i
Definition: isn.c:73
if
if(TABLE==NULL||TABLE_index==NULL)
Definition: isn.c:77
libpqsrv_cancel
static const char * libpqsrv_cancel(PGconn *conn, TimestampTz endtime)
Definition: libpq-be-fe-helpers.h:386
libpqsrv_connect
static PGconn * libpqsrv_connect(const char *conninfo, uint32 wait_event_info)
Definition: libpq-be-fe-helpers.h:66
libpqsrv_get_result
static PGresult * libpqsrv_get_result(PGconn *conn, uint32 wait_event_info)
Definition: libpq-be-fe-helpers.h:334
libpqsrv_exec
static PGresult * libpqsrv_exec(PGconn *conn, const char *query, uint32 wait_event_info)
Definition: libpq-be-fe-helpers.h:256
libpqsrv_disconnect
static void libpqsrv_disconnect(PGconn *conn)
Definition: libpq-be-fe-helpers.h:107
CONNECTION_BAD
@ CONNECTION_BAD
Definition: libpq-fe.h:82
PGRES_COMMAND_OK
@ PGRES_COMMAND_OK
Definition: libpq-fe.h:120
PGRES_SINGLE_TUPLE
@ PGRES_SINGLE_TUPLE
Definition: libpq-fe.h:133
PGRES_TUPLES_OK
@ PGRES_TUPLES_OK
Definition: libpq-fe.h:123
PQTRANS_IDLE
@ PQTRANS_IDLE
Definition: libpq-fe.h:142
fmt
static void const char * fmt
Definition: libpq_pipeline.c:29
va_end
va_end(args)
va_start
va_start(args, fmt)
LOCKMODE
int LOCKMODE
Definition: lockdefs.h:26
AccessShareLock
#define AccessShareLock
Definition: lockdefs.h:36
get_namespace_name
char * get_namespace_name(Oid nspid)
Definition: lsyscache.c:3366
get_typlenbyvalalign
void get_typlenbyvalalign(Oid typid, int16 *typlen, bool *typbyval, char *typalign)
Definition: lsyscache.c:2271
GetDatabaseEncoding
int GetDatabaseEncoding(void)
Definition: mbutils.c:1261
GetDatabaseEncodingName
const char * GetDatabaseEncodingName(void)
Definition: mbutils.c:1267
MemoryContextReset
void MemoryContextReset(MemoryContext context)
Definition: mcxt.c:383
pchomp
char * pchomp(const char *in)
Definition: mcxt.c:1724
pstrdup
char * pstrdup(const char *in)
Definition: mcxt.c:1696
pfree
void pfree(void *pointer)
Definition: mcxt.c:1521
TopMemoryContext
MemoryContext TopMemoryContext
Definition: mcxt.c:149
CurrentMemoryContext
MemoryContext CurrentMemoryContext
Definition: mcxt.c:143
MemoryContextAlloc
void * MemoryContextAlloc(MemoryContext context, Size size)
Definition: mcxt.c:1181
MemoryContextDelete
void MemoryContextDelete(MemoryContext context)
Definition: mcxt.c:454
AllocSetContextCreate
#define AllocSetContextCreate
Definition: memutils.h:129
ALLOCSET_DEFAULT_SIZES
#define ALLOCSET_DEFAULT_SIZES
Definition: memutils.h:160
CHECK_FOR_INTERRUPTS
#define CHECK_FOR_INTERRUPTS()
Definition: miscadmin.h:122
GetUserId
Oid GetUserId(void)
Definition: miscinit.c:514
RelationIsVisible
bool RelationIsVisible(Oid relid)
Definition: namespace.c:913
makeRangeVarFromNameList
RangeVar * makeRangeVarFromNameList(const List *names)
Definition: namespace.c:3554
IsA
#define IsA(nodeptr, _type_)
Definition: nodes.h:158
get_relkind_objtype
ObjectType get_relkind_objtype(char relkind)
Definition: objectaddress.c:6126
AclMode
uint64 AclMode
Definition: parsenodes.h:74
ACL_USAGE
#define ACL_USAGE
Definition: parsenodes.h:84
OBJECT_FOREIGN_SERVER
@ OBJECT_FOREIGN_SERVER
Definition: parsenodes.h:2275
ACL_SELECT
#define ACL_SELECT
Definition: parsenodes.h:77
Form_pg_attribute
FormData_pg_attribute * Form_pg_attribute
Definition: pg_attribute.h:209
relname
NameData relname
Definition: pg_class.h:38
NAMEDATALEN
#define NAMEDATALEN
Definition: pg_config_manual.h:29
connstr
static char * connstr
Definition: pg_dumpall.c:88
pg_foreign_data_wrapper.h
pg_foreign_server.h
Form_pg_index
FormData_pg_index * Form_pg_index
Definition: pg_index.h:70
lfirst
#define lfirst(lc)
Definition: pg_list.h:172
options
static char ** options
Definition: pg_recvlogical.c:59
buf
static char * buf
Definition: pg_test_fsync.c:73
pg_type.h
typalign
char typalign
Definition: pg_type.h:176
pg_user_mapping.h
pg_wchar.h
vsnprintf
#define vsnprintf
Definition: port.h:237
PointerGetDatum
static Datum PointerGetDatum(const void *X)
Definition: postgres.h:322
Datum
uintptr_t Datum
Definition: postgres.h:64
ObjectIdGetDatum
static Datum ObjectIdGetDatum(Oid X)
Definition: postgres.h:252
Int32GetDatum
static Datum Int32GetDatum(int32 X)
Definition: postgres.h:212
Oid
unsigned int Oid
Definition: postgres_ext.h:31
PG_DIAG_MESSAGE_HINT
#define PG_DIAG_MESSAGE_HINT
Definition: postgres_ext.h:59
PG_DIAG_SQLSTATE
#define PG_DIAG_SQLSTATE
Definition: postgres_ext.h:56
PG_DIAG_MESSAGE_PRIMARY
#define PG_DIAG_MESSAGE_PRIMARY
Definition: postgres_ext.h:57
PG_DIAG_MESSAGE_DETAIL
#define PG_DIAG_MESSAGE_DETAIL
Definition: postgres_ext.h:58
PG_DIAG_CONTEXT
#define PG_DIAG_CONTEXT
Definition: postgres_ext.h:63
psprintf
char * psprintf(const char *fmt,...)
Definition: psprintf.c:46
quote_ident
Datum quote_ident(PG_FUNCTION_ARGS)
Definition: quote.c:25
quote_literal_cstr
char * quote_literal_cstr(const char *rawstr)
Definition: quote.c:103
context
tree context
Definition: radixtree.h:1835
MemoryContextSwitchTo
MemoryContextSwitchTo(old_ctx)
ctl
tree ctl
Definition: radixtree.h:1853
RelationGetRelid
#define RelationGetRelid(relation)
Definition: rel.h:505
RelationGetRelationName
#define RelationGetRelationName(relation)
Definition: rel.h:539
untransformRelOptions
List * untransformRelOptions(Datum options)
Definition: reloptions.c:1331
quote_qualified_identifier
char * quote_qualified_identifier(const char *qualifier, const char *ident)
Definition: ruleutils.c:12924
ScanKeyInit
void ScanKeyInit(ScanKey entry, AttrNumber attributeNumber, StrategyNumber strategy, RegProcedure procedure, Datum argument)
Definition: scankey.c:76
truncate_identifier
void truncate_identifier(char *ident, int len, bool warn)
Definition: scansup.c:93
SPI_processed
uint64 SPI_processed
Definition: spi.c:44
SPI_tuptable
SPITupleTable * SPI_tuptable
Definition: spi.c:45
SPI_connect
int SPI_connect(void)
Definition: spi.c:94
SPI_finish
int SPI_finish(void)
Definition: spi.c:182
SPI_exec
int SPI_exec(const char *src, long tcount)
Definition: spi.c:630
SPI_getvalue
char * SPI_getvalue(HeapTuple tuple, TupleDesc tupdesc, int fnumber)
Definition: spi.c:1220
SPI_fname
char * SPI_fname(TupleDesc tupdesc, int fnumber)
Definition: spi.c:1198
SPI_copytuple
HeapTuple SPI_copytuple(HeapTuple tuple)
Definition: spi.c:1047
SPI_OK_SELECT
#define SPI_OK_SELECT
Definition: spi.h:86
relation_close
void relation_close(Relation relation, LOCKMODE lockmode)
Definition: relation.c:205
BTEqualStrategyNumber
#define BTEqualStrategyNumber
Definition: stratnum.h:31
ERRCODE_DUPLICATE_OBJECT
#define ERRCODE_DUPLICATE_OBJECT
Definition: streamutil.c:32
conn
PGconn * conn
Definition: streamutil.c:55
appendStringInfo
void appendStringInfo(StringInfo str, const char *fmt,...)
Definition: stringinfo.c:97
appendStringInfoString
void appendStringInfoString(StringInfo str, const char *s)
Definition: stringinfo.c:182
appendStringInfoChar
void appendStringInfoChar(StringInfo str, char ch)
Definition: stringinfo.c:194
initStringInfo
void initStringInfo(StringInfo str)
Definition: stringinfo.c:59
DefElem::defname
char * defname
Definition: parsenodes.h:817
DefElem::arg
Node * arg
Definition: parsenodes.h:818
ExprContext::ecxt_per_query_memory
MemoryContext ecxt_per_query_memory
Definition: execnodes.h:265
ForeignDataWrapper::options
List * options
Definition: foreign.h:31
ForeignServer::options
List * options
Definition: foreign.h:42
ForeignServer::servername
char * servername
Definition: foreign.h:39
ForeignServer::serverid
Oid serverid
Definition: foreign.h:36
FuncCallContext::user_fctx
void * user_fctx
Definition: funcapi.h:82
FuncCallContext::max_calls
uint64 max_calls
Definition: funcapi.h:74
FuncCallContext::call_cntr
uint64 call_cntr
Definition: funcapi.h:65
FuncCallContext::attinmeta
AttInMetadata * attinmeta
Definition: funcapi.h:91
FuncCallContext::multi_call_memory_ctx
MemoryContext multi_call_memory_ctx
Definition: funcapi.h:101
FunctionCallInfoBaseData::resultinfo
fmNodePtr resultinfo
Definition: fmgr.h:89
FunctionCallInfoBaseData::flinfo
FmgrInfo * flinfo
Definition: fmgr.h:87
HASH_SEQ_STATUS
Definition: hsearch.h:121
HTAB
Definition: dynahash.c:220
List
Definition: pg_list.h:54
RelationData::rd_att
TupleDesc rd_att
Definition: rel.h:112
RelationData::rd_rel
Form_pg_class rd_rel
Definition: rel.h:111
ReturnSetInfo::returnMode
SetFunctionReturnMode returnMode
Definition: execnodes.h:339
ReturnSetInfo::econtext
ExprContext * econtext
Definition: execnodes.h:335
ReturnSetInfo::setDesc
TupleDesc setDesc
Definition: execnodes.h:343
ReturnSetInfo::setResult
Tuplestorestate * setResult
Definition: execnodes.h:342
ReturnSetInfo::allowedModes
int allowedModes
Definition: execnodes.h:337
SPITupleTable::vals
HeapTuple * vals
Definition: spi.h:26
UserMapping::options
List * options
Definition: foreign.h:50
_PQconninfoOption
Definition: libpq-fe.h:260
_PQconninfoOption::keyword
char * keyword
Definition: libpq-fe.h:261
_PQconninfoOption::dispchar
char * dispchar
Definition: libpq-fe.h:266
index
Definition: type.h:95
int2vector
Definition: c.h:706
int2vector::dim1
int dim1
Definition: c.h:711
int2vector::values
int16 values[FLEXIBLE_ARRAY_MEMBER]
Definition: c.h:713
option::val
int val
Definition: getopt_long.h:21
pgNotify::be_pid
int be_pid
Definition: libpq-fe.h:219
pgNotify::relname
char * relname
Definition: libpq-fe.h:218
pgNotify::extra
char * extra
Definition: libpq-fe.h:220
pg_conn
Definition: libpq-int.h:377
pg_result
Definition: libpq-int.h:171
remoteConnHashEnt::name
char name[NAMEDATALEN]
Definition: dblink.c:148
remoteConnHashEnt::rconn
remoteConn * rconn
Definition: dblink.c:149
remoteConn::newXactForCursor
bool newXactForCursor
Definition: dblink.c:72
remoteConn::openCursorCount
int openCursorCount
Definition: dblink.c:71
remoteConn::conn
PGconn * conn
Definition: dblink.c:70
storeInfo::cstrs
char ** cstrs
Definition: dblink.c:81
storeInfo::tmpcontext
MemoryContext tmpcontext
Definition: dblink.c:80
storeInfo::cur_res
PGresult * cur_res
Definition: dblink.c:84
storeInfo::tuplestore
Tuplestorestate * tuplestore
Definition: dblink.c:78
storeInfo::fcinfo
FunctionCallInfo fcinfo
Definition: dblink.c:77
storeInfo::last_res
PGresult * last_res
Definition: dblink.c:83
storeInfo::attinmeta
AttInMetadata * attinmeta
Definition: dblink.c:79
varlena
Definition: c.h:678
superuser
bool superuser(void)
Definition: superuser.c:46
table_close
void table_close(Relation relation, LOCKMODE lockmode)
Definition: table.c:126
table_open
Relation table_open(Oid relationId, LOCKMODE lockmode)
Definition: table.c:40
table_openrv
Relation table_openrv(const RangeVar *relation, LOCKMODE lockmode)
Definition: table.c:83
CreateTemplateTupleDesc
TupleDesc CreateTemplateTupleDesc(int natts)
Definition: tupdesc.c:67
CreateTupleDescCopy
TupleDesc CreateTupleDescCopy(TupleDesc tupdesc)
Definition: tupdesc.c:133
TupleDescInitEntry
void TupleDescInitEntry(TupleDesc desc, AttrNumber attributeNumber, const char *attributeName, Oid oidtypeid, int32 typmod, int attdim)
Definition: tupdesc.c:651
TupleDescAttr
#define TupleDescAttr(tupdesc, i)
Definition: tupdesc.h:92
tuplestore_begin_heap
Tuplestorestate * tuplestore_begin_heap(bool randomAccess, bool interXact, int maxKBytes)
Definition: tuplestore.c:330
tuplestore_putvalues
void tuplestore_putvalues(Tuplestorestate *state, TupleDesc tdesc, const Datum *values, const bool *isnull)
Definition: tuplestore.c:784
tuplestore_end
void tuplestore_end(Tuplestorestate *state)
Definition: tuplestore.c:492
tuplestore_puttuple
void tuplestore_puttuple(Tuplestorestate *state, HeapTuple tuple)
Definition: tuplestore.c:764
att_align_nominal
#define att_align_nominal(cur_offset, attalign)
Definition: tupmacs.h:129
att_addlength_pointer
#define att_addlength_pointer(cur_offset, attlen, attptr)
Definition: tupmacs.h:157
TimestampTzPlusMilliseconds
#define TimestampTzPlusMilliseconds(tz, ms)
Definition: timestamp.h:85
strVal
#define strVal(v)
Definition: value.h:82
textToQualifiedNameList
List * textToQualifiedNameList(text *textval)
Definition: varlena.c:3374
getClosestMatch
const char * getClosestMatch(ClosestMatchState *state)
Definition: varlena.c:6256
text_to_cstring
char * text_to_cstring(const text *t)
Definition: varlena.c:217
cstring_to_text
text * cstring_to_text(const char *s)
Definition: varlena.c:184
initClosestMatch
void initClosestMatch(ClosestMatchState *state, const char *source, int max_d)
Definition: varlena.c:6201
updateClosestMatch
void updateClosestMatch(ClosestMatchState *state, const char *candidate)
Definition: varlena.c:6221
WaitEventExtensionNew
uint32 WaitEventExtensionNew(const char *wait_event_name)
Definition: wait_event.c:164
wait_event.h
name
const char * name
Definition: wait_event_funcs.c:28