TLA Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * pg_backup_db.c
4 : *
5 : * Implements the basic DB functions used by the archiver.
6 : *
7 : * IDENTIFICATION
8 : * src/bin/pg_dump/pg_backup_db.c
9 : *
10 : *-------------------------------------------------------------------------
11 : */
12 : #include "postgres_fe.h"
13 :
14 : #include <unistd.h>
15 : #include <ctype.h>
16 : #ifdef HAVE_TERMIOS_H
17 : #include <termios.h>
18 : #endif
19 :
20 : #include "common/connect.h"
21 : #include "common/string.h"
22 : #include "dumputils.h"
23 : #include "fe_utils/string_utils.h"
24 : #include "parallel.h"
25 : #include "pg_backup_archiver.h"
26 : #include "pg_backup_db.h"
27 : #include "pg_backup_utils.h"
28 :
29 : static void _check_database_version(ArchiveHandle *AH);
30 : static void notice_processor(void *arg, const char *message);
31 :
32 : static void
33 CBC 186 : _check_database_version(ArchiveHandle *AH)
34 : {
35 : const char *remoteversion_str;
36 : int remoteversion;
37 : PGresult *res;
38 :
39 186 : remoteversion_str = PQparameterStatus(AH->connection, "server_version");
40 186 : remoteversion = PQserverVersion(AH->connection);
41 186 : if (remoteversion == 0 || !remoteversion_str)
42 UBC 0 : pg_fatal("could not get server_version from libpq");
43 :
44 CBC 186 : AH->public.remoteVersionStr = pg_strdup(remoteversion_str);
45 186 : AH->public.remoteVersion = remoteversion;
46 186 : if (!AH->archiveRemoteVersion)
47 131 : AH->archiveRemoteVersion = AH->public.remoteVersionStr;
48 :
49 186 : if (remoteversion != PG_VERSION_NUM
50 UBC 0 : && (remoteversion < AH->public.minRemoteVersion ||
51 0 : remoteversion > AH->public.maxRemoteVersion))
52 : {
53 0 : pg_log_error("aborting because of server version mismatch");
54 0 : pg_log_error_detail("server version: %s; %s version: %s",
55 : remoteversion_str, progname, PG_VERSION);
56 0 : exit(1);
57 : }
58 :
59 : /*
60 : * Check if server is in recovery mode, which means we are on a hot
61 : * standby.
62 : */
63 CBC 186 : res = ExecuteSqlQueryForSingleRow((Archive *) AH,
64 : "SELECT pg_catalog.pg_is_in_recovery()");
65 186 : AH->public.isStandby = (strcmp(PQgetvalue(res, 0, 0), "t") == 0);
66 186 : PQclear(res);
67 186 : }
68 :
69 : /*
70 : * Reconnect to the server. If dbname is not NULL, use that database,
71 : * else the one associated with the archive handle.
72 : */
73 : void
74 13 : ReconnectToServer(ArchiveHandle *AH, const char *dbname)
75 : {
76 13 : PGconn *oldConn = AH->connection;
77 13 : RestoreOptions *ropt = AH->public.ropt;
78 :
79 : /*
80 : * Save the dbname, if given, in override_dbname so that it will also
81 : * affect any later reconnection attempt.
82 : */
83 13 : if (dbname)
84 13 : ropt->cparams.override_dbname = pg_strdup(dbname);
85 :
86 : /*
87 : * Note: we want to establish the new connection, and in particular update
88 : * ArchiveHandle's connCancel, before closing old connection. Otherwise
89 : * an ill-timed SIGINT could try to access a dead connection.
90 : */
91 13 : AH->connection = NULL; /* dodge error check in ConnectDatabase */
92 :
93 13 : ConnectDatabase((Archive *) AH, &ropt->cparams, true);
94 :
95 13 : PQfinish(oldConn);
96 13 : }
97 :
98 : /*
99 : * Make, or remake, a database connection with the given parameters.
100 : *
101 : * The resulting connection handle is stored in AHX->connection.
102 : *
103 : * An interactive password prompt is automatically issued if required.
104 : * We store the results of that in AHX->savedPassword.
105 : * Note: it's not really all that sensible to use a single-entry password
106 : * cache if the username keeps changing. In current usage, however, the
107 : * username never does change, so one savedPassword is sufficient.
108 : */
109 : void
110 187 : ConnectDatabase(Archive *AHX,
111 : const ConnParams *cparams,
112 : bool isReconnect)
113 : {
114 187 : ArchiveHandle *AH = (ArchiveHandle *) AHX;
115 : trivalue prompt_password;
116 : char *password;
117 : bool new_pass;
118 :
119 187 : if (AH->connection)
120 UBC 0 : pg_fatal("already connected to a database");
121 :
122 : /* Never prompt for a password during a reconnection */
123 CBC 187 : prompt_password = isReconnect ? TRI_NO : cparams->promptPassword;
124 :
125 187 : password = AH->savedPassword;
126 :
127 187 : if (prompt_password == TRI_YES && password == NULL)
128 UBC 0 : password = simple_prompt("Password: ", false);
129 :
130 : /*
131 : * Start the connection. Loop until we have a password if requested by
132 : * backend.
133 : */
134 : do
135 : {
136 : const char *keywords[8];
137 : const char *values[8];
138 CBC 187 : int i = 0;
139 :
140 : /*
141 : * If dbname is a connstring, its entries can override the other
142 : * values obtained from cparams; but in turn, override_dbname can
143 : * override the dbname component of it.
144 : */
145 187 : keywords[i] = "host";
146 187 : values[i++] = cparams->pghost;
147 187 : keywords[i] = "port";
148 187 : values[i++] = cparams->pgport;
149 187 : keywords[i] = "user";
150 187 : values[i++] = cparams->username;
151 187 : keywords[i] = "password";
152 187 : values[i++] = password;
153 187 : keywords[i] = "dbname";
154 187 : values[i++] = cparams->dbname;
155 187 : if (cparams->override_dbname)
156 : {
157 16 : keywords[i] = "dbname";
158 16 : values[i++] = cparams->override_dbname;
159 : }
160 187 : keywords[i] = "fallback_application_name";
161 187 : values[i++] = progname;
162 187 : keywords[i] = NULL;
163 187 : values[i++] = NULL;
164 187 : Assert(i <= lengthof(keywords));
165 :
166 187 : new_pass = false;
167 187 : AH->connection = PQconnectdbParams(keywords, values, true);
168 :
169 187 : if (!AH->connection)
170 UBC 0 : pg_fatal("could not connect to database");
171 :
172 CBC 188 : if (PQstatus(AH->connection) == CONNECTION_BAD &&
173 1 : PQconnectionNeedsPassword(AH->connection) &&
174 UBC 0 : password == NULL &&
175 : prompt_password != TRI_NO)
176 : {
177 0 : PQfinish(AH->connection);
178 0 : password = simple_prompt("Password: ", false);
179 0 : new_pass = true;
180 : }
181 CBC 187 : } while (new_pass);
182 :
183 : /* check to see that the backend connection was successfully made */
184 187 : if (PQstatus(AH->connection) == CONNECTION_BAD)
185 : {
186 1 : if (isReconnect)
187 UBC 0 : pg_fatal("reconnection failed: %s",
188 : PQerrorMessage(AH->connection));
189 : else
190 CBC 1 : pg_fatal("%s",
191 : PQerrorMessage(AH->connection));
192 : }
193 :
194 : /* Start strict; later phases may override this. */
195 186 : PQclear(ExecuteSqlQueryForSingleRow((Archive *) AH,
196 : ALWAYS_SECURE_SEARCH_PATH_SQL));
197 :
198 186 : if (password && password != AH->savedPassword)
199 UBC 0 : free(password);
200 :
201 : /*
202 : * We want to remember connection's actual password, whether or not we got
203 : * it by prompting. So we don't just store the password variable.
204 : */
205 CBC 186 : if (PQconnectionUsedPassword(AH->connection))
206 : {
207 UNC 0 : free(AH->savedPassword);
208 UIC 0 : AH->savedPassword = pg_strdup(PQpass(AH->connection));
209 : }
210 :
211 ECB : /* check for version mismatch */
212 GIC 186 : _check_database_version(AH);
213 ECB :
214 GIC 186 : PQsetNoticeProcessor(AH->connection, notice_processor, NULL);
215 :
216 ECB : /* arrange for SIGINT to issue a query cancel on this connection */
217 CBC 186 : set_archive_cancel_info(AH, AH->connection);
218 GIC 186 : }
219 :
220 : /*
221 : * Close the connection to the database and also cancel off the query if we
222 : * have one running.
223 : */
224 ECB : void
225 GIC 172 : DisconnectDatabase(Archive *AHX)
226 ECB : {
227 GIC 172 : ArchiveHandle *AH = (ArchiveHandle *) AHX;
228 : char errbuf[1];
229 ECB :
230 GBC 172 : if (!AH->connection)
231 UIC 0 : return;
232 ECB :
233 GIC 172 : if (AH->connCancel)
234 : {
235 : /*
236 : * If we have an active query, send a cancel before closing, ignoring
237 : * any errors. This is of no use for a normal exit, but might be
238 : * helpful during pg_fatal().
239 ECB : */
240 GBC 171 : if (PQtransactionStatus(AH->connection) == PQTRANS_ACTIVE)
241 UIC 0 : (void) PQcancel(AH->connCancel, errbuf, sizeof(errbuf));
242 :
243 : /*
244 : * Prevent signal handler from sending a cancel after this.
245 ECB : */
246 GIC 171 : set_archive_cancel_info(AH, NULL);
247 : }
248 ECB :
249 CBC 172 : PQfinish(AH->connection);
250 GIC 172 : AH->connection = NULL;
251 : }
252 :
253 ECB : PGconn *
254 GIC 3311 : GetConnection(Archive *AHX)
255 ECB : {
256 GIC 3311 : ArchiveHandle *AH = (ArchiveHandle *) AHX;
257 ECB :
258 GIC 3311 : return AH->connection;
259 : }
260 :
261 EUB : static void
262 UIC 0 : notice_processor(void *arg, const char *message)
263 EUB : {
264 UBC 0 : pg_log_info("%s", message);
265 UIC 0 : }
266 :
267 : /* Like pg_fatal(), but with a complaint about a particular query. */
268 ECB : static void
269 GIC 2 : die_on_query_failure(ArchiveHandle *AH, const char *query)
270 ECB : {
271 GIC 2 : pg_log_error("query failed: %s",
272 ECB : PQerrorMessage(AH->connection));
273 CBC 2 : pg_log_error_detail("Query was: %s", query);
274 GIC 2 : exit(1);
275 : }
276 :
277 ECB : void
278 GIC 2338 : ExecuteSqlStatement(Archive *AHX, const char *query)
279 ECB : {
280 GIC 2338 : ArchiveHandle *AH = (ArchiveHandle *) AHX;
281 : PGresult *res;
282 ECB :
283 CBC 2338 : res = PQexec(AH->connection, query);
284 2338 : if (PQresultStatus(res) != PGRES_COMMAND_OK)
285 1 : die_on_query_failure(AH, query);
286 2337 : PQclear(res);
287 GIC 2337 : }
288 :
289 ECB : PGresult *
290 GIC 19417 : ExecuteSqlQuery(Archive *AHX, const char *query, ExecStatusType status)
291 ECB : {
292 GIC 19417 : ArchiveHandle *AH = (ArchiveHandle *) AHX;
293 : PGresult *res;
294 ECB :
295 CBC 19417 : res = PQexec(AH->connection, query);
296 19417 : if (PQresultStatus(res) != status)
297 1 : die_on_query_failure(AH, query);
298 GIC 19416 : return res;
299 : }
300 :
301 : /*
302 : * Execute an SQL query and verify that we got exactly one row back.
303 : */
304 ECB : PGresult *
305 GIC 7913 : ExecuteSqlQueryForSingleRow(Archive *fout, const char *query)
306 : {
307 : PGresult *res;
308 : int ntups;
309 ECB :
310 GIC 7913 : res = ExecuteSqlQuery(fout, query, PGRES_TUPLES_OK);
311 :
312 ECB : /* Expecting a single result only */
313 CBC 7913 : ntups = PQntuples(res);
314 GBC 7913 : if (ntups != 1)
315 UIC 0 : pg_fatal(ngettext("query returned %d row instead of one: %s",
316 : "query returned %d rows instead of one: %s",
317 : ntups),
318 : ntups, query);
319 ECB :
320 GIC 7913 : return res;
321 : }
322 :
323 : /*
324 : * Convenience function to send a query.
325 : * Monitors result to detect COPY statements
326 : */
327 ECB : static void
328 GIC 6576 : ExecuteSqlCommand(ArchiveHandle *AH, const char *qry, const char *desc)
329 ECB : {
330 GIC 6576 : PGconn *conn = AH->connection;
331 : PGresult *res;
332 :
333 : #ifdef NOT_USED
334 : fprintf(stderr, "Executing: '%s'\n\n", qry);
335 ECB : #endif
336 GIC 6576 : res = PQexec(conn, qry);
337 ECB :
338 GIC 6576 : switch (PQresultStatus(res))
339 ECB : {
340 GIC 6567 : case PGRES_COMMAND_OK:
341 : case PGRES_TUPLES_OK:
342 : case PGRES_EMPTY_QUERY:
343 ECB : /* A-OK */
344 CBC 6567 : break;
345 GIC 9 : case PGRES_COPY_IN:
346 ECB : /* Assume this is an expected result */
347 CBC 9 : AH->pgCopyIn = true;
348 GBC 9 : break;
349 UIC 0 : default:
350 EUB : /* trouble */
351 UIC 0 : warn_or_exit_horribly(AH, "%s: %sCommand was: %s",
352 EUB : desc, PQerrorMessage(conn), qry);
353 UIC 0 : break;
354 : }
355 ECB :
356 CBC 6576 : PQclear(res);
357 GIC 6576 : }
358 :
359 :
360 : /*
361 : * Process non-COPY table data (that is, INSERT commands).
362 : *
363 : * The commands have been run together as one long string for compressibility,
364 : * and we are receiving them in bufferloads with arbitrary boundaries, so we
365 : * have to locate command boundaries and save partial commands across calls.
366 : * All state must be kept in AH->sqlparse, not in local variables of this
367 : * routine. We assume that AH->sqlparse was filled with zeroes when created.
368 : *
369 : * We have to lex the data to the extent of identifying literals and quoted
370 : * identifiers, so that we can recognize statement-terminating semicolons.
371 : * We assume that INSERT data will not contain SQL comments, E'' literals,
372 : * or dollar-quoted strings, so this is much simpler than a full SQL lexer.
373 : *
374 : * Note: when restoring from a pre-9.0 dump file, this code is also used to
375 : * process BLOB COMMENTS data, which has the same problem of containing
376 : * multiple SQL commands that might be split across bufferloads. Fortunately,
377 : * that data won't contain anything complicated to lex either.
378 : */
379 ECB : static void
380 GIC 37 : ExecuteSimpleCommands(ArchiveHandle *AH, const char *buf, size_t bufLen)
381 ECB : {
382 CBC 37 : const char *qry = buf;
383 GIC 37 : const char *eos = buf + bufLen;
384 :
385 ECB : /* initialize command buffer if first time through */
386 CBC 37 : if (AH->sqlparse.curCmd == NULL)
387 GIC 3 : AH->sqlparse.curCmd = createPQExpBuffer();
388 ECB :
389 GIC 129730 : for (; qry < eos; qry++)
390 ECB : {
391 GIC 129693 : char ch = *qry;
392 :
393 ECB : /* For neatness, we skip any newlines between commands */
394 CBC 129693 : if (!(ch == '\n' && AH->sqlparse.curCmd->len == 0))
395 GIC 126679 : appendPQExpBufferChar(AH->sqlparse.curCmd, ch);
396 ECB :
397 GIC 129693 : switch (AH->sqlparse.state)
398 ECB : {
399 CBC 125693 : case SQL_SCAN: /* Default state == 0, set in _allocAH */
400 GIC 125693 : if (ch == ';')
401 : {
402 : /*
403 : * We've found the end of a statement. Send it and reset
404 : * the buffer.
405 ECB : */
406 GIC 3000 : ExecuteSqlCommand(AH, AH->sqlparse.curCmd->data,
407 ECB : "could not execute query");
408 GIC 3000 : resetPQExpBuffer(AH->sqlparse.curCmd);
409 ECB : }
410 GIC 122693 : else if (ch == '\'')
411 ECB : {
412 CBC 2000 : AH->sqlparse.state = SQL_IN_SINGLE_QUOTE;
413 GIC 2000 : AH->sqlparse.backSlash = false;
414 ECB : }
415 GIC 120693 : else if (ch == '"')
416 EUB : {
417 UIC 0 : AH->sqlparse.state = SQL_IN_DOUBLE_QUOTE;
418 ECB : }
419 GIC 125693 : break;
420 ECB :
421 GIC 4000 : case SQL_IN_SINGLE_QUOTE:
422 ECB : /* We needn't handle '' specially */
423 CBC 4000 : if (ch == '\'' && !AH->sqlparse.backSlash)
424 2000 : AH->sqlparse.state = SQL_SCAN;
425 GBC 2000 : else if (ch == '\\' && !AH->public.std_strings)
426 UIC 0 : AH->sqlparse.backSlash = !AH->sqlparse.backSlash;
427 ECB : else
428 CBC 2000 : AH->sqlparse.backSlash = false;
429 GIC 4000 : break;
430 EUB :
431 UIC 0 : case SQL_IN_DOUBLE_QUOTE:
432 EUB : /* We needn't handle "" specially */
433 UBC 0 : if (ch == '"')
434 0 : AH->sqlparse.state = SQL_SCAN;
435 UIC 0 : break;
436 : }
437 ECB : }
438 GIC 37 : }
439 :
440 :
441 : /*
442 : * Implement ahwrite() for direct-to-DB restore
443 : */
444 ECB : int
445 GIC 3603 : ExecuteSqlCommandBuf(Archive *AHX, const char *buf, size_t bufLen)
446 ECB : {
447 GIC 3603 : ArchiveHandle *AH = (ArchiveHandle *) AHX;
448 ECB :
449 GIC 3603 : if (AH->outputKind == OUTPUT_COPYDATA)
450 : {
451 : /*
452 : * COPY data.
453 : *
454 : * We drop the data on the floor if libpq has failed to enter COPY
455 : * mode; this allows us to behave reasonably when trying to continue
456 : * after an error in a COPY command.
457 ECB : */
458 CBC 20 : if (AH->pgCopyIn &&
459 GBC 10 : PQputCopyData(AH->connection, buf, bufLen) <= 0)
460 UIC 0 : pg_fatal("error returned by PQputCopyData: %s",
461 : PQerrorMessage(AH->connection));
462 ECB : }
463 GIC 3593 : else if (AH->outputKind == OUTPUT_OTHERDATA)
464 : {
465 : /*
466 : * Table data expressed as INSERT commands; or, in old dump files,
467 : * BLOB COMMENTS data (which is expressed as COMMENT ON commands).
468 ECB : */
469 GIC 37 : ExecuteSimpleCommands(AH, buf, bufLen);
470 : }
471 : else
472 : {
473 : /*
474 : * General SQL commands; we assume that commands will not be split
475 : * across calls.
476 : *
477 : * In most cases the data passed to us will be a null-terminated
478 : * string, but if it's not, we have to add a trailing null.
479 ECB : */
480 CBC 3556 : if (buf[bufLen] == '\0')
481 GIC 3556 : ExecuteSqlCommand(AH, buf, "could not execute query");
482 : else
483 EUB : {
484 UIC 0 : char *str = (char *) pg_malloc(bufLen + 1);
485 EUB :
486 UBC 0 : memcpy(str, buf, bufLen);
487 0 : str[bufLen] = '\0';
488 0 : ExecuteSqlCommand(AH, str, "could not execute query");
489 UIC 0 : free(str);
490 : }
491 : }
492 ECB :
493 GIC 3603 : return bufLen;
494 : }
495 :
496 : /*
497 : * Terminate a COPY operation during direct-to-DB restore
498 : */
499 ECB : void
500 GIC 9 : EndDBCopyMode(Archive *AHX, const char *tocEntryTag)
501 ECB : {
502 GIC 9 : ArchiveHandle *AH = (ArchiveHandle *) AHX;
503 ECB :
504 GIC 9 : if (AH->pgCopyIn)
505 : {
506 : PGresult *res;
507 ECB :
508 GBC 9 : if (PQputCopyEnd(AH->connection, NULL) <= 0)
509 UIC 0 : pg_fatal("error returned by PQputCopyEnd: %s",
510 : PQerrorMessage(AH->connection));
511 :
512 ECB : /* Check command status and return to normal libpq state */
513 CBC 9 : res = PQgetResult(AH->connection);
514 GBC 9 : if (PQresultStatus(res) != PGRES_COMMAND_OK)
515 UBC 0 : warn_or_exit_horribly(AH, "COPY failed for table \"%s\": %s",
516 LBC 0 : tocEntryTag, PQerrorMessage(AH->connection));
517 GIC 9 : PQclear(res);
518 :
519 ECB : /* Do this to ensure we've pumped libpq back to idle state */
520 GBC 9 : if (PQgetResult(AH->connection) != NULL)
521 UIC 0 : pg_log_warning("unexpected extra results during COPY of table \"%s\"",
522 : tocEntryTag);
523 ECB :
524 GIC 9 : AH->pgCopyIn = false;
525 ECB : }
526 GIC 9 : }
527 :
528 ECB : void
529 GIC 10 : StartTransaction(Archive *AHX)
530 ECB : {
531 GIC 10 : ArchiveHandle *AH = (ArchiveHandle *) AHX;
532 ECB :
533 CBC 10 : ExecuteSqlCommand(AH, "BEGIN", "could not start database transaction");
534 GIC 10 : }
535 :
536 ECB : void
537 GIC 10 : CommitTransaction(Archive *AHX)
538 ECB : {
539 GIC 10 : ArchiveHandle *AH = (ArchiveHandle *) AHX;
540 ECB :
541 CBC 10 : ExecuteSqlCommand(AH, "COMMIT", "could not commit database transaction");
542 GIC 10 : }
543 :
544 ECB : void
545 GNC 2 : DropLOIfExists(ArchiveHandle *AH, Oid oid)
546 : {
547 : /*
548 : * If we are not restoring to a direct database connection, we have to
549 : * guess about how to detect whether the LO exists. Assume new-style.
550 ECB : */
551 CBC 4 : if (AH->connection == NULL ||
552 GIC 2 : PQserverVersion(AH->connection) >= 90000)
553 ECB : {
554 GIC 2 : ahprintf(AH,
555 : "SELECT pg_catalog.lo_unlink(oid) "
556 : "FROM pg_catalog.pg_largeobject_metadata "
557 : "WHERE oid = '%u';\n",
558 : oid);
559 : }
560 : else
561 : {
562 EUB : /* Restoring to pre-9.0 server, so do it the old way */
563 UIC 0 : ahprintf(AH,
564 : "SELECT CASE WHEN EXISTS("
565 : "SELECT 1 FROM pg_catalog.pg_largeobject WHERE loid = '%u'"
566 : ") THEN pg_catalog.lo_unlink('%u') END;\n",
567 : oid, oid);
568 ECB : }
569 GIC 2 : }
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