Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * streamutil.c - utility functions for pg_basebackup, pg_receivewal and
4 : * pg_recvlogical
5 : *
6 : * Author: Magnus Hagander <magnus@hagander.net>
7 : *
8 : * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
9 : *
10 : * IDENTIFICATION
11 : * src/bin/pg_basebackup/streamutil.c
12 : *-------------------------------------------------------------------------
13 : */
14 :
15 : #include "postgres_fe.h"
16 :
17 : #include <sys/time.h>
18 : #include <unistd.h>
19 :
20 : #include "access/xlog_internal.h"
21 : #include "common/connect.h"
22 : #include "common/fe_memutils.h"
23 : #include "common/file_perm.h"
24 : #include "common/logging.h"
25 : #include "common/string.h"
26 : #include "datatype/timestamp.h"
27 : #include "port/pg_bswap.h"
28 : #include "pqexpbuffer.h"
29 : #include "receivelog.h"
30 : #include "streamutil.h"
31 :
32 : #define ERRCODE_DUPLICATE_OBJECT "42710"
33 :
34 : int WalSegSz;
35 :
36 : static bool RetrieveDataDirCreatePerm(PGconn *conn);
37 :
38 : /* SHOW command for replication connection was introduced in version 10 */
39 : #define MINIMUM_VERSION_FOR_SHOW_CMD 100000
40 :
41 : /*
42 : * Group access is supported from version 11.
43 : */
44 : #define MINIMUM_VERSION_FOR_GROUP_ACCESS 110000
45 :
46 : const char *progname;
47 : char *connection_string = NULL;
48 : char *dbhost = NULL;
49 : char *dbuser = NULL;
50 : char *dbport = NULL;
51 : char *dbname = NULL;
52 : int dbgetpassword = 0; /* 0=auto, -1=never, 1=always */
53 : static char *password = NULL;
54 : PGconn *conn = NULL;
55 :
56 : /*
57 : * Connect to the server. Returns a valid PGconn pointer if connected,
58 : * or NULL on non-permanent error. On permanent error, the function will
59 : * call exit(1) directly.
60 : */
61 : PGconn *
62 582 : GetConnection(void)
63 : {
64 : PGconn *tmpconn;
65 582 : int argcount = 7; /* dbname, replication, fallback_app_name,
66 : * host, user, port, password */
67 : int i;
68 : const char **keywords;
69 : const char **values;
70 : const char *tmpparam;
71 : bool need_password;
72 582 : PQconninfoOption *conn_opts = NULL;
73 : PQconninfoOption *conn_opt;
74 582 : char *err_msg = NULL;
75 :
76 : /* pg_recvlogical uses dbname only; others use connection_string only. */
77 : Assert(dbname == NULL || connection_string == NULL);
78 :
79 : /*
80 : * Merge the connection info inputs given in form of connection string,
81 : * options and default values (dbname=replication, replication=true, etc.)
82 : */
83 582 : i = 0;
84 582 : if (connection_string)
85 : {
86 4 : conn_opts = PQconninfoParse(connection_string, &err_msg);
87 4 : if (conn_opts == NULL)
88 0 : pg_fatal("%s", err_msg);
89 :
90 164 : for (conn_opt = conn_opts; conn_opt->keyword != NULL; conn_opt++)
91 : {
92 160 : if (conn_opt->val != NULL && conn_opt->val[0] != '\0')
93 12 : argcount++;
94 : }
95 :
96 4 : keywords = pg_malloc0((argcount + 1) * sizeof(*keywords));
97 4 : values = pg_malloc0((argcount + 1) * sizeof(*values));
98 :
99 : /*
100 : * Set dbname here already, so it can be overridden by a dbname in the
101 : * connection string.
102 : */
103 4 : keywords[i] = "dbname";
104 4 : values[i] = "replication";
105 4 : i++;
106 :
107 164 : for (conn_opt = conn_opts; conn_opt->keyword != NULL; conn_opt++)
108 : {
109 160 : if (conn_opt->val != NULL && conn_opt->val[0] != '\0')
110 : {
111 12 : keywords[i] = conn_opt->keyword;
112 12 : values[i] = conn_opt->val;
113 12 : i++;
114 : }
115 : }
116 : }
117 : else
118 : {
119 578 : keywords = pg_malloc0((argcount + 1) * sizeof(*keywords));
120 578 : values = pg_malloc0((argcount + 1) * sizeof(*values));
121 578 : keywords[i] = "dbname";
122 578 : values[i] = dbname;
123 578 : i++;
124 : }
125 :
126 582 : keywords[i] = "replication";
127 582 : values[i] = dbname == NULL ? "true" : "database";
128 582 : i++;
129 582 : keywords[i] = "fallback_application_name";
130 582 : values[i] = progname;
131 582 : i++;
132 :
133 582 : if (dbhost)
134 : {
135 214 : keywords[i] = "host";
136 214 : values[i] = dbhost;
137 214 : i++;
138 : }
139 582 : if (dbuser)
140 : {
141 14 : keywords[i] = "user";
142 14 : values[i] = dbuser;
143 14 : i++;
144 : }
145 582 : if (dbport)
146 : {
147 214 : keywords[i] = "port";
148 214 : values[i] = dbport;
149 214 : i++;
150 : }
151 :
152 : /* If -W was given, force prompt for password, but only the first time */
153 582 : need_password = (dbgetpassword == 1 && !password);
154 :
155 : do
156 : {
157 : /* Get a new password if appropriate */
158 582 : if (need_password)
159 : {
160 0 : free(password);
161 0 : password = simple_prompt("Password: ", false);
162 0 : need_password = false;
163 : }
164 :
165 : /* Use (or reuse, on a subsequent connection) password if we have it */
166 582 : if (password)
167 : {
168 0 : keywords[i] = "password";
169 0 : values[i] = password;
170 : }
171 : else
172 : {
173 582 : keywords[i] = NULL;
174 582 : values[i] = NULL;
175 : }
176 :
177 : /*
178 : * Only expand dbname when we did not already parse the argument as a
179 : * connection string ourselves.
180 : */
181 582 : tmpconn = PQconnectdbParams(keywords, values, !connection_string);
182 :
183 : /*
184 : * If there is too little memory even to allocate the PGconn object
185 : * and PQconnectdbParams returns NULL, we call exit(1) directly.
186 : */
187 582 : if (!tmpconn)
188 0 : pg_fatal("could not connect to server");
189 :
190 : /* If we need a password and -w wasn't given, loop back and get one */
191 586 : if (PQstatus(tmpconn) == CONNECTION_BAD &&
192 4 : PQconnectionNeedsPassword(tmpconn) &&
193 0 : dbgetpassword != -1)
194 : {
195 0 : PQfinish(tmpconn);
196 0 : need_password = true;
197 : }
198 : }
199 582 : while (need_password);
200 :
201 582 : if (PQstatus(tmpconn) != CONNECTION_OK)
202 : {
203 4 : pg_log_error("%s", PQerrorMessage(tmpconn));
204 4 : PQfinish(tmpconn);
205 4 : free(values);
206 4 : free(keywords);
207 4 : PQconninfoFree(conn_opts);
208 4 : return NULL;
209 : }
210 :
211 : /* Connection ok! */
212 578 : free(values);
213 578 : free(keywords);
214 578 : PQconninfoFree(conn_opts);
215 :
216 : /*
217 : * Set always-secure search path, so malicious users can't get control.
218 : * The capacity to run normal SQL queries was added in PostgreSQL 10, so
219 : * the search path cannot be changed (by us or attackers) on earlier
220 : * versions.
221 : */
222 578 : if (dbname != NULL && PQserverVersion(tmpconn) >= 100000)
223 : {
224 : PGresult *res;
225 :
226 94 : res = PQexec(tmpconn, ALWAYS_SECURE_SEARCH_PATH_SQL);
227 94 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
228 : {
229 0 : pg_log_error("could not clear search_path: %s",
230 : PQerrorMessage(tmpconn));
231 0 : PQclear(res);
232 0 : PQfinish(tmpconn);
233 0 : exit(1);
234 : }
235 94 : PQclear(res);
236 : }
237 :
238 : /*
239 : * Ensure we have the same value of integer_datetimes (now always "on") as
240 : * the server we are connecting to.
241 : */
242 578 : tmpparam = PQparameterStatus(tmpconn, "integer_datetimes");
243 578 : if (!tmpparam)
244 : {
245 0 : pg_log_error("could not determine server setting for integer_datetimes");
246 0 : PQfinish(tmpconn);
247 0 : exit(1);
248 : }
249 :
250 578 : if (strcmp(tmpparam, "on") != 0)
251 : {
252 0 : pg_log_error("integer_datetimes compile flag does not match server");
253 0 : PQfinish(tmpconn);
254 0 : exit(1);
255 : }
256 :
257 : /*
258 : * Retrieve the source data directory mode and use it to construct a umask
259 : * for creating directories and files.
260 : */
261 578 : if (!RetrieveDataDirCreatePerm(tmpconn))
262 : {
263 0 : PQfinish(tmpconn);
264 0 : exit(1);
265 : }
266 :
267 578 : return tmpconn;
268 : }
269 :
270 : /*
271 : * From version 10, explicitly set wal segment size using SHOW wal_segment_size
272 : * since ControlFile is not accessible here.
273 : */
274 : bool
275 282 : RetrieveWalSegSize(PGconn *conn)
276 : {
277 : PGresult *res;
278 : char xlog_unit[3];
279 : int xlog_val,
280 282 : multiplier = 1;
281 :
282 : /* check connection existence */
283 : Assert(conn != NULL);
284 :
285 : /* for previous versions set the default xlog seg size */
286 282 : if (PQserverVersion(conn) < MINIMUM_VERSION_FOR_SHOW_CMD)
287 : {
288 0 : WalSegSz = DEFAULT_XLOG_SEG_SIZE;
289 0 : return true;
290 : }
291 :
292 282 : res = PQexec(conn, "SHOW wal_segment_size");
293 282 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
294 : {
295 0 : pg_log_error("could not send replication command \"%s\": %s",
296 : "SHOW wal_segment_size", PQerrorMessage(conn));
297 :
298 0 : PQclear(res);
299 0 : return false;
300 : }
301 282 : if (PQntuples(res) != 1 || PQnfields(res) < 1)
302 : {
303 0 : pg_log_error("could not fetch WAL segment size: got %d rows and %d fields, expected %d rows and %d or more fields",
304 : PQntuples(res), PQnfields(res), 1, 1);
305 :
306 0 : PQclear(res);
307 0 : return false;
308 : }
309 :
310 : /* fetch xlog value and unit from the result */
311 282 : if (sscanf(PQgetvalue(res, 0, 0), "%d%2s", &xlog_val, xlog_unit) != 2)
312 : {
313 0 : pg_log_error("WAL segment size could not be parsed");
314 0 : PQclear(res);
315 0 : return false;
316 : }
317 :
318 282 : PQclear(res);
319 :
320 : /* set the multiplier based on unit to convert xlog_val to bytes */
321 282 : if (strcmp(xlog_unit, "MB") == 0)
322 282 : multiplier = 1024 * 1024;
323 0 : else if (strcmp(xlog_unit, "GB") == 0)
324 0 : multiplier = 1024 * 1024 * 1024;
325 :
326 : /* convert and set WalSegSz */
327 282 : WalSegSz = xlog_val * multiplier;
328 :
329 282 : if (!IsValidWalSegSize(WalSegSz))
330 : {
331 0 : pg_log_error(ngettext("remote server reported invalid WAL segment size (%d byte)",
332 : "remote server reported invalid WAL segment size (%d bytes)",
333 : WalSegSz),
334 : WalSegSz);
335 0 : pg_log_error_detail("The WAL segment size must be a power of two between 1 MB and 1 GB.");
336 0 : return false;
337 : }
338 :
339 282 : return true;
340 : }
341 :
342 : /*
343 : * RetrieveDataDirCreatePerm
344 : *
345 : * This function is used to determine the privileges on the server's PG data
346 : * directory and, based on that, set what the permissions will be for
347 : * directories and files we create.
348 : *
349 : * PG11 added support for (optionally) group read/execute rights to be set on
350 : * the data directory. Prior to PG11, only the owner was allowed to have rights
351 : * on the data directory.
352 : */
353 : static bool
354 578 : RetrieveDataDirCreatePerm(PGconn *conn)
355 : {
356 : PGresult *res;
357 : int data_directory_mode;
358 :
359 : /* check connection existence */
360 : Assert(conn != NULL);
361 :
362 : /* for previous versions leave the default group access */
363 578 : if (PQserverVersion(conn) < MINIMUM_VERSION_FOR_GROUP_ACCESS)
364 0 : return true;
365 :
366 578 : res = PQexec(conn, "SHOW data_directory_mode");
367 578 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
368 : {
369 0 : pg_log_error("could not send replication command \"%s\": %s",
370 : "SHOW data_directory_mode", PQerrorMessage(conn));
371 :
372 0 : PQclear(res);
373 0 : return false;
374 : }
375 578 : if (PQntuples(res) != 1 || PQnfields(res) < 1)
376 : {
377 0 : pg_log_error("could not fetch group access flag: got %d rows and %d fields, expected %d rows and %d or more fields",
378 : PQntuples(res), PQnfields(res), 1, 1);
379 :
380 0 : PQclear(res);
381 0 : return false;
382 : }
383 :
384 578 : if (sscanf(PQgetvalue(res, 0, 0), "%o", &data_directory_mode) != 1)
385 : {
386 0 : pg_log_error("group access flag could not be parsed: %s",
387 : PQgetvalue(res, 0, 0));
388 :
389 0 : PQclear(res);
390 0 : return false;
391 : }
392 :
393 578 : SetDataDirectoryCreatePerm(data_directory_mode);
394 :
395 578 : PQclear(res);
396 578 : return true;
397 : }
398 :
399 : /*
400 : * Run IDENTIFY_SYSTEM through a given connection and give back to caller
401 : * some result information if requested:
402 : * - System identifier
403 : * - Current timeline ID
404 : * - Start LSN position
405 : * - Database name (NULL in servers prior to 9.4)
406 : */
407 : bool
408 594 : RunIdentifySystem(PGconn *conn, char **sysid, TimeLineID *starttli,
409 : XLogRecPtr *startpos, char **db_name)
410 : {
411 : PGresult *res;
412 : uint32 hi,
413 : lo;
414 :
415 : /* Check connection existence */
416 : Assert(conn != NULL);
417 :
418 594 : res = PQexec(conn, "IDENTIFY_SYSTEM");
419 594 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
420 : {
421 0 : pg_log_error("could not send replication command \"%s\": %s",
422 : "IDENTIFY_SYSTEM", PQerrorMessage(conn));
423 :
424 0 : PQclear(res);
425 0 : return false;
426 : }
427 594 : if (PQntuples(res) != 1 || PQnfields(res) < 3)
428 : {
429 0 : pg_log_error("could not identify system: got %d rows and %d fields, expected %d rows and %d or more fields",
430 : PQntuples(res), PQnfields(res), 1, 3);
431 :
432 0 : PQclear(res);
433 0 : return false;
434 : }
435 :
436 : /* Get system identifier */
437 594 : if (sysid != NULL)
438 482 : *sysid = pg_strdup(PQgetvalue(res, 0, 0));
439 :
440 : /* Get timeline ID to start streaming from */
441 594 : if (starttli != NULL)
442 482 : *starttli = atoi(PQgetvalue(res, 0, 1));
443 :
444 : /* Get LSN start position if necessary */
445 594 : if (startpos != NULL)
446 : {
447 14 : if (sscanf(PQgetvalue(res, 0, 2), "%X/%X", &hi, &lo) != 2)
448 : {
449 0 : pg_log_error("could not parse write-ahead log location \"%s\"",
450 : PQgetvalue(res, 0, 2));
451 :
452 0 : PQclear(res);
453 0 : return false;
454 : }
455 14 : *startpos = ((uint64) hi) << 32 | lo;
456 : }
457 :
458 : /* Get database name, only available in 9.4 and newer versions */
459 594 : if (db_name != NULL)
460 : {
461 112 : *db_name = NULL;
462 112 : if (PQserverVersion(conn) >= 90400)
463 : {
464 112 : if (PQnfields(res) < 4)
465 : {
466 0 : pg_log_error("could not identify system: got %d rows and %d fields, expected %d rows and %d or more fields",
467 : PQntuples(res), PQnfields(res), 1, 4);
468 :
469 0 : PQclear(res);
470 0 : return false;
471 : }
472 112 : if (!PQgetisnull(res, 0, 3))
473 94 : *db_name = pg_strdup(PQgetvalue(res, 0, 3));
474 : }
475 : }
476 :
477 594 : PQclear(res);
478 594 : return true;
479 : }
480 :
481 : /*
482 : * Run READ_REPLICATION_SLOT through a given connection and give back to
483 : * caller some result information if requested for this slot:
484 : * - Start LSN position, InvalidXLogRecPtr if unknown.
485 : * - Current timeline ID, 0 if unknown.
486 : * Returns false on failure, and true otherwise.
487 : */
488 : bool
489 6 : GetSlotInformation(PGconn *conn, const char *slot_name,
490 : XLogRecPtr *restart_lsn, TimeLineID *restart_tli)
491 : {
492 : PGresult *res;
493 : PQExpBuffer query;
494 6 : XLogRecPtr lsn_loc = InvalidXLogRecPtr;
495 6 : TimeLineID tli_loc = 0;
496 :
497 6 : if (restart_lsn)
498 6 : *restart_lsn = lsn_loc;
499 6 : if (restart_tli)
500 6 : *restart_tli = tli_loc;
501 :
502 6 : query = createPQExpBuffer();
503 6 : appendPQExpBuffer(query, "READ_REPLICATION_SLOT %s", slot_name);
504 6 : res = PQexec(conn, query->data);
505 6 : destroyPQExpBuffer(query);
506 :
507 6 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
508 : {
509 0 : pg_log_error("could not send replication command \"%s\": %s",
510 : "READ_REPLICATION_SLOT", PQerrorMessage(conn));
511 0 : PQclear(res);
512 0 : return false;
513 : }
514 :
515 : /* The command should always return precisely one tuple and three fields */
516 6 : if (PQntuples(res) != 1 || PQnfields(res) != 3)
517 : {
518 0 : pg_log_error("could not read replication slot \"%s\": got %d rows and %d fields, expected %d rows and %d fields",
519 : slot_name, PQntuples(res), PQnfields(res), 1, 3);
520 0 : PQclear(res);
521 0 : return false;
522 : }
523 :
524 : /*
525 : * When the slot doesn't exist, the command returns a tuple with NULL
526 : * values. This checks only the slot type field.
527 : */
528 6 : if (PQgetisnull(res, 0, 0))
529 : {
530 2 : pg_log_error("replication slot \"%s\" does not exist", slot_name);
531 2 : PQclear(res);
532 2 : return false;
533 : }
534 :
535 : /*
536 : * Note that this cannot happen as READ_REPLICATION_SLOT supports only
537 : * physical slots, but play it safe.
538 : */
539 4 : if (strcmp(PQgetvalue(res, 0, 0), "physical") != 0)
540 : {
541 0 : pg_log_error("expected a physical replication slot, got type \"%s\" instead",
542 : PQgetvalue(res, 0, 0));
543 0 : PQclear(res);
544 0 : return false;
545 : }
546 :
547 : /* restart LSN */
548 4 : if (!PQgetisnull(res, 0, 1))
549 : {
550 : uint32 hi,
551 : lo;
552 :
553 4 : if (sscanf(PQgetvalue(res, 0, 1), "%X/%X", &hi, &lo) != 2)
554 : {
555 0 : pg_log_error("could not parse restart_lsn \"%s\" for replication slot \"%s\"",
556 : PQgetvalue(res, 0, 1), slot_name);
557 0 : PQclear(res);
558 0 : return false;
559 : }
560 4 : lsn_loc = ((uint64) hi) << 32 | lo;
561 : }
562 :
563 : /* current TLI */
564 4 : if (!PQgetisnull(res, 0, 2))
565 4 : tli_loc = (TimeLineID) atol(PQgetvalue(res, 0, 2));
566 :
567 4 : PQclear(res);
568 :
569 : /* Assign results if requested */
570 4 : if (restart_lsn)
571 4 : *restart_lsn = lsn_loc;
572 4 : if (restart_tli)
573 4 : *restart_tli = tli_loc;
574 :
575 4 : return true;
576 : }
577 :
578 : /*
579 : * Create a replication slot for the given connection. This function
580 : * returns true in case of success.
581 : */
582 : bool
583 236 : CreateReplicationSlot(PGconn *conn, const char *slot_name, const char *plugin,
584 : bool is_temporary, bool is_physical, bool reserve_wal,
585 : bool slot_exists_ok, bool two_phase)
586 : {
587 : PQExpBuffer query;
588 : PGresult *res;
589 236 : bool use_new_option_syntax = (PQserverVersion(conn) >= 150000);
590 :
591 236 : query = createPQExpBuffer();
592 :
593 : Assert((is_physical && plugin == NULL) ||
594 : (!is_physical && plugin != NULL));
595 : Assert(!(two_phase && is_physical));
596 : Assert(slot_name != NULL);
597 :
598 : /* Build base portion of query */
599 236 : appendPQExpBuffer(query, "CREATE_REPLICATION_SLOT \"%s\"", slot_name);
600 236 : if (is_temporary)
601 184 : appendPQExpBufferStr(query, " TEMPORARY");
602 236 : if (is_physical)
603 190 : appendPQExpBufferStr(query, " PHYSICAL");
604 : else
605 46 : appendPQExpBuffer(query, " LOGICAL \"%s\"", plugin);
606 :
607 : /* Add any requested options */
608 236 : if (use_new_option_syntax)
609 236 : appendPQExpBufferStr(query, " (");
610 236 : if (is_physical)
611 : {
612 190 : if (reserve_wal)
613 188 : AppendPlainCommandOption(query, use_new_option_syntax,
614 : "RESERVE_WAL");
615 : }
616 : else
617 : {
618 46 : if (two_phase && PQserverVersion(conn) >= 150000)
619 2 : AppendPlainCommandOption(query, use_new_option_syntax,
620 : "TWO_PHASE");
621 :
622 46 : if (PQserverVersion(conn) >= 100000)
623 : {
624 : /* pg_recvlogical doesn't use an exported snapshot, so suppress */
625 46 : if (use_new_option_syntax)
626 46 : AppendStringCommandOption(query, use_new_option_syntax,
627 : "SNAPSHOT", "nothing");
628 : else
629 0 : AppendPlainCommandOption(query, use_new_option_syntax,
630 : "NOEXPORT_SNAPSHOT");
631 : }
632 : }
633 236 : if (use_new_option_syntax)
634 : {
635 : /* Suppress option list if it would be empty, otherwise terminate */
636 236 : if (query->data[query->len - 1] == '(')
637 : {
638 2 : query->len -= 2;
639 2 : query->data[query->len] = '\0';
640 : }
641 : else
642 234 : appendPQExpBufferChar(query, ')');
643 : }
644 :
645 : /* Now run the query */
646 236 : res = PQexec(conn, query->data);
647 236 : if (PQresultStatus(res) != PGRES_TUPLES_OK)
648 : {
649 2 : const char *sqlstate = PQresultErrorField(res, PG_DIAG_SQLSTATE);
650 :
651 2 : if (slot_exists_ok &&
652 0 : sqlstate &&
653 0 : strcmp(sqlstate, ERRCODE_DUPLICATE_OBJECT) == 0)
654 : {
655 0 : destroyPQExpBuffer(query);
656 0 : PQclear(res);
657 0 : return true;
658 : }
659 : else
660 : {
661 2 : pg_log_error("could not send replication command \"%s\": %s",
662 : query->data, PQerrorMessage(conn));
663 :
664 2 : destroyPQExpBuffer(query);
665 2 : PQclear(res);
666 2 : return false;
667 : }
668 : }
669 :
670 234 : if (PQntuples(res) != 1 || PQnfields(res) != 4)
671 : {
672 0 : pg_log_error("could not create replication slot \"%s\": got %d rows and %d fields, expected %d rows and %d fields",
673 : slot_name,
674 : PQntuples(res), PQnfields(res), 1, 4);
675 :
676 0 : destroyPQExpBuffer(query);
677 0 : PQclear(res);
678 0 : return false;
679 : }
680 :
681 234 : destroyPQExpBuffer(query);
682 234 : PQclear(res);
683 234 : return true;
684 : }
685 :
686 : /*
687 : * Drop a replication slot for the given connection. This function
688 : * returns true in case of success.
689 : */
690 : bool
691 4 : DropReplicationSlot(PGconn *conn, const char *slot_name)
692 : {
693 : PQExpBuffer query;
694 : PGresult *res;
695 :
696 : Assert(slot_name != NULL);
697 :
698 4 : query = createPQExpBuffer();
699 :
700 : /* Build query */
701 4 : appendPQExpBuffer(query, "DROP_REPLICATION_SLOT \"%s\"",
702 : slot_name);
703 4 : res = PQexec(conn, query->data);
704 4 : if (PQresultStatus(res) != PGRES_COMMAND_OK)
705 : {
706 0 : pg_log_error("could not send replication command \"%s\": %s",
707 : query->data, PQerrorMessage(conn));
708 :
709 0 : destroyPQExpBuffer(query);
710 0 : PQclear(res);
711 0 : return false;
712 : }
713 :
714 4 : if (PQntuples(res) != 0 || PQnfields(res) != 0)
715 : {
716 0 : pg_log_error("could not drop replication slot \"%s\": got %d rows and %d fields, expected %d rows and %d fields",
717 : slot_name,
718 : PQntuples(res), PQnfields(res), 0, 0);
719 :
720 0 : destroyPQExpBuffer(query);
721 0 : PQclear(res);
722 0 : return false;
723 : }
724 :
725 4 : destroyPQExpBuffer(query);
726 4 : PQclear(res);
727 4 : return true;
728 : }
729 :
730 : /*
731 : * Append a "plain" option - one with no value - to a server command that
732 : * is being constructed.
733 : *
734 : * In the old syntax, all options were parser keywords, so you could just
735 : * write things like SOME_COMMAND OPTION1 OPTION2 'opt2value' OPTION3 42. The
736 : * new syntax uses a comma-separated list surrounded by parentheses, so the
737 : * equivalent is SOME_COMMAND (OPTION1, OPTION2 'optvalue', OPTION3 42).
738 : */
739 : void
740 1982 : AppendPlainCommandOption(PQExpBuffer buf, bool use_new_option_syntax,
741 : char *option_name)
742 : {
743 1982 : if (buf->len > 0 && buf->data[buf->len - 1] != '(')
744 : {
745 1480 : if (use_new_option_syntax)
746 1480 : appendPQExpBufferStr(buf, ", ");
747 : else
748 0 : appendPQExpBufferChar(buf, ' ');
749 : }
750 :
751 1982 : appendPQExpBuffer(buf, " %s", option_name);
752 1982 : }
753 :
754 : /*
755 : * Append an option with an associated string value to a server command that
756 : * is being constructed.
757 : *
758 : * See comments for AppendPlainCommandOption, above.
759 : */
760 : void
761 1192 : AppendStringCommandOption(PQExpBuffer buf, bool use_new_option_syntax,
762 : char *option_name, char *option_value)
763 : {
764 1192 : AppendPlainCommandOption(buf, use_new_option_syntax, option_name);
765 :
766 1192 : if (option_value != NULL)
767 : {
768 1192 : size_t length = strlen(option_value);
769 1192 : char *escaped_value = palloc(1 + 2 * length);
770 :
771 1192 : PQescapeStringConn(conn, escaped_value, option_value, length, NULL);
772 1192 : appendPQExpBuffer(buf, " '%s'", escaped_value);
773 1192 : pfree(escaped_value);
774 : }
775 1192 : }
776 :
777 : /*
778 : * Append an option with an associated integer value to a server command
779 : * is being constructed.
780 : *
781 : * See comments for AppendPlainCommandOption, above.
782 : */
783 : void
784 256 : AppendIntegerCommandOption(PQExpBuffer buf, bool use_new_option_syntax,
785 : char *option_name, int32 option_value)
786 : {
787 256 : AppendPlainCommandOption(buf, use_new_option_syntax, option_name);
788 :
789 256 : appendPQExpBuffer(buf, " %d", option_value);
790 256 : }
791 :
792 : /*
793 : * Frontend version of GetCurrentTimestamp(), since we are not linked with
794 : * backend code.
795 : */
796 : TimestampTz
797 4428 : feGetCurrentTimestamp(void)
798 : {
799 : TimestampTz result;
800 : struct timeval tp;
801 :
802 4428 : gettimeofday(&tp, NULL);
803 :
804 4428 : result = (TimestampTz) tp.tv_sec -
805 : ((POSTGRES_EPOCH_JDATE - UNIX_EPOCH_JDATE) * SECS_PER_DAY);
806 4428 : result = (result * USECS_PER_SEC) + tp.tv_usec;
807 :
808 4428 : return result;
809 : }
810 :
811 : /*
812 : * Frontend version of TimestampDifference(), since we are not linked with
813 : * backend code.
814 : */
815 : void
816 3420 : feTimestampDifference(TimestampTz start_time, TimestampTz stop_time,
817 : long *secs, int *microsecs)
818 : {
819 3420 : TimestampTz diff = stop_time - start_time;
820 :
821 3420 : if (diff <= 0)
822 : {
823 0 : *secs = 0;
824 0 : *microsecs = 0;
825 : }
826 : else
827 : {
828 3420 : *secs = (long) (diff / USECS_PER_SEC);
829 3420 : *microsecs = (int) (diff % USECS_PER_SEC);
830 : }
831 3420 : }
832 :
833 : /*
834 : * Frontend version of TimestampDifferenceExceeds(), since we are not
835 : * linked with backend code.
836 : */
837 : bool
838 5800 : feTimestampDifferenceExceeds(TimestampTz start_time,
839 : TimestampTz stop_time,
840 : int msec)
841 : {
842 5800 : TimestampTz diff = stop_time - start_time;
843 :
844 5800 : return (diff >= msec * INT64CONST(1000));
845 : }
846 :
847 : /*
848 : * Converts an int64 to network byte order.
849 : */
850 : void
851 992 : fe_sendint64(int64 i, char *buf)
852 : {
853 992 : uint64 n64 = pg_hton64(i);
854 :
855 992 : memcpy(buf, &n64, sizeof(n64));
856 992 : }
857 :
858 : /*
859 : * Converts an int64 from network byte order to native format.
860 : */
861 : int64
862 6692 : fe_recvint64(char *buf)
863 : {
864 : uint64 n64;
865 :
866 6692 : memcpy(&n64, buf, sizeof(n64));
867 :
868 6692 : return pg_ntoh64(n64);
869 : }
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