PostgreSQL Source Code git master
All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Pages
option.c
Go to the documentation of this file.
1/*-------------------------------------------------------------------------
2 *
3 * option.c
4 * FDW and GUC option handling for postgres_fdw
5 *
6 * Portions Copyright (c) 2012-2024, PostgreSQL Global Development Group
7 *
8 * IDENTIFICATION
9 * contrib/postgres_fdw/option.c
10 *
11 *-------------------------------------------------------------------------
12 */
13#include "postgres.h"
14
15#include "access/reloptions.h"
19#include "commands/defrem.h"
20#include "commands/extension.h"
21#include "libpq/libpq-be.h"
22#include "postgres_fdw.h"
23#include "utils/guc.h"
24#include "utils/varlena.h"
25
26/*
27 * Describes the valid options for objects that this wrapper uses.
28 */
29typedef struct PgFdwOption
30{
31 const char *keyword;
32 Oid optcontext; /* OID of catalog in which option may appear */
33 bool is_libpq_opt; /* true if it's used in libpq */
35
36/*
37 * Valid options for postgres_fdw.
38 * Allocated and filled in InitPgFdwOptions.
39 */
41
42/*
43 * Valid options for libpq.
44 * Allocated and filled in InitPgFdwOptions.
45 */
47
48/*
49 * GUC parameters
50 */
52
53/*
54 * Helper functions
55 */
56static void InitPgFdwOptions(void);
57static bool is_valid_option(const char *keyword, Oid context);
58static bool is_libpq_option(const char *keyword);
59
60#include "miscadmin.h"
61
62/*
63 * Validate the generic options given to a FOREIGN DATA WRAPPER, SERVER,
64 * USER MAPPING or FOREIGN TABLE that uses postgres_fdw.
65 *
66 * Raise an ERROR if the option or its value is considered invalid.
67 */
69
72{
73 List *options_list = untransformRelOptions(PG_GETARG_DATUM(0));
74 Oid catalog = PG_GETARG_OID(1);
75 ListCell *cell;
76
77 /* Build our options lists if we didn't yet. */
79
80 /*
81 * Check that only options supported by postgres_fdw, and allowed for the
82 * current object type, are given.
83 */
84 foreach(cell, options_list)
85 {
86 DefElem *def = (DefElem *) lfirst(cell);
87
88 if (!is_valid_option(def->defname, catalog))
89 {
90 /*
91 * Unknown option specified, complain about it. Provide a hint
92 * with a valid option that looks similar, if there is one.
93 */
94 PgFdwOption *opt;
95 const char *closest_match;
97 bool has_valid_options = false;
98
100 for (opt = postgres_fdw_options; opt->keyword; opt++)
101 {
102 if (catalog == opt->optcontext)
103 {
104 has_valid_options = true;
106 }
107 }
108
109 closest_match = getClosestMatch(&match_state);
111 (errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
112 errmsg("invalid option \"%s\"", def->defname),
113 has_valid_options ? closest_match ?
114 errhint("Perhaps you meant the option \"%s\".",
115 closest_match) : 0 :
116 errhint("There are no valid options in this context.")));
117 }
118
119 /*
120 * Validate option value, when we can do so without any context.
121 */
122 if (strcmp(def->defname, "use_remote_estimate") == 0 ||
123 strcmp(def->defname, "updatable") == 0 ||
124 strcmp(def->defname, "truncatable") == 0 ||
125 strcmp(def->defname, "async_capable") == 0 ||
126 strcmp(def->defname, "parallel_commit") == 0 ||
127 strcmp(def->defname, "parallel_abort") == 0 ||
128 strcmp(def->defname, "keep_connections") == 0)
129 {
130 /* these accept only boolean values */
131 (void) defGetBoolean(def);
132 }
133 else if (strcmp(def->defname, "fdw_startup_cost") == 0 ||
134 strcmp(def->defname, "fdw_tuple_cost") == 0)
135 {
136 /*
137 * These must have a floating point value greater than or equal to
138 * zero.
139 */
140 char *value;
141 double real_val;
142 bool is_parsed;
143
144 value = defGetString(def);
145 is_parsed = parse_real(value, &real_val, 0, NULL);
146
147 if (!is_parsed)
149 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
150 errmsg("invalid value for floating point option \"%s\": %s",
151 def->defname, value)));
152
153 if (real_val < 0)
155 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
156 errmsg("\"%s\" must be a floating point value greater than or equal to zero",
157 def->defname)));
158 }
159 else if (strcmp(def->defname, "extensions") == 0)
160 {
161 /* check list syntax, warn about uninstalled extensions */
162 (void) ExtractExtensionList(defGetString(def), true);
163 }
164 else if (strcmp(def->defname, "fetch_size") == 0 ||
165 strcmp(def->defname, "batch_size") == 0)
166 {
167 char *value;
168 int int_val;
169 bool is_parsed;
170
171 value = defGetString(def);
172 is_parsed = parse_int(value, &int_val, 0, NULL);
173
174 if (!is_parsed)
176 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
177 errmsg("invalid value for integer option \"%s\": %s",
178 def->defname, value)));
179
180 if (int_val <= 0)
182 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
183 errmsg("\"%s\" must be an integer value greater than zero",
184 def->defname)));
185 }
186 else if (strcmp(def->defname, "password_required") == 0)
187 {
188 bool pw_required = defGetBoolean(def);
189
190 /*
191 * Only the superuser may set this option on a user mapping, or
192 * alter a user mapping on which this option is set. We allow a
193 * user to clear this option if it's set - in fact, we don't have
194 * a choice since we can't see the old mapping when validating an
195 * alter.
196 */
197 if (!superuser() && !pw_required)
199 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
200 errmsg("password_required=false is superuser-only"),
201 errhint("User mappings with the password_required option set to false may only be created or modified by the superuser.")));
202 }
203 else if (strcmp(def->defname, "sslcert") == 0 ||
204 strcmp(def->defname, "sslkey") == 0)
205 {
206 /* similarly for sslcert / sslkey on user mapping */
207 if (catalog == UserMappingRelationId && !superuser())
209 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
210 errmsg("sslcert and sslkey are superuser-only"),
211 errhint("User mappings with the sslcert or sslkey options set may only be created or modified by the superuser.")));
212 }
213 else if (strcmp(def->defname, "analyze_sampling") == 0)
214 {
215 char *value;
216
217 value = defGetString(def);
218
219 /* we recognize off/auto/random/system/bernoulli */
220 if (strcmp(value, "off") != 0 &&
221 strcmp(value, "auto") != 0 &&
222 strcmp(value, "random") != 0 &&
223 strcmp(value, "system") != 0 &&
224 strcmp(value, "bernoulli") != 0)
226 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
227 errmsg("invalid value for string option \"%s\": %s",
228 def->defname, value)));
229 }
230 }
231
233}
234
235/*
236 * Initialize option lists.
237 */
238static void
240{
241 int num_libpq_opts;
242 PQconninfoOption *lopt;
243 PgFdwOption *popt;
244
245 /* non-libpq FDW-specific FDW options */
246 static const PgFdwOption non_libpq_options[] = {
247 {"schema_name", ForeignTableRelationId, false},
248 {"table_name", ForeignTableRelationId, false},
249 {"column_name", AttributeRelationId, false},
250 /* use_remote_estimate is available on both server and table */
251 {"use_remote_estimate", ForeignServerRelationId, false},
252 {"use_remote_estimate", ForeignTableRelationId, false},
253 /* cost factors */
254 {"fdw_startup_cost", ForeignServerRelationId, false},
255 {"fdw_tuple_cost", ForeignServerRelationId, false},
256 /* shippable extensions */
257 {"extensions", ForeignServerRelationId, false},
258 /* updatable is available on both server and table */
259 {"updatable", ForeignServerRelationId, false},
260 {"updatable", ForeignTableRelationId, false},
261 /* truncatable is available on both server and table */
262 {"truncatable", ForeignServerRelationId, false},
263 {"truncatable", ForeignTableRelationId, false},
264 /* fetch_size is available on both server and table */
265 {"fetch_size", ForeignServerRelationId, false},
266 {"fetch_size", ForeignTableRelationId, false},
267 /* batch_size is available on both server and table */
268 {"batch_size", ForeignServerRelationId, false},
269 {"batch_size", ForeignTableRelationId, false},
270 /* async_capable is available on both server and table */
271 {"async_capable", ForeignServerRelationId, false},
272 {"async_capable", ForeignTableRelationId, false},
273 {"parallel_commit", ForeignServerRelationId, false},
274 {"parallel_abort", ForeignServerRelationId, false},
275 {"keep_connections", ForeignServerRelationId, false},
276 {"password_required", UserMappingRelationId, false},
277
278 /* sampling is available on both server and table */
279 {"analyze_sampling", ForeignServerRelationId, false},
280 {"analyze_sampling", ForeignTableRelationId, false},
281
282 /*
283 * sslcert and sslkey are in fact libpq options, but we repeat them
284 * here to allow them to appear in both foreign server context (when
285 * we generate libpq options) and user mapping context (from here).
286 */
287 {"sslcert", UserMappingRelationId, true},
288 {"sslkey", UserMappingRelationId, true},
289
290 /*
291 * gssdelegation is also a libpq option but should be allowed in a
292 * user mapping context too
293 */
294 {"gssdelegation", UserMappingRelationId, true},
295
296 {NULL, InvalidOid, false}
297 };
298
299 /* Prevent redundant initialization. */
301 return;
302
303 /*
304 * Get list of valid libpq options.
305 *
306 * To avoid unnecessary work, we get the list once and use it throughout
307 * the lifetime of this backend process. We don't need to care about
308 * memory context issues, because PQconndefaults allocates with malloc.
309 */
311 if (!libpq_options) /* assume reason for failure is OOM */
313 (errcode(ERRCODE_FDW_OUT_OF_MEMORY),
314 errmsg("out of memory"),
315 errdetail("Could not get libpq's default connection options.")));
316
317 /* Count how many libpq options are available. */
318 num_libpq_opts = 0;
319 for (lopt = libpq_options; lopt->keyword; lopt++)
320 num_libpq_opts++;
321
322 /*
323 * Construct an array which consists of all valid options for
324 * postgres_fdw, by appending FDW-specific options to libpq options.
325 *
326 * We use plain malloc here to allocate postgres_fdw_options because it
327 * lives as long as the backend process does. Besides, keeping
328 * libpq_options in memory allows us to avoid copying every keyword
329 * string.
330 */
332 malloc(sizeof(PgFdwOption) * num_libpq_opts +
333 sizeof(non_libpq_options));
334 if (postgres_fdw_options == NULL)
336 (errcode(ERRCODE_FDW_OUT_OF_MEMORY),
337 errmsg("out of memory")));
338
340 for (lopt = libpq_options; lopt->keyword; lopt++)
341 {
342 /* Hide debug options, as well as settings we override internally. */
343 if (strchr(lopt->dispchar, 'D') ||
344 strcmp(lopt->keyword, "fallback_application_name") == 0 ||
345 strcmp(lopt->keyword, "client_encoding") == 0)
346 continue;
347
348 /* We don't have to copy keyword string, as described above. */
349 popt->keyword = lopt->keyword;
350
351 /*
352 * "user" and any secret options are allowed only on user mappings.
353 * Everything else is a server option.
354 */
355 if (strcmp(lopt->keyword, "user") == 0 || strchr(lopt->dispchar, '*'))
356 popt->optcontext = UserMappingRelationId;
357 else
358 popt->optcontext = ForeignServerRelationId;
359 popt->is_libpq_opt = true;
360
361 popt++;
362 }
363
364 /* Append FDW-specific options and dummy terminator. */
365 memcpy(popt, non_libpq_options, sizeof(non_libpq_options));
366}
367
368/*
369 * Check whether the given option is one of the valid postgres_fdw options.
370 * context is the Oid of the catalog holding the object the option is for.
371 */
372static bool
373is_valid_option(const char *keyword, Oid context)
374{
375 PgFdwOption *opt;
376
377 Assert(postgres_fdw_options); /* must be initialized already */
378
379 for (opt = postgres_fdw_options; opt->keyword; opt++)
380 {
381 if (context == opt->optcontext && strcmp(opt->keyword, keyword) == 0)
382 return true;
383 }
384
385 return false;
386}
387
388/*
389 * Check whether the given option is one of the valid libpq options.
390 */
391static bool
392is_libpq_option(const char *keyword)
393{
394 PgFdwOption *opt;
395
396 Assert(postgres_fdw_options); /* must be initialized already */
397
398 for (opt = postgres_fdw_options; opt->keyword; opt++)
399 {
400 if (opt->is_libpq_opt && strcmp(opt->keyword, keyword) == 0)
401 return true;
402 }
403
404 return false;
405}
406
407/*
408 * Generate key-value arrays which include only libpq options from the
409 * given list (which can contain any kind of options). Caller must have
410 * allocated large-enough arrays. Returns number of options found.
411 */
412int
413ExtractConnectionOptions(List *defelems, const char **keywords,
414 const char **values)
415{
416 ListCell *lc;
417 int i;
418
419 /* Build our options lists if we didn't yet. */
421
422 i = 0;
423 foreach(lc, defelems)
424 {
425 DefElem *d = (DefElem *) lfirst(lc);
426
427 if (is_libpq_option(d->defname))
428 {
429 keywords[i] = d->defname;
430 values[i] = defGetString(d);
431 i++;
432 }
433 }
434 return i;
435}
436
437/*
438 * Parse a comma-separated string and return a List of the OIDs of the
439 * extensions named in the string. If any names in the list cannot be
440 * found, report a warning if warnOnMissing is true, else just silently
441 * ignore them.
442 */
443List *
444ExtractExtensionList(const char *extensionsString, bool warnOnMissing)
445{
446 List *extensionOids = NIL;
447 List *extlist;
448 ListCell *lc;
449
450 /* SplitIdentifierString scribbles on its input, so pstrdup first */
451 if (!SplitIdentifierString(pstrdup(extensionsString), ',', &extlist))
452 {
453 /* syntax error in name list */
455 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
456 errmsg("parameter \"%s\" must be a list of extension names",
457 "extensions")));
458 }
459
460 foreach(lc, extlist)
461 {
462 const char *extension_name = (const char *) lfirst(lc);
463 Oid extension_oid = get_extension_oid(extension_name, true);
464
465 if (OidIsValid(extension_oid))
466 {
467 extensionOids = lappend_oid(extensionOids, extension_oid);
468 }
469 else if (warnOnMissing)
470 {
472 (errcode(ERRCODE_UNDEFINED_OBJECT),
473 errmsg("extension \"%s\" is not installed",
474 extension_name)));
475 }
476 }
477
478 list_free(extlist);
479 return extensionOids;
480}
481
482/*
483 * Replace escape sequences beginning with % character in the given
484 * application_name with status information, and return it.
485 *
486 * This function always returns a palloc'd string, so the caller is
487 * responsible for pfreeing it.
488 */
489char *
490process_pgfdw_appname(const char *appname)
491{
492 const char *p;
494
496
497 for (p = appname; *p != '\0'; p++)
498 {
499 if (*p != '%')
500 {
501 /* literal char, just copy */
503 continue;
504 }
505
506 /* must be a '%', so skip to the next char */
507 p++;
508 if (*p == '\0')
509 break; /* format error - ignore it */
510 else if (*p == '%')
511 {
512 /* string contains %% */
514 continue;
515 }
516
517 /* process the option */
518 switch (*p)
519 {
520 case 'a':
522 break;
523 case 'c':
525 break;
526 case 'C':
528 break;
529 case 'd':
530 if (MyProcPort)
531 {
532 const char *dbname = MyProcPort->database_name;
533
534 if (dbname)
536 else
537 appendStringInfoString(&buf, "[unknown]");
538 }
539 break;
540 case 'p':
542 break;
543 case 'u':
544 if (MyProcPort)
545 {
546 const char *username = MyProcPort->user_name;
547
548 if (username)
550 else
551 appendStringInfoString(&buf, "[unknown]");
552 }
553 break;
554 default:
555 /* format error - ignore it */
556 break;
557 }
558 }
559
560 return buf.data;
561}
562
563/*
564 * Module load callback
565 */
566void
568{
569 /*
570 * Unlike application_name GUC, don't set GUC_IS_NAME flag nor check_hook
571 * to allow postgres_fdw.application_name to be any string more than
572 * NAMEDATALEN characters and to include non-ASCII characters. Instead,
573 * remote server truncates application_name of remote connection to less
574 * than NAMEDATALEN and replaces any non-ASCII characters in it with a '?'
575 * character.
576 */
577 DefineCustomStringVariable("postgres_fdw.application_name",
578 "Sets the application name to be used on the remote server.",
579 NULL,
581 NULL,
583 0,
584 NULL,
585 NULL,
586 NULL);
587
588 MarkGUCPrefixReserved("postgres_fdw");
589}
static Datum values[MAXATTR]
Definition: bootstrap.c:151
#define INT64_HEX_FORMAT
Definition: c.h:505
#define Assert(condition)
Definition: c.h:812
#define OidIsValid(objectId)
Definition: c.h:729
void _PG_init(void)
Definition: option.c:567
static bool is_valid_option(const char *keyword, Oid context)
Definition: option.c:373
static PQconninfoOption * libpq_options
Definition: option.c:46
int ExtractConnectionOptions(List *defelems, const char **keywords, const char **values)
Definition: option.c:413
static bool is_libpq_option(const char *keyword)
Definition: option.c:392
Datum postgres_fdw_validator(PG_FUNCTION_ARGS)
Definition: option.c:71
List * ExtractExtensionList(const char *extensionsString, bool warnOnMissing)
Definition: option.c:444
static PgFdwOption * postgres_fdw_options
Definition: option.c:40
struct PgFdwOption PgFdwOption
PG_FUNCTION_INFO_V1(postgres_fdw_validator)
char * pgfdw_application_name
Definition: option.c:51
char * process_pgfdw_appname(const char *appname)
Definition: option.c:490
static void InitPgFdwOptions(void)
Definition: option.c:239
char * defGetString(DefElem *def)
Definition: define.c:35
bool defGetBoolean(DefElem *def)
Definition: define.c:94
int errdetail(const char *fmt,...)
Definition: elog.c:1203
int errhint(const char *fmt,...)
Definition: elog.c:1317
int errcode(int sqlerrcode)
Definition: elog.c:853
int errmsg(const char *fmt,...)
Definition: elog.c:1070
#define WARNING
Definition: elog.h:36
#define ERROR
Definition: elog.h:39
#define ereport(elevel,...)
Definition: elog.h:149
Oid get_extension_oid(const char *extname, bool missing_ok)
Definition: extension.c:158
PQconninfoOption * PQconndefaults(void)
Definition: fe-connect.c:1883
#define PG_RETURN_VOID()
Definition: fmgr.h:349
#define PG_GETARG_OID(n)
Definition: fmgr.h:275
#define PG_GETARG_DATUM(n)
Definition: fmgr.h:268
#define PG_FUNCTION_ARGS
Definition: fmgr.h:193
int MyProcPid
Definition: globals.c:46
struct Port * MyProcPort
Definition: globals.c:50
pg_time_t MyStartTime
Definition: globals.c:47
bool parse_int(const char *value, int *result, int flags, const char **hintmsg)
Definition: guc.c:2871
void DefineCustomStringVariable(const char *name, const char *short_desc, const char *long_desc, char **valueAddr, const char *bootValue, GucContext context, int flags, GucStringCheckHook check_hook, GucStringAssignHook assign_hook, GucShowHook show_hook)
Definition: guc.c:5218
bool parse_real(const char *value, double *result, int flags, const char **hintmsg)
Definition: guc.c:2961
void MarkGUCPrefixReserved(const char *className)
Definition: guc.c:5279
@ PGC_USERSET
Definition: guc.h:75
char * cluster_name
Definition: guc_tables.c:537
char * application_name
Definition: guc_tables.c:543
#define malloc(a)
Definition: header.h:50
struct parser_state match_state[5]
static struct @161 value
static char * username
Definition: initdb.c:153
int i
Definition: isn.c:72
static const JsonPathKeyword keywords[]
List * lappend_oid(List *list, Oid datum)
Definition: list.c:375
void list_free(List *list)
Definition: list.c:1546
char * pstrdup(const char *in)
Definition: mcxt.c:1696
#define lfirst(lc)
Definition: pg_list.h:172
#define NIL
Definition: pg_list.h:68
static char * buf
Definition: pg_test_fsync.c:72
uintptr_t Datum
Definition: postgres.h:64
#define InvalidOid
Definition: postgres_ext.h:36
unsigned int Oid
Definition: postgres_ext.h:31
tree context
Definition: radixtree.h:1837
List * untransformRelOptions(Datum options)
Definition: reloptions.c:1331
char * dbname
Definition: streamutil.c:50
void appendStringInfo(StringInfo str, const char *fmt,...)
Definition: stringinfo.c:94
void appendStringInfoString(StringInfo str, const char *s)
Definition: stringinfo.c:179
void appendStringInfoChar(StringInfo str, char ch)
Definition: stringinfo.c:191
void initStringInfo(StringInfo str)
Definition: stringinfo.c:56
char * defname
Definition: parsenodes.h:817
Definition: pg_list.h:54
Oid optcontext
Definition: option.c:32
const char * keyword
Definition: option.c:31
bool is_libpq_opt
Definition: option.c:33
char * user_name
Definition: libpq-be.h:152
char * database_name
Definition: libpq-be.h:151
bool superuser(void)
Definition: superuser.c:46
const char * getClosestMatch(ClosestMatchState *state)
Definition: varlena.c:6256
bool SplitIdentifierString(char *rawstring, char separator, List **namelist)
Definition: varlena.c:3432
void initClosestMatch(ClosestMatchState *state, const char *source, int max_d)
Definition: varlena.c:6201
void updateClosestMatch(ClosestMatchState *state, const char *candidate)
Definition: varlena.c:6221