Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * misc.c
4 : *
5 : *
6 : * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
7 : * Portions Copyright (c) 1994, Regents of the University of California
8 : *
9 : *
10 : * IDENTIFICATION
11 : * src/backend/utils/adt/misc.c
12 : *
13 : *-------------------------------------------------------------------------
14 : */
15 : #include "postgres.h"
16 :
17 : #include <sys/file.h>
18 : #include <sys/stat.h>
19 : #include <dirent.h>
20 : #include <fcntl.h>
21 : #include <math.h>
22 : #include <unistd.h>
23 :
24 : #include "access/htup_details.h"
25 : #include "access/sysattr.h"
26 : #include "access/table.h"
27 : #include "catalog/pg_tablespace.h"
28 : #include "catalog/pg_type.h"
29 : #include "catalog/system_fk_info.h"
30 : #include "commands/tablespace.h"
31 : #include "common/keywords.h"
32 : #include "funcapi.h"
33 : #include "miscadmin.h"
34 : #include "nodes/miscnodes.h"
35 : #include "parser/parse_type.h"
36 : #include "parser/scansup.h"
37 : #include "pgstat.h"
38 : #include "postmaster/syslogger.h"
39 : #include "rewrite/rewriteHandler.h"
40 : #include "storage/fd.h"
41 : #include "storage/latch.h"
42 : #include "tcop/tcopprot.h"
43 : #include "utils/builtins.h"
44 : #include "utils/fmgroids.h"
45 : #include "utils/lsyscache.h"
46 : #include "utils/ruleutils.h"
47 : #include "utils/syscache.h"
48 : #include "utils/timestamp.h"
49 :
50 :
51 : /*
52 : * structure to cache metadata needed in pg_input_is_valid_common
53 : */
54 : typedef struct ValidIOData
55 : {
56 : Oid typoid;
57 : int32 typmod;
58 : bool typname_constant;
59 : Oid typiofunc;
60 : Oid typioparam;
61 : FmgrInfo inputproc;
62 : } ValidIOData;
63 :
64 : static bool pg_input_is_valid_common(FunctionCallInfo fcinfo,
65 : text *txt, text *typname,
66 : ErrorSaveContext *escontext);
67 :
68 :
69 : /*
70 : * Common subroutine for num_nulls() and num_nonnulls().
71 : * Returns true if successful, false if function should return NULL.
72 : * If successful, total argument count and number of nulls are
73 : * returned into *nargs and *nulls.
74 : */
75 : static bool
76 120 : count_nulls(FunctionCallInfo fcinfo,
77 : int32 *nargs, int32 *nulls)
78 : {
79 120 : int32 count = 0;
80 : int i;
81 :
82 : /* Did we get a VARIADIC array argument, or separate arguments? */
83 120 : if (get_fn_expr_variadic(fcinfo->flinfo))
84 : {
85 : ArrayType *arr;
86 : int ndims,
87 : nitems,
88 : *dims;
89 : bits8 *bitmap;
90 :
91 : Assert(PG_NARGS() == 1);
92 :
93 : /*
94 : * If we get a null as VARIADIC array argument, we can't say anything
95 : * useful about the number of elements, so return NULL. This behavior
96 : * is consistent with other variadic functions - see concat_internal.
97 : */
98 60 : if (PG_ARGISNULL(0))
99 12 : return false;
100 :
101 : /*
102 : * Non-null argument had better be an array. We assume that any call
103 : * context that could let get_fn_expr_variadic return true will have
104 : * checked that a VARIADIC-labeled parameter actually is an array. So
105 : * it should be okay to just Assert that it's an array rather than
106 : * doing a full-fledged error check.
107 : */
108 : Assert(OidIsValid(get_base_element_type(get_fn_expr_argtype(fcinfo->flinfo, 0))));
109 :
110 : /* OK, safe to fetch the array value */
111 48 : arr = PG_GETARG_ARRAYTYPE_P(0);
112 :
113 : /* Count the array elements */
114 48 : ndims = ARR_NDIM(arr);
115 48 : dims = ARR_DIMS(arr);
116 48 : nitems = ArrayGetNItems(ndims, dims);
117 :
118 : /* Count those that are NULL */
119 48 : bitmap = ARR_NULLBITMAP(arr);
120 48 : if (bitmap)
121 : {
122 24 : int bitmask = 1;
123 :
124 1272 : for (i = 0; i < nitems; i++)
125 : {
126 1248 : if ((*bitmap & bitmask) == 0)
127 24 : count++;
128 :
129 1248 : bitmask <<= 1;
130 1248 : if (bitmask == 0x100)
131 : {
132 144 : bitmap++;
133 144 : bitmask = 1;
134 : }
135 : }
136 : }
137 :
138 48 : *nargs = nitems;
139 48 : *nulls = count;
140 : }
141 : else
142 : {
143 : /* Separate arguments, so just count 'em */
144 204 : for (i = 0; i < PG_NARGS(); i++)
145 : {
146 144 : if (PG_ARGISNULL(i))
147 84 : count++;
148 : }
149 :
150 60 : *nargs = PG_NARGS();
151 60 : *nulls = count;
152 : }
153 :
154 108 : return true;
155 : }
156 :
157 : /*
158 : * num_nulls()
159 : * Count the number of NULL arguments
160 : */
161 : Datum
162 60 : pg_num_nulls(PG_FUNCTION_ARGS)
163 : {
164 : int32 nargs,
165 : nulls;
166 :
167 60 : if (!count_nulls(fcinfo, &nargs, &nulls))
168 6 : PG_RETURN_NULL();
169 :
170 54 : PG_RETURN_INT32(nulls);
171 : }
172 :
173 : /*
174 : * num_nonnulls()
175 : * Count the number of non-NULL arguments
176 : */
177 : Datum
178 60 : pg_num_nonnulls(PG_FUNCTION_ARGS)
179 : {
180 : int32 nargs,
181 : nulls;
182 :
183 60 : if (!count_nulls(fcinfo, &nargs, &nulls))
184 6 : PG_RETURN_NULL();
185 :
186 54 : PG_RETURN_INT32(nargs - nulls);
187 : }
188 :
189 : /*
190 : * error_on_null()
191 : * Check if the input is the NULL value
192 : */
193 : Datum
194 36 : pg_error_on_null(PG_FUNCTION_ARGS)
195 : {
196 36 : if (PG_ARGISNULL(0))
197 12 : ereport(ERROR,
198 : (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
199 : errmsg("null value not allowed")));
200 :
201 24 : PG_RETURN_DATUM(PG_GETARG_DATUM(0));
202 : }
203 :
204 : /*
205 : * current_database()
206 : * Expose the current database to the user
207 : */
208 : Datum
209 7728 : current_database(PG_FUNCTION_ARGS)
210 : {
211 : Name db;
212 :
213 7728 : db = (Name) palloc(NAMEDATALEN);
214 :
215 7728 : namestrcpy(db, get_database_name(MyDatabaseId));
216 7728 : PG_RETURN_NAME(db);
217 : }
218 :
219 :
220 : /*
221 : * current_query()
222 : * Expose the current query to the user (useful in stored procedures)
223 : * We might want to use ActivePortal->sourceText someday.
224 : */
225 : Datum
226 0 : current_query(PG_FUNCTION_ARGS)
227 : {
228 : /* there is no easy way to access the more concise 'query_string' */
229 0 : if (debug_query_string)
230 0 : PG_RETURN_TEXT_P(cstring_to_text(debug_query_string));
231 : else
232 0 : PG_RETURN_NULL();
233 : }
234 :
235 : /* Function to find out which databases make use of a tablespace */
236 :
237 : Datum
238 6 : pg_tablespace_databases(PG_FUNCTION_ARGS)
239 : {
240 6 : Oid tablespaceOid = PG_GETARG_OID(0);
241 6 : ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
242 : char *location;
243 : DIR *dirdesc;
244 : struct dirent *de;
245 :
246 6 : InitMaterializedSRF(fcinfo, MAT_SRF_USE_EXPECTED_DESC);
247 :
248 6 : if (tablespaceOid == GLOBALTABLESPACE_OID)
249 : {
250 0 : ereport(WARNING,
251 : (errmsg("global tablespace never has databases")));
252 : /* return empty tuplestore */
253 0 : return (Datum) 0;
254 : }
255 :
256 6 : if (tablespaceOid == DEFAULTTABLESPACE_OID)
257 6 : location = "base";
258 : else
259 0 : location = psprintf("%s/%u/%s", PG_TBLSPC_DIR, tablespaceOid,
260 : TABLESPACE_VERSION_DIRECTORY);
261 :
262 6 : dirdesc = AllocateDir(location);
263 :
264 6 : if (!dirdesc)
265 : {
266 : /* the only expected error is ENOENT */
267 0 : if (errno != ENOENT)
268 0 : ereport(ERROR,
269 : (errcode_for_file_access(),
270 : errmsg("could not open directory \"%s\": %m",
271 : location)));
272 0 : ereport(WARNING,
273 : (errmsg("%u is not a tablespace OID", tablespaceOid)));
274 : /* return empty tuplestore */
275 0 : return (Datum) 0;
276 : }
277 :
278 54 : while ((de = ReadDir(dirdesc, location)) != NULL)
279 : {
280 48 : Oid datOid = atooid(de->d_name);
281 : char *subdir;
282 : bool isempty;
283 : Datum values[1];
284 : bool nulls[1];
285 :
286 : /* this test skips . and .., but is awfully weak */
287 48 : if (!datOid)
288 18 : continue;
289 :
290 : /* if database subdir is empty, don't report tablespace as used */
291 :
292 30 : subdir = psprintf("%s/%s", location, de->d_name);
293 30 : isempty = directory_is_empty(subdir);
294 30 : pfree(subdir);
295 :
296 30 : if (isempty)
297 0 : continue; /* indeed, nothing in it */
298 :
299 30 : values[0] = ObjectIdGetDatum(datOid);
300 30 : nulls[0] = false;
301 :
302 30 : tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc,
303 : values, nulls);
304 : }
305 :
306 6 : FreeDir(dirdesc);
307 6 : return (Datum) 0;
308 : }
309 :
310 :
311 : /*
312 : * pg_tablespace_location - get location for a tablespace
313 : */
314 : Datum
315 264 : pg_tablespace_location(PG_FUNCTION_ARGS)
316 : {
317 264 : Oid tablespaceOid = PG_GETARG_OID(0);
318 : char sourcepath[MAXPGPATH];
319 : char targetpath[MAXPGPATH];
320 : int rllen;
321 : struct stat st;
322 :
323 : /*
324 : * It's useful to apply this function to pg_class.reltablespace, wherein
325 : * zero means "the database's default tablespace". So, rather than
326 : * throwing an error for zero, we choose to assume that's what is meant.
327 : */
328 264 : if (tablespaceOid == InvalidOid)
329 0 : tablespaceOid = MyDatabaseTableSpace;
330 :
331 : /*
332 : * Return empty string for the cluster's default tablespaces
333 : */
334 264 : if (tablespaceOid == DEFAULTTABLESPACE_OID ||
335 : tablespaceOid == GLOBALTABLESPACE_OID)
336 186 : PG_RETURN_TEXT_P(cstring_to_text(""));
337 :
338 : /*
339 : * Find the location of the tablespace by reading the symbolic link that
340 : * is in pg_tblspc/<oid>.
341 : */
342 78 : snprintf(sourcepath, sizeof(sourcepath), "%s/%u", PG_TBLSPC_DIR, tablespaceOid);
343 :
344 : /*
345 : * Before reading the link, check if the source path is a link or a
346 : * junction point. Note that a directory is possible for a tablespace
347 : * created with allow_in_place_tablespaces enabled. If a directory is
348 : * found, a relative path to the data directory is returned.
349 : */
350 78 : if (lstat(sourcepath, &st) < 0)
351 : {
352 0 : ereport(ERROR,
353 : (errcode_for_file_access(),
354 : errmsg("could not stat file \"%s\": %m",
355 : sourcepath)));
356 : }
357 :
358 78 : if (!S_ISLNK(st.st_mode))
359 74 : PG_RETURN_TEXT_P(cstring_to_text(sourcepath));
360 :
361 : /*
362 : * In presence of a link or a junction point, return the path pointing to.
363 : */
364 4 : rllen = readlink(sourcepath, targetpath, sizeof(targetpath));
365 4 : if (rllen < 0)
366 0 : ereport(ERROR,
367 : (errcode_for_file_access(),
368 : errmsg("could not read symbolic link \"%s\": %m",
369 : sourcepath)));
370 4 : if (rllen >= sizeof(targetpath))
371 0 : ereport(ERROR,
372 : (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
373 : errmsg("symbolic link \"%s\" target is too long",
374 : sourcepath)));
375 4 : targetpath[rllen] = '\0';
376 :
377 4 : PG_RETURN_TEXT_P(cstring_to_text(targetpath));
378 : }
379 :
380 : /*
381 : * pg_sleep - delay for N seconds
382 : */
383 : Datum
384 236 : pg_sleep(PG_FUNCTION_ARGS)
385 : {
386 236 : float8 secs = PG_GETARG_FLOAT8(0);
387 : int64 usecs;
388 : TimestampTz endtime;
389 :
390 : /*
391 : * Convert the delay to int64 microseconds, rounding up any fraction, and
392 : * silently limiting it to PG_INT64_MAX/2 microseconds (about 150K years)
393 : * to ensure the computation of endtime won't overflow. Historically
394 : * we've treated NaN as "no wait", not an error, so keep that behavior.
395 : */
396 236 : if (isnan(secs) || secs <= 0.0)
397 0 : PG_RETURN_VOID();
398 236 : secs *= USECS_PER_SEC; /* we assume overflow will produce +Inf */
399 236 : secs = ceil(secs); /* round up any fractional microsecond */
400 236 : usecs = (int64) Min(secs, (float8) (PG_INT64_MAX / 2));
401 :
402 : /*
403 : * We sleep using WaitLatch, to ensure that we'll wake up promptly if an
404 : * important signal (such as SIGALRM or SIGINT) arrives. Because
405 : * WaitLatch's upper limit of delay is INT_MAX milliseconds, and the user
406 : * might ask for more than that, we sleep for at most 10 minutes and then
407 : * loop.
408 : *
409 : * By computing the intended stop time initially, we avoid accumulation of
410 : * extra delay across multiple sleeps. This also ensures we won't delay
411 : * less than the specified time when WaitLatch is terminated early by a
412 : * non-query-canceling signal such as SIGHUP.
413 : */
414 236 : endtime = GetCurrentTimestamp() + usecs;
415 :
416 : for (;;)
417 246 : {
418 : TimestampTz delay;
419 : long delay_ms;
420 :
421 482 : CHECK_FOR_INTERRUPTS();
422 :
423 456 : delay = endtime - GetCurrentTimestamp();
424 456 : if (delay >= 600 * USECS_PER_SEC)
425 0 : delay_ms = 600000;
426 456 : else if (delay > 0)
427 246 : delay_ms = (long) ((delay + 999) / 1000);
428 : else
429 210 : break;
430 :
431 246 : (void) WaitLatch(MyLatch,
432 : WL_LATCH_SET | WL_TIMEOUT | WL_EXIT_ON_PM_DEATH,
433 : delay_ms,
434 : WAIT_EVENT_PG_SLEEP);
435 246 : ResetLatch(MyLatch);
436 : }
437 :
438 210 : PG_RETURN_VOID();
439 : }
440 :
441 : /* Function to return the list of grammar keywords */
442 : Datum
443 0 : pg_get_keywords(PG_FUNCTION_ARGS)
444 : {
445 : FuncCallContext *funcctx;
446 :
447 0 : if (SRF_IS_FIRSTCALL())
448 : {
449 : MemoryContext oldcontext;
450 : TupleDesc tupdesc;
451 :
452 0 : funcctx = SRF_FIRSTCALL_INIT();
453 0 : oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
454 :
455 0 : if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
456 0 : elog(ERROR, "return type must be a row type");
457 0 : funcctx->tuple_desc = tupdesc;
458 0 : funcctx->attinmeta = TupleDescGetAttInMetadata(tupdesc);
459 :
460 0 : MemoryContextSwitchTo(oldcontext);
461 : }
462 :
463 0 : funcctx = SRF_PERCALL_SETUP();
464 :
465 0 : if (funcctx->call_cntr < ScanKeywords.num_keywords)
466 : {
467 : char *values[5];
468 : HeapTuple tuple;
469 :
470 : /* cast-away-const is ugly but alternatives aren't much better */
471 0 : values[0] = unconstify(char *,
472 : GetScanKeyword(funcctx->call_cntr,
473 : &ScanKeywords));
474 :
475 0 : switch (ScanKeywordCategories[funcctx->call_cntr])
476 : {
477 0 : case UNRESERVED_KEYWORD:
478 0 : values[1] = "U";
479 0 : values[3] = _("unreserved");
480 0 : break;
481 0 : case COL_NAME_KEYWORD:
482 0 : values[1] = "C";
483 0 : values[3] = _("unreserved (cannot be function or type name)");
484 0 : break;
485 0 : case TYPE_FUNC_NAME_KEYWORD:
486 0 : values[1] = "T";
487 0 : values[3] = _("reserved (can be function or type name)");
488 0 : break;
489 0 : case RESERVED_KEYWORD:
490 0 : values[1] = "R";
491 0 : values[3] = _("reserved");
492 0 : break;
493 0 : default: /* shouldn't be possible */
494 0 : values[1] = NULL;
495 0 : values[3] = NULL;
496 0 : break;
497 : }
498 :
499 0 : if (ScanKeywordBareLabel[funcctx->call_cntr])
500 : {
501 0 : values[2] = "true";
502 0 : values[4] = _("can be bare label");
503 : }
504 : else
505 : {
506 0 : values[2] = "false";
507 0 : values[4] = _("requires AS");
508 : }
509 :
510 0 : tuple = BuildTupleFromCStrings(funcctx->attinmeta, values);
511 :
512 0 : SRF_RETURN_NEXT(funcctx, HeapTupleGetDatum(tuple));
513 : }
514 :
515 0 : SRF_RETURN_DONE(funcctx);
516 : }
517 :
518 :
519 : /* Function to return the list of catalog foreign key relationships */
520 : Datum
521 1320 : pg_get_catalog_foreign_keys(PG_FUNCTION_ARGS)
522 : {
523 : FuncCallContext *funcctx;
524 : FmgrInfo *arrayinp;
525 :
526 1320 : if (SRF_IS_FIRSTCALL())
527 : {
528 : MemoryContext oldcontext;
529 : TupleDesc tupdesc;
530 :
531 6 : funcctx = SRF_FIRSTCALL_INIT();
532 6 : oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
533 :
534 6 : if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
535 0 : elog(ERROR, "return type must be a row type");
536 6 : funcctx->tuple_desc = BlessTupleDesc(tupdesc);
537 :
538 : /*
539 : * We use array_in to convert the C strings in sys_fk_relationships[]
540 : * to text arrays. But we cannot use DirectFunctionCallN to call
541 : * array_in, and it wouldn't be very efficient if we could. Fill an
542 : * FmgrInfo to use for the call.
543 : */
544 6 : arrayinp = (FmgrInfo *) palloc(sizeof(FmgrInfo));
545 6 : fmgr_info(F_ARRAY_IN, arrayinp);
546 6 : funcctx->user_fctx = arrayinp;
547 :
548 6 : MemoryContextSwitchTo(oldcontext);
549 : }
550 :
551 1320 : funcctx = SRF_PERCALL_SETUP();
552 1320 : arrayinp = (FmgrInfo *) funcctx->user_fctx;
553 :
554 1320 : if (funcctx->call_cntr < lengthof(sys_fk_relationships))
555 : {
556 1314 : const SysFKRelationship *fkrel = &sys_fk_relationships[funcctx->call_cntr];
557 : Datum values[6];
558 : bool nulls[6];
559 : HeapTuple tuple;
560 :
561 1314 : memset(nulls, false, sizeof(nulls));
562 :
563 1314 : values[0] = ObjectIdGetDatum(fkrel->fk_table);
564 1314 : values[1] = FunctionCall3(arrayinp,
565 : CStringGetDatum(fkrel->fk_columns),
566 : ObjectIdGetDatum(TEXTOID),
567 : Int32GetDatum(-1));
568 1314 : values[2] = ObjectIdGetDatum(fkrel->pk_table);
569 1314 : values[3] = FunctionCall3(arrayinp,
570 : CStringGetDatum(fkrel->pk_columns),
571 : ObjectIdGetDatum(TEXTOID),
572 : Int32GetDatum(-1));
573 1314 : values[4] = BoolGetDatum(fkrel->is_array);
574 1314 : values[5] = BoolGetDatum(fkrel->is_opt);
575 :
576 1314 : tuple = heap_form_tuple(funcctx->tuple_desc, values, nulls);
577 :
578 1314 : SRF_RETURN_NEXT(funcctx, HeapTupleGetDatum(tuple));
579 : }
580 :
581 6 : SRF_RETURN_DONE(funcctx);
582 : }
583 :
584 :
585 : /*
586 : * Return the type of the argument.
587 : */
588 : Datum
589 1682 : pg_typeof(PG_FUNCTION_ARGS)
590 : {
591 1682 : PG_RETURN_OID(get_fn_expr_argtype(fcinfo->flinfo, 0));
592 : }
593 :
594 :
595 : /*
596 : * Return the base type of the argument.
597 : * If the given type is a domain, return its base type;
598 : * otherwise return the type's own OID.
599 : * Return NULL if the type OID doesn't exist or points to a
600 : * non-existent base type.
601 : *
602 : * This is a SQL-callable version of getBaseType(). Unlike that function,
603 : * we don't want to fail for a bogus type OID; this is helpful to keep race
604 : * conditions from turning into query failures when scanning the catalogs.
605 : * Hence we need our own implementation.
606 : */
607 : Datum
608 18 : pg_basetype(PG_FUNCTION_ARGS)
609 : {
610 18 : Oid typid = PG_GETARG_OID(0);
611 :
612 : /*
613 : * We loop to find the bottom base type in a stack of domains.
614 : */
615 : for (;;)
616 18 : {
617 : HeapTuple tup;
618 : Form_pg_type typTup;
619 :
620 36 : tup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(typid));
621 36 : if (!HeapTupleIsValid(tup))
622 6 : PG_RETURN_NULL(); /* return NULL for bogus OID */
623 30 : typTup = (Form_pg_type) GETSTRUCT(tup);
624 30 : if (typTup->typtype != TYPTYPE_DOMAIN)
625 : {
626 : /* Not a domain, so done */
627 12 : ReleaseSysCache(tup);
628 12 : break;
629 : }
630 :
631 18 : typid = typTup->typbasetype;
632 18 : ReleaseSysCache(tup);
633 : }
634 :
635 12 : PG_RETURN_OID(typid);
636 : }
637 :
638 :
639 : /*
640 : * Implementation of the COLLATE FOR expression; returns the collation
641 : * of the argument.
642 : */
643 : Datum
644 30 : pg_collation_for(PG_FUNCTION_ARGS)
645 : {
646 : Oid typeid;
647 : Oid collid;
648 :
649 30 : typeid = get_fn_expr_argtype(fcinfo->flinfo, 0);
650 30 : if (!typeid)
651 0 : PG_RETURN_NULL();
652 30 : if (!type_is_collatable(typeid) && typeid != UNKNOWNOID)
653 6 : ereport(ERROR,
654 : (errcode(ERRCODE_DATATYPE_MISMATCH),
655 : errmsg("collations are not supported by type %s",
656 : format_type_be(typeid))));
657 :
658 24 : collid = PG_GET_COLLATION();
659 24 : if (!collid)
660 6 : PG_RETURN_NULL();
661 18 : PG_RETURN_TEXT_P(cstring_to_text(generate_collation_name(collid)));
662 : }
663 :
664 :
665 : /*
666 : * pg_relation_is_updatable - determine which update events the specified
667 : * relation supports.
668 : *
669 : * This relies on relation_is_updatable() in rewriteHandler.c, which see
670 : * for additional information.
671 : */
672 : Datum
673 894 : pg_relation_is_updatable(PG_FUNCTION_ARGS)
674 : {
675 894 : Oid reloid = PG_GETARG_OID(0);
676 894 : bool include_triggers = PG_GETARG_BOOL(1);
677 :
678 894 : PG_RETURN_INT32(relation_is_updatable(reloid, NIL, include_triggers, NULL));
679 : }
680 :
681 : /*
682 : * pg_column_is_updatable - determine whether a column is updatable
683 : *
684 : * This function encapsulates the decision about just what
685 : * information_schema.columns.is_updatable actually means. It's not clear
686 : * whether deletability of the column's relation should be required, so
687 : * we want that decision in C code where we could change it without initdb.
688 : */
689 : Datum
690 666 : pg_column_is_updatable(PG_FUNCTION_ARGS)
691 : {
692 666 : Oid reloid = PG_GETARG_OID(0);
693 666 : AttrNumber attnum = PG_GETARG_INT16(1);
694 666 : AttrNumber col = attnum - FirstLowInvalidHeapAttributeNumber;
695 666 : bool include_triggers = PG_GETARG_BOOL(2);
696 : int events;
697 :
698 : /* System columns are never updatable */
699 666 : if (attnum <= 0)
700 0 : PG_RETURN_BOOL(false);
701 :
702 666 : events = relation_is_updatable(reloid, NIL, include_triggers,
703 : bms_make_singleton(col));
704 :
705 : /* We require both updatability and deletability of the relation */
706 : #define REQ_EVENTS ((1 << CMD_UPDATE) | (1 << CMD_DELETE))
707 :
708 666 : PG_RETURN_BOOL((events & REQ_EVENTS) == REQ_EVENTS);
709 : }
710 :
711 :
712 : /*
713 : * pg_input_is_valid - test whether string is valid input for datatype.
714 : *
715 : * Returns true if OK, false if not.
716 : *
717 : * This will only work usefully if the datatype's input function has been
718 : * updated to return "soft" errors via errsave/ereturn.
719 : */
720 : Datum
721 884 : pg_input_is_valid(PG_FUNCTION_ARGS)
722 : {
723 884 : text *txt = PG_GETARG_TEXT_PP(0);
724 884 : text *typname = PG_GETARG_TEXT_PP(1);
725 884 : ErrorSaveContext escontext = {T_ErrorSaveContext};
726 :
727 884 : PG_RETURN_BOOL(pg_input_is_valid_common(fcinfo, txt, typname,
728 : &escontext));
729 : }
730 :
731 : /*
732 : * pg_input_error_info - test whether string is valid input for datatype.
733 : *
734 : * Returns NULL if OK, else the primary message, detail message, hint message
735 : * and sql error code from the error.
736 : *
737 : * This will only work usefully if the datatype's input function has been
738 : * updated to return "soft" errors via errsave/ereturn.
739 : */
740 : Datum
741 772 : pg_input_error_info(PG_FUNCTION_ARGS)
742 : {
743 772 : text *txt = PG_GETARG_TEXT_PP(0);
744 772 : text *typname = PG_GETARG_TEXT_PP(1);
745 772 : ErrorSaveContext escontext = {T_ErrorSaveContext};
746 : TupleDesc tupdesc;
747 : Datum values[4];
748 : bool isnull[4];
749 :
750 772 : if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
751 0 : elog(ERROR, "return type must be a row type");
752 :
753 : /* Enable details_wanted */
754 772 : escontext.details_wanted = true;
755 :
756 772 : if (pg_input_is_valid_common(fcinfo, txt, typname,
757 : &escontext))
758 26 : memset(isnull, true, sizeof(isnull));
759 : else
760 : {
761 : char *sqlstate;
762 :
763 : Assert(escontext.error_occurred);
764 : Assert(escontext.error_data != NULL);
765 : Assert(escontext.error_data->message != NULL);
766 :
767 716 : memset(isnull, false, sizeof(isnull));
768 :
769 716 : values[0] = CStringGetTextDatum(escontext.error_data->message);
770 :
771 716 : if (escontext.error_data->detail != NULL)
772 62 : values[1] = CStringGetTextDatum(escontext.error_data->detail);
773 : else
774 654 : isnull[1] = true;
775 :
776 716 : if (escontext.error_data->hint != NULL)
777 0 : values[2] = CStringGetTextDatum(escontext.error_data->hint);
778 : else
779 716 : isnull[2] = true;
780 :
781 716 : sqlstate = unpack_sql_state(escontext.error_data->sqlerrcode);
782 716 : values[3] = CStringGetTextDatum(sqlstate);
783 : }
784 :
785 742 : return HeapTupleGetDatum(heap_form_tuple(tupdesc, values, isnull));
786 : }
787 :
788 : /* Common subroutine for the above */
789 : static bool
790 1656 : pg_input_is_valid_common(FunctionCallInfo fcinfo,
791 : text *txt, text *typname,
792 : ErrorSaveContext *escontext)
793 : {
794 1656 : char *str = text_to_cstring(txt);
795 : ValidIOData *my_extra;
796 : Datum converted;
797 :
798 : /*
799 : * We arrange to look up the needed I/O info just once per series of
800 : * calls, assuming the data type doesn't change underneath us.
801 : */
802 1656 : my_extra = (ValidIOData *) fcinfo->flinfo->fn_extra;
803 1656 : if (my_extra == NULL)
804 : {
805 3088 : fcinfo->flinfo->fn_extra =
806 1544 : MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
807 : sizeof(ValidIOData));
808 1544 : my_extra = (ValidIOData *) fcinfo->flinfo->fn_extra;
809 1544 : my_extra->typoid = InvalidOid;
810 : /* Detect whether typname argument is constant. */
811 1544 : my_extra->typname_constant = get_fn_expr_arg_stable(fcinfo->flinfo, 1);
812 : }
813 :
814 : /*
815 : * If the typname argument is constant, we only need to parse it the first
816 : * time through.
817 : */
818 1656 : if (my_extra->typoid == InvalidOid || !my_extra->typname_constant)
819 : {
820 1580 : char *typnamestr = text_to_cstring(typname);
821 : Oid typoid;
822 :
823 : /* Parse type-name argument to obtain type OID and encoded typmod. */
824 1580 : (void) parseTypeString(typnamestr, &typoid, &my_extra->typmod, NULL);
825 :
826 : /* Update type-specific info if typoid changed. */
827 1580 : if (my_extra->typoid != typoid)
828 : {
829 1560 : getTypeInputInfo(typoid,
830 : &my_extra->typiofunc,
831 : &my_extra->typioparam);
832 1560 : fmgr_info_cxt(my_extra->typiofunc, &my_extra->inputproc,
833 1560 : fcinfo->flinfo->fn_mcxt);
834 1560 : my_extra->typoid = typoid;
835 : }
836 : }
837 :
838 : /* Now we can try to perform the conversion. */
839 1656 : return InputFunctionCallSafe(&my_extra->inputproc,
840 : str,
841 : my_extra->typioparam,
842 : my_extra->typmod,
843 : (Node *) escontext,
844 : &converted);
845 : }
846 :
847 :
848 : /*
849 : * Is character a valid identifier start?
850 : * Must match scan.l's {ident_start} character class.
851 : */
852 : static bool
853 2202 : is_ident_start(unsigned char c)
854 : {
855 : /* Underscores and ASCII letters are OK */
856 2202 : if (c == '_')
857 0 : return true;
858 2202 : if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z'))
859 2052 : return true;
860 : /* Any high-bit-set character is OK (might be part of a multibyte char) */
861 150 : if (IS_HIGHBIT_SET(c))
862 0 : return true;
863 150 : return false;
864 : }
865 :
866 : /*
867 : * Is character a valid identifier continuation?
868 : * Must match scan.l's {ident_cont} character class.
869 : */
870 : static bool
871 2052 : is_ident_cont(unsigned char c)
872 : {
873 : /* Can be digit or dollar sign ... */
874 2052 : if ((c >= '0' && c <= '9') || c == '$')
875 0 : return true;
876 : /* ... or an identifier start character */
877 2052 : return is_ident_start(c);
878 : }
879 :
880 : /*
881 : * parse_ident - parse a SQL qualified identifier into separate identifiers.
882 : * When strict mode is active (second parameter), then any chars after
883 : * the last identifier are disallowed.
884 : */
885 : Datum
886 114 : parse_ident(PG_FUNCTION_ARGS)
887 : {
888 114 : text *qualname = PG_GETARG_TEXT_PP(0);
889 114 : bool strict = PG_GETARG_BOOL(1);
890 114 : char *qualname_str = text_to_cstring(qualname);
891 114 : ArrayBuildState *astate = NULL;
892 : char *nextp;
893 114 : bool after_dot = false;
894 :
895 : /*
896 : * The code below scribbles on qualname_str in some cases, so we should
897 : * reconvert qualname if we need to show the original string in error
898 : * messages.
899 : */
900 114 : nextp = qualname_str;
901 :
902 : /* skip leading whitespace */
903 144 : while (scanner_isspace(*nextp))
904 30 : nextp++;
905 :
906 : for (;;)
907 96 : {
908 : char *curname;
909 210 : bool missing_ident = true;
910 :
911 210 : if (*nextp == '"')
912 : {
913 : char *endp;
914 :
915 60 : curname = nextp + 1;
916 : for (;;)
917 : {
918 60 : endp = strchr(nextp + 1, '"');
919 60 : if (endp == NULL)
920 0 : ereport(ERROR,
921 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
922 : errmsg("string is not a valid identifier: \"%s\"",
923 : text_to_cstring(qualname)),
924 : errdetail("String has unclosed double quotes.")));
925 60 : if (endp[1] != '"')
926 60 : break;
927 0 : memmove(endp, endp + 1, strlen(endp));
928 0 : nextp = endp;
929 : }
930 60 : nextp = endp + 1;
931 60 : *endp = '\0';
932 :
933 60 : if (endp - curname == 0)
934 0 : ereport(ERROR,
935 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
936 : errmsg("string is not a valid identifier: \"%s\"",
937 : text_to_cstring(qualname)),
938 : errdetail("Quoted identifier must not be empty.")));
939 :
940 60 : astate = accumArrayResult(astate, CStringGetTextDatum(curname),
941 : false, TEXTOID, CurrentMemoryContext);
942 60 : missing_ident = false;
943 : }
944 150 : else if (is_ident_start((unsigned char) *nextp))
945 : {
946 : char *downname;
947 : int len;
948 : text *part;
949 :
950 102 : curname = nextp++;
951 2052 : while (is_ident_cont((unsigned char) *nextp))
952 1950 : nextp++;
953 :
954 102 : len = nextp - curname;
955 :
956 : /*
957 : * We don't implicitly truncate identifiers. This is useful for
958 : * allowing the user to check for specific parts of the identifier
959 : * being too long. It's easy enough for the user to get the
960 : * truncated names by casting our output to name[].
961 : */
962 102 : downname = downcase_identifier(curname, len, false, false);
963 102 : part = cstring_to_text_with_len(downname, len);
964 102 : astate = accumArrayResult(astate, PointerGetDatum(part), false,
965 : TEXTOID, CurrentMemoryContext);
966 102 : missing_ident = false;
967 : }
968 :
969 210 : if (missing_ident)
970 : {
971 : /* Different error messages based on where we failed. */
972 48 : if (*nextp == '.')
973 18 : ereport(ERROR,
974 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
975 : errmsg("string is not a valid identifier: \"%s\"",
976 : text_to_cstring(qualname)),
977 : errdetail("No valid identifier before \".\".")));
978 30 : else if (after_dot)
979 12 : ereport(ERROR,
980 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
981 : errmsg("string is not a valid identifier: \"%s\"",
982 : text_to_cstring(qualname)),
983 : errdetail("No valid identifier after \".\".")));
984 : else
985 18 : ereport(ERROR,
986 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
987 : errmsg("string is not a valid identifier: \"%s\"",
988 : text_to_cstring(qualname))));
989 : }
990 :
991 204 : while (scanner_isspace(*nextp))
992 42 : nextp++;
993 :
994 162 : if (*nextp == '.')
995 : {
996 96 : after_dot = true;
997 96 : nextp++;
998 126 : while (scanner_isspace(*nextp))
999 30 : nextp++;
1000 : }
1001 66 : else if (*nextp == '\0')
1002 : {
1003 36 : break;
1004 : }
1005 : else
1006 : {
1007 30 : if (strict)
1008 24 : ereport(ERROR,
1009 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
1010 : errmsg("string is not a valid identifier: \"%s\"",
1011 : text_to_cstring(qualname))));
1012 6 : break;
1013 : }
1014 : }
1015 :
1016 42 : PG_RETURN_DATUM(makeArrayResult(astate, CurrentMemoryContext));
1017 : }
1018 :
1019 : /*
1020 : * pg_current_logfile
1021 : *
1022 : * Report current log file used by log collector by scanning current_logfiles.
1023 : */
1024 : Datum
1025 12 : pg_current_logfile(PG_FUNCTION_ARGS)
1026 : {
1027 : FILE *fd;
1028 : char lbuffer[MAXPGPATH];
1029 : char *logfmt;
1030 :
1031 : /* The log format parameter is optional */
1032 12 : if (PG_NARGS() == 0 || PG_ARGISNULL(0))
1033 0 : logfmt = NULL;
1034 : else
1035 : {
1036 12 : logfmt = text_to_cstring(PG_GETARG_TEXT_PP(0));
1037 :
1038 12 : if (strcmp(logfmt, "stderr") != 0 &&
1039 8 : strcmp(logfmt, "csvlog") != 0 &&
1040 4 : strcmp(logfmt, "jsonlog") != 0)
1041 0 : ereport(ERROR,
1042 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
1043 : errmsg("log format \"%s\" is not supported", logfmt),
1044 : errhint("The supported log formats are \"stderr\", \"csvlog\", and \"jsonlog\".")));
1045 : }
1046 :
1047 12 : fd = AllocateFile(LOG_METAINFO_DATAFILE, "r");
1048 12 : if (fd == NULL)
1049 : {
1050 0 : if (errno != ENOENT)
1051 0 : ereport(ERROR,
1052 : (errcode_for_file_access(),
1053 : errmsg("could not read file \"%s\": %m",
1054 : LOG_METAINFO_DATAFILE)));
1055 0 : PG_RETURN_NULL();
1056 : }
1057 :
1058 : #ifdef WIN32
1059 : /* syslogger.c writes CRLF line endings on Windows */
1060 : _setmode(_fileno(fd), _O_TEXT);
1061 : #endif
1062 :
1063 : /*
1064 : * Read the file to gather current log filename(s) registered by the
1065 : * syslogger.
1066 : */
1067 24 : while (fgets(lbuffer, sizeof(lbuffer), fd) != NULL)
1068 : {
1069 : char *log_format;
1070 : char *log_filepath;
1071 : char *nlpos;
1072 :
1073 : /* Extract log format and log file path from the line. */
1074 24 : log_format = lbuffer;
1075 24 : log_filepath = strchr(lbuffer, ' ');
1076 24 : if (log_filepath == NULL)
1077 : {
1078 : /* Uh oh. No space found, so file content is corrupted. */
1079 0 : elog(ERROR,
1080 : "missing space character in \"%s\"", LOG_METAINFO_DATAFILE);
1081 : break;
1082 : }
1083 :
1084 24 : *log_filepath = '\0';
1085 24 : log_filepath++;
1086 24 : nlpos = strchr(log_filepath, '\n');
1087 24 : if (nlpos == NULL)
1088 : {
1089 : /* Uh oh. No newline found, so file content is corrupted. */
1090 0 : elog(ERROR,
1091 : "missing newline character in \"%s\"", LOG_METAINFO_DATAFILE);
1092 : break;
1093 : }
1094 24 : *nlpos = '\0';
1095 :
1096 24 : if (logfmt == NULL || strcmp(logfmt, log_format) == 0)
1097 : {
1098 12 : FreeFile(fd);
1099 12 : PG_RETURN_TEXT_P(cstring_to_text(log_filepath));
1100 : }
1101 : }
1102 :
1103 : /* Close the current log filename file. */
1104 0 : FreeFile(fd);
1105 :
1106 0 : PG_RETURN_NULL();
1107 : }
1108 :
1109 : /*
1110 : * Report current log file used by log collector (1 argument version)
1111 : *
1112 : * note: this wrapper is necessary to pass the sanity check in opr_sanity,
1113 : * which checks that all built-in functions that share the implementing C
1114 : * function take the same number of arguments
1115 : */
1116 : Datum
1117 12 : pg_current_logfile_1arg(PG_FUNCTION_ARGS)
1118 : {
1119 12 : return pg_current_logfile(fcinfo);
1120 : }
1121 :
1122 : /*
1123 : * SQL wrapper around RelationGetReplicaIndex().
1124 : */
1125 : Datum
1126 770 : pg_get_replica_identity_index(PG_FUNCTION_ARGS)
1127 : {
1128 770 : Oid reloid = PG_GETARG_OID(0);
1129 : Oid idxoid;
1130 : Relation rel;
1131 :
1132 770 : rel = table_open(reloid, AccessShareLock);
1133 770 : idxoid = RelationGetReplicaIndex(rel);
1134 770 : table_close(rel, AccessShareLock);
1135 :
1136 770 : if (OidIsValid(idxoid))
1137 408 : PG_RETURN_OID(idxoid);
1138 : else
1139 362 : PG_RETURN_NULL();
1140 : }
1141 :
1142 : /*
1143 : * Transition function for the ANY_VALUE aggregate
1144 : */
1145 : Datum
1146 18 : any_value_transfn(PG_FUNCTION_ARGS)
1147 : {
1148 18 : PG_RETURN_DATUM(PG_GETARG_DATUM(0));
1149 : }
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