Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * misc.c
4 : *
5 : *
6 : * Portions Copyright (c) 1996-2024, 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/sysattr.h"
25 : #include "access/table.h"
26 : #include "catalog/pg_tablespace.h"
27 : #include "catalog/pg_type.h"
28 : #include "catalog/system_fk_info.h"
29 : #include "commands/dbcommands.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 : /*
191 : * current_database()
192 : * Expose the current database to the user
193 : */
194 : Datum
195 5206 : current_database(PG_FUNCTION_ARGS)
196 : {
197 : Name db;
198 :
199 5206 : db = (Name) palloc(NAMEDATALEN);
200 :
201 5206 : namestrcpy(db, get_database_name(MyDatabaseId));
202 5206 : PG_RETURN_NAME(db);
203 : }
204 :
205 :
206 : /*
207 : * current_query()
208 : * Expose the current query to the user (useful in stored procedures)
209 : * We might want to use ActivePortal->sourceText someday.
210 : */
211 : Datum
212 0 : current_query(PG_FUNCTION_ARGS)
213 : {
214 : /* there is no easy way to access the more concise 'query_string' */
215 0 : if (debug_query_string)
216 0 : PG_RETURN_TEXT_P(cstring_to_text(debug_query_string));
217 : else
218 0 : PG_RETURN_NULL();
219 : }
220 :
221 : /* Function to find out which databases make use of a tablespace */
222 :
223 : Datum
224 6 : pg_tablespace_databases(PG_FUNCTION_ARGS)
225 : {
226 6 : Oid tablespaceOid = PG_GETARG_OID(0);
227 6 : ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
228 : char *location;
229 : DIR *dirdesc;
230 : struct dirent *de;
231 :
232 6 : InitMaterializedSRF(fcinfo, MAT_SRF_USE_EXPECTED_DESC);
233 :
234 6 : if (tablespaceOid == GLOBALTABLESPACE_OID)
235 : {
236 0 : ereport(WARNING,
237 : (errmsg("global tablespace never has databases")));
238 : /* return empty tuplestore */
239 0 : return (Datum) 0;
240 : }
241 :
242 6 : if (tablespaceOid == DEFAULTTABLESPACE_OID)
243 6 : location = "base";
244 : else
245 0 : location = psprintf("pg_tblspc/%u/%s", tablespaceOid,
246 : TABLESPACE_VERSION_DIRECTORY);
247 :
248 6 : dirdesc = AllocateDir(location);
249 :
250 6 : if (!dirdesc)
251 : {
252 : /* the only expected error is ENOENT */
253 0 : if (errno != ENOENT)
254 0 : ereport(ERROR,
255 : (errcode_for_file_access(),
256 : errmsg("could not open directory \"%s\": %m",
257 : location)));
258 0 : ereport(WARNING,
259 : (errmsg("%u is not a tablespace OID", tablespaceOid)));
260 : /* return empty tuplestore */
261 0 : return (Datum) 0;
262 : }
263 :
264 54 : while ((de = ReadDir(dirdesc, location)) != NULL)
265 : {
266 48 : Oid datOid = atooid(de->d_name);
267 : char *subdir;
268 : bool isempty;
269 : Datum values[1];
270 : bool nulls[1];
271 :
272 : /* this test skips . and .., but is awfully weak */
273 48 : if (!datOid)
274 18 : continue;
275 :
276 : /* if database subdir is empty, don't report tablespace as used */
277 :
278 30 : subdir = psprintf("%s/%s", location, de->d_name);
279 30 : isempty = directory_is_empty(subdir);
280 30 : pfree(subdir);
281 :
282 30 : if (isempty)
283 0 : continue; /* indeed, nothing in it */
284 :
285 30 : values[0] = ObjectIdGetDatum(datOid);
286 30 : nulls[0] = false;
287 :
288 30 : tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc,
289 : values, nulls);
290 : }
291 :
292 6 : FreeDir(dirdesc);
293 6 : return (Datum) 0;
294 : }
295 :
296 :
297 : /*
298 : * pg_tablespace_location - get location for a tablespace
299 : */
300 : Datum
301 124 : pg_tablespace_location(PG_FUNCTION_ARGS)
302 : {
303 124 : Oid tablespaceOid = PG_GETARG_OID(0);
304 : char sourcepath[MAXPGPATH];
305 : char targetpath[MAXPGPATH];
306 : int rllen;
307 : struct stat st;
308 :
309 : /*
310 : * It's useful to apply this function to pg_class.reltablespace, wherein
311 : * zero means "the database's default tablespace". So, rather than
312 : * throwing an error for zero, we choose to assume that's what is meant.
313 : */
314 124 : if (tablespaceOid == InvalidOid)
315 0 : tablespaceOid = MyDatabaseTableSpace;
316 :
317 : /*
318 : * Return empty string for the cluster's default tablespaces
319 : */
320 124 : if (tablespaceOid == DEFAULTTABLESPACE_OID ||
321 : tablespaceOid == GLOBALTABLESPACE_OID)
322 106 : PG_RETURN_TEXT_P(cstring_to_text(""));
323 :
324 : /*
325 : * Find the location of the tablespace by reading the symbolic link that
326 : * is in pg_tblspc/<oid>.
327 : */
328 18 : snprintf(sourcepath, sizeof(sourcepath), "pg_tblspc/%u", tablespaceOid);
329 :
330 : /*
331 : * Before reading the link, check if the source path is a link or a
332 : * junction point. Note that a directory is possible for a tablespace
333 : * created with allow_in_place_tablespaces enabled. If a directory is
334 : * found, a relative path to the data directory is returned.
335 : */
336 18 : if (lstat(sourcepath, &st) < 0)
337 : {
338 0 : ereport(ERROR,
339 : (errcode_for_file_access(),
340 : errmsg("could not stat file \"%s\": %m",
341 : sourcepath)));
342 : }
343 :
344 18 : if (!S_ISLNK(st.st_mode))
345 18 : PG_RETURN_TEXT_P(cstring_to_text(sourcepath));
346 :
347 : /*
348 : * In presence of a link or a junction point, return the path pointing to.
349 : */
350 0 : rllen = readlink(sourcepath, targetpath, sizeof(targetpath));
351 0 : if (rllen < 0)
352 0 : ereport(ERROR,
353 : (errcode_for_file_access(),
354 : errmsg("could not read symbolic link \"%s\": %m",
355 : sourcepath)));
356 0 : if (rllen >= sizeof(targetpath))
357 0 : ereport(ERROR,
358 : (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
359 : errmsg("symbolic link \"%s\" target is too long",
360 : sourcepath)));
361 0 : targetpath[rllen] = '\0';
362 :
363 0 : PG_RETURN_TEXT_P(cstring_to_text(targetpath));
364 : }
365 :
366 : /*
367 : * pg_sleep - delay for N seconds
368 : */
369 : Datum
370 76 : pg_sleep(PG_FUNCTION_ARGS)
371 : {
372 76 : float8 secs = PG_GETARG_FLOAT8(0);
373 : float8 endtime;
374 :
375 : /*
376 : * We sleep using WaitLatch, to ensure that we'll wake up promptly if an
377 : * important signal (such as SIGALRM or SIGINT) arrives. Because
378 : * WaitLatch's upper limit of delay is INT_MAX milliseconds, and the user
379 : * might ask for more than that, we sleep for at most 10 minutes and then
380 : * loop.
381 : *
382 : * By computing the intended stop time initially, we avoid accumulation of
383 : * extra delay across multiple sleeps. This also ensures we won't delay
384 : * less than the specified time when WaitLatch is terminated early by a
385 : * non-query-canceling signal such as SIGHUP.
386 : */
387 : #define GetNowFloat() ((float8) GetCurrentTimestamp() / 1000000.0)
388 :
389 76 : endtime = GetNowFloat() + secs;
390 :
391 : for (;;)
392 92 : {
393 : float8 delay;
394 : long delay_ms;
395 :
396 168 : CHECK_FOR_INTERRUPTS();
397 :
398 154 : delay = endtime - GetNowFloat();
399 154 : if (delay >= 600.0)
400 0 : delay_ms = 600000;
401 154 : else if (delay > 0.0)
402 92 : delay_ms = (long) ceil(delay * 1000.0);
403 : else
404 62 : break;
405 :
406 92 : (void) WaitLatch(MyLatch,
407 : WL_LATCH_SET | WL_TIMEOUT | WL_EXIT_ON_PM_DEATH,
408 : delay_ms,
409 : WAIT_EVENT_PG_SLEEP);
410 92 : ResetLatch(MyLatch);
411 : }
412 :
413 62 : PG_RETURN_VOID();
414 : }
415 :
416 : /* Function to return the list of grammar keywords */
417 : Datum
418 0 : pg_get_keywords(PG_FUNCTION_ARGS)
419 : {
420 : FuncCallContext *funcctx;
421 :
422 0 : if (SRF_IS_FIRSTCALL())
423 : {
424 : MemoryContext oldcontext;
425 : TupleDesc tupdesc;
426 :
427 0 : funcctx = SRF_FIRSTCALL_INIT();
428 0 : oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
429 :
430 0 : if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
431 0 : elog(ERROR, "return type must be a row type");
432 0 : funcctx->tuple_desc = tupdesc;
433 0 : funcctx->attinmeta = TupleDescGetAttInMetadata(tupdesc);
434 :
435 0 : MemoryContextSwitchTo(oldcontext);
436 : }
437 :
438 0 : funcctx = SRF_PERCALL_SETUP();
439 :
440 0 : if (funcctx->call_cntr < ScanKeywords.num_keywords)
441 : {
442 : char *values[5];
443 : HeapTuple tuple;
444 :
445 : /* cast-away-const is ugly but alternatives aren't much better */
446 0 : values[0] = unconstify(char *,
447 : GetScanKeyword(funcctx->call_cntr,
448 : &ScanKeywords));
449 :
450 0 : switch (ScanKeywordCategories[funcctx->call_cntr])
451 : {
452 0 : case UNRESERVED_KEYWORD:
453 0 : values[1] = "U";
454 0 : values[3] = _("unreserved");
455 0 : break;
456 0 : case COL_NAME_KEYWORD:
457 0 : values[1] = "C";
458 0 : values[3] = _("unreserved (cannot be function or type name)");
459 0 : break;
460 0 : case TYPE_FUNC_NAME_KEYWORD:
461 0 : values[1] = "T";
462 0 : values[3] = _("reserved (can be function or type name)");
463 0 : break;
464 0 : case RESERVED_KEYWORD:
465 0 : values[1] = "R";
466 0 : values[3] = _("reserved");
467 0 : break;
468 0 : default: /* shouldn't be possible */
469 0 : values[1] = NULL;
470 0 : values[3] = NULL;
471 0 : break;
472 : }
473 :
474 0 : if (ScanKeywordBareLabel[funcctx->call_cntr])
475 : {
476 0 : values[2] = "true";
477 0 : values[4] = _("can be bare label");
478 : }
479 : else
480 : {
481 0 : values[2] = "false";
482 0 : values[4] = _("requires AS");
483 : }
484 :
485 0 : tuple = BuildTupleFromCStrings(funcctx->attinmeta, values);
486 :
487 0 : SRF_RETURN_NEXT(funcctx, HeapTupleGetDatum(tuple));
488 : }
489 :
490 0 : SRF_RETURN_DONE(funcctx);
491 : }
492 :
493 :
494 : /* Function to return the list of catalog foreign key relationships */
495 : Datum
496 1320 : pg_get_catalog_foreign_keys(PG_FUNCTION_ARGS)
497 : {
498 : FuncCallContext *funcctx;
499 : FmgrInfo *arrayinp;
500 :
501 1320 : if (SRF_IS_FIRSTCALL())
502 : {
503 : MemoryContext oldcontext;
504 : TupleDesc tupdesc;
505 :
506 6 : funcctx = SRF_FIRSTCALL_INIT();
507 6 : oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
508 :
509 6 : if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
510 0 : elog(ERROR, "return type must be a row type");
511 6 : funcctx->tuple_desc = BlessTupleDesc(tupdesc);
512 :
513 : /*
514 : * We use array_in to convert the C strings in sys_fk_relationships[]
515 : * to text arrays. But we cannot use DirectFunctionCallN to call
516 : * array_in, and it wouldn't be very efficient if we could. Fill an
517 : * FmgrInfo to use for the call.
518 : */
519 6 : arrayinp = (FmgrInfo *) palloc(sizeof(FmgrInfo));
520 6 : fmgr_info(F_ARRAY_IN, arrayinp);
521 6 : funcctx->user_fctx = arrayinp;
522 :
523 6 : MemoryContextSwitchTo(oldcontext);
524 : }
525 :
526 1320 : funcctx = SRF_PERCALL_SETUP();
527 1320 : arrayinp = (FmgrInfo *) funcctx->user_fctx;
528 :
529 1320 : if (funcctx->call_cntr < lengthof(sys_fk_relationships))
530 : {
531 1314 : const SysFKRelationship *fkrel = &sys_fk_relationships[funcctx->call_cntr];
532 : Datum values[6];
533 : bool nulls[6];
534 : HeapTuple tuple;
535 :
536 1314 : memset(nulls, false, sizeof(nulls));
537 :
538 1314 : values[0] = ObjectIdGetDatum(fkrel->fk_table);
539 1314 : values[1] = FunctionCall3(arrayinp,
540 : CStringGetDatum(fkrel->fk_columns),
541 : ObjectIdGetDatum(TEXTOID),
542 : Int32GetDatum(-1));
543 1314 : values[2] = ObjectIdGetDatum(fkrel->pk_table);
544 1314 : values[3] = FunctionCall3(arrayinp,
545 : CStringGetDatum(fkrel->pk_columns),
546 : ObjectIdGetDatum(TEXTOID),
547 : Int32GetDatum(-1));
548 1314 : values[4] = BoolGetDatum(fkrel->is_array);
549 1314 : values[5] = BoolGetDatum(fkrel->is_opt);
550 :
551 1314 : tuple = heap_form_tuple(funcctx->tuple_desc, values, nulls);
552 :
553 1314 : SRF_RETURN_NEXT(funcctx, HeapTupleGetDatum(tuple));
554 : }
555 :
556 6 : SRF_RETURN_DONE(funcctx);
557 : }
558 :
559 :
560 : /*
561 : * Return the type of the argument.
562 : */
563 : Datum
564 1562 : pg_typeof(PG_FUNCTION_ARGS)
565 : {
566 1562 : PG_RETURN_OID(get_fn_expr_argtype(fcinfo->flinfo, 0));
567 : }
568 :
569 :
570 : /*
571 : * Return the base type of the argument.
572 : * If the given type is a domain, return its base type;
573 : * otherwise return the type's own OID.
574 : * Return NULL if the type OID doesn't exist or points to a
575 : * non-existent base type.
576 : *
577 : * This is a SQL-callable version of getBaseType(). Unlike that function,
578 : * we don't want to fail for a bogus type OID; this is helpful to keep race
579 : * conditions from turning into query failures when scanning the catalogs.
580 : * Hence we need our own implementation.
581 : */
582 : Datum
583 18 : pg_basetype(PG_FUNCTION_ARGS)
584 : {
585 18 : Oid typid = PG_GETARG_OID(0);
586 :
587 : /*
588 : * We loop to find the bottom base type in a stack of domains.
589 : */
590 : for (;;)
591 18 : {
592 : HeapTuple tup;
593 : Form_pg_type typTup;
594 :
595 36 : tup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(typid));
596 36 : if (!HeapTupleIsValid(tup))
597 6 : PG_RETURN_NULL(); /* return NULL for bogus OID */
598 30 : typTup = (Form_pg_type) GETSTRUCT(tup);
599 30 : if (typTup->typtype != TYPTYPE_DOMAIN)
600 : {
601 : /* Not a domain, so done */
602 12 : ReleaseSysCache(tup);
603 12 : break;
604 : }
605 :
606 18 : typid = typTup->typbasetype;
607 18 : ReleaseSysCache(tup);
608 : }
609 :
610 12 : PG_RETURN_OID(typid);
611 : }
612 :
613 :
614 : /*
615 : * Implementation of the COLLATE FOR expression; returns the collation
616 : * of the argument.
617 : */
618 : Datum
619 30 : pg_collation_for(PG_FUNCTION_ARGS)
620 : {
621 : Oid typeid;
622 : Oid collid;
623 :
624 30 : typeid = get_fn_expr_argtype(fcinfo->flinfo, 0);
625 30 : if (!typeid)
626 0 : PG_RETURN_NULL();
627 30 : if (!type_is_collatable(typeid) && typeid != UNKNOWNOID)
628 6 : ereport(ERROR,
629 : (errcode(ERRCODE_DATATYPE_MISMATCH),
630 : errmsg("collations are not supported by type %s",
631 : format_type_be(typeid))));
632 :
633 24 : collid = PG_GET_COLLATION();
634 24 : if (!collid)
635 6 : PG_RETURN_NULL();
636 18 : PG_RETURN_TEXT_P(cstring_to_text(generate_collation_name(collid)));
637 : }
638 :
639 :
640 : /*
641 : * pg_relation_is_updatable - determine which update events the specified
642 : * relation supports.
643 : *
644 : * This relies on relation_is_updatable() in rewriteHandler.c, which see
645 : * for additional information.
646 : */
647 : Datum
648 894 : pg_relation_is_updatable(PG_FUNCTION_ARGS)
649 : {
650 894 : Oid reloid = PG_GETARG_OID(0);
651 894 : bool include_triggers = PG_GETARG_BOOL(1);
652 :
653 894 : PG_RETURN_INT32(relation_is_updatable(reloid, NIL, include_triggers, NULL));
654 : }
655 :
656 : /*
657 : * pg_column_is_updatable - determine whether a column is updatable
658 : *
659 : * This function encapsulates the decision about just what
660 : * information_schema.columns.is_updatable actually means. It's not clear
661 : * whether deletability of the column's relation should be required, so
662 : * we want that decision in C code where we could change it without initdb.
663 : */
664 : Datum
665 570 : pg_column_is_updatable(PG_FUNCTION_ARGS)
666 : {
667 570 : Oid reloid = PG_GETARG_OID(0);
668 570 : AttrNumber attnum = PG_GETARG_INT16(1);
669 570 : AttrNumber col = attnum - FirstLowInvalidHeapAttributeNumber;
670 570 : bool include_triggers = PG_GETARG_BOOL(2);
671 : int events;
672 :
673 : /* System columns are never updatable */
674 570 : if (attnum <= 0)
675 0 : PG_RETURN_BOOL(false);
676 :
677 570 : events = relation_is_updatable(reloid, NIL, include_triggers,
678 : bms_make_singleton(col));
679 :
680 : /* We require both updatability and deletability of the relation */
681 : #define REQ_EVENTS ((1 << CMD_UPDATE) | (1 << CMD_DELETE))
682 :
683 570 : PG_RETURN_BOOL((events & REQ_EVENTS) == REQ_EVENTS);
684 : }
685 :
686 :
687 : /*
688 : * pg_input_is_valid - test whether string is valid input for datatype.
689 : *
690 : * Returns true if OK, false if not.
691 : *
692 : * This will only work usefully if the datatype's input function has been
693 : * updated to return "soft" errors via errsave/ereturn.
694 : */
695 : Datum
696 884 : pg_input_is_valid(PG_FUNCTION_ARGS)
697 : {
698 884 : text *txt = PG_GETARG_TEXT_PP(0);
699 884 : text *typname = PG_GETARG_TEXT_PP(1);
700 884 : ErrorSaveContext escontext = {T_ErrorSaveContext};
701 :
702 884 : PG_RETURN_BOOL(pg_input_is_valid_common(fcinfo, txt, typname,
703 : &escontext));
704 : }
705 :
706 : /*
707 : * pg_input_error_info - test whether string is valid input for datatype.
708 : *
709 : * Returns NULL if OK, else the primary message, detail message, hint message
710 : * and sql error code from the error.
711 : *
712 : * This will only work usefully if the datatype's input function has been
713 : * updated to return "soft" errors via errsave/ereturn.
714 : */
715 : Datum
716 766 : pg_input_error_info(PG_FUNCTION_ARGS)
717 : {
718 766 : text *txt = PG_GETARG_TEXT_PP(0);
719 766 : text *typname = PG_GETARG_TEXT_PP(1);
720 766 : ErrorSaveContext escontext = {T_ErrorSaveContext};
721 : TupleDesc tupdesc;
722 : Datum values[4];
723 : bool isnull[4];
724 :
725 766 : if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
726 0 : elog(ERROR, "return type must be a row type");
727 :
728 : /* Enable details_wanted */
729 766 : escontext.details_wanted = true;
730 :
731 766 : if (pg_input_is_valid_common(fcinfo, txt, typname,
732 : &escontext))
733 26 : memset(isnull, true, sizeof(isnull));
734 : else
735 : {
736 : char *sqlstate;
737 :
738 : Assert(escontext.error_occurred);
739 : Assert(escontext.error_data != NULL);
740 : Assert(escontext.error_data->message != NULL);
741 :
742 710 : memset(isnull, false, sizeof(isnull));
743 :
744 710 : values[0] = CStringGetTextDatum(escontext.error_data->message);
745 :
746 710 : if (escontext.error_data->detail != NULL)
747 62 : values[1] = CStringGetTextDatum(escontext.error_data->detail);
748 : else
749 648 : isnull[1] = true;
750 :
751 710 : if (escontext.error_data->hint != NULL)
752 0 : values[2] = CStringGetTextDatum(escontext.error_data->hint);
753 : else
754 710 : isnull[2] = true;
755 :
756 710 : sqlstate = unpack_sql_state(escontext.error_data->sqlerrcode);
757 710 : values[3] = CStringGetTextDatum(sqlstate);
758 : }
759 :
760 736 : return HeapTupleGetDatum(heap_form_tuple(tupdesc, values, isnull));
761 : }
762 :
763 : /* Common subroutine for the above */
764 : static bool
765 1650 : pg_input_is_valid_common(FunctionCallInfo fcinfo,
766 : text *txt, text *typname,
767 : ErrorSaveContext *escontext)
768 : {
769 1650 : char *str = text_to_cstring(txt);
770 : ValidIOData *my_extra;
771 : Datum converted;
772 :
773 : /*
774 : * We arrange to look up the needed I/O info just once per series of
775 : * calls, assuming the data type doesn't change underneath us.
776 : */
777 1650 : my_extra = (ValidIOData *) fcinfo->flinfo->fn_extra;
778 1650 : if (my_extra == NULL)
779 : {
780 3076 : fcinfo->flinfo->fn_extra =
781 1538 : MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
782 : sizeof(ValidIOData));
783 1538 : my_extra = (ValidIOData *) fcinfo->flinfo->fn_extra;
784 1538 : my_extra->typoid = InvalidOid;
785 : /* Detect whether typname argument is constant. */
786 1538 : my_extra->typname_constant = get_fn_expr_arg_stable(fcinfo->flinfo, 1);
787 : }
788 :
789 : /*
790 : * If the typname argument is constant, we only need to parse it the first
791 : * time through.
792 : */
793 1650 : if (my_extra->typoid == InvalidOid || !my_extra->typname_constant)
794 : {
795 1574 : char *typnamestr = text_to_cstring(typname);
796 : Oid typoid;
797 :
798 : /* Parse type-name argument to obtain type OID and encoded typmod. */
799 1574 : (void) parseTypeString(typnamestr, &typoid, &my_extra->typmod, NULL);
800 :
801 : /* Update type-specific info if typoid changed. */
802 1574 : if (my_extra->typoid != typoid)
803 : {
804 1554 : getTypeInputInfo(typoid,
805 : &my_extra->typiofunc,
806 : &my_extra->typioparam);
807 1554 : fmgr_info_cxt(my_extra->typiofunc, &my_extra->inputproc,
808 1554 : fcinfo->flinfo->fn_mcxt);
809 1554 : my_extra->typoid = typoid;
810 : }
811 : }
812 :
813 : /* Now we can try to perform the conversion. */
814 1650 : return InputFunctionCallSafe(&my_extra->inputproc,
815 : str,
816 : my_extra->typioparam,
817 : my_extra->typmod,
818 : (Node *) escontext,
819 : &converted);
820 : }
821 :
822 :
823 : /*
824 : * Is character a valid identifier start?
825 : * Must match scan.l's {ident_start} character class.
826 : */
827 : static bool
828 2202 : is_ident_start(unsigned char c)
829 : {
830 : /* Underscores and ASCII letters are OK */
831 2202 : if (c == '_')
832 0 : return true;
833 2202 : if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z'))
834 2052 : return true;
835 : /* Any high-bit-set character is OK (might be part of a multibyte char) */
836 150 : if (IS_HIGHBIT_SET(c))
837 0 : return true;
838 150 : return false;
839 : }
840 :
841 : /*
842 : * Is character a valid identifier continuation?
843 : * Must match scan.l's {ident_cont} character class.
844 : */
845 : static bool
846 2052 : is_ident_cont(unsigned char c)
847 : {
848 : /* Can be digit or dollar sign ... */
849 2052 : if ((c >= '0' && c <= '9') || c == '$')
850 0 : return true;
851 : /* ... or an identifier start character */
852 2052 : return is_ident_start(c);
853 : }
854 :
855 : /*
856 : * parse_ident - parse a SQL qualified identifier into separate identifiers.
857 : * When strict mode is active (second parameter), then any chars after
858 : * the last identifier are disallowed.
859 : */
860 : Datum
861 114 : parse_ident(PG_FUNCTION_ARGS)
862 : {
863 114 : text *qualname = PG_GETARG_TEXT_PP(0);
864 114 : bool strict = PG_GETARG_BOOL(1);
865 114 : char *qualname_str = text_to_cstring(qualname);
866 114 : ArrayBuildState *astate = NULL;
867 : char *nextp;
868 114 : bool after_dot = false;
869 :
870 : /*
871 : * The code below scribbles on qualname_str in some cases, so we should
872 : * reconvert qualname if we need to show the original string in error
873 : * messages.
874 : */
875 114 : nextp = qualname_str;
876 :
877 : /* skip leading whitespace */
878 144 : while (scanner_isspace(*nextp))
879 30 : nextp++;
880 :
881 : for (;;)
882 96 : {
883 : char *curname;
884 210 : bool missing_ident = true;
885 :
886 210 : if (*nextp == '"')
887 : {
888 : char *endp;
889 :
890 60 : curname = nextp + 1;
891 : for (;;)
892 : {
893 60 : endp = strchr(nextp + 1, '"');
894 60 : if (endp == NULL)
895 0 : ereport(ERROR,
896 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
897 : errmsg("string is not a valid identifier: \"%s\"",
898 : text_to_cstring(qualname)),
899 : errdetail("String has unclosed double quotes.")));
900 60 : if (endp[1] != '"')
901 60 : break;
902 0 : memmove(endp, endp + 1, strlen(endp));
903 0 : nextp = endp;
904 : }
905 60 : nextp = endp + 1;
906 60 : *endp = '\0';
907 :
908 60 : if (endp - curname == 0)
909 0 : ereport(ERROR,
910 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
911 : errmsg("string is not a valid identifier: \"%s\"",
912 : text_to_cstring(qualname)),
913 : errdetail("Quoted identifier must not be empty.")));
914 :
915 60 : astate = accumArrayResult(astate, CStringGetTextDatum(curname),
916 : false, TEXTOID, CurrentMemoryContext);
917 60 : missing_ident = false;
918 : }
919 150 : else if (is_ident_start((unsigned char) *nextp))
920 : {
921 : char *downname;
922 : int len;
923 : text *part;
924 :
925 102 : curname = nextp++;
926 2052 : while (is_ident_cont((unsigned char) *nextp))
927 1950 : nextp++;
928 :
929 102 : len = nextp - curname;
930 :
931 : /*
932 : * We don't implicitly truncate identifiers. This is useful for
933 : * allowing the user to check for specific parts of the identifier
934 : * being too long. It's easy enough for the user to get the
935 : * truncated names by casting our output to name[].
936 : */
937 102 : downname = downcase_identifier(curname, len, false, false);
938 102 : part = cstring_to_text_with_len(downname, len);
939 102 : astate = accumArrayResult(astate, PointerGetDatum(part), false,
940 : TEXTOID, CurrentMemoryContext);
941 102 : missing_ident = false;
942 : }
943 :
944 210 : if (missing_ident)
945 : {
946 : /* Different error messages based on where we failed. */
947 48 : if (*nextp == '.')
948 18 : ereport(ERROR,
949 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
950 : errmsg("string is not a valid identifier: \"%s\"",
951 : text_to_cstring(qualname)),
952 : errdetail("No valid identifier before \".\".")));
953 30 : else if (after_dot)
954 12 : ereport(ERROR,
955 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
956 : errmsg("string is not a valid identifier: \"%s\"",
957 : text_to_cstring(qualname)),
958 : errdetail("No valid identifier after \".\".")));
959 : else
960 18 : ereport(ERROR,
961 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
962 : errmsg("string is not a valid identifier: \"%s\"",
963 : text_to_cstring(qualname))));
964 : }
965 :
966 204 : while (scanner_isspace(*nextp))
967 42 : nextp++;
968 :
969 162 : if (*nextp == '.')
970 : {
971 96 : after_dot = true;
972 96 : nextp++;
973 126 : while (scanner_isspace(*nextp))
974 30 : nextp++;
975 : }
976 66 : else if (*nextp == '\0')
977 : {
978 36 : break;
979 : }
980 : else
981 : {
982 30 : if (strict)
983 24 : ereport(ERROR,
984 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
985 : errmsg("string is not a valid identifier: \"%s\"",
986 : text_to_cstring(qualname))));
987 6 : break;
988 : }
989 : }
990 :
991 42 : PG_RETURN_DATUM(makeArrayResult(astate, CurrentMemoryContext));
992 : }
993 :
994 : /*
995 : * pg_current_logfile
996 : *
997 : * Report current log file used by log collector by scanning current_logfiles.
998 : */
999 : Datum
1000 12 : pg_current_logfile(PG_FUNCTION_ARGS)
1001 : {
1002 : FILE *fd;
1003 : char lbuffer[MAXPGPATH];
1004 : char *logfmt;
1005 :
1006 : /* The log format parameter is optional */
1007 12 : if (PG_NARGS() == 0 || PG_ARGISNULL(0))
1008 0 : logfmt = NULL;
1009 : else
1010 : {
1011 12 : logfmt = text_to_cstring(PG_GETARG_TEXT_PP(0));
1012 :
1013 12 : if (strcmp(logfmt, "stderr") != 0 &&
1014 8 : strcmp(logfmt, "csvlog") != 0 &&
1015 4 : strcmp(logfmt, "jsonlog") != 0)
1016 0 : ereport(ERROR,
1017 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
1018 : errmsg("log format \"%s\" is not supported", logfmt),
1019 : errhint("The supported log formats are \"stderr\", \"csvlog\", and \"jsonlog\".")));
1020 : }
1021 :
1022 12 : fd = AllocateFile(LOG_METAINFO_DATAFILE, "r");
1023 12 : if (fd == NULL)
1024 : {
1025 0 : if (errno != ENOENT)
1026 0 : ereport(ERROR,
1027 : (errcode_for_file_access(),
1028 : errmsg("could not read file \"%s\": %m",
1029 : LOG_METAINFO_DATAFILE)));
1030 0 : PG_RETURN_NULL();
1031 : }
1032 :
1033 : #ifdef WIN32
1034 : /* syslogger.c writes CRLF line endings on Windows */
1035 : _setmode(_fileno(fd), _O_TEXT);
1036 : #endif
1037 :
1038 : /*
1039 : * Read the file to gather current log filename(s) registered by the
1040 : * syslogger.
1041 : */
1042 24 : while (fgets(lbuffer, sizeof(lbuffer), fd) != NULL)
1043 : {
1044 : char *log_format;
1045 : char *log_filepath;
1046 : char *nlpos;
1047 :
1048 : /* Extract log format and log file path from the line. */
1049 24 : log_format = lbuffer;
1050 24 : log_filepath = strchr(lbuffer, ' ');
1051 24 : if (log_filepath == NULL)
1052 : {
1053 : /* Uh oh. No space found, so file content is corrupted. */
1054 0 : elog(ERROR,
1055 : "missing space character in \"%s\"", LOG_METAINFO_DATAFILE);
1056 : break;
1057 : }
1058 :
1059 24 : *log_filepath = '\0';
1060 24 : log_filepath++;
1061 24 : nlpos = strchr(log_filepath, '\n');
1062 24 : if (nlpos == NULL)
1063 : {
1064 : /* Uh oh. No newline found, so file content is corrupted. */
1065 0 : elog(ERROR,
1066 : "missing newline character in \"%s\"", LOG_METAINFO_DATAFILE);
1067 : break;
1068 : }
1069 24 : *nlpos = '\0';
1070 :
1071 24 : if (logfmt == NULL || strcmp(logfmt, log_format) == 0)
1072 : {
1073 12 : FreeFile(fd);
1074 12 : PG_RETURN_TEXT_P(cstring_to_text(log_filepath));
1075 : }
1076 : }
1077 :
1078 : /* Close the current log filename file. */
1079 0 : FreeFile(fd);
1080 :
1081 0 : PG_RETURN_NULL();
1082 : }
1083 :
1084 : /*
1085 : * Report current log file used by log collector (1 argument version)
1086 : *
1087 : * note: this wrapper is necessary to pass the sanity check in opr_sanity,
1088 : * which checks that all built-in functions that share the implementing C
1089 : * function take the same number of arguments
1090 : */
1091 : Datum
1092 12 : pg_current_logfile_1arg(PG_FUNCTION_ARGS)
1093 : {
1094 12 : return pg_current_logfile(fcinfo);
1095 : }
1096 :
1097 : /*
1098 : * SQL wrapper around RelationGetReplicaIndex().
1099 : */
1100 : Datum
1101 678 : pg_get_replica_identity_index(PG_FUNCTION_ARGS)
1102 : {
1103 678 : Oid reloid = PG_GETARG_OID(0);
1104 : Oid idxoid;
1105 : Relation rel;
1106 :
1107 678 : rel = table_open(reloid, AccessShareLock);
1108 678 : idxoid = RelationGetReplicaIndex(rel);
1109 678 : table_close(rel, AccessShareLock);
1110 :
1111 678 : if (OidIsValid(idxoid))
1112 388 : PG_RETURN_OID(idxoid);
1113 : else
1114 290 : PG_RETURN_NULL();
1115 : }
1116 :
1117 : /*
1118 : * Transition function for the ANY_VALUE aggregate
1119 : */
1120 : Datum
1121 18 : any_value_transfn(PG_FUNCTION_ARGS)
1122 : {
1123 18 : PG_RETURN_DATUM(PG_GETARG_DATUM(0));
1124 : }
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