Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * String-processing utility routines for frontend code
4 : *
5 : * Assorted utility functions that are useful in constructing SQL queries
6 : * and interpreting backend output.
7 : *
8 : *
9 : * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
10 : * Portions Copyright (c) 1994, Regents of the University of California
11 : *
12 : * src/fe_utils/string_utils.c
13 : *
14 : *-------------------------------------------------------------------------
15 : */
16 : #include "postgres_fe.h"
17 :
18 : #include <ctype.h>
19 :
20 : #include "common/keywords.h"
21 : #include "fe_utils/string_utils.h"
22 : #include "mb/pg_wchar.h"
23 :
24 : static PQExpBuffer defaultGetLocalPQExpBuffer(void);
25 :
26 : /* Globals exported by this file */
27 : int quote_all_identifiers = 0;
28 : PQExpBuffer (*getLocalPQExpBuffer) (void) = defaultGetLocalPQExpBuffer;
29 :
30 : static int fmtIdEncoding = -1;
31 :
32 :
33 : /*
34 : * Returns a temporary PQExpBuffer, valid until the next call to the function.
35 : * This is used by fmtId and fmtQualifiedId.
36 : *
37 : * Non-reentrant and non-thread-safe but reduces memory leakage. You can
38 : * replace this with a custom version by setting the getLocalPQExpBuffer
39 : * function pointer.
40 : */
41 : static PQExpBuffer
42 671686 : defaultGetLocalPQExpBuffer(void)
43 : {
44 : static PQExpBuffer id_return = NULL;
45 :
46 671686 : if (id_return) /* first time through? */
47 : {
48 : /* same buffer, just wipe contents */
49 670930 : resetPQExpBuffer(id_return);
50 : }
51 : else
52 : {
53 : /* new buffer */
54 756 : id_return = createPQExpBuffer();
55 : }
56 :
57 671686 : return id_return;
58 : }
59 :
60 : /*
61 : * Set the encoding that fmtId() and fmtQualifiedId() use.
62 : *
63 : * This is not safe against multiple connections having different encodings,
64 : * but there is no real other way to address the need to know the encoding for
65 : * fmtId()/fmtQualifiedId() input for safe escaping. Eventually we should get
66 : * rid of fmtId().
67 : */
68 : void
69 19872 : setFmtEncoding(int encoding)
70 : {
71 19872 : fmtIdEncoding = encoding;
72 19872 : }
73 :
74 : /*
75 : * Return the currently configured encoding for fmtId() and fmtQualifiedId().
76 : */
77 : static int
78 462030 : getFmtEncoding(void)
79 : {
80 462030 : if (fmtIdEncoding != -1)
81 462030 : return fmtIdEncoding;
82 :
83 : /*
84 : * In assertion builds it seems best to fail hard if the encoding was not
85 : * set, to make it easier to find places with missing calls. But in
86 : * production builds that seems like a bad idea, thus we instead just
87 : * default to UTF-8.
88 : */
89 : Assert(fmtIdEncoding != -1);
90 :
91 0 : return PG_UTF8;
92 : }
93 :
94 : /*
95 : * Quotes input string if it's not a legitimate SQL identifier as-is.
96 : *
97 : * Note that the returned string must be used before calling fmtIdEnc again,
98 : * since we re-use the same return buffer each time.
99 : */
100 : const char *
101 570406 : fmtIdEnc(const char *rawid, int encoding)
102 : {
103 570406 : PQExpBuffer id_return = getLocalPQExpBuffer();
104 :
105 : const char *cp;
106 570406 : bool need_quotes = false;
107 570406 : size_t remaining = strlen(rawid);
108 :
109 : /*
110 : * These checks need to match the identifier production in scan.l. Don't
111 : * use islower() etc.
112 : */
113 570406 : if (quote_all_identifiers)
114 35050 : need_quotes = true;
115 : /* slightly different rules for first character */
116 535356 : else if (!((rawid[0] >= 'a' && rawid[0] <= 'z') || rawid[0] == '_'))
117 1286 : need_quotes = true;
118 : else
119 : {
120 : /* otherwise check the entire string */
121 534070 : cp = rawid;
122 5850366 : for (size_t i = 0; i < remaining; i++, cp++)
123 : {
124 5335736 : if (!((*cp >= 'a' && *cp <= 'z')
125 720572 : || (*cp >= '0' && *cp <= '9')
126 491556 : || (*cp == '_')))
127 : {
128 19440 : need_quotes = true;
129 19440 : break;
130 : }
131 : }
132 : }
133 :
134 570406 : if (!need_quotes)
135 : {
136 : /*
137 : * Check for keyword. We quote keywords except for unreserved ones.
138 : * (In some cases we could avoid quoting a col_name or type_func_name
139 : * keyword, but it seems much harder than it's worth to tell that.)
140 : *
141 : * Note: ScanKeywordLookup() does case-insensitive comparison, but
142 : * that's fine, since we already know we have all-lower-case.
143 : */
144 514630 : int kwnum = ScanKeywordLookup(rawid, &ScanKeywords);
145 :
146 514630 : if (kwnum >= 0 && ScanKeywordCategories[kwnum] != UNRESERVED_KEYWORD)
147 1440 : need_quotes = true;
148 : }
149 :
150 570406 : if (!need_quotes)
151 : {
152 : /* no quoting needed */
153 513190 : appendPQExpBufferStr(id_return, rawid);
154 : }
155 : else
156 : {
157 57216 : appendPQExpBufferChar(id_return, '"');
158 :
159 57216 : cp = &rawid[0];
160 635010 : while (remaining > 0)
161 : {
162 : int charlen;
163 :
164 : /* Fast path for plain ASCII */
165 577794 : if (!IS_HIGHBIT_SET(*cp))
166 : {
167 : /*
168 : * Did we find a double-quote in the string? Then make this a
169 : * double double-quote per SQL99. Before, we put in a
170 : * backslash/double-quote pair. - thomas 2000-08-05
171 : */
172 572320 : if (*cp == '"')
173 420 : appendPQExpBufferChar(id_return, '"');
174 572320 : appendPQExpBufferChar(id_return, *cp);
175 572320 : remaining--;
176 572320 : cp++;
177 572320 : continue;
178 : }
179 :
180 : /* Slow path for possible multibyte characters */
181 5474 : charlen = pg_encoding_mblen(encoding, cp);
182 :
183 10904 : if (remaining < charlen ||
184 5430 : pg_encoding_verifymbchar(encoding, cp, charlen) == -1)
185 : {
186 : /*
187 : * Multibyte character is invalid. It's important to verify
188 : * that as invalid multibyte characters could e.g. be used to
189 : * "skip" over quote characters, e.g. when parsing
190 : * character-by-character.
191 : *
192 : * Replace the character's first byte with an invalid
193 : * sequence. The invalid sequence ensures that the escaped
194 : * string will trigger an error on the server-side, even if we
195 : * can't directly report an error here.
196 : *
197 : * It would be a bit faster to verify the whole string the
198 : * first time we encounter a set highbit, but this way we can
199 : * replace just the invalid data, which probably makes it
200 : * easier for users to find the invalidly encoded portion of a
201 : * larger string.
202 : */
203 70 : if (enlargePQExpBuffer(id_return, 2))
204 : {
205 70 : pg_encoding_set_invalid(encoding,
206 70 : id_return->data + id_return->len);
207 70 : id_return->len += 2;
208 70 : id_return->data[id_return->len] = '\0';
209 : }
210 :
211 : /*
212 : * Handle the following bytes as if this byte didn't exist.
213 : * That's safer in case the subsequent bytes contain
214 : * characters that are significant for the caller (e.g. '>' in
215 : * html).
216 : */
217 70 : remaining--;
218 70 : cp++;
219 : }
220 : else
221 : {
222 10834 : for (int i = 0; i < charlen; i++)
223 : {
224 5430 : appendPQExpBufferChar(id_return, *cp);
225 5430 : remaining--;
226 5430 : cp++;
227 : }
228 : }
229 : }
230 :
231 57216 : appendPQExpBufferChar(id_return, '"');
232 : }
233 :
234 570406 : return id_return->data;
235 : }
236 :
237 : /*
238 : * Quotes input string if it's not a legitimate SQL identifier as-is.
239 : *
240 : * Note that the returned string must be used before calling fmtId again,
241 : * since we re-use the same return buffer each time.
242 : *
243 : * NB: This assumes setFmtEncoding() previously has been called to configure
244 : * the encoding of rawid. It is preferable to use fmtIdEnc() with an
245 : * explicit encoding.
246 : */
247 : const char *
248 367700 : fmtId(const char *rawid)
249 : {
250 367700 : return fmtIdEnc(rawid, getFmtEncoding());
251 : }
252 :
253 : /*
254 : * fmtQualifiedIdEnc - construct a schema-qualified name, with quoting as
255 : * needed.
256 : *
257 : * Like fmtId, use the result before calling again.
258 : *
259 : * Since we call fmtId and it also uses getLocalPQExpBuffer() we cannot
260 : * use that buffer until we're finished with calling fmtId().
261 : */
262 : const char *
263 101280 : fmtQualifiedIdEnc(const char *schema, const char *id, int encoding)
264 : {
265 : PQExpBuffer id_return;
266 101280 : PQExpBuffer lcl_pqexp = createPQExpBuffer();
267 :
268 : /* Some callers might fail to provide a schema name */
269 101280 : if (schema && *schema)
270 : {
271 101280 : appendPQExpBuffer(lcl_pqexp, "%s.", fmtIdEnc(schema, encoding));
272 : }
273 101280 : appendPQExpBufferStr(lcl_pqexp, fmtIdEnc(id, encoding));
274 :
275 101280 : id_return = getLocalPQExpBuffer();
276 :
277 101280 : appendPQExpBufferStr(id_return, lcl_pqexp->data);
278 101280 : destroyPQExpBuffer(lcl_pqexp);
279 :
280 101280 : return id_return->data;
281 : }
282 :
283 : /*
284 : * fmtQualifiedId - construct a schema-qualified name, with quoting as needed.
285 : *
286 : * Like fmtId, use the result before calling again.
287 : *
288 : * Since we call fmtId and it also uses getLocalPQExpBuffer() we cannot
289 : * use that buffer until we're finished with calling fmtId().
290 : *
291 : * NB: This assumes setFmtEncoding() previously has been called to configure
292 : * the encoding of schema/id. It is preferable to use fmtQualifiedIdEnc()
293 : * with an explicit encoding.
294 : */
295 : const char *
296 94330 : fmtQualifiedId(const char *schema, const char *id)
297 : {
298 94330 : return fmtQualifiedIdEnc(schema, id, getFmtEncoding());
299 : }
300 :
301 :
302 : /*
303 : * Format a Postgres version number (in the PG_VERSION_NUM integer format
304 : * returned by PQserverVersion()) as a string. This exists mainly to
305 : * encapsulate knowledge about two-part vs. three-part version numbers.
306 : *
307 : * For reentrancy, caller must supply the buffer the string is put in.
308 : * Recommended size of the buffer is 32 bytes.
309 : *
310 : * Returns address of 'buf', as a notational convenience.
311 : */
312 : char *
313 0 : formatPGVersionNumber(int version_number, bool include_minor,
314 : char *buf, size_t buflen)
315 : {
316 0 : if (version_number >= 100000)
317 : {
318 : /* New two-part style */
319 0 : if (include_minor)
320 0 : snprintf(buf, buflen, "%d.%d", version_number / 10000,
321 : version_number % 10000);
322 : else
323 0 : snprintf(buf, buflen, "%d", version_number / 10000);
324 : }
325 : else
326 : {
327 : /* Old three-part style */
328 0 : if (include_minor)
329 0 : snprintf(buf, buflen, "%d.%d.%d", version_number / 10000,
330 0 : (version_number / 100) % 100,
331 : version_number % 100);
332 : else
333 0 : snprintf(buf, buflen, "%d.%d", version_number / 10000,
334 0 : (version_number / 100) % 100);
335 : }
336 0 : return buf;
337 : }
338 :
339 :
340 : /*
341 : * Convert a string value to an SQL string literal and append it to
342 : * the given buffer. We assume the specified client_encoding and
343 : * standard_conforming_strings settings.
344 : *
345 : * This is essentially equivalent to libpq's PQescapeStringInternal,
346 : * except for the output buffer structure. We need it in situations
347 : * where we do not have a PGconn available. Where we do,
348 : * appendStringLiteralConn is a better choice.
349 : */
350 : void
351 319794 : appendStringLiteral(PQExpBuffer buf, const char *str,
352 : int encoding, bool std_strings)
353 : {
354 319794 : size_t length = strlen(str);
355 319794 : const char *source = str;
356 : char *target;
357 319794 : size_t remaining = length;
358 :
359 319794 : if (!enlargePQExpBuffer(buf, 2 * length + 2))
360 0 : return;
361 :
362 319794 : target = buf->data + buf->len;
363 319794 : *target++ = '\'';
364 :
365 5672610 : while (remaining > 0)
366 : {
367 5352816 : char c = *source;
368 : int charlen;
369 : int i;
370 :
371 : /* Fast path for plain ASCII */
372 5352816 : if (!IS_HIGHBIT_SET(c))
373 : {
374 : /* Apply quoting if needed */
375 5352410 : if (SQL_STR_DOUBLE(c, !std_strings))
376 4692 : *target++ = c;
377 : /* Copy the character */
378 5352410 : *target++ = c;
379 5352410 : source++;
380 5352410 : remaining--;
381 5352410 : continue;
382 : }
383 :
384 : /* Slow path for possible multibyte characters */
385 406 : charlen = PQmblen(source, encoding);
386 :
387 768 : if (remaining < charlen ||
388 362 : pg_encoding_verifymbchar(encoding, source, charlen) == -1)
389 : {
390 : /*
391 : * Multibyte character is invalid. It's important to verify that
392 : * as invalid multibyte characters could e.g. be used to "skip"
393 : * over quote characters, e.g. when parsing
394 : * character-by-character.
395 : *
396 : * Replace the character's first byte with an invalid sequence.
397 : * The invalid sequence ensures that the escaped string will
398 : * trigger an error on the server-side, even if we can't directly
399 : * report an error here.
400 : *
401 : * We know there's enough space for the invalid sequence because
402 : * the "target" buffer is 2 * length + 2 long, and at worst we're
403 : * replacing a single input byte with two invalid bytes.
404 : *
405 : * It would be a bit faster to verify the whole string the first
406 : * time we encounter a set highbit, but this way we can replace
407 : * just the invalid data, which probably makes it easier for users
408 : * to find the invalidly encoded portion of a larger string.
409 : */
410 70 : pg_encoding_set_invalid(encoding, target);
411 70 : target += 2;
412 :
413 : /*
414 : * Handle the following bytes as if this byte didn't exist. That's
415 : * safer in case the subsequent bytes contain important characters
416 : * for the caller (e.g. '>' in html).
417 : */
418 70 : source++;
419 70 : remaining--;
420 : }
421 : else
422 : {
423 : /* Copy the character */
424 698 : for (i = 0; i < charlen; i++)
425 : {
426 362 : *target++ = *source++;
427 362 : remaining--;
428 : }
429 : }
430 : }
431 :
432 : /* Write the terminating quote and NUL character. */
433 319794 : *target++ = '\'';
434 319794 : *target = '\0';
435 :
436 319794 : buf->len = target - buf->data;
437 : }
438 :
439 :
440 : /*
441 : * Convert a string value to an SQL string literal and append it to
442 : * the given buffer. Encoding and string syntax rules are as indicated
443 : * by current settings of the PGconn.
444 : */
445 : void
446 9192 : appendStringLiteralConn(PQExpBuffer buf, const char *str, PGconn *conn)
447 : {
448 9192 : size_t length = strlen(str);
449 :
450 : /*
451 : * XXX This is a kluge to silence escape_string_warning in our utility
452 : * programs. It should go away someday.
453 : */
454 9192 : if (strchr(str, '\\') != NULL && PQserverVersion(conn) >= 80100)
455 : {
456 : /* ensure we are not adjacent to an identifier */
457 1432 : if (buf->len > 0 && buf->data[buf->len - 1] != ' ')
458 0 : appendPQExpBufferChar(buf, ' ');
459 1432 : appendPQExpBufferChar(buf, ESCAPE_STRING_SYNTAX);
460 1432 : appendStringLiteral(buf, str, PQclientEncoding(conn), false);
461 1432 : return;
462 : }
463 : /* XXX end kluge */
464 :
465 7760 : if (!enlargePQExpBuffer(buf, 2 * length + 2))
466 0 : return;
467 7760 : appendPQExpBufferChar(buf, '\'');
468 7760 : buf->len += PQescapeStringConn(conn, buf->data + buf->len,
469 : str, length, NULL);
470 7760 : appendPQExpBufferChar(buf, '\'');
471 : }
472 :
473 :
474 : /*
475 : * Convert a string value to a dollar quoted literal and append it to
476 : * the given buffer. If the dqprefix parameter is not NULL then the
477 : * dollar quote delimiter will begin with that (after the opening $).
478 : *
479 : * No escaping is done at all on str, in compliance with the rules
480 : * for parsing dollar quoted strings. Also, we need not worry about
481 : * encoding issues.
482 : */
483 : void
484 3174 : appendStringLiteralDQ(PQExpBuffer buf, const char *str, const char *dqprefix)
485 : {
486 : static const char suffixes[] = "_XXXXXXX";
487 3174 : int nextchar = 0;
488 3174 : PQExpBuffer delimBuf = createPQExpBuffer();
489 :
490 : /* start with $ + dqprefix if not NULL */
491 3174 : appendPQExpBufferChar(delimBuf, '$');
492 3174 : if (dqprefix)
493 0 : appendPQExpBufferStr(delimBuf, dqprefix);
494 :
495 : /*
496 : * Make sure we choose a delimiter which (without the trailing $) is not
497 : * present in the string being quoted. We don't check with the trailing $
498 : * because a string ending in $foo must not be quoted with $foo$.
499 : */
500 4196 : while (strstr(str, delimBuf->data) != NULL)
501 : {
502 1022 : appendPQExpBufferChar(delimBuf, suffixes[nextchar++]);
503 1022 : nextchar %= sizeof(suffixes) - 1;
504 : }
505 :
506 : /* add trailing $ */
507 3174 : appendPQExpBufferChar(delimBuf, '$');
508 :
509 : /* quote it and we are all done */
510 3174 : appendPQExpBufferStr(buf, delimBuf->data);
511 3174 : appendPQExpBufferStr(buf, str);
512 3174 : appendPQExpBufferStr(buf, delimBuf->data);
513 :
514 3174 : destroyPQExpBuffer(delimBuf);
515 3174 : }
516 :
517 :
518 : /*
519 : * Convert a bytea value (presented as raw bytes) to an SQL string literal
520 : * and append it to the given buffer. We assume the specified
521 : * standard_conforming_strings setting.
522 : *
523 : * This is needed in situations where we do not have a PGconn available.
524 : * Where we do, PQescapeByteaConn is a better choice.
525 : */
526 : void
527 82 : appendByteaLiteral(PQExpBuffer buf, const unsigned char *str, size_t length,
528 : bool std_strings)
529 : {
530 82 : const unsigned char *source = str;
531 : char *target;
532 :
533 : static const char hextbl[] = "0123456789abcdef";
534 :
535 : /*
536 : * This implementation is hard-wired to produce hex-format output. We do
537 : * not know the server version the output will be loaded into, so making
538 : * an intelligent format choice is impossible. It might be better to
539 : * always use the old escaped format.
540 : */
541 82 : if (!enlargePQExpBuffer(buf, 2 * length + 5))
542 0 : return;
543 :
544 82 : target = buf->data + buf->len;
545 82 : *target++ = '\'';
546 82 : if (!std_strings)
547 0 : *target++ = '\\';
548 82 : *target++ = '\\';
549 82 : *target++ = 'x';
550 :
551 8086 : while (length-- > 0)
552 : {
553 8004 : unsigned char c = *source++;
554 :
555 8004 : *target++ = hextbl[(c >> 4) & 0xF];
556 8004 : *target++ = hextbl[c & 0xF];
557 : }
558 :
559 : /* Write the terminating quote and NUL character. */
560 82 : *target++ = '\'';
561 82 : *target = '\0';
562 :
563 82 : buf->len = target - buf->data;
564 : }
565 :
566 :
567 : /*
568 : * Append the given string to the shell command being built in the buffer,
569 : * with shell-style quoting as needed to create exactly one argument.
570 : *
571 : * Forbid LF or CR characters, which have scant practical use beyond designing
572 : * security breaches. The Windows command shell is unusable as a conduit for
573 : * arguments containing LF or CR characters. A future major release should
574 : * reject those characters in CREATE ROLE and CREATE DATABASE, because use
575 : * there eventually leads to errors here.
576 : *
577 : * appendShellString() simply prints an error and dies if LF or CR appears.
578 : * appendShellStringNoError() omits those characters from the result, and
579 : * returns false if there were any.
580 : */
581 : void
582 648 : appendShellString(PQExpBuffer buf, const char *str)
583 : {
584 648 : if (!appendShellStringNoError(buf, str))
585 : {
586 2 : fprintf(stderr,
587 2 : _("shell command argument contains a newline or carriage return: \"%s\"\n"),
588 : str);
589 2 : exit(EXIT_FAILURE);
590 : }
591 646 : }
592 :
593 : bool
594 648 : appendShellStringNoError(PQExpBuffer buf, const char *str)
595 : {
596 : #ifdef WIN32
597 : int backslash_run_length = 0;
598 : #endif
599 648 : bool ok = true;
600 : const char *p;
601 :
602 : /*
603 : * Don't bother with adding quotes if the string is nonempty and clearly
604 : * contains only safe characters.
605 : */
606 648 : if (*str != '\0' &&
607 648 : strspn(str, "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_./:") == strlen(str))
608 : {
609 524 : appendPQExpBufferStr(buf, str);
610 524 : return ok;
611 : }
612 :
613 : #ifndef WIN32
614 124 : appendPQExpBufferChar(buf, '\'');
615 6088 : for (p = str; *p; p++)
616 : {
617 5964 : if (*p == '\n' || *p == '\r')
618 : {
619 4 : ok = false;
620 4 : continue;
621 : }
622 :
623 5960 : if (*p == '\'')
624 172 : appendPQExpBufferStr(buf, "'\"'\"'");
625 : else
626 5788 : appendPQExpBufferChar(buf, *p);
627 : }
628 124 : appendPQExpBufferChar(buf, '\'');
629 : #else /* WIN32 */
630 :
631 : /*
632 : * A Windows system() argument experiences two layers of interpretation.
633 : * First, cmd.exe interprets the string. Its behavior is undocumented,
634 : * but a caret escapes any byte except LF or CR that would otherwise have
635 : * special meaning. Handling of a caret before LF or CR differs between
636 : * "cmd.exe /c" and other modes, and it is unusable here.
637 : *
638 : * Second, the new process parses its command line to construct argv (see
639 : * https://msdn.microsoft.com/en-us/library/17w5ykft.aspx). This treats
640 : * backslash-double quote sequences specially.
641 : */
642 : appendPQExpBufferStr(buf, "^\"");
643 : for (p = str; *p; p++)
644 : {
645 : if (*p == '\n' || *p == '\r')
646 : {
647 : ok = false;
648 : continue;
649 : }
650 :
651 : /* Change N backslashes before a double quote to 2N+1 backslashes. */
652 : if (*p == '"')
653 : {
654 : while (backslash_run_length)
655 : {
656 : appendPQExpBufferStr(buf, "^\\");
657 : backslash_run_length--;
658 : }
659 : appendPQExpBufferStr(buf, "^\\");
660 : }
661 : else if (*p == '\\')
662 : backslash_run_length++;
663 : else
664 : backslash_run_length = 0;
665 :
666 : /*
667 : * Decline to caret-escape the most mundane characters, to ease
668 : * debugging and lest we approach the command length limit.
669 : */
670 : if (!((*p >= 'a' && *p <= 'z') ||
671 : (*p >= 'A' && *p <= 'Z') ||
672 : (*p >= '0' && *p <= '9')))
673 : appendPQExpBufferChar(buf, '^');
674 : appendPQExpBufferChar(buf, *p);
675 : }
676 :
677 : /*
678 : * Change N backslashes at end of argument to 2N backslashes, because they
679 : * precede the double quote that terminates the argument.
680 : */
681 : while (backslash_run_length)
682 : {
683 : appendPQExpBufferStr(buf, "^\\");
684 : backslash_run_length--;
685 : }
686 : appendPQExpBufferStr(buf, "^\"");
687 : #endif /* WIN32 */
688 :
689 124 : return ok;
690 : }
691 :
692 :
693 : /*
694 : * Append the given string to the buffer, with suitable quoting for passing
695 : * the string as a value in a keyword/value pair in a libpq connection string.
696 : */
697 : void
698 2386 : appendConnStrVal(PQExpBuffer buf, const char *str)
699 : {
700 : const char *s;
701 : bool needquotes;
702 :
703 : /*
704 : * If the string is one or more plain ASCII characters, no need to quote
705 : * it. This is quite conservative, but better safe than sorry.
706 : */
707 2386 : needquotes = true;
708 16822 : for (s = str; *s; s++)
709 : {
710 15266 : if (!((*s >= 'a' && *s <= 'z') || (*s >= 'A' && *s <= 'Z') ||
711 2168 : (*s >= '0' && *s <= '9') || *s == '_' || *s == '.'))
712 : {
713 830 : needquotes = true;
714 830 : break;
715 : }
716 14436 : needquotes = false;
717 : }
718 :
719 2386 : if (needquotes)
720 : {
721 830 : appendPQExpBufferChar(buf, '\'');
722 21388 : while (*str)
723 : {
724 : /* ' and \ must be escaped by to \' and \\ */
725 20558 : if (*str == '\'' || *str == '\\')
726 572 : appendPQExpBufferChar(buf, '\\');
727 :
728 20558 : appendPQExpBufferChar(buf, *str);
729 20558 : str++;
730 : }
731 830 : appendPQExpBufferChar(buf, '\'');
732 : }
733 : else
734 1556 : appendPQExpBufferStr(buf, str);
735 2386 : }
736 :
737 :
738 : /*
739 : * Append a psql meta-command that connects to the given database with the
740 : * then-current connection's user, host and port.
741 : */
742 : void
743 70 : appendPsqlMetaConnect(PQExpBuffer buf, const char *dbname)
744 : {
745 : const char *s;
746 : bool complex;
747 :
748 : /*
749 : * If the name is plain ASCII characters, emit a trivial "\connect "foo"".
750 : * For other names, even many not technically requiring it, skip to the
751 : * general case. No database has a zero-length name.
752 : */
753 70 : complex = false;
754 :
755 1822 : for (s = dbname; *s; s++)
756 : {
757 1752 : if (*s == '\n' || *s == '\r')
758 : {
759 0 : fprintf(stderr,
760 0 : _("database name contains a newline or carriage return: \"%s\"\n"),
761 : dbname);
762 0 : exit(EXIT_FAILURE);
763 : }
764 :
765 1752 : if (!((*s >= 'a' && *s <= 'z') || (*s >= 'A' && *s <= 'Z') ||
766 770 : (*s >= '0' && *s <= '9') || *s == '_' || *s == '.'))
767 : {
768 654 : complex = true;
769 : }
770 : }
771 :
772 70 : if (complex)
773 : {
774 : PQExpBufferData connstr;
775 :
776 20 : initPQExpBuffer(&connstr);
777 :
778 : /*
779 : * Force the target psql's encoding to SQL_ASCII. We don't really
780 : * know the encoding of the database name, and it doesn't matter as
781 : * long as psql will forward it to the server unchanged.
782 : */
783 20 : appendPQExpBufferStr(buf, "\\encoding SQL_ASCII\n");
784 20 : appendPQExpBufferStr(buf, "\\connect -reuse-previous=on ");
785 :
786 20 : appendPQExpBufferStr(&connstr, "dbname=");
787 20 : appendConnStrVal(&connstr, dbname);
788 :
789 : /*
790 : * As long as the name does not contain a newline, SQL identifier
791 : * quoting satisfies the psql meta-command parser. Prefer not to
792 : * involve psql-interpreted single quotes, which behaved differently
793 : * before PostgreSQL 9.2.
794 : */
795 20 : appendPQExpBufferStr(buf, fmtIdEnc(connstr.data, PG_SQL_ASCII));
796 :
797 20 : termPQExpBuffer(&connstr);
798 : }
799 : else
800 : {
801 50 : appendPQExpBufferStr(buf, "\\connect ");
802 50 : appendPQExpBufferStr(buf, fmtIdEnc(dbname, PG_SQL_ASCII));
803 : }
804 70 : appendPQExpBufferChar(buf, '\n');
805 70 : }
806 :
807 :
808 : /*
809 : * Deconstruct the text representation of a 1-dimensional Postgres array
810 : * into individual items.
811 : *
812 : * On success, returns true and sets *itemarray and *nitems to describe
813 : * an array of individual strings. On parse failure, returns false;
814 : * *itemarray may exist or be NULL.
815 : *
816 : * NOTE: free'ing itemarray is sufficient to deallocate the working storage.
817 : */
818 : bool
819 92896 : parsePGArray(const char *atext, char ***itemarray, int *nitems)
820 : {
821 : int inputlen;
822 : char **items;
823 : char *strings;
824 : int curitem;
825 :
826 : /*
827 : * We expect input in the form of "{item,item,item}" where any item is
828 : * either raw data, or surrounded by double quotes (in which case embedded
829 : * characters including backslashes and quotes are backslashed).
830 : *
831 : * We build the result as an array of pointers followed by the actual
832 : * string data, all in one malloc block for convenience of deallocation.
833 : * The worst-case storage need is not more than one pointer and one
834 : * character for each input character (consider "{,,,,,,,,,,}").
835 : */
836 92896 : *itemarray = NULL;
837 92896 : *nitems = 0;
838 92896 : inputlen = strlen(atext);
839 92896 : if (inputlen < 2 || atext[0] != '{' || atext[inputlen - 1] != '}')
840 0 : return false; /* bad input */
841 92896 : items = (char **) malloc(inputlen * (sizeof(char *) + sizeof(char)));
842 92896 : if (items == NULL)
843 0 : return false; /* out of memory */
844 92896 : *itemarray = items;
845 92896 : strings = (char *) (items + inputlen);
846 :
847 92896 : atext++; /* advance over initial '{' */
848 92896 : curitem = 0;
849 254466 : while (*atext != '}')
850 : {
851 161570 : if (*atext == '\0')
852 0 : return false; /* premature end of string */
853 161570 : items[curitem] = strings;
854 3271414 : while (*atext != '}' && *atext != ',')
855 : {
856 3109844 : if (*atext == '\0')
857 0 : return false; /* premature end of string */
858 3109844 : if (*atext != '"')
859 3109454 : *strings++ = *atext++; /* copy unquoted data */
860 : else
861 : {
862 : /* process quoted substring */
863 390 : atext++;
864 13268 : while (*atext != '"')
865 : {
866 12878 : if (*atext == '\0')
867 0 : return false; /* premature end of string */
868 12878 : if (*atext == '\\')
869 : {
870 1950 : atext++;
871 1950 : if (*atext == '\0')
872 0 : return false; /* premature end of string */
873 : }
874 12878 : *strings++ = *atext++; /* copy quoted data */
875 : }
876 390 : atext++;
877 : }
878 : }
879 161570 : *strings++ = '\0';
880 161570 : if (*atext == ',')
881 71446 : atext++;
882 161570 : curitem++;
883 : }
884 92896 : if (atext[1] != '\0')
885 0 : return false; /* bogus syntax (embedded '}') */
886 92896 : *nitems = curitem;
887 92896 : return true;
888 : }
889 :
890 :
891 : /*
892 : * Append one element to the text representation of a 1-dimensional Postgres
893 : * array.
894 : *
895 : * The caller must provide the initial '{' and closing '}' of the array.
896 : * This function handles all else, including insertion of commas and
897 : * quoting of values.
898 : *
899 : * We assume that typdelim is ','.
900 : */
901 : void
902 620 : appendPGArray(PQExpBuffer buffer, const char *value)
903 : {
904 : bool needquote;
905 : const char *tmp;
906 :
907 620 : if (buffer->data[buffer->len - 1] != '{')
908 310 : appendPQExpBufferChar(buffer, ',');
909 :
910 : /* Decide if we need quotes; this should match array_out()'s choices. */
911 620 : if (value[0] == '\0')
912 0 : needquote = true; /* force quotes for empty string */
913 620 : else if (pg_strcasecmp(value, "NULL") == 0)
914 0 : needquote = true; /* force quotes for literal NULL */
915 : else
916 620 : needquote = false;
917 :
918 620 : if (!needquote)
919 : {
920 12880 : for (tmp = value; *tmp; tmp++)
921 : {
922 12468 : char ch = *tmp;
923 :
924 12468 : if (ch == '"' || ch == '\\' ||
925 12260 : ch == '{' || ch == '}' || ch == ',' ||
926 : /* these match scanner_isspace(): */
927 12260 : ch == ' ' || ch == '\t' || ch == '\n' ||
928 12260 : ch == '\r' || ch == '\v' || ch == '\f')
929 : {
930 208 : needquote = true;
931 208 : break;
932 : }
933 : }
934 : }
935 :
936 620 : if (needquote)
937 : {
938 208 : appendPQExpBufferChar(buffer, '"');
939 9048 : for (tmp = value; *tmp; tmp++)
940 : {
941 8840 : char ch = *tmp;
942 :
943 8840 : if (ch == '"' || ch == '\\')
944 1560 : appendPQExpBufferChar(buffer, '\\');
945 8840 : appendPQExpBufferChar(buffer, ch);
946 : }
947 208 : appendPQExpBufferChar(buffer, '"');
948 : }
949 : else
950 412 : appendPQExpBufferStr(buffer, value);
951 620 : }
952 :
953 :
954 : /*
955 : * Format a reloptions array and append it to the given buffer.
956 : *
957 : * "prefix" is prepended to the option names; typically it's "" or "toast.".
958 : *
959 : * Returns false if the reloptions array could not be parsed (in which case
960 : * nothing will have been appended to the buffer), or true on success.
961 : *
962 : * Note: this logic should generally match the backend's flatten_reloptions()
963 : * (in adt/ruleutils.c).
964 : */
965 : bool
966 424 : appendReloptionsArray(PQExpBuffer buffer, const char *reloptions,
967 : const char *prefix, int encoding, bool std_strings)
968 : {
969 : char **options;
970 : int noptions;
971 : int i;
972 :
973 424 : if (!parsePGArray(reloptions, &options, &noptions))
974 : {
975 0 : free(options);
976 0 : return false;
977 : }
978 :
979 966 : for (i = 0; i < noptions; i++)
980 : {
981 542 : char *option = options[i];
982 : char *name;
983 : char *separator;
984 : char *value;
985 :
986 : /*
987 : * Each array element should have the form name=value. If the "=" is
988 : * missing for some reason, treat it like an empty value.
989 : */
990 542 : name = option;
991 542 : separator = strchr(option, '=');
992 542 : if (separator)
993 : {
994 542 : *separator = '\0';
995 542 : value = separator + 1;
996 : }
997 : else
998 0 : value = "";
999 :
1000 542 : if (i > 0)
1001 118 : appendPQExpBufferStr(buffer, ", ");
1002 542 : appendPQExpBuffer(buffer, "%s%s=", prefix, fmtId(name));
1003 :
1004 : /*
1005 : * In general we need to quote the value; but to avoid unnecessary
1006 : * clutter, do not quote if it is an identifier that would not need
1007 : * quoting. (We could also allow numbers, but that is a bit trickier
1008 : * than it looks --- for example, are leading zeroes significant? We
1009 : * don't want to assume very much here about what custom reloptions
1010 : * might mean.)
1011 : */
1012 542 : if (strcmp(fmtId(value), value) == 0)
1013 64 : appendPQExpBufferStr(buffer, value);
1014 : else
1015 478 : appendStringLiteral(buffer, value, encoding, std_strings);
1016 : }
1017 :
1018 424 : free(options);
1019 :
1020 424 : return true;
1021 : }
1022 :
1023 :
1024 : /*
1025 : * processSQLNamePattern
1026 : *
1027 : * Scan a wildcard-pattern string and generate appropriate WHERE clauses
1028 : * to limit the set of objects returned. The WHERE clauses are appended
1029 : * to the already-partially-constructed query in buf. Returns whether
1030 : * any clause was added.
1031 : *
1032 : * conn: connection query will be sent to (consulted for escaping rules).
1033 : * buf: output parameter.
1034 : * pattern: user-specified pattern option, or NULL if none ("*" is implied).
1035 : * have_where: true if caller already emitted "WHERE" (clauses will be ANDed
1036 : * onto the existing WHERE clause).
1037 : * force_escape: always quote regexp special characters, even outside
1038 : * double quotes (else they are quoted only between double quotes).
1039 : * schemavar: name of query variable to match against a schema-name pattern.
1040 : * Can be NULL if no schema.
1041 : * namevar: name of query variable to match against an object-name pattern.
1042 : * altnamevar: NULL, or name of an alternative variable to match against name.
1043 : * visibilityrule: clause to use if we want to restrict to visible objects
1044 : * (for example, "pg_catalog.pg_table_is_visible(p.oid)"). Can be NULL.
1045 : * dbnamebuf: output parameter receiving the database name portion of the
1046 : * pattern, if any. Can be NULL.
1047 : * dotcnt: how many separators were parsed from the pattern, by reference.
1048 : *
1049 : * Formatting note: the text already present in buf should end with a newline.
1050 : * The appended text, if any, will end with one too.
1051 : */
1052 : bool
1053 7130 : processSQLNamePattern(PGconn *conn, PQExpBuffer buf, const char *pattern,
1054 : bool have_where, bool force_escape,
1055 : const char *schemavar, const char *namevar,
1056 : const char *altnamevar, const char *visibilityrule,
1057 : PQExpBuffer dbnamebuf, int *dotcnt)
1058 : {
1059 : PQExpBufferData schemabuf;
1060 : PQExpBufferData namebuf;
1061 7130 : bool added_clause = false;
1062 : int dcnt;
1063 :
1064 : #define WHEREAND() \
1065 : (appendPQExpBufferStr(buf, have_where ? " AND " : "WHERE "), \
1066 : have_where = true, added_clause = true)
1067 :
1068 7130 : if (dotcnt == NULL)
1069 12 : dotcnt = &dcnt;
1070 7130 : *dotcnt = 0;
1071 7130 : if (pattern == NULL)
1072 : {
1073 : /* Default: select all visible objects */
1074 490 : if (visibilityrule)
1075 : {
1076 120 : WHEREAND();
1077 120 : appendPQExpBuffer(buf, "%s\n", visibilityrule);
1078 : }
1079 490 : return added_clause;
1080 : }
1081 :
1082 6640 : initPQExpBuffer(&schemabuf);
1083 6640 : initPQExpBuffer(&namebuf);
1084 :
1085 : /*
1086 : * Convert shell-style 'pattern' into the regular expression(s) we want to
1087 : * execute. Quoting/escaping into SQL literal format will be done below
1088 : * using appendStringLiteralConn().
1089 : *
1090 : * If the caller provided a schemavar, we want to split the pattern on
1091 : * ".", otherwise not.
1092 : */
1093 6640 : patternToSQLRegex(PQclientEncoding(conn),
1094 : (schemavar ? dbnamebuf : NULL),
1095 : (schemavar ? &schemabuf : NULL),
1096 : &namebuf,
1097 : pattern, force_escape, true, dotcnt);
1098 :
1099 : /*
1100 : * Now decide what we need to emit. We may run under a hostile
1101 : * search_path, so qualify EVERY name. Note there will be a leading "^("
1102 : * in the patterns in any case.
1103 : *
1104 : * We want the regex matches to use the database's default collation where
1105 : * collation-sensitive behavior is required (for example, which characters
1106 : * match '\w'). That happened by default before PG v12, but if the server
1107 : * is >= v12 then we need to force it through explicit COLLATE clauses,
1108 : * otherwise the "C" collation attached to "name" catalog columns wins.
1109 : */
1110 6640 : if (namevar && namebuf.len > 2)
1111 : {
1112 : /* We have a name pattern, so constrain the namevar(s) */
1113 :
1114 : /* Optimize away a "*" pattern */
1115 6640 : if (strcmp(namebuf.data, "^(.*)$") != 0)
1116 : {
1117 6556 : WHEREAND();
1118 6556 : if (altnamevar)
1119 : {
1120 228 : appendPQExpBuffer(buf,
1121 : "(%s OPERATOR(pg_catalog.~) ", namevar);
1122 228 : appendStringLiteralConn(buf, namebuf.data, conn);
1123 228 : if (PQserverVersion(conn) >= 120000)
1124 228 : appendPQExpBufferStr(buf, " COLLATE pg_catalog.default");
1125 228 : appendPQExpBuffer(buf,
1126 : "\n OR %s OPERATOR(pg_catalog.~) ",
1127 : altnamevar);
1128 228 : appendStringLiteralConn(buf, namebuf.data, conn);
1129 228 : if (PQserverVersion(conn) >= 120000)
1130 228 : appendPQExpBufferStr(buf, " COLLATE pg_catalog.default");
1131 228 : appendPQExpBufferStr(buf, ")\n");
1132 : }
1133 : else
1134 : {
1135 6328 : appendPQExpBuffer(buf, "%s OPERATOR(pg_catalog.~) ", namevar);
1136 6328 : appendStringLiteralConn(buf, namebuf.data, conn);
1137 6328 : if (PQserverVersion(conn) >= 120000)
1138 6328 : appendPQExpBufferStr(buf, " COLLATE pg_catalog.default");
1139 6328 : appendPQExpBufferChar(buf, '\n');
1140 : }
1141 : }
1142 : }
1143 :
1144 6640 : if (schemavar && schemabuf.len > 2)
1145 : {
1146 : /* We have a schema pattern, so constrain the schemavar */
1147 :
1148 : /* Optimize away a "*" pattern */
1149 1436 : if (strcmp(schemabuf.data, "^(.*)$") != 0 && schemavar)
1150 : {
1151 1430 : WHEREAND();
1152 1430 : appendPQExpBuffer(buf, "%s OPERATOR(pg_catalog.~) ", schemavar);
1153 1430 : appendStringLiteralConn(buf, schemabuf.data, conn);
1154 1430 : if (PQserverVersion(conn) >= 120000)
1155 1430 : appendPQExpBufferStr(buf, " COLLATE pg_catalog.default");
1156 1430 : appendPQExpBufferChar(buf, '\n');
1157 : }
1158 : }
1159 : else
1160 : {
1161 : /* No schema pattern given, so select only visible objects */
1162 5204 : if (visibilityrule)
1163 : {
1164 4158 : WHEREAND();
1165 4158 : appendPQExpBuffer(buf, "%s\n", visibilityrule);
1166 : }
1167 : }
1168 :
1169 6640 : termPQExpBuffer(&schemabuf);
1170 6640 : termPQExpBuffer(&namebuf);
1171 :
1172 6640 : return added_clause;
1173 : #undef WHEREAND
1174 : }
1175 :
1176 : /*
1177 : * Transform a possibly qualified shell-style object name pattern into up to
1178 : * three SQL-style regular expressions, converting quotes, lower-casing
1179 : * unquoted letters, and adjusting shell-style wildcard characters into regexp
1180 : * notation.
1181 : *
1182 : * If the dbnamebuf and schemabuf arguments are non-NULL, and the pattern
1183 : * contains two or more dbname/schema/name separators, we parse the portions of
1184 : * the pattern prior to the first and second separators into dbnamebuf and
1185 : * schemabuf, and the rest into namebuf.
1186 : *
1187 : * If dbnamebuf is NULL and schemabuf is non-NULL, and the pattern contains at
1188 : * least one separator, we parse the first portion into schemabuf and the rest
1189 : * into namebuf.
1190 : *
1191 : * Otherwise, we parse all the pattern into namebuf.
1192 : *
1193 : * If the pattern contains more dotted parts than buffers to parse into, the
1194 : * extra dots will be treated as literal characters and written into the
1195 : * namebuf, though they will be counted. Callers should always check the value
1196 : * returned by reference in dotcnt and handle this error case appropriately.
1197 : *
1198 : * We surround the regexps with "^(...)$" to force them to match whole strings,
1199 : * as per SQL practice. We have to have parens in case strings contain "|",
1200 : * else the "^" and "$" will be bound into the first and last alternatives
1201 : * which is not what we want. Whether this is done for dbnamebuf is controlled
1202 : * by the want_literal_dbname parameter.
1203 : *
1204 : * The regexps we parse into the buffers are appended to the data (if any)
1205 : * already present. If we parse fewer fields than the number of buffers we
1206 : * were given, the extra buffers are unaltered.
1207 : *
1208 : * encoding: the character encoding for the given pattern
1209 : * dbnamebuf: output parameter receiving the database name portion of the
1210 : * pattern, if any. Can be NULL.
1211 : * schemabuf: output parameter receiving the schema name portion of the
1212 : * pattern, if any. Can be NULL.
1213 : * namebuf: output parameter receiving the database name portion of the
1214 : * pattern, if any. Can be NULL.
1215 : * pattern: user-specified pattern option, or NULL if none ("*" is implied).
1216 : * force_escape: always quote regexp special characters, even outside
1217 : * double quotes (else they are quoted only between double quotes).
1218 : * want_literal_dbname: if true, regexp special characters within the database
1219 : * name portion of the pattern will not be escaped, nor will the dbname be
1220 : * converted into a regular expression.
1221 : * dotcnt: output parameter receiving the number of separators parsed from the
1222 : * pattern.
1223 : */
1224 : void
1225 6844 : patternToSQLRegex(int encoding, PQExpBuffer dbnamebuf, PQExpBuffer schemabuf,
1226 : PQExpBuffer namebuf, const char *pattern, bool force_escape,
1227 : bool want_literal_dbname, int *dotcnt)
1228 : {
1229 : PQExpBufferData buf[3];
1230 : PQExpBufferData left_literal;
1231 : PQExpBuffer curbuf;
1232 : PQExpBuffer maxbuf;
1233 : int i;
1234 : bool inquotes;
1235 : bool left;
1236 : const char *cp;
1237 :
1238 : Assert(pattern != NULL);
1239 : Assert(namebuf != NULL);
1240 :
1241 : /* callers should never expect "dbname.relname" format */
1242 : Assert(dbnamebuf == NULL || schemabuf != NULL);
1243 : Assert(dotcnt != NULL);
1244 :
1245 6844 : *dotcnt = 0;
1246 6844 : inquotes = false;
1247 6844 : cp = pattern;
1248 :
1249 6844 : if (dbnamebuf != NULL)
1250 5690 : maxbuf = &buf[2];
1251 1154 : else if (schemabuf != NULL)
1252 58 : maxbuf = &buf[1];
1253 : else
1254 1096 : maxbuf = &buf[0];
1255 :
1256 6844 : curbuf = &buf[0];
1257 6844 : if (want_literal_dbname)
1258 : {
1259 6640 : left = true;
1260 6640 : initPQExpBuffer(&left_literal);
1261 : }
1262 : else
1263 204 : left = false;
1264 6844 : initPQExpBuffer(curbuf);
1265 6844 : appendPQExpBufferStr(curbuf, "^(");
1266 121206 : while (*cp)
1267 : {
1268 114362 : char ch = *cp;
1269 :
1270 114362 : if (ch == '"')
1271 : {
1272 3214 : if (inquotes && cp[1] == '"')
1273 : {
1274 : /* emit one quote, stay in inquotes mode */
1275 6 : appendPQExpBufferChar(curbuf, '"');
1276 6 : if (left)
1277 6 : appendPQExpBufferChar(&left_literal, '"');
1278 6 : cp++;
1279 : }
1280 : else
1281 3208 : inquotes = !inquotes;
1282 3214 : cp++;
1283 : }
1284 111148 : else if (!inquotes && isupper((unsigned char) ch))
1285 : {
1286 240 : appendPQExpBufferChar(curbuf,
1287 240 : pg_tolower((unsigned char) ch));
1288 240 : if (left)
1289 150 : appendPQExpBufferChar(&left_literal,
1290 150 : pg_tolower((unsigned char) ch));
1291 240 : cp++;
1292 : }
1293 110908 : else if (!inquotes && ch == '*')
1294 : {
1295 416 : appendPQExpBufferStr(curbuf, ".*");
1296 416 : if (left)
1297 310 : appendPQExpBufferChar(&left_literal, '*');
1298 416 : cp++;
1299 : }
1300 110492 : else if (!inquotes && ch == '?')
1301 : {
1302 6 : appendPQExpBufferChar(curbuf, '.');
1303 6 : if (left)
1304 6 : appendPQExpBufferChar(&left_literal, '?');
1305 6 : cp++;
1306 : }
1307 110486 : else if (!inquotes && ch == '.')
1308 : {
1309 2826 : left = false;
1310 2826 : if (dotcnt)
1311 2826 : (*dotcnt)++;
1312 2826 : if (curbuf < maxbuf)
1313 : {
1314 2242 : appendPQExpBufferStr(curbuf, ")$");
1315 2242 : curbuf++;
1316 2242 : initPQExpBuffer(curbuf);
1317 2242 : appendPQExpBufferStr(curbuf, "^(");
1318 2242 : cp++;
1319 : }
1320 : else
1321 584 : appendPQExpBufferChar(curbuf, *cp++);
1322 : }
1323 107660 : else if (ch == '$')
1324 : {
1325 : /*
1326 : * Dollar is always quoted, whether inside quotes or not. The
1327 : * reason is that it's allowed in SQL identifiers, so there's a
1328 : * significant use-case for treating it literally, while because
1329 : * we anchor the pattern automatically there is no use-case for
1330 : * having it possess its regexp meaning.
1331 : */
1332 12 : appendPQExpBufferStr(curbuf, "\\$");
1333 12 : if (left)
1334 12 : appendPQExpBufferChar(&left_literal, '$');
1335 12 : cp++;
1336 : }
1337 : else
1338 : {
1339 : /*
1340 : * Ordinary data character, transfer to pattern
1341 : *
1342 : * Inside double quotes, or at all times if force_escape is true,
1343 : * quote regexp special characters with a backslash to avoid
1344 : * regexp errors. Outside quotes, however, let them pass through
1345 : * as-is; this lets knowledgeable users build regexp expressions
1346 : * that are more powerful than shell-style patterns.
1347 : *
1348 : * As an exception to that, though, always quote "[]", as that's
1349 : * much more likely to be an attempt to write an array type name
1350 : * than it is to be the start of a regexp bracket expression.
1351 : */
1352 107648 : if ((inquotes || force_escape) &&
1353 29992 : strchr("|*+?()[]{}.^$\\", ch))
1354 3874 : appendPQExpBufferChar(curbuf, '\\');
1355 103774 : else if (ch == '[' && cp[1] == ']')
1356 6 : appendPQExpBufferChar(curbuf, '\\');
1357 107648 : i = PQmblenBounded(cp, encoding);
1358 215296 : while (i--)
1359 : {
1360 107648 : if (left)
1361 74220 : appendPQExpBufferChar(&left_literal, *cp);
1362 107648 : appendPQExpBufferChar(curbuf, *cp++);
1363 : }
1364 : }
1365 : }
1366 6844 : appendPQExpBufferStr(curbuf, ")$");
1367 :
1368 6844 : if (namebuf)
1369 : {
1370 6844 : appendPQExpBufferStr(namebuf, curbuf->data);
1371 6844 : termPQExpBuffer(curbuf);
1372 6844 : curbuf--;
1373 : }
1374 :
1375 6844 : if (schemabuf && curbuf >= buf)
1376 : {
1377 1488 : appendPQExpBufferStr(schemabuf, curbuf->data);
1378 1488 : termPQExpBuffer(curbuf);
1379 1488 : curbuf--;
1380 : }
1381 :
1382 6844 : if (dbnamebuf && curbuf >= buf)
1383 : {
1384 754 : if (want_literal_dbname)
1385 720 : appendPQExpBufferStr(dbnamebuf, left_literal.data);
1386 : else
1387 34 : appendPQExpBufferStr(dbnamebuf, curbuf->data);
1388 754 : termPQExpBuffer(curbuf);
1389 : }
1390 :
1391 6844 : if (want_literal_dbname)
1392 6640 : termPQExpBuffer(&left_literal);
1393 6844 : }
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