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(mouse-buffer-menu-mode-groups): Added "Version Control" group.
[emacs.git] / src / regex.c
blob38fc80437fd8fae3b4474dc13934b9e41c43d6ae
1 /* Extended regular expression matching and search library, version
2 0.12. (Implements POSIX draft P1003.2/D11.2, except for some of the
3 internationalization features.)
4
5 Copyright (C) 1993,94,95,96,97,98,99,2000 Free Software Foundation, Inc.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
20 USA. */
21
22 /* TODO:
23 - structure the opcode space into opcode+flag.
24 - merge with glibc's regex.[ch].
25 - replace (succeed_n + jump_n + set_number_at) with something that doesn't
26 need to modify the compiled regexp so that re_match can be reentrant.
27 - get rid of on_failure_jump_smart by doing the optimization in re_comp
28 rather than at run-time, so that re_match can be reentrant.
29 */
30
31 /* AIX requires this to be the first thing in the file. */
32 #if defined _AIX && !defined REGEX_MALLOC
33 #pragma alloca
34 #endif
35
36 #undef _GNU_SOURCE
37 #define _GNU_SOURCE
38
39 #ifdef HAVE_CONFIG_H
40 # include <config.h>
41 #endif
42
43 #if defined STDC_HEADERS && !defined emacs
44 # include <stddef.h>
45 #else
46 /* We need this for `regex.h', and perhaps for the Emacs include files. */
47 # include <sys/types.h>
48 #endif
49
50 /* Whether to use ISO C Amendment 1 wide char functions.
51 Those should not be used for Emacs since it uses its own. */
52 #if defined _LIBC
53 #define WIDE_CHAR_SUPPORT 1
54 #else
55 #define WIDE_CHAR_SUPPORT \
56 (HAVE_WCTYPE_H && HAVE_WCHAR_H && HAVE_BTOWC && !emacs)
57 #endif
58
59 /* For platform which support the ISO C amendement 1 functionality we
60 support user defined character classes. */
61 #if WIDE_CHAR_SUPPORT
62 /* Solaris 2.5 has a bug: <wchar.h> must be included before <wctype.h>. */
63 # include <wchar.h>
64 # include <wctype.h>
65 #endif
66
67 #ifdef _LIBC
68 /* We have to keep the namespace clean. */
69 # define regfree(preg) __regfree (preg)
70 # define regexec(pr, st, nm, pm, ef) __regexec (pr, st, nm, pm, ef)
71 # define regcomp(preg, pattern, cflags) __regcomp (preg, pattern, cflags)
72 # define regerror(errcode, preg, errbuf, errbuf_size) \
73 __regerror(errcode, preg, errbuf, errbuf_size)
74 # define re_set_registers(bu, re, nu, st, en) \
75 __re_set_registers (bu, re, nu, st, en)
76 # define re_match_2(bufp, string1, size1, string2, size2, pos, regs, stop) \
77 __re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
78 # define re_match(bufp, string, size, pos, regs) \
79 __re_match (bufp, string, size, pos, regs)
80 # define re_search(bufp, string, size, startpos, range, regs) \
81 __re_search (bufp, string, size, startpos, range, regs)
82 # define re_compile_pattern(pattern, length, bufp) \
83 __re_compile_pattern (pattern, length, bufp)
84 # define re_set_syntax(syntax) __re_set_syntax (syntax)
85 # define re_search_2(bufp, st1, s1, st2, s2, startpos, range, regs, stop) \
86 __re_search_2 (bufp, st1, s1, st2, s2, startpos, range, regs, stop)
87 # define re_compile_fastmap(bufp) __re_compile_fastmap (bufp)
88
89 /* Make sure we call libc's function even if the user overrides them. */
90 # define btowc __btowc
91 # define iswctype __iswctype
92 # define wctype __wctype
93
94 # define WEAK_ALIAS(a,b) weak_alias (a, b)
95
96 /* We are also using some library internals. */
97 # include <locale/localeinfo.h>
98 # include <locale/elem-hash.h>
99 # include <langinfo.h>
100 #else
101 # define WEAK_ALIAS(a,b)
102 #endif
103
104 /* This is for other GNU distributions with internationalized messages. */
105 #if HAVE_LIBINTL_H || defined _LIBC
106 # include <libintl.h>
107 #else
108 # define gettext(msgid) (msgid)
109 #endif
110
111 #ifndef gettext_noop
112 /* This define is so xgettext can find the internationalizable
113 strings. */
114 # define gettext_noop(String) String
115 #endif
116
117 /* The `emacs' switch turns on certain matching commands
118 that make sense only in Emacs. */
119 #ifdef emacs
120
121 # include "lisp.h"
122 # include "buffer.h"
123
124 /* Make syntax table lookup grant data in gl_state. */
125 # define SYNTAX_ENTRY_VIA_PROPERTY
126
127 # include "syntax.h"
128 # include "charset.h"
129 # include "category.h"
130
131 # ifdef malloc
132 # undef malloc
133 # endif
134 # define malloc xmalloc
135 # ifdef realloc
136 # undef realloc
137 # endif
138 # define realloc xrealloc
139 # ifdef free
140 # undef free
141 # endif
142 # define free xfree
143
144 /* Converts the pointer to the char to BEG-based offset from the start. */
145 # define PTR_TO_OFFSET(d) POS_AS_IN_BUFFER (POINTER_TO_OFFSET (d))
146 # define POS_AS_IN_BUFFER(p) ((p) + (NILP (re_match_object) || BUFFERP (re_match_object)))
147
148 # define RE_MULTIBYTE_P(bufp) ((bufp)->multibyte)
149 # define RE_STRING_CHAR(p, s) \
150 (multibyte ? (STRING_CHAR (p, s)) : (*(p)))
151 # define RE_STRING_CHAR_AND_LENGTH(p, s, len) \
152 (multibyte ? (STRING_CHAR_AND_LENGTH (p, s, len)) : ((len) = 1, *(p)))
153
154 /* Set C a (possibly multibyte) character before P. P points into a
155 string which is the virtual concatenation of STR1 (which ends at
156 END1) or STR2 (which ends at END2). */
157 # define GET_CHAR_BEFORE_2(c, p, str1, end1, str2, end2) \
158 do { \
159 if (multibyte) \
160 { \
161 re_char *dtemp = (p) == (str2) ? (end1) : (p); \
162 re_char *dlimit = ((p) > (str2) && (p) <= (end2)) ? (str2) : (str1); \
163 while (dtemp-- > dlimit && !CHAR_HEAD_P (*dtemp)); \
164 c = STRING_CHAR (dtemp, (p) - dtemp); \
165 } \
166 else \
167 (c = ((p) == (str2) ? (end1) : (p))[-1]); \
168 } while (0)
169
170
171 #else /* not emacs */
172
173 /* If we are not linking with Emacs proper,
174 we can't use the relocating allocator
175 even if config.h says that we can. */
176 # undef REL_ALLOC
177
178 # if defined STDC_HEADERS || defined _LIBC
179 # include <stdlib.h>
180 # else
181 char *malloc ();
182 char *realloc ();
183 # endif
184
185 /* When used in Emacs's lib-src, we need to get bzero and bcopy somehow.
186 If nothing else has been done, use the method below. */
187 # ifdef INHIBIT_STRING_HEADER
188 # if !(defined HAVE_BZERO && defined HAVE_BCOPY)
189 # if !defined bzero && !defined bcopy
190 # undef INHIBIT_STRING_HEADER
191 # endif
192 # endif
193 # endif
194
195 /* This is the normal way of making sure we have memcpy, memcmp and bzero.
196 This is used in most programs--a few other programs avoid this
197 by defining INHIBIT_STRING_HEADER. */
198 # ifndef INHIBIT_STRING_HEADER
199 # if defined HAVE_STRING_H || defined STDC_HEADERS || defined _LIBC
200 # include <string.h>
201 # ifndef bzero
202 # ifndef _LIBC
203 # define bzero(s, n) (memset (s, '\0', n), (s))
204 # else
205 # define bzero(s, n) __bzero (s, n)
206 # endif
207 # endif
208 # else
209 # include <strings.h>
210 # ifndef memcmp
211 # define memcmp(s1, s2, n) bcmp (s1, s2, n)
212 # endif
213 # ifndef memcpy
214 # define memcpy(d, s, n) (bcopy (s, d, n), (d))
215 # endif
216 # endif
217 # endif
218
219 /* Define the syntax stuff for \<, \>, etc. */
220
221 /* Sword must be nonzero for the wordchar pattern commands in re_match_2. */
222 enum syntaxcode { Swhitespace = 0, Sword = 1 };
223
224 # ifdef SWITCH_ENUM_BUG
225 # define SWITCH_ENUM_CAST(x) ((int)(x))
226 # else
227 # define SWITCH_ENUM_CAST(x) (x)
228 # endif
229
230 /* Dummy macros for non-Emacs environments. */
231 # define BASE_LEADING_CODE_P(c) (0)
232 # define CHAR_CHARSET(c) 0
233 # define CHARSET_LEADING_CODE_BASE(c) 0
234 # define MAX_MULTIBYTE_LENGTH 1
235 # define RE_MULTIBYTE_P(x) 0
236 # define WORD_BOUNDARY_P(c1, c2) (0)
237 # define CHAR_HEAD_P(p) (1)
238 # define SINGLE_BYTE_CHAR_P(c) (1)
239 # define SAME_CHARSET_P(c1, c2) (1)
240 # define MULTIBYTE_FORM_LENGTH(p, s) (1)
241 # define STRING_CHAR(p, s) (*(p))
242 # define RE_STRING_CHAR STRING_CHAR
243 # define CHAR_STRING(c, s) (*(s) = (c), 1)
244 # define STRING_CHAR_AND_LENGTH(p, s, actual_len) ((actual_len) = 1, *(p))
245 # define RE_STRING_CHAR_AND_LENGTH STRING_CHAR_AND_LENGTH
246 # define GET_CHAR_BEFORE_2(c, p, str1, end1, str2, end2) \
247 (c = ((p) == (str2) ? *((end1) - 1) : *((p) - 1)))
248 # define MAKE_CHAR(charset, c1, c2) (c1)
249 #endif /* not emacs */
250
251 #ifndef RE_TRANSLATE
252 # define RE_TRANSLATE(TBL, C) ((unsigned char)(TBL)[C])
253 # define RE_TRANSLATE_P(TBL) (TBL)
254 #endif
255 \f
256 /* Get the interface, including the syntax bits. */
257 #include "regex.h"
258
259 /* isalpha etc. are used for the character classes. */
260 #include <ctype.h>
261
262 #ifdef emacs
263
264 /* 1 if C is an ASCII character. */
265 # define IS_REAL_ASCII(c) ((c) < 0200)
266
267 /* 1 if C is a unibyte character. */
268 # define ISUNIBYTE(c) (SINGLE_BYTE_CHAR_P ((c)))
269
270 /* The Emacs definitions should not be directly affected by locales. */
271
272 /* In Emacs, these are only used for single-byte characters. */
273 # define ISDIGIT(c) ((c) >= '0' && (c) <= '9')
274 # define ISCNTRL(c) ((c) < ' ')
275 # define ISXDIGIT(c) (((c) >= '0' && (c) <= '9') \
276 || ((c) >= 'a' && (c) <= 'f') \
277 || ((c) >= 'A' && (c) <= 'F'))
278
279 /* This is only used for single-byte characters. */
280 # define ISBLANK(c) ((c) == ' ' || (c) == '\t')
281
282 /* The rest must handle multibyte characters. */
283
284 # define ISGRAPH(c) (SINGLE_BYTE_CHAR_P (c) \
285 ? (c) > ' ' && !((c) >= 0177 && (c) <= 0237) \
286 : 1)
287
288 # define ISPRINT(c) (SINGLE_BYTE_CHAR_P (c) \
289 ? (c) >= ' ' && !((c) >= 0177 && (c) <= 0237) \
290 : 1)
291
292 # define ISALNUM(c) (IS_REAL_ASCII (c) \
293 ? (((c) >= 'a' && (c) <= 'z') \
294 || ((c) >= 'A' && (c) <= 'Z') \
295 || ((c) >= '0' && (c) <= '9')) \
296 : SYNTAX (c) == Sword)
297
298 # define ISALPHA(c) (IS_REAL_ASCII (c) \
299 ? (((c) >= 'a' && (c) <= 'z') \
300 || ((c) >= 'A' && (c) <= 'Z')) \
301 : SYNTAX (c) == Sword)
302
303 # define ISLOWER(c) (LOWERCASEP (c))
304
305 # define ISPUNCT(c) (IS_REAL_ASCII (c) \
306 ? ((c) > ' ' && (c) < 0177 \
307 && !(((c) >= 'a' && (c) <= 'z') \
308 || ((c) >= 'A' && (c) <= 'Z') \
309 || ((c) >= '0' && (c) <= '9'))) \
310 : SYNTAX (c) != Sword)
311
312 # define ISSPACE(c) (SYNTAX (c) == Swhitespace)
313
314 # define ISUPPER(c) (UPPERCASEP (c))
315
316 # define ISWORD(c) (SYNTAX (c) == Sword)
317
318 #else /* not emacs */
319
320 /* Jim Meyering writes:
321
322 "... Some ctype macros are valid only for character codes that
323 isascii says are ASCII (SGI's IRIX-4.0.5 is one such system --when
324 using /bin/cc or gcc but without giving an ansi option). So, all
325 ctype uses should be through macros like ISPRINT... If
326 STDC_HEADERS is defined, then autoconf has verified that the ctype
327 macros don't need to be guarded with references to isascii. ...
328 Defining isascii to 1 should let any compiler worth its salt
329 eliminate the && through constant folding."
330 Solaris defines some of these symbols so we must undefine them first. */
331
332 # undef ISASCII
333 # if defined STDC_HEADERS || (!defined isascii && !defined HAVE_ISASCII)
334 # define ISASCII(c) 1
335 # else
336 # define ISASCII(c) isascii(c)
337 # endif
338
339 /* 1 if C is an ASCII character. */
340 # define IS_REAL_ASCII(c) ((c) < 0200)
341
342 /* This distinction is not meaningful, except in Emacs. */
343 # define ISUNIBYTE(c) 1
344
345 # ifdef isblank
346 # define ISBLANK(c) (ISASCII (c) && isblank (c))
347 # else
348 # define ISBLANK(c) ((c) == ' ' || (c) == '\t')
349 # endif
350 # ifdef isgraph
351 # define ISGRAPH(c) (ISASCII (c) && isgraph (c))
352 # else
353 # define ISGRAPH(c) (ISASCII (c) && isprint (c) && !isspace (c))
354 # endif
355
356 # undef ISPRINT
357 # define ISPRINT(c) (ISASCII (c) && isprint (c))
358 # define ISDIGIT(c) (ISASCII (c) && isdigit (c))
359 # define ISALNUM(c) (ISASCII (c) && isalnum (c))
360 # define ISALPHA(c) (ISASCII (c) && isalpha (c))
361 # define ISCNTRL(c) (ISASCII (c) && iscntrl (c))
362 # define ISLOWER(c) (ISASCII (c) && islower (c))
363 # define ISPUNCT(c) (ISASCII (c) && ispunct (c))
364 # define ISSPACE(c) (ISASCII (c) && isspace (c))
365 # define ISUPPER(c) (ISASCII (c) && isupper (c))
366 # define ISXDIGIT(c) (ISASCII (c) && isxdigit (c))
367
368 # define ISWORD(c) ISALPHA(c)
369
370 # ifdef _tolower
371 # define TOLOWER(c) _tolower(c)
372 # else
373 # define TOLOWER(c) tolower(c)
374 # endif
375
376 /* How many characters in the character set. */
377 # define CHAR_SET_SIZE 256
378
379 # ifdef SYNTAX_TABLE
380
381 extern char *re_syntax_table;
382
383 # else /* not SYNTAX_TABLE */
384
385 static char re_syntax_table[CHAR_SET_SIZE];
386
387 static void
388 init_syntax_once ()
389 {
390 register int c;
391 static int done = 0;
392
393 if (done)
394 return;
395
396 bzero (re_syntax_table, sizeof re_syntax_table);
397
398 for (c = 0; c < CHAR_SET_SIZE; ++c)
399 if (ISALNUM (c))
400 re_syntax_table[c] = Sword;
401
402 re_syntax_table['_'] = Sword;
403
404 done = 1;
405 }
406
407 # endif /* not SYNTAX_TABLE */
408
409 # define SYNTAX(c) re_syntax_table[(c)]
410
411 #endif /* not emacs */
412 \f
413 #ifndef NULL
414 # define NULL (void *)0
415 #endif
416
417 /* We remove any previous definition of `SIGN_EXTEND_CHAR',
418 since ours (we hope) works properly with all combinations of
419 machines, compilers, `char' and `unsigned char' argument types.
420 (Per Bothner suggested the basic approach.) */
421 #undef SIGN_EXTEND_CHAR
422 #if __STDC__
423 # define SIGN_EXTEND_CHAR(c) ((signed char) (c))
424 #else /* not __STDC__ */
425 /* As in Harbison and Steele. */
426 # define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128)
427 #endif
428 \f
429 /* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we
430 use `alloca' instead of `malloc'. This is because using malloc in
431 re_search* or re_match* could cause memory leaks when C-g is used in
432 Emacs; also, malloc is slower and causes storage fragmentation. On
433 the other hand, malloc is more portable, and easier to debug.
434
435 Because we sometimes use alloca, some routines have to be macros,
436 not functions -- `alloca'-allocated space disappears at the end of the
437 function it is called in. */
438
439 #ifdef REGEX_MALLOC
440
441 # define REGEX_ALLOCATE malloc
442 # define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
443 # define REGEX_FREE free
444
445 #else /* not REGEX_MALLOC */
446
447 /* Emacs already defines alloca, sometimes. */
448 # ifndef alloca
449
450 /* Make alloca work the best possible way. */
451 # ifdef __GNUC__
452 # define alloca __builtin_alloca
453 # else /* not __GNUC__ */
454 # if HAVE_ALLOCA_H
455 # include <alloca.h>
456 # endif /* HAVE_ALLOCA_H */
457 # endif /* not __GNUC__ */
458
459 # endif /* not alloca */
460
461 # define REGEX_ALLOCATE alloca
462
463 /* Assumes a `char *destination' variable. */
464 # define REGEX_REALLOCATE(source, osize, nsize) \
465 (destination = (char *) alloca (nsize), \
466 memcpy (destination, source, osize))
467
468 /* No need to do anything to free, after alloca. */
469 # define REGEX_FREE(arg) ((void)0) /* Do nothing! But inhibit gcc warning. */
470
471 #endif /* not REGEX_MALLOC */
472
473 /* Define how to allocate the failure stack. */
474
475 #if defined REL_ALLOC && defined REGEX_MALLOC
476
477 # define REGEX_ALLOCATE_STACK(size) \
478 r_alloc (&failure_stack_ptr, (size))
479 # define REGEX_REALLOCATE_STACK(source, osize, nsize) \
480 r_re_alloc (&failure_stack_ptr, (nsize))
481 # define REGEX_FREE_STACK(ptr) \
482 r_alloc_free (&failure_stack_ptr)
483
484 #else /* not using relocating allocator */
485
486 # ifdef REGEX_MALLOC
487
488 # define REGEX_ALLOCATE_STACK malloc
489 # define REGEX_REALLOCATE_STACK(source, osize, nsize) realloc (source, nsize)
490 # define REGEX_FREE_STACK free
491
492 # else /* not REGEX_MALLOC */
493
494 # define REGEX_ALLOCATE_STACK alloca
495
496 # define REGEX_REALLOCATE_STACK(source, osize, nsize) \
497 REGEX_REALLOCATE (source, osize, nsize)
498 /* No need to explicitly free anything. */
499 # define REGEX_FREE_STACK(arg) ((void)0)
500
501 # endif /* not REGEX_MALLOC */
502 #endif /* not using relocating allocator */
503
504
505 /* True if `size1' is non-NULL and PTR is pointing anywhere inside
506 `string1' or just past its end. This works if PTR is NULL, which is
507 a good thing. */
508 #define FIRST_STRING_P(ptr) \
509 (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
510
511 /* (Re)Allocate N items of type T using malloc, or fail. */
512 #define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
513 #define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
514 #define RETALLOC_IF(addr, n, t) \
515 if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
516 #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
517
518 #define BYTEWIDTH 8 /* In bits. */
519
520 #define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
521
522 #undef MAX
523 #undef MIN
524 #define MAX(a, b) ((a) > (b) ? (a) : (b))
525 #define MIN(a, b) ((a) < (b) ? (a) : (b))
526
527 /* Type of source-pattern and string chars. */
528 typedef const unsigned char re_char;
529
530 typedef char boolean;
531 #define false 0
532 #define true 1
533
534 static int re_match_2_internal _RE_ARGS ((struct re_pattern_buffer *bufp,
535 re_char *string1, int size1,
536 re_char *string2, int size2,
537 int pos,
538 struct re_registers *regs,
539 int stop));
540 \f
541 /* These are the command codes that appear in compiled regular
542 expressions. Some opcodes are followed by argument bytes. A
543 command code can specify any interpretation whatsoever for its
544 arguments. Zero bytes may appear in the compiled regular expression. */
545
546 typedef enum
547 {
548 no_op = 0,
549
550 /* Succeed right away--no more backtracking. */
551 succeed,
552
553 /* Followed by one byte giving n, then by n literal bytes. */
554 exactn,
555
556 /* Matches any (more or less) character. */
557 anychar,
558
559 /* Matches any one char belonging to specified set. First
560 following byte is number of bitmap bytes. Then come bytes
561 for a bitmap saying which chars are in. Bits in each byte
562 are ordered low-bit-first. A character is in the set if its
563 bit is 1. A character too large to have a bit in the map is
564 automatically not in the set.
565
566 If the length byte has the 0x80 bit set, then that stuff
567 is followed by a range table:
568 2 bytes of flags for character sets (low 8 bits, high 8 bits)
569 See RANGE_TABLE_WORK_BITS below.
570 2 bytes, the number of pairs that follow (upto 32767)
571 pairs, each 2 multibyte characters,
572 each multibyte character represented as 3 bytes. */
573 charset,
574
575 /* Same parameters as charset, but match any character that is
576 not one of those specified. */
577 charset_not,
578
579 /* Start remembering the text that is matched, for storing in a
580 register. Followed by one byte with the register number, in
581 the range 0 to one less than the pattern buffer's re_nsub
582 field. */
583 start_memory,
584
585 /* Stop remembering the text that is matched and store it in a
586 memory register. Followed by one byte with the register
587 number, in the range 0 to one less than `re_nsub' in the
588 pattern buffer. */
589 stop_memory,
590
591 /* Match a duplicate of something remembered. Followed by one
592 byte containing the register number. */
593 duplicate,
594
595 /* Fail unless at beginning of line. */
596 begline,
597
598 /* Fail unless at end of line. */
599 endline,
600
601 /* Succeeds if at beginning of buffer (if emacs) or at beginning
602 of string to be matched (if not). */
603 begbuf,
604
605 /* Analogously, for end of buffer/string. */
606 endbuf,
607
608 /* Followed by two byte relative address to which to jump. */
609 jump,
610
611 /* Followed by two-byte relative address of place to resume at
612 in case of failure. */
613 on_failure_jump,
614
615 /* Like on_failure_jump, but pushes a placeholder instead of the
616 current string position when executed. */
617 on_failure_keep_string_jump,
618
619 /* Just like `on_failure_jump', except that it checks that we
620 don't get stuck in an infinite loop (matching an empty string
621 indefinitely). */
622 on_failure_jump_loop,
623
624 /* Just like `on_failure_jump_loop', except that it checks for
625 a different kind of loop (the kind that shows up with non-greedy
626 operators). This operation has to be immediately preceded
627 by a `no_op'. */
628 on_failure_jump_nastyloop,
629
630 /* A smart `on_failure_jump' used for greedy * and + operators.
631 It analyses the loop before which it is put and if the
632 loop does not require backtracking, it changes itself to
633 `on_failure_keep_string_jump' and short-circuits the loop,
634 else it just defaults to changing itself into `on_failure_jump'.
635 It assumes that it is pointing to just past a `jump'. */
636 on_failure_jump_smart,
637
638 /* Followed by two-byte relative address and two-byte number n.
639 After matching N times, jump to the address upon failure.
640 Does not work if N starts at 0: use on_failure_jump_loop
641 instead. */
642 succeed_n,
643
644 /* Followed by two-byte relative address, and two-byte number n.
645 Jump to the address N times, then fail. */
646 jump_n,
647
648 /* Set the following two-byte relative address to the
649 subsequent two-byte number. The address *includes* the two
650 bytes of number. */
651 set_number_at,
652
653 wordbeg, /* Succeeds if at word beginning. */
654 wordend, /* Succeeds if at word end. */
655
656 wordbound, /* Succeeds if at a word boundary. */
657 notwordbound, /* Succeeds if not at a word boundary. */
658
659 /* Matches any character whose syntax is specified. Followed by
660 a byte which contains a syntax code, e.g., Sword. */
661 syntaxspec,
662
663 /* Matches any character whose syntax is not that specified. */
664 notsyntaxspec
665
666 #ifdef emacs
667 ,before_dot, /* Succeeds if before point. */
668 at_dot, /* Succeeds if at point. */
669 after_dot, /* Succeeds if after point. */
670
671 /* Matches any character whose category-set contains the specified
672 category. The operator is followed by a byte which contains a
673 category code (mnemonic ASCII character). */
674 categoryspec,
675
676 /* Matches any character whose category-set does not contain the
677 specified category. The operator is followed by a byte which
678 contains the category code (mnemonic ASCII character). */
679 notcategoryspec
680 #endif /* emacs */
681 } re_opcode_t;
682 \f
683 /* Common operations on the compiled pattern. */
684
685 /* Store NUMBER in two contiguous bytes starting at DESTINATION. */
686
687 #define STORE_NUMBER(destination, number) \
688 do { \
689 (destination)[0] = (number) & 0377; \
690 (destination)[1] = (number) >> 8; \
691 } while (0)
692
693 /* Same as STORE_NUMBER, except increment DESTINATION to
694 the byte after where the number is stored. Therefore, DESTINATION
695 must be an lvalue. */
696
697 #define STORE_NUMBER_AND_INCR(destination, number) \
698 do { \
699 STORE_NUMBER (destination, number); \
700 (destination) += 2; \
701 } while (0)
702
703 /* Put into DESTINATION a number stored in two contiguous bytes starting
704 at SOURCE. */
705
706 #define EXTRACT_NUMBER(destination, source) \
707 do { \
708 (destination) = *(source) & 0377; \
709 (destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8; \
710 } while (0)
711
712 #ifdef DEBUG
713 static void extract_number _RE_ARGS ((int *dest, re_char *source));
714 static void
715 extract_number (dest, source)
716 int *dest;
717 re_char *source;
718 {
719 int temp = SIGN_EXTEND_CHAR (*(source + 1));
720 *dest = *source & 0377;
721 *dest += temp << 8;
722 }
723
724 # ifndef EXTRACT_MACROS /* To debug the macros. */
725 # undef EXTRACT_NUMBER
726 # define EXTRACT_NUMBER(dest, src) extract_number (&dest, src)
727 # endif /* not EXTRACT_MACROS */
728
729 #endif /* DEBUG */
730
731 /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
732 SOURCE must be an lvalue. */
733
734 #define EXTRACT_NUMBER_AND_INCR(destination, source) \
735 do { \
736 EXTRACT_NUMBER (destination, source); \
737 (source) += 2; \
738 } while (0)
739
740 #ifdef DEBUG
741 static void extract_number_and_incr _RE_ARGS ((int *destination,
742 re_char **source));
743 static void
744 extract_number_and_incr (destination, source)
745 int *destination;
746 re_char **source;
747 {
748 extract_number (destination, *source);
749 *source += 2;
750 }
751
752 # ifndef EXTRACT_MACROS
753 # undef EXTRACT_NUMBER_AND_INCR
754 # define EXTRACT_NUMBER_AND_INCR(dest, src) \
755 extract_number_and_incr (&dest, &src)
756 # endif /* not EXTRACT_MACROS */
757
758 #endif /* DEBUG */
759 \f
760 /* Store a multibyte character in three contiguous bytes starting
761 DESTINATION, and increment DESTINATION to the byte after where the
762 character is stored. Therefore, DESTINATION must be an lvalue. */
763
764 #define STORE_CHARACTER_AND_INCR(destination, character) \
765 do { \
766 (destination)[0] = (character) & 0377; \
767 (destination)[1] = ((character) >> 8) & 0377; \
768 (destination)[2] = (character) >> 16; \
769 (destination) += 3; \
770 } while (0)
771
772 /* Put into DESTINATION a character stored in three contiguous bytes
773 starting at SOURCE. */
774
775 #define EXTRACT_CHARACTER(destination, source) \
776 do { \
777 (destination) = ((source)[0] \
778 | ((source)[1] << 8) \
779 | ((source)[2] << 16)); \
780 } while (0)
781
782
783 /* Macros for charset. */
784
785 /* Size of bitmap of charset P in bytes. P is a start of charset,
786 i.e. *P is (re_opcode_t) charset or (re_opcode_t) charset_not. */
787 #define CHARSET_BITMAP_SIZE(p) ((p)[1] & 0x7F)
788
789 /* Nonzero if charset P has range table. */
790 #define CHARSET_RANGE_TABLE_EXISTS_P(p) ((p)[1] & 0x80)
791
792 /* Return the address of range table of charset P. But not the start
793 of table itself, but the before where the number of ranges is
794 stored. `2 +' means to skip re_opcode_t and size of bitmap,
795 and the 2 bytes of flags at the start of the range table. */
796 #define CHARSET_RANGE_TABLE(p) (&(p)[4 + CHARSET_BITMAP_SIZE (p)])
797
798 /* Extract the bit flags that start a range table. */
799 #define CHARSET_RANGE_TABLE_BITS(p) \
800 ((p)[2 + CHARSET_BITMAP_SIZE (p)] \
801 + (p)[3 + CHARSET_BITMAP_SIZE (p)] * 0x100)
802
803 /* Test if C is listed in the bitmap of charset P. */
804 #define CHARSET_LOOKUP_BITMAP(p, c) \
805 ((c) < CHARSET_BITMAP_SIZE (p) * BYTEWIDTH \
806 && (p)[2 + (c) / BYTEWIDTH] & (1 << ((c) % BYTEWIDTH)))
807
808 /* Return the address of end of RANGE_TABLE. COUNT is number of
809 ranges (which is a pair of (start, end)) in the RANGE_TABLE. `* 2'
810 is start of range and end of range. `* 3' is size of each start
811 and end. */
812 #define CHARSET_RANGE_TABLE_END(range_table, count) \
813 ((range_table) + (count) * 2 * 3)
814
815 /* Test if C is in RANGE_TABLE. A flag NOT is negated if C is in.
816 COUNT is number of ranges in RANGE_TABLE. */
817 #define CHARSET_LOOKUP_RANGE_TABLE_RAW(not, c, range_table, count) \
818 do \
819 { \
820 re_wchar_t range_start, range_end; \
821 re_char *p; \
822 re_char *range_table_end \
823 = CHARSET_RANGE_TABLE_END ((range_table), (count)); \
824 \
825 for (p = (range_table); p < range_table_end; p += 2 * 3) \
826 { \
827 EXTRACT_CHARACTER (range_start, p); \
828 EXTRACT_CHARACTER (range_end, p + 3); \
829 \
830 if (range_start <= (c) && (c) <= range_end) \
831 { \
832 (not) = !(not); \
833 break; \
834 } \
835 } \
836 } \
837 while (0)
838
839 /* Test if C is in range table of CHARSET. The flag NOT is negated if
840 C is listed in it. */
841 #define CHARSET_LOOKUP_RANGE_TABLE(not, c, charset) \
842 do \
843 { \
844 /* Number of ranges in range table. */ \
845 int count; \
846 re_char *range_table = CHARSET_RANGE_TABLE (charset); \
847 \
848 EXTRACT_NUMBER_AND_INCR (count, range_table); \
849 CHARSET_LOOKUP_RANGE_TABLE_RAW ((not), (c), range_table, count); \
850 } \
851 while (0)
852 \f
853 /* If DEBUG is defined, Regex prints many voluminous messages about what
854 it is doing (if the variable `debug' is nonzero). If linked with the
855 main program in `iregex.c', you can enter patterns and strings
856 interactively. And if linked with the main program in `main.c' and
857 the other test files, you can run the already-written tests. */
858
859 #ifdef DEBUG
860
861 /* We use standard I/O for debugging. */
862 # include <stdio.h>
863
864 /* It is useful to test things that ``must'' be true when debugging. */
865 # include <assert.h>
866
867 static int debug = -100000;
868
869 # define DEBUG_STATEMENT(e) e
870 # define DEBUG_PRINT1(x) if (debug > 0) printf (x)
871 # define DEBUG_PRINT2(x1, x2) if (debug > 0) printf (x1, x2)
872 # define DEBUG_PRINT3(x1, x2, x3) if (debug > 0) printf (x1, x2, x3)
873 # define DEBUG_PRINT4(x1, x2, x3, x4) if (debug > 0) printf (x1, x2, x3, x4)
874 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) \
875 if (debug > 0) print_partial_compiled_pattern (s, e)
876 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) \
877 if (debug > 0) print_double_string (w, s1, sz1, s2, sz2)
878
879
880 /* Print the fastmap in human-readable form. */
881
882 void
883 print_fastmap (fastmap)
884 char *fastmap;
885 {
886 unsigned was_a_range = 0;
887 unsigned i = 0;
888
889 while (i < (1 << BYTEWIDTH))
890 {
891 if (fastmap[i++])
892 {
893 was_a_range = 0;
894 putchar (i - 1);
895 while (i < (1 << BYTEWIDTH) && fastmap[i])
896 {
897 was_a_range = 1;
898 i++;
899 }
900 if (was_a_range)
901 {
902 printf ("-");
903 putchar (i - 1);
904 }
905 }
906 }
907 putchar ('\n');
908 }
909
910
911 /* Print a compiled pattern string in human-readable form, starting at
912 the START pointer into it and ending just before the pointer END. */
913
914 void
915 print_partial_compiled_pattern (start, end)
916 re_char *start;
917 re_char *end;
918 {
919 int mcnt, mcnt2;
920 re_char *p = start;
921 re_char *pend = end;
922
923 if (start == NULL)
924 {
925 printf ("(null)\n");
926 return;
927 }
928
929 /* Loop over pattern commands. */
930 while (p < pend)
931 {
932 printf ("%d:\t", p - start);
933
934 switch ((re_opcode_t) *p++)
935 {
936 case no_op:
937 printf ("/no_op");
938 break;
939
940 case succeed:
941 printf ("/succeed");
942 break;
943
944 case exactn:
945 mcnt = *p++;
946 printf ("/exactn/%d", mcnt);
947 do
948 {
949 putchar ('/');
950 putchar (*p++);
951 }
952 while (--mcnt);
953 break;
954
955 case start_memory:
956 printf ("/start_memory/%d", *p++);
957 break;
958
959 case stop_memory:
960 printf ("/stop_memory/%d", *p++);
961 break;
962
963 case duplicate:
964 printf ("/duplicate/%d", *p++);
965 break;
966
967 case anychar:
968 printf ("/anychar");
969 break;
970
971 case charset:
972 case charset_not:
973 {
974 register int c, last = -100;
975 register int in_range = 0;
976 int length = CHARSET_BITMAP_SIZE (p - 1);
977 int has_range_table = CHARSET_RANGE_TABLE_EXISTS_P (p - 1);
978
979 printf ("/charset [%s",
980 (re_opcode_t) *(p - 1) == charset_not ? "^" : "");
981
982 assert (p + *p < pend);
983
984 for (c = 0; c < 256; c++)
985 if (c / 8 < length
986 && (p[1 + (c/8)] & (1 << (c % 8))))
987 {
988 /* Are we starting a range? */
989 if (last + 1 == c && ! in_range)
990 {
991 putchar ('-');
992 in_range = 1;
993 }
994 /* Have we broken a range? */
995 else if (last + 1 != c && in_range)
996 {
997 putchar (last);
998 in_range = 0;
999 }
1000
1001 if (! in_range)
1002 putchar (c);
1003
1004 last = c;
1005 }
1006
1007 if (in_range)
1008 putchar (last);
1009
1010 putchar (']');
1011
1012 p += 1 + length;
1013
1014 if (has_range_table)
1015 {
1016 int count;
1017 printf ("has-range-table");
1018
1019 /* ??? Should print the range table; for now, just skip it. */
1020 p += 2; /* skip range table bits */
1021 EXTRACT_NUMBER_AND_INCR (count, p);
1022 p = CHARSET_RANGE_TABLE_END (p, count);
1023 }
1024 }
1025 break;
1026
1027 case begline:
1028 printf ("/begline");
1029 break;
1030
1031 case endline:
1032 printf ("/endline");
1033 break;
1034
1035 case on_failure_jump:
1036 extract_number_and_incr (&mcnt, &p);
1037 printf ("/on_failure_jump to %d", p + mcnt - start);
1038 break;
1039
1040 case on_failure_keep_string_jump:
1041 extract_number_and_incr (&mcnt, &p);
1042 printf ("/on_failure_keep_string_jump to %d", p + mcnt - start);
1043 break;
1044
1045 case on_failure_jump_nastyloop:
1046 extract_number_and_incr (&mcnt, &p);
1047 printf ("/on_failure_jump_nastyloop to %d", p + mcnt - start);
1048 break;
1049
1050 case on_failure_jump_loop:
1051 extract_number_and_incr (&mcnt, &p);
1052 printf ("/on_failure_jump_loop to %d", p + mcnt - start);
1053 break;
1054
1055 case on_failure_jump_smart:
1056 extract_number_and_incr (&mcnt, &p);
1057 printf ("/on_failure_jump_smart to %d", p + mcnt - start);
1058 break;
1059
1060 case jump:
1061 extract_number_and_incr (&mcnt, &p);
1062 printf ("/jump to %d", p + mcnt - start);
1063 break;
1064
1065 case succeed_n:
1066 extract_number_and_incr (&mcnt, &p);
1067 extract_number_and_incr (&mcnt2, &p);
1068 printf ("/succeed_n to %d, %d times", p - 2 + mcnt - start, mcnt2);
1069 break;
1070
1071 case jump_n:
1072 extract_number_and_incr (&mcnt, &p);
1073 extract_number_and_incr (&mcnt2, &p);
1074 printf ("/jump_n to %d, %d times", p - 2 + mcnt - start, mcnt2);
1075 break;
1076
1077 case set_number_at:
1078 extract_number_and_incr (&mcnt, &p);
1079 extract_number_and_incr (&mcnt2, &p);
1080 printf ("/set_number_at location %d to %d", p - 2 + mcnt - start, mcnt2);
1081 break;
1082
1083 case wordbound:
1084 printf ("/wordbound");
1085 break;
1086
1087 case notwordbound:
1088 printf ("/notwordbound");
1089 break;
1090
1091 case wordbeg:
1092 printf ("/wordbeg");
1093 break;
1094
1095 case wordend:
1096 printf ("/wordend");
1097
1098 case syntaxspec:
1099 printf ("/syntaxspec");
1100 mcnt = *p++;
1101 printf ("/%d", mcnt);
1102 break;
1103
1104 case notsyntaxspec:
1105 printf ("/notsyntaxspec");
1106 mcnt = *p++;
1107 printf ("/%d", mcnt);
1108 break;
1109
1110 # ifdef emacs
1111 case before_dot:
1112 printf ("/before_dot");
1113 break;
1114
1115 case at_dot:
1116 printf ("/at_dot");
1117 break;
1118
1119 case after_dot:
1120 printf ("/after_dot");
1121 break;
1122
1123 case categoryspec:
1124 printf ("/categoryspec");
1125 mcnt = *p++;
1126 printf ("/%d", mcnt);
1127 break;
1128
1129 case notcategoryspec:
1130 printf ("/notcategoryspec");
1131 mcnt = *p++;
1132 printf ("/%d", mcnt);
1133 break;
1134 # endif /* emacs */
1135
1136 case begbuf:
1137 printf ("/begbuf");
1138 break;
1139
1140 case endbuf:
1141 printf ("/endbuf");
1142 break;
1143
1144 default:
1145 printf ("?%d", *(p-1));
1146 }
1147
1148 putchar ('\n');
1149 }
1150
1151 printf ("%d:\tend of pattern.\n", p - start);
1152 }
1153
1154
1155 void
1156 print_compiled_pattern (bufp)
1157 struct re_pattern_buffer *bufp;
1158 {
1159 re_char *buffer = bufp->buffer;
1160
1161 print_partial_compiled_pattern (buffer, buffer + bufp->used);
1162 printf ("%ld bytes used/%ld bytes allocated.\n",
1163 bufp->used, bufp->allocated);
1164
1165 if (bufp->fastmap_accurate && bufp->fastmap)
1166 {
1167 printf ("fastmap: ");
1168 print_fastmap (bufp->fastmap);
1169 }
1170
1171 printf ("re_nsub: %d\t", bufp->re_nsub);
1172 printf ("regs_alloc: %d\t", bufp->regs_allocated);
1173 printf ("can_be_null: %d\t", bufp->can_be_null);
1174 printf ("no_sub: %d\t", bufp->no_sub);
1175 printf ("not_bol: %d\t", bufp->not_bol);
1176 printf ("not_eol: %d\t", bufp->not_eol);
1177 printf ("syntax: %lx\n", bufp->syntax);
1178 fflush (stdout);
1179 /* Perhaps we should print the translate table? */
1180 }
1181
1182
1183 void
1184 print_double_string (where, string1, size1, string2, size2)
1185 re_char *where;
1186 re_char *string1;
1187 re_char *string2;
1188 int size1;
1189 int size2;
1190 {
1191 int this_char;
1192
1193 if (where == NULL)
1194 printf ("(null)");
1195 else
1196 {
1197 if (FIRST_STRING_P (where))
1198 {
1199 for (this_char = where - string1; this_char < size1; this_char++)
1200 putchar (string1[this_char]);
1201
1202 where = string2;
1203 }
1204
1205 for (this_char = where - string2; this_char < size2; this_char++)
1206 putchar (string2[this_char]);
1207 }
1208 }
1209
1210 #else /* not DEBUG */
1211
1212 # undef assert
1213 # define assert(e)
1214
1215 # define DEBUG_STATEMENT(e)
1216 # define DEBUG_PRINT1(x)
1217 # define DEBUG_PRINT2(x1, x2)
1218 # define DEBUG_PRINT3(x1, x2, x3)
1219 # define DEBUG_PRINT4(x1, x2, x3, x4)
1220 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
1221 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
1222
1223 #endif /* not DEBUG */
1224 \f
1225 /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
1226 also be assigned to arbitrarily: each pattern buffer stores its own
1227 syntax, so it can be changed between regex compilations. */
1228 /* This has no initializer because initialized variables in Emacs
1229 become read-only after dumping. */
1230 reg_syntax_t re_syntax_options;
1231
1232
1233 /* Specify the precise syntax of regexps for compilation. This provides
1234 for compatibility for various utilities which historically have
1235 different, incompatible syntaxes.
1236
1237 The argument SYNTAX is a bit mask comprised of the various bits
1238 defined in regex.h. We return the old syntax. */
1239
1240 reg_syntax_t
1241 re_set_syntax (syntax)
1242 reg_syntax_t syntax;
1243 {
1244 reg_syntax_t ret = re_syntax_options;
1245
1246 re_syntax_options = syntax;
1247 return ret;
1248 }
1249 WEAK_ALIAS (__re_set_syntax, re_set_syntax)
1250 \f
1251 /* This table gives an error message for each of the error codes listed
1252 in regex.h. Obviously the order here has to be same as there.
1253 POSIX doesn't require that we do anything for REG_NOERROR,
1254 but why not be nice? */
1255
1256 static const char *re_error_msgid[] =
1257 {
1258 gettext_noop ("Success"), /* REG_NOERROR */
1259 gettext_noop ("No match"), /* REG_NOMATCH */
1260 gettext_noop ("Invalid regular expression"), /* REG_BADPAT */
1261 gettext_noop ("Invalid collation character"), /* REG_ECOLLATE */
1262 gettext_noop ("Invalid character class name"), /* REG_ECTYPE */
1263 gettext_noop ("Trailing backslash"), /* REG_EESCAPE */
1264 gettext_noop ("Invalid back reference"), /* REG_ESUBREG */
1265 gettext_noop ("Unmatched [ or [^"), /* REG_EBRACK */
1266 gettext_noop ("Unmatched ( or \\("), /* REG_EPAREN */
1267 gettext_noop ("Unmatched \\{"), /* REG_EBRACE */
1268 gettext_noop ("Invalid content of \\{\\}"), /* REG_BADBR */
1269 gettext_noop ("Invalid range end"), /* REG_ERANGE */
1270 gettext_noop ("Memory exhausted"), /* REG_ESPACE */
1271 gettext_noop ("Invalid preceding regular expression"), /* REG_BADRPT */
1272 gettext_noop ("Premature end of regular expression"), /* REG_EEND */
1273 gettext_noop ("Regular expression too big"), /* REG_ESIZE */
1274 gettext_noop ("Unmatched ) or \\)"), /* REG_ERPAREN */
1275 };
1276 \f
1277 /* Avoiding alloca during matching, to placate r_alloc. */
1278
1279 /* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
1280 searching and matching functions should not call alloca. On some
1281 systems, alloca is implemented in terms of malloc, and if we're
1282 using the relocating allocator routines, then malloc could cause a
1283 relocation, which might (if the strings being searched are in the
1284 ralloc heap) shift the data out from underneath the regexp
1285 routines.
1286
1287 Here's another reason to avoid allocation: Emacs
1288 processes input from X in a signal handler; processing X input may
1289 call malloc; if input arrives while a matching routine is calling
1290 malloc, then we're scrod. But Emacs can't just block input while
1291 calling matching routines; then we don't notice interrupts when
1292 they come in. So, Emacs blocks input around all regexp calls
1293 except the matching calls, which it leaves unprotected, in the
1294 faith that they will not malloc. */
1295
1296 /* Normally, this is fine. */
1297 #define MATCH_MAY_ALLOCATE
1298
1299 /* When using GNU C, we are not REALLY using the C alloca, no matter
1300 what config.h may say. So don't take precautions for it. */
1301 #ifdef __GNUC__
1302 # undef C_ALLOCA
1303 #endif
1304
1305 /* The match routines may not allocate if (1) they would do it with malloc
1306 and (2) it's not safe for them to use malloc.
1307 Note that if REL_ALLOC is defined, matching would not use malloc for the
1308 failure stack, but we would still use it for the register vectors;
1309 so REL_ALLOC should not affect this. */
1310 #if (defined C_ALLOCA || defined REGEX_MALLOC) && defined emacs
1311 # undef MATCH_MAY_ALLOCATE
1312 #endif
1313
1314 \f
1315 /* Failure stack declarations and macros; both re_compile_fastmap and
1316 re_match_2 use a failure stack. These have to be macros because of
1317 REGEX_ALLOCATE_STACK. */
1318
1319
1320 /* Approximate number of failure points for which to initially allocate space
1321 when matching. If this number is exceeded, we allocate more
1322 space, so it is not a hard limit. */
1323 #ifndef INIT_FAILURE_ALLOC
1324 # define INIT_FAILURE_ALLOC 20
1325 #endif
1326
1327 /* Roughly the maximum number of failure points on the stack. Would be
1328 exactly that if always used TYPICAL_FAILURE_SIZE items each time we failed.
1329 This is a variable only so users of regex can assign to it; we never
1330 change it ourselves. */
1331 # if defined MATCH_MAY_ALLOCATE
1332 /* Note that 4400 was enough to cause a crash on Alpha OSF/1,
1333 whose default stack limit is 2mb. In order for a larger
1334 value to work reliably, you have to try to make it accord
1335 with the process stack limit. */
1336 size_t re_max_failures = 40000;
1337 # else
1338 size_t re_max_failures = 4000;
1339 # endif
1340
1341 union fail_stack_elt
1342 {
1343 re_char *pointer;
1344 /* This should be the biggest `int' that's no bigger than a pointer. */
1345 long integer;
1346 };
1347
1348 typedef union fail_stack_elt fail_stack_elt_t;
1349
1350 typedef struct
1351 {
1352 fail_stack_elt_t *stack;
1353 size_t size;
1354 size_t avail; /* Offset of next open position. */
1355 size_t frame; /* Offset of the cur constructed frame. */
1356 } fail_stack_type;
1357
1358 #define FAIL_STACK_EMPTY() (fail_stack.frame == 0)
1359 #define FAIL_STACK_FULL() (fail_stack.avail == fail_stack.size)
1360
1361
1362 /* Define macros to initialize and free the failure stack.
1363 Do `return -2' if the alloc fails. */
1364
1365 #ifdef MATCH_MAY_ALLOCATE
1366 # define INIT_FAIL_STACK() \
1367 do { \
1368 fail_stack.stack = (fail_stack_elt_t *) \
1369 REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * TYPICAL_FAILURE_SIZE \
1370 * sizeof (fail_stack_elt_t)); \
1371 \
1372 if (fail_stack.stack == NULL) \
1373 return -2; \
1374 \
1375 fail_stack.size = INIT_FAILURE_ALLOC; \
1376 fail_stack.avail = 0; \
1377 fail_stack.frame = 0; \
1378 } while (0)
1379
1380 # define RESET_FAIL_STACK() REGEX_FREE_STACK (fail_stack.stack)
1381 #else
1382 # define INIT_FAIL_STACK() \
1383 do { \
1384 fail_stack.avail = 0; \
1385 fail_stack.frame = 0; \
1386 } while (0)
1387
1388 # define RESET_FAIL_STACK() ((void)0)
1389 #endif
1390
1391
1392 /* Double the size of FAIL_STACK, up to a limit
1393 which allows approximately `re_max_failures' items.
1394
1395 Return 1 if succeeds, and 0 if either ran out of memory
1396 allocating space for it or it was already too large.
1397
1398 REGEX_REALLOCATE_STACK requires `destination' be declared. */
1399
1400 /* Factor to increase the failure stack size by
1401 when we increase it.
1402 This used to be 2, but 2 was too wasteful
1403 because the old discarded stacks added up to as much space
1404 were as ultimate, maximum-size stack. */
1405 #define FAIL_STACK_GROWTH_FACTOR 4
1406
1407 #define GROW_FAIL_STACK(fail_stack) \
1408 (((fail_stack).size * sizeof (fail_stack_elt_t) \
1409 >= re_max_failures * TYPICAL_FAILURE_SIZE) \
1410 ? 0 \
1411 : ((fail_stack).stack \
1412 = (fail_stack_elt_t *) \
1413 REGEX_REALLOCATE_STACK ((fail_stack).stack, \
1414 (fail_stack).size * sizeof (fail_stack_elt_t), \
1415 MIN (re_max_failures * TYPICAL_FAILURE_SIZE, \
1416 ((fail_stack).size * sizeof (fail_stack_elt_t) \
1417 * FAIL_STACK_GROWTH_FACTOR))), \
1418 \
1419 (fail_stack).stack == NULL \
1420 ? 0 \
1421 : ((fail_stack).size \
1422 = (MIN (re_max_failures * TYPICAL_FAILURE_SIZE, \
1423 ((fail_stack).size * sizeof (fail_stack_elt_t) \
1424 * FAIL_STACK_GROWTH_FACTOR)) \
1425 / sizeof (fail_stack_elt_t)), \
1426 1)))
1427
1428
1429 /* Push a pointer value onto the failure stack.
1430 Assumes the variable `fail_stack'. Probably should only
1431 be called from within `PUSH_FAILURE_POINT'. */
1432 #define PUSH_FAILURE_POINTER(item) \
1433 fail_stack.stack[fail_stack.avail++].pointer = (item)
1434
1435 /* This pushes an integer-valued item onto the failure stack.
1436 Assumes the variable `fail_stack'. Probably should only
1437 be called from within `PUSH_FAILURE_POINT'. */
1438 #define PUSH_FAILURE_INT(item) \
1439 fail_stack.stack[fail_stack.avail++].integer = (item)
1440
1441 /* Push a fail_stack_elt_t value onto the failure stack.
1442 Assumes the variable `fail_stack'. Probably should only
1443 be called from within `PUSH_FAILURE_POINT'. */
1444 #define PUSH_FAILURE_ELT(item) \
1445 fail_stack.stack[fail_stack.avail++] = (item)
1446
1447 /* These three POP... operations complement the three PUSH... operations.
1448 All assume that `fail_stack' is nonempty. */
1449 #define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
1450 #define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
1451 #define POP_FAILURE_ELT() fail_stack.stack[--fail_stack.avail]
1452
1453 /* Individual items aside from the registers. */
1454 #define NUM_NONREG_ITEMS 3
1455
1456 /* Used to examine the stack (to detect infinite loops). */
1457 #define FAILURE_PAT(h) fail_stack.stack[(h) - 1].pointer
1458 #define FAILURE_STR(h) (fail_stack.stack[(h) - 2].pointer)
1459 #define NEXT_FAILURE_HANDLE(h) fail_stack.stack[(h) - 3].integer
1460 #define TOP_FAILURE_HANDLE() fail_stack.frame
1461
1462
1463 #define ENSURE_FAIL_STACK(space) \
1464 while (REMAINING_AVAIL_SLOTS <= space) { \
1465 if (!GROW_FAIL_STACK (fail_stack)) \
1466 return -2; \
1467 DEBUG_PRINT2 ("\n Doubled stack; size now: %d\n", (fail_stack).size);\
1468 DEBUG_PRINT2 (" slots available: %d\n", REMAINING_AVAIL_SLOTS);\
1469 }
1470
1471 /* Push register NUM onto the stack. */
1472 #define PUSH_FAILURE_REG(num) \
1473 do { \
1474 char *destination; \
1475 ENSURE_FAIL_STACK(3); \
1476 DEBUG_PRINT4 (" Push reg %d (spanning %p -> %p)\n", \
1477 num, regstart[num], regend[num]); \
1478 PUSH_FAILURE_POINTER (regstart[num]); \
1479 PUSH_FAILURE_POINTER (regend[num]); \
1480 PUSH_FAILURE_INT (num); \
1481 } while (0)
1482
1483 /* Change the counter's value to VAL, but make sure that it will
1484 be reset when backtracking. */
1485 #define PUSH_NUMBER(ptr,val) \
1486 do { \
1487 char *destination; \
1488 int c; \
1489 ENSURE_FAIL_STACK(3); \
1490 EXTRACT_NUMBER (c, ptr); \
1491 DEBUG_PRINT4 (" Push number %p = %d -> %d\n", ptr, c, val); \
1492 PUSH_FAILURE_INT (c); \
1493 PUSH_FAILURE_POINTER (ptr); \
1494 PUSH_FAILURE_INT (-1); \
1495 STORE_NUMBER (ptr, val); \
1496 } while (0)
1497
1498 /* Pop a saved register off the stack. */
1499 #define POP_FAILURE_REG_OR_COUNT() \
1500 do { \
1501 int reg = POP_FAILURE_INT (); \
1502 if (reg == -1) \
1503 { \
1504 /* It's a counter. */ \
1505 /* Here, we discard `const', making re_match non-reentrant. */ \
1506 unsigned char *ptr = (unsigned char*) POP_FAILURE_POINTER (); \
1507 reg = POP_FAILURE_INT (); \
1508 STORE_NUMBER (ptr, reg); \
1509 DEBUG_PRINT3 (" Pop counter %p = %d\n", ptr, reg); \
1510 } \
1511 else \
1512 { \
1513 regend[reg] = POP_FAILURE_POINTER (); \
1514 regstart[reg] = POP_FAILURE_POINTER (); \
1515 DEBUG_PRINT4 (" Pop reg %d (spanning %p -> %p)\n", \
1516 reg, regstart[reg], regend[reg]); \
1517 } \
1518 } while (0)
1519
1520 /* Check that we are not stuck in an infinite loop. */
1521 #define CHECK_INFINITE_LOOP(pat_cur, string_place) \
1522 do { \
1523 int failure = TOP_FAILURE_HANDLE(); \
1524 /* Check for infinite matching loops */ \
1525 while (failure > 0 && \
1526 (FAILURE_STR (failure) == string_place \
1527 || FAILURE_STR (failure) == NULL)) \
1528 { \
1529 assert (FAILURE_PAT (failure) >= bufp->buffer \
1530 && FAILURE_PAT (failure) <= bufp->buffer + bufp->used); \
1531 if (FAILURE_PAT (failure) == pat_cur) \
1532 goto fail; \
1533 DEBUG_PRINT2 (" Other pattern: %p\n", FAILURE_PAT (failure)); \
1534 failure = NEXT_FAILURE_HANDLE(failure); \
1535 } \
1536 DEBUG_PRINT2 (" Other string: %p\n", FAILURE_STR (failure)); \
1537 } while (0)
1538
1539 /* Push the information about the state we will need
1540 if we ever fail back to it.
1541
1542 Requires variables fail_stack, regstart, regend and
1543 num_regs be declared. GROW_FAIL_STACK requires `destination' be
1544 declared.
1545
1546 Does `return FAILURE_CODE' if runs out of memory. */
1547
1548 #define PUSH_FAILURE_POINT(pattern, string_place) \
1549 do { \
1550 char *destination; \
1551 /* Must be int, so when we don't save any registers, the arithmetic \
1552 of 0 + -1 isn't done as unsigned. */ \
1553 \
1554 DEBUG_STATEMENT (nfailure_points_pushed++); \
1555 DEBUG_PRINT1 ("\nPUSH_FAILURE_POINT:\n"); \
1556 DEBUG_PRINT2 (" Before push, next avail: %d\n", (fail_stack).avail); \
1557 DEBUG_PRINT2 (" size: %d\n", (fail_stack).size);\
1558 \
1559 ENSURE_FAIL_STACK (NUM_NONREG_ITEMS); \
1560 \
1561 DEBUG_PRINT1 ("\n"); \
1562 \
1563 DEBUG_PRINT2 (" Push frame index: %d\n", fail_stack.frame); \
1564 PUSH_FAILURE_INT (fail_stack.frame); \
1565 \
1566 DEBUG_PRINT2 (" Push string %p: `", string_place); \
1567 DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2, size2);\
1568 DEBUG_PRINT1 ("'\n"); \
1569 PUSH_FAILURE_POINTER (string_place); \
1570 \
1571 DEBUG_PRINT2 (" Push pattern %p: ", pattern); \
1572 DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern, pend); \
1573 PUSH_FAILURE_POINTER (pattern); \
1574 \
1575 /* Close the frame by moving the frame pointer past it. */ \
1576 fail_stack.frame = fail_stack.avail; \
1577 } while (0)
1578
1579 /* Estimate the size of data pushed by a typical failure stack entry.
1580 An estimate is all we need, because all we use this for
1581 is to choose a limit for how big to make the failure stack. */
1582
1583 #define TYPICAL_FAILURE_SIZE 20
1584
1585 /* How many items can still be added to the stack without overflowing it. */
1586 #define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
1587
1588
1589 /* Pops what PUSH_FAIL_STACK pushes.
1590
1591 We restore into the parameters, all of which should be lvalues:
1592 STR -- the saved data position.
1593 PAT -- the saved pattern position.
1594 REGSTART, REGEND -- arrays of string positions.
1595
1596 Also assumes the variables `fail_stack' and (if debugging), `bufp',
1597 `pend', `string1', `size1', `string2', and `size2'. */
1598
1599 #define POP_FAILURE_POINT(str, pat) \
1600 do { \
1601 assert (!FAIL_STACK_EMPTY ()); \
1602 \
1603 /* Remove failure points and point to how many regs pushed. */ \
1604 DEBUG_PRINT1 ("POP_FAILURE_POINT:\n"); \
1605 DEBUG_PRINT2 (" Before pop, next avail: %d\n", fail_stack.avail); \
1606 DEBUG_PRINT2 (" size: %d\n", fail_stack.size); \
1607 \
1608 /* Pop the saved registers. */ \
1609 while (fail_stack.frame < fail_stack.avail) \
1610 POP_FAILURE_REG_OR_COUNT (); \
1611 \
1612 pat = POP_FAILURE_POINTER (); \
1613 DEBUG_PRINT2 (" Popping pattern %p: ", pat); \
1614 DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend); \
1615 \
1616 /* If the saved string location is NULL, it came from an \
1617 on_failure_keep_string_jump opcode, and we want to throw away the \
1618 saved NULL, thus retaining our current position in the string. */ \
1619 str = POP_FAILURE_POINTER (); \
1620 DEBUG_PRINT2 (" Popping string %p: `", str); \
1621 DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2); \
1622 DEBUG_PRINT1 ("'\n"); \
1623 \
1624 fail_stack.frame = POP_FAILURE_INT (); \
1625 DEBUG_PRINT2 (" Popping frame index: %d\n", fail_stack.frame); \
1626 \
1627 assert (fail_stack.avail >= 0); \
1628 assert (fail_stack.frame <= fail_stack.avail); \
1629 \
1630 DEBUG_STATEMENT (nfailure_points_popped++); \
1631 } while (0) /* POP_FAILURE_POINT */
1632
1633
1634 \f
1635 /* Registers are set to a sentinel when they haven't yet matched. */
1636 #define REG_UNSET(e) ((e) == NULL)
1637 \f
1638 /* Subroutine declarations and macros for regex_compile. */
1639
1640 static reg_errcode_t regex_compile _RE_ARGS ((re_char *pattern, size_t size,
1641 reg_syntax_t syntax,
1642 struct re_pattern_buffer *bufp));
1643 static void store_op1 _RE_ARGS ((re_opcode_t op, unsigned char *loc, int arg));
1644 static void store_op2 _RE_ARGS ((re_opcode_t op, unsigned char *loc,
1645 int arg1, int arg2));
1646 static void insert_op1 _RE_ARGS ((re_opcode_t op, unsigned char *loc,
1647 int arg, unsigned char *end));
1648 static void insert_op2 _RE_ARGS ((re_opcode_t op, unsigned char *loc,
1649 int arg1, int arg2, unsigned char *end));
1650 static boolean at_begline_loc_p _RE_ARGS ((re_char *pattern,
1651 re_char *p,
1652 reg_syntax_t syntax));
1653 static boolean at_endline_loc_p _RE_ARGS ((re_char *p,
1654 re_char *pend,
1655 reg_syntax_t syntax));
1656 static re_char *skip_one_char _RE_ARGS ((re_char *p));
1657 static int analyse_first _RE_ARGS ((re_char *p, re_char *pend,
1658 char *fastmap, const int multibyte));
1659
1660 /* Fetch the next character in the uncompiled pattern---translating it
1661 if necessary. */
1662 #define PATFETCH(c) \
1663 do { \
1664 PATFETCH_RAW (c); \
1665 c = TRANSLATE (c); \
1666 } while (0)
1667
1668 /* Fetch the next character in the uncompiled pattern, with no
1669 translation. */
1670 #define PATFETCH_RAW(c) \
1671 do { \
1672 int len; \
1673 if (p == pend) return REG_EEND; \
1674 c = RE_STRING_CHAR_AND_LENGTH (p, pend - p, len); \
1675 p += len; \
1676 } while (0)
1677
1678
1679 /* If `translate' is non-null, return translate[D], else just D. We
1680 cast the subscript to translate because some data is declared as
1681 `char *', to avoid warnings when a string constant is passed. But
1682 when we use a character as a subscript we must make it unsigned. */
1683 #ifndef TRANSLATE
1684 # define TRANSLATE(d) \
1685 (RE_TRANSLATE_P (translate) ? RE_TRANSLATE (translate, (d)) : (d))
1686 #endif
1687
1688
1689 /* Macros for outputting the compiled pattern into `buffer'. */
1690
1691 /* If the buffer isn't allocated when it comes in, use this. */
1692 #define INIT_BUF_SIZE 32
1693
1694 /* Make sure we have at least N more bytes of space in buffer. */
1695 #define GET_BUFFER_SPACE(n) \
1696 while ((size_t) (b - bufp->buffer + (n)) > bufp->allocated) \
1697 EXTEND_BUFFER ()
1698
1699 /* Make sure we have one more byte of buffer space and then add C to it. */
1700 #define BUF_PUSH(c) \
1701 do { \
1702 GET_BUFFER_SPACE (1); \
1703 *b++ = (unsigned char) (c); \
1704 } while (0)
1705
1706
1707 /* Ensure we have two more bytes of buffer space and then append C1 and C2. */
1708 #define BUF_PUSH_2(c1, c2) \
1709 do { \
1710 GET_BUFFER_SPACE (2); \
1711 *b++ = (unsigned char) (c1); \
1712 *b++ = (unsigned char) (c2); \
1713 } while (0)
1714
1715
1716 /* As with BUF_PUSH_2, except for three bytes. */
1717 #define BUF_PUSH_3(c1, c2, c3) \
1718 do { \
1719 GET_BUFFER_SPACE (3); \
1720 *b++ = (unsigned char) (c1); \
1721 *b++ = (unsigned char) (c2); \
1722 *b++ = (unsigned char) (c3); \
1723 } while (0)
1724
1725
1726 /* Store a jump with opcode OP at LOC to location TO. We store a
1727 relative address offset by the three bytes the jump itself occupies. */
1728 #define STORE_JUMP(op, loc, to) \
1729 store_op1 (op, loc, (to) - (loc) - 3)
1730
1731 /* Likewise, for a two-argument jump. */
1732 #define STORE_JUMP2(op, loc, to, arg) \
1733 store_op2 (op, loc, (to) - (loc) - 3, arg)
1734
1735 /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
1736 #define INSERT_JUMP(op, loc, to) \
1737 insert_op1 (op, loc, (to) - (loc) - 3, b)
1738
1739 /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
1740 #define INSERT_JUMP2(op, loc, to, arg) \
1741 insert_op2 (op, loc, (to) - (loc) - 3, arg, b)
1742
1743
1744 /* This is not an arbitrary limit: the arguments which represent offsets
1745 into the pattern are two bytes long. So if 2^16 bytes turns out to
1746 be too small, many things would have to change. */
1747 /* Any other compiler which, like MSC, has allocation limit below 2^16
1748 bytes will have to use approach similar to what was done below for
1749 MSC and drop MAX_BUF_SIZE a bit. Otherwise you may end up
1750 reallocating to 0 bytes. Such thing is not going to work too well.
1751 You have been warned!! */
1752 #if defined _MSC_VER && !defined WIN32
1753 /* Microsoft C 16-bit versions limit malloc to approx 65512 bytes. */
1754 # define MAX_BUF_SIZE 65500L
1755 #else
1756 # define MAX_BUF_SIZE (1L << 16)
1757 #endif
1758
1759 /* Extend the buffer by twice its current size via realloc and
1760 reset the pointers that pointed into the old block to point to the
1761 correct places in the new one. If extending the buffer results in it
1762 being larger than MAX_BUF_SIZE, then flag memory exhausted. */
1763 #if __BOUNDED_POINTERS__
1764 # define SET_HIGH_BOUND(P) (__ptrhigh (P) = __ptrlow (P) + bufp->allocated)
1765 # define MOVE_BUFFER_POINTER(P) \
1766 (__ptrlow (P) += incr, SET_HIGH_BOUND (P), __ptrvalue (P) += incr)
1767 # define ELSE_EXTEND_BUFFER_HIGH_BOUND \
1768 else \
1769 { \
1770 SET_HIGH_BOUND (b); \
1771 SET_HIGH_BOUND (begalt); \
1772 if (fixup_alt_jump) \
1773 SET_HIGH_BOUND (fixup_alt_jump); \
1774 if (laststart) \
1775 SET_HIGH_BOUND (laststart); \
1776 if (pending_exact) \
1777 SET_HIGH_BOUND (pending_exact); \
1778 }
1779 #else
1780 # define MOVE_BUFFER_POINTER(P) (P) += incr
1781 # define ELSE_EXTEND_BUFFER_HIGH_BOUND
1782 #endif
1783 #define EXTEND_BUFFER() \
1784 do { \
1785 re_char *old_buffer = bufp->buffer; \
1786 if (bufp->allocated == MAX_BUF_SIZE) \
1787 return REG_ESIZE; \
1788 bufp->allocated <<= 1; \
1789 if (bufp->allocated > MAX_BUF_SIZE) \
1790 bufp->allocated = MAX_BUF_SIZE; \
1791 RETALLOC (bufp->buffer, bufp->allocated, unsigned char); \
1792 if (bufp->buffer == NULL) \
1793 return REG_ESPACE; \
1794 /* If the buffer moved, move all the pointers into it. */ \
1795 if (old_buffer != bufp->buffer) \
1796 { \
1797 int incr = bufp->buffer - old_buffer; \
1798 MOVE_BUFFER_POINTER (b); \
1799 MOVE_BUFFER_POINTER (begalt); \
1800 if (fixup_alt_jump) \
1801 MOVE_BUFFER_POINTER (fixup_alt_jump); \
1802 if (laststart) \
1803 MOVE_BUFFER_POINTER (laststart); \
1804 if (pending_exact) \
1805 MOVE_BUFFER_POINTER (pending_exact); \
1806 } \
1807 ELSE_EXTEND_BUFFER_HIGH_BOUND \
1808 } while (0)
1809
1810
1811 /* Since we have one byte reserved for the register number argument to
1812 {start,stop}_memory, the maximum number of groups we can report
1813 things about is what fits in that byte. */
1814 #define MAX_REGNUM 255
1815
1816 /* But patterns can have more than `MAX_REGNUM' registers. We just
1817 ignore the excess. */
1818 typedef unsigned regnum_t;
1819
1820
1821 /* Macros for the compile stack. */
1822
1823 /* Since offsets can go either forwards or backwards, this type needs to
1824 be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
1825 /* int may be not enough when sizeof(int) == 2. */
1826 typedef long pattern_offset_t;
1827
1828 typedef struct
1829 {
1830 pattern_offset_t begalt_offset;
1831 pattern_offset_t fixup_alt_jump;
1832 pattern_offset_t laststart_offset;
1833 regnum_t regnum;
1834 } compile_stack_elt_t;
1835
1836
1837 typedef struct
1838 {
1839 compile_stack_elt_t *stack;
1840 unsigned size;
1841 unsigned avail; /* Offset of next open position. */
1842 } compile_stack_type;
1843
1844
1845 #define INIT_COMPILE_STACK_SIZE 32
1846
1847 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
1848 #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
1849
1850 /* The next available element. */
1851 #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
1852
1853
1854 /* Structure to manage work area for range table. */
1855 struct range_table_work_area
1856 {
1857 int *table; /* actual work area. */
1858 int allocated; /* allocated size for work area in bytes. */
1859 int used; /* actually used size in words. */
1860 int bits; /* flag to record character classes */
1861 };
1862
1863 /* Make sure that WORK_AREA can hold more N multibyte characters. */
1864 #define EXTEND_RANGE_TABLE_WORK_AREA(work_area, n) \
1865 do { \
1866 if (((work_area).used + (n)) * sizeof (int) > (work_area).allocated) \
1867 { \
1868 (work_area).allocated += 16 * sizeof (int); \
1869 if ((work_area).table) \
1870 (work_area).table \
1871 = (int *) realloc ((work_area).table, (work_area).allocated); \
1872 else \
1873 (work_area).table \
1874 = (int *) malloc ((work_area).allocated); \
1875 if ((work_area).table == 0) \
1876 FREE_STACK_RETURN (REG_ESPACE); \
1877 } \
1878 } while (0)
1879
1880 #define SET_RANGE_TABLE_WORK_AREA_BIT(work_area, bit) \
1881 (work_area).bits |= (bit)
1882
1883 /* Bits used to implement the multibyte-part of the various character classes
1884 such as [:alnum:] in a charset's range table. */
1885 #define BIT_WORD 0x1
1886 #define BIT_LOWER 0x2
1887 #define BIT_PUNCT 0x4
1888 #define BIT_SPACE 0x8
1889 #define BIT_UPPER 0x10
1890 #define BIT_MULTIBYTE 0x20
1891
1892 /* Set a range (RANGE_START, RANGE_END) to WORK_AREA. */
1893 #define SET_RANGE_TABLE_WORK_AREA(work_area, range_start, range_end) \
1894 do { \
1895 EXTEND_RANGE_TABLE_WORK_AREA ((work_area), 2); \
1896 (work_area).table[(work_area).used++] = (range_start); \
1897 (work_area).table[(work_area).used++] = (range_end); \
1898 } while (0)
1899
1900 /* Free allocated memory for WORK_AREA. */
1901 #define FREE_RANGE_TABLE_WORK_AREA(work_area) \
1902 do { \
1903 if ((work_area).table) \
1904 free ((work_area).table); \
1905 } while (0)
1906
1907 #define CLEAR_RANGE_TABLE_WORK_USED(work_area) ((work_area).used = 0, (work_area).bits = 0)
1908 #define RANGE_TABLE_WORK_USED(work_area) ((work_area).used)
1909 #define RANGE_TABLE_WORK_BITS(work_area) ((work_area).bits)
1910 #define RANGE_TABLE_WORK_ELT(work_area, i) ((work_area).table[i])
1911
1912
1913 /* Set the bit for character C in a list. */
1914 #define SET_LIST_BIT(c) (b[((c)) / BYTEWIDTH] |= 1 << ((c) % BYTEWIDTH))
1915
1916
1917 /* Get the next unsigned number in the uncompiled pattern. */
1918 #define GET_UNSIGNED_NUMBER(num) \
1919 do { if (p != pend) \
1920 { \
1921 PATFETCH (c); \
1922 while ('0' <= c && c <= '9') \
1923 { \
1924 if (num < 0) \
1925 num = 0; \
1926 num = num * 10 + c - '0'; \
1927 if (p == pend) \
1928 break; \
1929 PATFETCH (c); \
1930 } \
1931 } \
1932 } while (0)
1933
1934 #if WIDE_CHAR_SUPPORT
1935 /* The GNU C library provides support for user-defined character classes
1936 and the functions from ISO C amendement 1. */
1937 # ifdef CHARCLASS_NAME_MAX
1938 # define CHAR_CLASS_MAX_LENGTH CHARCLASS_NAME_MAX
1939 # else
1940 /* This shouldn't happen but some implementation might still have this
1941 problem. Use a reasonable default value. */
1942 # define CHAR_CLASS_MAX_LENGTH 256
1943 # endif
1944 typedef wctype_t re_wctype_t;
1945 typedef wchar_t re_wchar_t;
1946 # define re_wctype wctype
1947 # define re_iswctype iswctype
1948 # define re_wctype_to_bit(cc) 0
1949 #else
1950 # define CHAR_CLASS_MAX_LENGTH 9 /* Namely, `multibyte'. */
1951 # define btowc(c) c
1952
1953 /* Character classes. */
1954 typedef enum { RECC_ERROR = 0,
1955 RECC_ALNUM, RECC_ALPHA, RECC_WORD,
1956 RECC_GRAPH, RECC_PRINT,
1957 RECC_LOWER, RECC_UPPER,
1958 RECC_PUNCT, RECC_CNTRL,
1959 RECC_DIGIT, RECC_XDIGIT,
1960 RECC_BLANK, RECC_SPACE,
1961 RECC_MULTIBYTE, RECC_NONASCII,
1962 RECC_ASCII, RECC_UNIBYTE
1963 } re_wctype_t;
1964
1965 typedef int re_wchar_t;
1966
1967 /* Map a string to the char class it names (if any). */
1968 static re_wctype_t
1969 re_wctype (string)
1970 re_char *string;
1971 {
1972 if (STREQ (string, "alnum")) return RECC_ALNUM;
1973 else if (STREQ (string, "alpha")) return RECC_ALPHA;
1974 else if (STREQ (string, "word")) return RECC_WORD;
1975 else if (STREQ (string, "ascii")) return RECC_ASCII;
1976 else if (STREQ (string, "nonascii")) return RECC_NONASCII;
1977 else if (STREQ (string, "graph")) return RECC_GRAPH;
1978 else if (STREQ (string, "lower")) return RECC_LOWER;
1979 else if (STREQ (string, "print")) return RECC_PRINT;
1980 else if (STREQ (string, "punct")) return RECC_PUNCT;
1981 else if (STREQ (string, "space")) return RECC_SPACE;
1982 else if (STREQ (string, "upper")) return RECC_UPPER;
1983 else if (STREQ (string, "unibyte")) return RECC_UNIBYTE;
1984 else if (STREQ (string, "multibyte")) return RECC_MULTIBYTE;
1985 else if (STREQ (string, "digit")) return RECC_DIGIT;
1986 else if (STREQ (string, "xdigit")) return RECC_XDIGIT;
1987 else if (STREQ (string, "cntrl")) return RECC_CNTRL;
1988 else if (STREQ (string, "blank")) return RECC_BLANK;
1989 else return 0;
1990 }
1991
1992 /* True iff CH is in the char class CC. */
1993 static boolean
1994 re_iswctype (ch, cc)
1995 int ch;
1996 re_wctype_t cc;
1997 {
1998 switch (cc)
1999 {
2000 case RECC_ALNUM: return ISALNUM (ch);
2001 case RECC_ALPHA: return ISALPHA (ch);
2002 case RECC_BLANK: return ISBLANK (ch);
2003 case RECC_CNTRL: return ISCNTRL (ch);
2004 case RECC_DIGIT: return ISDIGIT (ch);
2005 case RECC_GRAPH: return ISGRAPH (ch);
2006 case RECC_LOWER: return ISLOWER (ch);
2007 case RECC_PRINT: return ISPRINT (ch);
2008 case RECC_PUNCT: return ISPUNCT (ch);
2009 case RECC_SPACE: return ISSPACE (ch);
2010 case RECC_UPPER: return ISUPPER (ch);
2011 case RECC_XDIGIT: return ISXDIGIT (ch);
2012 case RECC_ASCII: return IS_REAL_ASCII (ch);
2013 case RECC_NONASCII: return !IS_REAL_ASCII (ch);
2014 case RECC_UNIBYTE: return ISUNIBYTE (ch);
2015 case RECC_MULTIBYTE: return !ISUNIBYTE (ch);
2016 case RECC_WORD: return ISWORD (ch);
2017 case RECC_ERROR: return false;
2018 default:
2019 abort();
2020 }
2021 }
2022
2023 /* Return a bit-pattern to use in the range-table bits to match multibyte
2024 chars of class CC. */
2025 static int
2026 re_wctype_to_bit (cc)
2027 re_wctype_t cc;
2028 {
2029 switch (cc)
2030 {
2031 case RECC_NONASCII: case RECC_PRINT: case RECC_GRAPH:
2032 case RECC_MULTIBYTE: return BIT_MULTIBYTE;
2033 case RECC_ALPHA: case RECC_ALNUM: case RECC_WORD: return BIT_WORD;
2034 case RECC_LOWER: return BIT_LOWER;
2035 case RECC_UPPER: return BIT_UPPER;
2036 case RECC_PUNCT: return BIT_PUNCT;
2037 case RECC_SPACE: return BIT_SPACE;
2038 case RECC_ASCII: case RECC_DIGIT: case RECC_XDIGIT: case RECC_CNTRL:
2039 case RECC_BLANK: case RECC_UNIBYTE: case RECC_ERROR: return 0;
2040 default:
2041 abort();
2042 }
2043 }
2044 #endif
2045
2046 /* Explicit quit checking is only used on NTemacs. */
2047 #if defined WINDOWSNT && defined emacs && defined QUIT
2048 extern int immediate_quit;
2049 # define IMMEDIATE_QUIT_CHECK \
2050 do { \
2051 if (immediate_quit) QUIT; \
2052 } while (0)
2053 #else
2054 # define IMMEDIATE_QUIT_CHECK ((void)0)
2055 #endif
2056 \f
2057 #ifndef MATCH_MAY_ALLOCATE
2058
2059 /* If we cannot allocate large objects within re_match_2_internal,
2060 we make the fail stack and register vectors global.
2061 The fail stack, we grow to the maximum size when a regexp
2062 is compiled.
2063 The register vectors, we adjust in size each time we
2064 compile a regexp, according to the number of registers it needs. */
2065
2066 static fail_stack_type fail_stack;
2067
2068 /* Size with which the following vectors are currently allocated.
2069 That is so we can make them bigger as needed,
2070 but never make them smaller. */
2071 static int regs_allocated_size;
2072
2073 static re_char ** regstart, ** regend;
2074 static re_char **best_regstart, **best_regend;
2075
2076 /* Make the register vectors big enough for NUM_REGS registers,
2077 but don't make them smaller. */
2078
2079 static
2080 regex_grow_registers (num_regs)
2081 int num_regs;
2082 {
2083 if (num_regs > regs_allocated_size)
2084 {
2085 RETALLOC_IF (regstart, num_regs, re_char *);
2086 RETALLOC_IF (regend, num_regs, re_char *);
2087 RETALLOC_IF (best_regstart, num_regs, re_char *);
2088 RETALLOC_IF (best_regend, num_regs, re_char *);
2089
2090 regs_allocated_size = num_regs;
2091 }
2092 }
2093
2094 #endif /* not MATCH_MAY_ALLOCATE */
2095 \f
2096 static boolean group_in_compile_stack _RE_ARGS ((compile_stack_type
2097 compile_stack,
2098 regnum_t regnum));
2099
2100 /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
2101 Returns one of error codes defined in `regex.h', or zero for success.
2102
2103 Assumes the `allocated' (and perhaps `buffer') and `translate'
2104 fields are set in BUFP on entry.
2105
2106 If it succeeds, results are put in BUFP (if it returns an error, the
2107 contents of BUFP are undefined):
2108 `buffer' is the compiled pattern;
2109 `syntax' is set to SYNTAX;
2110 `used' is set to the length of the compiled pattern;
2111 `fastmap_accurate' is zero;
2112 `re_nsub' is the number of subexpressions in PATTERN;
2113 `not_bol' and `not_eol' are zero;
2114
2115 The `fastmap' field is neither examined nor set. */
2116
2117 /* Insert the `jump' from the end of last alternative to "here".
2118 The space for the jump has already been allocated. */
2119 #define FIXUP_ALT_JUMP() \
2120 do { \
2121 if (fixup_alt_jump) \
2122 STORE_JUMP (jump, fixup_alt_jump, b); \
2123 } while (0)
2124
2125
2126 /* Return, freeing storage we allocated. */
2127 #define FREE_STACK_RETURN(value) \
2128 do { \
2129 FREE_RANGE_TABLE_WORK_AREA (range_table_work); \
2130 free (compile_stack.stack); \
2131 return value; \
2132 } while (0)
2133
2134 static reg_errcode_t
2135 regex_compile (pattern, size, syntax, bufp)
2136 re_char *pattern;
2137 size_t size;
2138 reg_syntax_t syntax;
2139 struct re_pattern_buffer *bufp;
2140 {
2141 /* We fetch characters from PATTERN here. */
2142 register re_wchar_t c, c1;
2143
2144 /* A random temporary spot in PATTERN. */
2145 re_char *p1;
2146
2147 /* Points to the end of the buffer, where we should append. */
2148 register unsigned char *b;
2149
2150 /* Keeps track of unclosed groups. */
2151 compile_stack_type compile_stack;
2152
2153 /* Points to the current (ending) position in the pattern. */
2154 #ifdef AIX
2155 /* `const' makes AIX compiler fail. */
2156 unsigned char *p = pattern;
2157 #else
2158 re_char *p = pattern;
2159 #endif
2160 re_char *pend = pattern + size;
2161
2162 /* How to translate the characters in the pattern. */
2163 RE_TRANSLATE_TYPE translate = bufp->translate;
2164
2165 /* Address of the count-byte of the most recently inserted `exactn'
2166 command. This makes it possible to tell if a new exact-match
2167 character can be added to that command or if the character requires
2168 a new `exactn' command. */
2169 unsigned char *pending_exact = 0;
2170
2171 /* Address of start of the most recently finished expression.
2172 This tells, e.g., postfix * where to find the start of its
2173 operand. Reset at the beginning of groups and alternatives. */
2174 unsigned char *laststart = 0;
2175
2176 /* Address of beginning of regexp, or inside of last group. */
2177 unsigned char *begalt;
2178
2179 /* Place in the uncompiled pattern (i.e., the {) to
2180 which to go back if the interval is invalid. */
2181 re_char *beg_interval;
2182
2183 /* Address of the place where a forward jump should go to the end of
2184 the containing expression. Each alternative of an `or' -- except the
2185 last -- ends with a forward jump of this sort. */
2186 unsigned char *fixup_alt_jump = 0;
2187
2188 /* Counts open-groups as they are encountered. Remembered for the
2189 matching close-group on the compile stack, so the same register
2190 number is put in the stop_memory as the start_memory. */
2191 regnum_t regnum = 0;
2192
2193 /* Work area for range table of charset. */
2194 struct range_table_work_area range_table_work;
2195
2196 /* If the object matched can contain multibyte characters. */
2197 const boolean multibyte = RE_MULTIBYTE_P (bufp);
2198
2199 #ifdef DEBUG
2200 debug++;
2201 DEBUG_PRINT1 ("\nCompiling pattern: ");
2202 if (debug > 0)
2203 {
2204 unsigned debug_count;
2205
2206 for (debug_count = 0; debug_count < size; debug_count++)
2207 putchar (pattern[debug_count]);
2208 putchar ('\n');
2209 }
2210 #endif /* DEBUG */
2211
2212 /* Initialize the compile stack. */
2213 compile_stack.stack = TALLOC (INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
2214 if (compile_stack.stack == NULL)
2215 return REG_ESPACE;
2216
2217 compile_stack.size = INIT_COMPILE_STACK_SIZE;
2218 compile_stack.avail = 0;
2219
2220 range_table_work.table = 0;
2221 range_table_work.allocated = 0;
2222
2223 /* Initialize the pattern buffer. */
2224 bufp->syntax = syntax;
2225 bufp->fastmap_accurate = 0;
2226 bufp->not_bol = bufp->not_eol = 0;
2227
2228 /* Set `used' to zero, so that if we return an error, the pattern
2229 printer (for debugging) will think there's no pattern. We reset it
2230 at the end. */
2231 bufp->used = 0;
2232
2233 /* Always count groups, whether or not bufp->no_sub is set. */
2234 bufp->re_nsub = 0;
2235
2236 #if !defined emacs && !defined SYNTAX_TABLE
2237 /* Initialize the syntax table. */
2238 init_syntax_once ();
2239 #endif
2240
2241 if (bufp->allocated == 0)
2242 {
2243 if (bufp->buffer)
2244 { /* If zero allocated, but buffer is non-null, try to realloc
2245 enough space. This loses if buffer's address is bogus, but
2246 that is the user's responsibility. */
2247 RETALLOC (bufp->buffer, INIT_BUF_SIZE, unsigned char);
2248 }
2249 else
2250 { /* Caller did not allocate a buffer. Do it for them. */
2251 bufp->buffer = TALLOC (INIT_BUF_SIZE, unsigned char);
2252 }
2253 if (!bufp->buffer) FREE_STACK_RETURN (REG_ESPACE);
2254
2255 bufp->allocated = INIT_BUF_SIZE;
2256 }
2257
2258 begalt = b = bufp->buffer;
2259
2260 /* Loop through the uncompiled pattern until we're at the end. */
2261 while (p != pend)
2262 {
2263 PATFETCH (c);
2264
2265 switch (c)
2266 {
2267 case '^':
2268 {
2269 if ( /* If at start of pattern, it's an operator. */
2270 p == pattern + 1
2271 /* If context independent, it's an operator. */
2272 || syntax & RE_CONTEXT_INDEP_ANCHORS
2273 /* Otherwise, depends on what's come before. */
2274 || at_begline_loc_p (pattern, p, syntax))
2275 BUF_PUSH ((syntax & RE_NO_NEWLINE_ANCHOR) ? begbuf : begline);
2276 else
2277 goto normal_char;
2278 }
2279 break;
2280
2281
2282 case '$':
2283 {
2284 if ( /* If at end of pattern, it's an operator. */
2285 p == pend
2286 /* If context independent, it's an operator. */
2287 || syntax & RE_CONTEXT_INDEP_ANCHORS
2288 /* Otherwise, depends on what's next. */
2289 || at_endline_loc_p (p, pend, syntax))
2290 BUF_PUSH ((syntax & RE_NO_NEWLINE_ANCHOR) ? endbuf : endline);
2291 else
2292 goto normal_char;
2293 }
2294 break;
2295
2296
2297 case '+':
2298 case '?':
2299 if ((syntax & RE_BK_PLUS_QM)
2300 || (syntax & RE_LIMITED_OPS))
2301 goto normal_char;
2302 handle_plus:
2303 case '*':
2304 /* If there is no previous pattern... */
2305 if (!laststart)
2306 {
2307 if (syntax & RE_CONTEXT_INVALID_OPS)
2308 FREE_STACK_RETURN (REG_BADRPT);
2309 else if (!(syntax & RE_CONTEXT_INDEP_OPS))
2310 goto normal_char;
2311 }
2312
2313 {
2314 /* 1 means zero (many) matches is allowed. */
2315 boolean zero_times_ok = 0, many_times_ok = 0;
2316 boolean greedy = 1;
2317
2318 /* If there is a sequence of repetition chars, collapse it
2319 down to just one (the right one). We can't combine
2320 interval operators with these because of, e.g., `a{2}*',
2321 which should only match an even number of `a's. */
2322
2323 for (;;)
2324 {
2325 if ((syntax & RE_FRUGAL)
2326 && c == '?' && (zero_times_ok || many_times_ok))
2327 greedy = 0;
2328 else
2329 {
2330 zero_times_ok |= c != '+';
2331 many_times_ok |= c != '?';
2332 }
2333
2334 if (p == pend)
2335 break;
2336 else if (*p == '*'
2337 || (!(syntax & RE_BK_PLUS_QM)
2338 && (*p == '+' || *p == '?')))
2339 ;
2340 else if (syntax & RE_BK_PLUS_QM && *p == '\\')
2341 {
2342 if (p+1 == pend)
2343 FREE_STACK_RETURN (REG_EESCAPE);
2344 if (p[1] == '+' || p[1] == '?')
2345 PATFETCH (c); /* Gobble up the backslash. */
2346 else
2347 break;
2348 }
2349 else
2350 break;
2351 /* If we get here, we found another repeat character. */
2352 PATFETCH (c);
2353 }
2354
2355 /* Star, etc. applied to an empty pattern is equivalent
2356 to an empty pattern. */
2357 if (!laststart || laststart == b)
2358 break;
2359
2360 /* Now we know whether or not zero matches is allowed
2361 and also whether or not two or more matches is allowed. */
2362 if (greedy)
2363 {
2364 if (many_times_ok)
2365 {
2366 boolean simple = skip_one_char (laststart) == b;
2367 unsigned int startoffset = 0;
2368 re_opcode_t ofj =
2369 /* Check if the loop can match the empty string. */
2370 (simple || !analyse_first (laststart, b, NULL, 0)) ?
2371 on_failure_jump : on_failure_jump_loop;
2372 assert (skip_one_char (laststart) <= b);
2373
2374 if (!zero_times_ok && simple)
2375 { /* Since simple * loops can be made faster by using
2376 on_failure_keep_string_jump, we turn simple P+
2377 into PP* if P is simple. */
2378 unsigned char *p1, *p2;
2379 startoffset = b - laststart;
2380 GET_BUFFER_SPACE (startoffset);
2381 p1 = b; p2 = laststart;
2382 while (p2 < p1)
2383 *b++ = *p2++;
2384 zero_times_ok = 1;
2385 }
2386
2387 GET_BUFFER_SPACE (6);
2388 if (!zero_times_ok)
2389 /* A + loop. */
2390 STORE_JUMP (ofj, b, b + 6);
2391 else
2392 /* Simple * loops can use on_failure_keep_string_jump
2393 depending on what follows. But since we don't know
2394 that yet, we leave the decision up to
2395 on_failure_jump_smart. */
2396 INSERT_JUMP (simple ? on_failure_jump_smart : ofj,
2397 laststart + startoffset, b + 6);
2398 b += 3;
2399 STORE_JUMP (jump, b, laststart + startoffset);
2400 b += 3;
2401 }
2402 else
2403 {
2404 /* A simple ? pattern. */
2405 assert (zero_times_ok);
2406 GET_BUFFER_SPACE (3);
2407 INSERT_JUMP (on_failure_jump, laststart, b + 3);
2408 b += 3;
2409 }
2410 }
2411 else /* not greedy */
2412 { /* I wish the greedy and non-greedy cases could be merged. */
2413
2414 GET_BUFFER_SPACE (7); /* We might use less. */
2415 if (many_times_ok)
2416 {
2417 boolean emptyp = analyse_first (laststart, b, NULL, 0);
2418
2419 /* The non-greedy multiple match looks like a repeat..until:
2420 we only need a conditional jump at the end of the loop */
2421 if (emptyp) BUF_PUSH (no_op);
2422 STORE_JUMP (emptyp ? on_failure_jump_nastyloop
2423 : on_failure_jump, b, laststart);
2424 b += 3;
2425 if (zero_times_ok)
2426 {
2427 /* The repeat...until naturally matches one or more.
2428 To also match zero times, we need to first jump to
2429 the end of the loop (its conditional jump). */
2430 INSERT_JUMP (jump, laststart, b);
2431 b += 3;
2432 }
2433 }
2434 else
2435 {
2436 /* non-greedy a?? */
2437 INSERT_JUMP (jump, laststart, b + 3);
2438 b += 3;
2439 INSERT_JUMP (on_failure_jump, laststart, laststart + 6);
2440 b += 3;
2441 }
2442 }
2443 }
2444 pending_exact = 0;
2445 break;
2446
2447
2448 case '.':
2449 laststart = b;
2450 BUF_PUSH (anychar);
2451 break;
2452
2453
2454 case '[':
2455 {
2456 CLEAR_RANGE_TABLE_WORK_USED (range_table_work);
2457
2458 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2459
2460 /* Ensure that we have enough space to push a charset: the
2461 opcode, the length count, and the bitset; 34 bytes in all. */
2462 GET_BUFFER_SPACE (34);
2463
2464 laststart = b;
2465
2466 /* We test `*p == '^' twice, instead of using an if
2467 statement, so we only need one BUF_PUSH. */
2468 BUF_PUSH (*p == '^' ? charset_not : charset);
2469 if (*p == '^')
2470 p++;
2471
2472 /* Remember the first position in the bracket expression. */
2473 p1 = p;
2474
2475 /* Push the number of bytes in the bitmap. */
2476 BUF_PUSH ((1 << BYTEWIDTH) / BYTEWIDTH);
2477
2478 /* Clear the whole map. */
2479 bzero (b, (1 << BYTEWIDTH) / BYTEWIDTH);
2480
2481 /* charset_not matches newline according to a syntax bit. */
2482 if ((re_opcode_t) b[-2] == charset_not
2483 && (syntax & RE_HAT_LISTS_NOT_NEWLINE))
2484 SET_LIST_BIT ('\n');
2485
2486 /* Read in characters and ranges, setting map bits. */
2487 for (;;)
2488 {
2489 boolean escaped_char = false;
2490 const unsigned char *p2 = p;
2491
2492 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2493
2494 PATFETCH (c);
2495
2496 /* \ might escape characters inside [...] and [^...]. */
2497 if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\')
2498 {
2499 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2500
2501 PATFETCH (c);
2502 escaped_char = true;
2503 }
2504 else
2505 {
2506 /* Could be the end of the bracket expression. If it's
2507 not (i.e., when the bracket expression is `[]' so
2508 far), the ']' character bit gets set way below. */
2509 if (c == ']' && p2 != p1)
2510 break;
2511 }
2512
2513 /* What should we do for the character which is
2514 greater than 0x7F, but not BASE_LEADING_CODE_P?
2515 XXX */
2516
2517 /* See if we're at the beginning of a possible character
2518 class. */
2519
2520 if (!escaped_char &&
2521 syntax & RE_CHAR_CLASSES && c == '[' && *p == ':')
2522 {
2523 /* Leave room for the null. */
2524 unsigned char str[CHAR_CLASS_MAX_LENGTH + 1];
2525 const unsigned char *class_beg;
2526
2527 PATFETCH (c);
2528 c1 = 0;
2529 class_beg = p;
2530
2531 /* If pattern is `[[:'. */
2532 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2533
2534 for (;;)
2535 {
2536 PATFETCH (c);
2537 if ((c == ':' && *p == ']') || p == pend)
2538 break;
2539 if (c1 < CHAR_CLASS_MAX_LENGTH)
2540 str[c1++] = c;
2541 else
2542 /* This is in any case an invalid class name. */
2543 str[0] = '\0';
2544 }
2545 str[c1] = '\0';
2546
2547 /* If isn't a word bracketed by `[:' and `:]':
2548 undo the ending character, the letters, and
2549 leave the leading `:' and `[' (but set bits for
2550 them). */
2551 if (c == ':' && *p == ']')
2552 {
2553 int ch;
2554 re_wctype_t cc;
2555
2556 cc = re_wctype (str);
2557
2558 if (cc == 0)
2559 FREE_STACK_RETURN (REG_ECTYPE);
2560
2561 /* Throw away the ] at the end of the character
2562 class. */
2563 PATFETCH (c);
2564
2565 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2566
2567 /* Most character classes in a multibyte match
2568 just set a flag. Exceptions are is_blank,
2569 is_digit, is_cntrl, and is_xdigit, since
2570 they can only match ASCII characters. We
2571 don't need to handle them for multibyte.
2572 They are distinguished by a negative wctype. */
2573
2574 if (multibyte)
2575 SET_RANGE_TABLE_WORK_AREA_BIT (range_table_work,
2576 re_wctype_to_bit (cc));
2577
2578 for (ch = 0; ch < 1 << BYTEWIDTH; ++ch)
2579 {
2580 int translated = TRANSLATE (ch);
2581 if (re_iswctype (btowc (ch), cc))
2582 SET_LIST_BIT (translated);
2583 }
2584
2585 /* Repeat the loop. */
2586 continue;
2587 }
2588 else
2589 {
2590 /* Go back to right after the "[:". */
2591 p = class_beg;
2592 SET_LIST_BIT ('[');
2593
2594 /* Because the `:' may starts the range, we
2595 can't simply set bit and repeat the loop.
2596 Instead, just set it to C and handle below. */
2597 c = ':';
2598 }
2599 }
2600
2601 if (p < pend && p[0] == '-' && p[1] != ']')
2602 {
2603
2604 /* Discard the `-'. */
2605 PATFETCH (c1);
2606
2607 /* Fetch the character which ends the range. */
2608 PATFETCH (c1);
2609
2610 if (SINGLE_BYTE_CHAR_P (c))
2611 {
2612 if (! SINGLE_BYTE_CHAR_P (c1))
2613 {
2614 /* Handle a range starting with a
2615 character of less than 256, and ending
2616 with a character of not less than 256.
2617 Split that into two ranges, the low one
2618 ending at 0377, and the high one
2619 starting at the smallest character in
2620 the charset of C1 and ending at C1. */
2621 int charset = CHAR_CHARSET (c1);
2622 int c2 = MAKE_CHAR (charset, 0, 0);
2623
2624 SET_RANGE_TABLE_WORK_AREA (range_table_work,
2625 c2, c1);
2626 c1 = 0377;
2627 }
2628 }
2629 else if (!SAME_CHARSET_P (c, c1))
2630 FREE_STACK_RETURN (REG_ERANGE);
2631 }
2632 else
2633 /* Range from C to C. */
2634 c1 = c;
2635
2636 /* Set the range ... */
2637 if (SINGLE_BYTE_CHAR_P (c))
2638 /* ... into bitmap. */
2639 {
2640 re_wchar_t this_char;
2641 int range_start = c, range_end = c1;
2642
2643 /* If the start is after the end, the range is empty. */
2644 if (range_start > range_end)
2645 {
2646 if (syntax & RE_NO_EMPTY_RANGES)
2647 FREE_STACK_RETURN (REG_ERANGE);
2648 /* Else, repeat the loop. */
2649 }
2650 else
2651 {
2652 for (this_char = range_start; this_char <= range_end;
2653 this_char++)
2654 SET_LIST_BIT (TRANSLATE (this_char));
2655 }
2656 }
2657 else
2658 /* ... into range table. */
2659 SET_RANGE_TABLE_WORK_AREA (range_table_work, c, c1);
2660 }
2661
2662 /* Discard any (non)matching list bytes that are all 0 at the
2663 end of the map. Decrease the map-length byte too. */
2664 while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
2665 b[-1]--;
2666 b += b[-1];
2667
2668 /* Build real range table from work area. */
2669 if (RANGE_TABLE_WORK_USED (range_table_work)
2670 || RANGE_TABLE_WORK_BITS (range_table_work))
2671 {
2672 int i;
2673 int used = RANGE_TABLE_WORK_USED (range_table_work);
2674
2675 /* Allocate space for COUNT + RANGE_TABLE. Needs two
2676 bytes for flags, two for COUNT, and three bytes for
2677 each character. */
2678 GET_BUFFER_SPACE (4 + used * 3);
2679
2680 /* Indicate the existence of range table. */
2681 laststart[1] |= 0x80;
2682
2683 /* Store the character class flag bits into the range table.
2684 If not in emacs, these flag bits are always 0. */
2685 *b++ = RANGE_TABLE_WORK_BITS (range_table_work) & 0xff;
2686 *b++ = RANGE_TABLE_WORK_BITS (range_table_work) >> 8;
2687
2688 STORE_NUMBER_AND_INCR (b, used / 2);
2689 for (i = 0; i < used; i++)
2690 STORE_CHARACTER_AND_INCR
2691 (b, RANGE_TABLE_WORK_ELT (range_table_work, i));
2692 }
2693 }
2694 break;
2695
2696
2697 case '(':
2698 if (syntax & RE_NO_BK_PARENS)
2699 goto handle_open;
2700 else
2701 goto normal_char;
2702
2703
2704 case ')':
2705 if (syntax & RE_NO_BK_PARENS)
2706 goto handle_close;
2707 else
2708 goto normal_char;
2709
2710
2711 case '\n':
2712 if (syntax & RE_NEWLINE_ALT)
2713 goto handle_alt;
2714 else
2715 goto normal_char;
2716
2717
2718 case '|':
2719 if (syntax & RE_NO_BK_VBAR)
2720 goto handle_alt;
2721 else
2722 goto normal_char;
2723
2724
2725 case '{':
2726 if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
2727 goto handle_interval;
2728 else
2729 goto normal_char;
2730
2731
2732 case '\\':
2733 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2734
2735 /* Do not translate the character after the \, so that we can
2736 distinguish, e.g., \B from \b, even if we normally would
2737 translate, e.g., B to b. */
2738 PATFETCH_RAW (c);
2739
2740 switch (c)
2741 {
2742 case '(':
2743 if (syntax & RE_NO_BK_PARENS)
2744 goto normal_backslash;
2745
2746 handle_open:
2747 {
2748 int shy = 0;
2749 if (p+1 < pend)
2750 {
2751 /* Look for a special (?...) construct */
2752 if ((syntax & RE_SHY_GROUPS) && *p == '?')
2753 {
2754 PATFETCH (c); /* Gobble up the '?'. */
2755 PATFETCH (c);
2756 switch (c)
2757 {
2758 case ':': shy = 1; break;
2759 default:
2760 /* Only (?:...) is supported right now. */
2761 FREE_STACK_RETURN (REG_BADPAT);
2762 }
2763 }
2764 }
2765
2766 if (!shy)
2767 {
2768 bufp->re_nsub++;
2769 regnum++;
2770 }
2771
2772 if (COMPILE_STACK_FULL)
2773 {
2774 RETALLOC (compile_stack.stack, compile_stack.size << 1,
2775 compile_stack_elt_t);
2776 if (compile_stack.stack == NULL) return REG_ESPACE;
2777
2778 compile_stack.size <<= 1;
2779 }
2780
2781 /* These are the values to restore when we hit end of this
2782 group. They are all relative offsets, so that if the
2783 whole pattern moves because of realloc, they will still
2784 be valid. */
2785 COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
2786 COMPILE_STACK_TOP.fixup_alt_jump
2787 = fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
2788 COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
2789 COMPILE_STACK_TOP.regnum = shy ? -regnum : regnum;
2790
2791 /* Do not push a
2792 start_memory for groups beyond the last one we can
2793 represent in the compiled pattern. */
2794 if (regnum <= MAX_REGNUM && !shy)
2795 BUF_PUSH_2 (start_memory, regnum);
2796
2797 compile_stack.avail++;
2798
2799 fixup_alt_jump = 0;
2800 laststart = 0;
2801 begalt = b;
2802 /* If we've reached MAX_REGNUM groups, then this open
2803 won't actually generate any code, so we'll have to
2804 clear pending_exact explicitly. */
2805 pending_exact = 0;
2806 break;
2807 }
2808
2809 case ')':
2810 if (syntax & RE_NO_BK_PARENS) goto normal_backslash;
2811
2812 if (COMPILE_STACK_EMPTY)
2813 {
2814 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
2815 goto normal_backslash;
2816 else
2817 FREE_STACK_RETURN (REG_ERPAREN);
2818 }
2819
2820 handle_close:
2821 FIXUP_ALT_JUMP ();
2822
2823 /* See similar code for backslashed left paren above. */
2824 if (COMPILE_STACK_EMPTY)
2825 {
2826 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
2827 goto normal_char;
2828 else
2829 FREE_STACK_RETURN (REG_ERPAREN);
2830 }
2831
2832 /* Since we just checked for an empty stack above, this
2833 ``can't happen''. */
2834 assert (compile_stack.avail != 0);
2835 {
2836 /* We don't just want to restore into `regnum', because
2837 later groups should continue to be numbered higher,
2838 as in `(ab)c(de)' -- the second group is #2. */
2839 regnum_t this_group_regnum;
2840
2841 compile_stack.avail--;
2842 begalt = bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
2843 fixup_alt_jump
2844 = COMPILE_STACK_TOP.fixup_alt_jump
2845 ? bufp->buffer + COMPILE_STACK_TOP.fixup_alt_jump - 1
2846 : 0;
2847 laststart = bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
2848 this_group_regnum = COMPILE_STACK_TOP.regnum;
2849 /* If we've reached MAX_REGNUM groups, then this open
2850 won't actually generate any code, so we'll have to
2851 clear pending_exact explicitly. */
2852 pending_exact = 0;
2853
2854 /* We're at the end of the group, so now we know how many
2855 groups were inside this one. */
2856 if (this_group_regnum <= MAX_REGNUM && this_group_regnum > 0)
2857 BUF_PUSH_2 (stop_memory, this_group_regnum);
2858 }
2859 break;
2860
2861
2862 case '|': /* `\|'. */
2863 if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
2864 goto normal_backslash;
2865 handle_alt:
2866 if (syntax & RE_LIMITED_OPS)
2867 goto normal_char;
2868
2869 /* Insert before the previous alternative a jump which
2870 jumps to this alternative if the former fails. */
2871 GET_BUFFER_SPACE (3);
2872 INSERT_JUMP (on_failure_jump, begalt, b + 6);
2873 pending_exact = 0;
2874 b += 3;
2875
2876 /* The alternative before this one has a jump after it
2877 which gets executed if it gets matched. Adjust that
2878 jump so it will jump to this alternative's analogous
2879 jump (put in below, which in turn will jump to the next
2880 (if any) alternative's such jump, etc.). The last such
2881 jump jumps to the correct final destination. A picture:
2882 _____ _____
2883 | | | |
2884 | v | v
2885 a | b | c
2886
2887 If we are at `b', then fixup_alt_jump right now points to a
2888 three-byte space after `a'. We'll put in the jump, set
2889 fixup_alt_jump to right after `b', and leave behind three
2890 bytes which we'll fill in when we get to after `c'. */
2891
2892 FIXUP_ALT_JUMP ();
2893
2894 /* Mark and leave space for a jump after this alternative,
2895 to be filled in later either by next alternative or
2896 when know we're at the end of a series of alternatives. */
2897 fixup_alt_jump = b;
2898 GET_BUFFER_SPACE (3);
2899 b += 3;
2900
2901 laststart = 0;
2902 begalt = b;
2903 break;
2904
2905
2906 case '{':
2907 /* If \{ is a literal. */
2908 if (!(syntax & RE_INTERVALS)
2909 /* If we're at `\{' and it's not the open-interval
2910 operator. */
2911 || (syntax & RE_NO_BK_BRACES))
2912 goto normal_backslash;
2913
2914 handle_interval:
2915 {
2916 /* If got here, then the syntax allows intervals. */
2917
2918 /* At least (most) this many matches must be made. */
2919 int lower_bound = 0, upper_bound = -1;
2920
2921 beg_interval = p;
2922
2923 if (p == pend)
2924 FREE_STACK_RETURN (REG_EBRACE);
2925
2926 GET_UNSIGNED_NUMBER (lower_bound);
2927
2928 if (c == ',')
2929 GET_UNSIGNED_NUMBER (upper_bound);
2930 else
2931 /* Interval such as `{1}' => match exactly once. */
2932 upper_bound = lower_bound;
2933
2934 if (lower_bound < 0 || upper_bound > RE_DUP_MAX
2935 || (upper_bound >= 0 && lower_bound > upper_bound))
2936 FREE_STACK_RETURN (REG_BADBR);
2937
2938 if (!(syntax & RE_NO_BK_BRACES))
2939 {
2940 if (c != '\\')
2941 FREE_STACK_RETURN (REG_BADBR);
2942
2943 PATFETCH (c);
2944 }
2945
2946 if (c != '}')
2947 FREE_STACK_RETURN (REG_BADBR);
2948
2949 /* We just parsed a valid interval. */
2950
2951 /* If it's invalid to have no preceding re. */
2952 if (!laststart)
2953 {
2954 if (syntax & RE_CONTEXT_INVALID_OPS)
2955 FREE_STACK_RETURN (REG_BADRPT);
2956 else if (syntax & RE_CONTEXT_INDEP_OPS)
2957 laststart = b;
2958 else
2959 goto unfetch_interval;
2960 }
2961
2962 if (upper_bound == 0)
2963 /* If the upper bound is zero, just drop the sub pattern
2964 altogether. */
2965 b = laststart;
2966 else if (lower_bound == 1 && upper_bound == 1)
2967 /* Just match it once: nothing to do here. */
2968 ;
2969
2970 /* Otherwise, we have a nontrivial interval. When
2971 we're all done, the pattern will look like:
2972 set_number_at <jump count> <upper bound>
2973 set_number_at <succeed_n count> <lower bound>
2974 succeed_n <after jump addr> <succeed_n count>
2975 <body of loop>
2976 jump_n <succeed_n addr> <jump count>
2977 (The upper bound and `jump_n' are omitted if
2978 `upper_bound' is 1, though.) */
2979 else
2980 { /* If the upper bound is > 1, we need to insert
2981 more at the end of the loop. */
2982 unsigned int nbytes = (upper_bound < 0 ? 3
2983 : upper_bound > 1 ? 5 : 0);
2984 unsigned int startoffset = 0;
2985
2986 GET_BUFFER_SPACE (20); /* We might use less. */
2987
2988 if (lower_bound == 0)
2989 {
2990 /* A succeed_n that starts with 0 is really a
2991 a simple on_failure_jump_loop. */
2992 INSERT_JUMP (on_failure_jump_loop, laststart,
2993 b + 3 + nbytes);
2994 b += 3;
2995 }
2996 else
2997 {
2998 /* Initialize lower bound of the `succeed_n', even
2999 though it will be set during matching by its
3000 attendant `set_number_at' (inserted next),
3001 because `re_compile_fastmap' needs to know.
3002 Jump to the `jump_n' we might insert below. */
3003 INSERT_JUMP2 (succeed_n, laststart,
3004 b + 5 + nbytes,
3005 lower_bound);
3006 b += 5;
3007
3008 /* Code to initialize the lower bound. Insert
3009 before the `succeed_n'. The `5' is the last two
3010 bytes of this `set_number_at', plus 3 bytes of
3011 the following `succeed_n'. */
3012 insert_op2 (set_number_at, laststart, 5, lower_bound, b);
3013 b += 5;
3014 startoffset += 5;
3015 }
3016
3017 if (upper_bound < 0)
3018 {
3019 /* A negative upper bound stands for infinity,
3020 in which case it degenerates to a plain jump. */
3021 STORE_JUMP (jump, b, laststart + startoffset);
3022 b += 3;
3023 }
3024 else if (upper_bound > 1)
3025 { /* More than one repetition is allowed, so
3026 append a backward jump to the `succeed_n'
3027 that starts this interval.
3028
3029 When we've reached this during matching,
3030 we'll have matched the interval once, so
3031 jump back only `upper_bound - 1' times. */
3032 STORE_JUMP2 (jump_n, b, laststart + startoffset,
3033 upper_bound - 1);
3034 b += 5;
3035
3036 /* The location we want to set is the second
3037 parameter of the `jump_n'; that is `b-2' as
3038 an absolute address. `laststart' will be
3039 the `set_number_at' we're about to insert;
3040 `laststart+3' the number to set, the source
3041 for the relative address. But we are
3042 inserting into the middle of the pattern --
3043 so everything is getting moved up by 5.
3044 Conclusion: (b - 2) - (laststart + 3) + 5,
3045 i.e., b - laststart.
3046
3047 We insert this at the beginning of the loop
3048 so that if we fail during matching, we'll
3049 reinitialize the bounds. */
3050 insert_op2 (set_number_at, laststart, b - laststart,
3051 upper_bound - 1, b);
3052 b += 5;
3053 }
3054 }
3055 pending_exact = 0;
3056 beg_interval = NULL;
3057 }
3058 break;
3059
3060 unfetch_interval:
3061 /* If an invalid interval, match the characters as literals. */
3062 assert (beg_interval);
3063 p = beg_interval;
3064 beg_interval = NULL;
3065
3066 /* normal_char and normal_backslash need `c'. */
3067 c = '{';
3068
3069 if (!(syntax & RE_NO_BK_BRACES))
3070 {
3071 assert (p > pattern && p[-1] == '\\');
3072 goto normal_backslash;
3073 }
3074 else
3075 goto normal_char;
3076
3077 #ifdef emacs
3078 /* There is no way to specify the before_dot and after_dot
3079 operators. rms says this is ok. --karl */
3080 case '=':
3081 BUF_PUSH (at_dot);
3082 break;
3083
3084 case 's':
3085 laststart = b;
3086 PATFETCH (c);
3087 BUF_PUSH_2 (syntaxspec, syntax_spec_code[c]);
3088 break;
3089
3090 case 'S':
3091 laststart = b;
3092 PATFETCH (c);
3093 BUF_PUSH_2 (notsyntaxspec, syntax_spec_code[c]);
3094 break;
3095
3096 case 'c':
3097 laststart = b;
3098 PATFETCH_RAW (c);
3099 BUF_PUSH_2 (categoryspec, c);
3100 break;
3101
3102 case 'C':
3103 laststart = b;
3104 PATFETCH_RAW (c);
3105 BUF_PUSH_2 (notcategoryspec, c);
3106 break;
3107 #endif /* emacs */
3108
3109
3110 case 'w':
3111 if (syntax & RE_NO_GNU_OPS)
3112 goto normal_char;
3113 laststart = b;
3114 BUF_PUSH_2 (syntaxspec, Sword);
3115 break;
3116
3117
3118 case 'W':
3119 if (syntax & RE_NO_GNU_OPS)
3120 goto normal_char;
3121 laststart = b;
3122 BUF_PUSH_2 (notsyntaxspec, Sword);
3123 break;
3124
3125
3126 case '<':
3127 if (syntax & RE_NO_GNU_OPS)
3128 goto normal_char;
3129 BUF_PUSH (wordbeg);
3130 break;
3131
3132 case '>':
3133 if (syntax & RE_NO_GNU_OPS)
3134 goto normal_char;
3135 BUF_PUSH (wordend);
3136 break;
3137
3138 case 'b':
3139 if (syntax & RE_NO_GNU_OPS)
3140 goto normal_char;
3141 BUF_PUSH (wordbound);
3142 break;
3143
3144 case 'B':
3145 if (syntax & RE_NO_GNU_OPS)
3146 goto normal_char;
3147 BUF_PUSH (notwordbound);
3148 break;
3149
3150 case '`':
3151 if (syntax & RE_NO_GNU_OPS)
3152 goto normal_char;
3153 BUF_PUSH (begbuf);
3154 break;
3155
3156 case '\'':
3157 if (syntax & RE_NO_GNU_OPS)
3158 goto normal_char;
3159 BUF_PUSH (endbuf);
3160 break;
3161
3162 case '1': case '2': case '3': case '4': case '5':
3163 case '6': case '7': case '8': case '9':
3164 {
3165 regnum_t reg;
3166
3167 if (syntax & RE_NO_BK_REFS)
3168 goto normal_backslash;
3169
3170 reg = c - '0';
3171
3172 /* Can't back reference to a subexpression before its end. */
3173 if (reg > regnum || group_in_compile_stack (compile_stack, reg))
3174 FREE_STACK_RETURN (REG_ESUBREG);
3175
3176 laststart = b;
3177 BUF_PUSH_2 (duplicate, reg);
3178 }
3179 break;
3180
3181
3182 case '+':
3183 case '?':
3184 if (syntax & RE_BK_PLUS_QM)
3185 goto handle_plus;
3186 else
3187 goto normal_backslash;
3188
3189 default:
3190 normal_backslash:
3191 /* You might think it would be useful for \ to mean
3192 not to translate; but if we don't translate it
3193 it will never match anything. */
3194 c = TRANSLATE (c);
3195 goto normal_char;
3196 }
3197 break;
3198
3199
3200 default:
3201 /* Expects the character in `c'. */
3202 normal_char:
3203 /* If no exactn currently being built. */
3204 if (!pending_exact
3205
3206 /* If last exactn not at current position. */
3207 || pending_exact + *pending_exact + 1 != b
3208
3209 /* We have only one byte following the exactn for the count. */
3210 || *pending_exact >= (1 << BYTEWIDTH) - MAX_MULTIBYTE_LENGTH
3211
3212 /* If followed by a repetition operator. */
3213 || (p != pend && (*p == '*' || *p == '^'))
3214 || ((syntax & RE_BK_PLUS_QM)
3215 ? p + 1 < pend && *p == '\\' && (p[1] == '+' || p[1] == '?')
3216 : p != pend && (*p == '+' || *p == '?'))
3217 || ((syntax & RE_INTERVALS)
3218 && ((syntax & RE_NO_BK_BRACES)
3219 ? p != pend && *p == '{'
3220 : p + 1 < pend && p[0] == '\\' && p[1] == '{')))
3221 {
3222 /* Start building a new exactn. */
3223
3224 laststart = b;
3225
3226 BUF_PUSH_2 (exactn, 0);
3227 pending_exact = b - 1;
3228 }
3229
3230 GET_BUFFER_SPACE (MAX_MULTIBYTE_LENGTH);
3231 {
3232 int len;
3233
3234 if (multibyte)
3235 len = CHAR_STRING (c, b);
3236 else
3237 *b = c, len = 1;
3238 b += len;
3239 (*pending_exact) += len;
3240 }
3241
3242 break;
3243 } /* switch (c) */
3244 } /* while p != pend */
3245
3246
3247 /* Through the pattern now. */
3248
3249 FIXUP_ALT_JUMP ();
3250
3251 if (!COMPILE_STACK_EMPTY)
3252 FREE_STACK_RETURN (REG_EPAREN);
3253
3254 /* If we don't want backtracking, force success
3255 the first time we reach the end of the compiled pattern. */
3256 if (syntax & RE_NO_POSIX_BACKTRACKING)
3257 BUF_PUSH (succeed);
3258
3259 free (compile_stack.stack);
3260
3261 /* We have succeeded; set the length of the buffer. */
3262 bufp->used = b - bufp->buffer;
3263
3264 #ifdef DEBUG
3265 if (debug > 0)
3266 {
3267 re_compile_fastmap (bufp);
3268 DEBUG_PRINT1 ("\nCompiled pattern: \n");
3269 print_compiled_pattern (bufp);
3270 }
3271 debug--;
3272 #endif /* DEBUG */
3273
3274 #ifndef MATCH_MAY_ALLOCATE
3275 /* Initialize the failure stack to the largest possible stack. This
3276 isn't necessary unless we're trying to avoid calling alloca in
3277 the search and match routines. */
3278 {
3279 int num_regs = bufp->re_nsub + 1;
3280
3281 if (fail_stack.size < re_max_failures * TYPICAL_FAILURE_SIZE)
3282 {
3283 fail_stack.size = re_max_failures * TYPICAL_FAILURE_SIZE;
3284
3285 if (! fail_stack.stack)
3286 fail_stack.stack
3287 = (fail_stack_elt_t *) malloc (fail_stack.size
3288 * sizeof (fail_stack_elt_t));
3289 else
3290 fail_stack.stack
3291 = (fail_stack_elt_t *) realloc (fail_stack.stack,
3292 (fail_stack.size
3293 * sizeof (fail_stack_elt_t)));
3294 }
3295
3296 regex_grow_registers (num_regs);
3297 }
3298 #endif /* not MATCH_MAY_ALLOCATE */
3299
3300 return REG_NOERROR;
3301 } /* regex_compile */
3302 \f
3303 /* Subroutines for `regex_compile'. */
3304
3305 /* Store OP at LOC followed by two-byte integer parameter ARG. */
3306
3307 static void
3308 store_op1 (op, loc, arg)
3309 re_opcode_t op;
3310 unsigned char *loc;
3311 int arg;
3312 {
3313 *loc = (unsigned char) op;
3314 STORE_NUMBER (loc + 1, arg);
3315 }
3316
3317
3318 /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
3319
3320 static void
3321 store_op2 (op, loc, arg1, arg2)
3322 re_opcode_t op;
3323 unsigned char *loc;
3324 int arg1, arg2;
3325 {
3326 *loc = (unsigned char) op;
3327 STORE_NUMBER (loc + 1, arg1);
3328 STORE_NUMBER (loc + 3, arg2);
3329 }
3330
3331
3332 /* Copy the bytes from LOC to END to open up three bytes of space at LOC
3333 for OP followed by two-byte integer parameter ARG. */
3334
3335 static void
3336 insert_op1 (op, loc, arg, end)
3337 re_opcode_t op;
3338 unsigned char *loc;
3339 int arg;
3340 unsigned char *end;
3341 {
3342 register unsigned char *pfrom = end;
3343 register unsigned char *pto = end + 3;
3344
3345 while (pfrom != loc)
3346 *--pto = *--pfrom;
3347
3348 store_op1 (op, loc, arg);
3349 }
3350
3351
3352 /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
3353
3354 static void
3355 insert_op2 (op, loc, arg1, arg2, end)
3356 re_opcode_t op;
3357 unsigned char *loc;
3358 int arg1, arg2;
3359 unsigned char *end;
3360 {
3361 register unsigned char *pfrom = end;
3362 register unsigned char *pto = end + 5;
3363
3364 while (pfrom != loc)
3365 *--pto = *--pfrom;
3366
3367 store_op2 (op, loc, arg1, arg2);
3368 }
3369
3370
3371 /* P points to just after a ^ in PATTERN. Return true if that ^ comes
3372 after an alternative or a begin-subexpression. We assume there is at
3373 least one character before the ^. */
3374
3375 static boolean
3376 at_begline_loc_p (pattern, p, syntax)
3377 re_char *pattern, *p;
3378 reg_syntax_t syntax;
3379 {
3380 re_char *prev = p - 2;
3381 boolean prev_prev_backslash = prev > pattern && prev[-1] == '\\';
3382
3383 return
3384 /* After a subexpression? */
3385 (*prev == '(' && (syntax & RE_NO_BK_PARENS || prev_prev_backslash))
3386 /* After an alternative? */
3387 || (*prev == '|' && (syntax & RE_NO_BK_VBAR || prev_prev_backslash))
3388 /* After a shy subexpression? */
3389 || ((syntax & RE_SHY_GROUPS) && prev - 2 >= pattern
3390 && prev[-1] == '?' && prev[-2] == '('
3391 && (syntax & RE_NO_BK_PARENS
3392 || (prev - 3 >= pattern && prev[-3] == '\\')));
3393 }
3394
3395
3396 /* The dual of at_begline_loc_p. This one is for $. We assume there is
3397 at least one character after the $, i.e., `P < PEND'. */
3398
3399 static boolean
3400 at_endline_loc_p (p, pend, syntax)
3401 re_char *p, *pend;
3402 reg_syntax_t syntax;
3403 {
3404 re_char *next = p;
3405 boolean next_backslash = *next == '\\';
3406 re_char *next_next = p + 1 < pend ? p + 1 : 0;
3407
3408 return
3409 /* Before a subexpression? */
3410 (syntax & RE_NO_BK_PARENS ? *next == ')'
3411 : next_backslash && next_next && *next_next == ')')
3412 /* Before an alternative? */
3413 || (syntax & RE_NO_BK_VBAR ? *next == '|'
3414 : next_backslash && next_next && *next_next == '|');
3415 }
3416
3417
3418 /* Returns true if REGNUM is in one of COMPILE_STACK's elements and
3419 false if it's not. */
3420
3421 static boolean
3422 group_in_compile_stack (compile_stack, regnum)
3423 compile_stack_type compile_stack;
3424 regnum_t regnum;
3425 {
3426 int this_element;
3427
3428 for (this_element = compile_stack.avail - 1;
3429 this_element >= 0;
3430 this_element--)
3431 if (compile_stack.stack[this_element].regnum == regnum)
3432 return true;
3433
3434 return false;
3435 }
3436 \f
3437 /* analyse_first.
3438 If fastmap is non-NULL, go through the pattern and fill fastmap
3439 with all the possible leading chars. If fastmap is NULL, don't
3440 bother filling it up (obviously) and only return whether the
3441 pattern could potentially match the empty string.
3442
3443 Return 1 if p..pend might match the empty string.
3444 Return 0 if p..pend matches at least one char.
3445 Return -1 if fastmap was not updated accurately. */
3446
3447 static int
3448 analyse_first (p, pend, fastmap, multibyte)
3449 re_char *p, *pend;
3450 char *fastmap;
3451 const int multibyte;
3452 {
3453 int j, k;
3454 boolean not;
3455
3456 /* If all elements for base leading-codes in fastmap is set, this
3457 flag is set true. */
3458 boolean match_any_multibyte_characters = false;
3459
3460 assert (p);
3461
3462 /* The loop below works as follows:
3463 - It has a working-list kept in the PATTERN_STACK and which basically
3464 starts by only containing a pointer to the first operation.
3465 - If the opcode we're looking at is a match against some set of
3466 chars, then we add those chars to the fastmap and go on to the
3467 next work element from the worklist (done via `break').
3468 - If the opcode is a control operator on the other hand, we either
3469 ignore it (if it's meaningless at this point, such as `start_memory')
3470 or execute it (if it's a jump). If the jump has several destinations
3471 (i.e. `on_failure_jump'), then we push the other destination onto the
3472 worklist.
3473 We guarantee termination by ignoring backward jumps (more or less),
3474 so that `p' is monotonically increasing. More to the point, we
3475 never set `p' (or push) anything `<= p1'. */
3476
3477 while (p < pend)
3478 {
3479 /* `p1' is used as a marker of how far back a `on_failure_jump'
3480 can go without being ignored. It is normally equal to `p'
3481 (which prevents any backward `on_failure_jump') except right
3482 after a plain `jump', to allow patterns such as:
3483 0: jump 10
3484 3..9: <body>
3485 10: on_failure_jump 3
3486 as used for the *? operator. */
3487 re_char *p1 = p;
3488
3489 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
3490 {
3491 case succeed:
3492 return 1;
3493 continue;
3494
3495 case duplicate:
3496 /* If the first character has to match a backreference, that means
3497 that the group was empty (since it already matched). Since this
3498 is the only case that interests us here, we can assume that the
3499 backreference must match the empty string. */
3500 p++;
3501 continue;
3502
3503
3504 /* Following are the cases which match a character. These end
3505 with `break'. */
3506
3507 case exactn:
3508 if (fastmap)
3509 {
3510 int c = RE_STRING_CHAR (p + 1, pend - p);
3511
3512 if (SINGLE_BYTE_CHAR_P (c))
3513 fastmap[c] = 1;
3514 else
3515 fastmap[p[1]] = 1;
3516 }
3517 break;
3518
3519
3520 case anychar:
3521 /* We could put all the chars except for \n (and maybe \0)
3522 but we don't bother since it is generally not worth it. */
3523 if (!fastmap) break;
3524 return -1;
3525
3526
3527 case charset_not:
3528 /* Chars beyond end of bitmap are possible matches.
3529 All the single-byte codes can occur in multibyte buffers.
3530 So any that are not listed in the charset
3531 are possible matches, even in multibyte buffers. */
3532 if (!fastmap) break;
3533 for (j = CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH;
3534 j < (1 << BYTEWIDTH); j++)
3535 fastmap[j] = 1;
3536 /* Fallthrough */
3537 case charset:
3538 if (!fastmap) break;
3539 not = (re_opcode_t) *(p - 1) == charset_not;
3540 for (j = CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH - 1, p++;
3541 j >= 0; j--)
3542 if (!!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))) ^ not)
3543 fastmap[j] = 1;
3544
3545 if ((not && multibyte)
3546 /* Any character set can possibly contain a character
3547 which doesn't match the specified set of characters. */
3548 || (CHARSET_RANGE_TABLE_EXISTS_P (&p[-2])
3549 && CHARSET_RANGE_TABLE_BITS (&p[-2]) != 0))
3550 /* If we can match a character class, we can match
3551 any character set. */
3552 {
3553 set_fastmap_for_multibyte_characters:
3554 if (match_any_multibyte_characters == false)
3555 {
3556 for (j = 0x80; j < 0xA0; j++) /* XXX */
3557 if (BASE_LEADING_CODE_P (j))
3558 fastmap[j] = 1;
3559 match_any_multibyte_characters = true;
3560 }
3561 }
3562
3563 else if (!not && CHARSET_RANGE_TABLE_EXISTS_P (&p[-2])
3564 && match_any_multibyte_characters == false)
3565 {
3566 /* Set fastmap[I] 1 where I is a base leading code of each
3567 multibyte character in the range table. */
3568 int c, count;
3569
3570 /* Make P points the range table. `+ 2' is to skip flag
3571 bits for a character class. */
3572 p += CHARSET_BITMAP_SIZE (&p[-2]) + 2;
3573
3574 /* Extract the number of ranges in range table into COUNT. */
3575 EXTRACT_NUMBER_AND_INCR (count, p);
3576 for (; count > 0; count--, p += 2 * 3) /* XXX */
3577 {
3578 /* Extract the start of each range. */
3579 EXTRACT_CHARACTER (c, p);
3580 j = CHAR_CHARSET (c);
3581 fastmap[CHARSET_LEADING_CODE_BASE (j)] = 1;
3582 }
3583 }
3584 break;
3585
3586 case syntaxspec:
3587 case notsyntaxspec:
3588 if (!fastmap) break;
3589 #ifndef emacs
3590 not = (re_opcode_t)p[-1] == notsyntaxspec;
3591 k = *p++;
3592 for (j = 0; j < (1 << BYTEWIDTH); j++)
3593 if ((SYNTAX (j) == (enum syntaxcode) k) ^ not)
3594 fastmap[j] = 1;
3595 break;
3596 #else /* emacs */
3597 /* This match depends on text properties. These end with
3598 aborting optimizations. */
3599 return -1;
3600
3601 case categoryspec:
3602 case notcategoryspec:
3603 if (!fastmap) break;
3604 not = (re_opcode_t)p[-1] == notcategoryspec;
3605 k = *p++;
3606 for (j = 0; j < (1 << BYTEWIDTH); j++)
3607 if ((CHAR_HAS_CATEGORY (j, k)) ^ not)
3608 fastmap[j] = 1;
3609
3610 if (multibyte)
3611 /* Any character set can possibly contain a character
3612 whose category is K (or not). */
3613 goto set_fastmap_for_multibyte_characters;
3614 break;
3615
3616 /* All cases after this match the empty string. These end with
3617 `continue'. */
3618
3619 case before_dot:
3620 case at_dot:
3621 case after_dot:
3622 #endif /* !emacs */
3623 case no_op:
3624 case begline:
3625 case endline:
3626 case begbuf:
3627 case endbuf:
3628 case wordbound:
3629 case notwordbound:
3630 case wordbeg:
3631 case wordend:
3632 continue;
3633
3634
3635 case jump:
3636 EXTRACT_NUMBER_AND_INCR (j, p);
3637 if (j < 0)
3638 /* Backward jumps can only go back to code that we've already
3639 visited. `re_compile' should make sure this is true. */
3640 break;
3641 p += j;
3642 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p))
3643 {
3644 case on_failure_jump:
3645 case on_failure_keep_string_jump:
3646 case on_failure_jump_loop:
3647 case on_failure_jump_nastyloop:
3648 case on_failure_jump_smart:
3649 p++;
3650 break;
3651 default:
3652 continue;
3653 };
3654 /* Keep `p1' to allow the `on_failure_jump' we are jumping to
3655 to jump back to "just after here". */
3656 /* Fallthrough */
3657
3658 case on_failure_jump:
3659 case on_failure_keep_string_jump:
3660 case on_failure_jump_nastyloop:
3661 case on_failure_jump_loop:
3662 case on_failure_jump_smart:
3663 EXTRACT_NUMBER_AND_INCR (j, p);
3664 if (p + j <= p1)
3665 ; /* Backward jump to be ignored. */
3666 else
3667 { /* We have to look down both arms.
3668 We first go down the "straight" path so as to minimize
3669 stack usage when going through alternatives. */
3670 int r = analyse_first (p, pend, fastmap, multibyte);
3671 if (r) return r;
3672 p += j;
3673 }
3674 continue;
3675
3676
3677 case jump_n:
3678 /* This code simply does not properly handle forward jump_n. */
3679 DEBUG_STATEMENT (EXTRACT_NUMBER (j, p); assert (j < 0));
3680 p += 4;
3681 /* jump_n can either jump or fall through. The (backward) jump
3682 case has already been handled, so we only need to look at the
3683 fallthrough case. */
3684 continue;
3685
3686 case succeed_n:
3687 /* If N == 0, it should be an on_failure_jump_loop instead. */
3688 DEBUG_STATEMENT (EXTRACT_NUMBER (j, p + 2); assert (j > 0));
3689 p += 4;
3690 /* We only care about one iteration of the loop, so we don't
3691 need to consider the case where this behaves like an
3692 on_failure_jump. */
3693 continue;
3694
3695
3696 case set_number_at:
3697 p += 4;
3698 continue;
3699
3700
3701 case start_memory:
3702 case stop_memory:
3703 p += 1;
3704 continue;
3705
3706
3707 default:
3708 abort (); /* We have listed all the cases. */
3709 } /* switch *p++ */
3710
3711 /* Getting here means we have found the possible starting
3712 characters for one path of the pattern -- and that the empty
3713 string does not match. We need not follow this path further. */
3714 return 0;
3715 } /* while p */
3716
3717 /* We reached the end without matching anything. */
3718 return 1;
3719
3720 } /* analyse_first */
3721 \f
3722 /* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
3723 BUFP. A fastmap records which of the (1 << BYTEWIDTH) possible
3724 characters can start a string that matches the pattern. This fastmap
3725 is used by re_search to skip quickly over impossible starting points.
3726
3727 Character codes above (1 << BYTEWIDTH) are not represented in the
3728 fastmap, but the leading codes are represented. Thus, the fastmap
3729 indicates which character sets could start a match.
3730
3731 The caller must supply the address of a (1 << BYTEWIDTH)-byte data
3732 area as BUFP->fastmap.
3733
3734 We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
3735 the pattern buffer.
3736
3737 Returns 0 if we succeed, -2 if an internal error. */
3738
3739 int
3740 re_compile_fastmap (bufp)
3741 struct re_pattern_buffer *bufp;
3742 {
3743 char *fastmap = bufp->fastmap;
3744 int analysis;
3745
3746 assert (fastmap && bufp->buffer);
3747
3748 bzero (fastmap, 1 << BYTEWIDTH); /* Assume nothing's valid. */
3749 bufp->fastmap_accurate = 1; /* It will be when we're done. */
3750
3751 analysis = analyse_first (bufp->buffer, bufp->buffer + bufp->used,
3752 fastmap, RE_MULTIBYTE_P (bufp));
3753 bufp->can_be_null = (analysis != 0);
3754 return 0;
3755 } /* re_compile_fastmap */
3756 \f
3757 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
3758 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
3759 this memory for recording register information. STARTS and ENDS
3760 must be allocated using the malloc library routine, and must each
3761 be at least NUM_REGS * sizeof (regoff_t) bytes long.
3762
3763 If NUM_REGS == 0, then subsequent matches should allocate their own
3764 register data.
3765
3766 Unless this function is called, the first search or match using
3767 PATTERN_BUFFER will allocate its own register data, without
3768 freeing the old data. */
3769
3770 void
3771 re_set_registers (bufp, regs, num_regs, starts, ends)
3772 struct re_pattern_buffer *bufp;
3773 struct re_registers *regs;
3774 unsigned num_regs;
3775 regoff_t *starts, *ends;
3776 {
3777 if (num_regs)
3778 {
3779 bufp->regs_allocated = REGS_REALLOCATE;
3780 regs->num_regs = num_regs;
3781 regs->start = starts;
3782 regs->end = ends;
3783 }
3784 else
3785 {
3786 bufp->regs_allocated = REGS_UNALLOCATED;
3787 regs->num_regs = 0;
3788 regs->start = regs->end = (regoff_t *) 0;
3789 }
3790 }
3791 WEAK_ALIAS (__re_set_registers, re_set_registers)
3792 \f
3793 /* Searching routines. */
3794
3795 /* Like re_search_2, below, but only one string is specified, and
3796 doesn't let you say where to stop matching. */
3797
3798 int
3799 re_search (bufp, string, size, startpos, range, regs)
3800 struct re_pattern_buffer *bufp;
3801 const char *string;
3802 int size, startpos, range;
3803 struct re_registers *regs;
3804 {
3805 return re_search_2 (bufp, NULL, 0, string, size, startpos, range,
3806 regs, size);
3807 }
3808 WEAK_ALIAS (__re_search, re_search)
3809
3810 /* End address of virtual concatenation of string. */
3811 #define STOP_ADDR_VSTRING(P) \
3812 (((P) >= size1 ? string2 + size2 : string1 + size1))
3813
3814 /* Address of POS in the concatenation of virtual string. */
3815 #define POS_ADDR_VSTRING(POS) \
3816 (((POS) >= size1 ? string2 - size1 : string1) + (POS))
3817
3818 /* Using the compiled pattern in BUFP->buffer, first tries to match the
3819 virtual concatenation of STRING1 and STRING2, starting first at index
3820 STARTPOS, then at STARTPOS + 1, and so on.
3821
3822 STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
3823
3824 RANGE is how far to scan while trying to match. RANGE = 0 means try
3825 only at STARTPOS; in general, the last start tried is STARTPOS +
3826 RANGE.
3827
3828 In REGS, return the indices of the virtual concatenation of STRING1
3829 and STRING2 that matched the entire BUFP->buffer and its contained
3830 subexpressions.
3831
3832 Do not consider matching one past the index STOP in the virtual
3833 concatenation of STRING1 and STRING2.
3834
3835 We return either the position in the strings at which the match was
3836 found, -1 if no match, or -2 if error (such as failure
3837 stack overflow). */
3838
3839 int
3840 re_search_2 (bufp, str1, size1, str2, size2, startpos, range, regs, stop)
3841 struct re_pattern_buffer *bufp;
3842 const char *str1, *str2;
3843 int size1, size2;
3844 int startpos;
3845 int range;
3846 struct re_registers *regs;
3847 int stop;
3848 {
3849 int val;
3850 re_char *string1 = (re_char*) str1;
3851 re_char *string2 = (re_char*) str2;
3852 register char *fastmap = bufp->fastmap;
3853 register RE_TRANSLATE_TYPE translate = bufp->translate;
3854 int total_size = size1 + size2;
3855 int endpos = startpos + range;
3856 boolean anchored_start;
3857
3858 /* Nonzero if we have to concern multibyte character. */
3859 const boolean multibyte = RE_MULTIBYTE_P (bufp);
3860
3861 /* Check for out-of-range STARTPOS. */
3862 if (startpos < 0 || startpos > total_size)
3863 return -1;
3864
3865 /* Fix up RANGE if it might eventually take us outside
3866 the virtual concatenation of STRING1 and STRING2.
3867 Make sure we won't move STARTPOS below 0 or above TOTAL_SIZE. */
3868 if (endpos < 0)
3869 range = 0 - startpos;
3870 else if (endpos > total_size)
3871 range = total_size - startpos;
3872
3873 /* If the search isn't to be a backwards one, don't waste time in a
3874 search for a pattern anchored at beginning of buffer. */
3875 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == begbuf && range > 0)
3876 {
3877 if (startpos > 0)
3878 return -1;
3879 else
3880 range = 0;
3881 }
3882
3883 #ifdef emacs
3884 /* In a forward search for something that starts with \=.
3885 don't keep searching past point. */
3886 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == at_dot && range > 0)
3887 {
3888 range = PT_BYTE - BEGV_BYTE - startpos;
3889 if (range < 0)
3890 return -1;
3891 }
3892 #endif /* emacs */
3893
3894 /* Update the fastmap now if not correct already. */
3895 if (fastmap && !bufp->fastmap_accurate)
3896 re_compile_fastmap (bufp);
3897
3898 /* See whether the pattern is anchored. */
3899 anchored_start = (bufp->buffer[0] == begline);
3900
3901 #ifdef emacs
3902 gl_state.object = re_match_object;
3903 {
3904 int charpos = SYNTAX_TABLE_BYTE_TO_CHAR (POS_AS_IN_BUFFER (startpos));
3905
3906 SETUP_SYNTAX_TABLE_FOR_OBJECT (re_match_object, charpos, 1);
3907 }
3908 #endif
3909
3910 /* Loop through the string, looking for a place to start matching. */
3911 for (;;)
3912 {
3913 /* If the pattern is anchored,
3914 skip quickly past places we cannot match.
3915 We don't bother to treat startpos == 0 specially
3916 because that case doesn't repeat. */
3917 if (anchored_start && startpos > 0)
3918 {
3919 if (! ((startpos <= size1 ? string1[startpos - 1]
3920 : string2[startpos - size1 - 1])
3921 == '\n'))
3922 goto advance;
3923 }
3924
3925 /* If a fastmap is supplied, skip quickly over characters that
3926 cannot be the start of a match. If the pattern can match the
3927 null string, however, we don't need to skip characters; we want
3928 the first null string. */
3929 if (fastmap && startpos < total_size && !bufp->can_be_null)
3930 {
3931 register re_char *d;
3932 register re_wchar_t buf_ch;
3933
3934 d = POS_ADDR_VSTRING (startpos);
3935
3936 if (range > 0) /* Searching forwards. */
3937 {
3938 register int lim = 0;
3939 int irange = range;
3940
3941 if (startpos < size1 && startpos + range >= size1)
3942 lim = range - (size1 - startpos);
3943
3944 /* Written out as an if-else to avoid testing `translate'
3945 inside the loop. */
3946 if (RE_TRANSLATE_P (translate))
3947 {
3948 if (multibyte)
3949 while (range > lim)
3950 {
3951 int buf_charlen;
3952
3953 buf_ch = STRING_CHAR_AND_LENGTH (d, range - lim,
3954 buf_charlen);
3955
3956 buf_ch = RE_TRANSLATE (translate, buf_ch);
3957 if (buf_ch >= 0400
3958 || fastmap[buf_ch])
3959 break;
3960
3961 range -= buf_charlen;
3962 d += buf_charlen;
3963 }
3964 else
3965 while (range > lim
3966 && !fastmap[RE_TRANSLATE (translate, *d)])
3967 {
3968 d++;
3969 range--;
3970 }
3971 }
3972 else
3973 while (range > lim && !fastmap[*d])
3974 {
3975 d++;
3976 range--;
3977 }
3978
3979 startpos += irange - range;
3980 }
3981 else /* Searching backwards. */
3982 {
3983 int room = (startpos >= size1
3984 ? size2 + size1 - startpos
3985 : size1 - startpos);
3986 buf_ch = RE_STRING_CHAR (d, room);
3987 buf_ch = TRANSLATE (buf_ch);
3988
3989 if (! (buf_ch >= 0400
3990 || fastmap[buf_ch]))
3991 goto advance;
3992 }
3993 }
3994
3995 /* If can't match the null string, and that's all we have left, fail. */
3996 if (range >= 0 && startpos == total_size && fastmap
3997 && !bufp->can_be_null)
3998 return -1;
3999
4000 val = re_match_2_internal (bufp, string1, size1, string2, size2,
4001 startpos, regs, stop);
4002 #ifndef REGEX_MALLOC
4003 # ifdef C_ALLOCA
4004 alloca (0);
4005 # endif
4006 #endif
4007
4008 if (val >= 0)
4009 return startpos;
4010
4011 if (val == -2)
4012 return -2;
4013
4014 advance:
4015 if (!range)
4016 break;
4017 else if (range > 0)
4018 {
4019 /* Update STARTPOS to the next character boundary. */
4020 if (multibyte)
4021 {
4022 re_char *p = POS_ADDR_VSTRING (startpos);
4023 re_char *pend = STOP_ADDR_VSTRING (startpos);
4024 int len = MULTIBYTE_FORM_LENGTH (p, pend - p);
4025
4026 range -= len;
4027 if (range < 0)
4028 break;
4029 startpos += len;
4030 }
4031 else
4032 {
4033 range--;
4034 startpos++;
4035 }
4036 }
4037 else
4038 {
4039 range++;
4040 startpos--;
4041
4042 /* Update STARTPOS to the previous character boundary. */
4043 if (multibyte)
4044 {
4045 re_char *p = POS_ADDR_VSTRING (startpos);
4046 int len = 0;
4047
4048 /* Find the head of multibyte form. */
4049 while (!CHAR_HEAD_P (*p))
4050 p--, len++;
4051
4052 /* Adjust it. */
4053 #if 0 /* XXX */
4054 if (MULTIBYTE_FORM_LENGTH (p, len + 1) != (len + 1))
4055 ;
4056 else
4057 #endif
4058 {
4059 range += len;
4060 if (range > 0)
4061 break;
4062
4063 startpos -= len;
4064 }
4065 }
4066 }
4067 }
4068 return -1;
4069 } /* re_search_2 */
4070 WEAK_ALIAS (__re_search_2, re_search_2)
4071 \f
4072 /* Declarations and macros for re_match_2. */
4073
4074 static int bcmp_translate _RE_ARGS((re_char *s1, re_char *s2,
4075 register int len,
4076 RE_TRANSLATE_TYPE translate,
4077 const int multibyte));
4078
4079 /* This converts PTR, a pointer into one of the search strings `string1'
4080 and `string2' into an offset from the beginning of that string. */
4081 #define POINTER_TO_OFFSET(ptr) \
4082 (FIRST_STRING_P (ptr) \
4083 ? ((regoff_t) ((ptr) - string1)) \
4084 : ((regoff_t) ((ptr) - string2 + size1)))
4085
4086 /* Call before fetching a character with *d. This switches over to
4087 string2 if necessary.
4088 Check re_match_2_internal for a discussion of why end_match_2 might
4089 not be within string2 (but be equal to end_match_1 instead). */
4090 #define PREFETCH() \
4091 while (d == dend) \
4092 { \
4093 /* End of string2 => fail. */ \
4094 if (dend == end_match_2) \
4095 goto fail; \
4096 /* End of string1 => advance to string2. */ \
4097 d = string2; \
4098 dend = end_match_2; \
4099 }
4100
4101 /* Call before fetching a char with *d if you already checked other limits.
4102 This is meant for use in lookahead operations like wordend, etc..
4103 where we might need to look at parts of the string that might be
4104 outside of the LIMITs (i.e past `stop'). */
4105 #define PREFETCH_NOLIMIT() \
4106 if (d == end1) \
4107 { \
4108 d = string2; \
4109 dend = end_match_2; \
4110 } \
4111
4112 /* Test if at very beginning or at very end of the virtual concatenation
4113 of `string1' and `string2'. If only one string, it's `string2'. */
4114 #define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
4115 #define AT_STRINGS_END(d) ((d) == end2)
4116
4117
4118 /* Test if D points to a character which is word-constituent. We have
4119 two special cases to check for: if past the end of string1, look at
4120 the first character in string2; and if before the beginning of
4121 string2, look at the last character in string1. */
4122 #define WORDCHAR_P(d) \
4123 (SYNTAX ((d) == end1 ? *string2 \
4124 : (d) == string2 - 1 ? *(end1 - 1) : *(d)) \
4125 == Sword)
4126
4127 /* Disabled due to a compiler bug -- see comment at case wordbound */
4128
4129 /* The comment at case wordbound is following one, but we don't use
4130 AT_WORD_BOUNDARY anymore to support multibyte form.
4131
4132 The DEC Alpha C compiler 3.x generates incorrect code for the
4133 test WORDCHAR_P (d - 1) != WORDCHAR_P (d) in the expansion of
4134 AT_WORD_BOUNDARY, so this code is disabled. Expanding the
4135 macro and introducing temporary variables works around the bug. */
4136
4137 #if 0
4138 /* Test if the character before D and the one at D differ with respect
4139 to being word-constituent. */
4140 #define AT_WORD_BOUNDARY(d) \
4141 (AT_STRINGS_BEG (d) || AT_STRINGS_END (d) \
4142 || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
4143 #endif
4144
4145 /* Free everything we malloc. */
4146 #ifdef MATCH_MAY_ALLOCATE
4147 # define FREE_VAR(var) if (var) { REGEX_FREE (var); var = NULL; } else
4148 # define FREE_VARIABLES() \
4149 do { \
4150 REGEX_FREE_STACK (fail_stack.stack); \
4151 FREE_VAR (regstart); \
4152 FREE_VAR (regend); \
4153 FREE_VAR (best_regstart); \
4154 FREE_VAR (best_regend); \
4155 } while (0)
4156 #else
4157 # define FREE_VARIABLES() ((void)0) /* Do nothing! But inhibit gcc warning. */
4158 #endif /* not MATCH_MAY_ALLOCATE */
4159
4160 \f
4161 /* Optimization routines. */
4162
4163 /* If the operation is a match against one or more chars,
4164 return a pointer to the next operation, else return NULL. */
4165 static re_char *
4166 skip_one_char (p)
4167 re_char *p;
4168 {
4169 switch (SWITCH_ENUM_CAST (*p++))
4170 {
4171 case anychar:
4172 break;
4173
4174 case exactn:
4175 p += *p + 1;
4176 break;
4177
4178 case charset_not:
4179 case charset:
4180 if (CHARSET_RANGE_TABLE_EXISTS_P (p - 1))
4181 {
4182 int mcnt;
4183 p = CHARSET_RANGE_TABLE (p - 1);
4184 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4185 p = CHARSET_RANGE_TABLE_END (p, mcnt);
4186 }
4187 else
4188 p += 1 + CHARSET_BITMAP_SIZE (p - 1);
4189 break;
4190
4191 case syntaxspec:
4192 case notsyntaxspec:
4193 #ifdef emacs
4194 case categoryspec:
4195 case notcategoryspec:
4196 #endif /* emacs */
4197 p++;
4198 break;
4199
4200 default:
4201 p = NULL;
4202 }
4203 return p;
4204 }
4205
4206
4207 /* Jump over non-matching operations. */
4208 static unsigned char *
4209 skip_noops (p, pend)
4210 unsigned char *p, *pend;
4211 {
4212 int mcnt;
4213 while (p < pend)
4214 {
4215 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p))
4216 {
4217 case start_memory:
4218 case stop_memory:
4219 p += 2; break;
4220 case no_op:
4221 p += 1; break;
4222 case jump:
4223 p += 1;
4224 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4225 p += mcnt;
4226 break;
4227 default:
4228 return p;
4229 }
4230 }
4231 assert (p == pend);
4232 return p;
4233 }
4234
4235 /* Non-zero if "p1 matches something" implies "p2 fails". */
4236 static int
4237 mutually_exclusive_p (bufp, p1, p2)
4238 struct re_pattern_buffer *bufp;
4239 unsigned char *p1, *p2;
4240 {
4241 re_opcode_t op2;
4242 const boolean multibyte = RE_MULTIBYTE_P (bufp);
4243 unsigned char *pend = bufp->buffer + bufp->used;
4244
4245 assert (p1 >= bufp->buffer && p1 < pend
4246 && p2 >= bufp->buffer && p2 <= pend);
4247
4248 /* Skip over open/close-group commands.
4249 If what follows this loop is a ...+ construct,
4250 look at what begins its body, since we will have to
4251 match at least one of that. */
4252 p2 = skip_noops (p2, pend);
4253 /* The same skip can be done for p1, except that this function
4254 is only used in the case where p1 is a simple match operator. */
4255 /* p1 = skip_noops (p1, pend); */
4256
4257 assert (p1 >= bufp->buffer && p1 < pend
4258 && p2 >= bufp->buffer && p2 <= pend);
4259
4260 op2 = p2 == pend ? succeed : *p2;
4261
4262 switch (SWITCH_ENUM_CAST (op2))
4263 {
4264 case succeed:
4265 case endbuf:
4266 /* If we're at the end of the pattern, we can change. */
4267 if (skip_one_char (p1))
4268 {
4269 DEBUG_PRINT1 (" End of pattern: fast loop.\n");
4270 return 1;
4271 }
4272 break;
4273
4274 case endline:
4275 case exactn:
4276 {
4277 register re_wchar_t c
4278 = (re_opcode_t) *p2 == endline ? '\n'
4279 : RE_STRING_CHAR (p2 + 2, pend - p2 - 2);
4280
4281 if ((re_opcode_t) *p1 == exactn)
4282 {
4283 if (c != RE_STRING_CHAR (p1 + 2, pend - p1 - 2))
4284 {
4285 DEBUG_PRINT3 (" '%c' != '%c' => fast loop.\n", c, p1[2]);
4286 return 1;
4287 }
4288 }
4289
4290 else if ((re_opcode_t) *p1 == charset
4291 || (re_opcode_t) *p1 == charset_not)
4292 {
4293 int not = (re_opcode_t) *p1 == charset_not;
4294
4295 /* Test if C is listed in charset (or charset_not)
4296 at `p1'. */
4297 if (SINGLE_BYTE_CHAR_P (c))
4298 {
4299 if (c < CHARSET_BITMAP_SIZE (p1) * BYTEWIDTH
4300 && p1[2 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4301 not = !not;
4302 }
4303 else if (CHARSET_RANGE_TABLE_EXISTS_P (p1))
4304 CHARSET_LOOKUP_RANGE_TABLE (not, c, p1);
4305
4306 /* `not' is equal to 1 if c would match, which means
4307 that we can't change to pop_failure_jump. */
4308 if (!not)
4309 {
4310 DEBUG_PRINT1 (" No match => fast loop.\n");
4311 return 1;
4312 }
4313 }
4314 else if ((re_opcode_t) *p1 == anychar
4315 && c == '\n')
4316 {
4317 DEBUG_PRINT1 (" . != \\n => fast loop.\n");
4318 return 1;
4319 }
4320 }
4321 break;
4322
4323 case charset:
4324 {
4325 if ((re_opcode_t) *p1 == exactn)
4326 /* Reuse the code above. */
4327 return mutually_exclusive_p (bufp, p2, p1);
4328
4329 /* It is hard to list up all the character in charset
4330 P2 if it includes multibyte character. Give up in
4331 such case. */
4332 else if (!multibyte || !CHARSET_RANGE_TABLE_EXISTS_P (p2))
4333 {
4334 /* Now, we are sure that P2 has no range table.
4335 So, for the size of bitmap in P2, `p2[1]' is
4336 enough. But P1 may have range table, so the
4337 size of bitmap table of P1 is extracted by
4338 using macro `CHARSET_BITMAP_SIZE'.
4339
4340 Since we know that all the character listed in
4341 P2 is ASCII, it is enough to test only bitmap
4342 table of P1. */
4343
4344 if ((re_opcode_t) *p1 == charset)
4345 {
4346 int idx;
4347 /* We win if the charset inside the loop
4348 has no overlap with the one after the loop. */
4349 for (idx = 0;
4350 (idx < (int) p2[1]
4351 && idx < CHARSET_BITMAP_SIZE (p1));
4352 idx++)
4353 if ((p2[2 + idx] & p1[2 + idx]) != 0)
4354 break;
4355
4356 if (idx == p2[1]
4357 || idx == CHARSET_BITMAP_SIZE (p1))
4358 {
4359 DEBUG_PRINT1 (" No match => fast loop.\n");
4360 return 1;
4361 }
4362 }
4363 else if ((re_opcode_t) *p1 == charset_not)
4364 {
4365 int idx;
4366 /* We win if the charset_not inside the loop lists
4367 every character listed in the charset after. */
4368 for (idx = 0; idx < (int) p2[1]; idx++)
4369 if (! (p2[2 + idx] == 0
4370 || (idx < CHARSET_BITMAP_SIZE (p1)
4371 && ((p2[2 + idx] & ~ p1[2 + idx]) == 0))))
4372 break;
4373
4374 if (idx == p2[1])
4375 {
4376 DEBUG_PRINT1 (" No match => fast loop.\n");
4377 return 1;
4378 }
4379 }
4380 }
4381 }
4382 break;
4383
4384 case charset_not:
4385 switch (SWITCH_ENUM_CAST (*p1))
4386 {
4387 case exactn:
4388 case charset:
4389 /* Reuse the code above. */
4390 return mutually_exclusive_p (bufp, p2, p1);
4391 case charset_not:
4392 /* When we have two charset_not, it's very unlikely that
4393 they don't overlap. The union of the two sets of excluded
4394 chars should cover all possible chars, which, as a matter of
4395 fact, is virtually impossible in multibyte buffers. */
4396 ;
4397 }
4398 break;
4399
4400 case wordend:
4401 case notsyntaxspec:
4402 return ((re_opcode_t) *p1 == syntaxspec
4403 && p1[1] == (op2 == wordend ? Sword : p2[1]));
4404
4405 case wordbeg:
4406 case syntaxspec:
4407 return ((re_opcode_t) *p1 == notsyntaxspec
4408 && p1[1] == (op2 == wordend ? Sword : p2[1]));
4409
4410 case wordbound:
4411 return (((re_opcode_t) *p1 == notsyntaxspec
4412 || (re_opcode_t) *p1 == syntaxspec)
4413 && p1[1] == Sword);
4414
4415 #ifdef emacs
4416 case categoryspec:
4417 return ((re_opcode_t) *p1 == notcategoryspec && p1[1] == p2[1]);
4418 case notcategoryspec:
4419 return ((re_opcode_t) *p1 == categoryspec && p1[1] == p2[1]);
4420 #endif /* emacs */
4421
4422 default:
4423 ;
4424 }
4425
4426 /* Safe default. */
4427 return 0;
4428 }
4429
4430 \f
4431 /* Matching routines. */
4432
4433 #ifndef emacs /* Emacs never uses this. */
4434 /* re_match is like re_match_2 except it takes only a single string. */
4435
4436 int
4437 re_match (bufp, string, size, pos, regs)
4438 struct re_pattern_buffer *bufp;
4439 const char *string;
4440 int size, pos;
4441 struct re_registers *regs;
4442 {
4443 int result = re_match_2_internal (bufp, NULL, 0, (re_char*) string, size,
4444 pos, regs, size);
4445 # if defined C_ALLOCA && !defined REGEX_MALLOC
4446 alloca (0);
4447 # endif
4448 return result;
4449 }
4450 WEAK_ALIAS (__re_match, re_match)
4451 #endif /* not emacs */
4452
4453 #ifdef emacs
4454 /* In Emacs, this is the string or buffer in which we
4455 are matching. It is used for looking up syntax properties. */
4456 Lisp_Object re_match_object;
4457 #endif
4458
4459 /* re_match_2 matches the compiled pattern in BUFP against the
4460 the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
4461 and SIZE2, respectively). We start matching at POS, and stop
4462 matching at STOP.
4463
4464 If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
4465 store offsets for the substring each group matched in REGS. See the
4466 documentation for exactly how many groups we fill.
4467
4468 We return -1 if no match, -2 if an internal error (such as the
4469 failure stack overflowing). Otherwise, we return the length of the
4470 matched substring. */
4471
4472 int
4473 re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
4474 struct re_pattern_buffer *bufp;
4475 const char *string1, *string2;
4476 int size1, size2;
4477 int pos;
4478 struct re_registers *regs;
4479 int stop;
4480 {
4481 int result;
4482
4483 #ifdef emacs
4484 int charpos;
4485 gl_state.object = re_match_object;
4486 charpos = SYNTAX_TABLE_BYTE_TO_CHAR (POS_AS_IN_BUFFER (pos));
4487 SETUP_SYNTAX_TABLE_FOR_OBJECT (re_match_object, charpos, 1);
4488 #endif
4489
4490 result = re_match_2_internal (bufp, (re_char*) string1, size1,
4491 (re_char*) string2, size2,
4492 pos, regs, stop);
4493 #if defined C_ALLOCA && !defined REGEX_MALLOC
4494 alloca (0);
4495 #endif
4496 return result;
4497 }
4498 WEAK_ALIAS (__re_match_2, re_match_2)
4499
4500 /* This is a separate function so that we can force an alloca cleanup
4501 afterwards. */
4502 static int
4503 re_match_2_internal (bufp, string1, size1, string2, size2, pos, regs, stop)
4504 struct re_pattern_buffer *bufp;
4505 re_char *string1, *string2;
4506 int size1, size2;
4507 int pos;
4508 struct re_registers *regs;
4509 int stop;
4510 {
4511 /* General temporaries. */
4512 int mcnt;
4513 size_t reg;
4514 boolean not;
4515
4516 /* Just past the end of the corresponding string. */
4517 re_char *end1, *end2;
4518
4519 /* Pointers into string1 and string2, just past the last characters in
4520 each to consider matching. */
4521 re_char *end_match_1, *end_match_2;
4522
4523 /* Where we are in the data, and the end of the current string. */
4524 re_char *d, *dend;
4525
4526 /* Used sometimes to remember where we were before starting matching
4527 an operator so that we can go back in case of failure. This "atomic"
4528 behavior of matching opcodes is indispensable to the correctness
4529 of the on_failure_keep_string_jump optimization. */
4530 re_char *dfail;
4531
4532 /* Where we are in the pattern, and the end of the pattern. */
4533 re_char *p = bufp->buffer;
4534 re_char *pend = p + bufp->used;
4535
4536 /* We use this to map every character in the string. */
4537 RE_TRANSLATE_TYPE translate = bufp->translate;
4538
4539 /* Nonzero if we have to concern multibyte character. */
4540 const boolean multibyte = RE_MULTIBYTE_P (bufp);
4541
4542 /* Failure point stack. Each place that can handle a failure further
4543 down the line pushes a failure point on this stack. It consists of
4544 regstart, and regend for all registers corresponding to
4545 the subexpressions we're currently inside, plus the number of such
4546 registers, and, finally, two char *'s. The first char * is where
4547 to resume scanning the pattern; the second one is where to resume
4548 scanning the strings. */
4549 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
4550 fail_stack_type fail_stack;
4551 #endif
4552 #ifdef DEBUG
4553 unsigned nfailure_points_pushed = 0, nfailure_points_popped = 0;
4554 #endif
4555
4556 #if defined REL_ALLOC && defined REGEX_MALLOC
4557 /* This holds the pointer to the failure stack, when
4558 it is allocated relocatably. */
4559 fail_stack_elt_t *failure_stack_ptr;
4560 #endif
4561
4562 /* We fill all the registers internally, independent of what we
4563 return, for use in backreferences. The number here includes
4564 an element for register zero. */
4565 size_t num_regs = bufp->re_nsub + 1;
4566
4567 /* Information on the contents of registers. These are pointers into
4568 the input strings; they record just what was matched (on this
4569 attempt) by a subexpression part of the pattern, that is, the
4570 regnum-th regstart pointer points to where in the pattern we began
4571 matching and the regnum-th regend points to right after where we
4572 stopped matching the regnum-th subexpression. (The zeroth register
4573 keeps track of what the whole pattern matches.) */
4574 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
4575 re_char **regstart, **regend;
4576 #endif
4577
4578 /* The following record the register info as found in the above
4579 variables when we find a match better than any we've seen before.
4580 This happens as we backtrack through the failure points, which in
4581 turn happens only if we have not yet matched the entire string. */
4582 unsigned best_regs_set = false;
4583 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
4584 re_char **best_regstart, **best_regend;
4585 #endif
4586
4587 /* Logically, this is `best_regend[0]'. But we don't want to have to
4588 allocate space for that if we're not allocating space for anything
4589 else (see below). Also, we never need info about register 0 for
4590 any of the other register vectors, and it seems rather a kludge to
4591 treat `best_regend' differently than the rest. So we keep track of
4592 the end of the best match so far in a separate variable. We
4593 initialize this to NULL so that when we backtrack the first time
4594 and need to test it, it's not garbage. */
4595 re_char *match_end = NULL;
4596
4597 #ifdef DEBUG
4598 /* Counts the total number of registers pushed. */
4599 unsigned num_regs_pushed = 0;
4600 #endif
4601
4602 DEBUG_PRINT1 ("\n\nEntering re_match_2.\n");
4603
4604 INIT_FAIL_STACK ();
4605
4606 #ifdef MATCH_MAY_ALLOCATE
4607 /* Do not bother to initialize all the register variables if there are
4608 no groups in the pattern, as it takes a fair amount of time. If
4609 there are groups, we include space for register 0 (the whole
4610 pattern), even though we never use it, since it simplifies the
4611 array indexing. We should fix this. */
4612 if (bufp->re_nsub)
4613 {
4614 regstart = REGEX_TALLOC (num_regs, re_char *);
4615 regend = REGEX_TALLOC (num_regs, re_char *);
4616 best_regstart = REGEX_TALLOC (num_regs, re_char *);
4617 best_regend = REGEX_TALLOC (num_regs, re_char *);
4618
4619 if (!(regstart && regend && best_regstart && best_regend))
4620 {
4621 FREE_VARIABLES ();
4622 return -2;
4623 }
4624 }
4625 else
4626 {
4627 /* We must initialize all our variables to NULL, so that
4628 `FREE_VARIABLES' doesn't try to free them. */
4629 regstart = regend = best_regstart = best_regend = NULL;
4630 }
4631 #endif /* MATCH_MAY_ALLOCATE */
4632
4633 /* The starting position is bogus. */
4634 if (pos < 0 || pos > size1 + size2)
4635 {
4636 FREE_VARIABLES ();
4637 return -1;
4638 }
4639
4640 /* Initialize subexpression text positions to -1 to mark ones that no
4641 start_memory/stop_memory has been seen for. Also initialize the
4642 register information struct. */
4643 for (reg = 1; reg < num_regs; reg++)
4644 regstart[reg] = regend[reg] = NULL;
4645
4646 /* We move `string1' into `string2' if the latter's empty -- but not if
4647 `string1' is null. */
4648 if (size2 == 0 && string1 != NULL)
4649 {
4650 string2 = string1;
4651 size2 = size1;
4652 string1 = 0;
4653 size1 = 0;
4654 }
4655 end1 = string1 + size1;
4656 end2 = string2 + size2;
4657
4658 /* `p' scans through the pattern as `d' scans through the data.
4659 `dend' is the end of the input string that `d' points within. `d'
4660 is advanced into the following input string whenever necessary, but
4661 this happens before fetching; therefore, at the beginning of the
4662 loop, `d' can be pointing at the end of a string, but it cannot
4663 equal `string2'. */
4664 if (pos >= size1)
4665 {
4666 /* Only match within string2. */
4667 d = string2 + pos - size1;
4668 dend = end_match_2 = string2 + stop - size1;
4669 end_match_1 = end1; /* Just to give it a value. */
4670 }
4671 else
4672 {
4673 if (stop < size1)
4674 {
4675 /* Only match within string1. */
4676 end_match_1 = string1 + stop;
4677 /* BEWARE!
4678 When we reach end_match_1, PREFETCH normally switches to string2.
4679 But in the present case, this means that just doing a PREFETCH
4680 makes us jump from `stop' to `gap' within the string.
4681 What we really want here is for the search to stop as
4682 soon as we hit end_match_1. That's why we set end_match_2
4683 to end_match_1 (since PREFETCH fails as soon as we hit
4684 end_match_2). */
4685 end_match_2 = end_match_1;
4686 }
4687 else
4688 { /* It's important to use this code when stop == size so that
4689 moving `d' from end1 to string2 will not prevent the d == dend
4690 check from catching the end of string. */
4691 end_match_1 = end1;
4692 end_match_2 = string2 + stop - size1;
4693 }
4694 d = string1 + pos;
4695 dend = end_match_1;
4696 }
4697
4698 DEBUG_PRINT1 ("The compiled pattern is: ");
4699 DEBUG_PRINT_COMPILED_PATTERN (bufp, p, pend);
4700 DEBUG_PRINT1 ("The string to match is: `");
4701 DEBUG_PRINT_DOUBLE_STRING (d, string1, size1, string2, size2);
4702 DEBUG_PRINT1 ("'\n");
4703
4704 /* This loops over pattern commands. It exits by returning from the
4705 function if the match is complete, or it drops through if the match
4706 fails at this starting point in the input data. */
4707 for (;;)
4708 {
4709 DEBUG_PRINT2 ("\n%p: ", p);
4710
4711 if (p == pend)
4712 { /* End of pattern means we might have succeeded. */
4713 DEBUG_PRINT1 ("end of pattern ... ");
4714
4715 /* If we haven't matched the entire string, and we want the
4716 longest match, try backtracking. */
4717 if (d != end_match_2)
4718 {
4719 /* 1 if this match ends in the same string (string1 or string2)
4720 as the best previous match. */
4721 boolean same_str_p = (FIRST_STRING_P (match_end)
4722 == FIRST_STRING_P (d));
4723 /* 1 if this match is the best seen so far. */
4724 boolean best_match_p;
4725
4726 /* AIX compiler got confused when this was combined
4727 with the previous declaration. */
4728 if (same_str_p)
4729 best_match_p = d > match_end;
4730 else
4731 best_match_p = !FIRST_STRING_P (d);
4732
4733 DEBUG_PRINT1 ("backtracking.\n");
4734
4735 if (!FAIL_STACK_EMPTY ())
4736 { /* More failure points to try. */
4737
4738 /* If exceeds best match so far, save it. */
4739 if (!best_regs_set || best_match_p)
4740 {
4741 best_regs_set = true;
4742 match_end = d;
4743
4744 DEBUG_PRINT1 ("\nSAVING match as best so far.\n");
4745
4746 for (reg = 1; reg < num_regs; reg++)
4747 {
4748 best_regstart[reg] = regstart[reg];
4749 best_regend[reg] = regend[reg];
4750 }
4751 }
4752 goto fail;
4753 }
4754
4755 /* If no failure points, don't restore garbage. And if
4756 last match is real best match, don't restore second
4757 best one. */
4758 else if (best_regs_set && !best_match_p)
4759 {
4760 restore_best_regs:
4761 /* Restore best match. It may happen that `dend ==
4762 end_match_1' while the restored d is in string2.
4763 For example, the pattern `x.*y.*z' against the
4764 strings `x-' and `y-z-', if the two strings are
4765 not consecutive in memory. */
4766 DEBUG_PRINT1 ("Restoring best registers.\n");
4767
4768 d = match_end;
4769 dend = ((d >= string1 && d <= end1)
4770 ? end_match_1 : end_match_2);
4771
4772 for (reg = 1; reg < num_regs; reg++)
4773 {
4774 regstart[reg] = best_regstart[reg];
4775 regend[reg] = best_regend[reg];
4776 }
4777 }
4778 } /* d != end_match_2 */
4779
4780 succeed_label:
4781 DEBUG_PRINT1 ("Accepting match.\n");
4782
4783 /* If caller wants register contents data back, do it. */
4784 if (regs && !bufp->no_sub)
4785 {
4786 /* Have the register data arrays been allocated? */
4787 if (bufp->regs_allocated == REGS_UNALLOCATED)
4788 { /* No. So allocate them with malloc. We need one
4789 extra element beyond `num_regs' for the `-1' marker
4790 GNU code uses. */
4791 regs->num_regs = MAX (RE_NREGS, num_regs + 1);
4792 regs->start = TALLOC (regs->num_regs, regoff_t);
4793 regs->end = TALLOC (regs->num_regs, regoff_t);
4794 if (regs->start == NULL || regs->end == NULL)
4795 {
4796 FREE_VARIABLES ();
4797 return -2;
4798 }
4799 bufp->regs_allocated = REGS_REALLOCATE;
4800 }
4801 else if (bufp->regs_allocated == REGS_REALLOCATE)
4802 { /* Yes. If we need more elements than were already
4803 allocated, reallocate them. If we need fewer, just
4804 leave it alone. */
4805 if (regs->num_regs < num_regs + 1)
4806 {
4807 regs->num_regs = num_regs + 1;
4808 RETALLOC (regs->start, regs->num_regs, regoff_t);
4809 RETALLOC (regs->end, regs->num_regs, regoff_t);
4810 if (regs->start == NULL || regs->end == NULL)
4811 {
4812 FREE_VARIABLES ();
4813 return -2;
4814 }
4815 }
4816 }
4817 else
4818 {
4819 /* These braces fend off a "empty body in an else-statement"
4820 warning under GCC when assert expands to nothing. */
4821 assert (bufp->regs_allocated == REGS_FIXED);
4822 }
4823
4824 /* Convert the pointer data in `regstart' and `regend' to
4825 indices. Register zero has to be set differently,
4826 since we haven't kept track of any info for it. */
4827 if (regs->num_regs > 0)
4828 {
4829 regs->start[0] = pos;
4830 regs->end[0] = POINTER_TO_OFFSET (d);
4831 }
4832
4833 /* Go through the first `min (num_regs, regs->num_regs)'
4834 registers, since that is all we initialized. */
4835 for (reg = 1; reg < MIN (num_regs, regs->num_regs); reg++)
4836 {
4837 if (REG_UNSET (regstart[reg]) || REG_UNSET (regend[reg]))
4838 regs->start[reg] = regs->end[reg] = -1;
4839 else
4840 {
4841 regs->start[reg]
4842 = (regoff_t) POINTER_TO_OFFSET (regstart[reg]);
4843 regs->end[reg]
4844 = (regoff_t) POINTER_TO_OFFSET (regend[reg]);
4845 }
4846 }
4847
4848 /* If the regs structure we return has more elements than
4849 were in the pattern, set the extra elements to -1. If
4850 we (re)allocated the registers, this is the case,
4851 because we always allocate enough to have at least one
4852 -1 at the end. */
4853 for (reg = num_regs; reg < regs->num_regs; reg++)
4854 regs->start[reg] = regs->end[reg] = -1;
4855 } /* regs && !bufp->no_sub */
4856
4857 DEBUG_PRINT4 ("%u failure points pushed, %u popped (%u remain).\n",
4858 nfailure_points_pushed, nfailure_points_popped,
4859 nfailure_points_pushed - nfailure_points_popped);
4860 DEBUG_PRINT2 ("%u registers pushed.\n", num_regs_pushed);
4861
4862 mcnt = POINTER_TO_OFFSET (d) - pos;
4863
4864 DEBUG_PRINT2 ("Returning %d from re_match_2.\n", mcnt);
4865
4866 FREE_VARIABLES ();
4867 return mcnt;
4868 }
4869
4870 /* Otherwise match next pattern command. */
4871 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
4872 {
4873 /* Ignore these. Used to ignore the n of succeed_n's which
4874 currently have n == 0. */
4875 case no_op:
4876 DEBUG_PRINT1 ("EXECUTING no_op.\n");
4877 break;
4878
4879 case succeed:
4880 DEBUG_PRINT1 ("EXECUTING succeed.\n");
4881 goto succeed_label;
4882
4883 /* Match the next n pattern characters exactly. The following
4884 byte in the pattern defines n, and the n bytes after that
4885 are the characters to match. */
4886 case exactn:
4887 mcnt = *p++;
4888 DEBUG_PRINT2 ("EXECUTING exactn %d.\n", mcnt);
4889
4890 /* Remember the start point to rollback upon failure. */
4891 dfail = d;
4892
4893 /* This is written out as an if-else so we don't waste time
4894 testing `translate' inside the loop. */
4895 if (RE_TRANSLATE_P (translate))
4896 {
4897 if (multibyte)
4898 do
4899 {
4900 int pat_charlen, buf_charlen;
4901 unsigned int pat_ch, buf_ch;
4902
4903 PREFETCH ();
4904 pat_ch = STRING_CHAR_AND_LENGTH (p, pend - p, pat_charlen);
4905 buf_ch = STRING_CHAR_AND_LENGTH (d, dend - d, buf_charlen);
4906
4907 if (RE_TRANSLATE (translate, buf_ch)
4908 != pat_ch)
4909 {
4910 d = dfail;
4911 goto fail;
4912 }
4913
4914 p += pat_charlen;
4915 d += buf_charlen;
4916 mcnt -= pat_charlen;
4917 }
4918 while (mcnt > 0);
4919 else
4920 do
4921 {
4922 PREFETCH ();
4923 if (RE_TRANSLATE (translate, *d) != *p++)
4924 {
4925 d = dfail;
4926 goto fail;
4927 }
4928 d++;
4929 }
4930 while (--mcnt);
4931 }
4932 else
4933 {
4934 do
4935 {
4936 PREFETCH ();
4937 if (*d++ != *p++)
4938 {
4939 d = dfail;
4940 goto fail;
4941 }
4942 }
4943 while (--mcnt);
4944 }
4945 break;
4946
4947
4948 /* Match any character except possibly a newline or a null. */
4949 case anychar:
4950 {
4951 int buf_charlen;
4952 re_wchar_t buf_ch;
4953
4954 DEBUG_PRINT1 ("EXECUTING anychar.\n");
4955
4956 PREFETCH ();
4957 buf_ch = RE_STRING_CHAR_AND_LENGTH (d, dend - d, buf_charlen);
4958 buf_ch = TRANSLATE (buf_ch);
4959
4960 if ((!(bufp->syntax & RE_DOT_NEWLINE)
4961 && buf_ch == '\n')
4962 || ((bufp->syntax & RE_DOT_NOT_NULL)
4963 && buf_ch == '\000'))
4964 goto fail;
4965
4966 DEBUG_PRINT2 (" Matched `%d'.\n", *d);
4967 d += buf_charlen;
4968 }
4969 break;
4970
4971
4972 case charset:
4973 case charset_not:
4974 {
4975 register unsigned int c;
4976 boolean not = (re_opcode_t) *(p - 1) == charset_not;
4977 int len;
4978
4979 /* Start of actual range_table, or end of bitmap if there is no
4980 range table. */
4981 re_char *range_table;
4982
4983 /* Nonzero if there is a range table. */
4984 int range_table_exists;
4985
4986 /* Number of ranges of range table. This is not included
4987 in the initial byte-length of the command. */
4988 int count = 0;
4989
4990 DEBUG_PRINT2 ("EXECUTING charset%s.\n", not ? "_not" : "");
4991
4992 range_table_exists = CHARSET_RANGE_TABLE_EXISTS_P (&p[-1]);
4993
4994 if (range_table_exists)
4995 {
4996 range_table = CHARSET_RANGE_TABLE (&p[-1]); /* Past the bitmap. */
4997 EXTRACT_NUMBER_AND_INCR (count, range_table);
4998 }
4999
5000 PREFETCH ();
5001 c = RE_STRING_CHAR_AND_LENGTH (d, dend - d, len);
5002 c = TRANSLATE (c); /* The character to match. */
5003
5004 if (SINGLE_BYTE_CHAR_P (c))
5005 { /* Lookup bitmap. */
5006 /* Cast to `unsigned' instead of `unsigned char' in
5007 case the bit list is a full 32 bytes long. */
5008 if (c < (unsigned) (CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH)
5009 && p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
5010 not = !not;
5011 }
5012 #ifdef emacs
5013 else if (range_table_exists)
5014 {
5015 int class_bits = CHARSET_RANGE_TABLE_BITS (&p[-1]);
5016
5017 if ( (class_bits & BIT_LOWER && ISLOWER (c))
5018 | (class_bits & BIT_MULTIBYTE)
5019 | (class_bits & BIT_PUNCT && ISPUNCT (c))
5020 | (class_bits & BIT_SPACE && ISSPACE (c))
5021 | (class_bits & BIT_UPPER && ISUPPER (c))
5022 | (class_bits & BIT_WORD && ISWORD (c)))
5023 not = !not;
5024 else
5025 CHARSET_LOOKUP_RANGE_TABLE_RAW (not, c, range_table, count);
5026 }
5027 #endif /* emacs */
5028
5029 if (range_table_exists)
5030 p = CHARSET_RANGE_TABLE_END (range_table, count);
5031 else
5032 p += CHARSET_BITMAP_SIZE (&p[-1]) + 1;
5033
5034 if (!not) goto fail;
5035
5036 d += len;
5037 break;
5038 }
5039
5040
5041 /* The beginning of a group is represented by start_memory.
5042 The argument is the register number. The text
5043 matched within the group is recorded (in the internal
5044 registers data structure) under the register number. */
5045 case start_memory:
5046 DEBUG_PRINT2 ("EXECUTING start_memory %d:\n", *p);
5047
5048 /* In case we need to undo this operation (via backtracking). */
5049 PUSH_FAILURE_REG ((unsigned int)*p);
5050
5051 regstart[*p] = d;
5052 regend[*p] = NULL; /* probably unnecessary. -sm */
5053 DEBUG_PRINT2 (" regstart: %d\n", POINTER_TO_OFFSET (regstart[*p]));
5054
5055 /* Move past the register number and inner group count. */
5056 p += 1;
5057 break;
5058
5059
5060 /* The stop_memory opcode represents the end of a group. Its
5061 argument is the same as start_memory's: the register number. */
5062 case stop_memory:
5063 DEBUG_PRINT2 ("EXECUTING stop_memory %d:\n", *p);
5064
5065 assert (!REG_UNSET (regstart[*p]));
5066 /* Strictly speaking, there should be code such as:
5067
5068 assert (REG_UNSET (regend[*p]));
5069 PUSH_FAILURE_REGSTOP ((unsigned int)*p);
5070
5071 But the only info to be pushed is regend[*p] and it is known to
5072 be UNSET, so there really isn't anything to push.
5073 Not pushing anything, on the other hand deprives us from the
5074 guarantee that regend[*p] is UNSET since undoing this operation
5075 will not reset its value properly. This is not important since
5076 the value will only be read on the next start_memory or at
5077 the very end and both events can only happen if this stop_memory
5078 is *not* undone. */
5079
5080 regend[*p] = d;
5081 DEBUG_PRINT2 (" regend: %d\n", POINTER_TO_OFFSET (regend[*p]));
5082
5083 /* Move past the register number and the inner group count. */
5084 p += 1;
5085 break;
5086
5087
5088 /* \<digit> has been turned into a `duplicate' command which is
5089 followed by the numeric value of <digit> as the register number. */
5090 case duplicate:
5091 {
5092 register re_char *d2, *dend2;
5093 int regno = *p++; /* Get which register to match against. */
5094 DEBUG_PRINT2 ("EXECUTING duplicate %d.\n", regno);
5095
5096 /* Can't back reference a group which we've never matched. */
5097 if (REG_UNSET (regstart[regno]) || REG_UNSET (regend[regno]))
5098 goto fail;
5099
5100 /* Where in input to try to start matching. */
5101 d2 = regstart[regno];
5102
5103 /* Remember the start point to rollback upon failure. */
5104 dfail = d;
5105
5106 /* Where to stop matching; if both the place to start and
5107 the place to stop matching are in the same string, then
5108 set to the place to stop, otherwise, for now have to use
5109 the end of the first string. */
5110
5111 dend2 = ((FIRST_STRING_P (regstart[regno])
5112 == FIRST_STRING_P (regend[regno]))
5113 ? regend[regno] : end_match_1);
5114 for (;;)
5115 {
5116 /* If necessary, advance to next segment in register
5117 contents. */
5118 while (d2 == dend2)
5119 {
5120 if (dend2 == end_match_2) break;
5121 if (dend2 == regend[regno]) break;
5122
5123 /* End of string1 => advance to string2. */
5124 d2 = string2;
5125 dend2 = regend[regno];
5126 }
5127 /* At end of register contents => success */
5128 if (d2 == dend2) break;
5129
5130 /* If necessary, advance to next segment in data. */
5131 PREFETCH ();
5132
5133 /* How many characters left in this segment to match. */
5134 mcnt = dend - d;
5135
5136 /* Want how many consecutive characters we can match in
5137 one shot, so, if necessary, adjust the count. */
5138 if (mcnt > dend2 - d2)
5139 mcnt = dend2 - d2;
5140
5141 /* Compare that many; failure if mismatch, else move
5142 past them. */
5143 if (RE_TRANSLATE_P (translate)
5144 ? bcmp_translate (d, d2, mcnt, translate, multibyte)
5145 : memcmp (d, d2, mcnt))
5146 {
5147 d = dfail;
5148 goto fail;
5149 }
5150 d += mcnt, d2 += mcnt;
5151 }
5152 }
5153 break;
5154
5155
5156 /* begline matches the empty string at the beginning of the string
5157 (unless `not_bol' is set in `bufp'), and after newlines. */
5158 case begline:
5159 DEBUG_PRINT1 ("EXECUTING begline.\n");
5160
5161 if (AT_STRINGS_BEG (d))
5162 {
5163 if (!bufp->not_bol) break;
5164 }
5165 else
5166 {
5167 unsigned char c;
5168 GET_CHAR_BEFORE_2 (c, d, string1, end1, string2, end2);
5169 if (c == '\n')
5170 break;
5171 }
5172 /* In all other cases, we fail. */
5173 goto fail;
5174
5175
5176 /* endline is the dual of begline. */
5177 case endline:
5178 DEBUG_PRINT1 ("EXECUTING endline.\n");
5179
5180 if (AT_STRINGS_END (d))
5181 {
5182 if (!bufp->not_eol) break;
5183 }
5184 else
5185 {
5186 PREFETCH_NOLIMIT ();
5187 if (*d == '\n')
5188 break;
5189 }
5190 goto fail;
5191
5192
5193 /* Match at the very beginning of the data. */
5194 case begbuf:
5195 DEBUG_PRINT1 ("EXECUTING begbuf.\n");
5196 if (AT_STRINGS_BEG (d))
5197 break;
5198 goto fail;
5199
5200
5201 /* Match at the very end of the data. */
5202 case endbuf:
5203 DEBUG_PRINT1 ("EXECUTING endbuf.\n");
5204 if (AT_STRINGS_END (d))
5205 break;
5206 goto fail;
5207
5208
5209 /* on_failure_keep_string_jump is used to optimize `.*\n'. It
5210 pushes NULL as the value for the string on the stack. Then
5211 `POP_FAILURE_POINT' will keep the current value for the
5212 string, instead of restoring it. To see why, consider
5213 matching `foo\nbar' against `.*\n'. The .* matches the foo;
5214 then the . fails against the \n. But the next thing we want
5215 to do is match the \n against the \n; if we restored the
5216 string value, we would be back at the foo.
5217
5218 Because this is used only in specific cases, we don't need to
5219 check all the things that `on_failure_jump' does, to make
5220 sure the right things get saved on the stack. Hence we don't
5221 share its code. The only reason to push anything on the
5222 stack at all is that otherwise we would have to change
5223 `anychar's code to do something besides goto fail in this
5224 case; that seems worse than this. */
5225 case on_failure_keep_string_jump:
5226 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5227 DEBUG_PRINT3 ("EXECUTING on_failure_keep_string_jump %d (to %p):\n",
5228 mcnt, p + mcnt);
5229
5230 PUSH_FAILURE_POINT (p - 3, NULL);
5231 break;
5232
5233 /* A nasty loop is introduced by the non-greedy *? and +?.
5234 With such loops, the stack only ever contains one failure point
5235 at a time, so that a plain on_failure_jump_loop kind of
5236 cycle detection cannot work. Worse yet, such a detection
5237 can not only fail to detect a cycle, but it can also wrongly
5238 detect a cycle (between different instantiations of the same
5239 loop.
5240 So the method used for those nasty loops is a little different:
5241 We use a special cycle-detection-stack-frame which is pushed
5242 when the on_failure_jump_nastyloop failure-point is *popped*.
5243 This special frame thus marks the beginning of one iteration
5244 through the loop and we can hence easily check right here
5245 whether something matched between the beginning and the end of
5246 the loop. */
5247 case on_failure_jump_nastyloop:
5248 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5249 DEBUG_PRINT3 ("EXECUTING on_failure_jump_nastyloop %d (to %p):\n",
5250 mcnt, p + mcnt);
5251
5252 assert ((re_opcode_t)p[-4] == no_op);
5253 CHECK_INFINITE_LOOP (p - 4, d);
5254 PUSH_FAILURE_POINT (p - 3, d);
5255 break;
5256
5257
5258 /* Simple loop detecting on_failure_jump: just check on the
5259 failure stack if the same spot was already hit earlier. */
5260 case on_failure_jump_loop:
5261 on_failure:
5262 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5263 DEBUG_PRINT3 ("EXECUTING on_failure_jump_loop %d (to %p):\n",
5264 mcnt, p + mcnt);
5265
5266 CHECK_INFINITE_LOOP (p - 3, d);
5267 PUSH_FAILURE_POINT (p - 3, d);
5268 break;
5269
5270
5271 /* Uses of on_failure_jump:
5272
5273 Each alternative starts with an on_failure_jump that points
5274 to the beginning of the next alternative. Each alternative
5275 except the last ends with a jump that in effect jumps past
5276 the rest of the alternatives. (They really jump to the
5277 ending jump of the following alternative, because tensioning
5278 these jumps is a hassle.)
5279
5280 Repeats start with an on_failure_jump that points past both
5281 the repetition text and either the following jump or
5282 pop_failure_jump back to this on_failure_jump. */
5283 case on_failure_jump:
5284 IMMEDIATE_QUIT_CHECK;
5285 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5286 DEBUG_PRINT3 ("EXECUTING on_failure_jump %d (to %p):\n",
5287 mcnt, p + mcnt);
5288
5289 PUSH_FAILURE_POINT (p -3, d);
5290 break;
5291
5292 /* This operation is used for greedy *.
5293 Compare the beginning of the repeat with what in the
5294 pattern follows its end. If we can establish that there
5295 is nothing that they would both match, i.e., that we
5296 would have to backtrack because of (as in, e.g., `a*a')
5297 then we can use a non-backtracking loop based on
5298 on_failure_keep_string_jump instead of on_failure_jump. */
5299 case on_failure_jump_smart:
5300 IMMEDIATE_QUIT_CHECK;
5301 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5302 DEBUG_PRINT3 ("EXECUTING on_failure_jump_smart %d (to %p).\n",
5303 mcnt, p + mcnt);
5304 {
5305 re_char *p1 = p; /* Next operation. */
5306 /* Here, we discard `const', making re_match non-reentrant. */
5307 unsigned char *p2 = (unsigned char*) p + mcnt; /* Jump dest. */
5308 unsigned char *p3 = (unsigned char*) p - 3; /* opcode location. */
5309
5310 p -= 3; /* Reset so that we will re-execute the
5311 instruction once it's been changed. */
5312
5313 EXTRACT_NUMBER (mcnt, p2 - 2);
5314
5315 /* Ensure this is a indeed the trivial kind of loop
5316 we are expecting. */
5317 assert (skip_one_char (p1) == p2 - 3);
5318 assert ((re_opcode_t) p2[-3] == jump && p2 + mcnt == p);
5319 DEBUG_STATEMENT (debug += 2);
5320 if (mutually_exclusive_p (bufp, p1, p2))
5321 {
5322 /* Use a fast `on_failure_keep_string_jump' loop. */
5323 DEBUG_PRINT1 (" smart exclusive => fast loop.\n");
5324 *p3 = (unsigned char) on_failure_keep_string_jump;
5325 STORE_NUMBER (p2 - 2, mcnt + 3);
5326 }
5327 else
5328 {
5329 /* Default to a safe `on_failure_jump' loop. */
5330 DEBUG_PRINT1 (" smart default => slow loop.\n");
5331 *p3 = (unsigned char) on_failure_jump;
5332 }
5333 DEBUG_STATEMENT (debug -= 2);
5334 }
5335 break;
5336
5337 /* Unconditionally jump (without popping any failure points). */
5338 case jump:
5339 unconditional_jump:
5340 IMMEDIATE_QUIT_CHECK;
5341 EXTRACT_NUMBER_AND_INCR (mcnt, p); /* Get the amount to jump. */
5342 DEBUG_PRINT2 ("EXECUTING jump %d ", mcnt);
5343 p += mcnt; /* Do the jump. */
5344 DEBUG_PRINT2 ("(to %p).\n", p);
5345 break;
5346
5347
5348 /* Have to succeed matching what follows at least n times.
5349 After that, handle like `on_failure_jump'. */
5350 case succeed_n:
5351 /* Signedness doesn't matter since we only compare MCNT to 0. */
5352 EXTRACT_NUMBER (mcnt, p + 2);
5353 DEBUG_PRINT2 ("EXECUTING succeed_n %d.\n", mcnt);
5354
5355 /* Originally, mcnt is how many times we HAVE to succeed. */
5356 if (mcnt != 0)
5357 {
5358 /* Here, we discard `const', making re_match non-reentrant. */
5359 unsigned char *p2 = (unsigned char*) p + 2; /* counter loc. */
5360 mcnt--;
5361 p += 4;
5362 PUSH_NUMBER (p2, mcnt);
5363 }
5364 else
5365 /* The two bytes encoding mcnt == 0 are two no_op opcodes. */
5366 goto on_failure;
5367 break;
5368
5369 case jump_n:
5370 /* Signedness doesn't matter since we only compare MCNT to 0. */
5371 EXTRACT_NUMBER (mcnt, p + 2);
5372 DEBUG_PRINT2 ("EXECUTING jump_n %d.\n", mcnt);
5373
5374 /* Originally, this is how many times we CAN jump. */
5375 if (mcnt != 0)
5376 {
5377 /* Here, we discard `const', making re_match non-reentrant. */
5378 unsigned char *p2 = (unsigned char*) p + 2; /* counter loc. */
5379 mcnt--;
5380 PUSH_NUMBER (p2, mcnt);
5381 goto unconditional_jump;
5382 }
5383 /* If don't have to jump any more, skip over the rest of command. */
5384 else
5385 p += 4;
5386 break;
5387
5388 case set_number_at:
5389 {
5390 unsigned char *p2; /* Location of the counter. */
5391 DEBUG_PRINT1 ("EXECUTING set_number_at.\n");
5392
5393 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5394 /* Here, we discard `const', making re_match non-reentrant. */
5395 p2 = (unsigned char*) p + mcnt;
5396 /* Signedness doesn't matter since we only copy MCNT's bits . */
5397 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5398 DEBUG_PRINT3 (" Setting %p to %d.\n", p2, mcnt);
5399 PUSH_NUMBER (p2, mcnt);
5400 break;
5401 }
5402
5403 case wordbound:
5404 case notwordbound:
5405 not = (re_opcode_t) *(p - 1) == notwordbound;
5406 DEBUG_PRINT2 ("EXECUTING %swordbound.\n", not?"not":"");
5407
5408 /* We SUCCEED (or FAIL) in one of the following cases: */
5409
5410 /* Case 1: D is at the beginning or the end of string. */
5411 if (AT_STRINGS_BEG (d) || AT_STRINGS_END (d))
5412 not = !not;
5413 else
5414 {
5415 /* C1 is the character before D, S1 is the syntax of C1, C2
5416 is the character at D, and S2 is the syntax of C2. */
5417 re_wchar_t c1, c2;
5418 int s1, s2;
5419 #ifdef emacs
5420 int offset = PTR_TO_OFFSET (d - 1);
5421 int charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5422 UPDATE_SYNTAX_TABLE (charpos);
5423 #endif
5424 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5425 s1 = SYNTAX (c1);
5426 #ifdef emacs
5427 UPDATE_SYNTAX_TABLE_FORWARD (charpos + 1);
5428 #endif
5429 PREFETCH_NOLIMIT ();
5430 c2 = RE_STRING_CHAR (d, dend - d);
5431 s2 = SYNTAX (c2);
5432
5433 if (/* Case 2: Only one of S1 and S2 is Sword. */
5434 ((s1 == Sword) != (s2 == Sword))
5435 /* Case 3: Both of S1 and S2 are Sword, and macro
5436 WORD_BOUNDARY_P (C1, C2) returns nonzero. */
5437 || ((s1 == Sword) && WORD_BOUNDARY_P (c1, c2)))
5438 not = !not;
5439 }
5440 if (not)
5441 break;
5442 else
5443 goto fail;
5444
5445 case wordbeg:
5446 DEBUG_PRINT1 ("EXECUTING wordbeg.\n");
5447
5448 /* We FAIL in one of the following cases: */
5449
5450 /* Case 1: D is at the end of string. */
5451 if (AT_STRINGS_END (d))
5452 goto fail;
5453 else
5454 {
5455 /* C1 is the character before D, S1 is the syntax of C1, C2
5456 is the character at D, and S2 is the syntax of C2. */
5457 re_wchar_t c1, c2;
5458 int s1, s2;
5459 #ifdef emacs
5460 int offset = PTR_TO_OFFSET (d);
5461 int charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5462 UPDATE_SYNTAX_TABLE (charpos);
5463 #endif
5464 PREFETCH ();
5465 c2 = RE_STRING_CHAR (d, dend - d);
5466 s2 = SYNTAX (c2);
5467
5468 /* Case 2: S2 is not Sword. */
5469 if (s2 != Sword)
5470 goto fail;
5471
5472 /* Case 3: D is not at the beginning of string ... */
5473 if (!AT_STRINGS_BEG (d))
5474 {
5475 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5476 #ifdef emacs
5477 UPDATE_SYNTAX_TABLE_BACKWARD (charpos - 1);
5478 #endif
5479 s1 = SYNTAX (c1);
5480
5481 /* ... and S1 is Sword, and WORD_BOUNDARY_P (C1, C2)
5482 returns 0. */
5483 if ((s1 == Sword) && !WORD_BOUNDARY_P (c1, c2))
5484 goto fail;
5485 }
5486 }
5487 break;
5488
5489 case wordend:
5490 DEBUG_PRINT1 ("EXECUTING wordend.\n");
5491
5492 /* We FAIL in one of the following cases: */
5493
5494 /* Case 1: D is at the beginning of string. */
5495 if (AT_STRINGS_BEG (d))
5496 goto fail;
5497 else
5498 {
5499 /* C1 is the character before D, S1 is the syntax of C1, C2
5500 is the character at D, and S2 is the syntax of C2. */
5501 re_wchar_t c1, c2;
5502 int s1, s2;
5503 #ifdef emacs
5504 int offset = PTR_TO_OFFSET (d) - 1;
5505 int charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5506 UPDATE_SYNTAX_TABLE (charpos);
5507 #endif
5508 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5509 s1 = SYNTAX (c1);
5510
5511 /* Case 2: S1 is not Sword. */
5512 if (s1 != Sword)
5513 goto fail;
5514
5515 /* Case 3: D is not at the end of string ... */
5516 if (!AT_STRINGS_END (d))
5517 {
5518 PREFETCH_NOLIMIT ();
5519 c2 = RE_STRING_CHAR (d, dend - d);
5520 #ifdef emacs
5521 UPDATE_SYNTAX_TABLE_FORWARD (charpos);
5522 #endif
5523 s2 = SYNTAX (c2);
5524
5525 /* ... and S2 is Sword, and WORD_BOUNDARY_P (C1, C2)
5526 returns 0. */
5527 if ((s2 == Sword) && !WORD_BOUNDARY_P (c1, c2))
5528 goto fail;
5529 }
5530 }
5531 break;
5532
5533 case syntaxspec:
5534 case notsyntaxspec:
5535 not = (re_opcode_t) *(p - 1) == notsyntaxspec;
5536 mcnt = *p++;
5537 DEBUG_PRINT3 ("EXECUTING %ssyntaxspec %d.\n", not?"not":"", mcnt);
5538 PREFETCH ();
5539 #ifdef emacs
5540 {
5541 int offset = PTR_TO_OFFSET (d);
5542 int pos1 = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5543 UPDATE_SYNTAX_TABLE (pos1);
5544 }
5545 #endif
5546 {
5547 int len;
5548 re_wchar_t c;
5549
5550 c = RE_STRING_CHAR_AND_LENGTH (d, dend - d, len);
5551
5552 if ((SYNTAX (c) != (enum syntaxcode) mcnt) ^ not)
5553 goto fail;
5554 d += len;
5555 }
5556 break;
5557
5558 #ifdef emacs
5559 case before_dot:
5560 DEBUG_PRINT1 ("EXECUTING before_dot.\n");
5561 if (PTR_BYTE_POS (d) >= PT_BYTE)
5562 goto fail;
5563 break;
5564
5565 case at_dot:
5566 DEBUG_PRINT1 ("EXECUTING at_dot.\n");
5567 if (PTR_BYTE_POS (d) != PT_BYTE)
5568 goto fail;
5569 break;
5570
5571 case after_dot:
5572 DEBUG_PRINT1 ("EXECUTING after_dot.\n");
5573 if (PTR_BYTE_POS (d) <= PT_BYTE)
5574 goto fail;
5575 break;
5576
5577 case categoryspec:
5578 case notcategoryspec:
5579 not = (re_opcode_t) *(p - 1) == notcategoryspec;
5580 mcnt = *p++;
5581 DEBUG_PRINT3 ("EXECUTING %scategoryspec %d.\n", not?"not":"", mcnt);
5582 PREFETCH ();
5583 {
5584 int len;
5585 re_wchar_t c;
5586
5587 c = RE_STRING_CHAR_AND_LENGTH (d, dend - d, len);
5588
5589 if ((!CHAR_HAS_CATEGORY (c, mcnt)) ^ not)
5590 goto fail;
5591 d += len;
5592 }
5593 break;
5594
5595 #endif /* emacs */
5596
5597 default:
5598 abort ();
5599 }
5600 continue; /* Successfully executed one pattern command; keep going. */
5601
5602
5603 /* We goto here if a matching operation fails. */
5604 fail:
5605 IMMEDIATE_QUIT_CHECK;
5606 if (!FAIL_STACK_EMPTY ())
5607 {
5608 re_char *str, *pat;
5609 /* A restart point is known. Restore to that state. */
5610 DEBUG_PRINT1 ("\nFAIL:\n");
5611 POP_FAILURE_POINT (str, pat);
5612 switch (SWITCH_ENUM_CAST ((re_opcode_t) *pat++))
5613 {
5614 case on_failure_keep_string_jump:
5615 assert (str == NULL);
5616 goto continue_failure_jump;
5617
5618 case on_failure_jump_nastyloop:
5619 assert ((re_opcode_t)pat[-2] == no_op);
5620 PUSH_FAILURE_POINT (pat - 2, str);
5621 /* Fallthrough */
5622
5623 case on_failure_jump_loop:
5624 case on_failure_jump:
5625 case succeed_n:
5626 d = str;
5627 continue_failure_jump:
5628 EXTRACT_NUMBER_AND_INCR (mcnt, pat);
5629 p = pat + mcnt;
5630 break;
5631
5632 case no_op:
5633 /* A special frame used for nastyloops. */
5634 goto fail;
5635
5636 default:
5637 abort();
5638 }
5639
5640 assert (p >= bufp->buffer && p <= pend);
5641
5642 if (d >= string1 && d <= end1)
5643 dend = end_match_1;
5644 }
5645 else
5646 break; /* Matching at this starting point really fails. */
5647 } /* for (;;) */
5648
5649 if (best_regs_set)
5650 goto restore_best_regs;
5651
5652 FREE_VARIABLES ();
5653
5654 return -1; /* Failure to match. */
5655 } /* re_match_2 */
5656 \f
5657 /* Subroutine definitions for re_match_2. */
5658
5659 /* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
5660 bytes; nonzero otherwise. */
5661
5662 static int
5663 bcmp_translate (s1, s2, len, translate, multibyte)
5664 re_char *s1, *s2;
5665 register int len;
5666 RE_TRANSLATE_TYPE translate;
5667 const int multibyte;
5668 {
5669 register re_char *p1 = s1, *p2 = s2;
5670 re_char *p1_end = s1 + len;
5671 re_char *p2_end = s2 + len;
5672
5673 /* FIXME: Checking both p1 and p2 presumes that the two strings might have
5674 different lengths, but relying on a single `len' would break this. -sm */
5675 while (p1 < p1_end && p2 < p2_end)
5676 {
5677 int p1_charlen, p2_charlen;
5678 re_wchar_t p1_ch, p2_ch;
5679
5680 p1_ch = RE_STRING_CHAR_AND_LENGTH (p1, p1_end - p1, p1_charlen);
5681 p2_ch = RE_STRING_CHAR_AND_LENGTH (p2, p2_end - p2, p2_charlen);
5682
5683 if (RE_TRANSLATE (translate, p1_ch)
5684 != RE_TRANSLATE (translate, p2_ch))
5685 return 1;
5686
5687 p1 += p1_charlen, p2 += p2_charlen;
5688 }
5689
5690 if (p1 != p1_end || p2 != p2_end)
5691 return 1;
5692
5693 return 0;
5694 }
5695 \f
5696 /* Entry points for GNU code. */
5697
5698 /* re_compile_pattern is the GNU regular expression compiler: it
5699 compiles PATTERN (of length SIZE) and puts the result in BUFP.
5700 Returns 0 if the pattern was valid, otherwise an error string.
5701
5702 Assumes the `allocated' (and perhaps `buffer') and `translate' fields
5703 are set in BUFP on entry.
5704
5705 We call regex_compile to do the actual compilation. */
5706
5707 const char *
5708 re_compile_pattern (pattern, length, bufp)
5709 const char *pattern;
5710 size_t length;
5711 struct re_pattern_buffer *bufp;
5712 {
5713 reg_errcode_t ret;
5714
5715 /* GNU code is written to assume at least RE_NREGS registers will be set
5716 (and at least one extra will be -1). */
5717 bufp->regs_allocated = REGS_UNALLOCATED;
5718
5719 /* And GNU code determines whether or not to get register information
5720 by passing null for the REGS argument to re_match, etc., not by
5721 setting no_sub. */
5722 bufp->no_sub = 0;
5723
5724 ret = regex_compile ((re_char*) pattern, length, re_syntax_options, bufp);
5725
5726 if (!ret)
5727 return NULL;
5728 return gettext (re_error_msgid[(int) ret]);
5729 }
5730 WEAK_ALIAS (__re_compile_pattern, re_compile_pattern)
5731 \f
5732 /* Entry points compatible with 4.2 BSD regex library. We don't define
5733 them unless specifically requested. */
5734
5735 #if defined _REGEX_RE_COMP || defined _LIBC
5736
5737 /* BSD has one and only one pattern buffer. */
5738 static struct re_pattern_buffer re_comp_buf;
5739
5740 char *
5741 # ifdef _LIBC
5742 /* Make these definitions weak in libc, so POSIX programs can redefine
5743 these names if they don't use our functions, and still use
5744 regcomp/regexec below without link errors. */
5745 weak_function
5746 # endif
5747 re_comp (s)
5748 const char *s;
5749 {
5750 reg_errcode_t ret;
5751
5752 if (!s)
5753 {
5754 if (!re_comp_buf.buffer)
5755 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
5756 return (char *) gettext ("No previous regular expression");
5757 return 0;
5758 }
5759
5760 if (!re_comp_buf.buffer)
5761 {
5762 re_comp_buf.buffer = (unsigned char *) malloc (200);
5763 if (re_comp_buf.buffer == NULL)
5764 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
5765 return (char *) gettext (re_error_msgid[(int) REG_ESPACE]);
5766 re_comp_buf.allocated = 200;
5767
5768 re_comp_buf.fastmap = (char *) malloc (1 << BYTEWIDTH);
5769 if (re_comp_buf.fastmap == NULL)
5770 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
5771 return (char *) gettext (re_error_msgid[(int) REG_ESPACE]);
5772 }
5773
5774 /* Since `re_exec' always passes NULL for the `regs' argument, we
5775 don't need to initialize the pattern buffer fields which affect it. */
5776
5777 ret = regex_compile (s, strlen (s), re_syntax_options, &re_comp_buf);
5778
5779 if (!ret)
5780 return NULL;
5781
5782 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
5783 return (char *) gettext (re_error_msgid[(int) ret]);
5784 }
5785
5786
5787 int
5788 # ifdef _LIBC
5789 weak_function
5790 # endif
5791 re_exec (s)
5792 const char *s;
5793 {
5794 const int len = strlen (s);
5795 return
5796 0 <= re_search (&re_comp_buf, s, len, 0, len, (struct re_registers *) 0);
5797 }
5798 #endif /* _REGEX_RE_COMP */
5799 \f
5800 /* POSIX.2 functions. Don't define these for Emacs. */
5801
5802 #ifndef emacs
5803
5804 /* regcomp takes a regular expression as a string and compiles it.
5805
5806 PREG is a regex_t *. We do not expect any fields to be initialized,
5807 since POSIX says we shouldn't. Thus, we set
5808
5809 `buffer' to the compiled pattern;
5810 `used' to the length of the compiled pattern;
5811 `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
5812 REG_EXTENDED bit in CFLAGS is set; otherwise, to
5813 RE_SYNTAX_POSIX_BASIC;
5814 `fastmap' to an allocated space for the fastmap;
5815 `fastmap_accurate' to zero;
5816 `re_nsub' to the number of subexpressions in PATTERN.
5817
5818 PATTERN is the address of the pattern string.
5819
5820 CFLAGS is a series of bits which affect compilation.
5821
5822 If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
5823 use POSIX basic syntax.
5824
5825 If REG_NEWLINE is set, then . and [^...] don't match newline.
5826 Also, regexec will try a match beginning after every newline.
5827
5828 If REG_ICASE is set, then we considers upper- and lowercase
5829 versions of letters to be equivalent when matching.
5830
5831 If REG_NOSUB is set, then when PREG is passed to regexec, that
5832 routine will report only success or failure, and nothing about the
5833 registers.
5834
5835 It returns 0 if it succeeds, nonzero if it doesn't. (See regex.h for
5836 the return codes and their meanings.) */
5837
5838 int
5839 regcomp (preg, pattern, cflags)
5840 regex_t *preg;
5841 const char *pattern;
5842 int cflags;
5843 {
5844 reg_errcode_t ret;
5845 reg_syntax_t syntax
5846 = (cflags & REG_EXTENDED) ?
5847 RE_SYNTAX_POSIX_EXTENDED : RE_SYNTAX_POSIX_BASIC;
5848
5849 /* regex_compile will allocate the space for the compiled pattern. */
5850 preg->buffer = 0;
5851 preg->allocated = 0;
5852 preg->used = 0;
5853
5854 /* Try to allocate space for the fastmap. */
5855 preg->fastmap = (char *) malloc (1 << BYTEWIDTH);
5856
5857 if (cflags & REG_ICASE)
5858 {
5859 unsigned i;
5860
5861 preg->translate
5862 = (RE_TRANSLATE_TYPE) malloc (CHAR_SET_SIZE
5863 * sizeof (*(RE_TRANSLATE_TYPE)0));
5864 if (preg->translate == NULL)
5865 return (int) REG_ESPACE;
5866
5867 /* Map uppercase characters to corresponding lowercase ones. */
5868 for (i = 0; i < CHAR_SET_SIZE; i++)
5869 preg->translate[i] = ISUPPER (i) ? TOLOWER (i) : i;
5870 }
5871 else
5872 preg->translate = NULL;
5873
5874 /* If REG_NEWLINE is set, newlines are treated differently. */
5875 if (cflags & REG_NEWLINE)
5876 { /* REG_NEWLINE implies neither . nor [^...] match newline. */
5877 syntax &= ~RE_DOT_NEWLINE;
5878 syntax |= RE_HAT_LISTS_NOT_NEWLINE;
5879 }
5880 else
5881 syntax |= RE_NO_NEWLINE_ANCHOR;
5882
5883 preg->no_sub = !!(cflags & REG_NOSUB);
5884
5885 /* POSIX says a null character in the pattern terminates it, so we
5886 can use strlen here in compiling the pattern. */
5887 ret = regex_compile ((re_char*) pattern, strlen (pattern), syntax, preg);
5888
5889 /* POSIX doesn't distinguish between an unmatched open-group and an
5890 unmatched close-group: both are REG_EPAREN. */
5891 if (ret == REG_ERPAREN)
5892 ret = REG_EPAREN;
5893
5894 if (ret == REG_NOERROR && preg->fastmap)
5895 { /* Compute the fastmap now, since regexec cannot modify the pattern
5896 buffer. */
5897 re_compile_fastmap (preg);
5898 if (preg->can_be_null)
5899 { /* The fastmap can't be used anyway. */
5900 free (preg->fastmap);
5901 preg->fastmap = NULL;
5902 }
5903 }
5904 return (int) ret;
5905 }
5906 WEAK_ALIAS (__regcomp, regcomp)
5907
5908
5909 /* regexec searches for a given pattern, specified by PREG, in the
5910 string STRING.
5911
5912 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
5913 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
5914 least NMATCH elements, and we set them to the offsets of the
5915 corresponding matched substrings.
5916
5917 EFLAGS specifies `execution flags' which affect matching: if
5918 REG_NOTBOL is set, then ^ does not match at the beginning of the
5919 string; if REG_NOTEOL is set, then $ does not match at the end.
5920
5921 We return 0 if we find a match and REG_NOMATCH if not. */
5922
5923 int
5924 regexec (preg, string, nmatch, pmatch, eflags)
5925 const regex_t *preg;
5926 const char *string;
5927 size_t nmatch;
5928 regmatch_t pmatch[];
5929 int eflags;
5930 {
5931 int ret;
5932 struct re_registers regs;
5933 regex_t private_preg;
5934 int len = strlen (string);
5935 boolean want_reg_info = !preg->no_sub && nmatch > 0 && pmatch;
5936
5937 private_preg = *preg;
5938
5939 private_preg.not_bol = !!(eflags & REG_NOTBOL);
5940 private_preg.not_eol = !!(eflags & REG_NOTEOL);
5941
5942 /* The user has told us exactly how many registers to return
5943 information about, via `nmatch'. We have to pass that on to the
5944 matching routines. */
5945 private_preg.regs_allocated = REGS_FIXED;
5946
5947 if (want_reg_info)
5948 {
5949 regs.num_regs = nmatch;
5950 regs.start = TALLOC (nmatch * 2, regoff_t);
5951 if (regs.start == NULL)
5952 return (int) REG_NOMATCH;
5953 regs.end = regs.start + nmatch;
5954 }
5955
5956 /* Instead of using not_eol to implement REG_NOTEOL, we could simply
5957 pass (&private_preg, string, len + 1, 0, len, ...) pretending the string
5958 was a little bit longer but still only matching the real part.
5959 This works because the `endline' will check for a '\n' and will find a
5960 '\0', correctly deciding that this is not the end of a line.
5961 But it doesn't work out so nicely for REG_NOTBOL, since we don't have
5962 a convenient '\0' there. For all we know, the string could be preceded
5963 by '\n' which would throw things off. */
5964
5965 /* Perform the searching operation. */
5966 ret = re_search (&private_preg, string, len,
5967 /* start: */ 0, /* range: */ len,
5968 want_reg_info ? &regs : (struct re_registers *) 0);
5969
5970 /* Copy the register information to the POSIX structure. */
5971 if (want_reg_info)
5972 {
5973 if (ret >= 0)
5974 {
5975 unsigned r;
5976
5977 for (r = 0; r < nmatch; r++)
5978 {
5979 pmatch[r].rm_so = regs.start[r];
5980 pmatch[r].rm_eo = regs.end[r];
5981 }
5982 }
5983
5984 /* If we needed the temporary register info, free the space now. */
5985 free (regs.start);
5986 }
5987
5988 /* We want zero return to mean success, unlike `re_search'. */
5989 return ret >= 0 ? (int) REG_NOERROR : (int) REG_NOMATCH;
5990 }
5991 WEAK_ALIAS (__regexec, regexec)
5992
5993
5994 /* Returns a message corresponding to an error code, ERRCODE, returned
5995 from either regcomp or regexec. We don't use PREG here. */
5996
5997 size_t
5998 regerror (errcode, preg, errbuf, errbuf_size)
5999 int errcode;
6000 const regex_t *preg;
6001 char *errbuf;
6002 size_t errbuf_size;
6003 {
6004 const char *msg;
6005 size_t msg_size;
6006
6007 if (errcode < 0
6008 || errcode >= (sizeof (re_error_msgid) / sizeof (re_error_msgid[0])))
6009 /* Only error codes returned by the rest of the code should be passed
6010 to this routine. If we are given anything else, or if other regex
6011 code generates an invalid error code, then the program has a bug.
6012 Dump core so we can fix it. */
6013 abort ();
6014
6015 msg = gettext (re_error_msgid[errcode]);
6016
6017 msg_size = strlen (msg) + 1; /* Includes the null. */
6018
6019 if (errbuf_size != 0)
6020 {
6021 if (msg_size > errbuf_size)
6022 {
6023 strncpy (errbuf, msg, errbuf_size - 1);
6024 errbuf[errbuf_size - 1] = 0;
6025 }
6026 else
6027 strcpy (errbuf, msg);
6028 }
6029
6030 return msg_size;
6031 }
6032 WEAK_ALIAS (__regerror, regerror)
6033
6034
6035 /* Free dynamically allocated space used by PREG. */
6036
6037 void
6038 regfree (preg)
6039 regex_t *preg;
6040 {
6041 if (preg->buffer != NULL)
6042 free (preg->buffer);
6043 preg->buffer = NULL;
6044
6045 preg->allocated = 0;
6046 preg->used = 0;
6047
6048 if (preg->fastmap != NULL)
6049 free (preg->fastmap);
6050 preg->fastmap = NULL;
6051 preg->fastmap_accurate = 0;
6052
6053 if (preg->translate != NULL)
6054 free (preg->translate);
6055 preg->translate = NULL;
6056 }
6057 WEAK_ALIAS (__regfree, regfree)
6058
6059 #endif /* not emacs */
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