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