]> code.delx.au - gnu-emacs/blob - src/regex.c
(re_match_2_internal) [WINDOWSNT & emacs]: Insert QUIT at various places.
[gnu-emacs] / src / regex.c
1 /* Extended regular expression matching and search library, version
2 0.12. (Implements POSIX draft P10003.2/D11.2, except for
3 internationalization features.)
4
5 Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998 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 /* AIX requires this to be the first thing in the file. */
23 #if defined (_AIX) && !defined (REGEX_MALLOC)
24 #pragma alloca
25 #endif
26
27 #undef _GNU_SOURCE
28 #define _GNU_SOURCE
29
30 #ifdef emacs
31 /* Converts the pointer to the char to BEG-based offset from the start. */
32 #define PTR_TO_OFFSET(d) \
33 POS_AS_IN_BUFFER (MATCHING_IN_FIRST_STRING \
34 ? (d) - string1 : (d) - (string2 - size1))
35 #define POS_AS_IN_BUFFER(p) ((p) + (NILP (re_match_object) || BUFFERP (re_match_object)))
36 #else
37 #define PTR_TO_OFFSET(d) 0
38 #endif
39
40 #ifdef HAVE_CONFIG_H
41 #include <config.h>
42 #endif
43
44 /* We need this for `regex.h', and perhaps for the Emacs include files. */
45 #include <sys/types.h>
46
47 /* This is for other GNU distributions with internationalized messages. */
48 #if HAVE_LIBINTL_H || defined (_LIBC)
49 # include <libintl.h>
50 #else
51 # define gettext(msgid) (msgid)
52 #endif
53
54 #ifndef gettext_noop
55 /* This define is so xgettext can find the internationalizable
56 strings. */
57 #define gettext_noop(String) String
58 #endif
59
60 /* The `emacs' switch turns on certain matching commands
61 that make sense only in Emacs. */
62 #ifdef emacs
63
64 #include "lisp.h"
65 #include "buffer.h"
66
67 /* Make syntax table lookup grant data in gl_state. */
68 #define SYNTAX_ENTRY_VIA_PROPERTY
69
70 #include "syntax.h"
71 #include "charset.h"
72 #include "category.h"
73
74 #define malloc xmalloc
75 #define realloc xrealloc
76 #define free xfree
77
78 #else /* not emacs */
79
80 /* If we are not linking with Emacs proper,
81 we can't use the relocating allocator
82 even if config.h says that we can. */
83 #undef REL_ALLOC
84
85 #if defined (STDC_HEADERS) || defined (_LIBC)
86 #include <stdlib.h>
87 #else
88 char *malloc ();
89 char *realloc ();
90 #endif
91
92 /* When used in Emacs's lib-src, we need to get bzero and bcopy somehow.
93 If nothing else has been done, use the method below. */
94 #ifdef INHIBIT_STRING_HEADER
95 #if !(defined (HAVE_BZERO) && defined (HAVE_BCOPY))
96 #if !defined (bzero) && !defined (bcopy)
97 #undef INHIBIT_STRING_HEADER
98 #endif
99 #endif
100 #endif
101
102 /* This is the normal way of making sure we have a bcopy and a bzero.
103 This is used in most programs--a few other programs avoid this
104 by defining INHIBIT_STRING_HEADER. */
105 #ifndef INHIBIT_STRING_HEADER
106 #if defined (HAVE_STRING_H) || defined (STDC_HEADERS) || defined (_LIBC)
107 #include <string.h>
108 #ifndef bcmp
109 #define bcmp(s1, s2, n) memcmp ((s1), (s2), (n))
110 #endif
111 #ifndef bcopy
112 #define bcopy(s, d, n) memcpy ((d), (s), (n))
113 #endif
114 #ifndef bzero
115 #define bzero(s, n) memset ((s), 0, (n))
116 #endif
117 #else
118 #include <strings.h>
119 #endif
120 #endif
121
122 /* Define the syntax stuff for \<, \>, etc. */
123
124 /* This must be nonzero for the wordchar and notwordchar pattern
125 commands in re_match_2. */
126 #ifndef Sword
127 #define Sword 1
128 #endif
129
130 #ifdef SWITCH_ENUM_BUG
131 #define SWITCH_ENUM_CAST(x) ((int)(x))
132 #else
133 #define SWITCH_ENUM_CAST(x) (x)
134 #endif
135
136 #ifdef SYNTAX_TABLE
137
138 extern char *re_syntax_table;
139
140 #else /* not SYNTAX_TABLE */
141
142 /* How many characters in the character set. */
143 #define CHAR_SET_SIZE 256
144
145 static char re_syntax_table[CHAR_SET_SIZE];
146
147 static void
148 init_syntax_once ()
149 {
150 register int c;
151 static int done = 0;
152
153 if (done)
154 return;
155
156 bzero (re_syntax_table, sizeof re_syntax_table);
157
158 for (c = 'a'; c <= 'z'; c++)
159 re_syntax_table[c] = Sword;
160
161 for (c = 'A'; c <= 'Z'; c++)
162 re_syntax_table[c] = Sword;
163
164 for (c = '0'; c <= '9'; c++)
165 re_syntax_table[c] = Sword;
166
167 re_syntax_table['_'] = Sword;
168
169 done = 1;
170 }
171
172 #endif /* not SYNTAX_TABLE */
173
174 #define SYNTAX(c) re_syntax_table[c]
175
176 /* Dummy macros for non-Emacs environments. */
177 #define BASE_LEADING_CODE_P(c) (0)
178 #define WORD_BOUNDARY_P(c1, c2) (0)
179 #define CHAR_HEAD_P(p) (1)
180 #define SINGLE_BYTE_CHAR_P(c) (1)
181 #define SAME_CHARSET_P(c1, c2) (1)
182 #define MULTIBYTE_FORM_LENGTH(p, s) (1)
183 #define STRING_CHAR(p, s) (*(p))
184 #define STRING_CHAR_AND_LENGTH(p, s, actual_len) ((actual_len) = 1, *(p))
185 #define GET_CHAR_AFTER_2(c, p, str1, end1, str2, end2) \
186 (c = ((p) == (end1) ? *(str2) : *(p)))
187 #define GET_CHAR_BEFORE_2(c, p, str1, end1, str2, end2) \
188 (c = ((p) == (str2) ? *((end1) - 1) : *((p) - 1)))
189 #endif /* not emacs */
190 \f
191 /* Get the interface, including the syntax bits. */
192 #include "regex.h"
193
194 /* isalpha etc. are used for the character classes. */
195 #include <ctype.h>
196
197 /* Jim Meyering writes:
198
199 "... Some ctype macros are valid only for character codes that
200 isascii says are ASCII (SGI's IRIX-4.0.5 is one such system --when
201 using /bin/cc or gcc but without giving an ansi option). So, all
202 ctype uses should be through macros like ISPRINT... If
203 STDC_HEADERS is defined, then autoconf has verified that the ctype
204 macros don't need to be guarded with references to isascii. ...
205 Defining isascii to 1 should let any compiler worth its salt
206 eliminate the && through constant folding." */
207
208 #if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII))
209 #define ISASCII(c) 1
210 #else
211 #define ISASCII(c) isascii(c)
212 #endif
213
214 #ifdef isblank
215 #define ISBLANK(c) (ISASCII (c) && isblank (c))
216 #else
217 #define ISBLANK(c) ((c) == ' ' || (c) == '\t')
218 #endif
219 #ifdef isgraph
220 #define ISGRAPH(c) (ISASCII (c) && isgraph (c))
221 #else
222 #define ISGRAPH(c) (ISASCII (c) && isprint (c) && !isspace (c))
223 #endif
224
225 #define ISPRINT(c) (ISASCII (c) && isprint (c))
226 #define ISDIGIT(c) (ISASCII (c) && isdigit (c))
227 #define ISALNUM(c) (ISASCII (c) && isalnum (c))
228 #define ISALPHA(c) (ISASCII (c) && isalpha (c))
229 #define ISCNTRL(c) (ISASCII (c) && iscntrl (c))
230 #define ISLOWER(c) (ISASCII (c) && islower (c))
231 #define ISPUNCT(c) (ISASCII (c) && ispunct (c))
232 #define ISSPACE(c) (ISASCII (c) && isspace (c))
233 #define ISUPPER(c) (ISASCII (c) && isupper (c))
234 #define ISXDIGIT(c) (ISASCII (c) && isxdigit (c))
235
236 #ifndef NULL
237 #define NULL (void *)0
238 #endif
239
240 /* We remove any previous definition of `SIGN_EXTEND_CHAR',
241 since ours (we hope) works properly with all combinations of
242 machines, compilers, `char' and `unsigned char' argument types.
243 (Per Bothner suggested the basic approach.) */
244 #undef SIGN_EXTEND_CHAR
245 #if __STDC__
246 #define SIGN_EXTEND_CHAR(c) ((signed char) (c))
247 #else /* not __STDC__ */
248 /* As in Harbison and Steele. */
249 #define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128)
250 #endif
251 \f
252 /* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we
253 use `alloca' instead of `malloc'. This is because using malloc in
254 re_search* or re_match* could cause memory leaks when C-g is used in
255 Emacs; also, malloc is slower and causes storage fragmentation. On
256 the other hand, malloc is more portable, and easier to debug.
257
258 Because we sometimes use alloca, some routines have to be macros,
259 not functions -- `alloca'-allocated space disappears at the end of the
260 function it is called in. */
261
262 #ifdef REGEX_MALLOC
263
264 #define REGEX_ALLOCATE malloc
265 #define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
266 #define REGEX_FREE free
267
268 #else /* not REGEX_MALLOC */
269
270 /* Emacs already defines alloca, sometimes. */
271 #ifndef alloca
272
273 /* Make alloca work the best possible way. */
274 #ifdef __GNUC__
275 #define alloca __builtin_alloca
276 #else /* not __GNUC__ */
277 #if HAVE_ALLOCA_H
278 #include <alloca.h>
279 #else /* not __GNUC__ or HAVE_ALLOCA_H */
280 #if 0 /* It is a bad idea to declare alloca. We always cast the result. */
281 #ifndef _AIX /* Already did AIX, up at the top. */
282 char *alloca ();
283 #endif /* not _AIX */
284 #endif
285 #endif /* not HAVE_ALLOCA_H */
286 #endif /* not __GNUC__ */
287
288 #endif /* not alloca */
289
290 #define REGEX_ALLOCATE alloca
291
292 /* Assumes a `char *destination' variable. */
293 #define REGEX_REALLOCATE(source, osize, nsize) \
294 (destination = (char *) alloca (nsize), \
295 bcopy (source, destination, osize), \
296 destination)
297
298 /* No need to do anything to free, after alloca. */
299 #define REGEX_FREE(arg) ((void)0) /* Do nothing! But inhibit gcc warning. */
300
301 #endif /* not REGEX_MALLOC */
302
303 /* Define how to allocate the failure stack. */
304
305 #if defined (REL_ALLOC) && defined (REGEX_MALLOC)
306
307 #define REGEX_ALLOCATE_STACK(size) \
308 r_alloc (&failure_stack_ptr, (size))
309 #define REGEX_REALLOCATE_STACK(source, osize, nsize) \
310 r_re_alloc (&failure_stack_ptr, (nsize))
311 #define REGEX_FREE_STACK(ptr) \
312 r_alloc_free (&failure_stack_ptr)
313
314 #else /* not using relocating allocator */
315
316 #ifdef REGEX_MALLOC
317
318 #define REGEX_ALLOCATE_STACK malloc
319 #define REGEX_REALLOCATE_STACK(source, osize, nsize) realloc (source, nsize)
320 #define REGEX_FREE_STACK free
321
322 #else /* not REGEX_MALLOC */
323
324 #define REGEX_ALLOCATE_STACK alloca
325
326 #define REGEX_REALLOCATE_STACK(source, osize, nsize) \
327 REGEX_REALLOCATE (source, osize, nsize)
328 /* No need to explicitly free anything. */
329 #define REGEX_FREE_STACK(arg)
330
331 #endif /* not REGEX_MALLOC */
332 #endif /* not using relocating allocator */
333
334
335 /* True if `size1' is non-NULL and PTR is pointing anywhere inside
336 `string1' or just past its end. This works if PTR is NULL, which is
337 a good thing. */
338 #define FIRST_STRING_P(ptr) \
339 (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
340
341 /* (Re)Allocate N items of type T using malloc, or fail. */
342 #define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
343 #define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
344 #define RETALLOC_IF(addr, n, t) \
345 if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
346 #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
347
348 #define BYTEWIDTH 8 /* In bits. */
349
350 #define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
351
352 #undef MAX
353 #undef MIN
354 #define MAX(a, b) ((a) > (b) ? (a) : (b))
355 #define MIN(a, b) ((a) < (b) ? (a) : (b))
356
357 typedef char boolean;
358 #define false 0
359 #define true 1
360
361 static int re_match_2_internal ();
362 \f
363 /* These are the command codes that appear in compiled regular
364 expressions. Some opcodes are followed by argument bytes. A
365 command code can specify any interpretation whatsoever for its
366 arguments. Zero bytes may appear in the compiled regular expression. */
367
368 typedef enum
369 {
370 no_op = 0,
371
372 /* Succeed right away--no more backtracking. */
373 succeed,
374
375 /* Followed by one byte giving n, then by n literal bytes. */
376 exactn,
377
378 /* Matches any (more or less) character. */
379 anychar,
380
381 /* Matches any one char belonging to specified set. First
382 following byte is number of bitmap bytes. Then come bytes
383 for a bitmap saying which chars are in. Bits in each byte
384 are ordered low-bit-first. A character is in the set if its
385 bit is 1. A character too large to have a bit in the map is
386 automatically not in the set. */
387 charset,
388
389 /* Same parameters as charset, but match any character that is
390 not one of those specified. */
391 charset_not,
392
393 /* Start remembering the text that is matched, for storing in a
394 register. Followed by one byte with the register number, in
395 the range 0 to one less than the pattern buffer's re_nsub
396 field. Then followed by one byte with the number of groups
397 inner to this one. (This last has to be part of the
398 start_memory only because we need it in the on_failure_jump
399 of re_match_2.) */
400 start_memory,
401
402 /* Stop remembering the text that is matched and store it in a
403 memory register. Followed by one byte with the register
404 number, in the range 0 to one less than `re_nsub' in the
405 pattern buffer, and one byte with the number of inner groups,
406 just like `start_memory'. (We need the number of inner
407 groups here because we don't have any easy way of finding the
408 corresponding start_memory when we're at a stop_memory.) */
409 stop_memory,
410
411 /* Match a duplicate of something remembered. Followed by one
412 byte containing the register number. */
413 duplicate,
414
415 /* Fail unless at beginning of line. */
416 begline,
417
418 /* Fail unless at end of line. */
419 endline,
420
421 /* Succeeds if at beginning of buffer (if emacs) or at beginning
422 of string to be matched (if not). */
423 begbuf,
424
425 /* Analogously, for end of buffer/string. */
426 endbuf,
427
428 /* Followed by two byte relative address to which to jump. */
429 jump,
430
431 /* Same as jump, but marks the end of an alternative. */
432 jump_past_alt,
433
434 /* Followed by two-byte relative address of place to resume at
435 in case of failure. */
436 on_failure_jump,
437
438 /* Like on_failure_jump, but pushes a placeholder instead of the
439 current string position when executed. */
440 on_failure_keep_string_jump,
441
442 /* Throw away latest failure point and then jump to following
443 two-byte relative address. */
444 pop_failure_jump,
445
446 /* Change to pop_failure_jump if know won't have to backtrack to
447 match; otherwise change to jump. This is used to jump
448 back to the beginning of a repeat. If what follows this jump
449 clearly won't match what the repeat does, such that we can be
450 sure that there is no use backtracking out of repetitions
451 already matched, then we change it to a pop_failure_jump.
452 Followed by two-byte address. */
453 maybe_pop_jump,
454
455 /* Jump to following two-byte address, and push a dummy failure
456 point. This failure point will be thrown away if an attempt
457 is made to use it for a failure. A `+' construct makes this
458 before the first repeat. Also used as an intermediary kind
459 of jump when compiling an alternative. */
460 dummy_failure_jump,
461
462 /* Push a dummy failure point and continue. Used at the end of
463 alternatives. */
464 push_dummy_failure,
465
466 /* Followed by two-byte relative address and two-byte number n.
467 After matching N times, jump to the address upon failure. */
468 succeed_n,
469
470 /* Followed by two-byte relative address, and two-byte number n.
471 Jump to the address N times, then fail. */
472 jump_n,
473
474 /* Set the following two-byte relative address to the
475 subsequent two-byte number. The address *includes* the two
476 bytes of number. */
477 set_number_at,
478
479 wordchar, /* Matches any word-constituent character. */
480 notwordchar, /* Matches any char that is not a word-constituent. */
481
482 wordbeg, /* Succeeds if at word beginning. */
483 wordend, /* Succeeds if at word end. */
484
485 wordbound, /* Succeeds if at a word boundary. */
486 notwordbound /* Succeeds if not at a word boundary. */
487
488 #ifdef emacs
489 ,before_dot, /* Succeeds if before point. */
490 at_dot, /* Succeeds if at point. */
491 after_dot, /* Succeeds if after point. */
492
493 /* Matches any character whose syntax is specified. Followed by
494 a byte which contains a syntax code, e.g., Sword. */
495 syntaxspec,
496
497 /* Matches any character whose syntax is not that specified. */
498 notsyntaxspec,
499
500 /* Matches any character whose category-set contains the specified
501 category. The operator is followed by a byte which contains a
502 category code (mnemonic ASCII character). */
503 categoryspec,
504
505 /* Matches any character whose category-set does not contain the
506 specified category. The operator is followed by a byte which
507 contains the category code (mnemonic ASCII character). */
508 notcategoryspec
509 #endif /* emacs */
510 } re_opcode_t;
511 \f
512 /* Common operations on the compiled pattern. */
513
514 /* Store NUMBER in two contiguous bytes starting at DESTINATION. */
515
516 #define STORE_NUMBER(destination, number) \
517 do { \
518 (destination)[0] = (number) & 0377; \
519 (destination)[1] = (number) >> 8; \
520 } while (0)
521
522 /* Same as STORE_NUMBER, except increment DESTINATION to
523 the byte after where the number is stored. Therefore, DESTINATION
524 must be an lvalue. */
525
526 #define STORE_NUMBER_AND_INCR(destination, number) \
527 do { \
528 STORE_NUMBER (destination, number); \
529 (destination) += 2; \
530 } while (0)
531
532 /* Put into DESTINATION a number stored in two contiguous bytes starting
533 at SOURCE. */
534
535 #define EXTRACT_NUMBER(destination, source) \
536 do { \
537 (destination) = *(source) & 0377; \
538 (destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8; \
539 } while (0)
540
541 #ifdef DEBUG
542 static void
543 extract_number (dest, source)
544 int *dest;
545 unsigned char *source;
546 {
547 int temp = SIGN_EXTEND_CHAR (*(source + 1));
548 *dest = *source & 0377;
549 *dest += temp << 8;
550 }
551
552 #ifndef EXTRACT_MACROS /* To debug the macros. */
553 #undef EXTRACT_NUMBER
554 #define EXTRACT_NUMBER(dest, src) extract_number (&dest, src)
555 #endif /* not EXTRACT_MACROS */
556
557 #endif /* DEBUG */
558
559 /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
560 SOURCE must be an lvalue. */
561
562 #define EXTRACT_NUMBER_AND_INCR(destination, source) \
563 do { \
564 EXTRACT_NUMBER (destination, source); \
565 (source) += 2; \
566 } while (0)
567
568 #ifdef DEBUG
569 static void
570 extract_number_and_incr (destination, source)
571 int *destination;
572 unsigned char **source;
573 {
574 extract_number (destination, *source);
575 *source += 2;
576 }
577
578 #ifndef EXTRACT_MACROS
579 #undef EXTRACT_NUMBER_AND_INCR
580 #define EXTRACT_NUMBER_AND_INCR(dest, src) \
581 extract_number_and_incr (&dest, &src)
582 #endif /* not EXTRACT_MACROS */
583
584 #endif /* DEBUG */
585 \f
586 /* Store a multibyte character in three contiguous bytes starting
587 DESTINATION, and increment DESTINATION to the byte after where the
588 character is stored. Therefore, DESTINATION must be an lvalue. */
589
590 #define STORE_CHARACTER_AND_INCR(destination, character) \
591 do { \
592 (destination)[0] = (character) & 0377; \
593 (destination)[1] = ((character) >> 8) & 0377; \
594 (destination)[2] = (character) >> 16; \
595 (destination) += 3; \
596 } while (0)
597
598 /* Put into DESTINATION a character stored in three contiguous bytes
599 starting at SOURCE. */
600
601 #define EXTRACT_CHARACTER(destination, source) \
602 do { \
603 (destination) = ((source)[0] \
604 | ((source)[1] << 8) \
605 | ((source)[2] << 16)); \
606 } while (0)
607
608
609 /* Macros for charset. */
610
611 /* Size of bitmap of charset P in bytes. P is a start of charset,
612 i.e. *P is (re_opcode_t) charset or (re_opcode_t) charset_not. */
613 #define CHARSET_BITMAP_SIZE(p) ((p)[1] & 0x7F)
614
615 /* Nonzero if charset P has range table. */
616 #define CHARSET_RANGE_TABLE_EXISTS_P(p) ((p)[1] & 0x80)
617
618 /* Return the address of range table of charset P. But not the start
619 of table itself, but the before where the number of ranges is
620 stored. `2 +' means to skip re_opcode_t and size of bitmap. */
621 #define CHARSET_RANGE_TABLE(p) (&(p)[2 + CHARSET_BITMAP_SIZE (p)])
622
623 /* Test if C is listed in the bitmap of charset P. */
624 #define CHARSET_LOOKUP_BITMAP(p, c) \
625 ((c) < CHARSET_BITMAP_SIZE (p) * BYTEWIDTH \
626 && (p)[2 + (c) / BYTEWIDTH] & (1 << ((c) % BYTEWIDTH)))
627
628 /* Return the address of end of RANGE_TABLE. COUNT is number of
629 ranges (which is a pair of (start, end)) in the RANGE_TABLE. `* 2'
630 is start of range and end of range. `* 3' is size of each start
631 and end. */
632 #define CHARSET_RANGE_TABLE_END(range_table, count) \
633 ((range_table) + (count) * 2 * 3)
634
635 /* Test if C is in RANGE_TABLE. A flag NOT is negated if C is in.
636 COUNT is number of ranges in RANGE_TABLE. */
637 #define CHARSET_LOOKUP_RANGE_TABLE_RAW(not, c, range_table, count) \
638 do \
639 { \
640 int range_start, range_end; \
641 unsigned char *p; \
642 unsigned char *range_table_end \
643 = CHARSET_RANGE_TABLE_END ((range_table), (count)); \
644 \
645 for (p = (range_table); p < range_table_end; p += 2 * 3) \
646 { \
647 EXTRACT_CHARACTER (range_start, p); \
648 EXTRACT_CHARACTER (range_end, p + 3); \
649 \
650 if (range_start <= (c) && (c) <= range_end) \
651 { \
652 (not) = !(not); \
653 break; \
654 } \
655 } \
656 } \
657 while (0)
658
659 /* Test if C is in range table of CHARSET. The flag NOT is negated if
660 C is listed in it. */
661 #define CHARSET_LOOKUP_RANGE_TABLE(not, c, charset) \
662 do \
663 { \
664 /* Number of ranges in range table. */ \
665 int count; \
666 unsigned char *range_table = CHARSET_RANGE_TABLE (charset); \
667 \
668 EXTRACT_NUMBER_AND_INCR (count, range_table); \
669 CHARSET_LOOKUP_RANGE_TABLE_RAW ((not), (c), range_table, count); \
670 } \
671 while (0)
672 \f
673 /* If DEBUG is defined, Regex prints many voluminous messages about what
674 it is doing (if the variable `debug' is nonzero). If linked with the
675 main program in `iregex.c', you can enter patterns and strings
676 interactively. And if linked with the main program in `main.c' and
677 the other test files, you can run the already-written tests. */
678
679 #ifdef DEBUG
680
681 /* We use standard I/O for debugging. */
682 #include <stdio.h>
683
684 /* It is useful to test things that ``must'' be true when debugging. */
685 #include <assert.h>
686
687 static int debug = 0;
688
689 #define DEBUG_STATEMENT(e) e
690 #define DEBUG_PRINT1(x) if (debug) printf (x)
691 #define DEBUG_PRINT2(x1, x2) if (debug) printf (x1, x2)
692 #define DEBUG_PRINT3(x1, x2, x3) if (debug) printf (x1, x2, x3)
693 #define DEBUG_PRINT4(x1, x2, x3, x4) if (debug) printf (x1, x2, x3, x4)
694 #define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) \
695 if (debug) print_partial_compiled_pattern (s, e)
696 #define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) \
697 if (debug) print_double_string (w, s1, sz1, s2, sz2)
698
699
700 /* Print the fastmap in human-readable form. */
701
702 void
703 print_fastmap (fastmap)
704 char *fastmap;
705 {
706 unsigned was_a_range = 0;
707 unsigned i = 0;
708
709 while (i < (1 << BYTEWIDTH))
710 {
711 if (fastmap[i++])
712 {
713 was_a_range = 0;
714 putchar (i - 1);
715 while (i < (1 << BYTEWIDTH) && fastmap[i])
716 {
717 was_a_range = 1;
718 i++;
719 }
720 if (was_a_range)
721 {
722 printf ("-");
723 putchar (i - 1);
724 }
725 }
726 }
727 putchar ('\n');
728 }
729
730
731 /* Print a compiled pattern string in human-readable form, starting at
732 the START pointer into it and ending just before the pointer END. */
733
734 void
735 print_partial_compiled_pattern (start, end)
736 unsigned char *start;
737 unsigned char *end;
738 {
739 int mcnt, mcnt2;
740 unsigned char *p = start;
741 unsigned char *pend = end;
742
743 if (start == NULL)
744 {
745 printf ("(null)\n");
746 return;
747 }
748
749 /* Loop over pattern commands. */
750 while (p < pend)
751 {
752 printf ("%d:\t", p - start);
753
754 switch ((re_opcode_t) *p++)
755 {
756 case no_op:
757 printf ("/no_op");
758 break;
759
760 case exactn:
761 mcnt = *p++;
762 printf ("/exactn/%d", mcnt);
763 do
764 {
765 putchar ('/');
766 putchar (*p++);
767 }
768 while (--mcnt);
769 break;
770
771 case start_memory:
772 mcnt = *p++;
773 printf ("/start_memory/%d/%d", mcnt, *p++);
774 break;
775
776 case stop_memory:
777 mcnt = *p++;
778 printf ("/stop_memory/%d/%d", mcnt, *p++);
779 break;
780
781 case duplicate:
782 printf ("/duplicate/%d", *p++);
783 break;
784
785 case anychar:
786 printf ("/anychar");
787 break;
788
789 case charset:
790 case charset_not:
791 {
792 register int c, last = -100;
793 register int in_range = 0;
794
795 printf ("/charset [%s",
796 (re_opcode_t) *(p - 1) == charset_not ? "^" : "");
797
798 assert (p + *p < pend);
799
800 for (c = 0; c < 256; c++)
801 if (c / 8 < *p
802 && (p[1 + (c/8)] & (1 << (c % 8))))
803 {
804 /* Are we starting a range? */
805 if (last + 1 == c && ! in_range)
806 {
807 putchar ('-');
808 in_range = 1;
809 }
810 /* Have we broken a range? */
811 else if (last + 1 != c && in_range)
812 {
813 putchar (last);
814 in_range = 0;
815 }
816
817 if (! in_range)
818 putchar (c);
819
820 last = c;
821 }
822
823 if (in_range)
824 putchar (last);
825
826 putchar (']');
827
828 p += 1 + *p;
829 }
830 break;
831
832 case begline:
833 printf ("/begline");
834 break;
835
836 case endline:
837 printf ("/endline");
838 break;
839
840 case on_failure_jump:
841 extract_number_and_incr (&mcnt, &p);
842 printf ("/on_failure_jump to %d", p + mcnt - start);
843 break;
844
845 case on_failure_keep_string_jump:
846 extract_number_and_incr (&mcnt, &p);
847 printf ("/on_failure_keep_string_jump to %d", p + mcnt - start);
848 break;
849
850 case dummy_failure_jump:
851 extract_number_and_incr (&mcnt, &p);
852 printf ("/dummy_failure_jump to %d", p + mcnt - start);
853 break;
854
855 case push_dummy_failure:
856 printf ("/push_dummy_failure");
857 break;
858
859 case maybe_pop_jump:
860 extract_number_and_incr (&mcnt, &p);
861 printf ("/maybe_pop_jump to %d", p + mcnt - start);
862 break;
863
864 case pop_failure_jump:
865 extract_number_and_incr (&mcnt, &p);
866 printf ("/pop_failure_jump to %d", p + mcnt - start);
867 break;
868
869 case jump_past_alt:
870 extract_number_and_incr (&mcnt, &p);
871 printf ("/jump_past_alt to %d", p + mcnt - start);
872 break;
873
874 case jump:
875 extract_number_and_incr (&mcnt, &p);
876 printf ("/jump to %d", p + mcnt - start);
877 break;
878
879 case succeed_n:
880 extract_number_and_incr (&mcnt, &p);
881 extract_number_and_incr (&mcnt2, &p);
882 printf ("/succeed_n to %d, %d times", p + mcnt - start, mcnt2);
883 break;
884
885 case jump_n:
886 extract_number_and_incr (&mcnt, &p);
887 extract_number_and_incr (&mcnt2, &p);
888 printf ("/jump_n to %d, %d times", p + mcnt - start, mcnt2);
889 break;
890
891 case set_number_at:
892 extract_number_and_incr (&mcnt, &p);
893 extract_number_and_incr (&mcnt2, &p);
894 printf ("/set_number_at location %d to %d", p + mcnt - start, mcnt2);
895 break;
896
897 case wordbound:
898 printf ("/wordbound");
899 break;
900
901 case notwordbound:
902 printf ("/notwordbound");
903 break;
904
905 case wordbeg:
906 printf ("/wordbeg");
907 break;
908
909 case wordend:
910 printf ("/wordend");
911
912 #ifdef emacs
913 case before_dot:
914 printf ("/before_dot");
915 break;
916
917 case at_dot:
918 printf ("/at_dot");
919 break;
920
921 case after_dot:
922 printf ("/after_dot");
923 break;
924
925 case syntaxspec:
926 printf ("/syntaxspec");
927 mcnt = *p++;
928 printf ("/%d", mcnt);
929 break;
930
931 case notsyntaxspec:
932 printf ("/notsyntaxspec");
933 mcnt = *p++;
934 printf ("/%d", mcnt);
935 break;
936 #endif /* emacs */
937
938 case wordchar:
939 printf ("/wordchar");
940 break;
941
942 case notwordchar:
943 printf ("/notwordchar");
944 break;
945
946 case begbuf:
947 printf ("/begbuf");
948 break;
949
950 case endbuf:
951 printf ("/endbuf");
952 break;
953
954 default:
955 printf ("?%d", *(p-1));
956 }
957
958 putchar ('\n');
959 }
960
961 printf ("%d:\tend of pattern.\n", p - start);
962 }
963
964
965 void
966 print_compiled_pattern (bufp)
967 struct re_pattern_buffer *bufp;
968 {
969 unsigned char *buffer = bufp->buffer;
970
971 print_partial_compiled_pattern (buffer, buffer + bufp->used);
972 printf ("%d bytes used/%d bytes allocated.\n", bufp->used, bufp->allocated);
973
974 if (bufp->fastmap_accurate && bufp->fastmap)
975 {
976 printf ("fastmap: ");
977 print_fastmap (bufp->fastmap);
978 }
979
980 printf ("re_nsub: %d\t", bufp->re_nsub);
981 printf ("regs_alloc: %d\t", bufp->regs_allocated);
982 printf ("can_be_null: %d\t", bufp->can_be_null);
983 printf ("newline_anchor: %d\n", bufp->newline_anchor);
984 printf ("no_sub: %d\t", bufp->no_sub);
985 printf ("not_bol: %d\t", bufp->not_bol);
986 printf ("not_eol: %d\t", bufp->not_eol);
987 printf ("syntax: %d\n", bufp->syntax);
988 /* Perhaps we should print the translate table? */
989 }
990
991
992 void
993 print_double_string (where, string1, size1, string2, size2)
994 const char *where;
995 const char *string1;
996 const char *string2;
997 int size1;
998 int size2;
999 {
1000 unsigned this_char;
1001
1002 if (where == NULL)
1003 printf ("(null)");
1004 else
1005 {
1006 if (FIRST_STRING_P (where))
1007 {
1008 for (this_char = where - string1; this_char < size1; this_char++)
1009 putchar (string1[this_char]);
1010
1011 where = string2;
1012 }
1013
1014 for (this_char = where - string2; this_char < size2; this_char++)
1015 putchar (string2[this_char]);
1016 }
1017 }
1018
1019 #else /* not DEBUG */
1020
1021 #undef assert
1022 #define assert(e)
1023
1024 #define DEBUG_STATEMENT(e)
1025 #define DEBUG_PRINT1(x)
1026 #define DEBUG_PRINT2(x1, x2)
1027 #define DEBUG_PRINT3(x1, x2, x3)
1028 #define DEBUG_PRINT4(x1, x2, x3, x4)
1029 #define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
1030 #define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
1031
1032 #endif /* not DEBUG */
1033 \f
1034 /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
1035 also be assigned to arbitrarily: each pattern buffer stores its own
1036 syntax, so it can be changed between regex compilations. */
1037 /* This has no initializer because initialized variables in Emacs
1038 become read-only after dumping. */
1039 reg_syntax_t re_syntax_options;
1040
1041
1042 /* Specify the precise syntax of regexps for compilation. This provides
1043 for compatibility for various utilities which historically have
1044 different, incompatible syntaxes.
1045
1046 The argument SYNTAX is a bit mask comprised of the various bits
1047 defined in regex.h. We return the old syntax. */
1048
1049 reg_syntax_t
1050 re_set_syntax (syntax)
1051 reg_syntax_t syntax;
1052 {
1053 reg_syntax_t ret = re_syntax_options;
1054
1055 re_syntax_options = syntax;
1056 return ret;
1057 }
1058 \f
1059 /* This table gives an error message for each of the error codes listed
1060 in regex.h. Obviously the order here has to be same as there.
1061 POSIX doesn't require that we do anything for REG_NOERROR,
1062 but why not be nice? */
1063
1064 static const char *re_error_msgid[] =
1065 {
1066 gettext_noop ("Success"), /* REG_NOERROR */
1067 gettext_noop ("No match"), /* REG_NOMATCH */
1068 gettext_noop ("Invalid regular expression"), /* REG_BADPAT */
1069 gettext_noop ("Invalid collation character"), /* REG_ECOLLATE */
1070 gettext_noop ("Invalid character class name"), /* REG_ECTYPE */
1071 gettext_noop ("Trailing backslash"), /* REG_EESCAPE */
1072 gettext_noop ("Invalid back reference"), /* REG_ESUBREG */
1073 gettext_noop ("Unmatched [ or [^"), /* REG_EBRACK */
1074 gettext_noop ("Unmatched ( or \\("), /* REG_EPAREN */
1075 gettext_noop ("Unmatched \\{"), /* REG_EBRACE */
1076 gettext_noop ("Invalid content of \\{\\}"), /* REG_BADBR */
1077 gettext_noop ("Invalid range end"), /* REG_ERANGE */
1078 gettext_noop ("Memory exhausted"), /* REG_ESPACE */
1079 gettext_noop ("Invalid preceding regular expression"), /* REG_BADRPT */
1080 gettext_noop ("Premature end of regular expression"), /* REG_EEND */
1081 gettext_noop ("Regular expression too big"), /* REG_ESIZE */
1082 gettext_noop ("Unmatched ) or \\)"), /* REG_ERPAREN */
1083 };
1084 \f
1085 /* Avoiding alloca during matching, to placate r_alloc. */
1086
1087 /* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
1088 searching and matching functions should not call alloca. On some
1089 systems, alloca is implemented in terms of malloc, and if we're
1090 using the relocating allocator routines, then malloc could cause a
1091 relocation, which might (if the strings being searched are in the
1092 ralloc heap) shift the data out from underneath the regexp
1093 routines.
1094
1095 Here's another reason to avoid allocation: Emacs
1096 processes input from X in a signal handler; processing X input may
1097 call malloc; if input arrives while a matching routine is calling
1098 malloc, then we're scrod. But Emacs can't just block input while
1099 calling matching routines; then we don't notice interrupts when
1100 they come in. So, Emacs blocks input around all regexp calls
1101 except the matching calls, which it leaves unprotected, in the
1102 faith that they will not malloc. */
1103
1104 /* Normally, this is fine. */
1105 #define MATCH_MAY_ALLOCATE
1106
1107 /* When using GNU C, we are not REALLY using the C alloca, no matter
1108 what config.h may say. So don't take precautions for it. */
1109 #ifdef __GNUC__
1110 #undef C_ALLOCA
1111 #endif
1112
1113 /* The match routines may not allocate if (1) they would do it with malloc
1114 and (2) it's not safe for them to use malloc.
1115 Note that if REL_ALLOC is defined, matching would not use malloc for the
1116 failure stack, but we would still use it for the register vectors;
1117 so REL_ALLOC should not affect this. */
1118 #if (defined (C_ALLOCA) || defined (REGEX_MALLOC)) && defined (emacs)
1119 #undef MATCH_MAY_ALLOCATE
1120 #endif
1121
1122 \f
1123 /* Failure stack declarations and macros; both re_compile_fastmap and
1124 re_match_2 use a failure stack. These have to be macros because of
1125 REGEX_ALLOCATE_STACK. */
1126
1127
1128 /* Approximate number of failure points for which to initially allocate space
1129 when matching. If this number is exceeded, we allocate more
1130 space, so it is not a hard limit. */
1131 #ifndef INIT_FAILURE_ALLOC
1132 #define INIT_FAILURE_ALLOC 20
1133 #endif
1134
1135 /* Roughly the maximum number of failure points on the stack. Would be
1136 exactly that if always used TYPICAL_FAILURE_SIZE items each time we failed.
1137 This is a variable only so users of regex can assign to it; we never
1138 change it ourselves. */
1139 #if defined (MATCH_MAY_ALLOCATE)
1140 /* Note that 4400 is enough to cause a crash on Alpha OSF/1,
1141 whose default stack limit is 2mb. In order for a larger
1142 value to work reliably, you have to try to make it accord
1143 with the process stack limit. */
1144 int re_max_failures = 40000;
1145 #else
1146 int re_max_failures = 4000;
1147 #endif
1148
1149 union fail_stack_elt
1150 {
1151 unsigned char *pointer;
1152 int integer;
1153 };
1154
1155 typedef union fail_stack_elt fail_stack_elt_t;
1156
1157 typedef struct
1158 {
1159 fail_stack_elt_t *stack;
1160 unsigned size;
1161 unsigned avail; /* Offset of next open position. */
1162 } fail_stack_type;
1163
1164 #define FAIL_STACK_EMPTY() (fail_stack.avail == 0)
1165 #define FAIL_STACK_PTR_EMPTY() (fail_stack_ptr->avail == 0)
1166 #define FAIL_STACK_FULL() (fail_stack.avail == fail_stack.size)
1167
1168
1169 /* Define macros to initialize and free the failure stack.
1170 Do `return -2' if the alloc fails. */
1171
1172 #ifdef MATCH_MAY_ALLOCATE
1173 #define INIT_FAIL_STACK() \
1174 do { \
1175 fail_stack.stack = (fail_stack_elt_t *) \
1176 REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * TYPICAL_FAILURE_SIZE \
1177 * sizeof (fail_stack_elt_t)); \
1178 \
1179 if (fail_stack.stack == NULL) \
1180 return -2; \
1181 \
1182 fail_stack.size = INIT_FAILURE_ALLOC; \
1183 fail_stack.avail = 0; \
1184 } while (0)
1185
1186 #define RESET_FAIL_STACK() REGEX_FREE_STACK (fail_stack.stack)
1187 #else
1188 #define INIT_FAIL_STACK() \
1189 do { \
1190 fail_stack.avail = 0; \
1191 } while (0)
1192
1193 #define RESET_FAIL_STACK()
1194 #endif
1195
1196
1197 /* Double the size of FAIL_STACK, up to a limit
1198 which allows approximately `re_max_failures' items.
1199
1200 Return 1 if succeeds, and 0 if either ran out of memory
1201 allocating space for it or it was already too large.
1202
1203 REGEX_REALLOCATE_STACK requires `destination' be declared. */
1204
1205 /* Factor to increase the failure stack size by
1206 when we increase it.
1207 This used to be 2, but 2 was too wasteful
1208 because the old discarded stacks added up to as much space
1209 were as ultimate, maximum-size stack. */
1210 #define FAIL_STACK_GROWTH_FACTOR 4
1211
1212 #define GROW_FAIL_STACK(fail_stack) \
1213 (((fail_stack).size * sizeof (fail_stack_elt_t) \
1214 >= re_max_failures * TYPICAL_FAILURE_SIZE) \
1215 ? 0 \
1216 : ((fail_stack).stack \
1217 = (fail_stack_elt_t *) \
1218 REGEX_REALLOCATE_STACK ((fail_stack).stack, \
1219 (fail_stack).size * sizeof (fail_stack_elt_t), \
1220 MIN (re_max_failures * TYPICAL_FAILURE_SIZE, \
1221 ((fail_stack).size * sizeof (fail_stack_elt_t) \
1222 * FAIL_STACK_GROWTH_FACTOR))), \
1223 \
1224 (fail_stack).stack == NULL \
1225 ? 0 \
1226 : ((fail_stack).size \
1227 = (MIN (re_max_failures * TYPICAL_FAILURE_SIZE, \
1228 ((fail_stack).size * sizeof (fail_stack_elt_t) \
1229 * FAIL_STACK_GROWTH_FACTOR)) \
1230 / sizeof (fail_stack_elt_t)), \
1231 1)))
1232
1233
1234 /* Push pointer POINTER on FAIL_STACK.
1235 Return 1 if was able to do so and 0 if ran out of memory allocating
1236 space to do so. */
1237 #define PUSH_PATTERN_OP(POINTER, FAIL_STACK) \
1238 ((FAIL_STACK_FULL () \
1239 && !GROW_FAIL_STACK (FAIL_STACK)) \
1240 ? 0 \
1241 : ((FAIL_STACK).stack[(FAIL_STACK).avail++].pointer = POINTER, \
1242 1))
1243
1244 /* Push a pointer value onto the failure stack.
1245 Assumes the variable `fail_stack'. Probably should only
1246 be called from within `PUSH_FAILURE_POINT'. */
1247 #define PUSH_FAILURE_POINTER(item) \
1248 fail_stack.stack[fail_stack.avail++].pointer = (unsigned char *) (item)
1249
1250 /* This pushes an integer-valued item onto the failure stack.
1251 Assumes the variable `fail_stack'. Probably should only
1252 be called from within `PUSH_FAILURE_POINT'. */
1253 #define PUSH_FAILURE_INT(item) \
1254 fail_stack.stack[fail_stack.avail++].integer = (item)
1255
1256 /* Push a fail_stack_elt_t value onto the failure stack.
1257 Assumes the variable `fail_stack'. Probably should only
1258 be called from within `PUSH_FAILURE_POINT'. */
1259 #define PUSH_FAILURE_ELT(item) \
1260 fail_stack.stack[fail_stack.avail++] = (item)
1261
1262 /* These three POP... operations complement the three PUSH... operations.
1263 All assume that `fail_stack' is nonempty. */
1264 #define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
1265 #define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
1266 #define POP_FAILURE_ELT() fail_stack.stack[--fail_stack.avail]
1267
1268 /* Used to omit pushing failure point id's when we're not debugging. */
1269 #ifdef DEBUG
1270 #define DEBUG_PUSH PUSH_FAILURE_INT
1271 #define DEBUG_POP(item_addr) *(item_addr) = POP_FAILURE_INT ()
1272 #else
1273 #define DEBUG_PUSH(item)
1274 #define DEBUG_POP(item_addr)
1275 #endif
1276
1277
1278 /* Push the information about the state we will need
1279 if we ever fail back to it.
1280
1281 Requires variables fail_stack, regstart, regend, reg_info, and
1282 num_regs be declared. GROW_FAIL_STACK requires `destination' be
1283 declared.
1284
1285 Does `return FAILURE_CODE' if runs out of memory. */
1286
1287 #define PUSH_FAILURE_POINT(pattern_place, string_place, failure_code) \
1288 do { \
1289 char *destination; \
1290 /* Must be int, so when we don't save any registers, the arithmetic \
1291 of 0 + -1 isn't done as unsigned. */ \
1292 int this_reg; \
1293 \
1294 DEBUG_STATEMENT (failure_id++); \
1295 DEBUG_STATEMENT (nfailure_points_pushed++); \
1296 DEBUG_PRINT2 ("\nPUSH_FAILURE_POINT #%u:\n", failure_id); \
1297 DEBUG_PRINT2 (" Before push, next avail: %d\n", (fail_stack).avail);\
1298 DEBUG_PRINT2 (" size: %d\n", (fail_stack).size);\
1299 \
1300 DEBUG_PRINT2 (" slots needed: %d\n", NUM_FAILURE_ITEMS); \
1301 DEBUG_PRINT2 (" available: %d\n", REMAINING_AVAIL_SLOTS); \
1302 \
1303 /* Ensure we have enough space allocated for what we will push. */ \
1304 while (REMAINING_AVAIL_SLOTS < NUM_FAILURE_ITEMS) \
1305 { \
1306 if (!GROW_FAIL_STACK (fail_stack)) \
1307 return failure_code; \
1308 \
1309 DEBUG_PRINT2 ("\n Doubled stack; size now: %d\n", \
1310 (fail_stack).size); \
1311 DEBUG_PRINT2 (" slots available: %d\n", REMAINING_AVAIL_SLOTS);\
1312 } \
1313 \
1314 /* Push the info, starting with the registers. */ \
1315 DEBUG_PRINT1 ("\n"); \
1316 \
1317 if (1) \
1318 for (this_reg = lowest_active_reg; this_reg <= highest_active_reg; \
1319 this_reg++) \
1320 { \
1321 DEBUG_PRINT2 (" Pushing reg: %d\n", this_reg); \
1322 DEBUG_STATEMENT (num_regs_pushed++); \
1323 \
1324 DEBUG_PRINT2 (" start: 0x%x\n", regstart[this_reg]); \
1325 PUSH_FAILURE_POINTER (regstart[this_reg]); \
1326 \
1327 DEBUG_PRINT2 (" end: 0x%x\n", regend[this_reg]); \
1328 PUSH_FAILURE_POINTER (regend[this_reg]); \
1329 \
1330 DEBUG_PRINT2 (" info: 0x%x\n ", reg_info[this_reg]); \
1331 DEBUG_PRINT2 (" match_null=%d", \
1332 REG_MATCH_NULL_STRING_P (reg_info[this_reg])); \
1333 DEBUG_PRINT2 (" active=%d", IS_ACTIVE (reg_info[this_reg])); \
1334 DEBUG_PRINT2 (" matched_something=%d", \
1335 MATCHED_SOMETHING (reg_info[this_reg])); \
1336 DEBUG_PRINT2 (" ever_matched=%d", \
1337 EVER_MATCHED_SOMETHING (reg_info[this_reg])); \
1338 DEBUG_PRINT1 ("\n"); \
1339 PUSH_FAILURE_ELT (reg_info[this_reg].word); \
1340 } \
1341 \
1342 DEBUG_PRINT2 (" Pushing low active reg: %d\n", lowest_active_reg);\
1343 PUSH_FAILURE_INT (lowest_active_reg); \
1344 \
1345 DEBUG_PRINT2 (" Pushing high active reg: %d\n", highest_active_reg);\
1346 PUSH_FAILURE_INT (highest_active_reg); \
1347 \
1348 DEBUG_PRINT2 (" Pushing pattern 0x%x: ", pattern_place); \
1349 DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern_place, pend); \
1350 PUSH_FAILURE_POINTER (pattern_place); \
1351 \
1352 DEBUG_PRINT2 (" Pushing string 0x%x: `", string_place); \
1353 DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2, \
1354 size2); \
1355 DEBUG_PRINT1 ("'\n"); \
1356 PUSH_FAILURE_POINTER (string_place); \
1357 \
1358 DEBUG_PRINT2 (" Pushing failure id: %u\n", failure_id); \
1359 DEBUG_PUSH (failure_id); \
1360 } while (0)
1361
1362 /* This is the number of items that are pushed and popped on the stack
1363 for each register. */
1364 #define NUM_REG_ITEMS 3
1365
1366 /* Individual items aside from the registers. */
1367 #ifdef DEBUG
1368 #define NUM_NONREG_ITEMS 5 /* Includes failure point id. */
1369 #else
1370 #define NUM_NONREG_ITEMS 4
1371 #endif
1372
1373 /* Estimate the size of data pushed by a typical failure stack entry.
1374 An estimate is all we need, because all we use this for
1375 is to choose a limit for how big to make the failure stack. */
1376
1377 #define TYPICAL_FAILURE_SIZE 20
1378
1379 /* This is how many items we actually use for a failure point.
1380 It depends on the regexp. */
1381 #define NUM_FAILURE_ITEMS \
1382 (((0 \
1383 ? 0 : highest_active_reg - lowest_active_reg + 1) \
1384 * NUM_REG_ITEMS) \
1385 + NUM_NONREG_ITEMS)
1386
1387 /* How many items can still be added to the stack without overflowing it. */
1388 #define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
1389
1390
1391 /* Pops what PUSH_FAIL_STACK pushes.
1392
1393 We restore into the parameters, all of which should be lvalues:
1394 STR -- the saved data position.
1395 PAT -- the saved pattern position.
1396 LOW_REG, HIGH_REG -- the highest and lowest active registers.
1397 REGSTART, REGEND -- arrays of string positions.
1398 REG_INFO -- array of information about each subexpression.
1399
1400 Also assumes the variables `fail_stack' and (if debugging), `bufp',
1401 `pend', `string1', `size1', `string2', and `size2'. */
1402
1403 #define POP_FAILURE_POINT(str, pat, low_reg, high_reg, regstart, regend, reg_info)\
1404 { \
1405 DEBUG_STATEMENT (fail_stack_elt_t failure_id;) \
1406 int this_reg; \
1407 const unsigned char *string_temp; \
1408 \
1409 assert (!FAIL_STACK_EMPTY ()); \
1410 \
1411 /* Remove failure points and point to how many regs pushed. */ \
1412 DEBUG_PRINT1 ("POP_FAILURE_POINT:\n"); \
1413 DEBUG_PRINT2 (" Before pop, next avail: %d\n", fail_stack.avail); \
1414 DEBUG_PRINT2 (" size: %d\n", fail_stack.size); \
1415 \
1416 assert (fail_stack.avail >= NUM_NONREG_ITEMS); \
1417 \
1418 DEBUG_POP (&failure_id); \
1419 DEBUG_PRINT2 (" Popping failure id: %u\n", failure_id); \
1420 \
1421 /* If the saved string location is NULL, it came from an \
1422 on_failure_keep_string_jump opcode, and we want to throw away the \
1423 saved NULL, thus retaining our current position in the string. */ \
1424 string_temp = POP_FAILURE_POINTER (); \
1425 if (string_temp != NULL) \
1426 str = (const char *) string_temp; \
1427 \
1428 DEBUG_PRINT2 (" Popping string 0x%x: `", str); \
1429 DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2); \
1430 DEBUG_PRINT1 ("'\n"); \
1431 \
1432 pat = (unsigned char *) POP_FAILURE_POINTER (); \
1433 DEBUG_PRINT2 (" Popping pattern 0x%x: ", pat); \
1434 DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend); \
1435 \
1436 /* Restore register info. */ \
1437 high_reg = (unsigned) POP_FAILURE_INT (); \
1438 DEBUG_PRINT2 (" Popping high active reg: %d\n", high_reg); \
1439 \
1440 low_reg = (unsigned) POP_FAILURE_INT (); \
1441 DEBUG_PRINT2 (" Popping low active reg: %d\n", low_reg); \
1442 \
1443 if (1) \
1444 for (this_reg = high_reg; this_reg >= low_reg; this_reg--) \
1445 { \
1446 DEBUG_PRINT2 (" Popping reg: %d\n", this_reg); \
1447 \
1448 reg_info[this_reg].word = POP_FAILURE_ELT (); \
1449 DEBUG_PRINT2 (" info: 0x%x\n", reg_info[this_reg]); \
1450 \
1451 regend[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1452 DEBUG_PRINT2 (" end: 0x%x\n", regend[this_reg]); \
1453 \
1454 regstart[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1455 DEBUG_PRINT2 (" start: 0x%x\n", regstart[this_reg]); \
1456 } \
1457 else \
1458 { \
1459 for (this_reg = highest_active_reg; this_reg > high_reg; this_reg--) \
1460 { \
1461 reg_info[this_reg].word.integer = 0; \
1462 regend[this_reg] = 0; \
1463 regstart[this_reg] = 0; \
1464 } \
1465 highest_active_reg = high_reg; \
1466 } \
1467 \
1468 set_regs_matched_done = 0; \
1469 DEBUG_STATEMENT (nfailure_points_popped++); \
1470 } /* POP_FAILURE_POINT */
1471
1472
1473 \f
1474 /* Structure for per-register (a.k.a. per-group) information.
1475 Other register information, such as the
1476 starting and ending positions (which are addresses), and the list of
1477 inner groups (which is a bits list) are maintained in separate
1478 variables.
1479
1480 We are making a (strictly speaking) nonportable assumption here: that
1481 the compiler will pack our bit fields into something that fits into
1482 the type of `word', i.e., is something that fits into one item on the
1483 failure stack. */
1484
1485 typedef union
1486 {
1487 fail_stack_elt_t word;
1488 struct
1489 {
1490 /* This field is one if this group can match the empty string,
1491 zero if not. If not yet determined, `MATCH_NULL_UNSET_VALUE'. */
1492 #define MATCH_NULL_UNSET_VALUE 3
1493 unsigned match_null_string_p : 2;
1494 unsigned is_active : 1;
1495 unsigned matched_something : 1;
1496 unsigned ever_matched_something : 1;
1497 } bits;
1498 } register_info_type;
1499
1500 #define REG_MATCH_NULL_STRING_P(R) ((R).bits.match_null_string_p)
1501 #define IS_ACTIVE(R) ((R).bits.is_active)
1502 #define MATCHED_SOMETHING(R) ((R).bits.matched_something)
1503 #define EVER_MATCHED_SOMETHING(R) ((R).bits.ever_matched_something)
1504
1505
1506 /* Call this when have matched a real character; it sets `matched' flags
1507 for the subexpressions which we are currently inside. Also records
1508 that those subexprs have matched. */
1509 #define SET_REGS_MATCHED() \
1510 do \
1511 { \
1512 if (!set_regs_matched_done) \
1513 { \
1514 unsigned r; \
1515 set_regs_matched_done = 1; \
1516 for (r = lowest_active_reg; r <= highest_active_reg; r++) \
1517 { \
1518 MATCHED_SOMETHING (reg_info[r]) \
1519 = EVER_MATCHED_SOMETHING (reg_info[r]) \
1520 = 1; \
1521 } \
1522 } \
1523 } \
1524 while (0)
1525
1526 /* Registers are set to a sentinel when they haven't yet matched. */
1527 static char reg_unset_dummy;
1528 #define REG_UNSET_VALUE (&reg_unset_dummy)
1529 #define REG_UNSET(e) ((e) == REG_UNSET_VALUE)
1530 \f
1531 /* Subroutine declarations and macros for regex_compile. */
1532
1533 static void store_op1 (), store_op2 ();
1534 static void insert_op1 (), insert_op2 ();
1535 static boolean at_begline_loc_p (), at_endline_loc_p ();
1536 static boolean group_in_compile_stack ();
1537 static reg_errcode_t compile_range ();
1538
1539 /* Fetch the next character in the uncompiled pattern---translating it
1540 if necessary. Also cast from a signed character in the constant
1541 string passed to us by the user to an unsigned char that we can use
1542 as an array index (in, e.g., `translate'). */
1543 #ifndef PATFETCH
1544 #define PATFETCH(c) \
1545 do {if (p == pend) return REG_EEND; \
1546 c = (unsigned char) *p++; \
1547 if (RE_TRANSLATE_P (translate)) c = RE_TRANSLATE (translate, c); \
1548 } while (0)
1549 #endif
1550
1551 /* Fetch the next character in the uncompiled pattern, with no
1552 translation. */
1553 #define PATFETCH_RAW(c) \
1554 do {if (p == pend) return REG_EEND; \
1555 c = (unsigned char) *p++; \
1556 } while (0)
1557
1558 /* Go backwards one character in the pattern. */
1559 #define PATUNFETCH p--
1560
1561
1562 /* If `translate' is non-null, return translate[D], else just D. We
1563 cast the subscript to translate because some data is declared as
1564 `char *', to avoid warnings when a string constant is passed. But
1565 when we use a character as a subscript we must make it unsigned. */
1566 #ifndef TRANSLATE
1567 #define TRANSLATE(d) \
1568 (RE_TRANSLATE_P (translate) \
1569 ? (unsigned) RE_TRANSLATE (translate, (unsigned) (d)) : (d))
1570 #endif
1571
1572
1573 /* Macros for outputting the compiled pattern into `buffer'. */
1574
1575 /* If the buffer isn't allocated when it comes in, use this. */
1576 #define INIT_BUF_SIZE 32
1577
1578 /* Make sure we have at least N more bytes of space in buffer. */
1579 #define GET_BUFFER_SPACE(n) \
1580 while (b - bufp->buffer + (n) > bufp->allocated) \
1581 EXTEND_BUFFER ()
1582
1583 /* Make sure we have one more byte of buffer space and then add C to it. */
1584 #define BUF_PUSH(c) \
1585 do { \
1586 GET_BUFFER_SPACE (1); \
1587 *b++ = (unsigned char) (c); \
1588 } while (0)
1589
1590
1591 /* Ensure we have two more bytes of buffer space and then append C1 and C2. */
1592 #define BUF_PUSH_2(c1, c2) \
1593 do { \
1594 GET_BUFFER_SPACE (2); \
1595 *b++ = (unsigned char) (c1); \
1596 *b++ = (unsigned char) (c2); \
1597 } while (0)
1598
1599
1600 /* As with BUF_PUSH_2, except for three bytes. */
1601 #define BUF_PUSH_3(c1, c2, c3) \
1602 do { \
1603 GET_BUFFER_SPACE (3); \
1604 *b++ = (unsigned char) (c1); \
1605 *b++ = (unsigned char) (c2); \
1606 *b++ = (unsigned char) (c3); \
1607 } while (0)
1608
1609
1610 /* Store a jump with opcode OP at LOC to location TO. We store a
1611 relative address offset by the three bytes the jump itself occupies. */
1612 #define STORE_JUMP(op, loc, to) \
1613 store_op1 (op, loc, (to) - (loc) - 3)
1614
1615 /* Likewise, for a two-argument jump. */
1616 #define STORE_JUMP2(op, loc, to, arg) \
1617 store_op2 (op, loc, (to) - (loc) - 3, arg)
1618
1619 /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
1620 #define INSERT_JUMP(op, loc, to) \
1621 insert_op1 (op, loc, (to) - (loc) - 3, b)
1622
1623 /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
1624 #define INSERT_JUMP2(op, loc, to, arg) \
1625 insert_op2 (op, loc, (to) - (loc) - 3, arg, b)
1626
1627
1628 /* This is not an arbitrary limit: the arguments which represent offsets
1629 into the pattern are two bytes long. So if 2^16 bytes turns out to
1630 be too small, many things would have to change. */
1631 #define MAX_BUF_SIZE (1L << 16)
1632
1633
1634 /* Extend the buffer by twice its current size via realloc and
1635 reset the pointers that pointed into the old block to point to the
1636 correct places in the new one. If extending the buffer results in it
1637 being larger than MAX_BUF_SIZE, then flag memory exhausted. */
1638 #define EXTEND_BUFFER() \
1639 do { \
1640 unsigned char *old_buffer = bufp->buffer; \
1641 if (bufp->allocated == MAX_BUF_SIZE) \
1642 return REG_ESIZE; \
1643 bufp->allocated <<= 1; \
1644 if (bufp->allocated > MAX_BUF_SIZE) \
1645 bufp->allocated = MAX_BUF_SIZE; \
1646 bufp->buffer = (unsigned char *) realloc (bufp->buffer, bufp->allocated);\
1647 if (bufp->buffer == NULL) \
1648 return REG_ESPACE; \
1649 /* If the buffer moved, move all the pointers into it. */ \
1650 if (old_buffer != bufp->buffer) \
1651 { \
1652 b = (b - old_buffer) + bufp->buffer; \
1653 begalt = (begalt - old_buffer) + bufp->buffer; \
1654 if (fixup_alt_jump) \
1655 fixup_alt_jump = (fixup_alt_jump - old_buffer) + bufp->buffer;\
1656 if (laststart) \
1657 laststart = (laststart - old_buffer) + bufp->buffer; \
1658 if (pending_exact) \
1659 pending_exact = (pending_exact - old_buffer) + bufp->buffer; \
1660 } \
1661 } while (0)
1662
1663
1664 /* Since we have one byte reserved for the register number argument to
1665 {start,stop}_memory, the maximum number of groups we can report
1666 things about is what fits in that byte. */
1667 #define MAX_REGNUM 255
1668
1669 /* But patterns can have more than `MAX_REGNUM' registers. We just
1670 ignore the excess. */
1671 typedef unsigned regnum_t;
1672
1673
1674 /* Macros for the compile stack. */
1675
1676 /* Since offsets can go either forwards or backwards, this type needs to
1677 be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
1678 typedef int pattern_offset_t;
1679
1680 typedef struct
1681 {
1682 pattern_offset_t begalt_offset;
1683 pattern_offset_t fixup_alt_jump;
1684 pattern_offset_t inner_group_offset;
1685 pattern_offset_t laststart_offset;
1686 regnum_t regnum;
1687 } compile_stack_elt_t;
1688
1689
1690 typedef struct
1691 {
1692 compile_stack_elt_t *stack;
1693 unsigned size;
1694 unsigned avail; /* Offset of next open position. */
1695 } compile_stack_type;
1696
1697
1698 #define INIT_COMPILE_STACK_SIZE 32
1699
1700 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
1701 #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
1702
1703 /* The next available element. */
1704 #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
1705
1706
1707 /* Structure to manage work area for range table. */
1708 struct range_table_work_area
1709 {
1710 int *table; /* actual work area. */
1711 int allocated; /* allocated size for work area in bytes. */
1712 int used; /* actually used size in words. */
1713 };
1714
1715 /* Make sure that WORK_AREA can hold more N multibyte characters. */
1716 #define EXTEND_RANGE_TABLE_WORK_AREA(work_area, n) \
1717 do { \
1718 if (((work_area).used + (n)) * sizeof (int) > (work_area).allocated) \
1719 { \
1720 (work_area).allocated += 16 * sizeof (int); \
1721 if ((work_area).table) \
1722 (work_area).table \
1723 = (int *) realloc ((work_area).table, (work_area).allocated); \
1724 else \
1725 (work_area).table \
1726 = (int *) malloc ((work_area).allocated); \
1727 if ((work_area).table == 0) \
1728 FREE_STACK_RETURN (REG_ESPACE); \
1729 } \
1730 } while (0)
1731
1732 /* Set a range (RANGE_START, RANGE_END) to WORK_AREA. */
1733 #define SET_RANGE_TABLE_WORK_AREA(work_area, range_start, range_end) \
1734 do { \
1735 EXTEND_RANGE_TABLE_WORK_AREA ((work_area), 2); \
1736 (work_area).table[(work_area).used++] = (range_start); \
1737 (work_area).table[(work_area).used++] = (range_end); \
1738 } while (0)
1739
1740 /* Free allocated memory for WORK_AREA. */
1741 #define FREE_RANGE_TABLE_WORK_AREA(work_area) \
1742 do { \
1743 if ((work_area).table) \
1744 free ((work_area).table); \
1745 } while (0)
1746
1747 #define CLEAR_RANGE_TABLE_WORK_USED(work_area) ((work_area).used = 0)
1748 #define RANGE_TABLE_WORK_USED(work_area) ((work_area).used)
1749 #define RANGE_TABLE_WORK_ELT(work_area, i) ((work_area).table[i])
1750
1751
1752 /* Set the bit for character C in a list. */
1753 #define SET_LIST_BIT(c) \
1754 (b[((unsigned char) (c)) / BYTEWIDTH] \
1755 |= 1 << (((unsigned char) c) % BYTEWIDTH))
1756
1757
1758 /* Get the next unsigned number in the uncompiled pattern. */
1759 #define GET_UNSIGNED_NUMBER(num) \
1760 { if (p != pend) \
1761 { \
1762 PATFETCH (c); \
1763 while (ISDIGIT (c)) \
1764 { \
1765 if (num < 0) \
1766 num = 0; \
1767 num = num * 10 + c - '0'; \
1768 if (p == pend) \
1769 break; \
1770 PATFETCH (c); \
1771 } \
1772 } \
1773 }
1774
1775 #define CHAR_CLASS_MAX_LENGTH 6 /* Namely, `xdigit'. */
1776
1777 #define IS_CHAR_CLASS(string) \
1778 (STREQ (string, "alpha") || STREQ (string, "upper") \
1779 || STREQ (string, "lower") || STREQ (string, "digit") \
1780 || STREQ (string, "alnum") || STREQ (string, "xdigit") \
1781 || STREQ (string, "space") || STREQ (string, "print") \
1782 || STREQ (string, "punct") || STREQ (string, "graph") \
1783 || STREQ (string, "cntrl") || STREQ (string, "blank"))
1784 \f
1785 #ifndef MATCH_MAY_ALLOCATE
1786
1787 /* If we cannot allocate large objects within re_match_2_internal,
1788 we make the fail stack and register vectors global.
1789 The fail stack, we grow to the maximum size when a regexp
1790 is compiled.
1791 The register vectors, we adjust in size each time we
1792 compile a regexp, according to the number of registers it needs. */
1793
1794 static fail_stack_type fail_stack;
1795
1796 /* Size with which the following vectors are currently allocated.
1797 That is so we can make them bigger as needed,
1798 but never make them smaller. */
1799 static int regs_allocated_size;
1800
1801 static const char ** regstart, ** regend;
1802 static const char ** old_regstart, ** old_regend;
1803 static const char **best_regstart, **best_regend;
1804 static register_info_type *reg_info;
1805 static const char **reg_dummy;
1806 static register_info_type *reg_info_dummy;
1807
1808 /* Make the register vectors big enough for NUM_REGS registers,
1809 but don't make them smaller. */
1810
1811 static
1812 regex_grow_registers (num_regs)
1813 int num_regs;
1814 {
1815 if (num_regs > regs_allocated_size)
1816 {
1817 RETALLOC_IF (regstart, num_regs, const char *);
1818 RETALLOC_IF (regend, num_regs, const char *);
1819 RETALLOC_IF (old_regstart, num_regs, const char *);
1820 RETALLOC_IF (old_regend, num_regs, const char *);
1821 RETALLOC_IF (best_regstart, num_regs, const char *);
1822 RETALLOC_IF (best_regend, num_regs, const char *);
1823 RETALLOC_IF (reg_info, num_regs, register_info_type);
1824 RETALLOC_IF (reg_dummy, num_regs, const char *);
1825 RETALLOC_IF (reg_info_dummy, num_regs, register_info_type);
1826
1827 regs_allocated_size = num_regs;
1828 }
1829 }
1830
1831 #endif /* not MATCH_MAY_ALLOCATE */
1832 \f
1833 /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
1834 Returns one of error codes defined in `regex.h', or zero for success.
1835
1836 Assumes the `allocated' (and perhaps `buffer') and `translate'
1837 fields are set in BUFP on entry.
1838
1839 If it succeeds, results are put in BUFP (if it returns an error, the
1840 contents of BUFP are undefined):
1841 `buffer' is the compiled pattern;
1842 `syntax' is set to SYNTAX;
1843 `used' is set to the length of the compiled pattern;
1844 `fastmap_accurate' is zero;
1845 `re_nsub' is the number of subexpressions in PATTERN;
1846 `not_bol' and `not_eol' are zero;
1847
1848 The `fastmap' and `newline_anchor' fields are neither
1849 examined nor set. */
1850
1851 /* Return, freeing storage we allocated. */
1852 #define FREE_STACK_RETURN(value) \
1853 do { \
1854 FREE_RANGE_TABLE_WORK_AREA (range_table_work); \
1855 free (compile_stack.stack); \
1856 return value; \
1857 } while (0)
1858
1859 static reg_errcode_t
1860 regex_compile (pattern, size, syntax, bufp)
1861 const char *pattern;
1862 int size;
1863 reg_syntax_t syntax;
1864 struct re_pattern_buffer *bufp;
1865 {
1866 /* We fetch characters from PATTERN here. Even though PATTERN is
1867 `char *' (i.e., signed), we declare these variables as unsigned, so
1868 they can be reliably used as array indices. */
1869 register unsigned int c, c1;
1870
1871 /* A random temporary spot in PATTERN. */
1872 const char *p1;
1873
1874 /* Points to the end of the buffer, where we should append. */
1875 register unsigned char *b;
1876
1877 /* Keeps track of unclosed groups. */
1878 compile_stack_type compile_stack;
1879
1880 /* Points to the current (ending) position in the pattern. */
1881 #ifdef AIX
1882 /* `const' makes AIX compiler fail. */
1883 char *p = pattern;
1884 #else
1885 const char *p = pattern;
1886 #endif
1887 const char *pend = pattern + size;
1888
1889 /* How to translate the characters in the pattern. */
1890 RE_TRANSLATE_TYPE translate = bufp->translate;
1891
1892 /* Address of the count-byte of the most recently inserted `exactn'
1893 command. This makes it possible to tell if a new exact-match
1894 character can be added to that command or if the character requires
1895 a new `exactn' command. */
1896 unsigned char *pending_exact = 0;
1897
1898 /* Address of start of the most recently finished expression.
1899 This tells, e.g., postfix * where to find the start of its
1900 operand. Reset at the beginning of groups and alternatives. */
1901 unsigned char *laststart = 0;
1902
1903 /* Address of beginning of regexp, or inside of last group. */
1904 unsigned char *begalt;
1905
1906 /* Place in the uncompiled pattern (i.e., the {) to
1907 which to go back if the interval is invalid. */
1908 const char *beg_interval;
1909
1910 /* Address of the place where a forward jump should go to the end of
1911 the containing expression. Each alternative of an `or' -- except the
1912 last -- ends with a forward jump of this sort. */
1913 unsigned char *fixup_alt_jump = 0;
1914
1915 /* Counts open-groups as they are encountered. Remembered for the
1916 matching close-group on the compile stack, so the same register
1917 number is put in the stop_memory as the start_memory. */
1918 regnum_t regnum = 0;
1919
1920 /* Work area for range table of charset. */
1921 struct range_table_work_area range_table_work;
1922
1923 #ifdef DEBUG
1924 DEBUG_PRINT1 ("\nCompiling pattern: ");
1925 if (debug)
1926 {
1927 unsigned debug_count;
1928
1929 for (debug_count = 0; debug_count < size; debug_count++)
1930 putchar (pattern[debug_count]);
1931 putchar ('\n');
1932 }
1933 #endif /* DEBUG */
1934
1935 /* Initialize the compile stack. */
1936 compile_stack.stack = TALLOC (INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
1937 if (compile_stack.stack == NULL)
1938 return REG_ESPACE;
1939
1940 compile_stack.size = INIT_COMPILE_STACK_SIZE;
1941 compile_stack.avail = 0;
1942
1943 range_table_work.table = 0;
1944 range_table_work.allocated = 0;
1945
1946 /* Initialize the pattern buffer. */
1947 bufp->syntax = syntax;
1948 bufp->fastmap_accurate = 0;
1949 bufp->not_bol = bufp->not_eol = 0;
1950
1951 /* Set `used' to zero, so that if we return an error, the pattern
1952 printer (for debugging) will think there's no pattern. We reset it
1953 at the end. */
1954 bufp->used = 0;
1955
1956 /* Always count groups, whether or not bufp->no_sub is set. */
1957 bufp->re_nsub = 0;
1958
1959 #ifdef emacs
1960 /* bufp->multibyte is set before regex_compile is called, so don't alter
1961 it. */
1962 #else /* not emacs */
1963 /* Nothing is recognized as a multibyte character. */
1964 bufp->multibyte = 0;
1965 #endif
1966
1967 #if !defined (emacs) && !defined (SYNTAX_TABLE)
1968 /* Initialize the syntax table. */
1969 init_syntax_once ();
1970 #endif
1971
1972 if (bufp->allocated == 0)
1973 {
1974 if (bufp->buffer)
1975 { /* If zero allocated, but buffer is non-null, try to realloc
1976 enough space. This loses if buffer's address is bogus, but
1977 that is the user's responsibility. */
1978 RETALLOC (bufp->buffer, INIT_BUF_SIZE, unsigned char);
1979 }
1980 else
1981 { /* Caller did not allocate a buffer. Do it for them. */
1982 bufp->buffer = TALLOC (INIT_BUF_SIZE, unsigned char);
1983 }
1984 if (!bufp->buffer) FREE_STACK_RETURN (REG_ESPACE);
1985
1986 bufp->allocated = INIT_BUF_SIZE;
1987 }
1988
1989 begalt = b = bufp->buffer;
1990
1991 /* Loop through the uncompiled pattern until we're at the end. */
1992 while (p != pend)
1993 {
1994 PATFETCH (c);
1995
1996 switch (c)
1997 {
1998 case '^':
1999 {
2000 if ( /* If at start of pattern, it's an operator. */
2001 p == pattern + 1
2002 /* If context independent, it's an operator. */
2003 || syntax & RE_CONTEXT_INDEP_ANCHORS
2004 /* Otherwise, depends on what's come before. */
2005 || at_begline_loc_p (pattern, p, syntax))
2006 BUF_PUSH (begline);
2007 else
2008 goto normal_char;
2009 }
2010 break;
2011
2012
2013 case '$':
2014 {
2015 if ( /* If at end of pattern, it's an operator. */
2016 p == pend
2017 /* If context independent, it's an operator. */
2018 || syntax & RE_CONTEXT_INDEP_ANCHORS
2019 /* Otherwise, depends on what's next. */
2020 || at_endline_loc_p (p, pend, syntax))
2021 BUF_PUSH (endline);
2022 else
2023 goto normal_char;
2024 }
2025 break;
2026
2027
2028 case '+':
2029 case '?':
2030 if ((syntax & RE_BK_PLUS_QM)
2031 || (syntax & RE_LIMITED_OPS))
2032 goto normal_char;
2033 handle_plus:
2034 case '*':
2035 /* If there is no previous pattern... */
2036 if (!laststart)
2037 {
2038 if (syntax & RE_CONTEXT_INVALID_OPS)
2039 FREE_STACK_RETURN (REG_BADRPT);
2040 else if (!(syntax & RE_CONTEXT_INDEP_OPS))
2041 goto normal_char;
2042 }
2043
2044 {
2045 /* Are we optimizing this jump? */
2046 boolean keep_string_p = false;
2047
2048 /* 1 means zero (many) matches is allowed. */
2049 char zero_times_ok = 0, many_times_ok = 0;
2050
2051 /* If there is a sequence of repetition chars, collapse it
2052 down to just one (the right one). We can't combine
2053 interval operators with these because of, e.g., `a{2}*',
2054 which should only match an even number of `a's. */
2055
2056 for (;;)
2057 {
2058 zero_times_ok |= c != '+';
2059 many_times_ok |= c != '?';
2060
2061 if (p == pend)
2062 break;
2063
2064 PATFETCH (c);
2065
2066 if (c == '*'
2067 || (!(syntax & RE_BK_PLUS_QM) && (c == '+' || c == '?')))
2068 ;
2069
2070 else if (syntax & RE_BK_PLUS_QM && c == '\\')
2071 {
2072 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2073
2074 PATFETCH (c1);
2075 if (!(c1 == '+' || c1 == '?'))
2076 {
2077 PATUNFETCH;
2078 PATUNFETCH;
2079 break;
2080 }
2081
2082 c = c1;
2083 }
2084 else
2085 {
2086 PATUNFETCH;
2087 break;
2088 }
2089
2090 /* If we get here, we found another repeat character. */
2091 }
2092
2093 /* Star, etc. applied to an empty pattern is equivalent
2094 to an empty pattern. */
2095 if (!laststart)
2096 break;
2097
2098 /* Now we know whether or not zero matches is allowed
2099 and also whether or not two or more matches is allowed. */
2100 if (many_times_ok)
2101 { /* More than one repetition is allowed, so put in at the
2102 end a backward relative jump from `b' to before the next
2103 jump we're going to put in below (which jumps from
2104 laststart to after this jump).
2105
2106 But if we are at the `*' in the exact sequence `.*\n',
2107 insert an unconditional jump backwards to the .,
2108 instead of the beginning of the loop. This way we only
2109 push a failure point once, instead of every time
2110 through the loop. */
2111 assert (p - 1 > pattern);
2112
2113 /* Allocate the space for the jump. */
2114 GET_BUFFER_SPACE (3);
2115
2116 /* We know we are not at the first character of the pattern,
2117 because laststart was nonzero. And we've already
2118 incremented `p', by the way, to be the character after
2119 the `*'. Do we have to do something analogous here
2120 for null bytes, because of RE_DOT_NOT_NULL? */
2121 if (TRANSLATE ((unsigned char)*(p - 2)) == TRANSLATE ('.')
2122 && zero_times_ok
2123 && p < pend
2124 && TRANSLATE ((unsigned char)*p) == TRANSLATE ('\n')
2125 && !(syntax & RE_DOT_NEWLINE))
2126 { /* We have .*\n. */
2127 STORE_JUMP (jump, b, laststart);
2128 keep_string_p = true;
2129 }
2130 else
2131 /* Anything else. */
2132 STORE_JUMP (maybe_pop_jump, b, laststart - 3);
2133
2134 /* We've added more stuff to the buffer. */
2135 b += 3;
2136 }
2137
2138 /* On failure, jump from laststart to b + 3, which will be the
2139 end of the buffer after this jump is inserted. */
2140 GET_BUFFER_SPACE (3);
2141 INSERT_JUMP (keep_string_p ? on_failure_keep_string_jump
2142 : on_failure_jump,
2143 laststart, b + 3);
2144 pending_exact = 0;
2145 b += 3;
2146
2147 if (!zero_times_ok)
2148 {
2149 /* At least one repetition is required, so insert a
2150 `dummy_failure_jump' before the initial
2151 `on_failure_jump' instruction of the loop. This
2152 effects a skip over that instruction the first time
2153 we hit that loop. */
2154 GET_BUFFER_SPACE (3);
2155 INSERT_JUMP (dummy_failure_jump, laststart, laststart + 6);
2156 b += 3;
2157 }
2158 }
2159 break;
2160
2161
2162 case '.':
2163 laststart = b;
2164 BUF_PUSH (anychar);
2165 break;
2166
2167
2168 case '[':
2169 {
2170 CLEAR_RANGE_TABLE_WORK_USED (range_table_work);
2171
2172 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2173
2174 /* Ensure that we have enough space to push a charset: the
2175 opcode, the length count, and the bitset; 34 bytes in all. */
2176 GET_BUFFER_SPACE (34);
2177
2178 laststart = b;
2179
2180 /* We test `*p == '^' twice, instead of using an if
2181 statement, so we only need one BUF_PUSH. */
2182 BUF_PUSH (*p == '^' ? charset_not : charset);
2183 if (*p == '^')
2184 p++;
2185
2186 /* Remember the first position in the bracket expression. */
2187 p1 = p;
2188
2189 /* Push the number of bytes in the bitmap. */
2190 BUF_PUSH ((1 << BYTEWIDTH) / BYTEWIDTH);
2191
2192 /* Clear the whole map. */
2193 bzero (b, (1 << BYTEWIDTH) / BYTEWIDTH);
2194
2195 /* charset_not matches newline according to a syntax bit. */
2196 if ((re_opcode_t) b[-2] == charset_not
2197 && (syntax & RE_HAT_LISTS_NOT_NEWLINE))
2198 SET_LIST_BIT ('\n');
2199
2200 /* Read in characters and ranges, setting map bits. */
2201 for (;;)
2202 {
2203 int len;
2204 boolean escaped_char = false;
2205
2206 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2207
2208 PATFETCH (c);
2209
2210 /* \ might escape characters inside [...] and [^...]. */
2211 if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\')
2212 {
2213 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2214
2215 PATFETCH (c);
2216 escaped_char = true;
2217 }
2218 else
2219 {
2220 /* Could be the end of the bracket expression. If it's
2221 not (i.e., when the bracket expression is `[]' so
2222 far), the ']' character bit gets set way below. */
2223 if (c == ']' && p != p1 + 1)
2224 break;
2225 }
2226
2227 /* If C indicates start of multibyte char, get the
2228 actual character code in C, and set the pattern
2229 pointer P to the next character boundary. */
2230 if (bufp->multibyte && BASE_LEADING_CODE_P (c))
2231 {
2232 PATUNFETCH;
2233 c = STRING_CHAR_AND_LENGTH (p, pend - p, len);
2234 p += len;
2235 }
2236 /* What should we do for the character which is
2237 greater than 0x7F, but not BASE_LEADING_CODE_P?
2238 XXX */
2239
2240 /* See if we're at the beginning of a possible character
2241 class. */
2242
2243 else if (!escaped_char &&
2244 syntax & RE_CHAR_CLASSES && c == '[' && *p == ':')
2245 {
2246 /* Leave room for the null. */
2247 char str[CHAR_CLASS_MAX_LENGTH + 1];
2248
2249 PATFETCH (c);
2250 c1 = 0;
2251
2252 /* If pattern is `[[:'. */
2253 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2254
2255 for (;;)
2256 {
2257 PATFETCH (c);
2258 if (c == ':' || c == ']' || p == pend
2259 || c1 == CHAR_CLASS_MAX_LENGTH)
2260 break;
2261 str[c1++] = c;
2262 }
2263 str[c1] = '\0';
2264
2265 /* If isn't a word bracketed by `[:' and `:]':
2266 undo the ending character, the letters, and
2267 leave the leading `:' and `[' (but set bits for
2268 them). */
2269 if (c == ':' && *p == ']')
2270 {
2271 int ch;
2272 boolean is_alnum = STREQ (str, "alnum");
2273 boolean is_alpha = STREQ (str, "alpha");
2274 boolean is_blank = STREQ (str, "blank");
2275 boolean is_cntrl = STREQ (str, "cntrl");
2276 boolean is_digit = STREQ (str, "digit");
2277 boolean is_graph = STREQ (str, "graph");
2278 boolean is_lower = STREQ (str, "lower");
2279 boolean is_print = STREQ (str, "print");
2280 boolean is_punct = STREQ (str, "punct");
2281 boolean is_space = STREQ (str, "space");
2282 boolean is_upper = STREQ (str, "upper");
2283 boolean is_xdigit = STREQ (str, "xdigit");
2284
2285 if (!IS_CHAR_CLASS (str))
2286 FREE_STACK_RETURN (REG_ECTYPE);
2287
2288 /* Throw away the ] at the end of the character
2289 class. */
2290 PATFETCH (c);
2291
2292 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2293
2294 for (ch = 0; ch < 1 << BYTEWIDTH; ch++)
2295 {
2296 int translated = TRANSLATE (ch);
2297 /* This was split into 3 if's to
2298 avoid an arbitrary limit in some compiler. */
2299 if ( (is_alnum && ISALNUM (ch))
2300 || (is_alpha && ISALPHA (ch))
2301 || (is_blank && ISBLANK (ch))
2302 || (is_cntrl && ISCNTRL (ch)))
2303 SET_LIST_BIT (translated);
2304 if ( (is_digit && ISDIGIT (ch))
2305 || (is_graph && ISGRAPH (ch))
2306 || (is_lower && ISLOWER (ch))
2307 || (is_print && ISPRINT (ch)))
2308 SET_LIST_BIT (translated);
2309 if ( (is_punct && ISPUNCT (ch))
2310 || (is_space && ISSPACE (ch))
2311 || (is_upper && ISUPPER (ch))
2312 || (is_xdigit && ISXDIGIT (ch)))
2313 SET_LIST_BIT (translated);
2314 }
2315
2316 /* Repeat the loop. */
2317 continue;
2318 }
2319 else
2320 {
2321 c1++;
2322 while (c1--)
2323 PATUNFETCH;
2324 SET_LIST_BIT ('[');
2325
2326 /* Because the `:' may starts the range, we
2327 can't simply set bit and repeat the loop.
2328 Instead, just set it to C and handle below. */
2329 c = ':';
2330 }
2331 }
2332
2333 if (p < pend && p[0] == '-' && p[1] != ']')
2334 {
2335
2336 /* Discard the `-'. */
2337 PATFETCH (c1);
2338
2339 /* Fetch the character which ends the range. */
2340 PATFETCH (c1);
2341 if (bufp->multibyte && BASE_LEADING_CODE_P (c1))
2342 {
2343 PATUNFETCH;
2344 c1 = STRING_CHAR_AND_LENGTH (p, pend - p, len);
2345 p += len;
2346 }
2347
2348 if (SINGLE_BYTE_CHAR_P (c)
2349 && ! SINGLE_BYTE_CHAR_P (c1))
2350 {
2351 /* Handle a range such as \177-\377 in multibyte mode.
2352 Split that into two ranges,,
2353 the low one ending at 0237, and the high one
2354 starting at ...040. */
2355 int c1_base = (c1 & ~0177) | 040;
2356 SET_RANGE_TABLE_WORK_AREA (range_table_work, c, c1);
2357 c1 = 0237;
2358 }
2359 else if (!SAME_CHARSET_P (c, c1))
2360 FREE_STACK_RETURN (REG_ERANGE);
2361 }
2362 else
2363 /* Range from C to C. */
2364 c1 = c;
2365
2366 /* Set the range ... */
2367 if (SINGLE_BYTE_CHAR_P (c))
2368 /* ... into bitmap. */
2369 {
2370 unsigned this_char;
2371 int range_start = c, range_end = c1;
2372
2373 /* If the start is after the end, the range is empty. */
2374 if (range_start > range_end)
2375 {
2376 if (syntax & RE_NO_EMPTY_RANGES)
2377 FREE_STACK_RETURN (REG_ERANGE);
2378 /* Else, repeat the loop. */
2379 }
2380 else
2381 {
2382 for (this_char = range_start; this_char <= range_end;
2383 this_char++)
2384 SET_LIST_BIT (TRANSLATE (this_char));
2385 }
2386 }
2387 else
2388 /* ... into range table. */
2389 SET_RANGE_TABLE_WORK_AREA (range_table_work, c, c1);
2390 }
2391
2392 /* Discard any (non)matching list bytes that are all 0 at the
2393 end of the map. Decrease the map-length byte too. */
2394 while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
2395 b[-1]--;
2396 b += b[-1];
2397
2398 /* Build real range table from work area. */
2399 if (RANGE_TABLE_WORK_USED (range_table_work))
2400 {
2401 int i;
2402 int used = RANGE_TABLE_WORK_USED (range_table_work);
2403
2404 /* Allocate space for COUNT + RANGE_TABLE. Needs two
2405 bytes for COUNT and three bytes for each character. */
2406 GET_BUFFER_SPACE (2 + used * 3);
2407
2408 /* Indicate the existence of range table. */
2409 laststart[1] |= 0x80;
2410
2411 STORE_NUMBER_AND_INCR (b, used / 2);
2412 for (i = 0; i < used; i++)
2413 STORE_CHARACTER_AND_INCR
2414 (b, RANGE_TABLE_WORK_ELT (range_table_work, i));
2415 }
2416 }
2417 break;
2418
2419
2420 case '(':
2421 if (syntax & RE_NO_BK_PARENS)
2422 goto handle_open;
2423 else
2424 goto normal_char;
2425
2426
2427 case ')':
2428 if (syntax & RE_NO_BK_PARENS)
2429 goto handle_close;
2430 else
2431 goto normal_char;
2432
2433
2434 case '\n':
2435 if (syntax & RE_NEWLINE_ALT)
2436 goto handle_alt;
2437 else
2438 goto normal_char;
2439
2440
2441 case '|':
2442 if (syntax & RE_NO_BK_VBAR)
2443 goto handle_alt;
2444 else
2445 goto normal_char;
2446
2447
2448 case '{':
2449 if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
2450 goto handle_interval;
2451 else
2452 goto normal_char;
2453
2454
2455 case '\\':
2456 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2457
2458 /* Do not translate the character after the \, so that we can
2459 distinguish, e.g., \B from \b, even if we normally would
2460 translate, e.g., B to b. */
2461 PATFETCH_RAW (c);
2462
2463 switch (c)
2464 {
2465 case '(':
2466 if (syntax & RE_NO_BK_PARENS)
2467 goto normal_backslash;
2468
2469 handle_open:
2470 bufp->re_nsub++;
2471 regnum++;
2472
2473 if (COMPILE_STACK_FULL)
2474 {
2475 RETALLOC (compile_stack.stack, compile_stack.size << 1,
2476 compile_stack_elt_t);
2477 if (compile_stack.stack == NULL) return REG_ESPACE;
2478
2479 compile_stack.size <<= 1;
2480 }
2481
2482 /* These are the values to restore when we hit end of this
2483 group. They are all relative offsets, so that if the
2484 whole pattern moves because of realloc, they will still
2485 be valid. */
2486 COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
2487 COMPILE_STACK_TOP.fixup_alt_jump
2488 = fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
2489 COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
2490 COMPILE_STACK_TOP.regnum = regnum;
2491
2492 /* We will eventually replace the 0 with the number of
2493 groups inner to this one. But do not push a
2494 start_memory for groups beyond the last one we can
2495 represent in the compiled pattern. */
2496 if (regnum <= MAX_REGNUM)
2497 {
2498 COMPILE_STACK_TOP.inner_group_offset = b - bufp->buffer + 2;
2499 BUF_PUSH_3 (start_memory, regnum, 0);
2500 }
2501
2502 compile_stack.avail++;
2503
2504 fixup_alt_jump = 0;
2505 laststart = 0;
2506 begalt = b;
2507 /* If we've reached MAX_REGNUM groups, then this open
2508 won't actually generate any code, so we'll have to
2509 clear pending_exact explicitly. */
2510 pending_exact = 0;
2511 break;
2512
2513
2514 case ')':
2515 if (syntax & RE_NO_BK_PARENS) goto normal_backslash;
2516
2517 if (COMPILE_STACK_EMPTY)
2518 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
2519 goto normal_backslash;
2520 else
2521 FREE_STACK_RETURN (REG_ERPAREN);
2522
2523 handle_close:
2524 if (fixup_alt_jump)
2525 { /* Push a dummy failure point at the end of the
2526 alternative for a possible future
2527 `pop_failure_jump' to pop. See comments at
2528 `push_dummy_failure' in `re_match_2'. */
2529 BUF_PUSH (push_dummy_failure);
2530
2531 /* We allocated space for this jump when we assigned
2532 to `fixup_alt_jump', in the `handle_alt' case below. */
2533 STORE_JUMP (jump_past_alt, fixup_alt_jump, b - 1);
2534 }
2535
2536 /* See similar code for backslashed left paren above. */
2537 if (COMPILE_STACK_EMPTY)
2538 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
2539 goto normal_char;
2540 else
2541 FREE_STACK_RETURN (REG_ERPAREN);
2542
2543 /* Since we just checked for an empty stack above, this
2544 ``can't happen''. */
2545 assert (compile_stack.avail != 0);
2546 {
2547 /* We don't just want to restore into `regnum', because
2548 later groups should continue to be numbered higher,
2549 as in `(ab)c(de)' -- the second group is #2. */
2550 regnum_t this_group_regnum;
2551
2552 compile_stack.avail--;
2553 begalt = bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
2554 fixup_alt_jump
2555 = COMPILE_STACK_TOP.fixup_alt_jump
2556 ? bufp->buffer + COMPILE_STACK_TOP.fixup_alt_jump - 1
2557 : 0;
2558 laststart = bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
2559 this_group_regnum = COMPILE_STACK_TOP.regnum;
2560 /* If we've reached MAX_REGNUM groups, then this open
2561 won't actually generate any code, so we'll have to
2562 clear pending_exact explicitly. */
2563 pending_exact = 0;
2564
2565 /* We're at the end of the group, so now we know how many
2566 groups were inside this one. */
2567 if (this_group_regnum <= MAX_REGNUM)
2568 {
2569 unsigned char *inner_group_loc
2570 = bufp->buffer + COMPILE_STACK_TOP.inner_group_offset;
2571
2572 *inner_group_loc = regnum - this_group_regnum;
2573 BUF_PUSH_3 (stop_memory, this_group_regnum,
2574 regnum - this_group_regnum);
2575 }
2576 }
2577 break;
2578
2579
2580 case '|': /* `\|'. */
2581 if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
2582 goto normal_backslash;
2583 handle_alt:
2584 if (syntax & RE_LIMITED_OPS)
2585 goto normal_char;
2586
2587 /* Insert before the previous alternative a jump which
2588 jumps to this alternative if the former fails. */
2589 GET_BUFFER_SPACE (3);
2590 INSERT_JUMP (on_failure_jump, begalt, b + 6);
2591 pending_exact = 0;
2592 b += 3;
2593
2594 /* The alternative before this one has a jump after it
2595 which gets executed if it gets matched. Adjust that
2596 jump so it will jump to this alternative's analogous
2597 jump (put in below, which in turn will jump to the next
2598 (if any) alternative's such jump, etc.). The last such
2599 jump jumps to the correct final destination. A picture:
2600 _____ _____
2601 | | | |
2602 | v | v
2603 a | b | c
2604
2605 If we are at `b', then fixup_alt_jump right now points to a
2606 three-byte space after `a'. We'll put in the jump, set
2607 fixup_alt_jump to right after `b', and leave behind three
2608 bytes which we'll fill in when we get to after `c'. */
2609
2610 if (fixup_alt_jump)
2611 STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
2612
2613 /* Mark and leave space for a jump after this alternative,
2614 to be filled in later either by next alternative or
2615 when know we're at the end of a series of alternatives. */
2616 fixup_alt_jump = b;
2617 GET_BUFFER_SPACE (3);
2618 b += 3;
2619
2620 laststart = 0;
2621 begalt = b;
2622 break;
2623
2624
2625 case '{':
2626 /* If \{ is a literal. */
2627 if (!(syntax & RE_INTERVALS)
2628 /* If we're at `\{' and it's not the open-interval
2629 operator. */
2630 || ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
2631 || (p - 2 == pattern && p == pend))
2632 goto normal_backslash;
2633
2634 handle_interval:
2635 {
2636 /* If got here, then the syntax allows intervals. */
2637
2638 /* At least (most) this many matches must be made. */
2639 int lower_bound = -1, upper_bound = -1;
2640
2641 beg_interval = p - 1;
2642
2643 if (p == pend)
2644 {
2645 if (syntax & RE_NO_BK_BRACES)
2646 goto unfetch_interval;
2647 else
2648 FREE_STACK_RETURN (REG_EBRACE);
2649 }
2650
2651 GET_UNSIGNED_NUMBER (lower_bound);
2652
2653 if (c == ',')
2654 {
2655 GET_UNSIGNED_NUMBER (upper_bound);
2656 if (upper_bound < 0) upper_bound = RE_DUP_MAX;
2657 }
2658 else
2659 /* Interval such as `{1}' => match exactly once. */
2660 upper_bound = lower_bound;
2661
2662 if (lower_bound < 0 || upper_bound > RE_DUP_MAX
2663 || lower_bound > upper_bound)
2664 {
2665 if (syntax & RE_NO_BK_BRACES)
2666 goto unfetch_interval;
2667 else
2668 FREE_STACK_RETURN (REG_BADBR);
2669 }
2670
2671 if (!(syntax & RE_NO_BK_BRACES))
2672 {
2673 if (c != '\\') FREE_STACK_RETURN (REG_EBRACE);
2674
2675 PATFETCH (c);
2676 }
2677
2678 if (c != '}')
2679 {
2680 if (syntax & RE_NO_BK_BRACES)
2681 goto unfetch_interval;
2682 else
2683 FREE_STACK_RETURN (REG_BADBR);
2684 }
2685
2686 /* We just parsed a valid interval. */
2687
2688 /* If it's invalid to have no preceding re. */
2689 if (!laststart)
2690 {
2691 if (syntax & RE_CONTEXT_INVALID_OPS)
2692 FREE_STACK_RETURN (REG_BADRPT);
2693 else if (syntax & RE_CONTEXT_INDEP_OPS)
2694 laststart = b;
2695 else
2696 goto unfetch_interval;
2697 }
2698
2699 /* If the upper bound is zero, don't want to succeed at
2700 all; jump from `laststart' to `b + 3', which will be
2701 the end of the buffer after we insert the jump. */
2702 if (upper_bound == 0)
2703 {
2704 GET_BUFFER_SPACE (3);
2705 INSERT_JUMP (jump, laststart, b + 3);
2706 b += 3;
2707 }
2708
2709 /* Otherwise, we have a nontrivial interval. When
2710 we're all done, the pattern will look like:
2711 set_number_at <jump count> <upper bound>
2712 set_number_at <succeed_n count> <lower bound>
2713 succeed_n <after jump addr> <succeed_n count>
2714 <body of loop>
2715 jump_n <succeed_n addr> <jump count>
2716 (The upper bound and `jump_n' are omitted if
2717 `upper_bound' is 1, though.) */
2718 else
2719 { /* If the upper bound is > 1, we need to insert
2720 more at the end of the loop. */
2721 unsigned nbytes = 10 + (upper_bound > 1) * 10;
2722
2723 GET_BUFFER_SPACE (nbytes);
2724
2725 /* Initialize lower bound of the `succeed_n', even
2726 though it will be set during matching by its
2727 attendant `set_number_at' (inserted next),
2728 because `re_compile_fastmap' needs to know.
2729 Jump to the `jump_n' we might insert below. */
2730 INSERT_JUMP2 (succeed_n, laststart,
2731 b + 5 + (upper_bound > 1) * 5,
2732 lower_bound);
2733 b += 5;
2734
2735 /* Code to initialize the lower bound. Insert
2736 before the `succeed_n'. The `5' is the last two
2737 bytes of this `set_number_at', plus 3 bytes of
2738 the following `succeed_n'. */
2739 insert_op2 (set_number_at, laststart, 5, lower_bound, b);
2740 b += 5;
2741
2742 if (upper_bound > 1)
2743 { /* More than one repetition is allowed, so
2744 append a backward jump to the `succeed_n'
2745 that starts this interval.
2746
2747 When we've reached this during matching,
2748 we'll have matched the interval once, so
2749 jump back only `upper_bound - 1' times. */
2750 STORE_JUMP2 (jump_n, b, laststart + 5,
2751 upper_bound - 1);
2752 b += 5;
2753
2754 /* The location we want to set is the second
2755 parameter of the `jump_n'; that is `b-2' as
2756 an absolute address. `laststart' will be
2757 the `set_number_at' we're about to insert;
2758 `laststart+3' the number to set, the source
2759 for the relative address. But we are
2760 inserting into the middle of the pattern --
2761 so everything is getting moved up by 5.
2762 Conclusion: (b - 2) - (laststart + 3) + 5,
2763 i.e., b - laststart.
2764
2765 We insert this at the beginning of the loop
2766 so that if we fail during matching, we'll
2767 reinitialize the bounds. */
2768 insert_op2 (set_number_at, laststart, b - laststart,
2769 upper_bound - 1, b);
2770 b += 5;
2771 }
2772 }
2773 pending_exact = 0;
2774 beg_interval = NULL;
2775 }
2776 break;
2777
2778 unfetch_interval:
2779 /* If an invalid interval, match the characters as literals. */
2780 assert (beg_interval);
2781 p = beg_interval;
2782 beg_interval = NULL;
2783
2784 /* normal_char and normal_backslash need `c'. */
2785 PATFETCH (c);
2786
2787 if (!(syntax & RE_NO_BK_BRACES))
2788 {
2789 if (p > pattern && p[-1] == '\\')
2790 goto normal_backslash;
2791 }
2792 goto normal_char;
2793
2794 #ifdef emacs
2795 /* There is no way to specify the before_dot and after_dot
2796 operators. rms says this is ok. --karl */
2797 case '=':
2798 BUF_PUSH (at_dot);
2799 break;
2800
2801 case 's':
2802 laststart = b;
2803 PATFETCH (c);
2804 BUF_PUSH_2 (syntaxspec, syntax_spec_code[c]);
2805 break;
2806
2807 case 'S':
2808 laststart = b;
2809 PATFETCH (c);
2810 BUF_PUSH_2 (notsyntaxspec, syntax_spec_code[c]);
2811 break;
2812
2813 case 'c':
2814 laststart = b;
2815 PATFETCH_RAW (c);
2816 BUF_PUSH_2 (categoryspec, c);
2817 break;
2818
2819 case 'C':
2820 laststart = b;
2821 PATFETCH_RAW (c);
2822 BUF_PUSH_2 (notcategoryspec, c);
2823 break;
2824 #endif /* emacs */
2825
2826
2827 case 'w':
2828 laststart = b;
2829 BUF_PUSH (wordchar);
2830 break;
2831
2832
2833 case 'W':
2834 laststart = b;
2835 BUF_PUSH (notwordchar);
2836 break;
2837
2838
2839 case '<':
2840 BUF_PUSH (wordbeg);
2841 break;
2842
2843 case '>':
2844 BUF_PUSH (wordend);
2845 break;
2846
2847 case 'b':
2848 BUF_PUSH (wordbound);
2849 break;
2850
2851 case 'B':
2852 BUF_PUSH (notwordbound);
2853 break;
2854
2855 case '`':
2856 BUF_PUSH (begbuf);
2857 break;
2858
2859 case '\'':
2860 BUF_PUSH (endbuf);
2861 break;
2862
2863 case '1': case '2': case '3': case '4': case '5':
2864 case '6': case '7': case '8': case '9':
2865 if (syntax & RE_NO_BK_REFS)
2866 goto normal_char;
2867
2868 c1 = c - '0';
2869
2870 if (c1 > regnum)
2871 FREE_STACK_RETURN (REG_ESUBREG);
2872
2873 /* Can't back reference to a subexpression if inside of it. */
2874 if (group_in_compile_stack (compile_stack, c1))
2875 goto normal_char;
2876
2877 laststart = b;
2878 BUF_PUSH_2 (duplicate, c1);
2879 break;
2880
2881
2882 case '+':
2883 case '?':
2884 if (syntax & RE_BK_PLUS_QM)
2885 goto handle_plus;
2886 else
2887 goto normal_backslash;
2888
2889 default:
2890 normal_backslash:
2891 /* You might think it would be useful for \ to mean
2892 not to translate; but if we don't translate it
2893 it will never match anything. */
2894 c = TRANSLATE (c);
2895 goto normal_char;
2896 }
2897 break;
2898
2899
2900 default:
2901 /* Expects the character in `c'. */
2902 normal_char:
2903 p1 = p - 1; /* P1 points the head of C. */
2904 #ifdef emacs
2905 if (bufp->multibyte)
2906 {
2907 c = STRING_CHAR (p1, pend - p1);
2908 c = TRANSLATE (c);
2909 /* Set P to the next character boundary. */
2910 p += MULTIBYTE_FORM_LENGTH (p1, pend - p1) - 1;
2911 }
2912 #endif
2913 /* If no exactn currently being built. */
2914 if (!pending_exact
2915
2916 /* If last exactn not at current position. */
2917 || pending_exact + *pending_exact + 1 != b
2918
2919 /* We have only one byte following the exactn for the count. */
2920 || *pending_exact >= (1 << BYTEWIDTH) - (p - p1)
2921
2922 /* If followed by a repetition operator. */
2923 || (p != pend && (*p == '*' || *p == '^'))
2924 || ((syntax & RE_BK_PLUS_QM)
2925 ? p + 1 < pend && *p == '\\' && (p[1] == '+' || p[1] == '?')
2926 : p != pend && (*p == '+' || *p == '?'))
2927 || ((syntax & RE_INTERVALS)
2928 && ((syntax & RE_NO_BK_BRACES)
2929 ? p != pend && *p == '{'
2930 : p + 1 < pend && p[0] == '\\' && p[1] == '{')))
2931 {
2932 /* Start building a new exactn. */
2933
2934 laststart = b;
2935
2936 BUF_PUSH_2 (exactn, 0);
2937 pending_exact = b - 1;
2938 }
2939
2940 #ifdef emacs
2941 if (! SINGLE_BYTE_CHAR_P (c))
2942 {
2943 unsigned char work[4], *str;
2944 int i = CHAR_STRING (c, work, str);
2945 int j;
2946 for (j = 0; j < i; j++)
2947 {
2948 BUF_PUSH (str[j]);
2949 (*pending_exact)++;
2950 }
2951 }
2952 else
2953 #endif
2954 {
2955 BUF_PUSH (c);
2956 (*pending_exact)++;
2957 }
2958 break;
2959 } /* switch (c) */
2960 } /* while p != pend */
2961
2962
2963 /* Through the pattern now. */
2964
2965 if (fixup_alt_jump)
2966 STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
2967
2968 if (!COMPILE_STACK_EMPTY)
2969 FREE_STACK_RETURN (REG_EPAREN);
2970
2971 /* If we don't want backtracking, force success
2972 the first time we reach the end of the compiled pattern. */
2973 if (syntax & RE_NO_POSIX_BACKTRACKING)
2974 BUF_PUSH (succeed);
2975
2976 free (compile_stack.stack);
2977
2978 /* We have succeeded; set the length of the buffer. */
2979 bufp->used = b - bufp->buffer;
2980
2981 #ifdef DEBUG
2982 if (debug)
2983 {
2984 DEBUG_PRINT1 ("\nCompiled pattern: \n");
2985 print_compiled_pattern (bufp);
2986 }
2987 #endif /* DEBUG */
2988
2989 #ifndef MATCH_MAY_ALLOCATE
2990 /* Initialize the failure stack to the largest possible stack. This
2991 isn't necessary unless we're trying to avoid calling alloca in
2992 the search and match routines. */
2993 {
2994 int num_regs = bufp->re_nsub + 1;
2995
2996 if (fail_stack.size < re_max_failures * TYPICAL_FAILURE_SIZE)
2997 {
2998 fail_stack.size = re_max_failures * TYPICAL_FAILURE_SIZE;
2999
3000 #ifdef emacs
3001 if (! fail_stack.stack)
3002 fail_stack.stack
3003 = (fail_stack_elt_t *) xmalloc (fail_stack.size
3004 * sizeof (fail_stack_elt_t));
3005 else
3006 fail_stack.stack
3007 = (fail_stack_elt_t *) xrealloc (fail_stack.stack,
3008 (fail_stack.size
3009 * sizeof (fail_stack_elt_t)));
3010 #else /* not emacs */
3011 if (! fail_stack.stack)
3012 fail_stack.stack
3013 = (fail_stack_elt_t *) malloc (fail_stack.size
3014 * sizeof (fail_stack_elt_t));
3015 else
3016 fail_stack.stack
3017 = (fail_stack_elt_t *) realloc (fail_stack.stack,
3018 (fail_stack.size
3019 * sizeof (fail_stack_elt_t)));
3020 #endif /* not emacs */
3021 }
3022
3023 regex_grow_registers (num_regs);
3024 }
3025 #endif /* not MATCH_MAY_ALLOCATE */
3026
3027 return REG_NOERROR;
3028 } /* regex_compile */
3029 \f
3030 /* Subroutines for `regex_compile'. */
3031
3032 /* Store OP at LOC followed by two-byte integer parameter ARG. */
3033
3034 static void
3035 store_op1 (op, loc, arg)
3036 re_opcode_t op;
3037 unsigned char *loc;
3038 int arg;
3039 {
3040 *loc = (unsigned char) op;
3041 STORE_NUMBER (loc + 1, arg);
3042 }
3043
3044
3045 /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
3046
3047 static void
3048 store_op2 (op, loc, arg1, arg2)
3049 re_opcode_t op;
3050 unsigned char *loc;
3051 int arg1, arg2;
3052 {
3053 *loc = (unsigned char) op;
3054 STORE_NUMBER (loc + 1, arg1);
3055 STORE_NUMBER (loc + 3, arg2);
3056 }
3057
3058
3059 /* Copy the bytes from LOC to END to open up three bytes of space at LOC
3060 for OP followed by two-byte integer parameter ARG. */
3061
3062 static void
3063 insert_op1 (op, loc, arg, end)
3064 re_opcode_t op;
3065 unsigned char *loc;
3066 int arg;
3067 unsigned char *end;
3068 {
3069 register unsigned char *pfrom = end;
3070 register unsigned char *pto = end + 3;
3071
3072 while (pfrom != loc)
3073 *--pto = *--pfrom;
3074
3075 store_op1 (op, loc, arg);
3076 }
3077
3078
3079 /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
3080
3081 static void
3082 insert_op2 (op, loc, arg1, arg2, end)
3083 re_opcode_t op;
3084 unsigned char *loc;
3085 int arg1, arg2;
3086 unsigned char *end;
3087 {
3088 register unsigned char *pfrom = end;
3089 register unsigned char *pto = end + 5;
3090
3091 while (pfrom != loc)
3092 *--pto = *--pfrom;
3093
3094 store_op2 (op, loc, arg1, arg2);
3095 }
3096
3097
3098 /* P points to just after a ^ in PATTERN. Return true if that ^ comes
3099 after an alternative or a begin-subexpression. We assume there is at
3100 least one character before the ^. */
3101
3102 static boolean
3103 at_begline_loc_p (pattern, p, syntax)
3104 const char *pattern, *p;
3105 reg_syntax_t syntax;
3106 {
3107 const char *prev = p - 2;
3108 boolean prev_prev_backslash = prev > pattern && prev[-1] == '\\';
3109
3110 return
3111 /* After a subexpression? */
3112 (*prev == '(' && (syntax & RE_NO_BK_PARENS || prev_prev_backslash))
3113 /* After an alternative? */
3114 || (*prev == '|' && (syntax & RE_NO_BK_VBAR || prev_prev_backslash));
3115 }
3116
3117
3118 /* The dual of at_begline_loc_p. This one is for $. We assume there is
3119 at least one character after the $, i.e., `P < PEND'. */
3120
3121 static boolean
3122 at_endline_loc_p (p, pend, syntax)
3123 const char *p, *pend;
3124 int syntax;
3125 {
3126 const char *next = p;
3127 boolean next_backslash = *next == '\\';
3128 const char *next_next = p + 1 < pend ? p + 1 : 0;
3129
3130 return
3131 /* Before a subexpression? */
3132 (syntax & RE_NO_BK_PARENS ? *next == ')'
3133 : next_backslash && next_next && *next_next == ')')
3134 /* Before an alternative? */
3135 || (syntax & RE_NO_BK_VBAR ? *next == '|'
3136 : next_backslash && next_next && *next_next == '|');
3137 }
3138
3139
3140 /* Returns true if REGNUM is in one of COMPILE_STACK's elements and
3141 false if it's not. */
3142
3143 static boolean
3144 group_in_compile_stack (compile_stack, regnum)
3145 compile_stack_type compile_stack;
3146 regnum_t regnum;
3147 {
3148 int this_element;
3149
3150 for (this_element = compile_stack.avail - 1;
3151 this_element >= 0;
3152 this_element--)
3153 if (compile_stack.stack[this_element].regnum == regnum)
3154 return true;
3155
3156 return false;
3157 }
3158 \f
3159 /* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
3160 BUFP. A fastmap records which of the (1 << BYTEWIDTH) possible
3161 characters can start a string that matches the pattern. This fastmap
3162 is used by re_search to skip quickly over impossible starting points.
3163
3164 The caller must supply the address of a (1 << BYTEWIDTH)-byte data
3165 area as BUFP->fastmap.
3166
3167 We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
3168 the pattern buffer.
3169
3170 Returns 0 if we succeed, -2 if an internal error. */
3171
3172 int
3173 re_compile_fastmap (bufp)
3174 struct re_pattern_buffer *bufp;
3175 {
3176 int i, j, k;
3177 #ifdef MATCH_MAY_ALLOCATE
3178 fail_stack_type fail_stack;
3179 #endif
3180 #ifndef REGEX_MALLOC
3181 char *destination;
3182 #endif
3183 /* We don't push any register information onto the failure stack. */
3184 unsigned num_regs = 0;
3185
3186 register char *fastmap = bufp->fastmap;
3187 unsigned char *pattern = bufp->buffer;
3188 unsigned long size = bufp->used;
3189 unsigned char *p = pattern;
3190 register unsigned char *pend = pattern + size;
3191
3192 /* This holds the pointer to the failure stack, when
3193 it is allocated relocatably. */
3194 fail_stack_elt_t *failure_stack_ptr;
3195
3196 /* Assume that each path through the pattern can be null until
3197 proven otherwise. We set this false at the bottom of switch
3198 statement, to which we get only if a particular path doesn't
3199 match the empty string. */
3200 boolean path_can_be_null = true;
3201
3202 /* We aren't doing a `succeed_n' to begin with. */
3203 boolean succeed_n_p = false;
3204
3205 /* If all elements for base leading-codes in fastmap is set, this
3206 flag is set true. */
3207 boolean match_any_multibyte_characters = false;
3208
3209 /* Maximum code of simple (single byte) character. */
3210 int simple_char_max;
3211
3212 assert (fastmap != NULL && p != NULL);
3213
3214 INIT_FAIL_STACK ();
3215 bzero (fastmap, 1 << BYTEWIDTH); /* Assume nothing's valid. */
3216 bufp->fastmap_accurate = 1; /* It will be when we're done. */
3217 bufp->can_be_null = 0;
3218
3219 while (1)
3220 {
3221 if (p == pend || *p == succeed)
3222 {
3223 /* We have reached the (effective) end of pattern. */
3224 if (!FAIL_STACK_EMPTY ())
3225 {
3226 bufp->can_be_null |= path_can_be_null;
3227
3228 /* Reset for next path. */
3229 path_can_be_null = true;
3230
3231 p = fail_stack.stack[--fail_stack.avail].pointer;
3232
3233 continue;
3234 }
3235 else
3236 break;
3237 }
3238
3239 /* We should never be about to go beyond the end of the pattern. */
3240 assert (p < pend);
3241
3242 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
3243 {
3244
3245 /* I guess the idea here is to simply not bother with a fastmap
3246 if a backreference is used, since it's too hard to figure out
3247 the fastmap for the corresponding group. Setting
3248 `can_be_null' stops `re_search_2' from using the fastmap, so
3249 that is all we do. */
3250 case duplicate:
3251 bufp->can_be_null = 1;
3252 goto done;
3253
3254
3255 /* Following are the cases which match a character. These end
3256 with `break'. */
3257
3258 case exactn:
3259 fastmap[p[1]] = 1;
3260 break;
3261
3262
3263 #ifndef emacs
3264 case charset:
3265 for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
3266 if (p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH)))
3267 fastmap[j] = 1;
3268 break;
3269
3270
3271 case charset_not:
3272 /* Chars beyond end of map must be allowed. */
3273 for (j = *p * BYTEWIDTH; j < (1 << BYTEWIDTH); j++)
3274 fastmap[j] = 1;
3275
3276 for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
3277 if (!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))))
3278 fastmap[j] = 1;
3279 break;
3280
3281
3282 case wordchar:
3283 for (j = 0; j < (1 << BYTEWIDTH); j++)
3284 if (SYNTAX (j) == Sword)
3285 fastmap[j] = 1;
3286 break;
3287
3288
3289 case notwordchar:
3290 for (j = 0; j < (1 << BYTEWIDTH); j++)
3291 if (SYNTAX (j) != Sword)
3292 fastmap[j] = 1;
3293 break;
3294 #else /* emacs */
3295 case charset:
3296 for (j = CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH - 1, p++;
3297 j >= 0; j--)
3298 if (p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH)))
3299 fastmap[j] = 1;
3300
3301 if (CHARSET_RANGE_TABLE_EXISTS_P (&p[-2])
3302 && match_any_multibyte_characters == false)
3303 {
3304 /* Set fastmap[I] 1 where I is a base leading code of each
3305 multibyte character in the range table. */
3306 int c, count;
3307
3308 /* Make P points the range table. */
3309 p += CHARSET_BITMAP_SIZE (&p[-2]);
3310
3311 /* Extract the number of ranges in range table into
3312 COUNT. */
3313 EXTRACT_NUMBER_AND_INCR (count, p);
3314 for (; count > 0; count--, p += 2 * 3) /* XXX */
3315 {
3316 /* Extract the start of each range. */
3317 EXTRACT_CHARACTER (c, p);
3318 j = CHAR_CHARSET (c);
3319 fastmap[CHARSET_LEADING_CODE_BASE (j)] = 1;
3320 }
3321 }
3322 break;
3323
3324
3325 case charset_not:
3326 /* Chars beyond end of bitmap are possible matches.
3327 All the single-byte codes can occur in multibyte buffers.
3328 So any that are not listed in the charset
3329 are possible matches, even in multibyte buffers. */
3330 simple_char_max = (1 << BYTEWIDTH);
3331 for (j = CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH;
3332 j < simple_char_max; j++)
3333 fastmap[j] = 1;
3334
3335 for (j = CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH - 1, p++;
3336 j >= 0; j--)
3337 if (!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))))
3338 fastmap[j] = 1;
3339
3340 if (bufp->multibyte)
3341 /* Any character set can possibly contain a character
3342 which doesn't match the specified set of characters. */
3343 {
3344 set_fastmap_for_multibyte_characters:
3345 if (match_any_multibyte_characters == false)
3346 {
3347 for (j = 0x80; j < 0xA0; j++) /* XXX */
3348 if (BASE_LEADING_CODE_P (j))
3349 fastmap[j] = 1;
3350 match_any_multibyte_characters = true;
3351 }
3352 }
3353 break;
3354
3355
3356 case wordchar:
3357 /* All the single-byte codes can occur in multibyte buffers,
3358 and they may have word syntax. So do consider them. */
3359 simple_char_max = (1 << BYTEWIDTH);
3360 for (j = 0; j < simple_char_max; j++)
3361 if (SYNTAX (j) == Sword)
3362 fastmap[j] = 1;
3363
3364 if (bufp->multibyte)
3365 /* Any character set can possibly contain a character
3366 whose syntax is `Sword'. */
3367 goto set_fastmap_for_multibyte_characters;
3368 break;
3369
3370
3371 case notwordchar:
3372 /* All the single-byte codes can occur in multibyte buffers,
3373 and they may not have word syntax. So do consider them. */
3374 simple_char_max = (1 << BYTEWIDTH);
3375 for (j = 0; j < simple_char_max; j++)
3376 if (SYNTAX (j) != Sword)
3377 fastmap[j] = 1;
3378
3379 if (bufp->multibyte)
3380 /* Any character set can possibly contain a character
3381 whose syntax is not `Sword'. */
3382 goto set_fastmap_for_multibyte_characters;
3383 break;
3384 #endif
3385
3386 case anychar:
3387 {
3388 int fastmap_newline = fastmap['\n'];
3389
3390 /* `.' matches anything, except perhaps newline.
3391 Even in a multibyte buffer, it should match any
3392 conceivable byte value for the fastmap. */
3393 if (bufp->multibyte)
3394 match_any_multibyte_characters = true;
3395
3396 simple_char_max = (1 << BYTEWIDTH);
3397 for (j = 0; j < simple_char_max; j++)
3398 fastmap[j] = 1;
3399
3400 /* ... except perhaps newline. */
3401 if (!(bufp->syntax & RE_DOT_NEWLINE))
3402 fastmap['\n'] = fastmap_newline;
3403
3404 /* Return if we have already set `can_be_null'; if we have,
3405 then the fastmap is irrelevant. Something's wrong here. */
3406 else if (bufp->can_be_null)
3407 goto done;
3408
3409 /* Otherwise, have to check alternative paths. */
3410 break;
3411 }
3412
3413 #ifdef emacs
3414 case wordbound:
3415 case notwordbound:
3416 case wordbeg:
3417 case wordend:
3418 case notsyntaxspec:
3419 case syntaxspec:
3420 /* This match depends on text properties. These end with
3421 aborting optimizations. */
3422 bufp->can_be_null = 1;
3423 goto done;
3424 #if 0
3425 k = *p++;
3426 simple_char_max = bufp->multibyte ? 0x80 : (1 << BYTEWIDTH);
3427 for (j = 0; j < simple_char_max; j++)
3428 if (SYNTAX (j) == (enum syntaxcode) k)
3429 fastmap[j] = 1;
3430
3431 if (bufp->multibyte)
3432 /* Any character set can possibly contain a character
3433 whose syntax is K. */
3434 goto set_fastmap_for_multibyte_characters;
3435 break;
3436
3437 case notsyntaxspec:
3438 k = *p++;
3439 simple_char_max = bufp->multibyte ? 0x80 : (1 << BYTEWIDTH);
3440 for (j = 0; j < simple_char_max; j++)
3441 if (SYNTAX (j) != (enum syntaxcode) k)
3442 fastmap[j] = 1;
3443
3444 if (bufp->multibyte)
3445 /* Any character set can possibly contain a character
3446 whose syntax is not K. */
3447 goto set_fastmap_for_multibyte_characters;
3448 break;
3449 #endif
3450
3451
3452 case categoryspec:
3453 k = *p++;
3454 simple_char_max = (1 << BYTEWIDTH);
3455 for (j = 0; j < simple_char_max; j++)
3456 if (CHAR_HAS_CATEGORY (j, k))
3457 fastmap[j] = 1;
3458
3459 if (bufp->multibyte)
3460 /* Any character set can possibly contain a character
3461 whose category is K. */
3462 goto set_fastmap_for_multibyte_characters;
3463 break;
3464
3465
3466 case notcategoryspec:
3467 k = *p++;
3468 simple_char_max = (1 << BYTEWIDTH);
3469 for (j = 0; j < simple_char_max; j++)
3470 if (!CHAR_HAS_CATEGORY (j, k))
3471 fastmap[j] = 1;
3472
3473 if (bufp->multibyte)
3474 /* Any character set can possibly contain a character
3475 whose category is not K. */
3476 goto set_fastmap_for_multibyte_characters;
3477 break;
3478
3479 /* All cases after this match the empty string. These end with
3480 `continue'. */
3481
3482
3483 case before_dot:
3484 case at_dot:
3485 case after_dot:
3486 continue;
3487 #endif /* emacs */
3488
3489
3490 case no_op:
3491 case begline:
3492 case endline:
3493 case begbuf:
3494 case endbuf:
3495 #ifndef emacs
3496 case wordbound:
3497 case notwordbound:
3498 case wordbeg:
3499 case wordend:
3500 #endif
3501 case push_dummy_failure:
3502 continue;
3503
3504
3505 case jump_n:
3506 case pop_failure_jump:
3507 case maybe_pop_jump:
3508 case jump:
3509 case jump_past_alt:
3510 case dummy_failure_jump:
3511 EXTRACT_NUMBER_AND_INCR (j, p);
3512 p += j;
3513 if (j > 0)
3514 continue;
3515
3516 /* Jump backward implies we just went through the body of a
3517 loop and matched nothing. Opcode jumped to should be
3518 `on_failure_jump' or `succeed_n'. Just treat it like an
3519 ordinary jump. For a * loop, it has pushed its failure
3520 point already; if so, discard that as redundant. */
3521 if ((re_opcode_t) *p != on_failure_jump
3522 && (re_opcode_t) *p != succeed_n)
3523 continue;
3524
3525 p++;
3526 EXTRACT_NUMBER_AND_INCR (j, p);
3527 p += j;
3528
3529 /* If what's on the stack is where we are now, pop it. */
3530 if (!FAIL_STACK_EMPTY ()
3531 && fail_stack.stack[fail_stack.avail - 1].pointer == p)
3532 fail_stack.avail--;
3533
3534 continue;
3535
3536
3537 case on_failure_jump:
3538 case on_failure_keep_string_jump:
3539 handle_on_failure_jump:
3540 EXTRACT_NUMBER_AND_INCR (j, p);
3541
3542 /* For some patterns, e.g., `(a?)?', `p+j' here points to the
3543 end of the pattern. We don't want to push such a point,
3544 since when we restore it above, entering the switch will
3545 increment `p' past the end of the pattern. We don't need
3546 to push such a point since we obviously won't find any more
3547 fastmap entries beyond `pend'. Such a pattern can match
3548 the null string, though. */
3549 if (p + j < pend)
3550 {
3551 if (!PUSH_PATTERN_OP (p + j, fail_stack))
3552 {
3553 RESET_FAIL_STACK ();
3554 return -2;
3555 }
3556 }
3557 else
3558 bufp->can_be_null = 1;
3559
3560 if (succeed_n_p)
3561 {
3562 EXTRACT_NUMBER_AND_INCR (k, p); /* Skip the n. */
3563 succeed_n_p = false;
3564 }
3565
3566 continue;
3567
3568
3569 case succeed_n:
3570 /* Get to the number of times to succeed. */
3571 p += 2;
3572
3573 /* Increment p past the n for when k != 0. */
3574 EXTRACT_NUMBER_AND_INCR (k, p);
3575 if (k == 0)
3576 {
3577 p -= 4;
3578 succeed_n_p = true; /* Spaghetti code alert. */
3579 goto handle_on_failure_jump;
3580 }
3581 continue;
3582
3583
3584 case set_number_at:
3585 p += 4;
3586 continue;
3587
3588
3589 case start_memory:
3590 case stop_memory:
3591 p += 2;
3592 continue;
3593
3594
3595 default:
3596 abort (); /* We have listed all the cases. */
3597 } /* switch *p++ */
3598
3599 /* Getting here means we have found the possible starting
3600 characters for one path of the pattern -- and that the empty
3601 string does not match. We need not follow this path further.
3602 Instead, look at the next alternative (remembered on the
3603 stack), or quit if no more. The test at the top of the loop
3604 does these things. */
3605 path_can_be_null = false;
3606 p = pend;
3607 } /* while p */
3608
3609 /* Set `can_be_null' for the last path (also the first path, if the
3610 pattern is empty). */
3611 bufp->can_be_null |= path_can_be_null;
3612
3613 done:
3614 RESET_FAIL_STACK ();
3615 return 0;
3616 } /* re_compile_fastmap */
3617 \f
3618 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
3619 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
3620 this memory for recording register information. STARTS and ENDS
3621 must be allocated using the malloc library routine, and must each
3622 be at least NUM_REGS * sizeof (regoff_t) bytes long.
3623
3624 If NUM_REGS == 0, then subsequent matches should allocate their own
3625 register data.
3626
3627 Unless this function is called, the first search or match using
3628 PATTERN_BUFFER will allocate its own register data, without
3629 freeing the old data. */
3630
3631 void
3632 re_set_registers (bufp, regs, num_regs, starts, ends)
3633 struct re_pattern_buffer *bufp;
3634 struct re_registers *regs;
3635 unsigned num_regs;
3636 regoff_t *starts, *ends;
3637 {
3638 if (num_regs)
3639 {
3640 bufp->regs_allocated = REGS_REALLOCATE;
3641 regs->num_regs = num_regs;
3642 regs->start = starts;
3643 regs->end = ends;
3644 }
3645 else
3646 {
3647 bufp->regs_allocated = REGS_UNALLOCATED;
3648 regs->num_regs = 0;
3649 regs->start = regs->end = (regoff_t *) 0;
3650 }
3651 }
3652 \f
3653 /* Searching routines. */
3654
3655 /* Like re_search_2, below, but only one string is specified, and
3656 doesn't let you say where to stop matching. */
3657
3658 int
3659 re_search (bufp, string, size, startpos, range, regs)
3660 struct re_pattern_buffer *bufp;
3661 const char *string;
3662 int size, startpos, range;
3663 struct re_registers *regs;
3664 {
3665 return re_search_2 (bufp, NULL, 0, string, size, startpos, range,
3666 regs, size);
3667 }
3668
3669 /* End address of virtual concatenation of string. */
3670 #define STOP_ADDR_VSTRING(P) \
3671 (((P) >= size1 ? string2 + size2 : string1 + size1))
3672
3673 /* Address of POS in the concatenation of virtual string. */
3674 #define POS_ADDR_VSTRING(POS) \
3675 (((POS) >= size1 ? string2 - size1 : string1) + (POS))
3676
3677 /* Using the compiled pattern in BUFP->buffer, first tries to match the
3678 virtual concatenation of STRING1 and STRING2, starting first at index
3679 STARTPOS, then at STARTPOS + 1, and so on.
3680
3681 STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
3682
3683 RANGE is how far to scan while trying to match. RANGE = 0 means try
3684 only at STARTPOS; in general, the last start tried is STARTPOS +
3685 RANGE.
3686
3687 In REGS, return the indices of the virtual concatenation of STRING1
3688 and STRING2 that matched the entire BUFP->buffer and its contained
3689 subexpressions.
3690
3691 Do not consider matching one past the index STOP in the virtual
3692 concatenation of STRING1 and STRING2.
3693
3694 We return either the position in the strings at which the match was
3695 found, -1 if no match, or -2 if error (such as failure
3696 stack overflow). */
3697
3698 int
3699 re_search_2 (bufp, string1, size1, string2, size2, startpos, range, regs, stop)
3700 struct re_pattern_buffer *bufp;
3701 const char *string1, *string2;
3702 int size1, size2;
3703 int startpos;
3704 int range;
3705 struct re_registers *regs;
3706 int stop;
3707 {
3708 int val;
3709 register char *fastmap = bufp->fastmap;
3710 register RE_TRANSLATE_TYPE translate = bufp->translate;
3711 int total_size = size1 + size2;
3712 int endpos = startpos + range;
3713 int anchored_start = 0;
3714
3715 /* Nonzero if we have to concern multibyte character. */
3716 int multibyte = bufp->multibyte;
3717
3718 /* Check for out-of-range STARTPOS. */
3719 if (startpos < 0 || startpos > total_size)
3720 return -1;
3721
3722 /* Fix up RANGE if it might eventually take us outside
3723 the virtual concatenation of STRING1 and STRING2.
3724 Make sure we won't move STARTPOS below 0 or above TOTAL_SIZE. */
3725 if (endpos < 0)
3726 range = 0 - startpos;
3727 else if (endpos > total_size)
3728 range = total_size - startpos;
3729
3730 /* If the search isn't to be a backwards one, don't waste time in a
3731 search for a pattern anchored at beginning of buffer. */
3732 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == begbuf && range > 0)
3733 {
3734 if (startpos > 0)
3735 return -1;
3736 else
3737 range = 0;
3738 }
3739
3740 #ifdef emacs
3741 /* In a forward search for something that starts with \=.
3742 don't keep searching past point. */
3743 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == at_dot && range > 0)
3744 {
3745 range = PT_BYTE - BEGV_BYTE - startpos;
3746 if (range < 0)
3747 return -1;
3748 }
3749 #endif /* emacs */
3750
3751 /* Update the fastmap now if not correct already. */
3752 if (fastmap && !bufp->fastmap_accurate)
3753 if (re_compile_fastmap (bufp) == -2)
3754 return -2;
3755
3756 /* See whether the pattern is anchored. */
3757 if (bufp->buffer[0] == begline)
3758 anchored_start = 1;
3759
3760 #ifdef emacs
3761 gl_state.object = re_match_object;
3762 {
3763 int adjpos = NILP (re_match_object) || BUFFERP (re_match_object);
3764 int charpos = SYNTAX_TABLE_BYTE_TO_CHAR (startpos + adjpos);
3765
3766 SETUP_SYNTAX_TABLE_FOR_OBJECT (re_match_object, charpos, 1);
3767 }
3768 #endif
3769
3770 /* Loop through the string, looking for a place to start matching. */
3771 for (;;)
3772 {
3773 /* If the pattern is anchored,
3774 skip quickly past places we cannot match.
3775 We don't bother to treat startpos == 0 specially
3776 because that case doesn't repeat. */
3777 if (anchored_start && startpos > 0)
3778 {
3779 if (! (bufp->newline_anchor
3780 && ((startpos <= size1 ? string1[startpos - 1]
3781 : string2[startpos - size1 - 1])
3782 == '\n')))
3783 goto advance;
3784 }
3785
3786 /* If a fastmap is supplied, skip quickly over characters that
3787 cannot be the start of a match. If the pattern can match the
3788 null string, however, we don't need to skip characters; we want
3789 the first null string. */
3790 if (fastmap && startpos < total_size && !bufp->can_be_null)
3791 {
3792 register const char *d;
3793 register unsigned int buf_ch;
3794
3795 d = POS_ADDR_VSTRING (startpos);
3796
3797 if (range > 0) /* Searching forwards. */
3798 {
3799 register int lim = 0;
3800 int irange = range;
3801
3802 if (startpos < size1 && startpos + range >= size1)
3803 lim = range - (size1 - startpos);
3804
3805 /* Written out as an if-else to avoid testing `translate'
3806 inside the loop. */
3807 if (RE_TRANSLATE_P (translate))
3808 {
3809 if (multibyte)
3810 while (range > lim)
3811 {
3812 int buf_charlen;
3813
3814 buf_ch = STRING_CHAR_AND_LENGTH (d, range - lim,
3815 buf_charlen);
3816
3817 buf_ch = RE_TRANSLATE (translate, buf_ch);
3818 if (buf_ch >= 0400
3819 || fastmap[buf_ch])
3820 break;
3821
3822 range -= buf_charlen;
3823 d += buf_charlen;
3824 }
3825 else
3826 while (range > lim
3827 && !fastmap[(unsigned char)
3828 RE_TRANSLATE (translate, (unsigned char) *d)])
3829 {
3830 d++;
3831 range--;
3832 }
3833 }
3834 else
3835 while (range > lim && !fastmap[(unsigned char) *d])
3836 {
3837 d++;
3838 range--;
3839 }
3840
3841 startpos += irange - range;
3842 }
3843 else /* Searching backwards. */
3844 {
3845 int room = (size1 == 0 || startpos >= size1
3846 ? size2 + size1 - startpos
3847 : size1 - startpos);
3848
3849 buf_ch = STRING_CHAR (d, room);
3850 if (RE_TRANSLATE_P (translate))
3851 buf_ch = RE_TRANSLATE (translate, buf_ch);
3852
3853 if (! (buf_ch >= 0400
3854 || fastmap[buf_ch]))
3855 goto advance;
3856 }
3857 }
3858
3859 /* If can't match the null string, and that's all we have left, fail. */
3860 if (range >= 0 && startpos == total_size && fastmap
3861 && !bufp->can_be_null)
3862 return -1;
3863
3864 val = re_match_2_internal (bufp, string1, size1, string2, size2,
3865 startpos, regs, stop);
3866 #ifndef REGEX_MALLOC
3867 #ifdef C_ALLOCA
3868 alloca (0);
3869 #endif
3870 #endif
3871
3872 if (val >= 0)
3873 return startpos;
3874
3875 if (val == -2)
3876 return -2;
3877
3878 advance:
3879 if (!range)
3880 break;
3881 else if (range > 0)
3882 {
3883 /* Update STARTPOS to the next character boundary. */
3884 if (multibyte)
3885 {
3886 const unsigned char *p
3887 = (const unsigned char *) POS_ADDR_VSTRING (startpos);
3888 const unsigned char *pend
3889 = (const unsigned char *) STOP_ADDR_VSTRING (startpos);
3890 int len = MULTIBYTE_FORM_LENGTH (p, pend - p);
3891
3892 range -= len;
3893 if (range < 0)
3894 break;
3895 startpos += len;
3896 }
3897 else
3898 {
3899 range--;
3900 startpos++;
3901 }
3902 }
3903 else
3904 {
3905 range++;
3906 startpos--;
3907
3908 /* Update STARTPOS to the previous character boundary. */
3909 if (multibyte)
3910 {
3911 const unsigned char *p
3912 = (const unsigned char *) POS_ADDR_VSTRING (startpos);
3913 int len = 0;
3914
3915 /* Find the head of multibyte form. */
3916 while (!CHAR_HEAD_P (*p))
3917 p--, len++;
3918
3919 /* Adjust it. */
3920 #if 0 /* XXX */
3921 if (MULTIBYTE_FORM_LENGTH (p, len + 1) != (len + 1))
3922 ;
3923 else
3924 #endif
3925 {
3926 range += len;
3927 if (range > 0)
3928 break;
3929
3930 startpos -= len;
3931 }
3932 }
3933 }
3934 }
3935 return -1;
3936 } /* re_search_2 */
3937 \f
3938 /* Declarations and macros for re_match_2. */
3939
3940 static int bcmp_translate ();
3941 static boolean alt_match_null_string_p (),
3942 common_op_match_null_string_p (),
3943 group_match_null_string_p ();
3944
3945 /* This converts PTR, a pointer into one of the search strings `string1'
3946 and `string2' into an offset from the beginning of that string. */
3947 #define POINTER_TO_OFFSET(ptr) \
3948 (FIRST_STRING_P (ptr) \
3949 ? ((regoff_t) ((ptr) - string1)) \
3950 : ((regoff_t) ((ptr) - string2 + size1)))
3951
3952 /* Macros for dealing with the split strings in re_match_2. */
3953
3954 #define MATCHING_IN_FIRST_STRING (dend == end_match_1)
3955
3956 /* Call before fetching a character with *d. This switches over to
3957 string2 if necessary. */
3958 #define PREFETCH() \
3959 while (d == dend) \
3960 { \
3961 /* End of string2 => fail. */ \
3962 if (dend == end_match_2) \
3963 goto fail; \
3964 /* End of string1 => advance to string2. */ \
3965 d = string2; \
3966 dend = end_match_2; \
3967 }
3968
3969
3970 /* Test if at very beginning or at very end of the virtual concatenation
3971 of `string1' and `string2'. If only one string, it's `string2'. */
3972 #define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
3973 #define AT_STRINGS_END(d) ((d) == end2)
3974
3975
3976 /* Test if D points to a character which is word-constituent. We have
3977 two special cases to check for: if past the end of string1, look at
3978 the first character in string2; and if before the beginning of
3979 string2, look at the last character in string1. */
3980 #define WORDCHAR_P(d) \
3981 (SYNTAX ((d) == end1 ? *string2 \
3982 : (d) == string2 - 1 ? *(end1 - 1) : *(d)) \
3983 == Sword)
3984
3985 /* Disabled due to a compiler bug -- see comment at case wordbound */
3986
3987 /* The comment at case wordbound is following one, but we don't use
3988 AT_WORD_BOUNDARY anymore to support multibyte form.
3989
3990 The DEC Alpha C compiler 3.x generates incorrect code for the
3991 test WORDCHAR_P (d - 1) != WORDCHAR_P (d) in the expansion of
3992 AT_WORD_BOUNDARY, so this code is disabled. Expanding the
3993 macro and introducing temporary variables works around the bug. */
3994
3995 #if 0
3996 /* Test if the character before D and the one at D differ with respect
3997 to being word-constituent. */
3998 #define AT_WORD_BOUNDARY(d) \
3999 (AT_STRINGS_BEG (d) || AT_STRINGS_END (d) \
4000 || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
4001 #endif
4002
4003 /* Free everything we malloc. */
4004 #ifdef MATCH_MAY_ALLOCATE
4005 #define FREE_VAR(var) if (var) { REGEX_FREE (var); var = NULL; } else
4006 #define FREE_VARIABLES() \
4007 do { \
4008 REGEX_FREE_STACK (fail_stack.stack); \
4009 FREE_VAR (regstart); \
4010 FREE_VAR (regend); \
4011 FREE_VAR (old_regstart); \
4012 FREE_VAR (old_regend); \
4013 FREE_VAR (best_regstart); \
4014 FREE_VAR (best_regend); \
4015 FREE_VAR (reg_info); \
4016 FREE_VAR (reg_dummy); \
4017 FREE_VAR (reg_info_dummy); \
4018 } while (0)
4019 #else
4020 #define FREE_VARIABLES() ((void)0) /* Do nothing! But inhibit gcc warning. */
4021 #endif /* not MATCH_MAY_ALLOCATE */
4022
4023 /* These values must meet several constraints. They must not be valid
4024 register values; since we have a limit of 255 registers (because
4025 we use only one byte in the pattern for the register number), we can
4026 use numbers larger than 255. They must differ by 1, because of
4027 NUM_FAILURE_ITEMS above. And the value for the lowest register must
4028 be larger than the value for the highest register, so we do not try
4029 to actually save any registers when none are active. */
4030 #define NO_HIGHEST_ACTIVE_REG (1 << BYTEWIDTH)
4031 #define NO_LOWEST_ACTIVE_REG (NO_HIGHEST_ACTIVE_REG + 1)
4032 \f
4033 /* Matching routines. */
4034
4035 #ifndef emacs /* Emacs never uses this. */
4036 /* re_match is like re_match_2 except it takes only a single string. */
4037
4038 int
4039 re_match (bufp, string, size, pos, regs)
4040 struct re_pattern_buffer *bufp;
4041 const char *string;
4042 int size, pos;
4043 struct re_registers *regs;
4044 {
4045 int result = re_match_2_internal (bufp, NULL, 0, string, size,
4046 pos, regs, size);
4047 alloca (0);
4048 return result;
4049 }
4050 #endif /* not emacs */
4051
4052 #ifdef emacs
4053 /* In Emacs, this is the string or buffer in which we
4054 are matching. It is used for looking up syntax properties. */
4055 Lisp_Object re_match_object;
4056 #endif
4057
4058 /* re_match_2 matches the compiled pattern in BUFP against the
4059 the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
4060 and SIZE2, respectively). We start matching at POS, and stop
4061 matching at STOP.
4062
4063 If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
4064 store offsets for the substring each group matched in REGS. See the
4065 documentation for exactly how many groups we fill.
4066
4067 We return -1 if no match, -2 if an internal error (such as the
4068 failure stack overflowing). Otherwise, we return the length of the
4069 matched substring. */
4070
4071 int
4072 re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
4073 struct re_pattern_buffer *bufp;
4074 const char *string1, *string2;
4075 int size1, size2;
4076 int pos;
4077 struct re_registers *regs;
4078 int stop;
4079 {
4080 int result;
4081
4082 #ifdef emacs
4083 int charpos;
4084 int adjpos = NILP (re_match_object) || BUFFERP (re_match_object);
4085 gl_state.object = re_match_object;
4086 charpos = SYNTAX_TABLE_BYTE_TO_CHAR (pos + adjpos);
4087 SETUP_SYNTAX_TABLE_FOR_OBJECT (re_match_object, charpos, 1);
4088 #endif
4089
4090 result = re_match_2_internal (bufp, string1, size1, string2, size2,
4091 pos, regs, stop);
4092 alloca (0);
4093 return result;
4094 }
4095
4096 /* This is a separate function so that we can force an alloca cleanup
4097 afterwards. */
4098 static int
4099 re_match_2_internal (bufp, string1, size1, string2, size2, pos, regs, stop)
4100 struct re_pattern_buffer *bufp;
4101 const char *string1, *string2;
4102 int size1, size2;
4103 int pos;
4104 struct re_registers *regs;
4105 int stop;
4106 {
4107 /* General temporaries. */
4108 int mcnt;
4109 unsigned char *p1;
4110
4111 /* Just past the end of the corresponding string. */
4112 const char *end1, *end2;
4113
4114 /* Pointers into string1 and string2, just past the last characters in
4115 each to consider matching. */
4116 const char *end_match_1, *end_match_2;
4117
4118 /* Where we are in the data, and the end of the current string. */
4119 const char *d, *dend;
4120
4121 /* Where we are in the pattern, and the end of the pattern. */
4122 unsigned char *p = bufp->buffer;
4123 register unsigned char *pend = p + bufp->used;
4124
4125 /* Mark the opcode just after a start_memory, so we can test for an
4126 empty subpattern when we get to the stop_memory. */
4127 unsigned char *just_past_start_mem = 0;
4128
4129 /* We use this to map every character in the string. */
4130 RE_TRANSLATE_TYPE translate = bufp->translate;
4131
4132 /* Nonzero if we have to concern multibyte character. */
4133 int multibyte = bufp->multibyte;
4134
4135 /* Failure point stack. Each place that can handle a failure further
4136 down the line pushes a failure point on this stack. It consists of
4137 restart, regend, and reg_info for all registers corresponding to
4138 the subexpressions we're currently inside, plus the number of such
4139 registers, and, finally, two char *'s. The first char * is where
4140 to resume scanning the pattern; the second one is where to resume
4141 scanning the strings. If the latter is zero, the failure point is
4142 a ``dummy''; if a failure happens and the failure point is a dummy,
4143 it gets discarded and the next next one is tried. */
4144 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
4145 fail_stack_type fail_stack;
4146 #endif
4147 #ifdef DEBUG
4148 static unsigned failure_id = 0;
4149 unsigned nfailure_points_pushed = 0, nfailure_points_popped = 0;
4150 #endif
4151
4152 /* This holds the pointer to the failure stack, when
4153 it is allocated relocatably. */
4154 fail_stack_elt_t *failure_stack_ptr;
4155
4156 /* We fill all the registers internally, independent of what we
4157 return, for use in backreferences. The number here includes
4158 an element for register zero. */
4159 unsigned num_regs = bufp->re_nsub + 1;
4160
4161 /* The currently active registers. */
4162 unsigned lowest_active_reg = NO_LOWEST_ACTIVE_REG;
4163 unsigned highest_active_reg = NO_HIGHEST_ACTIVE_REG;
4164
4165 /* Information on the contents of registers. These are pointers into
4166 the input strings; they record just what was matched (on this
4167 attempt) by a subexpression part of the pattern, that is, the
4168 regnum-th regstart pointer points to where in the pattern we began
4169 matching and the regnum-th regend points to right after where we
4170 stopped matching the regnum-th subexpression. (The zeroth register
4171 keeps track of what the whole pattern matches.) */
4172 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
4173 const char **regstart, **regend;
4174 #endif
4175
4176 /* If a group that's operated upon by a repetition operator fails to
4177 match anything, then the register for its start will need to be
4178 restored because it will have been set to wherever in the string we
4179 are when we last see its open-group operator. Similarly for a
4180 register's end. */
4181 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
4182 const char **old_regstart, **old_regend;
4183 #endif
4184
4185 /* The is_active field of reg_info helps us keep track of which (possibly
4186 nested) subexpressions we are currently in. The matched_something
4187 field of reg_info[reg_num] helps us tell whether or not we have
4188 matched any of the pattern so far this time through the reg_num-th
4189 subexpression. These two fields get reset each time through any
4190 loop their register is in. */
4191 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
4192 register_info_type *reg_info;
4193 #endif
4194
4195 /* The following record the register info as found in the above
4196 variables when we find a match better than any we've seen before.
4197 This happens as we backtrack through the failure points, which in
4198 turn happens only if we have not yet matched the entire string. */
4199 unsigned best_regs_set = false;
4200 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
4201 const char **best_regstart, **best_regend;
4202 #endif
4203
4204 /* Logically, this is `best_regend[0]'. But we don't want to have to
4205 allocate space for that if we're not allocating space for anything
4206 else (see below). Also, we never need info about register 0 for
4207 any of the other register vectors, and it seems rather a kludge to
4208 treat `best_regend' differently than the rest. So we keep track of
4209 the end of the best match so far in a separate variable. We
4210 initialize this to NULL so that when we backtrack the first time
4211 and need to test it, it's not garbage. */
4212 const char *match_end = NULL;
4213
4214 /* This helps SET_REGS_MATCHED avoid doing redundant work. */
4215 int set_regs_matched_done = 0;
4216
4217 /* Used when we pop values we don't care about. */
4218 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
4219 const char **reg_dummy;
4220 register_info_type *reg_info_dummy;
4221 #endif
4222
4223 #ifdef DEBUG
4224 /* Counts the total number of registers pushed. */
4225 unsigned num_regs_pushed = 0;
4226 #endif
4227
4228 DEBUG_PRINT1 ("\n\nEntering re_match_2.\n");
4229
4230 INIT_FAIL_STACK ();
4231
4232 #ifdef MATCH_MAY_ALLOCATE
4233 /* Do not bother to initialize all the register variables if there are
4234 no groups in the pattern, as it takes a fair amount of time. If
4235 there are groups, we include space for register 0 (the whole
4236 pattern), even though we never use it, since it simplifies the
4237 array indexing. We should fix this. */
4238 if (bufp->re_nsub)
4239 {
4240 regstart = REGEX_TALLOC (num_regs, const char *);
4241 regend = REGEX_TALLOC (num_regs, const char *);
4242 old_regstart = REGEX_TALLOC (num_regs, const char *);
4243 old_regend = REGEX_TALLOC (num_regs, const char *);
4244 best_regstart = REGEX_TALLOC (num_regs, const char *);
4245 best_regend = REGEX_TALLOC (num_regs, const char *);
4246 reg_info = REGEX_TALLOC (num_regs, register_info_type);
4247 reg_dummy = REGEX_TALLOC (num_regs, const char *);
4248 reg_info_dummy = REGEX_TALLOC (num_regs, register_info_type);
4249
4250 if (!(regstart && regend && old_regstart && old_regend && reg_info
4251 && best_regstart && best_regend && reg_dummy && reg_info_dummy))
4252 {
4253 FREE_VARIABLES ();
4254 return -2;
4255 }
4256 }
4257 else
4258 {
4259 /* We must initialize all our variables to NULL, so that
4260 `FREE_VARIABLES' doesn't try to free them. */
4261 regstart = regend = old_regstart = old_regend = best_regstart
4262 = best_regend = reg_dummy = NULL;
4263 reg_info = reg_info_dummy = (register_info_type *) NULL;
4264 }
4265 #endif /* MATCH_MAY_ALLOCATE */
4266
4267 /* The starting position is bogus. */
4268 if (pos < 0 || pos > size1 + size2)
4269 {
4270 FREE_VARIABLES ();
4271 return -1;
4272 }
4273
4274 /* Initialize subexpression text positions to -1 to mark ones that no
4275 start_memory/stop_memory has been seen for. Also initialize the
4276 register information struct. */
4277 for (mcnt = 1; mcnt < num_regs; mcnt++)
4278 {
4279 regstart[mcnt] = regend[mcnt]
4280 = old_regstart[mcnt] = old_regend[mcnt] = REG_UNSET_VALUE;
4281
4282 REG_MATCH_NULL_STRING_P (reg_info[mcnt]) = MATCH_NULL_UNSET_VALUE;
4283 IS_ACTIVE (reg_info[mcnt]) = 0;
4284 MATCHED_SOMETHING (reg_info[mcnt]) = 0;
4285 EVER_MATCHED_SOMETHING (reg_info[mcnt]) = 0;
4286 }
4287
4288 /* We move `string1' into `string2' if the latter's empty -- but not if
4289 `string1' is null. */
4290 if (size2 == 0 && string1 != NULL)
4291 {
4292 string2 = string1;
4293 size2 = size1;
4294 string1 = 0;
4295 size1 = 0;
4296 }
4297 end1 = string1 + size1;
4298 end2 = string2 + size2;
4299
4300 /* Compute where to stop matching, within the two strings. */
4301 if (stop <= size1)
4302 {
4303 end_match_1 = string1 + stop;
4304 end_match_2 = string2;
4305 }
4306 else
4307 {
4308 end_match_1 = end1;
4309 end_match_2 = string2 + stop - size1;
4310 }
4311
4312 /* `p' scans through the pattern as `d' scans through the data.
4313 `dend' is the end of the input string that `d' points within. `d'
4314 is advanced into the following input string whenever necessary, but
4315 this happens before fetching; therefore, at the beginning of the
4316 loop, `d' can be pointing at the end of a string, but it cannot
4317 equal `string2'. */
4318 if (size1 > 0 && pos <= size1)
4319 {
4320 d = string1 + pos;
4321 dend = end_match_1;
4322 }
4323 else
4324 {
4325 d = string2 + pos - size1;
4326 dend = end_match_2;
4327 }
4328
4329 DEBUG_PRINT1 ("The compiled pattern is: ");
4330 DEBUG_PRINT_COMPILED_PATTERN (bufp, p, pend);
4331 DEBUG_PRINT1 ("The string to match is: `");
4332 DEBUG_PRINT_DOUBLE_STRING (d, string1, size1, string2, size2);
4333 DEBUG_PRINT1 ("'\n");
4334
4335 /* This loops over pattern commands. It exits by returning from the
4336 function if the match is complete, or it drops through if the match
4337 fails at this starting point in the input data. */
4338 for (;;)
4339 {
4340 DEBUG_PRINT2 ("\n0x%x: ", p);
4341
4342 if (p == pend)
4343 { /* End of pattern means we might have succeeded. */
4344 DEBUG_PRINT1 ("end of pattern ... ");
4345
4346 /* If we haven't matched the entire string, and we want the
4347 longest match, try backtracking. */
4348 if (d != end_match_2)
4349 {
4350 /* 1 if this match ends in the same string (string1 or string2)
4351 as the best previous match. */
4352 boolean same_str_p = (FIRST_STRING_P (match_end)
4353 == MATCHING_IN_FIRST_STRING);
4354 /* 1 if this match is the best seen so far. */
4355 boolean best_match_p;
4356
4357 /* AIX compiler got confused when this was combined
4358 with the previous declaration. */
4359 if (same_str_p)
4360 best_match_p = d > match_end;
4361 else
4362 best_match_p = !MATCHING_IN_FIRST_STRING;
4363
4364 DEBUG_PRINT1 ("backtracking.\n");
4365
4366 if (!FAIL_STACK_EMPTY ())
4367 { /* More failure points to try. */
4368
4369 /* If exceeds best match so far, save it. */
4370 if (!best_regs_set || best_match_p)
4371 {
4372 best_regs_set = true;
4373 match_end = d;
4374
4375 DEBUG_PRINT1 ("\nSAVING match as best so far.\n");
4376
4377 for (mcnt = 1; mcnt < num_regs; mcnt++)
4378 {
4379 best_regstart[mcnt] = regstart[mcnt];
4380 best_regend[mcnt] = regend[mcnt];
4381 }
4382 }
4383 goto fail;
4384 }
4385
4386 /* If no failure points, don't restore garbage. And if
4387 last match is real best match, don't restore second
4388 best one. */
4389 else if (best_regs_set && !best_match_p)
4390 {
4391 restore_best_regs:
4392 /* Restore best match. It may happen that `dend ==
4393 end_match_1' while the restored d is in string2.
4394 For example, the pattern `x.*y.*z' against the
4395 strings `x-' and `y-z-', if the two strings are
4396 not consecutive in memory. */
4397 DEBUG_PRINT1 ("Restoring best registers.\n");
4398
4399 d = match_end;
4400 dend = ((d >= string1 && d <= end1)
4401 ? end_match_1 : end_match_2);
4402
4403 for (mcnt = 1; mcnt < num_regs; mcnt++)
4404 {
4405 regstart[mcnt] = best_regstart[mcnt];
4406 regend[mcnt] = best_regend[mcnt];
4407 }
4408 }
4409 } /* d != end_match_2 */
4410
4411 succeed_label:
4412 DEBUG_PRINT1 ("Accepting match.\n");
4413
4414 /* If caller wants register contents data back, do it. */
4415 if (regs && !bufp->no_sub)
4416 {
4417 /* Have the register data arrays been allocated? */
4418 if (bufp->regs_allocated == REGS_UNALLOCATED)
4419 { /* No. So allocate them with malloc. We need one
4420 extra element beyond `num_regs' for the `-1' marker
4421 GNU code uses. */
4422 regs->num_regs = MAX (RE_NREGS, num_regs + 1);
4423 regs->start = TALLOC (regs->num_regs, regoff_t);
4424 regs->end = TALLOC (regs->num_regs, regoff_t);
4425 if (regs->start == NULL || regs->end == NULL)
4426 {
4427 FREE_VARIABLES ();
4428 return -2;
4429 }
4430 bufp->regs_allocated = REGS_REALLOCATE;
4431 }
4432 else if (bufp->regs_allocated == REGS_REALLOCATE)
4433 { /* Yes. If we need more elements than were already
4434 allocated, reallocate them. If we need fewer, just
4435 leave it alone. */
4436 if (regs->num_regs < num_regs + 1)
4437 {
4438 regs->num_regs = num_regs + 1;
4439 RETALLOC (regs->start, regs->num_regs, regoff_t);
4440 RETALLOC (regs->end, regs->num_regs, regoff_t);
4441 if (regs->start == NULL || regs->end == NULL)
4442 {
4443 FREE_VARIABLES ();
4444 return -2;
4445 }
4446 }
4447 }
4448 else
4449 {
4450 /* These braces fend off a "empty body in an else-statement"
4451 warning under GCC when assert expands to nothing. */
4452 assert (bufp->regs_allocated == REGS_FIXED);
4453 }
4454
4455 /* Convert the pointer data in `regstart' and `regend' to
4456 indices. Register zero has to be set differently,
4457 since we haven't kept track of any info for it. */
4458 if (regs->num_regs > 0)
4459 {
4460 regs->start[0] = pos;
4461 regs->end[0] = (MATCHING_IN_FIRST_STRING
4462 ? ((regoff_t) (d - string1))
4463 : ((regoff_t) (d - string2 + size1)));
4464 }
4465
4466 /* Go through the first `min (num_regs, regs->num_regs)'
4467 registers, since that is all we initialized. */
4468 for (mcnt = 1; mcnt < MIN (num_regs, regs->num_regs); mcnt++)
4469 {
4470 if (REG_UNSET (regstart[mcnt]) || REG_UNSET (regend[mcnt]))
4471 regs->start[mcnt] = regs->end[mcnt] = -1;
4472 else
4473 {
4474 regs->start[mcnt]
4475 = (regoff_t) POINTER_TO_OFFSET (regstart[mcnt]);
4476 regs->end[mcnt]
4477 = (regoff_t) POINTER_TO_OFFSET (regend[mcnt]);
4478 }
4479 }
4480
4481 /* If the regs structure we return has more elements than
4482 were in the pattern, set the extra elements to -1. If
4483 we (re)allocated the registers, this is the case,
4484 because we always allocate enough to have at least one
4485 -1 at the end. */
4486 for (mcnt = num_regs; mcnt < regs->num_regs; mcnt++)
4487 regs->start[mcnt] = regs->end[mcnt] = -1;
4488 } /* regs && !bufp->no_sub */
4489
4490 DEBUG_PRINT4 ("%u failure points pushed, %u popped (%u remain).\n",
4491 nfailure_points_pushed, nfailure_points_popped,
4492 nfailure_points_pushed - nfailure_points_popped);
4493 DEBUG_PRINT2 ("%u registers pushed.\n", num_regs_pushed);
4494
4495 mcnt = d - pos - (MATCHING_IN_FIRST_STRING
4496 ? string1
4497 : string2 - size1);
4498
4499 DEBUG_PRINT2 ("Returning %d from re_match_2.\n", mcnt);
4500
4501 FREE_VARIABLES ();
4502 return mcnt;
4503 }
4504
4505 /* Otherwise match next pattern command. */
4506 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
4507 {
4508 /* Ignore these. Used to ignore the n of succeed_n's which
4509 currently have n == 0. */
4510 case no_op:
4511 DEBUG_PRINT1 ("EXECUTING no_op.\n");
4512 break;
4513
4514 case succeed:
4515 DEBUG_PRINT1 ("EXECUTING succeed.\n");
4516 goto succeed_label;
4517
4518 /* Match the next n pattern characters exactly. The following
4519 byte in the pattern defines n, and the n bytes after that
4520 are the characters to match. */
4521 case exactn:
4522 mcnt = *p++;
4523 DEBUG_PRINT2 ("EXECUTING exactn %d.\n", mcnt);
4524
4525 /* This is written out as an if-else so we don't waste time
4526 testing `translate' inside the loop. */
4527 if (RE_TRANSLATE_P (translate))
4528 {
4529 #ifdef emacs
4530 if (multibyte)
4531 do
4532 {
4533 int pat_charlen, buf_charlen;
4534 unsigned int pat_ch, buf_ch;
4535
4536 PREFETCH ();
4537 pat_ch = STRING_CHAR_AND_LENGTH (p, pend - p, pat_charlen);
4538 buf_ch = STRING_CHAR_AND_LENGTH (d, dend - d, buf_charlen);
4539
4540 if (RE_TRANSLATE (translate, buf_ch)
4541 != pat_ch)
4542 goto fail;
4543
4544 p += pat_charlen;
4545 d += buf_charlen;
4546 mcnt -= pat_charlen;
4547 }
4548 while (mcnt > 0);
4549 else
4550 #endif /* not emacs */
4551 do
4552 {
4553 PREFETCH ();
4554 if ((unsigned char) RE_TRANSLATE (translate, (unsigned char) *d)
4555 != (unsigned char) *p++)
4556 goto fail;
4557 d++;
4558 }
4559 while (--mcnt);
4560 }
4561 else
4562 {
4563 do
4564 {
4565 PREFETCH ();
4566 if (*d++ != (char) *p++) goto fail;
4567 }
4568 while (--mcnt);
4569 }
4570 SET_REGS_MATCHED ();
4571 break;
4572
4573
4574 /* Match any character except possibly a newline or a null. */
4575 case anychar:
4576 {
4577 int buf_charlen;
4578 unsigned int buf_ch;
4579
4580 DEBUG_PRINT1 ("EXECUTING anychar.\n");
4581
4582 PREFETCH ();
4583
4584 #ifdef emacs
4585 if (multibyte)
4586 buf_ch = STRING_CHAR_AND_LENGTH (d, dend - d, buf_charlen);
4587 else
4588 #endif /* not emacs */
4589 {
4590 buf_ch = (unsigned char) *d;
4591 buf_charlen = 1;
4592 }
4593
4594 buf_ch = TRANSLATE (buf_ch);
4595
4596 if ((!(bufp->syntax & RE_DOT_NEWLINE)
4597 && buf_ch == '\n')
4598 || ((bufp->syntax & RE_DOT_NOT_NULL)
4599 && buf_ch == '\000'))
4600 goto fail;
4601
4602 SET_REGS_MATCHED ();
4603 DEBUG_PRINT2 (" Matched `%d'.\n", *d);
4604 d += buf_charlen;
4605 }
4606 break;
4607
4608
4609 case charset:
4610 case charset_not:
4611 {
4612 register unsigned int c;
4613 boolean not = (re_opcode_t) *(p - 1) == charset_not;
4614 int len;
4615
4616 /* Start of actual range_table, or end of bitmap if there is no
4617 range table. */
4618 unsigned char *range_table;
4619
4620 /* Nonzero if there is range table. */
4621 int range_table_exists;
4622
4623 /* Number of ranges of range table. Not in bytes. */
4624 int count;
4625
4626 DEBUG_PRINT2 ("EXECUTING charset%s.\n", not ? "_not" : "");
4627
4628 PREFETCH ();
4629 c = (unsigned char) *d;
4630
4631 range_table = CHARSET_RANGE_TABLE (&p[-1]); /* Past the bitmap. */
4632 range_table_exists = CHARSET_RANGE_TABLE_EXISTS_P (&p[-1]);
4633 if (range_table_exists)
4634 EXTRACT_NUMBER_AND_INCR (count, range_table);
4635 else
4636 count = 0;
4637
4638 if (multibyte && BASE_LEADING_CODE_P (c))
4639 c = STRING_CHAR_AND_LENGTH (d, dend - d, len);
4640
4641 if (SINGLE_BYTE_CHAR_P (c))
4642 { /* Lookup bitmap. */
4643 c = TRANSLATE (c); /* The character to match. */
4644 len = 1;
4645
4646 /* Cast to `unsigned' instead of `unsigned char' in
4647 case the bit list is a full 32 bytes long. */
4648 if (c < (unsigned) (CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH)
4649 && p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4650 not = !not;
4651 }
4652 else if (range_table_exists)
4653 CHARSET_LOOKUP_RANGE_TABLE_RAW (not, c, range_table, count);
4654
4655 p = CHARSET_RANGE_TABLE_END (range_table, count);
4656
4657 if (!not) goto fail;
4658
4659 SET_REGS_MATCHED ();
4660 d += len;
4661 break;
4662 }
4663
4664
4665 /* The beginning of a group is represented by start_memory.
4666 The arguments are the register number in the next byte, and the
4667 number of groups inner to this one in the next. The text
4668 matched within the group is recorded (in the internal
4669 registers data structure) under the register number. */
4670 case start_memory:
4671 DEBUG_PRINT3 ("EXECUTING start_memory %d (%d):\n", *p, p[1]);
4672
4673 /* Find out if this group can match the empty string. */
4674 p1 = p; /* To send to group_match_null_string_p. */
4675
4676 if (REG_MATCH_NULL_STRING_P (reg_info[*p]) == MATCH_NULL_UNSET_VALUE)
4677 REG_MATCH_NULL_STRING_P (reg_info[*p])
4678 = group_match_null_string_p (&p1, pend, reg_info);
4679
4680 /* Save the position in the string where we were the last time
4681 we were at this open-group operator in case the group is
4682 operated upon by a repetition operator, e.g., with `(a*)*b'
4683 against `ab'; then we want to ignore where we are now in
4684 the string in case this attempt to match fails. */
4685 old_regstart[*p] = REG_MATCH_NULL_STRING_P (reg_info[*p])
4686 ? REG_UNSET (regstart[*p]) ? d : regstart[*p]
4687 : regstart[*p];
4688 DEBUG_PRINT2 (" old_regstart: %d\n",
4689 POINTER_TO_OFFSET (old_regstart[*p]));
4690
4691 regstart[*p] = d;
4692 DEBUG_PRINT2 (" regstart: %d\n", POINTER_TO_OFFSET (regstart[*p]));
4693
4694 IS_ACTIVE (reg_info[*p]) = 1;
4695 MATCHED_SOMETHING (reg_info[*p]) = 0;
4696
4697 /* Clear this whenever we change the register activity status. */
4698 set_regs_matched_done = 0;
4699
4700 /* This is the new highest active register. */
4701 highest_active_reg = *p;
4702
4703 /* If nothing was active before, this is the new lowest active
4704 register. */
4705 if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
4706 lowest_active_reg = *p;
4707
4708 /* Move past the register number and inner group count. */
4709 p += 2;
4710 just_past_start_mem = p;
4711
4712 break;
4713
4714
4715 /* The stop_memory opcode represents the end of a group. Its
4716 arguments are the same as start_memory's: the register
4717 number, and the number of inner groups. */
4718 case stop_memory:
4719 DEBUG_PRINT3 ("EXECUTING stop_memory %d (%d):\n", *p, p[1]);
4720
4721 /* We need to save the string position the last time we were at
4722 this close-group operator in case the group is operated
4723 upon by a repetition operator, e.g., with `((a*)*(b*)*)*'
4724 against `aba'; then we want to ignore where we are now in
4725 the string in case this attempt to match fails. */
4726 old_regend[*p] = REG_MATCH_NULL_STRING_P (reg_info[*p])
4727 ? REG_UNSET (regend[*p]) ? d : regend[*p]
4728 : regend[*p];
4729 DEBUG_PRINT2 (" old_regend: %d\n",
4730 POINTER_TO_OFFSET (old_regend[*p]));
4731
4732 regend[*p] = d;
4733 DEBUG_PRINT2 (" regend: %d\n", POINTER_TO_OFFSET (regend[*p]));
4734
4735 /* This register isn't active anymore. */
4736 IS_ACTIVE (reg_info[*p]) = 0;
4737
4738 /* Clear this whenever we change the register activity status. */
4739 set_regs_matched_done = 0;
4740
4741 /* If this was the only register active, nothing is active
4742 anymore. */
4743 if (lowest_active_reg == highest_active_reg)
4744 {
4745 lowest_active_reg = NO_LOWEST_ACTIVE_REG;
4746 highest_active_reg = NO_HIGHEST_ACTIVE_REG;
4747 }
4748 else
4749 { /* We must scan for the new highest active register, since
4750 it isn't necessarily one less than now: consider
4751 (a(b)c(d(e)f)g). When group 3 ends, after the f), the
4752 new highest active register is 1. */
4753 unsigned char r = *p - 1;
4754 while (r > 0 && !IS_ACTIVE (reg_info[r]))
4755 r--;
4756
4757 /* If we end up at register zero, that means that we saved
4758 the registers as the result of an `on_failure_jump', not
4759 a `start_memory', and we jumped to past the innermost
4760 `stop_memory'. For example, in ((.)*) we save
4761 registers 1 and 2 as a result of the *, but when we pop
4762 back to the second ), we are at the stop_memory 1.
4763 Thus, nothing is active. */
4764 if (r == 0)
4765 {
4766 lowest_active_reg = NO_LOWEST_ACTIVE_REG;
4767 highest_active_reg = NO_HIGHEST_ACTIVE_REG;
4768 }
4769 else
4770 highest_active_reg = r;
4771 }
4772
4773 /* If just failed to match something this time around with a
4774 group that's operated on by a repetition operator, try to
4775 force exit from the ``loop'', and restore the register
4776 information for this group that we had before trying this
4777 last match. */
4778 if ((!MATCHED_SOMETHING (reg_info[*p])
4779 || just_past_start_mem == p - 1)
4780 && (p + 2) < pend)
4781 {
4782 boolean is_a_jump_n = false;
4783
4784 p1 = p + 2;
4785 mcnt = 0;
4786 switch ((re_opcode_t) *p1++)
4787 {
4788 case jump_n:
4789 is_a_jump_n = true;
4790 case pop_failure_jump:
4791 case maybe_pop_jump:
4792 case jump:
4793 case dummy_failure_jump:
4794 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4795 if (is_a_jump_n)
4796 p1 += 2;
4797 break;
4798
4799 default:
4800 /* do nothing */ ;
4801 }
4802 p1 += mcnt;
4803
4804 /* If the next operation is a jump backwards in the pattern
4805 to an on_failure_jump right before the start_memory
4806 corresponding to this stop_memory, exit from the loop
4807 by forcing a failure after pushing on the stack the
4808 on_failure_jump's jump in the pattern, and d. */
4809 if (mcnt < 0 && (re_opcode_t) *p1 == on_failure_jump
4810 && (re_opcode_t) p1[3] == start_memory && p1[4] == *p)
4811 {
4812 /* If this group ever matched anything, then restore
4813 what its registers were before trying this last
4814 failed match, e.g., with `(a*)*b' against `ab' for
4815 regstart[1], and, e.g., with `((a*)*(b*)*)*'
4816 against `aba' for regend[3].
4817
4818 Also restore the registers for inner groups for,
4819 e.g., `((a*)(b*))*' against `aba' (register 3 would
4820 otherwise get trashed). */
4821
4822 if (EVER_MATCHED_SOMETHING (reg_info[*p]))
4823 {
4824 unsigned r;
4825
4826 EVER_MATCHED_SOMETHING (reg_info[*p]) = 0;
4827
4828 /* Restore this and inner groups' (if any) registers. */
4829 for (r = *p; r < *p + *(p + 1); r++)
4830 {
4831 regstart[r] = old_regstart[r];
4832
4833 /* xx why this test? */
4834 if (old_regend[r] >= regstart[r])
4835 regend[r] = old_regend[r];
4836 }
4837 }
4838 p1++;
4839 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4840 PUSH_FAILURE_POINT (p1 + mcnt, d, -2);
4841
4842 goto fail;
4843 }
4844 }
4845
4846 /* Move past the register number and the inner group count. */
4847 p += 2;
4848 break;
4849
4850
4851 /* \<digit> has been turned into a `duplicate' command which is
4852 followed by the numeric value of <digit> as the register number. */
4853 case duplicate:
4854 {
4855 register const char *d2, *dend2;
4856 int regno = *p++; /* Get which register to match against. */
4857 DEBUG_PRINT2 ("EXECUTING duplicate %d.\n", regno);
4858
4859 /* Can't back reference a group which we've never matched. */
4860 if (REG_UNSET (regstart[regno]) || REG_UNSET (regend[regno]))
4861 goto fail;
4862
4863 /* Where in input to try to start matching. */
4864 d2 = regstart[regno];
4865
4866 /* Where to stop matching; if both the place to start and
4867 the place to stop matching are in the same string, then
4868 set to the place to stop, otherwise, for now have to use
4869 the end of the first string. */
4870
4871 dend2 = ((FIRST_STRING_P (regstart[regno])
4872 == FIRST_STRING_P (regend[regno]))
4873 ? regend[regno] : end_match_1);
4874 for (;;)
4875 {
4876 /* If necessary, advance to next segment in register
4877 contents. */
4878 while (d2 == dend2)
4879 {
4880 if (dend2 == end_match_2) break;
4881 if (dend2 == regend[regno]) break;
4882
4883 /* End of string1 => advance to string2. */
4884 d2 = string2;
4885 dend2 = regend[regno];
4886 }
4887 /* At end of register contents => success */
4888 if (d2 == dend2) break;
4889
4890 /* If necessary, advance to next segment in data. */
4891 PREFETCH ();
4892
4893 /* How many characters left in this segment to match. */
4894 mcnt = dend - d;
4895
4896 /* Want how many consecutive characters we can match in
4897 one shot, so, if necessary, adjust the count. */
4898 if (mcnt > dend2 - d2)
4899 mcnt = dend2 - d2;
4900
4901 /* Compare that many; failure if mismatch, else move
4902 past them. */
4903 if (RE_TRANSLATE_P (translate)
4904 ? bcmp_translate (d, d2, mcnt, translate)
4905 : bcmp (d, d2, mcnt))
4906 goto fail;
4907 d += mcnt, d2 += mcnt;
4908
4909 /* Do this because we've match some characters. */
4910 SET_REGS_MATCHED ();
4911 }
4912 }
4913 break;
4914
4915
4916 /* begline matches the empty string at the beginning of the string
4917 (unless `not_bol' is set in `bufp'), and, if
4918 `newline_anchor' is set, after newlines. */
4919 case begline:
4920 DEBUG_PRINT1 ("EXECUTING begline.\n");
4921
4922 if (AT_STRINGS_BEG (d))
4923 {
4924 if (!bufp->not_bol) break;
4925 }
4926 else if (d[-1] == '\n' && bufp->newline_anchor)
4927 {
4928 break;
4929 }
4930 /* In all other cases, we fail. */
4931 goto fail;
4932
4933
4934 /* endline is the dual of begline. */
4935 case endline:
4936 DEBUG_PRINT1 ("EXECUTING endline.\n");
4937
4938 if (AT_STRINGS_END (d))
4939 {
4940 if (!bufp->not_eol) break;
4941 }
4942
4943 /* We have to ``prefetch'' the next character. */
4944 else if ((d == end1 ? *string2 : *d) == '\n'
4945 && bufp->newline_anchor)
4946 {
4947 break;
4948 }
4949 goto fail;
4950
4951
4952 /* Match at the very beginning of the data. */
4953 case begbuf:
4954 DEBUG_PRINT1 ("EXECUTING begbuf.\n");
4955 if (AT_STRINGS_BEG (d))
4956 break;
4957 goto fail;
4958
4959
4960 /* Match at the very end of the data. */
4961 case endbuf:
4962 DEBUG_PRINT1 ("EXECUTING endbuf.\n");
4963 if (AT_STRINGS_END (d))
4964 break;
4965 goto fail;
4966
4967
4968 /* on_failure_keep_string_jump is used to optimize `.*\n'. It
4969 pushes NULL as the value for the string on the stack. Then
4970 `pop_failure_point' will keep the current value for the
4971 string, instead of restoring it. To see why, consider
4972 matching `foo\nbar' against `.*\n'. The .* matches the foo;
4973 then the . fails against the \n. But the next thing we want
4974 to do is match the \n against the \n; if we restored the
4975 string value, we would be back at the foo.
4976
4977 Because this is used only in specific cases, we don't need to
4978 check all the things that `on_failure_jump' does, to make
4979 sure the right things get saved on the stack. Hence we don't
4980 share its code. The only reason to push anything on the
4981 stack at all is that otherwise we would have to change
4982 `anychar's code to do something besides goto fail in this
4983 case; that seems worse than this. */
4984 case on_failure_keep_string_jump:
4985 DEBUG_PRINT1 ("EXECUTING on_failure_keep_string_jump");
4986
4987 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4988 DEBUG_PRINT3 (" %d (to 0x%x):\n", mcnt, p + mcnt);
4989
4990 PUSH_FAILURE_POINT (p + mcnt, NULL, -2);
4991 break;
4992
4993
4994 /* Uses of on_failure_jump:
4995
4996 Each alternative starts with an on_failure_jump that points
4997 to the beginning of the next alternative. Each alternative
4998 except the last ends with a jump that in effect jumps past
4999 the rest of the alternatives. (They really jump to the
5000 ending jump of the following alternative, because tensioning
5001 these jumps is a hassle.)
5002
5003 Repeats start with an on_failure_jump that points past both
5004 the repetition text and either the following jump or
5005 pop_failure_jump back to this on_failure_jump. */
5006 case on_failure_jump:
5007 on_failure:
5008 DEBUG_PRINT1 ("EXECUTING on_failure_jump");
5009
5010 #if defined (WINDOWSNT) && defined (emacs)
5011 QUIT;
5012 #endif
5013
5014 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5015 DEBUG_PRINT3 (" %d (to 0x%x)", mcnt, p + mcnt);
5016
5017 /* If this on_failure_jump comes right before a group (i.e.,
5018 the original * applied to a group), save the information
5019 for that group and all inner ones, so that if we fail back
5020 to this point, the group's information will be correct.
5021 For example, in \(a*\)*\1, we need the preceding group,
5022 and in \(zz\(a*\)b*\)\2, we need the inner group. */
5023
5024 /* We can't use `p' to check ahead because we push
5025 a failure point to `p + mcnt' after we do this. */
5026 p1 = p;
5027
5028 /* We need to skip no_op's before we look for the
5029 start_memory in case this on_failure_jump is happening as
5030 the result of a completed succeed_n, as in \(a\)\{1,3\}b\1
5031 against aba. */
5032 while (p1 < pend && (re_opcode_t) *p1 == no_op)
5033 p1++;
5034
5035 if (p1 < pend && (re_opcode_t) *p1 == start_memory)
5036 {
5037 /* We have a new highest active register now. This will
5038 get reset at the start_memory we are about to get to,
5039 but we will have saved all the registers relevant to
5040 this repetition op, as described above. */
5041 highest_active_reg = *(p1 + 1) + *(p1 + 2);
5042 if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
5043 lowest_active_reg = *(p1 + 1);
5044 }
5045
5046 DEBUG_PRINT1 (":\n");
5047 PUSH_FAILURE_POINT (p + mcnt, d, -2);
5048 break;
5049
5050
5051 /* A smart repeat ends with `maybe_pop_jump'.
5052 We change it to either `pop_failure_jump' or `jump'. */
5053 case maybe_pop_jump:
5054 #if defined (WINDOWSNT) && defined (emacs)
5055 QUIT;
5056 #endif
5057 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5058 DEBUG_PRINT2 ("EXECUTING maybe_pop_jump %d.\n", mcnt);
5059 {
5060 register unsigned char *p2 = p;
5061
5062 /* Compare the beginning of the repeat with what in the
5063 pattern follows its end. If we can establish that there
5064 is nothing that they would both match, i.e., that we
5065 would have to backtrack because of (as in, e.g., `a*a')
5066 then we can change to pop_failure_jump, because we'll
5067 never have to backtrack.
5068
5069 This is not true in the case of alternatives: in
5070 `(a|ab)*' we do need to backtrack to the `ab' alternative
5071 (e.g., if the string was `ab'). But instead of trying to
5072 detect that here, the alternative has put on a dummy
5073 failure point which is what we will end up popping. */
5074
5075 /* Skip over open/close-group commands.
5076 If what follows this loop is a ...+ construct,
5077 look at what begins its body, since we will have to
5078 match at least one of that. */
5079 while (1)
5080 {
5081 if (p2 + 2 < pend
5082 && ((re_opcode_t) *p2 == stop_memory
5083 || (re_opcode_t) *p2 == start_memory))
5084 p2 += 3;
5085 else if (p2 + 6 < pend
5086 && (re_opcode_t) *p2 == dummy_failure_jump)
5087 p2 += 6;
5088 else
5089 break;
5090 }
5091
5092 p1 = p + mcnt;
5093 /* p1[0] ... p1[2] are the `on_failure_jump' corresponding
5094 to the `maybe_finalize_jump' of this case. Examine what
5095 follows. */
5096
5097 /* If we're at the end of the pattern, we can change. */
5098 if (p2 == pend)
5099 {
5100 /* Consider what happens when matching ":\(.*\)"
5101 against ":/". I don't really understand this code
5102 yet. */
5103 p[-3] = (unsigned char) pop_failure_jump;
5104 DEBUG_PRINT1
5105 (" End of pattern: change to `pop_failure_jump'.\n");
5106 }
5107
5108 else if ((re_opcode_t) *p2 == exactn
5109 || (bufp->newline_anchor && (re_opcode_t) *p2 == endline))
5110 {
5111 register unsigned int c
5112 = *p2 == (unsigned char) endline ? '\n' : p2[2];
5113
5114 if ((re_opcode_t) p1[3] == exactn)
5115 {
5116 if (!(multibyte /* && (c != '\n') */
5117 && BASE_LEADING_CODE_P (c))
5118 ? c != p1[5]
5119 : (STRING_CHAR (&p2[2], pend - &p2[2])
5120 != STRING_CHAR (&p1[5], pend - &p1[5])))
5121 {
5122 p[-3] = (unsigned char) pop_failure_jump;
5123 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n",
5124 c, p1[5]);
5125 }
5126 }
5127
5128 else if ((re_opcode_t) p1[3] == charset
5129 || (re_opcode_t) p1[3] == charset_not)
5130 {
5131 int not = (re_opcode_t) p1[3] == charset_not;
5132
5133 if (multibyte /* && (c != '\n') */
5134 && BASE_LEADING_CODE_P (c))
5135 c = STRING_CHAR (&p2[2], pend - &p2[2]);
5136
5137 /* Test if C is listed in charset (or charset_not)
5138 at `&p1[3]'. */
5139 if (SINGLE_BYTE_CHAR_P (c))
5140 {
5141 if (c < CHARSET_BITMAP_SIZE (&p1[3]) * BYTEWIDTH
5142 && p1[5 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
5143 not = !not;
5144 }
5145 else if (CHARSET_RANGE_TABLE_EXISTS_P (&p1[3]))
5146 CHARSET_LOOKUP_RANGE_TABLE (not, c, &p1[3]);
5147
5148 /* `not' is equal to 1 if c would match, which means
5149 that we can't change to pop_failure_jump. */
5150 if (!not)
5151 {
5152 p[-3] = (unsigned char) pop_failure_jump;
5153 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
5154 }
5155 }
5156 }
5157 else if ((re_opcode_t) *p2 == charset)
5158 {
5159 if ((re_opcode_t) p1[3] == exactn)
5160 {
5161 register unsigned int c = p1[5];
5162 int not = 0;
5163
5164 if (multibyte && BASE_LEADING_CODE_P (c))
5165 c = STRING_CHAR (&p1[5], pend - &p1[5]);
5166
5167 /* Test if C is listed in charset at `p2'. */
5168 if (SINGLE_BYTE_CHAR_P (c))
5169 {
5170 if (c < CHARSET_BITMAP_SIZE (p2) * BYTEWIDTH
5171 && (p2[2 + c / BYTEWIDTH]
5172 & (1 << (c % BYTEWIDTH))))
5173 not = !not;
5174 }
5175 else if (CHARSET_RANGE_TABLE_EXISTS_P (p2))
5176 CHARSET_LOOKUP_RANGE_TABLE (not, c, p2);
5177
5178 if (!not)
5179 {
5180 p[-3] = (unsigned char) pop_failure_jump;
5181 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
5182 }
5183 }
5184
5185 /* It is hard to list up all the character in charset
5186 P2 if it includes multibyte character. Give up in
5187 such case. */
5188 else if (!multibyte || !CHARSET_RANGE_TABLE_EXISTS_P (p2))
5189 {
5190 /* Now, we are sure that P2 has no range table.
5191 So, for the size of bitmap in P2, `p2[1]' is
5192 enough. But P1 may have range table, so the
5193 size of bitmap table of P1 is extracted by
5194 using macro `CHARSET_BITMAP_SIZE'.
5195
5196 Since we know that all the character listed in
5197 P2 is ASCII, it is enough to test only bitmap
5198 table of P1. */
5199
5200 if ((re_opcode_t) p1[3] == charset_not)
5201 {
5202 int idx;
5203 /* We win if the charset_not inside the loop lists
5204 every character listed in the charset after. */
5205 for (idx = 0; idx < (int) p2[1]; idx++)
5206 if (! (p2[2 + idx] == 0
5207 || (idx < CHARSET_BITMAP_SIZE (&p1[3])
5208 && ((p2[2 + idx] & ~ p1[5 + idx]) == 0))))
5209 break;
5210
5211 if (idx == p2[1])
5212 {
5213 p[-3] = (unsigned char) pop_failure_jump;
5214 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
5215 }
5216 }
5217 else if ((re_opcode_t) p1[3] == charset)
5218 {
5219 int idx;
5220 /* We win if the charset inside the loop
5221 has no overlap with the one after the loop. */
5222 for (idx = 0;
5223 (idx < (int) p2[1]
5224 && idx < CHARSET_BITMAP_SIZE (&p1[3]));
5225 idx++)
5226 if ((p2[2 + idx] & p1[5 + idx]) != 0)
5227 break;
5228
5229 if (idx == p2[1]
5230 || idx == CHARSET_BITMAP_SIZE (&p1[3]))
5231 {
5232 p[-3] = (unsigned char) pop_failure_jump;
5233 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
5234 }
5235 }
5236 }
5237 }
5238 }
5239 p -= 2; /* Point at relative address again. */
5240 if ((re_opcode_t) p[-1] != pop_failure_jump)
5241 {
5242 p[-1] = (unsigned char) jump;
5243 DEBUG_PRINT1 (" Match => jump.\n");
5244 goto unconditional_jump;
5245 }
5246 /* Note fall through. */
5247
5248
5249 /* The end of a simple repeat has a pop_failure_jump back to
5250 its matching on_failure_jump, where the latter will push a
5251 failure point. The pop_failure_jump takes off failure
5252 points put on by this pop_failure_jump's matching
5253 on_failure_jump; we got through the pattern to here from the
5254 matching on_failure_jump, so didn't fail. */
5255 case pop_failure_jump:
5256 {
5257 /* We need to pass separate storage for the lowest and
5258 highest registers, even though we don't care about the
5259 actual values. Otherwise, we will restore only one
5260 register from the stack, since lowest will == highest in
5261 `pop_failure_point'. */
5262 unsigned dummy_low_reg, dummy_high_reg;
5263 unsigned char *pdummy;
5264 const char *sdummy;
5265
5266 DEBUG_PRINT1 ("EXECUTING pop_failure_jump.\n");
5267 POP_FAILURE_POINT (sdummy, pdummy,
5268 dummy_low_reg, dummy_high_reg,
5269 reg_dummy, reg_dummy, reg_info_dummy);
5270 }
5271 /* Note fall through. */
5272
5273
5274 /* Unconditionally jump (without popping any failure points). */
5275 case jump:
5276 unconditional_jump:
5277 #if defined (WINDOWSNT) && defined (emacs)
5278 QUIT;
5279 #endif
5280 EXTRACT_NUMBER_AND_INCR (mcnt, p); /* Get the amount to jump. */
5281 DEBUG_PRINT2 ("EXECUTING jump %d ", mcnt);
5282 p += mcnt; /* Do the jump. */
5283 DEBUG_PRINT2 ("(to 0x%x).\n", p);
5284 break;
5285
5286
5287 /* We need this opcode so we can detect where alternatives end
5288 in `group_match_null_string_p' et al. */
5289 case jump_past_alt:
5290 DEBUG_PRINT1 ("EXECUTING jump_past_alt.\n");
5291 goto unconditional_jump;
5292
5293
5294 /* Normally, the on_failure_jump pushes a failure point, which
5295 then gets popped at pop_failure_jump. We will end up at
5296 pop_failure_jump, also, and with a pattern of, say, `a+', we
5297 are skipping over the on_failure_jump, so we have to push
5298 something meaningless for pop_failure_jump to pop. */
5299 case dummy_failure_jump:
5300 DEBUG_PRINT1 ("EXECUTING dummy_failure_jump.\n");
5301 /* It doesn't matter what we push for the string here. What
5302 the code at `fail' tests is the value for the pattern. */
5303 PUSH_FAILURE_POINT (0, 0, -2);
5304 goto unconditional_jump;
5305
5306
5307 /* At the end of an alternative, we need to push a dummy failure
5308 point in case we are followed by a `pop_failure_jump', because
5309 we don't want the failure point for the alternative to be
5310 popped. For example, matching `(a|ab)*' against `aab'
5311 requires that we match the `ab' alternative. */
5312 case push_dummy_failure:
5313 DEBUG_PRINT1 ("EXECUTING push_dummy_failure.\n");
5314 /* See comments just above at `dummy_failure_jump' about the
5315 two zeroes. */
5316 PUSH_FAILURE_POINT (0, 0, -2);
5317 break;
5318
5319 /* Have to succeed matching what follows at least n times.
5320 After that, handle like `on_failure_jump'. */
5321 case succeed_n:
5322 EXTRACT_NUMBER (mcnt, p + 2);
5323 DEBUG_PRINT2 ("EXECUTING succeed_n %d.\n", mcnt);
5324
5325 assert (mcnt >= 0);
5326 /* Originally, this is how many times we HAVE to succeed. */
5327 if (mcnt > 0)
5328 {
5329 mcnt--;
5330 p += 2;
5331 STORE_NUMBER_AND_INCR (p, mcnt);
5332 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p, mcnt);
5333 }
5334 else if (mcnt == 0)
5335 {
5336 DEBUG_PRINT2 (" Setting two bytes from 0x%x to no_op.\n", p+2);
5337 p[2] = (unsigned char) no_op;
5338 p[3] = (unsigned char) no_op;
5339 goto on_failure;
5340 }
5341 break;
5342
5343 case jump_n:
5344 EXTRACT_NUMBER (mcnt, p + 2);
5345 DEBUG_PRINT2 ("EXECUTING jump_n %d.\n", mcnt);
5346
5347 /* Originally, this is how many times we CAN jump. */
5348 if (mcnt)
5349 {
5350 mcnt--;
5351 STORE_NUMBER (p + 2, mcnt);
5352 goto unconditional_jump;
5353 }
5354 /* If don't have to jump any more, skip over the rest of command. */
5355 else
5356 p += 4;
5357 break;
5358
5359 case set_number_at:
5360 {
5361 DEBUG_PRINT1 ("EXECUTING set_number_at.\n");
5362
5363 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5364 p1 = p + mcnt;
5365 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5366 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p1, mcnt);
5367 STORE_NUMBER (p1, mcnt);
5368 break;
5369 }
5370
5371 case wordbound:
5372 DEBUG_PRINT1 ("EXECUTING wordbound.\n");
5373
5374 /* We SUCCEED in one of the following cases: */
5375
5376 /* Case 1: D is at the beginning or the end of string. */
5377 if (AT_STRINGS_BEG (d) || AT_STRINGS_END (d))
5378 break;
5379 else
5380 {
5381 /* C1 is the character before D, S1 is the syntax of C1, C2
5382 is the character at D, and S2 is the syntax of C2. */
5383 int c1, c2, s1, s2;
5384 int pos1 = PTR_TO_OFFSET (d - 1);
5385 int charpos;
5386
5387 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5388 GET_CHAR_AFTER_2 (c2, d, string1, end1, string2, end2);
5389 #ifdef emacs
5390 charpos = SYNTAX_TABLE_BYTE_TO_CHAR (pos1);
5391 UPDATE_SYNTAX_TABLE (charpos);
5392 #endif
5393 s1 = SYNTAX (c1);
5394 #ifdef emacs
5395 UPDATE_SYNTAX_TABLE_FORWARD (charpos + 1);
5396 #endif
5397 s2 = SYNTAX (c2);
5398
5399 if (/* Case 2: Only one of S1 and S2 is Sword. */
5400 ((s1 == Sword) != (s2 == Sword))
5401 /* Case 3: Both of S1 and S2 are Sword, and macro
5402 WORD_BOUNDARY_P (C1, C2) returns nonzero. */
5403 || ((s1 == Sword) && WORD_BOUNDARY_P (c1, c2)))
5404 break;
5405 }
5406 goto fail;
5407
5408 case notwordbound:
5409 DEBUG_PRINT1 ("EXECUTING notwordbound.\n");
5410
5411 /* We FAIL in one of the following cases: */
5412
5413 /* Case 1: D is at the beginning or the end of string. */
5414 if (AT_STRINGS_BEG (d) || AT_STRINGS_END (d))
5415 goto fail;
5416 else
5417 {
5418 /* C1 is the character before D, S1 is the syntax of C1, C2
5419 is the character at D, and S2 is the syntax of C2. */
5420 int c1, c2, s1, s2;
5421 int pos1 = PTR_TO_OFFSET (d - 1);
5422 int charpos;
5423
5424 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5425 GET_CHAR_AFTER_2 (c2, d, string1, end1, string2, end2);
5426 #ifdef emacs
5427 charpos = SYNTAX_TABLE_BYTE_TO_CHAR (pos1);
5428 UPDATE_SYNTAX_TABLE (charpos);
5429 #endif
5430 s1 = SYNTAX (c1);
5431 #ifdef emacs
5432 UPDATE_SYNTAX_TABLE_FORWARD (charpos + 1);
5433 #endif
5434 s2 = SYNTAX (c2);
5435
5436 if (/* Case 2: Only one of S1 and S2 is Sword. */
5437 ((s1 == Sword) != (s2 == Sword))
5438 /* Case 3: Both of S1 and S2 are Sword, and macro
5439 WORD_BOUNDARY_P (C1, C2) returns nonzero. */
5440 || ((s1 == Sword) && WORD_BOUNDARY_P (c1, c2)))
5441 goto fail;
5442 }
5443 break;
5444
5445 case wordbeg:
5446 DEBUG_PRINT1 ("EXECUTING wordbeg.\n");
5447
5448 /* We FAIL in one of the following cases: */
5449
5450 /* Case 1: D is at the end of string. */
5451 if (AT_STRINGS_END (d))
5452 goto fail;
5453 else
5454 {
5455 /* C1 is the character before D, S1 is the syntax of C1, C2
5456 is the character at D, and S2 is the syntax of C2. */
5457 int c1, c2, s1, s2;
5458 int pos1 = PTR_TO_OFFSET (d);
5459 int charpos;
5460
5461 GET_CHAR_AFTER_2 (c2, d, string1, end1, string2, end2);
5462 #ifdef emacs
5463 charpos = SYNTAX_TABLE_BYTE_TO_CHAR (pos1);
5464 UPDATE_SYNTAX_TABLE (charpos);
5465 #endif
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 int pos1 = PTR_TO_OFFSET (d);
5503 int charpos;
5504
5505 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5506 #ifdef emacs
5507 charpos = SYNTAX_TABLE_BYTE_TO_CHAR (pos1 - 1);
5508 UPDATE_SYNTAX_TABLE (charpos);
5509 #endif
5510 s1 = SYNTAX (c1);
5511
5512 /* Case 2: S1 is not Sword. */
5513 if (s1 != Sword)
5514 goto fail;
5515
5516 /* Case 3: D is not at the end of string ... */
5517 if (!AT_STRINGS_END (d))
5518 {
5519 GET_CHAR_AFTER_2 (c2, d, string1, end1, string2, end2);
5520 #ifdef emacs
5521 UPDATE_SYNTAX_TABLE_FORWARD (charpos);
5522 #endif
5523 s2 = SYNTAX (c2);
5524
5525 /* ... and S2 is Sword, and WORD_BOUNDARY_P (C1, C2)
5526 returns 0. */
5527 if ((s2 == Sword) && !WORD_BOUNDARY_P (c1, c2))
5528 goto fail;
5529 }
5530 }
5531 break;
5532
5533 #ifdef emacs
5534 case before_dot:
5535 DEBUG_PRINT1 ("EXECUTING before_dot.\n");
5536 if (PTR_BYTE_POS ((unsigned char *) d) >= PT_BYTE)
5537 goto fail;
5538 break;
5539
5540 case at_dot:
5541 DEBUG_PRINT1 ("EXECUTING at_dot.\n");
5542 if (PTR_BYTE_POS ((unsigned char *) d) != PT_BYTE)
5543 goto fail;
5544 break;
5545
5546 case after_dot:
5547 DEBUG_PRINT1 ("EXECUTING after_dot.\n");
5548 if (PTR_BYTE_POS ((unsigned char *) d) <= PT_BYTE)
5549 goto fail;
5550 break;
5551
5552 case syntaxspec:
5553 DEBUG_PRINT2 ("EXECUTING syntaxspec %d.\n", mcnt);
5554 mcnt = *p++;
5555 goto matchsyntax;
5556
5557 case wordchar:
5558 DEBUG_PRINT1 ("EXECUTING Emacs wordchar.\n");
5559 mcnt = (int) Sword;
5560 matchsyntax:
5561 PREFETCH ();
5562 #ifdef emacs
5563 {
5564 int pos1 = SYNTAX_TABLE_BYTE_TO_CHAR (PTR_TO_OFFSET (d));
5565 UPDATE_SYNTAX_TABLE (pos1);
5566 }
5567 #endif
5568 {
5569 int c, len;
5570
5571 if (multibyte)
5572 /* we must concern about multibyte form, ... */
5573 c = STRING_CHAR_AND_LENGTH (d, dend - d, len);
5574 else
5575 /* everything should be handled as ASCII, even though it
5576 looks like multibyte form. */
5577 c = *d, len = 1;
5578
5579 if (SYNTAX (c) != (enum syntaxcode) mcnt)
5580 goto fail;
5581 d += len;
5582 }
5583 SET_REGS_MATCHED ();
5584 break;
5585
5586 case notsyntaxspec:
5587 DEBUG_PRINT2 ("EXECUTING notsyntaxspec %d.\n", mcnt);
5588 mcnt = *p++;
5589 goto matchnotsyntax;
5590
5591 case notwordchar:
5592 DEBUG_PRINT1 ("EXECUTING Emacs notwordchar.\n");
5593 mcnt = (int) Sword;
5594 matchnotsyntax:
5595 PREFETCH ();
5596 #ifdef emacs
5597 {
5598 int pos1 = SYNTAX_TABLE_BYTE_TO_CHAR (PTR_TO_OFFSET (d));
5599 UPDATE_SYNTAX_TABLE (pos1);
5600 }
5601 #endif
5602 {
5603 int c, len;
5604
5605 if (multibyte)
5606 c = STRING_CHAR_AND_LENGTH (d, dend - d, len);
5607 else
5608 c = *d, len = 1;
5609
5610 if (SYNTAX (c) == (enum syntaxcode) mcnt)
5611 goto fail;
5612 d += len;
5613 }
5614 SET_REGS_MATCHED ();
5615 break;
5616
5617 case categoryspec:
5618 DEBUG_PRINT2 ("EXECUTING categoryspec %d.\n", *p);
5619 mcnt = *p++;
5620 PREFETCH ();
5621 {
5622 int c, len;
5623
5624 if (multibyte)
5625 c = STRING_CHAR_AND_LENGTH (d, dend - d, len);
5626 else
5627 c = *d, len = 1;
5628
5629 if (!CHAR_HAS_CATEGORY (c, mcnt))
5630 goto fail;
5631 d += len;
5632 }
5633 SET_REGS_MATCHED ();
5634 break;
5635
5636 case notcategoryspec:
5637 DEBUG_PRINT2 ("EXECUTING notcategoryspec %d.\n", *p);
5638 mcnt = *p++;
5639 PREFETCH ();
5640 {
5641 int c, len;
5642
5643 if (multibyte)
5644 c = STRING_CHAR_AND_LENGTH (d, dend - d, len);
5645 else
5646 c = *d, len = 1;
5647
5648 if (CHAR_HAS_CATEGORY (c, mcnt))
5649 goto fail;
5650 d += len;
5651 }
5652 SET_REGS_MATCHED ();
5653 break;
5654
5655 #else /* not emacs */
5656 case wordchar:
5657 DEBUG_PRINT1 ("EXECUTING non-Emacs wordchar.\n");
5658 PREFETCH ();
5659 if (!WORDCHAR_P (d))
5660 goto fail;
5661 SET_REGS_MATCHED ();
5662 d++;
5663 break;
5664
5665 case notwordchar:
5666 DEBUG_PRINT1 ("EXECUTING non-Emacs notwordchar.\n");
5667 PREFETCH ();
5668 if (WORDCHAR_P (d))
5669 goto fail;
5670 SET_REGS_MATCHED ();
5671 d++;
5672 break;
5673 #endif /* not emacs */
5674
5675 default:
5676 abort ();
5677 }
5678 continue; /* Successfully executed one pattern command; keep going. */
5679
5680
5681 /* We goto here if a matching operation fails. */
5682 fail:
5683 #if defined (WINDOWSNT) && defined (emacs)
5684 QUIT;
5685 #endif
5686 if (!FAIL_STACK_EMPTY ())
5687 { /* A restart point is known. Restore to that state. */
5688 DEBUG_PRINT1 ("\nFAIL:\n");
5689 POP_FAILURE_POINT (d, p,
5690 lowest_active_reg, highest_active_reg,
5691 regstart, regend, reg_info);
5692
5693 /* If this failure point is a dummy, try the next one. */
5694 if (!p)
5695 goto fail;
5696
5697 /* If we failed to the end of the pattern, don't examine *p. */
5698 assert (p <= pend);
5699 if (p < pend)
5700 {
5701 boolean is_a_jump_n = false;
5702
5703 /* If failed to a backwards jump that's part of a repetition
5704 loop, need to pop this failure point and use the next one. */
5705 switch ((re_opcode_t) *p)
5706 {
5707 case jump_n:
5708 is_a_jump_n = true;
5709 case maybe_pop_jump:
5710 case pop_failure_jump:
5711 case jump:
5712 p1 = p + 1;
5713 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5714 p1 += mcnt;
5715
5716 if ((is_a_jump_n && (re_opcode_t) *p1 == succeed_n)
5717 || (!is_a_jump_n
5718 && (re_opcode_t) *p1 == on_failure_jump))
5719 goto fail;
5720 break;
5721 default:
5722 /* do nothing */ ;
5723 }
5724 }
5725
5726 if (d >= string1 && d <= end1)
5727 dend = end_match_1;
5728 }
5729 else
5730 break; /* Matching at this starting point really fails. */
5731 } /* for (;;) */
5732
5733 if (best_regs_set)
5734 goto restore_best_regs;
5735
5736 FREE_VARIABLES ();
5737
5738 return -1; /* Failure to match. */
5739 } /* re_match_2 */
5740 \f
5741 /* Subroutine definitions for re_match_2. */
5742
5743
5744 /* We are passed P pointing to a register number after a start_memory.
5745
5746 Return true if the pattern up to the corresponding stop_memory can
5747 match the empty string, and false otherwise.
5748
5749 If we find the matching stop_memory, sets P to point to one past its number.
5750 Otherwise, sets P to an undefined byte less than or equal to END.
5751
5752 We don't handle duplicates properly (yet). */
5753
5754 static boolean
5755 group_match_null_string_p (p, end, reg_info)
5756 unsigned char **p, *end;
5757 register_info_type *reg_info;
5758 {
5759 int mcnt;
5760 /* Point to after the args to the start_memory. */
5761 unsigned char *p1 = *p + 2;
5762
5763 while (p1 < end)
5764 {
5765 /* Skip over opcodes that can match nothing, and return true or
5766 false, as appropriate, when we get to one that can't, or to the
5767 matching stop_memory. */
5768
5769 switch ((re_opcode_t) *p1)
5770 {
5771 /* Could be either a loop or a series of alternatives. */
5772 case on_failure_jump:
5773 p1++;
5774 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5775
5776 /* If the next operation is not a jump backwards in the
5777 pattern. */
5778
5779 if (mcnt >= 0)
5780 {
5781 /* Go through the on_failure_jumps of the alternatives,
5782 seeing if any of the alternatives cannot match nothing.
5783 The last alternative starts with only a jump,
5784 whereas the rest start with on_failure_jump and end
5785 with a jump, e.g., here is the pattern for `a|b|c':
5786
5787 /on_failure_jump/0/6/exactn/1/a/jump_past_alt/0/6
5788 /on_failure_jump/0/6/exactn/1/b/jump_past_alt/0/3
5789 /exactn/1/c
5790
5791 So, we have to first go through the first (n-1)
5792 alternatives and then deal with the last one separately. */
5793
5794
5795 /* Deal with the first (n-1) alternatives, which start
5796 with an on_failure_jump (see above) that jumps to right
5797 past a jump_past_alt. */
5798
5799 while ((re_opcode_t) p1[mcnt-3] == jump_past_alt)
5800 {
5801 /* `mcnt' holds how many bytes long the alternative
5802 is, including the ending `jump_past_alt' and
5803 its number. */
5804
5805 if (!alt_match_null_string_p (p1, p1 + mcnt - 3,
5806 reg_info))
5807 return false;
5808
5809 /* Move to right after this alternative, including the
5810 jump_past_alt. */
5811 p1 += mcnt;
5812
5813 /* Break if it's the beginning of an n-th alternative
5814 that doesn't begin with an on_failure_jump. */
5815 if ((re_opcode_t) *p1 != on_failure_jump)
5816 break;
5817
5818 /* Still have to check that it's not an n-th
5819 alternative that starts with an on_failure_jump. */
5820 p1++;
5821 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5822 if ((re_opcode_t) p1[mcnt-3] != jump_past_alt)
5823 {
5824 /* Get to the beginning of the n-th alternative. */
5825 p1 -= 3;
5826 break;
5827 }
5828 }
5829
5830 /* Deal with the last alternative: go back and get number
5831 of the `jump_past_alt' just before it. `mcnt' contains
5832 the length of the alternative. */
5833 EXTRACT_NUMBER (mcnt, p1 - 2);
5834
5835 if (!alt_match_null_string_p (p1, p1 + mcnt, reg_info))
5836 return false;
5837
5838 p1 += mcnt; /* Get past the n-th alternative. */
5839 } /* if mcnt > 0 */
5840 break;
5841
5842
5843 case stop_memory:
5844 assert (p1[1] == **p);
5845 *p = p1 + 2;
5846 return true;
5847
5848
5849 default:
5850 if (!common_op_match_null_string_p (&p1, end, reg_info))
5851 return false;
5852 }
5853 } /* while p1 < end */
5854
5855 return false;
5856 } /* group_match_null_string_p */
5857
5858
5859 /* Similar to group_match_null_string_p, but doesn't deal with alternatives:
5860 It expects P to be the first byte of a single alternative and END one
5861 byte past the last. The alternative can contain groups. */
5862
5863 static boolean
5864 alt_match_null_string_p (p, end, reg_info)
5865 unsigned char *p, *end;
5866 register_info_type *reg_info;
5867 {
5868 int mcnt;
5869 unsigned char *p1 = p;
5870
5871 while (p1 < end)
5872 {
5873 /* Skip over opcodes that can match nothing, and break when we get
5874 to one that can't. */
5875
5876 switch ((re_opcode_t) *p1)
5877 {
5878 /* It's a loop. */
5879 case on_failure_jump:
5880 p1++;
5881 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5882 p1 += mcnt;
5883 break;
5884
5885 default:
5886 if (!common_op_match_null_string_p (&p1, end, reg_info))
5887 return false;
5888 }
5889 } /* while p1 < end */
5890
5891 return true;
5892 } /* alt_match_null_string_p */
5893
5894
5895 /* Deals with the ops common to group_match_null_string_p and
5896 alt_match_null_string_p.
5897
5898 Sets P to one after the op and its arguments, if any. */
5899
5900 static boolean
5901 common_op_match_null_string_p (p, end, reg_info)
5902 unsigned char **p, *end;
5903 register_info_type *reg_info;
5904 {
5905 int mcnt;
5906 boolean ret;
5907 int reg_no;
5908 unsigned char *p1 = *p;
5909
5910 switch ((re_opcode_t) *p1++)
5911 {
5912 case no_op:
5913 case begline:
5914 case endline:
5915 case begbuf:
5916 case endbuf:
5917 case wordbeg:
5918 case wordend:
5919 case wordbound:
5920 case notwordbound:
5921 #ifdef emacs
5922 case before_dot:
5923 case at_dot:
5924 case after_dot:
5925 #endif
5926 break;
5927
5928 case start_memory:
5929 reg_no = *p1;
5930 assert (reg_no > 0 && reg_no <= MAX_REGNUM);
5931 ret = group_match_null_string_p (&p1, end, reg_info);
5932
5933 /* Have to set this here in case we're checking a group which
5934 contains a group and a back reference to it. */
5935
5936 if (REG_MATCH_NULL_STRING_P (reg_info[reg_no]) == MATCH_NULL_UNSET_VALUE)
5937 REG_MATCH_NULL_STRING_P (reg_info[reg_no]) = ret;
5938
5939 if (!ret)
5940 return false;
5941 break;
5942
5943 /* If this is an optimized succeed_n for zero times, make the jump. */
5944 case jump:
5945 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5946 if (mcnt >= 0)
5947 p1 += mcnt;
5948 else
5949 return false;
5950 break;
5951
5952 case succeed_n:
5953 /* Get to the number of times to succeed. */
5954 p1 += 2;
5955 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5956
5957 if (mcnt == 0)
5958 {
5959 p1 -= 4;
5960 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5961 p1 += mcnt;
5962 }
5963 else
5964 return false;
5965 break;
5966
5967 case duplicate:
5968 if (!REG_MATCH_NULL_STRING_P (reg_info[*p1]))
5969 return false;
5970 break;
5971
5972 case set_number_at:
5973 p1 += 4;
5974
5975 default:
5976 /* All other opcodes mean we cannot match the empty string. */
5977 return false;
5978 }
5979
5980 *p = p1;
5981 return true;
5982 } /* common_op_match_null_string_p */
5983
5984
5985 /* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
5986 bytes; nonzero otherwise. */
5987
5988 static int
5989 bcmp_translate (s1, s2, len, translate)
5990 unsigned char *s1, *s2;
5991 register int len;
5992 RE_TRANSLATE_TYPE translate;
5993 {
5994 register unsigned char *p1 = s1, *p2 = s2;
5995 unsigned char *p1_end = s1 + len;
5996 unsigned char *p2_end = s2 + len;
5997
5998 while (p1 != p1_end && p2 != p2_end)
5999 {
6000 int p1_charlen, p2_charlen;
6001 int p1_ch, p2_ch;
6002
6003 p1_ch = STRING_CHAR_AND_LENGTH (p1, p1_end - p1, p1_charlen);
6004 p2_ch = STRING_CHAR_AND_LENGTH (p2, p2_end - p2, p2_charlen);
6005
6006 if (RE_TRANSLATE (translate, p1_ch)
6007 != RE_TRANSLATE (translate, p2_ch))
6008 return 1;
6009
6010 p1 += p1_charlen, p2 += p2_charlen;
6011 }
6012
6013 if (p1 != p1_end || p2 != p2_end)
6014 return 1;
6015
6016 return 0;
6017 }
6018 \f
6019 /* Entry points for GNU code. */
6020
6021 /* re_compile_pattern is the GNU regular expression compiler: it
6022 compiles PATTERN (of length SIZE) and puts the result in BUFP.
6023 Returns 0 if the pattern was valid, otherwise an error string.
6024
6025 Assumes the `allocated' (and perhaps `buffer') and `translate' fields
6026 are set in BUFP on entry.
6027
6028 We call regex_compile to do the actual compilation. */
6029
6030 const char *
6031 re_compile_pattern (pattern, length, bufp)
6032 const char *pattern;
6033 int length;
6034 struct re_pattern_buffer *bufp;
6035 {
6036 reg_errcode_t ret;
6037
6038 /* GNU code is written to assume at least RE_NREGS registers will be set
6039 (and at least one extra will be -1). */
6040 bufp->regs_allocated = REGS_UNALLOCATED;
6041
6042 /* And GNU code determines whether or not to get register information
6043 by passing null for the REGS argument to re_match, etc., not by
6044 setting no_sub. */
6045 bufp->no_sub = 0;
6046
6047 /* Match anchors at newline. */
6048 bufp->newline_anchor = 1;
6049
6050 ret = regex_compile (pattern, length, re_syntax_options, bufp);
6051
6052 if (!ret)
6053 return NULL;
6054 return gettext (re_error_msgid[(int) ret]);
6055 }
6056 \f
6057 /* Entry points compatible with 4.2 BSD regex library. We don't define
6058 them unless specifically requested. */
6059
6060 #if defined (_REGEX_RE_COMP) || defined (_LIBC)
6061
6062 /* BSD has one and only one pattern buffer. */
6063 static struct re_pattern_buffer re_comp_buf;
6064
6065 char *
6066 #ifdef _LIBC
6067 /* Make these definitions weak in libc, so POSIX programs can redefine
6068 these names if they don't use our functions, and still use
6069 regcomp/regexec below without link errors. */
6070 weak_function
6071 #endif
6072 re_comp (s)
6073 const char *s;
6074 {
6075 reg_errcode_t ret;
6076
6077 if (!s)
6078 {
6079 if (!re_comp_buf.buffer)
6080 return gettext ("No previous regular expression");
6081 return 0;
6082 }
6083
6084 if (!re_comp_buf.buffer)
6085 {
6086 re_comp_buf.buffer = (unsigned char *) malloc (200);
6087 if (re_comp_buf.buffer == NULL)
6088 return gettext (re_error_msgid[(int) REG_ESPACE]);
6089 re_comp_buf.allocated = 200;
6090
6091 re_comp_buf.fastmap = (char *) malloc (1 << BYTEWIDTH);
6092 if (re_comp_buf.fastmap == NULL)
6093 return gettext (re_error_msgid[(int) REG_ESPACE]);
6094 }
6095
6096 /* Since `re_exec' always passes NULL for the `regs' argument, we
6097 don't need to initialize the pattern buffer fields which affect it. */
6098
6099 /* Match anchors at newlines. */
6100 re_comp_buf.newline_anchor = 1;
6101
6102 ret = regex_compile (s, strlen (s), re_syntax_options, &re_comp_buf);
6103
6104 if (!ret)
6105 return NULL;
6106
6107 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6108 return (char *) gettext (re_error_msgid[(int) ret]);
6109 }
6110
6111
6112 int
6113 #ifdef _LIBC
6114 weak_function
6115 #endif
6116 re_exec (s)
6117 const char *s;
6118 {
6119 const int len = strlen (s);
6120 return
6121 0 <= re_search (&re_comp_buf, s, len, 0, len, (struct re_registers *) 0);
6122 }
6123 #endif /* _REGEX_RE_COMP */
6124 \f
6125 /* POSIX.2 functions. Don't define these for Emacs. */
6126
6127 #ifndef emacs
6128
6129 /* regcomp takes a regular expression as a string and compiles it.
6130
6131 PREG is a regex_t *. We do not expect any fields to be initialized,
6132 since POSIX says we shouldn't. Thus, we set
6133
6134 `buffer' to the compiled pattern;
6135 `used' to the length of the compiled pattern;
6136 `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
6137 REG_EXTENDED bit in CFLAGS is set; otherwise, to
6138 RE_SYNTAX_POSIX_BASIC;
6139 `newline_anchor' to REG_NEWLINE being set in CFLAGS;
6140 `fastmap' and `fastmap_accurate' to zero;
6141 `re_nsub' to the number of subexpressions in PATTERN.
6142
6143 PATTERN is the address of the pattern string.
6144
6145 CFLAGS is a series of bits which affect compilation.
6146
6147 If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
6148 use POSIX basic syntax.
6149
6150 If REG_NEWLINE is set, then . and [^...] don't match newline.
6151 Also, regexec will try a match beginning after every newline.
6152
6153 If REG_ICASE is set, then we considers upper- and lowercase
6154 versions of letters to be equivalent when matching.
6155
6156 If REG_NOSUB is set, then when PREG is passed to regexec, that
6157 routine will report only success or failure, and nothing about the
6158 registers.
6159
6160 It returns 0 if it succeeds, nonzero if it doesn't. (See regex.h for
6161 the return codes and their meanings.) */
6162
6163 int
6164 regcomp (preg, pattern, cflags)
6165 regex_t *preg;
6166 const char *pattern;
6167 int cflags;
6168 {
6169 reg_errcode_t ret;
6170 unsigned syntax
6171 = (cflags & REG_EXTENDED) ?
6172 RE_SYNTAX_POSIX_EXTENDED : RE_SYNTAX_POSIX_BASIC;
6173
6174 /* regex_compile will allocate the space for the compiled pattern. */
6175 preg->buffer = 0;
6176 preg->allocated = 0;
6177 preg->used = 0;
6178
6179 /* Don't bother to use a fastmap when searching. This simplifies the
6180 REG_NEWLINE case: if we used a fastmap, we'd have to put all the
6181 characters after newlines into the fastmap. This way, we just try
6182 every character. */
6183 preg->fastmap = 0;
6184
6185 if (cflags & REG_ICASE)
6186 {
6187 unsigned i;
6188
6189 preg->translate
6190 = (RE_TRANSLATE_TYPE) malloc (CHAR_SET_SIZE
6191 * sizeof (*(RE_TRANSLATE_TYPE)0));
6192 if (preg->translate == NULL)
6193 return (int) REG_ESPACE;
6194
6195 /* Map uppercase characters to corresponding lowercase ones. */
6196 for (i = 0; i < CHAR_SET_SIZE; i++)
6197 preg->translate[i] = ISUPPER (i) ? tolower (i) : i;
6198 }
6199 else
6200 preg->translate = NULL;
6201
6202 /* If REG_NEWLINE is set, newlines are treated differently. */
6203 if (cflags & REG_NEWLINE)
6204 { /* REG_NEWLINE implies neither . nor [^...] match newline. */
6205 syntax &= ~RE_DOT_NEWLINE;
6206 syntax |= RE_HAT_LISTS_NOT_NEWLINE;
6207 /* It also changes the matching behavior. */
6208 preg->newline_anchor = 1;
6209 }
6210 else
6211 preg->newline_anchor = 0;
6212
6213 preg->no_sub = !!(cflags & REG_NOSUB);
6214
6215 /* POSIX says a null character in the pattern terminates it, so we
6216 can use strlen here in compiling the pattern. */
6217 ret = regex_compile (pattern, strlen (pattern), syntax, preg);
6218
6219 /* POSIX doesn't distinguish between an unmatched open-group and an
6220 unmatched close-group: both are REG_EPAREN. */
6221 if (ret == REG_ERPAREN) ret = REG_EPAREN;
6222
6223 return (int) ret;
6224 }
6225
6226
6227 /* regexec searches for a given pattern, specified by PREG, in the
6228 string STRING.
6229
6230 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
6231 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
6232 least NMATCH elements, and we set them to the offsets of the
6233 corresponding matched substrings.
6234
6235 EFLAGS specifies `execution flags' which affect matching: if
6236 REG_NOTBOL is set, then ^ does not match at the beginning of the
6237 string; if REG_NOTEOL is set, then $ does not match at the end.
6238
6239 We return 0 if we find a match and REG_NOMATCH if not. */
6240
6241 int
6242 regexec (preg, string, nmatch, pmatch, eflags)
6243 const regex_t *preg;
6244 const char *string;
6245 size_t nmatch;
6246 regmatch_t pmatch[];
6247 int eflags;
6248 {
6249 int ret;
6250 struct re_registers regs;
6251 regex_t private_preg;
6252 int len = strlen (string);
6253 boolean want_reg_info = !preg->no_sub && nmatch > 0;
6254
6255 private_preg = *preg;
6256
6257 private_preg.not_bol = !!(eflags & REG_NOTBOL);
6258 private_preg.not_eol = !!(eflags & REG_NOTEOL);
6259
6260 /* The user has told us exactly how many registers to return
6261 information about, via `nmatch'. We have to pass that on to the
6262 matching routines. */
6263 private_preg.regs_allocated = REGS_FIXED;
6264
6265 if (want_reg_info)
6266 {
6267 regs.num_regs = nmatch;
6268 regs.start = TALLOC (nmatch, regoff_t);
6269 regs.end = TALLOC (nmatch, regoff_t);
6270 if (regs.start == NULL || regs.end == NULL)
6271 return (int) REG_NOMATCH;
6272 }
6273
6274 /* Perform the searching operation. */
6275 ret = re_search (&private_preg, string, len,
6276 /* start: */ 0, /* range: */ len,
6277 want_reg_info ? &regs : (struct re_registers *) 0);
6278
6279 /* Copy the register information to the POSIX structure. */
6280 if (want_reg_info)
6281 {
6282 if (ret >= 0)
6283 {
6284 unsigned r;
6285
6286 for (r = 0; r < nmatch; r++)
6287 {
6288 pmatch[r].rm_so = regs.start[r];
6289 pmatch[r].rm_eo = regs.end[r];
6290 }
6291 }
6292
6293 /* If we needed the temporary register info, free the space now. */
6294 free (regs.start);
6295 free (regs.end);
6296 }
6297
6298 /* We want zero return to mean success, unlike `re_search'. */
6299 return ret >= 0 ? (int) REG_NOERROR : (int) REG_NOMATCH;
6300 }
6301
6302
6303 /* Returns a message corresponding to an error code, ERRCODE, returned
6304 from either regcomp or regexec. We don't use PREG here. */
6305
6306 size_t
6307 regerror (errcode, preg, errbuf, errbuf_size)
6308 int errcode;
6309 const regex_t *preg;
6310 char *errbuf;
6311 size_t errbuf_size;
6312 {
6313 const char *msg;
6314 size_t msg_size;
6315
6316 if (errcode < 0
6317 || errcode >= (sizeof (re_error_msgid) / sizeof (re_error_msgid[0])))
6318 /* Only error codes returned by the rest of the code should be passed
6319 to this routine. If we are given anything else, or if other regex
6320 code generates an invalid error code, then the program has a bug.
6321 Dump core so we can fix it. */
6322 abort ();
6323
6324 msg = gettext (re_error_msgid[errcode]);
6325
6326 msg_size = strlen (msg) + 1; /* Includes the null. */
6327
6328 if (errbuf_size != 0)
6329 {
6330 if (msg_size > errbuf_size)
6331 {
6332 strncpy (errbuf, msg, errbuf_size - 1);
6333 errbuf[errbuf_size - 1] = 0;
6334 }
6335 else
6336 strcpy (errbuf, msg);
6337 }
6338
6339 return msg_size;
6340 }
6341
6342
6343 /* Free dynamically allocated space used by PREG. */
6344
6345 void
6346 regfree (preg)
6347 regex_t *preg;
6348 {
6349 if (preg->buffer != NULL)
6350 free (preg->buffer);
6351 preg->buffer = NULL;
6352
6353 preg->allocated = 0;
6354 preg->used = 0;
6355
6356 if (preg->fastmap != NULL)
6357 free (preg->fastmap);
6358 preg->fastmap = NULL;
6359 preg->fastmap_accurate = 0;
6360
6361 if (preg->translate != NULL)
6362 free (preg->translate);
6363 preg->translate = NULL;
6364 }
6365
6366 #endif /* not emacs */