Fix bug in previous regex.c change, which broke a\{2,}.
[bpt/emacs.git] / src / regex.c
1 /* Extended regular expression matching and search library, version
2 0.12. (Implements POSIX draft P1003.2/D11.2, except for some of the
3 internationalization features.)
4
5 Copyright (C) 1993-2013 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 3, 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, see <http://www.gnu.org/licenses/>. */
19
20 /* TODO:
21 - structure the opcode space into opcode+flag.
22 - merge with glibc's regex.[ch].
23 - replace (succeed_n + jump_n + set_number_at) with something that doesn't
24 need to modify the compiled regexp so that re_match can be reentrant.
25 - get rid of on_failure_jump_smart by doing the optimization in re_comp
26 rather than at run-time, so that re_match can be reentrant.
27 */
28
29 /* AIX requires this to be the first thing in the file. */
30 #if defined _AIX && !defined REGEX_MALLOC
31 #pragma alloca
32 #endif
33
34 /* Ignore some GCC warnings for now. This section should go away
35 once the Emacs and Gnulib regex code is merged. */
36 #if 4 < __GNUC__ + (5 <= __GNUC_MINOR__) || defined __clang__
37 # pragma GCC diagnostic ignored "-Wstrict-overflow"
38 # ifndef emacs
39 # pragma GCC diagnostic ignored "-Wunused-function"
40 # pragma GCC diagnostic ignored "-Wunused-macros"
41 # pragma GCC diagnostic ignored "-Wunused-result"
42 # pragma GCC diagnostic ignored "-Wunused-variable"
43 # endif
44 #endif
45
46 #if 4 < __GNUC__ + (6 <= __GNUC_MINOR__) && ! defined __clang__
47 # pragma GCC diagnostic ignored "-Wunused-but-set-variable"
48 #endif
49
50 #include <config.h>
51
52 #include <stddef.h>
53
54 #ifdef emacs
55 /* We need this for `regex.h', and perhaps for the Emacs include files. */
56 # include <sys/types.h>
57 #endif
58
59 /* Whether to use ISO C Amendment 1 wide char functions.
60 Those should not be used for Emacs since it uses its own. */
61 #if defined _LIBC
62 #define WIDE_CHAR_SUPPORT 1
63 #else
64 #define WIDE_CHAR_SUPPORT \
65 (HAVE_WCTYPE_H && HAVE_WCHAR_H && HAVE_BTOWC && !emacs)
66 #endif
67
68 /* For platform which support the ISO C amendment 1 functionality we
69 support user defined character classes. */
70 #if WIDE_CHAR_SUPPORT
71 /* Solaris 2.5 has a bug: <wchar.h> must be included before <wctype.h>. */
72 # include <wchar.h>
73 # include <wctype.h>
74 #endif
75
76 #ifdef _LIBC
77 /* We have to keep the namespace clean. */
78 # define regfree(preg) __regfree (preg)
79 # define regexec(pr, st, nm, pm, ef) __regexec (pr, st, nm, pm, ef)
80 # define regcomp(preg, pattern, cflags) __regcomp (preg, pattern, cflags)
81 # define regerror(err_code, preg, errbuf, errbuf_size) \
82 __regerror (err_code, preg, errbuf, errbuf_size)
83 # define re_set_registers(bu, re, nu, st, en) \
84 __re_set_registers (bu, re, nu, st, en)
85 # define re_match_2(bufp, string1, size1, string2, size2, pos, regs, stop) \
86 __re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
87 # define re_match(bufp, string, size, pos, regs) \
88 __re_match (bufp, string, size, pos, regs)
89 # define re_search(bufp, string, size, startpos, range, regs) \
90 __re_search (bufp, string, size, startpos, range, regs)
91 # define re_compile_pattern(pattern, length, bufp) \
92 __re_compile_pattern (pattern, length, bufp)
93 # define re_set_syntax(syntax) __re_set_syntax (syntax)
94 # define re_search_2(bufp, st1, s1, st2, s2, startpos, range, regs, stop) \
95 __re_search_2 (bufp, st1, s1, st2, s2, startpos, range, regs, stop)
96 # define re_compile_fastmap(bufp) __re_compile_fastmap (bufp)
97
98 /* Make sure we call libc's function even if the user overrides them. */
99 # define btowc __btowc
100 # define iswctype __iswctype
101 # define wctype __wctype
102
103 # define WEAK_ALIAS(a,b) weak_alias (a, b)
104
105 /* We are also using some library internals. */
106 # include <locale/localeinfo.h>
107 # include <locale/elem-hash.h>
108 # include <langinfo.h>
109 #else
110 # define WEAK_ALIAS(a,b)
111 #endif
112
113 /* This is for other GNU distributions with internationalized messages. */
114 #if HAVE_LIBINTL_H || defined _LIBC
115 # include <libintl.h>
116 #else
117 # define gettext(msgid) (msgid)
118 #endif
119
120 #ifndef gettext_noop
121 /* This define is so xgettext can find the internationalizable
122 strings. */
123 # define gettext_noop(String) String
124 #endif
125
126 /* The `emacs' switch turns on certain matching commands
127 that make sense only in Emacs. */
128 #ifdef emacs
129
130 # include "lisp.h"
131 # include "character.h"
132 # include "buffer.h"
133
134 # include "syntax.h"
135 # include "category.h"
136
137 /* Make syntax table lookup grant data in gl_state. */
138 # define SYNTAX(c) syntax_property (c, 1)
139
140 # ifdef malloc
141 # undef malloc
142 # endif
143 # define malloc xmalloc
144 # ifdef realloc
145 # undef realloc
146 # endif
147 # define realloc xrealloc
148 # ifdef free
149 # undef free
150 # endif
151 # define free xfree
152
153 /* Converts the pointer to the char to BEG-based offset from the start. */
154 # define PTR_TO_OFFSET(d) POS_AS_IN_BUFFER (POINTER_TO_OFFSET (d))
155 # define POS_AS_IN_BUFFER(p) ((p) + (NILP (re_match_object) || BUFFERP (re_match_object)))
156
157 # define RE_MULTIBYTE_P(bufp) ((bufp)->multibyte)
158 # define RE_TARGET_MULTIBYTE_P(bufp) ((bufp)->target_multibyte)
159 # define RE_STRING_CHAR(p, multibyte) \
160 (multibyte ? (STRING_CHAR (p)) : (*(p)))
161 # define RE_STRING_CHAR_AND_LENGTH(p, len, multibyte) \
162 (multibyte ? (STRING_CHAR_AND_LENGTH (p, len)) : ((len) = 1, *(p)))
163
164 # define RE_CHAR_TO_MULTIBYTE(c) UNIBYTE_TO_CHAR (c)
165
166 # define RE_CHAR_TO_UNIBYTE(c) CHAR_TO_BYTE_SAFE (c)
167
168 /* Set C a (possibly converted to multibyte) character before P. P
169 points into a string which is the virtual concatenation of STR1
170 (which ends at END1) or STR2 (which ends at END2). */
171 # define GET_CHAR_BEFORE_2(c, p, str1, end1, str2, end2) \
172 do { \
173 if (target_multibyte) \
174 { \
175 re_char *dtemp = (p) == (str2) ? (end1) : (p); \
176 re_char *dlimit = ((p) > (str2) && (p) <= (end2)) ? (str2) : (str1); \
177 while (dtemp-- > dlimit && !CHAR_HEAD_P (*dtemp)); \
178 c = STRING_CHAR (dtemp); \
179 } \
180 else \
181 { \
182 (c = ((p) == (str2) ? (end1) : (p))[-1]); \
183 (c) = RE_CHAR_TO_MULTIBYTE (c); \
184 } \
185 } while (0)
186
187 /* Set C a (possibly converted to multibyte) character at P, and set
188 LEN to the byte length of that character. */
189 # define GET_CHAR_AFTER(c, p, len) \
190 do { \
191 if (target_multibyte) \
192 (c) = STRING_CHAR_AND_LENGTH (p, len); \
193 else \
194 { \
195 (c) = *p; \
196 len = 1; \
197 (c) = RE_CHAR_TO_MULTIBYTE (c); \
198 } \
199 } while (0)
200
201 #else /* not emacs */
202
203 /* If we are not linking with Emacs proper,
204 we can't use the relocating allocator
205 even if config.h says that we can. */
206 # undef REL_ALLOC
207
208 # include <unistd.h>
209
210 /* When used in Emacs's lib-src, we need xmalloc and xrealloc. */
211
212 static void *
213 xmalloc (size_t size)
214 {
215 void *val = malloc (size);
216 if (!val && size)
217 {
218 write (2, "virtual memory exhausted\n", 25);
219 exit (1);
220 }
221 return val;
222 }
223
224 static void *
225 xrealloc (void *block, size_t size)
226 {
227 void *val;
228 /* We must call malloc explicitly when BLOCK is 0, since some
229 reallocs don't do this. */
230 if (! block)
231 val = malloc (size);
232 else
233 val = realloc (block, size);
234 if (!val && size)
235 {
236 write (2, "virtual memory exhausted\n", 25);
237 exit (1);
238 }
239 return val;
240 }
241
242 # ifdef malloc
243 # undef malloc
244 # endif
245 # define malloc xmalloc
246 # ifdef realloc
247 # undef realloc
248 # endif
249 # define realloc xrealloc
250
251 # include <stdbool.h>
252 # include <string.h>
253
254 /* Define the syntax stuff for \<, \>, etc. */
255
256 /* Sword must be nonzero for the wordchar pattern commands in re_match_2. */
257 enum syntaxcode { Swhitespace = 0, Sword = 1, Ssymbol = 2 };
258
259 /* Dummy macros for non-Emacs environments. */
260 # define MAX_MULTIBYTE_LENGTH 1
261 # define RE_MULTIBYTE_P(x) 0
262 # define RE_TARGET_MULTIBYTE_P(x) 0
263 # define WORD_BOUNDARY_P(c1, c2) (0)
264 # define BYTES_BY_CHAR_HEAD(p) (1)
265 # define PREV_CHAR_BOUNDARY(p, limit) ((p)--)
266 # define STRING_CHAR(p) (*(p))
267 # define RE_STRING_CHAR(p, multibyte) STRING_CHAR (p)
268 # define CHAR_STRING(c, s) (*(s) = (c), 1)
269 # define STRING_CHAR_AND_LENGTH(p, actual_len) ((actual_len) = 1, *(p))
270 # define RE_STRING_CHAR_AND_LENGTH(p, len, multibyte) STRING_CHAR_AND_LENGTH (p, len)
271 # define RE_CHAR_TO_MULTIBYTE(c) (c)
272 # define RE_CHAR_TO_UNIBYTE(c) (c)
273 # define GET_CHAR_BEFORE_2(c, p, str1, end1, str2, end2) \
274 (c = ((p) == (str2) ? *((end1) - 1) : *((p) - 1)))
275 # define GET_CHAR_AFTER(c, p, len) \
276 (c = *p, len = 1)
277 # define CHAR_BYTE8_P(c) (0)
278 # define CHAR_LEADING_CODE(c) (c)
279
280 #endif /* not emacs */
281
282 #ifndef RE_TRANSLATE
283 # define RE_TRANSLATE(TBL, C) ((unsigned char)(TBL)[C])
284 # define RE_TRANSLATE_P(TBL) (TBL)
285 #endif
286 \f
287 /* Get the interface, including the syntax bits. */
288 #include "regex.h"
289
290 /* isalpha etc. are used for the character classes. */
291 #include <ctype.h>
292
293 #ifdef emacs
294
295 /* 1 if C is an ASCII character. */
296 # define IS_REAL_ASCII(c) ((c) < 0200)
297
298 /* 1 if C is a unibyte character. */
299 # define ISUNIBYTE(c) (SINGLE_BYTE_CHAR_P ((c)))
300
301 /* The Emacs definitions should not be directly affected by locales. */
302
303 /* In Emacs, these are only used for single-byte characters. */
304 # define ISDIGIT(c) ((c) >= '0' && (c) <= '9')
305 # define ISCNTRL(c) ((c) < ' ')
306 # define ISXDIGIT(c) (((c) >= '0' && (c) <= '9') \
307 || ((c) >= 'a' && (c) <= 'f') \
308 || ((c) >= 'A' && (c) <= 'F'))
309
310 /* This is only used for single-byte characters. */
311 # define ISBLANK(c) ((c) == ' ' || (c) == '\t')
312
313 /* The rest must handle multibyte characters. */
314
315 # define ISGRAPH(c) (SINGLE_BYTE_CHAR_P (c) \
316 ? (c) > ' ' && !((c) >= 0177 && (c) <= 0237) \
317 : 1)
318
319 # define ISPRINT(c) (SINGLE_BYTE_CHAR_P (c) \
320 ? (c) >= ' ' && !((c) >= 0177 && (c) <= 0237) \
321 : 1)
322
323 # define ISALNUM(c) (IS_REAL_ASCII (c) \
324 ? (((c) >= 'a' && (c) <= 'z') \
325 || ((c) >= 'A' && (c) <= 'Z') \
326 || ((c) >= '0' && (c) <= '9')) \
327 : SYNTAX (c) == Sword)
328
329 # define ISALPHA(c) (IS_REAL_ASCII (c) \
330 ? (((c) >= 'a' && (c) <= 'z') \
331 || ((c) >= 'A' && (c) <= 'Z')) \
332 : SYNTAX (c) == Sword)
333
334 # define ISLOWER(c) lowercasep (c)
335
336 # define ISPUNCT(c) (IS_REAL_ASCII (c) \
337 ? ((c) > ' ' && (c) < 0177 \
338 && !(((c) >= 'a' && (c) <= 'z') \
339 || ((c) >= 'A' && (c) <= 'Z') \
340 || ((c) >= '0' && (c) <= '9'))) \
341 : SYNTAX (c) != Sword)
342
343 # define ISSPACE(c) (SYNTAX (c) == Swhitespace)
344
345 # define ISUPPER(c) uppercasep (c)
346
347 # define ISWORD(c) (SYNTAX (c) == Sword)
348
349 #else /* not emacs */
350
351 /* 1 if C is an ASCII character. */
352 # define IS_REAL_ASCII(c) ((c) < 0200)
353
354 /* This distinction is not meaningful, except in Emacs. */
355 # define ISUNIBYTE(c) 1
356
357 # ifdef isblank
358 # define ISBLANK(c) isblank (c)
359 # else
360 # define ISBLANK(c) ((c) == ' ' || (c) == '\t')
361 # endif
362 # ifdef isgraph
363 # define ISGRAPH(c) isgraph (c)
364 # else
365 # define ISGRAPH(c) (isprint (c) && !isspace (c))
366 # endif
367
368 /* Solaris defines ISPRINT so we must undefine it first. */
369 # undef ISPRINT
370 # define ISPRINT(c) isprint (c)
371 # define ISDIGIT(c) isdigit (c)
372 # define ISALNUM(c) isalnum (c)
373 # define ISALPHA(c) isalpha (c)
374 # define ISCNTRL(c) iscntrl (c)
375 # define ISLOWER(c) islower (c)
376 # define ISPUNCT(c) ispunct (c)
377 # define ISSPACE(c) isspace (c)
378 # define ISUPPER(c) isupper (c)
379 # define ISXDIGIT(c) isxdigit (c)
380
381 # define ISWORD(c) ISALPHA (c)
382
383 # ifdef _tolower
384 # define TOLOWER(c) _tolower (c)
385 # else
386 # define TOLOWER(c) tolower (c)
387 # endif
388
389 /* How many characters in the character set. */
390 # define CHAR_SET_SIZE 256
391
392 # ifdef SYNTAX_TABLE
393
394 extern char *re_syntax_table;
395
396 # else /* not SYNTAX_TABLE */
397
398 static char re_syntax_table[CHAR_SET_SIZE];
399
400 static void
401 init_syntax_once (void)
402 {
403 register int c;
404 static int done = 0;
405
406 if (done)
407 return;
408
409 memset (re_syntax_table, 0, sizeof re_syntax_table);
410
411 for (c = 0; c < CHAR_SET_SIZE; ++c)
412 if (ISALNUM (c))
413 re_syntax_table[c] = Sword;
414
415 re_syntax_table['_'] = Ssymbol;
416
417 done = 1;
418 }
419
420 # endif /* not SYNTAX_TABLE */
421
422 # define SYNTAX(c) re_syntax_table[(c)]
423
424 #endif /* not emacs */
425 \f
426 #define SIGN_EXTEND_CHAR(c) ((signed char) (c))
427 \f
428 /* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we
429 use `alloca' instead of `malloc'. This is because using malloc in
430 re_search* or re_match* could cause memory leaks when C-g is used in
431 Emacs; also, malloc is slower and causes storage fragmentation. On
432 the other hand, malloc is more portable, and easier to debug.
433
434 Because we sometimes use alloca, some routines have to be macros,
435 not functions -- `alloca'-allocated space disappears at the end of the
436 function it is called in. */
437
438 #ifdef REGEX_MALLOC
439
440 # define REGEX_ALLOCATE malloc
441 # define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
442 # define REGEX_FREE free
443
444 #else /* not REGEX_MALLOC */
445
446 /* Emacs already defines alloca, sometimes. */
447 # ifndef alloca
448
449 /* Make alloca work the best possible way. */
450 # ifdef __GNUC__
451 # define alloca __builtin_alloca
452 # else /* not __GNUC__ */
453 # ifdef HAVE_ALLOCA_H
454 # include <alloca.h>
455 # endif /* HAVE_ALLOCA_H */
456 # endif /* not __GNUC__ */
457
458 # endif /* not alloca */
459
460 # define REGEX_ALLOCATE alloca
461
462 /* Assumes a `char *destination' variable. */
463 # define REGEX_REALLOCATE(source, osize, nsize) \
464 (destination = alloca (nsize), \
465 memcpy (destination, source, osize))
466
467 /* No need to do anything to free, after alloca. */
468 # define REGEX_FREE(arg) ((void)0) /* Do nothing! But inhibit gcc warning. */
469
470 #endif /* not REGEX_MALLOC */
471
472 /* Define how to allocate the failure stack. */
473
474 #if defined REL_ALLOC && defined REGEX_MALLOC
475
476 # define REGEX_ALLOCATE_STACK(size) \
477 r_alloc (&failure_stack_ptr, (size))
478 # define REGEX_REALLOCATE_STACK(source, osize, nsize) \
479 r_re_alloc (&failure_stack_ptr, (nsize))
480 # define REGEX_FREE_STACK(ptr) \
481 r_alloc_free (&failure_stack_ptr)
482
483 #else /* not using relocating allocator */
484
485 # ifdef REGEX_MALLOC
486
487 # define REGEX_ALLOCATE_STACK malloc
488 # define REGEX_REALLOCATE_STACK(source, osize, nsize) realloc (source, nsize)
489 # define REGEX_FREE_STACK free
490
491 # else /* not REGEX_MALLOC */
492
493 # define REGEX_ALLOCATE_STACK alloca
494
495 # define REGEX_REALLOCATE_STACK(source, osize, nsize) \
496 REGEX_REALLOCATE (source, osize, nsize)
497 /* No need to explicitly free anything. */
498 # define REGEX_FREE_STACK(arg) ((void)0)
499
500 # endif /* not REGEX_MALLOC */
501 #endif /* not using relocating allocator */
502
503
504 /* True if `size1' is non-NULL and PTR is pointing anywhere inside
505 `string1' or just past its end. This works if PTR is NULL, which is
506 a good thing. */
507 #define FIRST_STRING_P(ptr) \
508 (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
509
510 /* (Re)Allocate N items of type T using malloc, or fail. */
511 #define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
512 #define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
513 #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
514
515 #define BYTEWIDTH 8 /* In bits. */
516
517 #define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
518
519 #undef MAX
520 #undef MIN
521 #define MAX(a, b) ((a) > (b) ? (a) : (b))
522 #define MIN(a, b) ((a) < (b) ? (a) : (b))
523
524 /* Type of source-pattern and string chars. */
525 #ifdef _MSC_VER
526 typedef unsigned char re_char;
527 typedef const re_char const_re_char;
528 #else
529 typedef const unsigned char re_char;
530 typedef re_char const_re_char;
531 #endif
532
533 typedef char boolean;
534
535 static regoff_t re_match_2_internal (struct re_pattern_buffer *bufp,
536 re_char *string1, size_t size1,
537 re_char *string2, size_t size2,
538 ssize_t pos,
539 struct re_registers *regs,
540 ssize_t stop);
541 \f
542 /* These are the command codes that appear in compiled regular
543 expressions. Some opcodes are followed by argument bytes. A
544 command code can specify any interpretation whatsoever for its
545 arguments. Zero bytes may appear in the compiled regular expression. */
546
547 typedef enum
548 {
549 no_op = 0,
550
551 /* Succeed right away--no more backtracking. */
552 succeed,
553
554 /* Followed by one byte giving n, then by n literal bytes. */
555 exactn,
556
557 /* Matches any (more or less) character. */
558 anychar,
559
560 /* Matches any one char belonging to specified set. First
561 following byte is number of bitmap bytes. Then come bytes
562 for a bitmap saying which chars are in. Bits in each byte
563 are ordered low-bit-first. A character is in the set if its
564 bit is 1. A character too large to have a bit in the map is
565 automatically not in the set.
566
567 If the length byte has the 0x80 bit set, then that stuff
568 is followed by a range table:
569 2 bytes of flags for character sets (low 8 bits, high 8 bits)
570 See RANGE_TABLE_WORK_BITS below.
571 2 bytes, the number of pairs that follow (upto 32767)
572 pairs, each 2 multibyte characters,
573 each multibyte character represented as 3 bytes. */
574 charset,
575
576 /* Same parameters as charset, but match any character that is
577 not one of those specified. */
578 charset_not,
579
580 /* Start remembering the text that is matched, for storing in a
581 register. Followed by one byte with the register number, in
582 the range 0 to one less than the pattern buffer's re_nsub
583 field. */
584 start_memory,
585
586 /* Stop remembering the text that is matched and store it in a
587 memory register. Followed by one byte with the register
588 number, in the range 0 to one less than `re_nsub' in the
589 pattern buffer. */
590 stop_memory,
591
592 /* Match a duplicate of something remembered. Followed by one
593 byte containing the register number. */
594 duplicate,
595
596 /* Fail unless at beginning of line. */
597 begline,
598
599 /* Fail unless at end of line. */
600 endline,
601
602 /* Succeeds if at beginning of buffer (if emacs) or at beginning
603 of string to be matched (if not). */
604 begbuf,
605
606 /* Analogously, for end of buffer/string. */
607 endbuf,
608
609 /* Followed by two byte relative address to which to jump. */
610 jump,
611
612 /* Followed by two-byte relative address of place to resume at
613 in case of failure. */
614 on_failure_jump,
615
616 /* Like on_failure_jump, but pushes a placeholder instead of the
617 current string position when executed. */
618 on_failure_keep_string_jump,
619
620 /* Just like `on_failure_jump', except that it checks that we
621 don't get stuck in an infinite loop (matching an empty string
622 indefinitely). */
623 on_failure_jump_loop,
624
625 /* Just like `on_failure_jump_loop', except that it checks for
626 a different kind of loop (the kind that shows up with non-greedy
627 operators). This operation has to be immediately preceded
628 by a `no_op'. */
629 on_failure_jump_nastyloop,
630
631 /* A smart `on_failure_jump' used for greedy * and + operators.
632 It analyzes the loop before which it is put and if the
633 loop does not require backtracking, it changes itself to
634 `on_failure_keep_string_jump' and short-circuits the loop,
635 else it just defaults to changing itself into `on_failure_jump'.
636 It assumes that it is pointing to just past a `jump'. */
637 on_failure_jump_smart,
638
639 /* Followed by two-byte relative address and two-byte number n.
640 After matching N times, jump to the address upon failure.
641 Does not work if N starts at 0: use on_failure_jump_loop
642 instead. */
643 succeed_n,
644
645 /* Followed by two-byte relative address, and two-byte number n.
646 Jump to the address N times, then fail. */
647 jump_n,
648
649 /* Set the following two-byte relative address to the
650 subsequent two-byte number. The address *includes* the two
651 bytes of number. */
652 set_number_at,
653
654 wordbeg, /* Succeeds if at word beginning. */
655 wordend, /* Succeeds if at word end. */
656
657 wordbound, /* Succeeds if at a word boundary. */
658 notwordbound, /* Succeeds if not at a word boundary. */
659
660 symbeg, /* Succeeds if at symbol beginning. */
661 symend, /* Succeeds if at symbol end. */
662
663 /* Matches any character whose syntax is specified. Followed by
664 a byte which contains a syntax code, e.g., Sword. */
665 syntaxspec,
666
667 /* Matches any character whose syntax is not that specified. */
668 notsyntaxspec
669
670 #ifdef emacs
671 ,before_dot, /* Succeeds if before point. */
672 at_dot, /* Succeeds if at point. */
673 after_dot, /* Succeeds if after point. */
674
675 /* Matches any character whose category-set contains the specified
676 category. The operator is followed by a byte which contains a
677 category code (mnemonic ASCII character). */
678 categoryspec,
679
680 /* Matches any character whose category-set does not contain the
681 specified category. The operator is followed by a byte which
682 contains the category code (mnemonic ASCII character). */
683 notcategoryspec
684 #endif /* emacs */
685 } re_opcode_t;
686 \f
687 /* Common operations on the compiled pattern. */
688
689 /* Store NUMBER in two contiguous bytes starting at DESTINATION. */
690
691 #define STORE_NUMBER(destination, number) \
692 do { \
693 (destination)[0] = (number) & 0377; \
694 (destination)[1] = (number) >> 8; \
695 } while (0)
696
697 /* Same as STORE_NUMBER, except increment DESTINATION to
698 the byte after where the number is stored. Therefore, DESTINATION
699 must be an lvalue. */
700
701 #define STORE_NUMBER_AND_INCR(destination, number) \
702 do { \
703 STORE_NUMBER (destination, number); \
704 (destination) += 2; \
705 } while (0)
706
707 /* Put into DESTINATION a number stored in two contiguous bytes starting
708 at SOURCE. */
709
710 #define EXTRACT_NUMBER(destination, source) \
711 ((destination) = extract_number (source))
712
713 static int
714 extract_number (re_char *source)
715 {
716 return (SIGN_EXTEND_CHAR (source[1]) << 8) + source[0];
717 }
718
719 /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
720 SOURCE must be an lvalue. */
721
722 #define EXTRACT_NUMBER_AND_INCR(destination, source) \
723 ((destination) = extract_number_and_incr (&source))
724
725 static int
726 extract_number_and_incr (re_char **source)
727 {
728 int num = extract_number (*source);
729 *source += 2;
730 return num;
731 }
732 \f
733 /* Store a multibyte character in three contiguous bytes starting
734 DESTINATION, and increment DESTINATION to the byte after where the
735 character is stored. Therefore, DESTINATION must be an lvalue. */
736
737 #define STORE_CHARACTER_AND_INCR(destination, character) \
738 do { \
739 (destination)[0] = (character) & 0377; \
740 (destination)[1] = ((character) >> 8) & 0377; \
741 (destination)[2] = (character) >> 16; \
742 (destination) += 3; \
743 } while (0)
744
745 /* Put into DESTINATION a character stored in three contiguous bytes
746 starting at SOURCE. */
747
748 #define EXTRACT_CHARACTER(destination, source) \
749 do { \
750 (destination) = ((source)[0] \
751 | ((source)[1] << 8) \
752 | ((source)[2] << 16)); \
753 } while (0)
754
755
756 /* Macros for charset. */
757
758 /* Size of bitmap of charset P in bytes. P is a start of charset,
759 i.e. *P is (re_opcode_t) charset or (re_opcode_t) charset_not. */
760 #define CHARSET_BITMAP_SIZE(p) ((p)[1] & 0x7F)
761
762 /* Nonzero if charset P has range table. */
763 #define CHARSET_RANGE_TABLE_EXISTS_P(p) ((p)[1] & 0x80)
764
765 /* Return the address of range table of charset P. But not the start
766 of table itself, but the before where the number of ranges is
767 stored. `2 +' means to skip re_opcode_t and size of bitmap,
768 and the 2 bytes of flags at the start of the range table. */
769 #define CHARSET_RANGE_TABLE(p) (&(p)[4 + CHARSET_BITMAP_SIZE (p)])
770
771 #ifdef emacs
772 /* Extract the bit flags that start a range table. */
773 #define CHARSET_RANGE_TABLE_BITS(p) \
774 ((p)[2 + CHARSET_BITMAP_SIZE (p)] \
775 + (p)[3 + CHARSET_BITMAP_SIZE (p)] * 0x100)
776 #endif
777
778 /* Return the address of end of RANGE_TABLE. COUNT is number of
779 ranges (which is a pair of (start, end)) in the RANGE_TABLE. `* 2'
780 is start of range and end of range. `* 3' is size of each start
781 and end. */
782 #define CHARSET_RANGE_TABLE_END(range_table, count) \
783 ((range_table) + (count) * 2 * 3)
784
785 /* Test if C is in RANGE_TABLE. A flag NOT is negated if C is in.
786 COUNT is number of ranges in RANGE_TABLE. */
787 #define CHARSET_LOOKUP_RANGE_TABLE_RAW(not, c, range_table, count) \
788 do \
789 { \
790 re_wchar_t range_start, range_end; \
791 re_char *rtp; \
792 re_char *range_table_end \
793 = CHARSET_RANGE_TABLE_END ((range_table), (count)); \
794 \
795 for (rtp = (range_table); rtp < range_table_end; rtp += 2 * 3) \
796 { \
797 EXTRACT_CHARACTER (range_start, rtp); \
798 EXTRACT_CHARACTER (range_end, rtp + 3); \
799 \
800 if (range_start <= (c) && (c) <= range_end) \
801 { \
802 (not) = !(not); \
803 break; \
804 } \
805 } \
806 } \
807 while (0)
808
809 /* Test if C is in range table of CHARSET. The flag NOT is negated if
810 C is listed in it. */
811 #define CHARSET_LOOKUP_RANGE_TABLE(not, c, charset) \
812 do \
813 { \
814 /* Number of ranges in range table. */ \
815 int count; \
816 re_char *range_table = CHARSET_RANGE_TABLE (charset); \
817 \
818 EXTRACT_NUMBER_AND_INCR (count, range_table); \
819 CHARSET_LOOKUP_RANGE_TABLE_RAW ((not), (c), range_table, count); \
820 } \
821 while (0)
822 \f
823 /* If DEBUG is defined, Regex prints many voluminous messages about what
824 it is doing (if the variable `debug' is nonzero). If linked with the
825 main program in `iregex.c', you can enter patterns and strings
826 interactively. And if linked with the main program in `main.c' and
827 the other test files, you can run the already-written tests. */
828
829 #ifdef DEBUG
830
831 /* We use standard I/O for debugging. */
832 # include <stdio.h>
833
834 /* It is useful to test things that ``must'' be true when debugging. */
835 # include <assert.h>
836
837 static int debug = -100000;
838
839 # define DEBUG_STATEMENT(e) e
840 # define DEBUG_PRINT(...) if (debug > 0) printf (__VA_ARGS__)
841 # define DEBUG_COMPILES_ARGUMENTS
842 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) \
843 if (debug > 0) print_partial_compiled_pattern (s, e)
844 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) \
845 if (debug > 0) print_double_string (w, s1, sz1, s2, sz2)
846
847
848 /* Print the fastmap in human-readable form. */
849
850 static void
851 print_fastmap (char *fastmap)
852 {
853 unsigned was_a_range = 0;
854 unsigned i = 0;
855
856 while (i < (1 << BYTEWIDTH))
857 {
858 if (fastmap[i++])
859 {
860 was_a_range = 0;
861 putchar (i - 1);
862 while (i < (1 << BYTEWIDTH) && fastmap[i])
863 {
864 was_a_range = 1;
865 i++;
866 }
867 if (was_a_range)
868 {
869 printf ("-");
870 putchar (i - 1);
871 }
872 }
873 }
874 putchar ('\n');
875 }
876
877
878 /* Print a compiled pattern string in human-readable form, starting at
879 the START pointer into it and ending just before the pointer END. */
880
881 static void
882 print_partial_compiled_pattern (re_char *start, re_char *end)
883 {
884 int mcnt, mcnt2;
885 re_char *p = start;
886 re_char *pend = end;
887
888 if (start == NULL)
889 {
890 fprintf (stderr, "(null)\n");
891 return;
892 }
893
894 /* Loop over pattern commands. */
895 while (p < pend)
896 {
897 fprintf (stderr, "%td:\t", p - start);
898
899 switch ((re_opcode_t) *p++)
900 {
901 case no_op:
902 fprintf (stderr, "/no_op");
903 break;
904
905 case succeed:
906 fprintf (stderr, "/succeed");
907 break;
908
909 case exactn:
910 mcnt = *p++;
911 fprintf (stderr, "/exactn/%d", mcnt);
912 do
913 {
914 fprintf (stderr, "/%c", *p++);
915 }
916 while (--mcnt);
917 break;
918
919 case start_memory:
920 fprintf (stderr, "/start_memory/%d", *p++);
921 break;
922
923 case stop_memory:
924 fprintf (stderr, "/stop_memory/%d", *p++);
925 break;
926
927 case duplicate:
928 fprintf (stderr, "/duplicate/%d", *p++);
929 break;
930
931 case anychar:
932 fprintf (stderr, "/anychar");
933 break;
934
935 case charset:
936 case charset_not:
937 {
938 register int c, last = -100;
939 register int in_range = 0;
940 int length = CHARSET_BITMAP_SIZE (p - 1);
941 int has_range_table = CHARSET_RANGE_TABLE_EXISTS_P (p - 1);
942
943 fprintf (stderr, "/charset [%s",
944 (re_opcode_t) *(p - 1) == charset_not ? "^" : "");
945
946 if (p + *p >= pend)
947 fprintf (stderr, " !extends past end of pattern! ");
948
949 for (c = 0; c < 256; c++)
950 if (c / 8 < length
951 && (p[1 + (c/8)] & (1 << (c % 8))))
952 {
953 /* Are we starting a range? */
954 if (last + 1 == c && ! in_range)
955 {
956 fprintf (stderr, "-");
957 in_range = 1;
958 }
959 /* Have we broken a range? */
960 else if (last + 1 != c && in_range)
961 {
962 fprintf (stderr, "%c", last);
963 in_range = 0;
964 }
965
966 if (! in_range)
967 fprintf (stderr, "%c", c);
968
969 last = c;
970 }
971
972 if (in_range)
973 fprintf (stderr, "%c", last);
974
975 fprintf (stderr, "]");
976
977 p += 1 + length;
978
979 if (has_range_table)
980 {
981 int count;
982 fprintf (stderr, "has-range-table");
983
984 /* ??? Should print the range table; for now, just skip it. */
985 p += 2; /* skip range table bits */
986 EXTRACT_NUMBER_AND_INCR (count, p);
987 p = CHARSET_RANGE_TABLE_END (p, count);
988 }
989 }
990 break;
991
992 case begline:
993 fprintf (stderr, "/begline");
994 break;
995
996 case endline:
997 fprintf (stderr, "/endline");
998 break;
999
1000 case on_failure_jump:
1001 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1002 fprintf (stderr, "/on_failure_jump to %td", p + mcnt - start);
1003 break;
1004
1005 case on_failure_keep_string_jump:
1006 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1007 fprintf (stderr, "/on_failure_keep_string_jump to %td",
1008 p + mcnt - start);
1009 break;
1010
1011 case on_failure_jump_nastyloop:
1012 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1013 fprintf (stderr, "/on_failure_jump_nastyloop to %td",
1014 p + mcnt - start);
1015 break;
1016
1017 case on_failure_jump_loop:
1018 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1019 fprintf (stderr, "/on_failure_jump_loop to %td",
1020 p + mcnt - start);
1021 break;
1022
1023 case on_failure_jump_smart:
1024 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1025 fprintf (stderr, "/on_failure_jump_smart to %td",
1026 p + mcnt - start);
1027 break;
1028
1029 case jump:
1030 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1031 fprintf (stderr, "/jump to %td", p + mcnt - start);
1032 break;
1033
1034 case succeed_n:
1035 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1036 EXTRACT_NUMBER_AND_INCR (mcnt2, p);
1037 fprintf (stderr, "/succeed_n to %td, %d times",
1038 p - 2 + mcnt - start, mcnt2);
1039 break;
1040
1041 case jump_n:
1042 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1043 EXTRACT_NUMBER_AND_INCR (mcnt2, p);
1044 fprintf (stderr, "/jump_n to %td, %d times",
1045 p - 2 + mcnt - start, mcnt2);
1046 break;
1047
1048 case set_number_at:
1049 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1050 EXTRACT_NUMBER_AND_INCR (mcnt2, p);
1051 fprintf (stderr, "/set_number_at location %td to %d",
1052 p - 2 + mcnt - start, mcnt2);
1053 break;
1054
1055 case wordbound:
1056 fprintf (stderr, "/wordbound");
1057 break;
1058
1059 case notwordbound:
1060 fprintf (stderr, "/notwordbound");
1061 break;
1062
1063 case wordbeg:
1064 fprintf (stderr, "/wordbeg");
1065 break;
1066
1067 case wordend:
1068 fprintf (stderr, "/wordend");
1069 break;
1070
1071 case symbeg:
1072 fprintf (stderr, "/symbeg");
1073 break;
1074
1075 case symend:
1076 fprintf (stderr, "/symend");
1077 break;
1078
1079 case syntaxspec:
1080 fprintf (stderr, "/syntaxspec");
1081 mcnt = *p++;
1082 fprintf (stderr, "/%d", mcnt);
1083 break;
1084
1085 case notsyntaxspec:
1086 fprintf (stderr, "/notsyntaxspec");
1087 mcnt = *p++;
1088 fprintf (stderr, "/%d", mcnt);
1089 break;
1090
1091 # ifdef emacs
1092 case before_dot:
1093 fprintf (stderr, "/before_dot");
1094 break;
1095
1096 case at_dot:
1097 fprintf (stderr, "/at_dot");
1098 break;
1099
1100 case after_dot:
1101 fprintf (stderr, "/after_dot");
1102 break;
1103
1104 case categoryspec:
1105 fprintf (stderr, "/categoryspec");
1106 mcnt = *p++;
1107 fprintf (stderr, "/%d", mcnt);
1108 break;
1109
1110 case notcategoryspec:
1111 fprintf (stderr, "/notcategoryspec");
1112 mcnt = *p++;
1113 fprintf (stderr, "/%d", mcnt);
1114 break;
1115 # endif /* emacs */
1116
1117 case begbuf:
1118 fprintf (stderr, "/begbuf");
1119 break;
1120
1121 case endbuf:
1122 fprintf (stderr, "/endbuf");
1123 break;
1124
1125 default:
1126 fprintf (stderr, "?%d", *(p-1));
1127 }
1128
1129 fprintf (stderr, "\n");
1130 }
1131
1132 fprintf (stderr, "%td:\tend of pattern.\n", p - start);
1133 }
1134
1135
1136 static void
1137 print_compiled_pattern (struct re_pattern_buffer *bufp)
1138 {
1139 re_char *buffer = bufp->buffer;
1140
1141 print_partial_compiled_pattern (buffer, buffer + bufp->used);
1142 printf ("%ld bytes used/%ld bytes allocated.\n",
1143 bufp->used, bufp->allocated);
1144
1145 if (bufp->fastmap_accurate && bufp->fastmap)
1146 {
1147 printf ("fastmap: ");
1148 print_fastmap (bufp->fastmap);
1149 }
1150
1151 printf ("re_nsub: %zu\t", bufp->re_nsub);
1152 printf ("regs_alloc: %d\t", bufp->regs_allocated);
1153 printf ("can_be_null: %d\t", bufp->can_be_null);
1154 printf ("no_sub: %d\t", bufp->no_sub);
1155 printf ("not_bol: %d\t", bufp->not_bol);
1156 printf ("not_eol: %d\t", bufp->not_eol);
1157 printf ("syntax: %lx\n", bufp->syntax);
1158 fflush (stdout);
1159 /* Perhaps we should print the translate table? */
1160 }
1161
1162
1163 static void
1164 print_double_string (re_char *where, re_char *string1, ssize_t size1,
1165 re_char *string2, ssize_t size2)
1166 {
1167 ssize_t this_char;
1168
1169 if (where == NULL)
1170 printf ("(null)");
1171 else
1172 {
1173 if (FIRST_STRING_P (where))
1174 {
1175 for (this_char = where - string1; this_char < size1; this_char++)
1176 putchar (string1[this_char]);
1177
1178 where = string2;
1179 }
1180
1181 for (this_char = where - string2; this_char < size2; this_char++)
1182 putchar (string2[this_char]);
1183 }
1184 }
1185
1186 #else /* not DEBUG */
1187
1188 # undef assert
1189 # define assert(e)
1190
1191 # define DEBUG_STATEMENT(e)
1192 # if __STDC_VERSION__ < 199901L
1193 # define DEBUG_COMPILES_ARGUMENTS
1194 # define DEBUG_PRINT /* 'DEBUG_PRINT (x, y)' discards X and Y. */ (void)
1195 # else
1196 # define DEBUG_PRINT(...)
1197 # endif
1198 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
1199 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
1200
1201 #endif /* not DEBUG */
1202 \f
1203 /* Use this to suppress gcc's `...may be used before initialized' warnings. */
1204 #ifdef lint
1205 # define IF_LINT(Code) Code
1206 #else
1207 # define IF_LINT(Code) /* empty */
1208 #endif
1209 \f
1210 /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
1211 also be assigned to arbitrarily: each pattern buffer stores its own
1212 syntax, so it can be changed between regex compilations. */
1213 /* This has no initializer because initialized variables in Emacs
1214 become read-only after dumping. */
1215 reg_syntax_t re_syntax_options;
1216
1217
1218 /* Specify the precise syntax of regexps for compilation. This provides
1219 for compatibility for various utilities which historically have
1220 different, incompatible syntaxes.
1221
1222 The argument SYNTAX is a bit mask comprised of the various bits
1223 defined in regex.h. We return the old syntax. */
1224
1225 reg_syntax_t
1226 re_set_syntax (reg_syntax_t syntax)
1227 {
1228 reg_syntax_t ret = re_syntax_options;
1229
1230 re_syntax_options = syntax;
1231 return ret;
1232 }
1233 WEAK_ALIAS (__re_set_syntax, re_set_syntax)
1234
1235 /* Regexp to use to replace spaces, or NULL meaning don't. */
1236 static const_re_char *whitespace_regexp;
1237
1238 void
1239 re_set_whitespace_regexp (const char *regexp)
1240 {
1241 whitespace_regexp = (const_re_char *) regexp;
1242 }
1243 WEAK_ALIAS (__re_set_syntax, re_set_syntax)
1244 \f
1245 /* This table gives an error message for each of the error codes listed
1246 in regex.h. Obviously the order here has to be same as there.
1247 POSIX doesn't require that we do anything for REG_NOERROR,
1248 but why not be nice? */
1249
1250 static const char *re_error_msgid[] =
1251 {
1252 gettext_noop ("Success"), /* REG_NOERROR */
1253 gettext_noop ("No match"), /* REG_NOMATCH */
1254 gettext_noop ("Invalid regular expression"), /* REG_BADPAT */
1255 gettext_noop ("Invalid collation character"), /* REG_ECOLLATE */
1256 gettext_noop ("Invalid character class name"), /* REG_ECTYPE */
1257 gettext_noop ("Trailing backslash"), /* REG_EESCAPE */
1258 gettext_noop ("Invalid back reference"), /* REG_ESUBREG */
1259 gettext_noop ("Unmatched [ or [^"), /* REG_EBRACK */
1260 gettext_noop ("Unmatched ( or \\("), /* REG_EPAREN */
1261 gettext_noop ("Unmatched \\{"), /* REG_EBRACE */
1262 gettext_noop ("Invalid content of \\{\\}"), /* REG_BADBR */
1263 gettext_noop ("Invalid range end"), /* REG_ERANGE */
1264 gettext_noop ("Memory exhausted"), /* REG_ESPACE */
1265 gettext_noop ("Invalid preceding regular expression"), /* REG_BADRPT */
1266 gettext_noop ("Premature end of regular expression"), /* REG_EEND */
1267 gettext_noop ("Regular expression too big"), /* REG_ESIZE */
1268 gettext_noop ("Unmatched ) or \\)"), /* REG_ERPAREN */
1269 gettext_noop ("Range striding over charsets") /* REG_ERANGEX */
1270 };
1271 \f
1272 /* Avoiding alloca during matching, to placate r_alloc. */
1273
1274 /* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
1275 searching and matching functions should not call alloca. On some
1276 systems, alloca is implemented in terms of malloc, and if we're
1277 using the relocating allocator routines, then malloc could cause a
1278 relocation, which might (if the strings being searched are in the
1279 ralloc heap) shift the data out from underneath the regexp
1280 routines.
1281
1282 Here's another reason to avoid allocation: Emacs
1283 processes input from X in a signal handler; processing X input may
1284 call malloc; if input arrives while a matching routine is calling
1285 malloc, then we're scrod. But Emacs can't just block input while
1286 calling matching routines; then we don't notice interrupts when
1287 they come in. So, Emacs blocks input around all regexp calls
1288 except the matching calls, which it leaves unprotected, in the
1289 faith that they will not malloc. */
1290
1291 /* Normally, this is fine. */
1292 #define MATCH_MAY_ALLOCATE
1293
1294 /* The match routines may not allocate if (1) they would do it with malloc
1295 and (2) it's not safe for them to use malloc.
1296 Note that if REL_ALLOC is defined, matching would not use malloc for the
1297 failure stack, but we would still use it for the register vectors;
1298 so REL_ALLOC should not affect this. */
1299 #if defined REGEX_MALLOC && defined emacs
1300 # undef MATCH_MAY_ALLOCATE
1301 #endif
1302
1303 \f
1304 /* Failure stack declarations and macros; both re_compile_fastmap and
1305 re_match_2 use a failure stack. These have to be macros because of
1306 REGEX_ALLOCATE_STACK. */
1307
1308
1309 /* Approximate number of failure points for which to initially allocate space
1310 when matching. If this number is exceeded, we allocate more
1311 space, so it is not a hard limit. */
1312 #ifndef INIT_FAILURE_ALLOC
1313 # define INIT_FAILURE_ALLOC 20
1314 #endif
1315
1316 /* Roughly the maximum number of failure points on the stack. Would be
1317 exactly that if always used TYPICAL_FAILURE_SIZE items each time we failed.
1318 This is a variable only so users of regex can assign to it; we never
1319 change it ourselves. We always multiply it by TYPICAL_FAILURE_SIZE
1320 before using it, so it should probably be a byte-count instead. */
1321 # if defined MATCH_MAY_ALLOCATE
1322 /* Note that 4400 was enough to cause a crash on Alpha OSF/1,
1323 whose default stack limit is 2mb. In order for a larger
1324 value to work reliably, you have to try to make it accord
1325 with the process stack limit. */
1326 size_t re_max_failures = 40000;
1327 # else
1328 size_t re_max_failures = 4000;
1329 # endif
1330
1331 union fail_stack_elt
1332 {
1333 re_char *pointer;
1334 /* This should be the biggest `int' that's no bigger than a pointer. */
1335 long integer;
1336 };
1337
1338 typedef union fail_stack_elt fail_stack_elt_t;
1339
1340 typedef struct
1341 {
1342 fail_stack_elt_t *stack;
1343 size_t size;
1344 size_t avail; /* Offset of next open position. */
1345 size_t frame; /* Offset of the cur constructed frame. */
1346 } fail_stack_type;
1347
1348 #define FAIL_STACK_EMPTY() (fail_stack.frame == 0)
1349
1350
1351 /* Define macros to initialize and free the failure stack.
1352 Do `return -2' if the alloc fails. */
1353
1354 #ifdef MATCH_MAY_ALLOCATE
1355 # define INIT_FAIL_STACK() \
1356 do { \
1357 fail_stack.stack = \
1358 REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * TYPICAL_FAILURE_SIZE \
1359 * sizeof (fail_stack_elt_t)); \
1360 \
1361 if (fail_stack.stack == NULL) \
1362 return -2; \
1363 \
1364 fail_stack.size = INIT_FAILURE_ALLOC; \
1365 fail_stack.avail = 0; \
1366 fail_stack.frame = 0; \
1367 } while (0)
1368 #else
1369 # define INIT_FAIL_STACK() \
1370 do { \
1371 fail_stack.avail = 0; \
1372 fail_stack.frame = 0; \
1373 } while (0)
1374
1375 # define RETALLOC_IF(addr, n, t) \
1376 if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
1377 #endif
1378
1379
1380 /* Double the size of FAIL_STACK, up to a limit
1381 which allows approximately `re_max_failures' items.
1382
1383 Return 1 if succeeds, and 0 if either ran out of memory
1384 allocating space for it or it was already too large.
1385
1386 REGEX_REALLOCATE_STACK requires `destination' be declared. */
1387
1388 /* Factor to increase the failure stack size by
1389 when we increase it.
1390 This used to be 2, but 2 was too wasteful
1391 because the old discarded stacks added up to as much space
1392 were as ultimate, maximum-size stack. */
1393 #define FAIL_STACK_GROWTH_FACTOR 4
1394
1395 #define GROW_FAIL_STACK(fail_stack) \
1396 (((fail_stack).size * sizeof (fail_stack_elt_t) \
1397 >= re_max_failures * TYPICAL_FAILURE_SIZE) \
1398 ? 0 \
1399 : ((fail_stack).stack \
1400 = REGEX_REALLOCATE_STACK ((fail_stack).stack, \
1401 (fail_stack).size * sizeof (fail_stack_elt_t), \
1402 MIN (re_max_failures * TYPICAL_FAILURE_SIZE, \
1403 ((fail_stack).size * sizeof (fail_stack_elt_t) \
1404 * FAIL_STACK_GROWTH_FACTOR))), \
1405 \
1406 (fail_stack).stack == NULL \
1407 ? 0 \
1408 : ((fail_stack).size \
1409 = (MIN (re_max_failures * TYPICAL_FAILURE_SIZE, \
1410 ((fail_stack).size * sizeof (fail_stack_elt_t) \
1411 * FAIL_STACK_GROWTH_FACTOR)) \
1412 / sizeof (fail_stack_elt_t)), \
1413 1)))
1414
1415
1416 /* Push a pointer value onto the failure stack.
1417 Assumes the variable `fail_stack'. Probably should only
1418 be called from within `PUSH_FAILURE_POINT'. */
1419 #define PUSH_FAILURE_POINTER(item) \
1420 fail_stack.stack[fail_stack.avail++].pointer = (item)
1421
1422 /* This pushes an integer-valued item onto the failure stack.
1423 Assumes the variable `fail_stack'. Probably should only
1424 be called from within `PUSH_FAILURE_POINT'. */
1425 #define PUSH_FAILURE_INT(item) \
1426 fail_stack.stack[fail_stack.avail++].integer = (item)
1427
1428 /* These POP... operations complement the PUSH... operations.
1429 All assume that `fail_stack' is nonempty. */
1430 #define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
1431 #define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
1432
1433 /* Individual items aside from the registers. */
1434 #define NUM_NONREG_ITEMS 3
1435
1436 /* Used to examine the stack (to detect infinite loops). */
1437 #define FAILURE_PAT(h) fail_stack.stack[(h) - 1].pointer
1438 #define FAILURE_STR(h) (fail_stack.stack[(h) - 2].pointer)
1439 #define NEXT_FAILURE_HANDLE(h) fail_stack.stack[(h) - 3].integer
1440 #define TOP_FAILURE_HANDLE() fail_stack.frame
1441
1442
1443 #define ENSURE_FAIL_STACK(space) \
1444 while (REMAINING_AVAIL_SLOTS <= space) { \
1445 if (!GROW_FAIL_STACK (fail_stack)) \
1446 return -2; \
1447 DEBUG_PRINT ("\n Doubled stack; size now: %zd\n", (fail_stack).size);\
1448 DEBUG_PRINT (" slots available: %zd\n", REMAINING_AVAIL_SLOTS);\
1449 }
1450
1451 /* Push register NUM onto the stack. */
1452 #define PUSH_FAILURE_REG(num) \
1453 do { \
1454 char *destination; \
1455 long n = num; \
1456 ENSURE_FAIL_STACK(3); \
1457 DEBUG_PRINT (" Push reg %ld (spanning %p -> %p)\n", \
1458 n, regstart[n], regend[n]); \
1459 PUSH_FAILURE_POINTER (regstart[n]); \
1460 PUSH_FAILURE_POINTER (regend[n]); \
1461 PUSH_FAILURE_INT (n); \
1462 } while (0)
1463
1464 /* Change the counter's value to VAL, but make sure that it will
1465 be reset when backtracking. */
1466 #define PUSH_NUMBER(ptr,val) \
1467 do { \
1468 char *destination; \
1469 int c; \
1470 ENSURE_FAIL_STACK(3); \
1471 EXTRACT_NUMBER (c, ptr); \
1472 DEBUG_PRINT (" Push number %p = %d -> %d\n", ptr, c, val); \
1473 PUSH_FAILURE_INT (c); \
1474 PUSH_FAILURE_POINTER (ptr); \
1475 PUSH_FAILURE_INT (-1); \
1476 STORE_NUMBER (ptr, val); \
1477 } while (0)
1478
1479 /* Pop a saved register off the stack. */
1480 #define POP_FAILURE_REG_OR_COUNT() \
1481 do { \
1482 long pfreg = POP_FAILURE_INT (); \
1483 if (pfreg == -1) \
1484 { \
1485 /* It's a counter. */ \
1486 /* Here, we discard `const', making re_match non-reentrant. */ \
1487 unsigned char *ptr = (unsigned char*) POP_FAILURE_POINTER (); \
1488 pfreg = POP_FAILURE_INT (); \
1489 STORE_NUMBER (ptr, pfreg); \
1490 DEBUG_PRINT (" Pop counter %p = %ld\n", ptr, pfreg); \
1491 } \
1492 else \
1493 { \
1494 regend[pfreg] = POP_FAILURE_POINTER (); \
1495 regstart[pfreg] = POP_FAILURE_POINTER (); \
1496 DEBUG_PRINT (" Pop reg %ld (spanning %p -> %p)\n", \
1497 pfreg, regstart[pfreg], regend[pfreg]); \
1498 } \
1499 } while (0)
1500
1501 /* Check that we are not stuck in an infinite loop. */
1502 #define CHECK_INFINITE_LOOP(pat_cur, string_place) \
1503 do { \
1504 ssize_t failure = TOP_FAILURE_HANDLE (); \
1505 /* Check for infinite matching loops */ \
1506 while (failure > 0 \
1507 && (FAILURE_STR (failure) == string_place \
1508 || FAILURE_STR (failure) == NULL)) \
1509 { \
1510 assert (FAILURE_PAT (failure) >= bufp->buffer \
1511 && FAILURE_PAT (failure) <= bufp->buffer + bufp->used); \
1512 if (FAILURE_PAT (failure) == pat_cur) \
1513 { \
1514 cycle = 1; \
1515 break; \
1516 } \
1517 DEBUG_PRINT (" Other pattern: %p\n", FAILURE_PAT (failure)); \
1518 failure = NEXT_FAILURE_HANDLE(failure); \
1519 } \
1520 DEBUG_PRINT (" Other string: %p\n", FAILURE_STR (failure)); \
1521 } while (0)
1522
1523 /* Push the information about the state we will need
1524 if we ever fail back to it.
1525
1526 Requires variables fail_stack, regstart, regend and
1527 num_regs be declared. GROW_FAIL_STACK requires `destination' be
1528 declared.
1529
1530 Does `return FAILURE_CODE' if runs out of memory. */
1531
1532 #define PUSH_FAILURE_POINT(pattern, string_place) \
1533 do { \
1534 char *destination; \
1535 /* Must be int, so when we don't save any registers, the arithmetic \
1536 of 0 + -1 isn't done as unsigned. */ \
1537 \
1538 DEBUG_STATEMENT (nfailure_points_pushed++); \
1539 DEBUG_PRINT ("\nPUSH_FAILURE_POINT:\n"); \
1540 DEBUG_PRINT (" Before push, next avail: %zd\n", (fail_stack).avail); \
1541 DEBUG_PRINT (" size: %zd\n", (fail_stack).size);\
1542 \
1543 ENSURE_FAIL_STACK (NUM_NONREG_ITEMS); \
1544 \
1545 DEBUG_PRINT ("\n"); \
1546 \
1547 DEBUG_PRINT (" Push frame index: %zd\n", fail_stack.frame); \
1548 PUSH_FAILURE_INT (fail_stack.frame); \
1549 \
1550 DEBUG_PRINT (" Push string %p: `", string_place); \
1551 DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2, size2);\
1552 DEBUG_PRINT ("'\n"); \
1553 PUSH_FAILURE_POINTER (string_place); \
1554 \
1555 DEBUG_PRINT (" Push pattern %p: ", pattern); \
1556 DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern, pend); \
1557 PUSH_FAILURE_POINTER (pattern); \
1558 \
1559 /* Close the frame by moving the frame pointer past it. */ \
1560 fail_stack.frame = fail_stack.avail; \
1561 } while (0)
1562
1563 /* Estimate the size of data pushed by a typical failure stack entry.
1564 An estimate is all we need, because all we use this for
1565 is to choose a limit for how big to make the failure stack. */
1566 /* BEWARE, the value `20' is hard-coded in emacs.c:main(). */
1567 #define TYPICAL_FAILURE_SIZE 20
1568
1569 /* How many items can still be added to the stack without overflowing it. */
1570 #define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
1571
1572
1573 /* Pops what PUSH_FAIL_STACK pushes.
1574
1575 We restore into the parameters, all of which should be lvalues:
1576 STR -- the saved data position.
1577 PAT -- the saved pattern position.
1578 REGSTART, REGEND -- arrays of string positions.
1579
1580 Also assumes the variables `fail_stack' and (if debugging), `bufp',
1581 `pend', `string1', `size1', `string2', and `size2'. */
1582
1583 #define POP_FAILURE_POINT(str, pat) \
1584 do { \
1585 assert (!FAIL_STACK_EMPTY ()); \
1586 \
1587 /* Remove failure points and point to how many regs pushed. */ \
1588 DEBUG_PRINT ("POP_FAILURE_POINT:\n"); \
1589 DEBUG_PRINT (" Before pop, next avail: %zd\n", fail_stack.avail); \
1590 DEBUG_PRINT (" size: %zd\n", fail_stack.size); \
1591 \
1592 /* Pop the saved registers. */ \
1593 while (fail_stack.frame < fail_stack.avail) \
1594 POP_FAILURE_REG_OR_COUNT (); \
1595 \
1596 pat = POP_FAILURE_POINTER (); \
1597 DEBUG_PRINT (" Popping pattern %p: ", pat); \
1598 DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend); \
1599 \
1600 /* If the saved string location is NULL, it came from an \
1601 on_failure_keep_string_jump opcode, and we want to throw away the \
1602 saved NULL, thus retaining our current position in the string. */ \
1603 str = POP_FAILURE_POINTER (); \
1604 DEBUG_PRINT (" Popping string %p: `", str); \
1605 DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2); \
1606 DEBUG_PRINT ("'\n"); \
1607 \
1608 fail_stack.frame = POP_FAILURE_INT (); \
1609 DEBUG_PRINT (" Popping frame index: %zd\n", fail_stack.frame); \
1610 \
1611 assert (fail_stack.avail >= 0); \
1612 assert (fail_stack.frame <= fail_stack.avail); \
1613 \
1614 DEBUG_STATEMENT (nfailure_points_popped++); \
1615 } while (0) /* POP_FAILURE_POINT */
1616
1617
1618 \f
1619 /* Registers are set to a sentinel when they haven't yet matched. */
1620 #define REG_UNSET(e) ((e) == NULL)
1621 \f
1622 /* Subroutine declarations and macros for regex_compile. */
1623
1624 static reg_errcode_t regex_compile (re_char *pattern, size_t size,
1625 reg_syntax_t syntax,
1626 struct re_pattern_buffer *bufp);
1627 static void store_op1 (re_opcode_t op, unsigned char *loc, int arg);
1628 static void store_op2 (re_opcode_t op, unsigned char *loc, int arg1, int arg2);
1629 static void insert_op1 (re_opcode_t op, unsigned char *loc,
1630 int arg, unsigned char *end);
1631 static void insert_op2 (re_opcode_t op, unsigned char *loc,
1632 int arg1, int arg2, unsigned char *end);
1633 static boolean at_begline_loc_p (re_char *pattern, re_char *p,
1634 reg_syntax_t syntax);
1635 static boolean at_endline_loc_p (re_char *p, re_char *pend,
1636 reg_syntax_t syntax);
1637 static re_char *skip_one_char (re_char *p);
1638 static int analyse_first (re_char *p, re_char *pend,
1639 char *fastmap, const int multibyte);
1640
1641 /* Fetch the next character in the uncompiled pattern, with no
1642 translation. */
1643 #define PATFETCH(c) \
1644 do { \
1645 int len; \
1646 if (p == pend) return REG_EEND; \
1647 c = RE_STRING_CHAR_AND_LENGTH (p, len, multibyte); \
1648 p += len; \
1649 } while (0)
1650
1651
1652 /* If `translate' is non-null, return translate[D], else just D. We
1653 cast the subscript to translate because some data is declared as
1654 `char *', to avoid warnings when a string constant is passed. But
1655 when we use a character as a subscript we must make it unsigned. */
1656 #ifndef TRANSLATE
1657 # define TRANSLATE(d) \
1658 (RE_TRANSLATE_P (translate) ? RE_TRANSLATE (translate, (d)) : (d))
1659 #endif
1660
1661
1662 /* Macros for outputting the compiled pattern into `buffer'. */
1663
1664 /* If the buffer isn't allocated when it comes in, use this. */
1665 #define INIT_BUF_SIZE 32
1666
1667 /* Make sure we have at least N more bytes of space in buffer. */
1668 #define GET_BUFFER_SPACE(n) \
1669 while ((size_t) (b - bufp->buffer + (n)) > bufp->allocated) \
1670 EXTEND_BUFFER ()
1671
1672 /* Make sure we have one more byte of buffer space and then add C to it. */
1673 #define BUF_PUSH(c) \
1674 do { \
1675 GET_BUFFER_SPACE (1); \
1676 *b++ = (unsigned char) (c); \
1677 } while (0)
1678
1679
1680 /* Ensure we have two more bytes of buffer space and then append C1 and C2. */
1681 #define BUF_PUSH_2(c1, c2) \
1682 do { \
1683 GET_BUFFER_SPACE (2); \
1684 *b++ = (unsigned char) (c1); \
1685 *b++ = (unsigned char) (c2); \
1686 } while (0)
1687
1688
1689 /* Store a jump with opcode OP at LOC to location TO. We store a
1690 relative address offset by the three bytes the jump itself occupies. */
1691 #define STORE_JUMP(op, loc, to) \
1692 store_op1 (op, loc, (to) - (loc) - 3)
1693
1694 /* Likewise, for a two-argument jump. */
1695 #define STORE_JUMP2(op, loc, to, arg) \
1696 store_op2 (op, loc, (to) - (loc) - 3, arg)
1697
1698 /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
1699 #define INSERT_JUMP(op, loc, to) \
1700 insert_op1 (op, loc, (to) - (loc) - 3, b)
1701
1702 /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
1703 #define INSERT_JUMP2(op, loc, to, arg) \
1704 insert_op2 (op, loc, (to) - (loc) - 3, arg, b)
1705
1706
1707 /* This is not an arbitrary limit: the arguments which represent offsets
1708 into the pattern are two bytes long. So if 2^15 bytes turns out to
1709 be too small, many things would have to change. */
1710 # define MAX_BUF_SIZE (1L << 15)
1711
1712 /* Extend the buffer by twice its current size via realloc and
1713 reset the pointers that pointed into the old block to point to the
1714 correct places in the new one. If extending the buffer results in it
1715 being larger than MAX_BUF_SIZE, then flag memory exhausted. */
1716 #if __BOUNDED_POINTERS__
1717 # define SET_HIGH_BOUND(P) (__ptrhigh (P) = __ptrlow (P) + bufp->allocated)
1718 # define MOVE_BUFFER_POINTER(P) \
1719 (__ptrlow (P) = new_buffer + (__ptrlow (P) - old_buffer), \
1720 SET_HIGH_BOUND (P), \
1721 __ptrvalue (P) = new_buffer + (__ptrvalue (P) - old_buffer))
1722 # define ELSE_EXTEND_BUFFER_HIGH_BOUND \
1723 else \
1724 { \
1725 SET_HIGH_BOUND (b); \
1726 SET_HIGH_BOUND (begalt); \
1727 if (fixup_alt_jump) \
1728 SET_HIGH_BOUND (fixup_alt_jump); \
1729 if (laststart) \
1730 SET_HIGH_BOUND (laststart); \
1731 if (pending_exact) \
1732 SET_HIGH_BOUND (pending_exact); \
1733 }
1734 #else
1735 # define MOVE_BUFFER_POINTER(P) ((P) = new_buffer + ((P) - old_buffer))
1736 # define ELSE_EXTEND_BUFFER_HIGH_BOUND
1737 #endif
1738 #define EXTEND_BUFFER() \
1739 do { \
1740 unsigned char *old_buffer = bufp->buffer; \
1741 if (bufp->allocated == MAX_BUF_SIZE) \
1742 return REG_ESIZE; \
1743 bufp->allocated <<= 1; \
1744 if (bufp->allocated > MAX_BUF_SIZE) \
1745 bufp->allocated = MAX_BUF_SIZE; \
1746 RETALLOC (bufp->buffer, bufp->allocated, unsigned char); \
1747 if (bufp->buffer == NULL) \
1748 return REG_ESPACE; \
1749 /* If the buffer moved, move all the pointers into it. */ \
1750 if (old_buffer != bufp->buffer) \
1751 { \
1752 unsigned char *new_buffer = bufp->buffer; \
1753 MOVE_BUFFER_POINTER (b); \
1754 MOVE_BUFFER_POINTER (begalt); \
1755 if (fixup_alt_jump) \
1756 MOVE_BUFFER_POINTER (fixup_alt_jump); \
1757 if (laststart) \
1758 MOVE_BUFFER_POINTER (laststart); \
1759 if (pending_exact) \
1760 MOVE_BUFFER_POINTER (pending_exact); \
1761 } \
1762 ELSE_EXTEND_BUFFER_HIGH_BOUND \
1763 } while (0)
1764
1765
1766 /* Since we have one byte reserved for the register number argument to
1767 {start,stop}_memory, the maximum number of groups we can report
1768 things about is what fits in that byte. */
1769 #define MAX_REGNUM 255
1770
1771 /* But patterns can have more than `MAX_REGNUM' registers. We just
1772 ignore the excess. */
1773 typedef int regnum_t;
1774
1775
1776 /* Macros for the compile stack. */
1777
1778 /* Since offsets can go either forwards or backwards, this type needs to
1779 be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
1780 /* int may be not enough when sizeof(int) == 2. */
1781 typedef long pattern_offset_t;
1782
1783 typedef struct
1784 {
1785 pattern_offset_t begalt_offset;
1786 pattern_offset_t fixup_alt_jump;
1787 pattern_offset_t laststart_offset;
1788 regnum_t regnum;
1789 } compile_stack_elt_t;
1790
1791
1792 typedef struct
1793 {
1794 compile_stack_elt_t *stack;
1795 size_t size;
1796 size_t avail; /* Offset of next open position. */
1797 } compile_stack_type;
1798
1799
1800 #define INIT_COMPILE_STACK_SIZE 32
1801
1802 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
1803 #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
1804
1805 /* The next available element. */
1806 #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
1807
1808 /* Explicit quit checking is needed for Emacs, which uses polling to
1809 process input events. */
1810 #ifdef emacs
1811 # define IMMEDIATE_QUIT_CHECK \
1812 do { \
1813 if (immediate_quit) QUIT; \
1814 } while (0)
1815 #else
1816 # define IMMEDIATE_QUIT_CHECK ((void)0)
1817 #endif
1818 \f
1819 /* Structure to manage work area for range table. */
1820 struct range_table_work_area
1821 {
1822 int *table; /* actual work area. */
1823 int allocated; /* allocated size for work area in bytes. */
1824 int used; /* actually used size in words. */
1825 int bits; /* flag to record character classes */
1826 };
1827
1828 #ifdef emacs
1829
1830 /* Make sure that WORK_AREA can hold more N multibyte characters.
1831 This is used only in set_image_of_range and set_image_of_range_1.
1832 It expects WORK_AREA to be a pointer.
1833 If it can't get the space, it returns from the surrounding function. */
1834
1835 #define EXTEND_RANGE_TABLE(work_area, n) \
1836 do { \
1837 if (((work_area).used + (n)) * sizeof (int) > (work_area).allocated) \
1838 { \
1839 extend_range_table_work_area (&work_area); \
1840 if ((work_area).table == 0) \
1841 return (REG_ESPACE); \
1842 } \
1843 } while (0)
1844
1845 #define SET_RANGE_TABLE_WORK_AREA_BIT(work_area, bit) \
1846 (work_area).bits |= (bit)
1847
1848 /* Set a range (RANGE_START, RANGE_END) to WORK_AREA. */
1849 #define SET_RANGE_TABLE_WORK_AREA(work_area, range_start, range_end) \
1850 do { \
1851 EXTEND_RANGE_TABLE ((work_area), 2); \
1852 (work_area).table[(work_area).used++] = (range_start); \
1853 (work_area).table[(work_area).used++] = (range_end); \
1854 } while (0)
1855
1856 #endif /* emacs */
1857
1858 /* Free allocated memory for WORK_AREA. */
1859 #define FREE_RANGE_TABLE_WORK_AREA(work_area) \
1860 do { \
1861 if ((work_area).table) \
1862 free ((work_area).table); \
1863 } while (0)
1864
1865 #define CLEAR_RANGE_TABLE_WORK_USED(work_area) ((work_area).used = 0, (work_area).bits = 0)
1866 #define RANGE_TABLE_WORK_USED(work_area) ((work_area).used)
1867 #define RANGE_TABLE_WORK_BITS(work_area) ((work_area).bits)
1868 #define RANGE_TABLE_WORK_ELT(work_area, i) ((work_area).table[i])
1869
1870 /* Bits used to implement the multibyte-part of the various character classes
1871 such as [:alnum:] in a charset's range table. */
1872 #define BIT_WORD 0x1
1873 #define BIT_LOWER 0x2
1874 #define BIT_PUNCT 0x4
1875 #define BIT_SPACE 0x8
1876 #define BIT_UPPER 0x10
1877 #define BIT_MULTIBYTE 0x20
1878 \f
1879
1880 /* Set the bit for character C in a list. */
1881 #define SET_LIST_BIT(c) (b[((c)) / BYTEWIDTH] |= 1 << ((c) % BYTEWIDTH))
1882
1883
1884 #ifdef emacs
1885
1886 /* Store characters in the range FROM to TO in the bitmap at B (for
1887 ASCII and unibyte characters) and WORK_AREA (for multibyte
1888 characters) while translating them and paying attention to the
1889 continuity of translated characters.
1890
1891 Implementation note: It is better to implement these fairly big
1892 macros by a function, but it's not that easy because macros called
1893 in this macro assume various local variables already declared. */
1894
1895 /* Both FROM and TO are ASCII characters. */
1896
1897 #define SETUP_ASCII_RANGE(work_area, FROM, TO) \
1898 do { \
1899 int C0, C1; \
1900 \
1901 for (C0 = (FROM); C0 <= (TO); C0++) \
1902 { \
1903 C1 = TRANSLATE (C0); \
1904 if (! ASCII_CHAR_P (C1)) \
1905 { \
1906 SET_RANGE_TABLE_WORK_AREA ((work_area), C1, C1); \
1907 if ((C1 = RE_CHAR_TO_UNIBYTE (C1)) < 0) \
1908 C1 = C0; \
1909 } \
1910 SET_LIST_BIT (C1); \
1911 } \
1912 } while (0)
1913
1914
1915 /* Both FROM and TO are unibyte characters (0x80..0xFF). */
1916
1917 #define SETUP_UNIBYTE_RANGE(work_area, FROM, TO) \
1918 do { \
1919 int C0, C1, C2, I; \
1920 int USED = RANGE_TABLE_WORK_USED (work_area); \
1921 \
1922 for (C0 = (FROM); C0 <= (TO); C0++) \
1923 { \
1924 C1 = RE_CHAR_TO_MULTIBYTE (C0); \
1925 if (CHAR_BYTE8_P (C1)) \
1926 SET_LIST_BIT (C0); \
1927 else \
1928 { \
1929 C2 = TRANSLATE (C1); \
1930 if (C2 == C1 \
1931 || (C1 = RE_CHAR_TO_UNIBYTE (C2)) < 0) \
1932 C1 = C0; \
1933 SET_LIST_BIT (C1); \
1934 for (I = RANGE_TABLE_WORK_USED (work_area) - 2; I >= USED; I -= 2) \
1935 { \
1936 int from = RANGE_TABLE_WORK_ELT (work_area, I); \
1937 int to = RANGE_TABLE_WORK_ELT (work_area, I + 1); \
1938 \
1939 if (C2 >= from - 1 && C2 <= to + 1) \
1940 { \
1941 if (C2 == from - 1) \
1942 RANGE_TABLE_WORK_ELT (work_area, I)--; \
1943 else if (C2 == to + 1) \
1944 RANGE_TABLE_WORK_ELT (work_area, I + 1)++; \
1945 break; \
1946 } \
1947 } \
1948 if (I < USED) \
1949 SET_RANGE_TABLE_WORK_AREA ((work_area), C2, C2); \
1950 } \
1951 } \
1952 } while (0)
1953
1954
1955 /* Both FROM and TO are multibyte characters. */
1956
1957 #define SETUP_MULTIBYTE_RANGE(work_area, FROM, TO) \
1958 do { \
1959 int C0, C1, C2, I, USED = RANGE_TABLE_WORK_USED (work_area); \
1960 \
1961 SET_RANGE_TABLE_WORK_AREA ((work_area), (FROM), (TO)); \
1962 for (C0 = (FROM); C0 <= (TO); C0++) \
1963 { \
1964 C1 = TRANSLATE (C0); \
1965 if ((C2 = RE_CHAR_TO_UNIBYTE (C1)) >= 0 \
1966 || (C1 != C0 && (C2 = RE_CHAR_TO_UNIBYTE (C0)) >= 0)) \
1967 SET_LIST_BIT (C2); \
1968 if (C1 >= (FROM) && C1 <= (TO)) \
1969 continue; \
1970 for (I = RANGE_TABLE_WORK_USED (work_area) - 2; I >= USED; I -= 2) \
1971 { \
1972 int from = RANGE_TABLE_WORK_ELT (work_area, I); \
1973 int to = RANGE_TABLE_WORK_ELT (work_area, I + 1); \
1974 \
1975 if (C1 >= from - 1 && C1 <= to + 1) \
1976 { \
1977 if (C1 == from - 1) \
1978 RANGE_TABLE_WORK_ELT (work_area, I)--; \
1979 else if (C1 == to + 1) \
1980 RANGE_TABLE_WORK_ELT (work_area, I + 1)++; \
1981 break; \
1982 } \
1983 } \
1984 if (I < USED) \
1985 SET_RANGE_TABLE_WORK_AREA ((work_area), C1, C1); \
1986 } \
1987 } while (0)
1988
1989 #endif /* emacs */
1990
1991 /* Get the next unsigned number in the uncompiled pattern. */
1992 #define GET_INTERVAL_COUNT(num) \
1993 do { \
1994 if (p == pend) \
1995 FREE_STACK_RETURN (REG_EBRACE); \
1996 else \
1997 { \
1998 PATFETCH (c); \
1999 while ('0' <= c && c <= '9') \
2000 { \
2001 if (num < 0) \
2002 num = 0; \
2003 if (RE_DUP_MAX / 10 - (RE_DUP_MAX % 10 < c - '0') < num) \
2004 FREE_STACK_RETURN (REG_BADBR); \
2005 num = num * 10 + c - '0'; \
2006 if (p == pend) \
2007 FREE_STACK_RETURN (REG_EBRACE); \
2008 PATFETCH (c); \
2009 } \
2010 } \
2011 } while (0)
2012 \f
2013 #if ! WIDE_CHAR_SUPPORT
2014
2015 /* Map a string to the char class it names (if any). */
2016 re_wctype_t
2017 re_wctype (const_re_char *str)
2018 {
2019 const char *string = (const char *) str;
2020 if (STREQ (string, "alnum")) return RECC_ALNUM;
2021 else if (STREQ (string, "alpha")) return RECC_ALPHA;
2022 else if (STREQ (string, "word")) return RECC_WORD;
2023 else if (STREQ (string, "ascii")) return RECC_ASCII;
2024 else if (STREQ (string, "nonascii")) return RECC_NONASCII;
2025 else if (STREQ (string, "graph")) return RECC_GRAPH;
2026 else if (STREQ (string, "lower")) return RECC_LOWER;
2027 else if (STREQ (string, "print")) return RECC_PRINT;
2028 else if (STREQ (string, "punct")) return RECC_PUNCT;
2029 else if (STREQ (string, "space")) return RECC_SPACE;
2030 else if (STREQ (string, "upper")) return RECC_UPPER;
2031 else if (STREQ (string, "unibyte")) return RECC_UNIBYTE;
2032 else if (STREQ (string, "multibyte")) return RECC_MULTIBYTE;
2033 else if (STREQ (string, "digit")) return RECC_DIGIT;
2034 else if (STREQ (string, "xdigit")) return RECC_XDIGIT;
2035 else if (STREQ (string, "cntrl")) return RECC_CNTRL;
2036 else if (STREQ (string, "blank")) return RECC_BLANK;
2037 else return 0;
2038 }
2039
2040 /* True if CH is in the char class CC. */
2041 boolean
2042 re_iswctype (int ch, re_wctype_t cc)
2043 {
2044 switch (cc)
2045 {
2046 case RECC_ALNUM: return ISALNUM (ch) != 0;
2047 case RECC_ALPHA: return ISALPHA (ch) != 0;
2048 case RECC_BLANK: return ISBLANK (ch) != 0;
2049 case RECC_CNTRL: return ISCNTRL (ch) != 0;
2050 case RECC_DIGIT: return ISDIGIT (ch) != 0;
2051 case RECC_GRAPH: return ISGRAPH (ch) != 0;
2052 case RECC_LOWER: return ISLOWER (ch) != 0;
2053 case RECC_PRINT: return ISPRINT (ch) != 0;
2054 case RECC_PUNCT: return ISPUNCT (ch) != 0;
2055 case RECC_SPACE: return ISSPACE (ch) != 0;
2056 case RECC_UPPER: return ISUPPER (ch) != 0;
2057 case RECC_XDIGIT: return ISXDIGIT (ch) != 0;
2058 case RECC_ASCII: return IS_REAL_ASCII (ch) != 0;
2059 case RECC_NONASCII: return !IS_REAL_ASCII (ch);
2060 case RECC_UNIBYTE: return ISUNIBYTE (ch) != 0;
2061 case RECC_MULTIBYTE: return !ISUNIBYTE (ch);
2062 case RECC_WORD: return ISWORD (ch) != 0;
2063 case RECC_ERROR: return false;
2064 default:
2065 abort ();
2066 }
2067 }
2068
2069 /* Return a bit-pattern to use in the range-table bits to match multibyte
2070 chars of class CC. */
2071 static int
2072 re_wctype_to_bit (re_wctype_t cc)
2073 {
2074 switch (cc)
2075 {
2076 case RECC_NONASCII: case RECC_PRINT: case RECC_GRAPH:
2077 case RECC_MULTIBYTE: return BIT_MULTIBYTE;
2078 case RECC_ALPHA: case RECC_ALNUM: case RECC_WORD: return BIT_WORD;
2079 case RECC_LOWER: return BIT_LOWER;
2080 case RECC_UPPER: return BIT_UPPER;
2081 case RECC_PUNCT: return BIT_PUNCT;
2082 case RECC_SPACE: return BIT_SPACE;
2083 case RECC_ASCII: case RECC_DIGIT: case RECC_XDIGIT: case RECC_CNTRL:
2084 case RECC_BLANK: case RECC_UNIBYTE: case RECC_ERROR: return 0;
2085 default:
2086 abort ();
2087 }
2088 }
2089 #endif
2090 \f
2091 /* Filling in the work area of a range. */
2092
2093 /* Actually extend the space in WORK_AREA. */
2094
2095 static void
2096 extend_range_table_work_area (struct range_table_work_area *work_area)
2097 {
2098 work_area->allocated += 16 * sizeof (int);
2099 work_area->table = realloc (work_area->table, work_area->allocated);
2100 }
2101
2102 #if 0
2103 #ifdef emacs
2104
2105 /* Carefully find the ranges of codes that are equivalent
2106 under case conversion to the range start..end when passed through
2107 TRANSLATE. Handle the case where non-letters can come in between
2108 two upper-case letters (which happens in Latin-1).
2109 Also handle the case of groups of more than 2 case-equivalent chars.
2110
2111 The basic method is to look at consecutive characters and see
2112 if they can form a run that can be handled as one.
2113
2114 Returns -1 if successful, REG_ESPACE if ran out of space. */
2115
2116 static int
2117 set_image_of_range_1 (struct range_table_work_area *work_area,
2118 re_wchar_t start, re_wchar_t end,
2119 RE_TRANSLATE_TYPE translate)
2120 {
2121 /* `one_case' indicates a character, or a run of characters,
2122 each of which is an isolate (no case-equivalents).
2123 This includes all ASCII non-letters.
2124
2125 `two_case' indicates a character, or a run of characters,
2126 each of which has two case-equivalent forms.
2127 This includes all ASCII letters.
2128
2129 `strange' indicates a character that has more than one
2130 case-equivalent. */
2131
2132 enum case_type {one_case, two_case, strange};
2133
2134 /* Describe the run that is in progress,
2135 which the next character can try to extend.
2136 If run_type is strange, that means there really is no run.
2137 If run_type is one_case, then run_start...run_end is the run.
2138 If run_type is two_case, then the run is run_start...run_end,
2139 and the case-equivalents end at run_eqv_end. */
2140
2141 enum case_type run_type = strange;
2142 int run_start, run_end, run_eqv_end;
2143
2144 Lisp_Object eqv_table;
2145
2146 if (!RE_TRANSLATE_P (translate))
2147 {
2148 EXTEND_RANGE_TABLE (work_area, 2);
2149 work_area->table[work_area->used++] = (start);
2150 work_area->table[work_area->used++] = (end);
2151 return -1;
2152 }
2153
2154 eqv_table = XCHAR_TABLE (translate)->extras[2];
2155
2156 for (; start <= end; start++)
2157 {
2158 enum case_type this_type;
2159 int eqv = RE_TRANSLATE (eqv_table, start);
2160 int minchar, maxchar;
2161
2162 /* Classify this character */
2163 if (eqv == start)
2164 this_type = one_case;
2165 else if (RE_TRANSLATE (eqv_table, eqv) == start)
2166 this_type = two_case;
2167 else
2168 this_type = strange;
2169
2170 if (start < eqv)
2171 minchar = start, maxchar = eqv;
2172 else
2173 minchar = eqv, maxchar = start;
2174
2175 /* Can this character extend the run in progress? */
2176 if (this_type == strange || this_type != run_type
2177 || !(minchar == run_end + 1
2178 && (run_type == two_case
2179 ? maxchar == run_eqv_end + 1 : 1)))
2180 {
2181 /* No, end the run.
2182 Record each of its equivalent ranges. */
2183 if (run_type == one_case)
2184 {
2185 EXTEND_RANGE_TABLE (work_area, 2);
2186 work_area->table[work_area->used++] = run_start;
2187 work_area->table[work_area->used++] = run_end;
2188 }
2189 else if (run_type == two_case)
2190 {
2191 EXTEND_RANGE_TABLE (work_area, 4);
2192 work_area->table[work_area->used++] = run_start;
2193 work_area->table[work_area->used++] = run_end;
2194 work_area->table[work_area->used++]
2195 = RE_TRANSLATE (eqv_table, run_start);
2196 work_area->table[work_area->used++]
2197 = RE_TRANSLATE (eqv_table, run_end);
2198 }
2199 run_type = strange;
2200 }
2201
2202 if (this_type == strange)
2203 {
2204 /* For a strange character, add each of its equivalents, one
2205 by one. Don't start a range. */
2206 do
2207 {
2208 EXTEND_RANGE_TABLE (work_area, 2);
2209 work_area->table[work_area->used++] = eqv;
2210 work_area->table[work_area->used++] = eqv;
2211 eqv = RE_TRANSLATE (eqv_table, eqv);
2212 }
2213 while (eqv != start);
2214 }
2215
2216 /* Add this char to the run, or start a new run. */
2217 else if (run_type == strange)
2218 {
2219 /* Initialize a new range. */
2220 run_type = this_type;
2221 run_start = start;
2222 run_end = start;
2223 run_eqv_end = RE_TRANSLATE (eqv_table, run_end);
2224 }
2225 else
2226 {
2227 /* Extend a running range. */
2228 run_end = minchar;
2229 run_eqv_end = RE_TRANSLATE (eqv_table, run_end);
2230 }
2231 }
2232
2233 /* If a run is still in progress at the end, finish it now
2234 by recording its equivalent ranges. */
2235 if (run_type == one_case)
2236 {
2237 EXTEND_RANGE_TABLE (work_area, 2);
2238 work_area->table[work_area->used++] = run_start;
2239 work_area->table[work_area->used++] = run_end;
2240 }
2241 else if (run_type == two_case)
2242 {
2243 EXTEND_RANGE_TABLE (work_area, 4);
2244 work_area->table[work_area->used++] = run_start;
2245 work_area->table[work_area->used++] = run_end;
2246 work_area->table[work_area->used++]
2247 = RE_TRANSLATE (eqv_table, run_start);
2248 work_area->table[work_area->used++]
2249 = RE_TRANSLATE (eqv_table, run_end);
2250 }
2251
2252 return -1;
2253 }
2254
2255 #endif /* emacs */
2256
2257 /* Record the image of the range start..end when passed through
2258 TRANSLATE. This is not necessarily TRANSLATE(start)..TRANSLATE(end)
2259 and is not even necessarily contiguous.
2260 Normally we approximate it with the smallest contiguous range that contains
2261 all the chars we need. However, for Latin-1 we go to extra effort
2262 to do a better job.
2263
2264 This function is not called for ASCII ranges.
2265
2266 Returns -1 if successful, REG_ESPACE if ran out of space. */
2267
2268 static int
2269 set_image_of_range (struct range_table_work_area *work_area,
2270 re_wchar_t start, re_wchar_t end,
2271 RE_TRANSLATE_TYPE translate)
2272 {
2273 re_wchar_t cmin, cmax;
2274
2275 #ifdef emacs
2276 /* For Latin-1 ranges, use set_image_of_range_1
2277 to get proper handling of ranges that include letters and nonletters.
2278 For a range that includes the whole of Latin-1, this is not necessary.
2279 For other character sets, we don't bother to get this right. */
2280 if (RE_TRANSLATE_P (translate) && start < 04400
2281 && !(start < 04200 && end >= 04377))
2282 {
2283 int newend;
2284 int tem;
2285 newend = end;
2286 if (newend > 04377)
2287 newend = 04377;
2288 tem = set_image_of_range_1 (work_area, start, newend, translate);
2289 if (tem > 0)
2290 return tem;
2291
2292 start = 04400;
2293 if (end < 04400)
2294 return -1;
2295 }
2296 #endif
2297
2298 EXTEND_RANGE_TABLE (work_area, 2);
2299 work_area->table[work_area->used++] = (start);
2300 work_area->table[work_area->used++] = (end);
2301
2302 cmin = -1, cmax = -1;
2303
2304 if (RE_TRANSLATE_P (translate))
2305 {
2306 int ch;
2307
2308 for (ch = start; ch <= end; ch++)
2309 {
2310 re_wchar_t c = TRANSLATE (ch);
2311 if (! (start <= c && c <= end))
2312 {
2313 if (cmin == -1)
2314 cmin = c, cmax = c;
2315 else
2316 {
2317 cmin = MIN (cmin, c);
2318 cmax = MAX (cmax, c);
2319 }
2320 }
2321 }
2322
2323 if (cmin != -1)
2324 {
2325 EXTEND_RANGE_TABLE (work_area, 2);
2326 work_area->table[work_area->used++] = (cmin);
2327 work_area->table[work_area->used++] = (cmax);
2328 }
2329 }
2330
2331 return -1;
2332 }
2333 #endif /* 0 */
2334 \f
2335 #ifndef MATCH_MAY_ALLOCATE
2336
2337 /* If we cannot allocate large objects within re_match_2_internal,
2338 we make the fail stack and register vectors global.
2339 The fail stack, we grow to the maximum size when a regexp
2340 is compiled.
2341 The register vectors, we adjust in size each time we
2342 compile a regexp, according to the number of registers it needs. */
2343
2344 static fail_stack_type fail_stack;
2345
2346 /* Size with which the following vectors are currently allocated.
2347 That is so we can make them bigger as needed,
2348 but never make them smaller. */
2349 static int regs_allocated_size;
2350
2351 static re_char ** regstart, ** regend;
2352 static re_char **best_regstart, **best_regend;
2353
2354 /* Make the register vectors big enough for NUM_REGS registers,
2355 but don't make them smaller. */
2356
2357 static
2358 regex_grow_registers (int num_regs)
2359 {
2360 if (num_regs > regs_allocated_size)
2361 {
2362 RETALLOC_IF (regstart, num_regs, re_char *);
2363 RETALLOC_IF (regend, num_regs, re_char *);
2364 RETALLOC_IF (best_regstart, num_regs, re_char *);
2365 RETALLOC_IF (best_regend, num_regs, re_char *);
2366
2367 regs_allocated_size = num_regs;
2368 }
2369 }
2370
2371 #endif /* not MATCH_MAY_ALLOCATE */
2372 \f
2373 static boolean group_in_compile_stack (compile_stack_type compile_stack,
2374 regnum_t regnum);
2375
2376 /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
2377 Returns one of error codes defined in `regex.h', or zero for success.
2378
2379 Assumes the `allocated' (and perhaps `buffer') and `translate'
2380 fields are set in BUFP on entry.
2381
2382 If it succeeds, results are put in BUFP (if it returns an error, the
2383 contents of BUFP are undefined):
2384 `buffer' is the compiled pattern;
2385 `syntax' is set to SYNTAX;
2386 `used' is set to the length of the compiled pattern;
2387 `fastmap_accurate' is zero;
2388 `re_nsub' is the number of subexpressions in PATTERN;
2389 `not_bol' and `not_eol' are zero;
2390
2391 The `fastmap' field is neither examined nor set. */
2392
2393 /* Insert the `jump' from the end of last alternative to "here".
2394 The space for the jump has already been allocated. */
2395 #define FIXUP_ALT_JUMP() \
2396 do { \
2397 if (fixup_alt_jump) \
2398 STORE_JUMP (jump, fixup_alt_jump, b); \
2399 } while (0)
2400
2401
2402 /* Return, freeing storage we allocated. */
2403 #define FREE_STACK_RETURN(value) \
2404 do { \
2405 FREE_RANGE_TABLE_WORK_AREA (range_table_work); \
2406 free (compile_stack.stack); \
2407 return value; \
2408 } while (0)
2409
2410 static reg_errcode_t
2411 regex_compile (const_re_char *pattern, size_t size, reg_syntax_t syntax,
2412 struct re_pattern_buffer *bufp)
2413 {
2414 /* We fetch characters from PATTERN here. */
2415 register re_wchar_t c, c1;
2416
2417 /* Points to the end of the buffer, where we should append. */
2418 register unsigned char *b;
2419
2420 /* Keeps track of unclosed groups. */
2421 compile_stack_type compile_stack;
2422
2423 /* Points to the current (ending) position in the pattern. */
2424 #ifdef AIX
2425 /* `const' makes AIX compiler fail. */
2426 unsigned char *p = pattern;
2427 #else
2428 re_char *p = pattern;
2429 #endif
2430 re_char *pend = pattern + size;
2431
2432 /* How to translate the characters in the pattern. */
2433 RE_TRANSLATE_TYPE translate = bufp->translate;
2434
2435 /* Address of the count-byte of the most recently inserted `exactn'
2436 command. This makes it possible to tell if a new exact-match
2437 character can be added to that command or if the character requires
2438 a new `exactn' command. */
2439 unsigned char *pending_exact = 0;
2440
2441 /* Address of start of the most recently finished expression.
2442 This tells, e.g., postfix * where to find the start of its
2443 operand. Reset at the beginning of groups and alternatives. */
2444 unsigned char *laststart = 0;
2445
2446 /* Address of beginning of regexp, or inside of last group. */
2447 unsigned char *begalt;
2448
2449 /* Place in the uncompiled pattern (i.e., the {) to
2450 which to go back if the interval is invalid. */
2451 re_char *beg_interval;
2452
2453 /* Address of the place where a forward jump should go to the end of
2454 the containing expression. Each alternative of an `or' -- except the
2455 last -- ends with a forward jump of this sort. */
2456 unsigned char *fixup_alt_jump = 0;
2457
2458 /* Work area for range table of charset. */
2459 struct range_table_work_area range_table_work;
2460
2461 /* If the object matched can contain multibyte characters. */
2462 const boolean multibyte = RE_MULTIBYTE_P (bufp);
2463
2464 /* Nonzero if we have pushed down into a subpattern. */
2465 int in_subpattern = 0;
2466
2467 /* These hold the values of p, pattern, and pend from the main
2468 pattern when we have pushed into a subpattern. */
2469 re_char *main_p IF_LINT (= NULL);
2470 re_char *main_pattern IF_LINT (= NULL);
2471 re_char *main_pend IF_LINT (= NULL);
2472
2473 #ifdef DEBUG
2474 debug++;
2475 DEBUG_PRINT ("\nCompiling pattern: ");
2476 if (debug > 0)
2477 {
2478 unsigned debug_count;
2479
2480 for (debug_count = 0; debug_count < size; debug_count++)
2481 putchar (pattern[debug_count]);
2482 putchar ('\n');
2483 }
2484 #endif /* DEBUG */
2485
2486 /* Initialize the compile stack. */
2487 compile_stack.stack = TALLOC (INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
2488 if (compile_stack.stack == NULL)
2489 return REG_ESPACE;
2490
2491 compile_stack.size = INIT_COMPILE_STACK_SIZE;
2492 compile_stack.avail = 0;
2493
2494 range_table_work.table = 0;
2495 range_table_work.allocated = 0;
2496
2497 /* Initialize the pattern buffer. */
2498 bufp->syntax = syntax;
2499 bufp->fastmap_accurate = 0;
2500 bufp->not_bol = bufp->not_eol = 0;
2501 bufp->used_syntax = 0;
2502
2503 /* Set `used' to zero, so that if we return an error, the pattern
2504 printer (for debugging) will think there's no pattern. We reset it
2505 at the end. */
2506 bufp->used = 0;
2507
2508 /* Always count groups, whether or not bufp->no_sub is set. */
2509 bufp->re_nsub = 0;
2510
2511 #if !defined emacs && !defined SYNTAX_TABLE
2512 /* Initialize the syntax table. */
2513 init_syntax_once ();
2514 #endif
2515
2516 if (bufp->allocated == 0)
2517 {
2518 if (bufp->buffer)
2519 { /* If zero allocated, but buffer is non-null, try to realloc
2520 enough space. This loses if buffer's address is bogus, but
2521 that is the user's responsibility. */
2522 RETALLOC (bufp->buffer, INIT_BUF_SIZE, unsigned char);
2523 }
2524 else
2525 { /* Caller did not allocate a buffer. Do it for them. */
2526 bufp->buffer = TALLOC (INIT_BUF_SIZE, unsigned char);
2527 }
2528 if (!bufp->buffer) FREE_STACK_RETURN (REG_ESPACE);
2529
2530 bufp->allocated = INIT_BUF_SIZE;
2531 }
2532
2533 begalt = b = bufp->buffer;
2534
2535 /* Loop through the uncompiled pattern until we're at the end. */
2536 while (1)
2537 {
2538 if (p == pend)
2539 {
2540 /* If this is the end of an included regexp,
2541 pop back to the main regexp and try again. */
2542 if (in_subpattern)
2543 {
2544 in_subpattern = 0;
2545 pattern = main_pattern;
2546 p = main_p;
2547 pend = main_pend;
2548 continue;
2549 }
2550 /* If this is the end of the main regexp, we are done. */
2551 break;
2552 }
2553
2554 PATFETCH (c);
2555
2556 switch (c)
2557 {
2558 case ' ':
2559 {
2560 re_char *p1 = p;
2561
2562 /* If there's no special whitespace regexp, treat
2563 spaces normally. And don't try to do this recursively. */
2564 if (!whitespace_regexp || in_subpattern)
2565 goto normal_char;
2566
2567 /* Peek past following spaces. */
2568 while (p1 != pend)
2569 {
2570 if (*p1 != ' ')
2571 break;
2572 p1++;
2573 }
2574 /* If the spaces are followed by a repetition op,
2575 treat them normally. */
2576 if (p1 != pend
2577 && (*p1 == '*' || *p1 == '+' || *p1 == '?'
2578 || (*p1 == '\\' && p1 + 1 != pend && p1[1] == '{')))
2579 goto normal_char;
2580
2581 /* Replace the spaces with the whitespace regexp. */
2582 in_subpattern = 1;
2583 main_p = p1;
2584 main_pend = pend;
2585 main_pattern = pattern;
2586 p = pattern = whitespace_regexp;
2587 pend = p + strlen ((const char *) p);
2588 break;
2589 }
2590
2591 case '^':
2592 {
2593 if ( /* If at start of pattern, it's an operator. */
2594 p == pattern + 1
2595 /* If context independent, it's an operator. */
2596 || syntax & RE_CONTEXT_INDEP_ANCHORS
2597 /* Otherwise, depends on what's come before. */
2598 || at_begline_loc_p (pattern, p, syntax))
2599 BUF_PUSH ((syntax & RE_NO_NEWLINE_ANCHOR) ? begbuf : begline);
2600 else
2601 goto normal_char;
2602 }
2603 break;
2604
2605
2606 case '$':
2607 {
2608 if ( /* If at end of pattern, it's an operator. */
2609 p == pend
2610 /* If context independent, it's an operator. */
2611 || syntax & RE_CONTEXT_INDEP_ANCHORS
2612 /* Otherwise, depends on what's next. */
2613 || at_endline_loc_p (p, pend, syntax))
2614 BUF_PUSH ((syntax & RE_NO_NEWLINE_ANCHOR) ? endbuf : endline);
2615 else
2616 goto normal_char;
2617 }
2618 break;
2619
2620
2621 case '+':
2622 case '?':
2623 if ((syntax & RE_BK_PLUS_QM)
2624 || (syntax & RE_LIMITED_OPS))
2625 goto normal_char;
2626 handle_plus:
2627 case '*':
2628 /* If there is no previous pattern... */
2629 if (!laststart)
2630 {
2631 if (syntax & RE_CONTEXT_INVALID_OPS)
2632 FREE_STACK_RETURN (REG_BADRPT);
2633 else if (!(syntax & RE_CONTEXT_INDEP_OPS))
2634 goto normal_char;
2635 }
2636
2637 {
2638 /* 1 means zero (many) matches is allowed. */
2639 boolean zero_times_ok = 0, many_times_ok = 0;
2640 boolean greedy = 1;
2641
2642 /* If there is a sequence of repetition chars, collapse it
2643 down to just one (the right one). We can't combine
2644 interval operators with these because of, e.g., `a{2}*',
2645 which should only match an even number of `a's. */
2646
2647 for (;;)
2648 {
2649 if ((syntax & RE_FRUGAL)
2650 && c == '?' && (zero_times_ok || many_times_ok))
2651 greedy = 0;
2652 else
2653 {
2654 zero_times_ok |= c != '+';
2655 many_times_ok |= c != '?';
2656 }
2657
2658 if (p == pend)
2659 break;
2660 else if (*p == '*'
2661 || (!(syntax & RE_BK_PLUS_QM)
2662 && (*p == '+' || *p == '?')))
2663 ;
2664 else if (syntax & RE_BK_PLUS_QM && *p == '\\')
2665 {
2666 if (p+1 == pend)
2667 FREE_STACK_RETURN (REG_EESCAPE);
2668 if (p[1] == '+' || p[1] == '?')
2669 PATFETCH (c); /* Gobble up the backslash. */
2670 else
2671 break;
2672 }
2673 else
2674 break;
2675 /* If we get here, we found another repeat character. */
2676 PATFETCH (c);
2677 }
2678
2679 /* Star, etc. applied to an empty pattern is equivalent
2680 to an empty pattern. */
2681 if (!laststart || laststart == b)
2682 break;
2683
2684 /* Now we know whether or not zero matches is allowed
2685 and also whether or not two or more matches is allowed. */
2686 if (greedy)
2687 {
2688 if (many_times_ok)
2689 {
2690 boolean simple = skip_one_char (laststart) == b;
2691 size_t startoffset = 0;
2692 re_opcode_t ofj =
2693 /* Check if the loop can match the empty string. */
2694 (simple || !analyse_first (laststart, b, NULL, 0))
2695 ? on_failure_jump : on_failure_jump_loop;
2696 assert (skip_one_char (laststart) <= b);
2697
2698 if (!zero_times_ok && simple)
2699 { /* Since simple * loops can be made faster by using
2700 on_failure_keep_string_jump, we turn simple P+
2701 into PP* if P is simple. */
2702 unsigned char *p1, *p2;
2703 startoffset = b - laststart;
2704 GET_BUFFER_SPACE (startoffset);
2705 p1 = b; p2 = laststart;
2706 while (p2 < p1)
2707 *b++ = *p2++;
2708 zero_times_ok = 1;
2709 }
2710
2711 GET_BUFFER_SPACE (6);
2712 if (!zero_times_ok)
2713 /* A + loop. */
2714 STORE_JUMP (ofj, b, b + 6);
2715 else
2716 /* Simple * loops can use on_failure_keep_string_jump
2717 depending on what follows. But since we don't know
2718 that yet, we leave the decision up to
2719 on_failure_jump_smart. */
2720 INSERT_JUMP (simple ? on_failure_jump_smart : ofj,
2721 laststart + startoffset, b + 6);
2722 b += 3;
2723 STORE_JUMP (jump, b, laststart + startoffset);
2724 b += 3;
2725 }
2726 else
2727 {
2728 /* A simple ? pattern. */
2729 assert (zero_times_ok);
2730 GET_BUFFER_SPACE (3);
2731 INSERT_JUMP (on_failure_jump, laststart, b + 3);
2732 b += 3;
2733 }
2734 }
2735 else /* not greedy */
2736 { /* I wish the greedy and non-greedy cases could be merged. */
2737
2738 GET_BUFFER_SPACE (7); /* We might use less. */
2739 if (many_times_ok)
2740 {
2741 boolean emptyp = analyse_first (laststart, b, NULL, 0);
2742
2743 /* The non-greedy multiple match looks like
2744 a repeat..until: we only need a conditional jump
2745 at the end of the loop. */
2746 if (emptyp) BUF_PUSH (no_op);
2747 STORE_JUMP (emptyp ? on_failure_jump_nastyloop
2748 : on_failure_jump, b, laststart);
2749 b += 3;
2750 if (zero_times_ok)
2751 {
2752 /* The repeat...until naturally matches one or more.
2753 To also match zero times, we need to first jump to
2754 the end of the loop (its conditional jump). */
2755 INSERT_JUMP (jump, laststart, b);
2756 b += 3;
2757 }
2758 }
2759 else
2760 {
2761 /* non-greedy a?? */
2762 INSERT_JUMP (jump, laststart, b + 3);
2763 b += 3;
2764 INSERT_JUMP (on_failure_jump, laststart, laststart + 6);
2765 b += 3;
2766 }
2767 }
2768 }
2769 pending_exact = 0;
2770 break;
2771
2772
2773 case '.':
2774 laststart = b;
2775 BUF_PUSH (anychar);
2776 break;
2777
2778
2779 case '[':
2780 {
2781 re_char *p1;
2782
2783 CLEAR_RANGE_TABLE_WORK_USED (range_table_work);
2784
2785 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2786
2787 /* Ensure that we have enough space to push a charset: the
2788 opcode, the length count, and the bitset; 34 bytes in all. */
2789 GET_BUFFER_SPACE (34);
2790
2791 laststart = b;
2792
2793 /* We test `*p == '^' twice, instead of using an if
2794 statement, so we only need one BUF_PUSH. */
2795 BUF_PUSH (*p == '^' ? charset_not : charset);
2796 if (*p == '^')
2797 p++;
2798
2799 /* Remember the first position in the bracket expression. */
2800 p1 = p;
2801
2802 /* Push the number of bytes in the bitmap. */
2803 BUF_PUSH ((1 << BYTEWIDTH) / BYTEWIDTH);
2804
2805 /* Clear the whole map. */
2806 memset (b, 0, (1 << BYTEWIDTH) / BYTEWIDTH);
2807
2808 /* charset_not matches newline according to a syntax bit. */
2809 if ((re_opcode_t) b[-2] == charset_not
2810 && (syntax & RE_HAT_LISTS_NOT_NEWLINE))
2811 SET_LIST_BIT ('\n');
2812
2813 /* Read in characters and ranges, setting map bits. */
2814 for (;;)
2815 {
2816 boolean escaped_char = false;
2817 const unsigned char *p2 = p;
2818 re_wchar_t ch;
2819
2820 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2821
2822 /* Don't translate yet. The range TRANSLATE(X..Y) cannot
2823 always be determined from TRANSLATE(X) and TRANSLATE(Y)
2824 So the translation is done later in a loop. Example:
2825 (let ((case-fold-search t)) (string-match "[A-_]" "A")) */
2826 PATFETCH (c);
2827
2828 /* \ might escape characters inside [...] and [^...]. */
2829 if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\')
2830 {
2831 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2832
2833 PATFETCH (c);
2834 escaped_char = true;
2835 }
2836 else
2837 {
2838 /* Could be the end of the bracket expression. If it's
2839 not (i.e., when the bracket expression is `[]' so
2840 far), the ']' character bit gets set way below. */
2841 if (c == ']' && p2 != p1)
2842 break;
2843 }
2844
2845 /* See if we're at the beginning of a possible character
2846 class. */
2847
2848 if (!escaped_char &&
2849 syntax & RE_CHAR_CLASSES && c == '[' && *p == ':')
2850 {
2851 /* Leave room for the null. */
2852 unsigned char str[CHAR_CLASS_MAX_LENGTH + 1];
2853 const unsigned char *class_beg;
2854
2855 PATFETCH (c);
2856 c1 = 0;
2857 class_beg = p;
2858
2859 /* If pattern is `[[:'. */
2860 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2861
2862 for (;;)
2863 {
2864 PATFETCH (c);
2865 if ((c == ':' && *p == ']') || p == pend)
2866 break;
2867 if (c1 < CHAR_CLASS_MAX_LENGTH)
2868 str[c1++] = c;
2869 else
2870 /* This is in any case an invalid class name. */
2871 str[0] = '\0';
2872 }
2873 str[c1] = '\0';
2874
2875 /* If isn't a word bracketed by `[:' and `:]':
2876 undo the ending character, the letters, and
2877 leave the leading `:' and `[' (but set bits for
2878 them). */
2879 if (c == ':' && *p == ']')
2880 {
2881 re_wctype_t cc = re_wctype (str);
2882
2883 if (cc == 0)
2884 FREE_STACK_RETURN (REG_ECTYPE);
2885
2886 /* Throw away the ] at the end of the character
2887 class. */
2888 PATFETCH (c);
2889
2890 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2891
2892 #ifndef emacs
2893 for (ch = 0; ch < (1 << BYTEWIDTH); ++ch)
2894 if (re_iswctype (btowc (ch), cc))
2895 {
2896 c = TRANSLATE (ch);
2897 if (c < (1 << BYTEWIDTH))
2898 SET_LIST_BIT (c);
2899 }
2900 #else /* emacs */
2901 /* Most character classes in a multibyte match
2902 just set a flag. Exceptions are is_blank,
2903 is_digit, is_cntrl, and is_xdigit, since
2904 they can only match ASCII characters. We
2905 don't need to handle them for multibyte.
2906 They are distinguished by a negative wctype. */
2907
2908 /* Setup the gl_state object to its buffer-defined
2909 value. This hardcodes the buffer-global
2910 syntax-table for ASCII chars, while the other chars
2911 will obey syntax-table properties. It's not ideal,
2912 but it's the way it's been done until now. */
2913 SETUP_BUFFER_SYNTAX_TABLE ();
2914
2915 for (ch = 0; ch < 256; ++ch)
2916 {
2917 c = RE_CHAR_TO_MULTIBYTE (ch);
2918 if (! CHAR_BYTE8_P (c)
2919 && re_iswctype (c, cc))
2920 {
2921 SET_LIST_BIT (ch);
2922 c1 = TRANSLATE (c);
2923 if (c1 == c)
2924 continue;
2925 if (ASCII_CHAR_P (c1))
2926 SET_LIST_BIT (c1);
2927 else if ((c1 = RE_CHAR_TO_UNIBYTE (c1)) >= 0)
2928 SET_LIST_BIT (c1);
2929 }
2930 }
2931 SET_RANGE_TABLE_WORK_AREA_BIT
2932 (range_table_work, re_wctype_to_bit (cc));
2933 #endif /* emacs */
2934 /* In most cases the matching rule for char classes
2935 only uses the syntax table for multibyte chars,
2936 so that the content of the syntax-table it is not
2937 hardcoded in the range_table. SPACE and WORD are
2938 the two exceptions. */
2939 if ((1 << cc) & ((1 << RECC_SPACE) | (1 << RECC_WORD)))
2940 bufp->used_syntax = 1;
2941
2942 /* Repeat the loop. */
2943 continue;
2944 }
2945 else
2946 {
2947 /* Go back to right after the "[:". */
2948 p = class_beg;
2949 SET_LIST_BIT ('[');
2950
2951 /* Because the `:' may starts the range, we
2952 can't simply set bit and repeat the loop.
2953 Instead, just set it to C and handle below. */
2954 c = ':';
2955 }
2956 }
2957
2958 if (p < pend && p[0] == '-' && p[1] != ']')
2959 {
2960
2961 /* Discard the `-'. */
2962 PATFETCH (c1);
2963
2964 /* Fetch the character which ends the range. */
2965 PATFETCH (c1);
2966 #ifdef emacs
2967 if (CHAR_BYTE8_P (c1)
2968 && ! ASCII_CHAR_P (c) && ! CHAR_BYTE8_P (c))
2969 /* Treat the range from a multibyte character to
2970 raw-byte character as empty. */
2971 c = c1 + 1;
2972 #endif /* emacs */
2973 }
2974 else
2975 /* Range from C to C. */
2976 c1 = c;
2977
2978 if (c > c1)
2979 {
2980 if (syntax & RE_NO_EMPTY_RANGES)
2981 FREE_STACK_RETURN (REG_ERANGEX);
2982 /* Else, repeat the loop. */
2983 }
2984 else
2985 {
2986 #ifndef emacs
2987 /* Set the range into bitmap */
2988 for (; c <= c1; c++)
2989 {
2990 ch = TRANSLATE (c);
2991 if (ch < (1 << BYTEWIDTH))
2992 SET_LIST_BIT (ch);
2993 }
2994 #else /* emacs */
2995 if (c < 128)
2996 {
2997 ch = MIN (127, c1);
2998 SETUP_ASCII_RANGE (range_table_work, c, ch);
2999 c = ch + 1;
3000 if (CHAR_BYTE8_P (c1))
3001 c = BYTE8_TO_CHAR (128);
3002 }
3003 if (c <= c1)
3004 {
3005 if (CHAR_BYTE8_P (c))
3006 {
3007 c = CHAR_TO_BYTE8 (c);
3008 c1 = CHAR_TO_BYTE8 (c1);
3009 for (; c <= c1; c++)
3010 SET_LIST_BIT (c);
3011 }
3012 else if (multibyte)
3013 {
3014 SETUP_MULTIBYTE_RANGE (range_table_work, c, c1);
3015 }
3016 else
3017 {
3018 SETUP_UNIBYTE_RANGE (range_table_work, c, c1);
3019 }
3020 }
3021 #endif /* emacs */
3022 }
3023 }
3024
3025 /* Discard any (non)matching list bytes that are all 0 at the
3026 end of the map. Decrease the map-length byte too. */
3027 while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
3028 b[-1]--;
3029 b += b[-1];
3030
3031 /* Build real range table from work area. */
3032 if (RANGE_TABLE_WORK_USED (range_table_work)
3033 || RANGE_TABLE_WORK_BITS (range_table_work))
3034 {
3035 int i;
3036 int used = RANGE_TABLE_WORK_USED (range_table_work);
3037
3038 /* Allocate space for COUNT + RANGE_TABLE. Needs two
3039 bytes for flags, two for COUNT, and three bytes for
3040 each character. */
3041 GET_BUFFER_SPACE (4 + used * 3);
3042
3043 /* Indicate the existence of range table. */
3044 laststart[1] |= 0x80;
3045
3046 /* Store the character class flag bits into the range table.
3047 If not in emacs, these flag bits are always 0. */
3048 *b++ = RANGE_TABLE_WORK_BITS (range_table_work) & 0xff;
3049 *b++ = RANGE_TABLE_WORK_BITS (range_table_work) >> 8;
3050
3051 STORE_NUMBER_AND_INCR (b, used / 2);
3052 for (i = 0; i < used; i++)
3053 STORE_CHARACTER_AND_INCR
3054 (b, RANGE_TABLE_WORK_ELT (range_table_work, i));
3055 }
3056 }
3057 break;
3058
3059
3060 case '(':
3061 if (syntax & RE_NO_BK_PARENS)
3062 goto handle_open;
3063 else
3064 goto normal_char;
3065
3066
3067 case ')':
3068 if (syntax & RE_NO_BK_PARENS)
3069 goto handle_close;
3070 else
3071 goto normal_char;
3072
3073
3074 case '\n':
3075 if (syntax & RE_NEWLINE_ALT)
3076 goto handle_alt;
3077 else
3078 goto normal_char;
3079
3080
3081 case '|':
3082 if (syntax & RE_NO_BK_VBAR)
3083 goto handle_alt;
3084 else
3085 goto normal_char;
3086
3087
3088 case '{':
3089 if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
3090 goto handle_interval;
3091 else
3092 goto normal_char;
3093
3094
3095 case '\\':
3096 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
3097
3098 /* Do not translate the character after the \, so that we can
3099 distinguish, e.g., \B from \b, even if we normally would
3100 translate, e.g., B to b. */
3101 PATFETCH (c);
3102
3103 switch (c)
3104 {
3105 case '(':
3106 if (syntax & RE_NO_BK_PARENS)
3107 goto normal_backslash;
3108
3109 handle_open:
3110 {
3111 int shy = 0;
3112 regnum_t regnum = 0;
3113 if (p+1 < pend)
3114 {
3115 /* Look for a special (?...) construct */
3116 if ((syntax & RE_SHY_GROUPS) && *p == '?')
3117 {
3118 PATFETCH (c); /* Gobble up the '?'. */
3119 while (!shy)
3120 {
3121 PATFETCH (c);
3122 switch (c)
3123 {
3124 case ':': shy = 1; break;
3125 case '0':
3126 /* An explicitly specified regnum must start
3127 with non-0. */
3128 if (regnum == 0)
3129 FREE_STACK_RETURN (REG_BADPAT);
3130 case '1': case '2': case '3': case '4':
3131 case '5': case '6': case '7': case '8': case '9':
3132 regnum = 10*regnum + (c - '0'); break;
3133 default:
3134 /* Only (?:...) is supported right now. */
3135 FREE_STACK_RETURN (REG_BADPAT);
3136 }
3137 }
3138 }
3139 }
3140
3141 if (!shy)
3142 regnum = ++bufp->re_nsub;
3143 else if (regnum)
3144 { /* It's actually not shy, but explicitly numbered. */
3145 shy = 0;
3146 if (regnum > bufp->re_nsub)
3147 bufp->re_nsub = regnum;
3148 else if (regnum > bufp->re_nsub
3149 /* Ideally, we'd want to check that the specified
3150 group can't have matched (i.e. all subgroups
3151 using the same regnum are in other branches of
3152 OR patterns), but we don't currently keep track
3153 of enough info to do that easily. */
3154 || group_in_compile_stack (compile_stack, regnum))
3155 FREE_STACK_RETURN (REG_BADPAT);
3156 }
3157 else
3158 /* It's really shy. */
3159 regnum = - bufp->re_nsub;
3160
3161 if (COMPILE_STACK_FULL)
3162 {
3163 RETALLOC (compile_stack.stack, compile_stack.size << 1,
3164 compile_stack_elt_t);
3165 if (compile_stack.stack == NULL) return REG_ESPACE;
3166
3167 compile_stack.size <<= 1;
3168 }
3169
3170 /* These are the values to restore when we hit end of this
3171 group. They are all relative offsets, so that if the
3172 whole pattern moves because of realloc, they will still
3173 be valid. */
3174 COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
3175 COMPILE_STACK_TOP.fixup_alt_jump
3176 = fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
3177 COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
3178 COMPILE_STACK_TOP.regnum = regnum;
3179
3180 /* Do not push a start_memory for groups beyond the last one
3181 we can represent in the compiled pattern. */
3182 if (regnum <= MAX_REGNUM && regnum > 0)
3183 BUF_PUSH_2 (start_memory, regnum);
3184
3185 compile_stack.avail++;
3186
3187 fixup_alt_jump = 0;
3188 laststart = 0;
3189 begalt = b;
3190 /* If we've reached MAX_REGNUM groups, then this open
3191 won't actually generate any code, so we'll have to
3192 clear pending_exact explicitly. */
3193 pending_exact = 0;
3194 break;
3195 }
3196
3197 case ')':
3198 if (syntax & RE_NO_BK_PARENS) goto normal_backslash;
3199
3200 if (COMPILE_STACK_EMPTY)
3201 {
3202 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
3203 goto normal_backslash;
3204 else
3205 FREE_STACK_RETURN (REG_ERPAREN);
3206 }
3207
3208 handle_close:
3209 FIXUP_ALT_JUMP ();
3210
3211 /* See similar code for backslashed left paren above. */
3212 if (COMPILE_STACK_EMPTY)
3213 {
3214 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
3215 goto normal_char;
3216 else
3217 FREE_STACK_RETURN (REG_ERPAREN);
3218 }
3219
3220 /* Since we just checked for an empty stack above, this
3221 ``can't happen''. */
3222 assert (compile_stack.avail != 0);
3223 {
3224 /* We don't just want to restore into `regnum', because
3225 later groups should continue to be numbered higher,
3226 as in `(ab)c(de)' -- the second group is #2. */
3227 regnum_t regnum;
3228
3229 compile_stack.avail--;
3230 begalt = bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
3231 fixup_alt_jump
3232 = COMPILE_STACK_TOP.fixup_alt_jump
3233 ? bufp->buffer + COMPILE_STACK_TOP.fixup_alt_jump - 1
3234 : 0;
3235 laststart = bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
3236 regnum = COMPILE_STACK_TOP.regnum;
3237 /* If we've reached MAX_REGNUM groups, then this open
3238 won't actually generate any code, so we'll have to
3239 clear pending_exact explicitly. */
3240 pending_exact = 0;
3241
3242 /* We're at the end of the group, so now we know how many
3243 groups were inside this one. */
3244 if (regnum <= MAX_REGNUM && regnum > 0)
3245 BUF_PUSH_2 (stop_memory, regnum);
3246 }
3247 break;
3248
3249
3250 case '|': /* `\|'. */
3251 if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
3252 goto normal_backslash;
3253 handle_alt:
3254 if (syntax & RE_LIMITED_OPS)
3255 goto normal_char;
3256
3257 /* Insert before the previous alternative a jump which
3258 jumps to this alternative if the former fails. */
3259 GET_BUFFER_SPACE (3);
3260 INSERT_JUMP (on_failure_jump, begalt, b + 6);
3261 pending_exact = 0;
3262 b += 3;
3263
3264 /* The alternative before this one has a jump after it
3265 which gets executed if it gets matched. Adjust that
3266 jump so it will jump to this alternative's analogous
3267 jump (put in below, which in turn will jump to the next
3268 (if any) alternative's such jump, etc.). The last such
3269 jump jumps to the correct final destination. A picture:
3270 _____ _____
3271 | | | |
3272 | v | v
3273 a | b | c
3274
3275 If we are at `b', then fixup_alt_jump right now points to a
3276 three-byte space after `a'. We'll put in the jump, set
3277 fixup_alt_jump to right after `b', and leave behind three
3278 bytes which we'll fill in when we get to after `c'. */
3279
3280 FIXUP_ALT_JUMP ();
3281
3282 /* Mark and leave space for a jump after this alternative,
3283 to be filled in later either by next alternative or
3284 when know we're at the end of a series of alternatives. */
3285 fixup_alt_jump = b;
3286 GET_BUFFER_SPACE (3);
3287 b += 3;
3288
3289 laststart = 0;
3290 begalt = b;
3291 break;
3292
3293
3294 case '{':
3295 /* If \{ is a literal. */
3296 if (!(syntax & RE_INTERVALS)
3297 /* If we're at `\{' and it's not the open-interval
3298 operator. */
3299 || (syntax & RE_NO_BK_BRACES))
3300 goto normal_backslash;
3301
3302 handle_interval:
3303 {
3304 /* If got here, then the syntax allows intervals. */
3305
3306 /* At least (most) this many matches must be made. */
3307 int lower_bound = 0, upper_bound = -1;
3308
3309 beg_interval = p;
3310
3311 GET_INTERVAL_COUNT (lower_bound);
3312
3313 if (c == ',')
3314 GET_INTERVAL_COUNT (upper_bound);
3315 else
3316 /* Interval such as `{1}' => match exactly once. */
3317 upper_bound = lower_bound;
3318
3319 if (lower_bound < 0
3320 || (0 <= upper_bound && upper_bound < lower_bound))
3321 FREE_STACK_RETURN (REG_BADBR);
3322
3323 if (!(syntax & RE_NO_BK_BRACES))
3324 {
3325 if (c != '\\')
3326 FREE_STACK_RETURN (REG_BADBR);
3327 if (p == pend)
3328 FREE_STACK_RETURN (REG_EESCAPE);
3329 PATFETCH (c);
3330 }
3331
3332 if (c != '}')
3333 FREE_STACK_RETURN (REG_BADBR);
3334
3335 /* We just parsed a valid interval. */
3336
3337 /* If it's invalid to have no preceding re. */
3338 if (!laststart)
3339 {
3340 if (syntax & RE_CONTEXT_INVALID_OPS)
3341 FREE_STACK_RETURN (REG_BADRPT);
3342 else if (syntax & RE_CONTEXT_INDEP_OPS)
3343 laststart = b;
3344 else
3345 goto unfetch_interval;
3346 }
3347
3348 if (upper_bound == 0)
3349 /* If the upper bound is zero, just drop the sub pattern
3350 altogether. */
3351 b = laststart;
3352 else if (lower_bound == 1 && upper_bound == 1)
3353 /* Just match it once: nothing to do here. */
3354 ;
3355
3356 /* Otherwise, we have a nontrivial interval. When
3357 we're all done, the pattern will look like:
3358 set_number_at <jump count> <upper bound>
3359 set_number_at <succeed_n count> <lower bound>
3360 succeed_n <after jump addr> <succeed_n count>
3361 <body of loop>
3362 jump_n <succeed_n addr> <jump count>
3363 (The upper bound and `jump_n' are omitted if
3364 `upper_bound' is 1, though.) */
3365 else
3366 { /* If the upper bound is > 1, we need to insert
3367 more at the end of the loop. */
3368 unsigned int nbytes = (upper_bound < 0 ? 3
3369 : upper_bound > 1 ? 5 : 0);
3370 unsigned int startoffset = 0;
3371
3372 GET_BUFFER_SPACE (20); /* We might use less. */
3373
3374 if (lower_bound == 0)
3375 {
3376 /* A succeed_n that starts with 0 is really a
3377 a simple on_failure_jump_loop. */
3378 INSERT_JUMP (on_failure_jump_loop, laststart,
3379 b + 3 + nbytes);
3380 b += 3;
3381 }
3382 else
3383 {
3384 /* Initialize lower bound of the `succeed_n', even
3385 though it will be set during matching by its
3386 attendant `set_number_at' (inserted next),
3387 because `re_compile_fastmap' needs to know.
3388 Jump to the `jump_n' we might insert below. */
3389 INSERT_JUMP2 (succeed_n, laststart,
3390 b + 5 + nbytes,
3391 lower_bound);
3392 b += 5;
3393
3394 /* Code to initialize the lower bound. Insert
3395 before the `succeed_n'. The `5' is the last two
3396 bytes of this `set_number_at', plus 3 bytes of
3397 the following `succeed_n'. */
3398 insert_op2 (set_number_at, laststart, 5, lower_bound, b);
3399 b += 5;
3400 startoffset += 5;
3401 }
3402
3403 if (upper_bound < 0)
3404 {
3405 /* A negative upper bound stands for infinity,
3406 in which case it degenerates to a plain jump. */
3407 STORE_JUMP (jump, b, laststart + startoffset);
3408 b += 3;
3409 }
3410 else if (upper_bound > 1)
3411 { /* More than one repetition is allowed, so
3412 append a backward jump to the `succeed_n'
3413 that starts this interval.
3414
3415 When we've reached this during matching,
3416 we'll have matched the interval once, so
3417 jump back only `upper_bound - 1' times. */
3418 STORE_JUMP2 (jump_n, b, laststart + startoffset,
3419 upper_bound - 1);
3420 b += 5;
3421
3422 /* The location we want to set is the second
3423 parameter of the `jump_n'; that is `b-2' as
3424 an absolute address. `laststart' will be
3425 the `set_number_at' we're about to insert;
3426 `laststart+3' the number to set, the source
3427 for the relative address. But we are
3428 inserting into the middle of the pattern --
3429 so everything is getting moved up by 5.
3430 Conclusion: (b - 2) - (laststart + 3) + 5,
3431 i.e., b - laststart.
3432
3433 We insert this at the beginning of the loop
3434 so that if we fail during matching, we'll
3435 reinitialize the bounds. */
3436 insert_op2 (set_number_at, laststart, b - laststart,
3437 upper_bound - 1, b);
3438 b += 5;
3439 }
3440 }
3441 pending_exact = 0;
3442 beg_interval = NULL;
3443 }
3444 break;
3445
3446 unfetch_interval:
3447 /* If an invalid interval, match the characters as literals. */
3448 assert (beg_interval);
3449 p = beg_interval;
3450 beg_interval = NULL;
3451
3452 /* normal_char and normal_backslash need `c'. */
3453 c = '{';
3454
3455 if (!(syntax & RE_NO_BK_BRACES))
3456 {
3457 assert (p > pattern && p[-1] == '\\');
3458 goto normal_backslash;
3459 }
3460 else
3461 goto normal_char;
3462
3463 #ifdef emacs
3464 /* There is no way to specify the before_dot and after_dot
3465 operators. rms says this is ok. --karl */
3466 case '=':
3467 laststart = b;
3468 BUF_PUSH (at_dot);
3469 break;
3470
3471 case 's':
3472 laststart = b;
3473 PATFETCH (c);
3474 BUF_PUSH_2 (syntaxspec, syntax_spec_code[c]);
3475 break;
3476
3477 case 'S':
3478 laststart = b;
3479 PATFETCH (c);
3480 BUF_PUSH_2 (notsyntaxspec, syntax_spec_code[c]);
3481 break;
3482
3483 case 'c':
3484 laststart = b;
3485 PATFETCH (c);
3486 BUF_PUSH_2 (categoryspec, c);
3487 break;
3488
3489 case 'C':
3490 laststart = b;
3491 PATFETCH (c);
3492 BUF_PUSH_2 (notcategoryspec, c);
3493 break;
3494 #endif /* emacs */
3495
3496
3497 case 'w':
3498 if (syntax & RE_NO_GNU_OPS)
3499 goto normal_char;
3500 laststart = b;
3501 BUF_PUSH_2 (syntaxspec, Sword);
3502 break;
3503
3504
3505 case 'W':
3506 if (syntax & RE_NO_GNU_OPS)
3507 goto normal_char;
3508 laststart = b;
3509 BUF_PUSH_2 (notsyntaxspec, Sword);
3510 break;
3511
3512
3513 case '<':
3514 if (syntax & RE_NO_GNU_OPS)
3515 goto normal_char;
3516 laststart = b;
3517 BUF_PUSH (wordbeg);
3518 break;
3519
3520 case '>':
3521 if (syntax & RE_NO_GNU_OPS)
3522 goto normal_char;
3523 laststart = b;
3524 BUF_PUSH (wordend);
3525 break;
3526
3527 case '_':
3528 if (syntax & RE_NO_GNU_OPS)
3529 goto normal_char;
3530 laststart = b;
3531 PATFETCH (c);
3532 if (c == '<')
3533 BUF_PUSH (symbeg);
3534 else if (c == '>')
3535 BUF_PUSH (symend);
3536 else
3537 FREE_STACK_RETURN (REG_BADPAT);
3538 break;
3539
3540 case 'b':
3541 if (syntax & RE_NO_GNU_OPS)
3542 goto normal_char;
3543 BUF_PUSH (wordbound);
3544 break;
3545
3546 case 'B':
3547 if (syntax & RE_NO_GNU_OPS)
3548 goto normal_char;
3549 BUF_PUSH (notwordbound);
3550 break;
3551
3552 case '`':
3553 if (syntax & RE_NO_GNU_OPS)
3554 goto normal_char;
3555 BUF_PUSH (begbuf);
3556 break;
3557
3558 case '\'':
3559 if (syntax & RE_NO_GNU_OPS)
3560 goto normal_char;
3561 BUF_PUSH (endbuf);
3562 break;
3563
3564 case '1': case '2': case '3': case '4': case '5':
3565 case '6': case '7': case '8': case '9':
3566 {
3567 regnum_t reg;
3568
3569 if (syntax & RE_NO_BK_REFS)
3570 goto normal_backslash;
3571
3572 reg = c - '0';
3573
3574 if (reg > bufp->re_nsub || reg < 1
3575 /* Can't back reference to a subexp before its end. */
3576 || group_in_compile_stack (compile_stack, reg))
3577 FREE_STACK_RETURN (REG_ESUBREG);
3578
3579 laststart = b;
3580 BUF_PUSH_2 (duplicate, reg);
3581 }
3582 break;
3583
3584
3585 case '+':
3586 case '?':
3587 if (syntax & RE_BK_PLUS_QM)
3588 goto handle_plus;
3589 else
3590 goto normal_backslash;
3591
3592 default:
3593 normal_backslash:
3594 /* You might think it would be useful for \ to mean
3595 not to translate; but if we don't translate it
3596 it will never match anything. */
3597 goto normal_char;
3598 }
3599 break;
3600
3601
3602 default:
3603 /* Expects the character in `c'. */
3604 normal_char:
3605 /* If no exactn currently being built. */
3606 if (!pending_exact
3607
3608 /* If last exactn not at current position. */
3609 || pending_exact + *pending_exact + 1 != b
3610
3611 /* We have only one byte following the exactn for the count. */
3612 || *pending_exact >= (1 << BYTEWIDTH) - MAX_MULTIBYTE_LENGTH
3613
3614 /* If followed by a repetition operator. */
3615 || (p != pend && (*p == '*' || *p == '^'))
3616 || ((syntax & RE_BK_PLUS_QM)
3617 ? p + 1 < pend && *p == '\\' && (p[1] == '+' || p[1] == '?')
3618 : p != pend && (*p == '+' || *p == '?'))
3619 || ((syntax & RE_INTERVALS)
3620 && ((syntax & RE_NO_BK_BRACES)
3621 ? p != pend && *p == '{'
3622 : p + 1 < pend && p[0] == '\\' && p[1] == '{')))
3623 {
3624 /* Start building a new exactn. */
3625
3626 laststart = b;
3627
3628 BUF_PUSH_2 (exactn, 0);
3629 pending_exact = b - 1;
3630 }
3631
3632 GET_BUFFER_SPACE (MAX_MULTIBYTE_LENGTH);
3633 {
3634 int len;
3635
3636 if (multibyte)
3637 {
3638 c = TRANSLATE (c);
3639 len = CHAR_STRING (c, b);
3640 b += len;
3641 }
3642 else
3643 {
3644 c1 = RE_CHAR_TO_MULTIBYTE (c);
3645 if (! CHAR_BYTE8_P (c1))
3646 {
3647 re_wchar_t c2 = TRANSLATE (c1);
3648
3649 if (c1 != c2 && (c1 = RE_CHAR_TO_UNIBYTE (c2)) >= 0)
3650 c = c1;
3651 }
3652 *b++ = c;
3653 len = 1;
3654 }
3655 (*pending_exact) += len;
3656 }
3657
3658 break;
3659 } /* switch (c) */
3660 } /* while p != pend */
3661
3662
3663 /* Through the pattern now. */
3664
3665 FIXUP_ALT_JUMP ();
3666
3667 if (!COMPILE_STACK_EMPTY)
3668 FREE_STACK_RETURN (REG_EPAREN);
3669
3670 /* If we don't want backtracking, force success
3671 the first time we reach the end of the compiled pattern. */
3672 if (syntax & RE_NO_POSIX_BACKTRACKING)
3673 BUF_PUSH (succeed);
3674
3675 /* We have succeeded; set the length of the buffer. */
3676 bufp->used = b - bufp->buffer;
3677
3678 #ifdef DEBUG
3679 if (debug > 0)
3680 {
3681 re_compile_fastmap (bufp);
3682 DEBUG_PRINT ("\nCompiled pattern: \n");
3683 print_compiled_pattern (bufp);
3684 }
3685 debug--;
3686 #endif /* DEBUG */
3687
3688 #ifndef MATCH_MAY_ALLOCATE
3689 /* Initialize the failure stack to the largest possible stack. This
3690 isn't necessary unless we're trying to avoid calling alloca in
3691 the search and match routines. */
3692 {
3693 int num_regs = bufp->re_nsub + 1;
3694
3695 if (fail_stack.size < re_max_failures * TYPICAL_FAILURE_SIZE)
3696 {
3697 fail_stack.size = re_max_failures * TYPICAL_FAILURE_SIZE;
3698 falk_stack.stack = realloc (fail_stack.stack,
3699 fail_stack.size * sizeof *falk_stack.stack);
3700 }
3701
3702 regex_grow_registers (num_regs);
3703 }
3704 #endif /* not MATCH_MAY_ALLOCATE */
3705
3706 FREE_STACK_RETURN (REG_NOERROR);
3707 } /* regex_compile */
3708 \f
3709 /* Subroutines for `regex_compile'. */
3710
3711 /* Store OP at LOC followed by two-byte integer parameter ARG. */
3712
3713 static void
3714 store_op1 (re_opcode_t op, unsigned char *loc, int arg)
3715 {
3716 *loc = (unsigned char) op;
3717 STORE_NUMBER (loc + 1, arg);
3718 }
3719
3720
3721 /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
3722
3723 static void
3724 store_op2 (re_opcode_t op, unsigned char *loc, int arg1, int arg2)
3725 {
3726 *loc = (unsigned char) op;
3727 STORE_NUMBER (loc + 1, arg1);
3728 STORE_NUMBER (loc + 3, arg2);
3729 }
3730
3731
3732 /* Copy the bytes from LOC to END to open up three bytes of space at LOC
3733 for OP followed by two-byte integer parameter ARG. */
3734
3735 static void
3736 insert_op1 (re_opcode_t op, unsigned char *loc, int arg, unsigned char *end)
3737 {
3738 register unsigned char *pfrom = end;
3739 register unsigned char *pto = end + 3;
3740
3741 while (pfrom != loc)
3742 *--pto = *--pfrom;
3743
3744 store_op1 (op, loc, arg);
3745 }
3746
3747
3748 /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
3749
3750 static void
3751 insert_op2 (re_opcode_t op, unsigned char *loc, int arg1, int arg2, unsigned char *end)
3752 {
3753 register unsigned char *pfrom = end;
3754 register unsigned char *pto = end + 5;
3755
3756 while (pfrom != loc)
3757 *--pto = *--pfrom;
3758
3759 store_op2 (op, loc, arg1, arg2);
3760 }
3761
3762
3763 /* P points to just after a ^ in PATTERN. Return true if that ^ comes
3764 after an alternative or a begin-subexpression. We assume there is at
3765 least one character before the ^. */
3766
3767 static boolean
3768 at_begline_loc_p (const_re_char *pattern, const_re_char *p, reg_syntax_t syntax)
3769 {
3770 re_char *prev = p - 2;
3771 boolean odd_backslashes;
3772
3773 /* After a subexpression? */
3774 if (*prev == '(')
3775 odd_backslashes = (syntax & RE_NO_BK_PARENS) == 0;
3776
3777 /* After an alternative? */
3778 else if (*prev == '|')
3779 odd_backslashes = (syntax & RE_NO_BK_VBAR) == 0;
3780
3781 /* After a shy subexpression? */
3782 else if (*prev == ':' && (syntax & RE_SHY_GROUPS))
3783 {
3784 /* Skip over optional regnum. */
3785 while (prev - 1 >= pattern && prev[-1] >= '0' && prev[-1] <= '9')
3786 --prev;
3787
3788 if (!(prev - 2 >= pattern
3789 && prev[-1] == '?' && prev[-2] == '('))
3790 return false;
3791 prev -= 2;
3792 odd_backslashes = (syntax & RE_NO_BK_PARENS) == 0;
3793 }
3794 else
3795 return false;
3796
3797 /* Count the number of preceding backslashes. */
3798 p = prev;
3799 while (prev - 1 >= pattern && prev[-1] == '\\')
3800 --prev;
3801 return (p - prev) & odd_backslashes;
3802 }
3803
3804
3805 /* The dual of at_begline_loc_p. This one is for $. We assume there is
3806 at least one character after the $, i.e., `P < PEND'. */
3807
3808 static boolean
3809 at_endline_loc_p (const_re_char *p, const_re_char *pend, reg_syntax_t syntax)
3810 {
3811 re_char *next = p;
3812 boolean next_backslash = *next == '\\';
3813 re_char *next_next = p + 1 < pend ? p + 1 : 0;
3814
3815 return
3816 /* Before a subexpression? */
3817 (syntax & RE_NO_BK_PARENS ? *next == ')'
3818 : next_backslash && next_next && *next_next == ')')
3819 /* Before an alternative? */
3820 || (syntax & RE_NO_BK_VBAR ? *next == '|'
3821 : next_backslash && next_next && *next_next == '|');
3822 }
3823
3824
3825 /* Returns true if REGNUM is in one of COMPILE_STACK's elements and
3826 false if it's not. */
3827
3828 static boolean
3829 group_in_compile_stack (compile_stack_type compile_stack, regnum_t regnum)
3830 {
3831 ssize_t this_element;
3832
3833 for (this_element = compile_stack.avail - 1;
3834 this_element >= 0;
3835 this_element--)
3836 if (compile_stack.stack[this_element].regnum == regnum)
3837 return true;
3838
3839 return false;
3840 }
3841 \f
3842 /* analyse_first.
3843 If fastmap is non-NULL, go through the pattern and fill fastmap
3844 with all the possible leading chars. If fastmap is NULL, don't
3845 bother filling it up (obviously) and only return whether the
3846 pattern could potentially match the empty string.
3847
3848 Return 1 if p..pend might match the empty string.
3849 Return 0 if p..pend matches at least one char.
3850 Return -1 if fastmap was not updated accurately. */
3851
3852 static int
3853 analyse_first (const_re_char *p, const_re_char *pend, char *fastmap,
3854 const int multibyte)
3855 {
3856 int j, k;
3857 boolean not;
3858
3859 /* If all elements for base leading-codes in fastmap is set, this
3860 flag is set true. */
3861 boolean match_any_multibyte_characters = false;
3862
3863 assert (p);
3864
3865 /* The loop below works as follows:
3866 - It has a working-list kept in the PATTERN_STACK and which basically
3867 starts by only containing a pointer to the first operation.
3868 - If the opcode we're looking at is a match against some set of
3869 chars, then we add those chars to the fastmap and go on to the
3870 next work element from the worklist (done via `break').
3871 - If the opcode is a control operator on the other hand, we either
3872 ignore it (if it's meaningless at this point, such as `start_memory')
3873 or execute it (if it's a jump). If the jump has several destinations
3874 (i.e. `on_failure_jump'), then we push the other destination onto the
3875 worklist.
3876 We guarantee termination by ignoring backward jumps (more or less),
3877 so that `p' is monotonically increasing. More to the point, we
3878 never set `p' (or push) anything `<= p1'. */
3879
3880 while (p < pend)
3881 {
3882 /* `p1' is used as a marker of how far back a `on_failure_jump'
3883 can go without being ignored. It is normally equal to `p'
3884 (which prevents any backward `on_failure_jump') except right
3885 after a plain `jump', to allow patterns such as:
3886 0: jump 10
3887 3..9: <body>
3888 10: on_failure_jump 3
3889 as used for the *? operator. */
3890 re_char *p1 = p;
3891
3892 switch (*p++)
3893 {
3894 case succeed:
3895 return 1;
3896
3897 case duplicate:
3898 /* If the first character has to match a backreference, that means
3899 that the group was empty (since it already matched). Since this
3900 is the only case that interests us here, we can assume that the
3901 backreference must match the empty string. */
3902 p++;
3903 continue;
3904
3905
3906 /* Following are the cases which match a character. These end
3907 with `break'. */
3908
3909 case exactn:
3910 if (fastmap)
3911 {
3912 /* If multibyte is nonzero, the first byte of each
3913 character is an ASCII or a leading code. Otherwise,
3914 each byte is a character. Thus, this works in both
3915 cases. */
3916 fastmap[p[1]] = 1;
3917 if (! multibyte)
3918 {
3919 /* For the case of matching this unibyte regex
3920 against multibyte, we must set a leading code of
3921 the corresponding multibyte character. */
3922 int c = RE_CHAR_TO_MULTIBYTE (p[1]);
3923
3924 fastmap[CHAR_LEADING_CODE (c)] = 1;
3925 }
3926 }
3927 break;
3928
3929
3930 case anychar:
3931 /* We could put all the chars except for \n (and maybe \0)
3932 but we don't bother since it is generally not worth it. */
3933 if (!fastmap) break;
3934 return -1;
3935
3936
3937 case charset_not:
3938 if (!fastmap) break;
3939 {
3940 /* Chars beyond end of bitmap are possible matches. */
3941 for (j = CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH;
3942 j < (1 << BYTEWIDTH); j++)
3943 fastmap[j] = 1;
3944 }
3945
3946 /* Fallthrough */
3947 case charset:
3948 if (!fastmap) break;
3949 not = (re_opcode_t) *(p - 1) == charset_not;
3950 for (j = CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH - 1, p++;
3951 j >= 0; j--)
3952 if (!!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))) ^ not)
3953 fastmap[j] = 1;
3954
3955 #ifdef emacs
3956 if (/* Any leading code can possibly start a character
3957 which doesn't match the specified set of characters. */
3958 not
3959 ||
3960 /* If we can match a character class, we can match any
3961 multibyte characters. */
3962 (CHARSET_RANGE_TABLE_EXISTS_P (&p[-2])
3963 && CHARSET_RANGE_TABLE_BITS (&p[-2]) != 0))
3964
3965 {
3966 if (match_any_multibyte_characters == false)
3967 {
3968 for (j = MIN_MULTIBYTE_LEADING_CODE;
3969 j <= MAX_MULTIBYTE_LEADING_CODE; j++)
3970 fastmap[j] = 1;
3971 match_any_multibyte_characters = true;
3972 }
3973 }
3974
3975 else if (!not && CHARSET_RANGE_TABLE_EXISTS_P (&p[-2])
3976 && match_any_multibyte_characters == false)
3977 {
3978 /* Set fastmap[I] to 1 where I is a leading code of each
3979 multibyte character in the range table. */
3980 int c, count;
3981 unsigned char lc1, lc2;
3982
3983 /* Make P points the range table. `+ 2' is to skip flag
3984 bits for a character class. */
3985 p += CHARSET_BITMAP_SIZE (&p[-2]) + 2;
3986
3987 /* Extract the number of ranges in range table into COUNT. */
3988 EXTRACT_NUMBER_AND_INCR (count, p);
3989 for (; count > 0; count--, p += 3)
3990 {
3991 /* Extract the start and end of each range. */
3992 EXTRACT_CHARACTER (c, p);
3993 lc1 = CHAR_LEADING_CODE (c);
3994 p += 3;
3995 EXTRACT_CHARACTER (c, p);
3996 lc2 = CHAR_LEADING_CODE (c);
3997 for (j = lc1; j <= lc2; j++)
3998 fastmap[j] = 1;
3999 }
4000 }
4001 #endif
4002 break;
4003
4004 case syntaxspec:
4005 case notsyntaxspec:
4006 if (!fastmap) break;
4007 #ifndef emacs
4008 not = (re_opcode_t)p[-1] == notsyntaxspec;
4009 k = *p++;
4010 for (j = 0; j < (1 << BYTEWIDTH); j++)
4011 if ((SYNTAX (j) == (enum syntaxcode) k) ^ not)
4012 fastmap[j] = 1;
4013 break;
4014 #else /* emacs */
4015 /* This match depends on text properties. These end with
4016 aborting optimizations. */
4017 return -1;
4018
4019 case categoryspec:
4020 case notcategoryspec:
4021 if (!fastmap) break;
4022 not = (re_opcode_t)p[-1] == notcategoryspec;
4023 k = *p++;
4024 for (j = (1 << BYTEWIDTH); j >= 0; j--)
4025 if ((CHAR_HAS_CATEGORY (j, k)) ^ not)
4026 fastmap[j] = 1;
4027
4028 /* Any leading code can possibly start a character which
4029 has or doesn't has the specified category. */
4030 if (match_any_multibyte_characters == false)
4031 {
4032 for (j = MIN_MULTIBYTE_LEADING_CODE;
4033 j <= MAX_MULTIBYTE_LEADING_CODE; j++)
4034 fastmap[j] = 1;
4035 match_any_multibyte_characters = true;
4036 }
4037 break;
4038
4039 /* All cases after this match the empty string. These end with
4040 `continue'. */
4041
4042 case before_dot:
4043 case at_dot:
4044 case after_dot:
4045 #endif /* !emacs */
4046 case no_op:
4047 case begline:
4048 case endline:
4049 case begbuf:
4050 case endbuf:
4051 case wordbound:
4052 case notwordbound:
4053 case wordbeg:
4054 case wordend:
4055 case symbeg:
4056 case symend:
4057 continue;
4058
4059
4060 case jump:
4061 EXTRACT_NUMBER_AND_INCR (j, p);
4062 if (j < 0)
4063 /* Backward jumps can only go back to code that we've already
4064 visited. `re_compile' should make sure this is true. */
4065 break;
4066 p += j;
4067 switch (*p)
4068 {
4069 case on_failure_jump:
4070 case on_failure_keep_string_jump:
4071 case on_failure_jump_loop:
4072 case on_failure_jump_nastyloop:
4073 case on_failure_jump_smart:
4074 p++;
4075 break;
4076 default:
4077 continue;
4078 };
4079 /* Keep `p1' to allow the `on_failure_jump' we are jumping to
4080 to jump back to "just after here". */
4081 /* Fallthrough */
4082
4083 case on_failure_jump:
4084 case on_failure_keep_string_jump:
4085 case on_failure_jump_nastyloop:
4086 case on_failure_jump_loop:
4087 case on_failure_jump_smart:
4088 EXTRACT_NUMBER_AND_INCR (j, p);
4089 if (p + j <= p1)
4090 ; /* Backward jump to be ignored. */
4091 else
4092 { /* We have to look down both arms.
4093 We first go down the "straight" path so as to minimize
4094 stack usage when going through alternatives. */
4095 int r = analyse_first (p, pend, fastmap, multibyte);
4096 if (r) return r;
4097 p += j;
4098 }
4099 continue;
4100
4101
4102 case jump_n:
4103 /* This code simply does not properly handle forward jump_n. */
4104 DEBUG_STATEMENT (EXTRACT_NUMBER (j, p); assert (j < 0));
4105 p += 4;
4106 /* jump_n can either jump or fall through. The (backward) jump
4107 case has already been handled, so we only need to look at the
4108 fallthrough case. */
4109 continue;
4110
4111 case succeed_n:
4112 /* If N == 0, it should be an on_failure_jump_loop instead. */
4113 DEBUG_STATEMENT (EXTRACT_NUMBER (j, p + 2); assert (j > 0));
4114 p += 4;
4115 /* We only care about one iteration of the loop, so we don't
4116 need to consider the case where this behaves like an
4117 on_failure_jump. */
4118 continue;
4119
4120
4121 case set_number_at:
4122 p += 4;
4123 continue;
4124
4125
4126 case start_memory:
4127 case stop_memory:
4128 p += 1;
4129 continue;
4130
4131
4132 default:
4133 abort (); /* We have listed all the cases. */
4134 } /* switch *p++ */
4135
4136 /* Getting here means we have found the possible starting
4137 characters for one path of the pattern -- and that the empty
4138 string does not match. We need not follow this path further. */
4139 return 0;
4140 } /* while p */
4141
4142 /* We reached the end without matching anything. */
4143 return 1;
4144
4145 } /* analyse_first */
4146 \f
4147 /* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
4148 BUFP. A fastmap records which of the (1 << BYTEWIDTH) possible
4149 characters can start a string that matches the pattern. This fastmap
4150 is used by re_search to skip quickly over impossible starting points.
4151
4152 Character codes above (1 << BYTEWIDTH) are not represented in the
4153 fastmap, but the leading codes are represented. Thus, the fastmap
4154 indicates which character sets could start a match.
4155
4156 The caller must supply the address of a (1 << BYTEWIDTH)-byte data
4157 area as BUFP->fastmap.
4158
4159 We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
4160 the pattern buffer.
4161
4162 Returns 0 if we succeed, -2 if an internal error. */
4163
4164 int
4165 re_compile_fastmap (struct re_pattern_buffer *bufp)
4166 {
4167 char *fastmap = bufp->fastmap;
4168 int analysis;
4169
4170 assert (fastmap && bufp->buffer);
4171
4172 memset (fastmap, 0, 1 << BYTEWIDTH); /* Assume nothing's valid. */
4173 bufp->fastmap_accurate = 1; /* It will be when we're done. */
4174
4175 analysis = analyse_first (bufp->buffer, bufp->buffer + bufp->used,
4176 fastmap, RE_MULTIBYTE_P (bufp));
4177 bufp->can_be_null = (analysis != 0);
4178 return 0;
4179 } /* re_compile_fastmap */
4180 \f
4181 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
4182 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
4183 this memory for recording register information. STARTS and ENDS
4184 must be allocated using the malloc library routine, and must each
4185 be at least NUM_REGS * sizeof (regoff_t) bytes long.
4186
4187 If NUM_REGS == 0, then subsequent matches should allocate their own
4188 register data.
4189
4190 Unless this function is called, the first search or match using
4191 PATTERN_BUFFER will allocate its own register data, without
4192 freeing the old data. */
4193
4194 void
4195 re_set_registers (struct re_pattern_buffer *bufp, struct re_registers *regs, unsigned int num_regs, regoff_t *starts, regoff_t *ends)
4196 {
4197 if (num_regs)
4198 {
4199 bufp->regs_allocated = REGS_REALLOCATE;
4200 regs->num_regs = num_regs;
4201 regs->start = starts;
4202 regs->end = ends;
4203 }
4204 else
4205 {
4206 bufp->regs_allocated = REGS_UNALLOCATED;
4207 regs->num_regs = 0;
4208 regs->start = regs->end = 0;
4209 }
4210 }
4211 WEAK_ALIAS (__re_set_registers, re_set_registers)
4212 \f
4213 /* Searching routines. */
4214
4215 /* Like re_search_2, below, but only one string is specified, and
4216 doesn't let you say where to stop matching. */
4217
4218 regoff_t
4219 re_search (struct re_pattern_buffer *bufp, const char *string, size_t size,
4220 ssize_t startpos, ssize_t range, struct re_registers *regs)
4221 {
4222 return re_search_2 (bufp, NULL, 0, string, size, startpos, range,
4223 regs, size);
4224 }
4225 WEAK_ALIAS (__re_search, re_search)
4226
4227 /* Head address of virtual concatenation of string. */
4228 #define HEAD_ADDR_VSTRING(P) \
4229 (((P) >= size1 ? string2 : string1))
4230
4231 /* Address of POS in the concatenation of virtual string. */
4232 #define POS_ADDR_VSTRING(POS) \
4233 (((POS) >= size1 ? string2 - size1 : string1) + (POS))
4234
4235 /* Using the compiled pattern in BUFP->buffer, first tries to match the
4236 virtual concatenation of STRING1 and STRING2, starting first at index
4237 STARTPOS, then at STARTPOS + 1, and so on.
4238
4239 STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
4240
4241 RANGE is how far to scan while trying to match. RANGE = 0 means try
4242 only at STARTPOS; in general, the last start tried is STARTPOS +
4243 RANGE.
4244
4245 In REGS, return the indices of the virtual concatenation of STRING1
4246 and STRING2 that matched the entire BUFP->buffer and its contained
4247 subexpressions.
4248
4249 Do not consider matching one past the index STOP in the virtual
4250 concatenation of STRING1 and STRING2.
4251
4252 We return either the position in the strings at which the match was
4253 found, -1 if no match, or -2 if error (such as failure
4254 stack overflow). */
4255
4256 regoff_t
4257 re_search_2 (struct re_pattern_buffer *bufp, const char *str1, size_t size1,
4258 const char *str2, size_t size2, ssize_t startpos, ssize_t range,
4259 struct re_registers *regs, ssize_t stop)
4260 {
4261 regoff_t val;
4262 re_char *string1 = (re_char*) str1;
4263 re_char *string2 = (re_char*) str2;
4264 register char *fastmap = bufp->fastmap;
4265 register RE_TRANSLATE_TYPE translate = bufp->translate;
4266 size_t total_size = size1 + size2;
4267 ssize_t endpos = startpos + range;
4268 boolean anchored_start;
4269 /* Nonzero if we are searching multibyte string. */
4270 const boolean multibyte = RE_TARGET_MULTIBYTE_P (bufp);
4271
4272 /* Check for out-of-range STARTPOS. */
4273 if (startpos < 0 || startpos > total_size)
4274 return -1;
4275
4276 /* Fix up RANGE if it might eventually take us outside
4277 the virtual concatenation of STRING1 and STRING2.
4278 Make sure we won't move STARTPOS below 0 or above TOTAL_SIZE. */
4279 if (endpos < 0)
4280 range = 0 - startpos;
4281 else if (endpos > total_size)
4282 range = total_size - startpos;
4283
4284 /* If the search isn't to be a backwards one, don't waste time in a
4285 search for a pattern anchored at beginning of buffer. */
4286 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == begbuf && range > 0)
4287 {
4288 if (startpos > 0)
4289 return -1;
4290 else
4291 range = 0;
4292 }
4293
4294 #ifdef emacs
4295 /* In a forward search for something that starts with \=.
4296 don't keep searching past point. */
4297 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == at_dot && range > 0)
4298 {
4299 range = PT_BYTE - BEGV_BYTE - startpos;
4300 if (range < 0)
4301 return -1;
4302 }
4303 #endif /* emacs */
4304
4305 /* Update the fastmap now if not correct already. */
4306 if (fastmap && !bufp->fastmap_accurate)
4307 re_compile_fastmap (bufp);
4308
4309 /* See whether the pattern is anchored. */
4310 anchored_start = (bufp->buffer[0] == begline);
4311
4312 #ifdef emacs
4313 gl_state.object = re_match_object; /* Used by SYNTAX_TABLE_BYTE_TO_CHAR. */
4314 {
4315 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (POS_AS_IN_BUFFER (startpos));
4316
4317 SETUP_SYNTAX_TABLE_FOR_OBJECT (re_match_object, charpos, 1);
4318 }
4319 #endif
4320
4321 /* Loop through the string, looking for a place to start matching. */
4322 for (;;)
4323 {
4324 /* If the pattern is anchored,
4325 skip quickly past places we cannot match.
4326 We don't bother to treat startpos == 0 specially
4327 because that case doesn't repeat. */
4328 if (anchored_start && startpos > 0)
4329 {
4330 if (! ((startpos <= size1 ? string1[startpos - 1]
4331 : string2[startpos - size1 - 1])
4332 == '\n'))
4333 goto advance;
4334 }
4335
4336 /* If a fastmap is supplied, skip quickly over characters that
4337 cannot be the start of a match. If the pattern can match the
4338 null string, however, we don't need to skip characters; we want
4339 the first null string. */
4340 if (fastmap && startpos < total_size && !bufp->can_be_null)
4341 {
4342 register re_char *d;
4343 register re_wchar_t buf_ch;
4344
4345 d = POS_ADDR_VSTRING (startpos);
4346
4347 if (range > 0) /* Searching forwards. */
4348 {
4349 register int lim = 0;
4350 ssize_t irange = range;
4351
4352 if (startpos < size1 && startpos + range >= size1)
4353 lim = range - (size1 - startpos);
4354
4355 /* Written out as an if-else to avoid testing `translate'
4356 inside the loop. */
4357 if (RE_TRANSLATE_P (translate))
4358 {
4359 if (multibyte)
4360 while (range > lim)
4361 {
4362 int buf_charlen;
4363
4364 buf_ch = STRING_CHAR_AND_LENGTH (d, buf_charlen);
4365 buf_ch = RE_TRANSLATE (translate, buf_ch);
4366 if (fastmap[CHAR_LEADING_CODE (buf_ch)])
4367 break;
4368
4369 range -= buf_charlen;
4370 d += buf_charlen;
4371 }
4372 else
4373 while (range > lim)
4374 {
4375 register re_wchar_t ch, translated;
4376
4377 buf_ch = *d;
4378 ch = RE_CHAR_TO_MULTIBYTE (buf_ch);
4379 translated = RE_TRANSLATE (translate, ch);
4380 if (translated != ch
4381 && (ch = RE_CHAR_TO_UNIBYTE (translated)) >= 0)
4382 buf_ch = ch;
4383 if (fastmap[buf_ch])
4384 break;
4385 d++;
4386 range--;
4387 }
4388 }
4389 else
4390 {
4391 if (multibyte)
4392 while (range > lim)
4393 {
4394 int buf_charlen;
4395
4396 buf_ch = STRING_CHAR_AND_LENGTH (d, buf_charlen);
4397 if (fastmap[CHAR_LEADING_CODE (buf_ch)])
4398 break;
4399 range -= buf_charlen;
4400 d += buf_charlen;
4401 }
4402 else
4403 while (range > lim && !fastmap[*d])
4404 {
4405 d++;
4406 range--;
4407 }
4408 }
4409 startpos += irange - range;
4410 }
4411 else /* Searching backwards. */
4412 {
4413 if (multibyte)
4414 {
4415 buf_ch = STRING_CHAR (d);
4416 buf_ch = TRANSLATE (buf_ch);
4417 if (! fastmap[CHAR_LEADING_CODE (buf_ch)])
4418 goto advance;
4419 }
4420 else
4421 {
4422 register re_wchar_t ch, translated;
4423
4424 buf_ch = *d;
4425 ch = RE_CHAR_TO_MULTIBYTE (buf_ch);
4426 translated = TRANSLATE (ch);
4427 if (translated != ch
4428 && (ch = RE_CHAR_TO_UNIBYTE (translated)) >= 0)
4429 buf_ch = ch;
4430 if (! fastmap[TRANSLATE (buf_ch)])
4431 goto advance;
4432 }
4433 }
4434 }
4435
4436 /* If can't match the null string, and that's all we have left, fail. */
4437 if (range >= 0 && startpos == total_size && fastmap
4438 && !bufp->can_be_null)
4439 return -1;
4440
4441 val = re_match_2_internal (bufp, string1, size1, string2, size2,
4442 startpos, regs, stop);
4443
4444 if (val >= 0)
4445 return startpos;
4446
4447 if (val == -2)
4448 return -2;
4449
4450 advance:
4451 if (!range)
4452 break;
4453 else if (range > 0)
4454 {
4455 /* Update STARTPOS to the next character boundary. */
4456 if (multibyte)
4457 {
4458 re_char *p = POS_ADDR_VSTRING (startpos);
4459 int len = BYTES_BY_CHAR_HEAD (*p);
4460
4461 range -= len;
4462 if (range < 0)
4463 break;
4464 startpos += len;
4465 }
4466 else
4467 {
4468 range--;
4469 startpos++;
4470 }
4471 }
4472 else
4473 {
4474 range++;
4475 startpos--;
4476
4477 /* Update STARTPOS to the previous character boundary. */
4478 if (multibyte)
4479 {
4480 re_char *p = POS_ADDR_VSTRING (startpos) + 1;
4481 re_char *p0 = p;
4482 re_char *phead = HEAD_ADDR_VSTRING (startpos);
4483
4484 /* Find the head of multibyte form. */
4485 PREV_CHAR_BOUNDARY (p, phead);
4486 range += p0 - 1 - p;
4487 if (range > 0)
4488 break;
4489
4490 startpos -= p0 - 1 - p;
4491 }
4492 }
4493 }
4494 return -1;
4495 } /* re_search_2 */
4496 WEAK_ALIAS (__re_search_2, re_search_2)
4497 \f
4498 /* Declarations and macros for re_match_2. */
4499
4500 static int bcmp_translate (re_char *s1, re_char *s2,
4501 register ssize_t len,
4502 RE_TRANSLATE_TYPE translate,
4503 const int multibyte);
4504
4505 /* This converts PTR, a pointer into one of the search strings `string1'
4506 and `string2' into an offset from the beginning of that string. */
4507 #define POINTER_TO_OFFSET(ptr) \
4508 (FIRST_STRING_P (ptr) \
4509 ? (ptr) - string1 \
4510 : (ptr) - string2 + (ptrdiff_t) size1)
4511
4512 /* Call before fetching a character with *d. This switches over to
4513 string2 if necessary.
4514 Check re_match_2_internal for a discussion of why end_match_2 might
4515 not be within string2 (but be equal to end_match_1 instead). */
4516 #define PREFETCH() \
4517 while (d == dend) \
4518 { \
4519 /* End of string2 => fail. */ \
4520 if (dend == end_match_2) \
4521 goto fail; \
4522 /* End of string1 => advance to string2. */ \
4523 d = string2; \
4524 dend = end_match_2; \
4525 }
4526
4527 /* Call before fetching a char with *d if you already checked other limits.
4528 This is meant for use in lookahead operations like wordend, etc..
4529 where we might need to look at parts of the string that might be
4530 outside of the LIMITs (i.e past `stop'). */
4531 #define PREFETCH_NOLIMIT() \
4532 if (d == end1) \
4533 { \
4534 d = string2; \
4535 dend = end_match_2; \
4536 } \
4537
4538 /* Test if at very beginning or at very end of the virtual concatenation
4539 of `string1' and `string2'. If only one string, it's `string2'. */
4540 #define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
4541 #define AT_STRINGS_END(d) ((d) == end2)
4542
4543 /* Disabled due to a compiler bug -- see comment at case wordbound */
4544
4545 /* The comment at case wordbound is following one, but we don't use
4546 AT_WORD_BOUNDARY anymore to support multibyte form.
4547
4548 The DEC Alpha C compiler 3.x generates incorrect code for the
4549 test WORDCHAR_P (d - 1) != WORDCHAR_P (d) in the expansion of
4550 AT_WORD_BOUNDARY, so this code is disabled. Expanding the
4551 macro and introducing temporary variables works around the bug. */
4552
4553 #if 0
4554 /* Test if D points to a character which is word-constituent. We have
4555 two special cases to check for: if past the end of string1, look at
4556 the first character in string2; and if before the beginning of
4557 string2, look at the last character in string1. */
4558 #define WORDCHAR_P(d) \
4559 (SYNTAX ((d) == end1 ? *string2 \
4560 : (d) == string2 - 1 ? *(end1 - 1) : *(d)) \
4561 == Sword)
4562
4563 /* Test if the character before D and the one at D differ with respect
4564 to being word-constituent. */
4565 #define AT_WORD_BOUNDARY(d) \
4566 (AT_STRINGS_BEG (d) || AT_STRINGS_END (d) \
4567 || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
4568 #endif
4569
4570 /* Free everything we malloc. */
4571 #ifdef MATCH_MAY_ALLOCATE
4572 # define FREE_VAR(var) \
4573 do { \
4574 if (var) \
4575 { \
4576 REGEX_FREE (var); \
4577 var = NULL; \
4578 } \
4579 } while (0)
4580 # define FREE_VARIABLES() \
4581 do { \
4582 REGEX_FREE_STACK (fail_stack.stack); \
4583 FREE_VAR (regstart); \
4584 FREE_VAR (regend); \
4585 FREE_VAR (best_regstart); \
4586 FREE_VAR (best_regend); \
4587 } while (0)
4588 #else
4589 # define FREE_VARIABLES() ((void)0) /* Do nothing! But inhibit gcc warning. */
4590 #endif /* not MATCH_MAY_ALLOCATE */
4591
4592 \f
4593 /* Optimization routines. */
4594
4595 /* If the operation is a match against one or more chars,
4596 return a pointer to the next operation, else return NULL. */
4597 static re_char *
4598 skip_one_char (const_re_char *p)
4599 {
4600 switch (*p++)
4601 {
4602 case anychar:
4603 break;
4604
4605 case exactn:
4606 p += *p + 1;
4607 break;
4608
4609 case charset_not:
4610 case charset:
4611 if (CHARSET_RANGE_TABLE_EXISTS_P (p - 1))
4612 {
4613 int mcnt;
4614 p = CHARSET_RANGE_TABLE (p - 1);
4615 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4616 p = CHARSET_RANGE_TABLE_END (p, mcnt);
4617 }
4618 else
4619 p += 1 + CHARSET_BITMAP_SIZE (p - 1);
4620 break;
4621
4622 case syntaxspec:
4623 case notsyntaxspec:
4624 #ifdef emacs
4625 case categoryspec:
4626 case notcategoryspec:
4627 #endif /* emacs */
4628 p++;
4629 break;
4630
4631 default:
4632 p = NULL;
4633 }
4634 return p;
4635 }
4636
4637
4638 /* Jump over non-matching operations. */
4639 static re_char *
4640 skip_noops (const_re_char *p, const_re_char *pend)
4641 {
4642 int mcnt;
4643 while (p < pend)
4644 {
4645 switch (*p)
4646 {
4647 case start_memory:
4648 case stop_memory:
4649 p += 2; break;
4650 case no_op:
4651 p += 1; break;
4652 case jump:
4653 p += 1;
4654 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4655 p += mcnt;
4656 break;
4657 default:
4658 return p;
4659 }
4660 }
4661 assert (p == pend);
4662 return p;
4663 }
4664
4665 /* Non-zero if "p1 matches something" implies "p2 fails". */
4666 static int
4667 mutually_exclusive_p (struct re_pattern_buffer *bufp, const_re_char *p1,
4668 const_re_char *p2)
4669 {
4670 re_opcode_t op2;
4671 const boolean multibyte = RE_MULTIBYTE_P (bufp);
4672 unsigned char *pend = bufp->buffer + bufp->used;
4673
4674 assert (p1 >= bufp->buffer && p1 < pend
4675 && p2 >= bufp->buffer && p2 <= pend);
4676
4677 /* Skip over open/close-group commands.
4678 If what follows this loop is a ...+ construct,
4679 look at what begins its body, since we will have to
4680 match at least one of that. */
4681 p2 = skip_noops (p2, pend);
4682 /* The same skip can be done for p1, except that this function
4683 is only used in the case where p1 is a simple match operator. */
4684 /* p1 = skip_noops (p1, pend); */
4685
4686 assert (p1 >= bufp->buffer && p1 < pend
4687 && p2 >= bufp->buffer && p2 <= pend);
4688
4689 op2 = p2 == pend ? succeed : *p2;
4690
4691 switch (op2)
4692 {
4693 case succeed:
4694 case endbuf:
4695 /* If we're at the end of the pattern, we can change. */
4696 if (skip_one_char (p1))
4697 {
4698 DEBUG_PRINT (" End of pattern: fast loop.\n");
4699 return 1;
4700 }
4701 break;
4702
4703 case endline:
4704 case exactn:
4705 {
4706 register re_wchar_t c
4707 = (re_opcode_t) *p2 == endline ? '\n'
4708 : RE_STRING_CHAR (p2 + 2, multibyte);
4709
4710 if ((re_opcode_t) *p1 == exactn)
4711 {
4712 if (c != RE_STRING_CHAR (p1 + 2, multibyte))
4713 {
4714 DEBUG_PRINT (" '%c' != '%c' => fast loop.\n", c, p1[2]);
4715 return 1;
4716 }
4717 }
4718
4719 else if ((re_opcode_t) *p1 == charset
4720 || (re_opcode_t) *p1 == charset_not)
4721 {
4722 int not = (re_opcode_t) *p1 == charset_not;
4723
4724 /* Test if C is listed in charset (or charset_not)
4725 at `p1'. */
4726 if (! multibyte || IS_REAL_ASCII (c))
4727 {
4728 if (c < CHARSET_BITMAP_SIZE (p1) * BYTEWIDTH
4729 && p1[2 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4730 not = !not;
4731 }
4732 else if (CHARSET_RANGE_TABLE_EXISTS_P (p1))
4733 CHARSET_LOOKUP_RANGE_TABLE (not, c, p1);
4734
4735 /* `not' is equal to 1 if c would match, which means
4736 that we can't change to pop_failure_jump. */
4737 if (!not)
4738 {
4739 DEBUG_PRINT (" No match => fast loop.\n");
4740 return 1;
4741 }
4742 }
4743 else if ((re_opcode_t) *p1 == anychar
4744 && c == '\n')
4745 {
4746 DEBUG_PRINT (" . != \\n => fast loop.\n");
4747 return 1;
4748 }
4749 }
4750 break;
4751
4752 case charset:
4753 {
4754 if ((re_opcode_t) *p1 == exactn)
4755 /* Reuse the code above. */
4756 return mutually_exclusive_p (bufp, p2, p1);
4757
4758 /* It is hard to list up all the character in charset
4759 P2 if it includes multibyte character. Give up in
4760 such case. */
4761 else if (!multibyte || !CHARSET_RANGE_TABLE_EXISTS_P (p2))
4762 {
4763 /* Now, we are sure that P2 has no range table.
4764 So, for the size of bitmap in P2, `p2[1]' is
4765 enough. But P1 may have range table, so the
4766 size of bitmap table of P1 is extracted by
4767 using macro `CHARSET_BITMAP_SIZE'.
4768
4769 In a multibyte case, we know that all the character
4770 listed in P2 is ASCII. In a unibyte case, P1 has only a
4771 bitmap table. So, in both cases, it is enough to test
4772 only the bitmap table of P1. */
4773
4774 if ((re_opcode_t) *p1 == charset)
4775 {
4776 int idx;
4777 /* We win if the charset inside the loop
4778 has no overlap with the one after the loop. */
4779 for (idx = 0;
4780 (idx < (int) p2[1]
4781 && idx < CHARSET_BITMAP_SIZE (p1));
4782 idx++)
4783 if ((p2[2 + idx] & p1[2 + idx]) != 0)
4784 break;
4785
4786 if (idx == p2[1]
4787 || idx == CHARSET_BITMAP_SIZE (p1))
4788 {
4789 DEBUG_PRINT (" No match => fast loop.\n");
4790 return 1;
4791 }
4792 }
4793 else if ((re_opcode_t) *p1 == charset_not)
4794 {
4795 int idx;
4796 /* We win if the charset_not inside the loop lists
4797 every character listed in the charset after. */
4798 for (idx = 0; idx < (int) p2[1]; idx++)
4799 if (! (p2[2 + idx] == 0
4800 || (idx < CHARSET_BITMAP_SIZE (p1)
4801 && ((p2[2 + idx] & ~ p1[2 + idx]) == 0))))
4802 break;
4803
4804 if (idx == p2[1])
4805 {
4806 DEBUG_PRINT (" No match => fast loop.\n");
4807 return 1;
4808 }
4809 }
4810 }
4811 }
4812 break;
4813
4814 case charset_not:
4815 switch (*p1)
4816 {
4817 case exactn:
4818 case charset:
4819 /* Reuse the code above. */
4820 return mutually_exclusive_p (bufp, p2, p1);
4821 case charset_not:
4822 /* When we have two charset_not, it's very unlikely that
4823 they don't overlap. The union of the two sets of excluded
4824 chars should cover all possible chars, which, as a matter of
4825 fact, is virtually impossible in multibyte buffers. */
4826 break;
4827 }
4828 break;
4829
4830 case wordend:
4831 return ((re_opcode_t) *p1 == syntaxspec && p1[1] == Sword);
4832 case symend:
4833 return ((re_opcode_t) *p1 == syntaxspec
4834 && (p1[1] == Ssymbol || p1[1] == Sword));
4835 case notsyntaxspec:
4836 return ((re_opcode_t) *p1 == syntaxspec && p1[1] == p2[1]);
4837
4838 case wordbeg:
4839 return ((re_opcode_t) *p1 == notsyntaxspec && p1[1] == Sword);
4840 case symbeg:
4841 return ((re_opcode_t) *p1 == notsyntaxspec
4842 && (p1[1] == Ssymbol || p1[1] == Sword));
4843 case syntaxspec:
4844 return ((re_opcode_t) *p1 == notsyntaxspec && p1[1] == p2[1]);
4845
4846 case wordbound:
4847 return (((re_opcode_t) *p1 == notsyntaxspec
4848 || (re_opcode_t) *p1 == syntaxspec)
4849 && p1[1] == Sword);
4850
4851 #ifdef emacs
4852 case categoryspec:
4853 return ((re_opcode_t) *p1 == notcategoryspec && p1[1] == p2[1]);
4854 case notcategoryspec:
4855 return ((re_opcode_t) *p1 == categoryspec && p1[1] == p2[1]);
4856 #endif /* emacs */
4857
4858 default:
4859 ;
4860 }
4861
4862 /* Safe default. */
4863 return 0;
4864 }
4865
4866 \f
4867 /* Matching routines. */
4868
4869 #ifndef emacs /* Emacs never uses this. */
4870 /* re_match is like re_match_2 except it takes only a single string. */
4871
4872 regoff_t
4873 re_match (struct re_pattern_buffer *bufp, const char *string,
4874 size_t size, ssize_t pos, struct re_registers *regs)
4875 {
4876 regoff_t result = re_match_2_internal (bufp, NULL, 0, (re_char*) string,
4877 size, pos, regs, size);
4878 return result;
4879 }
4880 WEAK_ALIAS (__re_match, re_match)
4881 #endif /* not emacs */
4882
4883 #ifdef emacs
4884 /* In Emacs, this is the string or buffer in which we
4885 are matching. It is used for looking up syntax properties. */
4886 Lisp_Object re_match_object;
4887 #endif
4888
4889 /* re_match_2 matches the compiled pattern in BUFP against the
4890 the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
4891 and SIZE2, respectively). We start matching at POS, and stop
4892 matching at STOP.
4893
4894 If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
4895 store offsets for the substring each group matched in REGS. See the
4896 documentation for exactly how many groups we fill.
4897
4898 We return -1 if no match, -2 if an internal error (such as the
4899 failure stack overflowing). Otherwise, we return the length of the
4900 matched substring. */
4901
4902 regoff_t
4903 re_match_2 (struct re_pattern_buffer *bufp, const char *string1,
4904 size_t size1, const char *string2, size_t size2, ssize_t pos,
4905 struct re_registers *regs, ssize_t stop)
4906 {
4907 regoff_t result;
4908
4909 #ifdef emacs
4910 ssize_t charpos;
4911 gl_state.object = re_match_object; /* Used by SYNTAX_TABLE_BYTE_TO_CHAR. */
4912 charpos = SYNTAX_TABLE_BYTE_TO_CHAR (POS_AS_IN_BUFFER (pos));
4913 SETUP_SYNTAX_TABLE_FOR_OBJECT (re_match_object, charpos, 1);
4914 #endif
4915
4916 result = re_match_2_internal (bufp, (re_char*) string1, size1,
4917 (re_char*) string2, size2,
4918 pos, regs, stop);
4919 return result;
4920 }
4921 WEAK_ALIAS (__re_match_2, re_match_2)
4922
4923
4924 /* This is a separate function so that we can force an alloca cleanup
4925 afterwards. */
4926 static regoff_t
4927 re_match_2_internal (struct re_pattern_buffer *bufp, const_re_char *string1,
4928 size_t size1, const_re_char *string2, size_t size2,
4929 ssize_t pos, struct re_registers *regs, ssize_t stop)
4930 {
4931 /* General temporaries. */
4932 int mcnt;
4933 size_t reg;
4934
4935 /* Just past the end of the corresponding string. */
4936 re_char *end1, *end2;
4937
4938 /* Pointers into string1 and string2, just past the last characters in
4939 each to consider matching. */
4940 re_char *end_match_1, *end_match_2;
4941
4942 /* Where we are in the data, and the end of the current string. */
4943 re_char *d, *dend;
4944
4945 /* Used sometimes to remember where we were before starting matching
4946 an operator so that we can go back in case of failure. This "atomic"
4947 behavior of matching opcodes is indispensable to the correctness
4948 of the on_failure_keep_string_jump optimization. */
4949 re_char *dfail;
4950
4951 /* Where we are in the pattern, and the end of the pattern. */
4952 re_char *p = bufp->buffer;
4953 re_char *pend = p + bufp->used;
4954
4955 /* We use this to map every character in the string. */
4956 RE_TRANSLATE_TYPE translate = bufp->translate;
4957
4958 /* Nonzero if BUFP is setup from a multibyte regex. */
4959 const boolean multibyte = RE_MULTIBYTE_P (bufp);
4960
4961 /* Nonzero if STRING1/STRING2 are multibyte. */
4962 const boolean target_multibyte = RE_TARGET_MULTIBYTE_P (bufp);
4963
4964 /* Failure point stack. Each place that can handle a failure further
4965 down the line pushes a failure point on this stack. It consists of
4966 regstart, and regend for all registers corresponding to
4967 the subexpressions we're currently inside, plus the number of such
4968 registers, and, finally, two char *'s. The first char * is where
4969 to resume scanning the pattern; the second one is where to resume
4970 scanning the strings. */
4971 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
4972 fail_stack_type fail_stack;
4973 #endif
4974 #ifdef DEBUG_COMPILES_ARGUMENTS
4975 unsigned nfailure_points_pushed = 0, nfailure_points_popped = 0;
4976 #endif
4977
4978 #if defined REL_ALLOC && defined REGEX_MALLOC
4979 /* This holds the pointer to the failure stack, when
4980 it is allocated relocatably. */
4981 fail_stack_elt_t *failure_stack_ptr;
4982 #endif
4983
4984 /* We fill all the registers internally, independent of what we
4985 return, for use in backreferences. The number here includes
4986 an element for register zero. */
4987 size_t num_regs = bufp->re_nsub + 1;
4988
4989 /* Information on the contents of registers. These are pointers into
4990 the input strings; they record just what was matched (on this
4991 attempt) by a subexpression part of the pattern, that is, the
4992 regnum-th regstart pointer points to where in the pattern we began
4993 matching and the regnum-th regend points to right after where we
4994 stopped matching the regnum-th subexpression. (The zeroth register
4995 keeps track of what the whole pattern matches.) */
4996 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
4997 re_char **regstart, **regend;
4998 #endif
4999
5000 /* The following record the register info as found in the above
5001 variables when we find a match better than any we've seen before.
5002 This happens as we backtrack through the failure points, which in
5003 turn happens only if we have not yet matched the entire string. */
5004 unsigned best_regs_set = false;
5005 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
5006 re_char **best_regstart, **best_regend;
5007 #endif
5008
5009 /* Logically, this is `best_regend[0]'. But we don't want to have to
5010 allocate space for that if we're not allocating space for anything
5011 else (see below). Also, we never need info about register 0 for
5012 any of the other register vectors, and it seems rather a kludge to
5013 treat `best_regend' differently than the rest. So we keep track of
5014 the end of the best match so far in a separate variable. We
5015 initialize this to NULL so that when we backtrack the first time
5016 and need to test it, it's not garbage. */
5017 re_char *match_end = NULL;
5018
5019 #ifdef DEBUG_COMPILES_ARGUMENTS
5020 /* Counts the total number of registers pushed. */
5021 unsigned num_regs_pushed = 0;
5022 #endif
5023
5024 DEBUG_PRINT ("\n\nEntering re_match_2.\n");
5025
5026 INIT_FAIL_STACK ();
5027
5028 #ifdef MATCH_MAY_ALLOCATE
5029 /* Do not bother to initialize all the register variables if there are
5030 no groups in the pattern, as it takes a fair amount of time. If
5031 there are groups, we include space for register 0 (the whole
5032 pattern), even though we never use it, since it simplifies the
5033 array indexing. We should fix this. */
5034 if (bufp->re_nsub)
5035 {
5036 regstart = REGEX_TALLOC (num_regs, re_char *);
5037 regend = REGEX_TALLOC (num_regs, re_char *);
5038 best_regstart = REGEX_TALLOC (num_regs, re_char *);
5039 best_regend = REGEX_TALLOC (num_regs, re_char *);
5040
5041 if (!(regstart && regend && best_regstart && best_regend))
5042 {
5043 FREE_VARIABLES ();
5044 return -2;
5045 }
5046 }
5047 else
5048 {
5049 /* We must initialize all our variables to NULL, so that
5050 `FREE_VARIABLES' doesn't try to free them. */
5051 regstart = regend = best_regstart = best_regend = NULL;
5052 }
5053 #endif /* MATCH_MAY_ALLOCATE */
5054
5055 /* The starting position is bogus. */
5056 if (pos < 0 || pos > size1 + size2)
5057 {
5058 FREE_VARIABLES ();
5059 return -1;
5060 }
5061
5062 /* Initialize subexpression text positions to -1 to mark ones that no
5063 start_memory/stop_memory has been seen for. Also initialize the
5064 register information struct. */
5065 for (reg = 1; reg < num_regs; reg++)
5066 regstart[reg] = regend[reg] = NULL;
5067
5068 /* We move `string1' into `string2' if the latter's empty -- but not if
5069 `string1' is null. */
5070 if (size2 == 0 && string1 != NULL)
5071 {
5072 string2 = string1;
5073 size2 = size1;
5074 string1 = 0;
5075 size1 = 0;
5076 }
5077 end1 = string1 + size1;
5078 end2 = string2 + size2;
5079
5080 /* `p' scans through the pattern as `d' scans through the data.
5081 `dend' is the end of the input string that `d' points within. `d'
5082 is advanced into the following input string whenever necessary, but
5083 this happens before fetching; therefore, at the beginning of the
5084 loop, `d' can be pointing at the end of a string, but it cannot
5085 equal `string2'. */
5086 if (pos >= size1)
5087 {
5088 /* Only match within string2. */
5089 d = string2 + pos - size1;
5090 dend = end_match_2 = string2 + stop - size1;
5091 end_match_1 = end1; /* Just to give it a value. */
5092 }
5093 else
5094 {
5095 if (stop < size1)
5096 {
5097 /* Only match within string1. */
5098 end_match_1 = string1 + stop;
5099 /* BEWARE!
5100 When we reach end_match_1, PREFETCH normally switches to string2.
5101 But in the present case, this means that just doing a PREFETCH
5102 makes us jump from `stop' to `gap' within the string.
5103 What we really want here is for the search to stop as
5104 soon as we hit end_match_1. That's why we set end_match_2
5105 to end_match_1 (since PREFETCH fails as soon as we hit
5106 end_match_2). */
5107 end_match_2 = end_match_1;
5108 }
5109 else
5110 { /* It's important to use this code when stop == size so that
5111 moving `d' from end1 to string2 will not prevent the d == dend
5112 check from catching the end of string. */
5113 end_match_1 = end1;
5114 end_match_2 = string2 + stop - size1;
5115 }
5116 d = string1 + pos;
5117 dend = end_match_1;
5118 }
5119
5120 DEBUG_PRINT ("The compiled pattern is: ");
5121 DEBUG_PRINT_COMPILED_PATTERN (bufp, p, pend);
5122 DEBUG_PRINT ("The string to match is: `");
5123 DEBUG_PRINT_DOUBLE_STRING (d, string1, size1, string2, size2);
5124 DEBUG_PRINT ("'\n");
5125
5126 /* This loops over pattern commands. It exits by returning from the
5127 function if the match is complete, or it drops through if the match
5128 fails at this starting point in the input data. */
5129 for (;;)
5130 {
5131 DEBUG_PRINT ("\n%p: ", p);
5132
5133 if (p == pend)
5134 {
5135 ptrdiff_t dcnt;
5136
5137 /* End of pattern means we might have succeeded. */
5138 DEBUG_PRINT ("end of pattern ... ");
5139
5140 /* If we haven't matched the entire string, and we want the
5141 longest match, try backtracking. */
5142 if (d != end_match_2)
5143 {
5144 /* 1 if this match ends in the same string (string1 or string2)
5145 as the best previous match. */
5146 boolean same_str_p = (FIRST_STRING_P (match_end)
5147 == FIRST_STRING_P (d));
5148 /* 1 if this match is the best seen so far. */
5149 boolean best_match_p;
5150
5151 /* AIX compiler got confused when this was combined
5152 with the previous declaration. */
5153 if (same_str_p)
5154 best_match_p = d > match_end;
5155 else
5156 best_match_p = !FIRST_STRING_P (d);
5157
5158 DEBUG_PRINT ("backtracking.\n");
5159
5160 if (!FAIL_STACK_EMPTY ())
5161 { /* More failure points to try. */
5162
5163 /* If exceeds best match so far, save it. */
5164 if (!best_regs_set || best_match_p)
5165 {
5166 best_regs_set = true;
5167 match_end = d;
5168
5169 DEBUG_PRINT ("\nSAVING match as best so far.\n");
5170
5171 for (reg = 1; reg < num_regs; reg++)
5172 {
5173 best_regstart[reg] = regstart[reg];
5174 best_regend[reg] = regend[reg];
5175 }
5176 }
5177 goto fail;
5178 }
5179
5180 /* If no failure points, don't restore garbage. And if
5181 last match is real best match, don't restore second
5182 best one. */
5183 else if (best_regs_set && !best_match_p)
5184 {
5185 restore_best_regs:
5186 /* Restore best match. It may happen that `dend ==
5187 end_match_1' while the restored d is in string2.
5188 For example, the pattern `x.*y.*z' against the
5189 strings `x-' and `y-z-', if the two strings are
5190 not consecutive in memory. */
5191 DEBUG_PRINT ("Restoring best registers.\n");
5192
5193 d = match_end;
5194 dend = ((d >= string1 && d <= end1)
5195 ? end_match_1 : end_match_2);
5196
5197 for (reg = 1; reg < num_regs; reg++)
5198 {
5199 regstart[reg] = best_regstart[reg];
5200 regend[reg] = best_regend[reg];
5201 }
5202 }
5203 } /* d != end_match_2 */
5204
5205 succeed_label:
5206 DEBUG_PRINT ("Accepting match.\n");
5207
5208 /* If caller wants register contents data back, do it. */
5209 if (regs && !bufp->no_sub)
5210 {
5211 /* Have the register data arrays been allocated? */
5212 if (bufp->regs_allocated == REGS_UNALLOCATED)
5213 { /* No. So allocate them with malloc. We need one
5214 extra element beyond `num_regs' for the `-1' marker
5215 GNU code uses. */
5216 regs->num_regs = MAX (RE_NREGS, num_regs + 1);
5217 regs->start = TALLOC (regs->num_regs, regoff_t);
5218 regs->end = TALLOC (regs->num_regs, regoff_t);
5219 if (regs->start == NULL || regs->end == NULL)
5220 {
5221 FREE_VARIABLES ();
5222 return -2;
5223 }
5224 bufp->regs_allocated = REGS_REALLOCATE;
5225 }
5226 else if (bufp->regs_allocated == REGS_REALLOCATE)
5227 { /* Yes. If we need more elements than were already
5228 allocated, reallocate them. If we need fewer, just
5229 leave it alone. */
5230 if (regs->num_regs < num_regs + 1)
5231 {
5232 regs->num_regs = num_regs + 1;
5233 RETALLOC (regs->start, regs->num_regs, regoff_t);
5234 RETALLOC (regs->end, regs->num_regs, regoff_t);
5235 if (regs->start == NULL || regs->end == NULL)
5236 {
5237 FREE_VARIABLES ();
5238 return -2;
5239 }
5240 }
5241 }
5242 else
5243 {
5244 /* These braces fend off a "empty body in an else-statement"
5245 warning under GCC when assert expands to nothing. */
5246 assert (bufp->regs_allocated == REGS_FIXED);
5247 }
5248
5249 /* Convert the pointer data in `regstart' and `regend' to
5250 indices. Register zero has to be set differently,
5251 since we haven't kept track of any info for it. */
5252 if (regs->num_regs > 0)
5253 {
5254 regs->start[0] = pos;
5255 regs->end[0] = POINTER_TO_OFFSET (d);
5256 }
5257
5258 /* Go through the first `min (num_regs, regs->num_regs)'
5259 registers, since that is all we initialized. */
5260 for (reg = 1; reg < MIN (num_regs, regs->num_regs); reg++)
5261 {
5262 if (REG_UNSET (regstart[reg]) || REG_UNSET (regend[reg]))
5263 regs->start[reg] = regs->end[reg] = -1;
5264 else
5265 {
5266 regs->start[reg] = POINTER_TO_OFFSET (regstart[reg]);
5267 regs->end[reg] = POINTER_TO_OFFSET (regend[reg]);
5268 }
5269 }
5270
5271 /* If the regs structure we return has more elements than
5272 were in the pattern, set the extra elements to -1. If
5273 we (re)allocated the registers, this is the case,
5274 because we always allocate enough to have at least one
5275 -1 at the end. */
5276 for (reg = num_regs; reg < regs->num_regs; reg++)
5277 regs->start[reg] = regs->end[reg] = -1;
5278 } /* regs && !bufp->no_sub */
5279
5280 DEBUG_PRINT ("%u failure points pushed, %u popped (%u remain).\n",
5281 nfailure_points_pushed, nfailure_points_popped,
5282 nfailure_points_pushed - nfailure_points_popped);
5283 DEBUG_PRINT ("%u registers pushed.\n", num_regs_pushed);
5284
5285 dcnt = POINTER_TO_OFFSET (d) - pos;
5286
5287 DEBUG_PRINT ("Returning %td from re_match_2.\n", dcnt);
5288
5289 FREE_VARIABLES ();
5290 return dcnt;
5291 }
5292
5293 /* Otherwise match next pattern command. */
5294 switch (*p++)
5295 {
5296 /* Ignore these. Used to ignore the n of succeed_n's which
5297 currently have n == 0. */
5298 case no_op:
5299 DEBUG_PRINT ("EXECUTING no_op.\n");
5300 break;
5301
5302 case succeed:
5303 DEBUG_PRINT ("EXECUTING succeed.\n");
5304 goto succeed_label;
5305
5306 /* Match the next n pattern characters exactly. The following
5307 byte in the pattern defines n, and the n bytes after that
5308 are the characters to match. */
5309 case exactn:
5310 mcnt = *p++;
5311 DEBUG_PRINT ("EXECUTING exactn %d.\n", mcnt);
5312
5313 /* Remember the start point to rollback upon failure. */
5314 dfail = d;
5315
5316 #ifndef emacs
5317 /* This is written out as an if-else so we don't waste time
5318 testing `translate' inside the loop. */
5319 if (RE_TRANSLATE_P (translate))
5320 do
5321 {
5322 PREFETCH ();
5323 if (RE_TRANSLATE (translate, *d) != *p++)
5324 {
5325 d = dfail;
5326 goto fail;
5327 }
5328 d++;
5329 }
5330 while (--mcnt);
5331 else
5332 do
5333 {
5334 PREFETCH ();
5335 if (*d++ != *p++)
5336 {
5337 d = dfail;
5338 goto fail;
5339 }
5340 }
5341 while (--mcnt);
5342 #else /* emacs */
5343 /* The cost of testing `translate' is comparatively small. */
5344 if (target_multibyte)
5345 do
5346 {
5347 int pat_charlen, buf_charlen;
5348 int pat_ch, buf_ch;
5349
5350 PREFETCH ();
5351 if (multibyte)
5352 pat_ch = STRING_CHAR_AND_LENGTH (p, pat_charlen);
5353 else
5354 {
5355 pat_ch = RE_CHAR_TO_MULTIBYTE (*p);
5356 pat_charlen = 1;
5357 }
5358 buf_ch = STRING_CHAR_AND_LENGTH (d, buf_charlen);
5359
5360 if (TRANSLATE (buf_ch) != pat_ch)
5361 {
5362 d = dfail;
5363 goto fail;
5364 }
5365
5366 p += pat_charlen;
5367 d += buf_charlen;
5368 mcnt -= pat_charlen;
5369 }
5370 while (mcnt > 0);
5371 else
5372 do
5373 {
5374 int pat_charlen;
5375 int pat_ch, buf_ch;
5376
5377 PREFETCH ();
5378 if (multibyte)
5379 {
5380 pat_ch = STRING_CHAR_AND_LENGTH (p, pat_charlen);
5381 pat_ch = RE_CHAR_TO_UNIBYTE (pat_ch);
5382 }
5383 else
5384 {
5385 pat_ch = *p;
5386 pat_charlen = 1;
5387 }
5388 buf_ch = RE_CHAR_TO_MULTIBYTE (*d);
5389 if (! CHAR_BYTE8_P (buf_ch))
5390 {
5391 buf_ch = TRANSLATE (buf_ch);
5392 buf_ch = RE_CHAR_TO_UNIBYTE (buf_ch);
5393 if (buf_ch < 0)
5394 buf_ch = *d;
5395 }
5396 else
5397 buf_ch = *d;
5398 if (buf_ch != pat_ch)
5399 {
5400 d = dfail;
5401 goto fail;
5402 }
5403 p += pat_charlen;
5404 d++;
5405 }
5406 while (--mcnt);
5407 #endif
5408 break;
5409
5410
5411 /* Match any character except possibly a newline or a null. */
5412 case anychar:
5413 {
5414 int buf_charlen;
5415 re_wchar_t buf_ch;
5416
5417 DEBUG_PRINT ("EXECUTING anychar.\n");
5418
5419 PREFETCH ();
5420 buf_ch = RE_STRING_CHAR_AND_LENGTH (d, buf_charlen,
5421 target_multibyte);
5422 buf_ch = TRANSLATE (buf_ch);
5423
5424 if ((!(bufp->syntax & RE_DOT_NEWLINE)
5425 && buf_ch == '\n')
5426 || ((bufp->syntax & RE_DOT_NOT_NULL)
5427 && buf_ch == '\000'))
5428 goto fail;
5429
5430 DEBUG_PRINT (" Matched `%d'.\n", *d);
5431 d += buf_charlen;
5432 }
5433 break;
5434
5435
5436 case charset:
5437 case charset_not:
5438 {
5439 register unsigned int c;
5440 boolean not = (re_opcode_t) *(p - 1) == charset_not;
5441 int len;
5442
5443 /* Start of actual range_table, or end of bitmap if there is no
5444 range table. */
5445 re_char *range_table IF_LINT (= NULL);
5446
5447 /* Nonzero if there is a range table. */
5448 int range_table_exists;
5449
5450 /* Number of ranges of range table. This is not included
5451 in the initial byte-length of the command. */
5452 int count = 0;
5453
5454 /* Whether matching against a unibyte character. */
5455 boolean unibyte_char = false;
5456
5457 DEBUG_PRINT ("EXECUTING charset%s.\n", not ? "_not" : "");
5458
5459 range_table_exists = CHARSET_RANGE_TABLE_EXISTS_P (&p[-1]);
5460
5461 if (range_table_exists)
5462 {
5463 range_table = CHARSET_RANGE_TABLE (&p[-1]); /* Past the bitmap. */
5464 EXTRACT_NUMBER_AND_INCR (count, range_table);
5465 }
5466
5467 PREFETCH ();
5468 c = RE_STRING_CHAR_AND_LENGTH (d, len, target_multibyte);
5469 if (target_multibyte)
5470 {
5471 int c1;
5472
5473 c = TRANSLATE (c);
5474 c1 = RE_CHAR_TO_UNIBYTE (c);
5475 if (c1 >= 0)
5476 {
5477 unibyte_char = true;
5478 c = c1;
5479 }
5480 }
5481 else
5482 {
5483 int c1 = RE_CHAR_TO_MULTIBYTE (c);
5484
5485 if (! CHAR_BYTE8_P (c1))
5486 {
5487 c1 = TRANSLATE (c1);
5488 c1 = RE_CHAR_TO_UNIBYTE (c1);
5489 if (c1 >= 0)
5490 {
5491 unibyte_char = true;
5492 c = c1;
5493 }
5494 }
5495 else
5496 unibyte_char = true;
5497 }
5498
5499 if (unibyte_char && c < (1 << BYTEWIDTH))
5500 { /* Lookup bitmap. */
5501 /* Cast to `unsigned' instead of `unsigned char' in
5502 case the bit list is a full 32 bytes long. */
5503 if (c < (unsigned) (CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH)
5504 && p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
5505 not = !not;
5506 }
5507 #ifdef emacs
5508 else if (range_table_exists)
5509 {
5510 int class_bits = CHARSET_RANGE_TABLE_BITS (&p[-1]);
5511
5512 if ( (class_bits & BIT_LOWER && ISLOWER (c))
5513 | (class_bits & BIT_MULTIBYTE)
5514 | (class_bits & BIT_PUNCT && ISPUNCT (c))
5515 | (class_bits & BIT_SPACE && ISSPACE (c))
5516 | (class_bits & BIT_UPPER && ISUPPER (c))
5517 | (class_bits & BIT_WORD && ISWORD (c)))
5518 not = !not;
5519 else
5520 CHARSET_LOOKUP_RANGE_TABLE_RAW (not, c, range_table, count);
5521 }
5522 #endif /* emacs */
5523
5524 if (range_table_exists)
5525 p = CHARSET_RANGE_TABLE_END (range_table, count);
5526 else
5527 p += CHARSET_BITMAP_SIZE (&p[-1]) + 1;
5528
5529 if (!not) goto fail;
5530
5531 d += len;
5532 }
5533 break;
5534
5535
5536 /* The beginning of a group is represented by start_memory.
5537 The argument is the register number. The text
5538 matched within the group is recorded (in the internal
5539 registers data structure) under the register number. */
5540 case start_memory:
5541 DEBUG_PRINT ("EXECUTING start_memory %d:\n", *p);
5542
5543 /* In case we need to undo this operation (via backtracking). */
5544 PUSH_FAILURE_REG (*p);
5545
5546 regstart[*p] = d;
5547 regend[*p] = NULL; /* probably unnecessary. -sm */
5548 DEBUG_PRINT (" regstart: %td\n", POINTER_TO_OFFSET (regstart[*p]));
5549
5550 /* Move past the register number and inner group count. */
5551 p += 1;
5552 break;
5553
5554
5555 /* The stop_memory opcode represents the end of a group. Its
5556 argument is the same as start_memory's: the register number. */
5557 case stop_memory:
5558 DEBUG_PRINT ("EXECUTING stop_memory %d:\n", *p);
5559
5560 assert (!REG_UNSET (regstart[*p]));
5561 /* Strictly speaking, there should be code such as:
5562
5563 assert (REG_UNSET (regend[*p]));
5564 PUSH_FAILURE_REGSTOP ((unsigned int)*p);
5565
5566 But the only info to be pushed is regend[*p] and it is known to
5567 be UNSET, so there really isn't anything to push.
5568 Not pushing anything, on the other hand deprives us from the
5569 guarantee that regend[*p] is UNSET since undoing this operation
5570 will not reset its value properly. This is not important since
5571 the value will only be read on the next start_memory or at
5572 the very end and both events can only happen if this stop_memory
5573 is *not* undone. */
5574
5575 regend[*p] = d;
5576 DEBUG_PRINT (" regend: %td\n", POINTER_TO_OFFSET (regend[*p]));
5577
5578 /* Move past the register number and the inner group count. */
5579 p += 1;
5580 break;
5581
5582
5583 /* \<digit> has been turned into a `duplicate' command which is
5584 followed by the numeric value of <digit> as the register number. */
5585 case duplicate:
5586 {
5587 register re_char *d2, *dend2;
5588 int regno = *p++; /* Get which register to match against. */
5589 DEBUG_PRINT ("EXECUTING duplicate %d.\n", regno);
5590
5591 /* Can't back reference a group which we've never matched. */
5592 if (REG_UNSET (regstart[regno]) || REG_UNSET (regend[regno]))
5593 goto fail;
5594
5595 /* Where in input to try to start matching. */
5596 d2 = regstart[regno];
5597
5598 /* Remember the start point to rollback upon failure. */
5599 dfail = d;
5600
5601 /* Where to stop matching; if both the place to start and
5602 the place to stop matching are in the same string, then
5603 set to the place to stop, otherwise, for now have to use
5604 the end of the first string. */
5605
5606 dend2 = ((FIRST_STRING_P (regstart[regno])
5607 == FIRST_STRING_P (regend[regno]))
5608 ? regend[regno] : end_match_1);
5609 for (;;)
5610 {
5611 ptrdiff_t dcnt;
5612
5613 /* If necessary, advance to next segment in register
5614 contents. */
5615 while (d2 == dend2)
5616 {
5617 if (dend2 == end_match_2) break;
5618 if (dend2 == regend[regno]) break;
5619
5620 /* End of string1 => advance to string2. */
5621 d2 = string2;
5622 dend2 = regend[regno];
5623 }
5624 /* At end of register contents => success */
5625 if (d2 == dend2) break;
5626
5627 /* If necessary, advance to next segment in data. */
5628 PREFETCH ();
5629
5630 /* How many characters left in this segment to match. */
5631 dcnt = dend - d;
5632
5633 /* Want how many consecutive characters we can match in
5634 one shot, so, if necessary, adjust the count. */
5635 if (dcnt > dend2 - d2)
5636 dcnt = dend2 - d2;
5637
5638 /* Compare that many; failure if mismatch, else move
5639 past them. */
5640 if (RE_TRANSLATE_P (translate)
5641 ? bcmp_translate (d, d2, dcnt, translate, target_multibyte)
5642 : memcmp (d, d2, dcnt))
5643 {
5644 d = dfail;
5645 goto fail;
5646 }
5647 d += dcnt, d2 += dcnt;
5648 }
5649 }
5650 break;
5651
5652
5653 /* begline matches the empty string at the beginning of the string
5654 (unless `not_bol' is set in `bufp'), and after newlines. */
5655 case begline:
5656 DEBUG_PRINT ("EXECUTING begline.\n");
5657
5658 if (AT_STRINGS_BEG (d))
5659 {
5660 if (!bufp->not_bol) break;
5661 }
5662 else
5663 {
5664 unsigned c;
5665 GET_CHAR_BEFORE_2 (c, d, string1, end1, string2, end2);
5666 if (c == '\n')
5667 break;
5668 }
5669 /* In all other cases, we fail. */
5670 goto fail;
5671
5672
5673 /* endline is the dual of begline. */
5674 case endline:
5675 DEBUG_PRINT ("EXECUTING endline.\n");
5676
5677 if (AT_STRINGS_END (d))
5678 {
5679 if (!bufp->not_eol) break;
5680 }
5681 else
5682 {
5683 PREFETCH_NOLIMIT ();
5684 if (*d == '\n')
5685 break;
5686 }
5687 goto fail;
5688
5689
5690 /* Match at the very beginning of the data. */
5691 case begbuf:
5692 DEBUG_PRINT ("EXECUTING begbuf.\n");
5693 if (AT_STRINGS_BEG (d))
5694 break;
5695 goto fail;
5696
5697
5698 /* Match at the very end of the data. */
5699 case endbuf:
5700 DEBUG_PRINT ("EXECUTING endbuf.\n");
5701 if (AT_STRINGS_END (d))
5702 break;
5703 goto fail;
5704
5705
5706 /* on_failure_keep_string_jump is used to optimize `.*\n'. It
5707 pushes NULL as the value for the string on the stack. Then
5708 `POP_FAILURE_POINT' will keep the current value for the
5709 string, instead of restoring it. To see why, consider
5710 matching `foo\nbar' against `.*\n'. The .* matches the foo;
5711 then the . fails against the \n. But the next thing we want
5712 to do is match the \n against the \n; if we restored the
5713 string value, we would be back at the foo.
5714
5715 Because this is used only in specific cases, we don't need to
5716 check all the things that `on_failure_jump' does, to make
5717 sure the right things get saved on the stack. Hence we don't
5718 share its code. The only reason to push anything on the
5719 stack at all is that otherwise we would have to change
5720 `anychar's code to do something besides goto fail in this
5721 case; that seems worse than this. */
5722 case on_failure_keep_string_jump:
5723 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5724 DEBUG_PRINT ("EXECUTING on_failure_keep_string_jump %d (to %p):\n",
5725 mcnt, p + mcnt);
5726
5727 PUSH_FAILURE_POINT (p - 3, NULL);
5728 break;
5729
5730 /* A nasty loop is introduced by the non-greedy *? and +?.
5731 With such loops, the stack only ever contains one failure point
5732 at a time, so that a plain on_failure_jump_loop kind of
5733 cycle detection cannot work. Worse yet, such a detection
5734 can not only fail to detect a cycle, but it can also wrongly
5735 detect a cycle (between different instantiations of the same
5736 loop).
5737 So the method used for those nasty loops is a little different:
5738 We use a special cycle-detection-stack-frame which is pushed
5739 when the on_failure_jump_nastyloop failure-point is *popped*.
5740 This special frame thus marks the beginning of one iteration
5741 through the loop and we can hence easily check right here
5742 whether something matched between the beginning and the end of
5743 the loop. */
5744 case on_failure_jump_nastyloop:
5745 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5746 DEBUG_PRINT ("EXECUTING on_failure_jump_nastyloop %d (to %p):\n",
5747 mcnt, p + mcnt);
5748
5749 assert ((re_opcode_t)p[-4] == no_op);
5750 {
5751 int cycle = 0;
5752 CHECK_INFINITE_LOOP (p - 4, d);
5753 if (!cycle)
5754 /* If there's a cycle, just continue without pushing
5755 this failure point. The failure point is the "try again"
5756 option, which shouldn't be tried.
5757 We want (x?)*?y\1z to match both xxyz and xxyxz. */
5758 PUSH_FAILURE_POINT (p - 3, d);
5759 }
5760 break;
5761
5762 /* Simple loop detecting on_failure_jump: just check on the
5763 failure stack if the same spot was already hit earlier. */
5764 case on_failure_jump_loop:
5765 on_failure:
5766 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5767 DEBUG_PRINT ("EXECUTING on_failure_jump_loop %d (to %p):\n",
5768 mcnt, p + mcnt);
5769 {
5770 int cycle = 0;
5771 CHECK_INFINITE_LOOP (p - 3, d);
5772 if (cycle)
5773 /* If there's a cycle, get out of the loop, as if the matching
5774 had failed. We used to just `goto fail' here, but that was
5775 aborting the search a bit too early: we want to keep the
5776 empty-loop-match and keep matching after the loop.
5777 We want (x?)*y\1z to match both xxyz and xxyxz. */
5778 p += mcnt;
5779 else
5780 PUSH_FAILURE_POINT (p - 3, d);
5781 }
5782 break;
5783
5784
5785 /* Uses of on_failure_jump:
5786
5787 Each alternative starts with an on_failure_jump that points
5788 to the beginning of the next alternative. Each alternative
5789 except the last ends with a jump that in effect jumps past
5790 the rest of the alternatives. (They really jump to the
5791 ending jump of the following alternative, because tensioning
5792 these jumps is a hassle.)
5793
5794 Repeats start with an on_failure_jump that points past both
5795 the repetition text and either the following jump or
5796 pop_failure_jump back to this on_failure_jump. */
5797 case on_failure_jump:
5798 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5799 DEBUG_PRINT ("EXECUTING on_failure_jump %d (to %p):\n",
5800 mcnt, p + mcnt);
5801
5802 PUSH_FAILURE_POINT (p -3, d);
5803 break;
5804
5805 /* This operation is used for greedy *.
5806 Compare the beginning of the repeat with what in the
5807 pattern follows its end. If we can establish that there
5808 is nothing that they would both match, i.e., that we
5809 would have to backtrack because of (as in, e.g., `a*a')
5810 then we can use a non-backtracking loop based on
5811 on_failure_keep_string_jump instead of on_failure_jump. */
5812 case on_failure_jump_smart:
5813 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5814 DEBUG_PRINT ("EXECUTING on_failure_jump_smart %d (to %p).\n",
5815 mcnt, p + mcnt);
5816 {
5817 re_char *p1 = p; /* Next operation. */
5818 /* Here, we discard `const', making re_match non-reentrant. */
5819 unsigned char *p2 = (unsigned char*) p + mcnt; /* Jump dest. */
5820 unsigned char *p3 = (unsigned char*) p - 3; /* opcode location. */
5821
5822 p -= 3; /* Reset so that we will re-execute the
5823 instruction once it's been changed. */
5824
5825 EXTRACT_NUMBER (mcnt, p2 - 2);
5826
5827 /* Ensure this is a indeed the trivial kind of loop
5828 we are expecting. */
5829 assert (skip_one_char (p1) == p2 - 3);
5830 assert ((re_opcode_t) p2[-3] == jump && p2 + mcnt == p);
5831 DEBUG_STATEMENT (debug += 2);
5832 if (mutually_exclusive_p (bufp, p1, p2))
5833 {
5834 /* Use a fast `on_failure_keep_string_jump' loop. */
5835 DEBUG_PRINT (" smart exclusive => fast loop.\n");
5836 *p3 = (unsigned char) on_failure_keep_string_jump;
5837 STORE_NUMBER (p2 - 2, mcnt + 3);
5838 }
5839 else
5840 {
5841 /* Default to a safe `on_failure_jump' loop. */
5842 DEBUG_PRINT (" smart default => slow loop.\n");
5843 *p3 = (unsigned char) on_failure_jump;
5844 }
5845 DEBUG_STATEMENT (debug -= 2);
5846 }
5847 break;
5848
5849 /* Unconditionally jump (without popping any failure points). */
5850 case jump:
5851 unconditional_jump:
5852 IMMEDIATE_QUIT_CHECK;
5853 EXTRACT_NUMBER_AND_INCR (mcnt, p); /* Get the amount to jump. */
5854 DEBUG_PRINT ("EXECUTING jump %d ", mcnt);
5855 p += mcnt; /* Do the jump. */
5856 DEBUG_PRINT ("(to %p).\n", p);
5857 break;
5858
5859
5860 /* Have to succeed matching what follows at least n times.
5861 After that, handle like `on_failure_jump'. */
5862 case succeed_n:
5863 /* Signedness doesn't matter since we only compare MCNT to 0. */
5864 EXTRACT_NUMBER (mcnt, p + 2);
5865 DEBUG_PRINT ("EXECUTING succeed_n %d.\n", mcnt);
5866
5867 /* Originally, mcnt is how many times we HAVE to succeed. */
5868 if (mcnt != 0)
5869 {
5870 /* Here, we discard `const', making re_match non-reentrant. */
5871 unsigned char *p2 = (unsigned char*) p + 2; /* counter loc. */
5872 mcnt--;
5873 p += 4;
5874 PUSH_NUMBER (p2, mcnt);
5875 }
5876 else
5877 /* The two bytes encoding mcnt == 0 are two no_op opcodes. */
5878 goto on_failure;
5879 break;
5880
5881 case jump_n:
5882 /* Signedness doesn't matter since we only compare MCNT to 0. */
5883 EXTRACT_NUMBER (mcnt, p + 2);
5884 DEBUG_PRINT ("EXECUTING jump_n %d.\n", mcnt);
5885
5886 /* Originally, this is how many times we CAN jump. */
5887 if (mcnt != 0)
5888 {
5889 /* Here, we discard `const', making re_match non-reentrant. */
5890 unsigned char *p2 = (unsigned char*) p + 2; /* counter loc. */
5891 mcnt--;
5892 PUSH_NUMBER (p2, mcnt);
5893 goto unconditional_jump;
5894 }
5895 /* If don't have to jump any more, skip over the rest of command. */
5896 else
5897 p += 4;
5898 break;
5899
5900 case set_number_at:
5901 {
5902 unsigned char *p2; /* Location of the counter. */
5903 DEBUG_PRINT ("EXECUTING set_number_at.\n");
5904
5905 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5906 /* Here, we discard `const', making re_match non-reentrant. */
5907 p2 = (unsigned char*) p + mcnt;
5908 /* Signedness doesn't matter since we only copy MCNT's bits. */
5909 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5910 DEBUG_PRINT (" Setting %p to %d.\n", p2, mcnt);
5911 PUSH_NUMBER (p2, mcnt);
5912 break;
5913 }
5914
5915 case wordbound:
5916 case notwordbound:
5917 {
5918 boolean not = (re_opcode_t) *(p - 1) == notwordbound;
5919 DEBUG_PRINT ("EXECUTING %swordbound.\n", not ? "not" : "");
5920
5921 /* We SUCCEED (or FAIL) in one of the following cases: */
5922
5923 /* Case 1: D is at the beginning or the end of string. */
5924 if (AT_STRINGS_BEG (d) || AT_STRINGS_END (d))
5925 not = !not;
5926 else
5927 {
5928 /* C1 is the character before D, S1 is the syntax of C1, C2
5929 is the character at D, and S2 is the syntax of C2. */
5930 re_wchar_t c1, c2;
5931 int s1, s2;
5932 int dummy;
5933 #ifdef emacs
5934 ssize_t offset = PTR_TO_OFFSET (d - 1);
5935 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5936 UPDATE_SYNTAX_TABLE (charpos);
5937 #endif
5938 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5939 s1 = SYNTAX (c1);
5940 #ifdef emacs
5941 UPDATE_SYNTAX_TABLE_FORWARD (charpos + 1);
5942 #endif
5943 PREFETCH_NOLIMIT ();
5944 GET_CHAR_AFTER (c2, d, dummy);
5945 s2 = SYNTAX (c2);
5946
5947 if (/* Case 2: Only one of S1 and S2 is Sword. */
5948 ((s1 == Sword) != (s2 == Sword))
5949 /* Case 3: Both of S1 and S2 are Sword, and macro
5950 WORD_BOUNDARY_P (C1, C2) returns nonzero. */
5951 || ((s1 == Sword) && WORD_BOUNDARY_P (c1, c2)))
5952 not = !not;
5953 }
5954 if (not)
5955 break;
5956 else
5957 goto fail;
5958 }
5959
5960 case wordbeg:
5961 DEBUG_PRINT ("EXECUTING wordbeg.\n");
5962
5963 /* We FAIL in one of the following cases: */
5964
5965 /* Case 1: D is at the end of string. */
5966 if (AT_STRINGS_END (d))
5967 goto fail;
5968 else
5969 {
5970 /* C1 is the character before D, S1 is the syntax of C1, C2
5971 is the character at D, and S2 is the syntax of C2. */
5972 re_wchar_t c1, c2;
5973 int s1, s2;
5974 int dummy;
5975 #ifdef emacs
5976 ssize_t offset = PTR_TO_OFFSET (d);
5977 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5978 UPDATE_SYNTAX_TABLE (charpos);
5979 #endif
5980 PREFETCH ();
5981 GET_CHAR_AFTER (c2, d, dummy);
5982 s2 = SYNTAX (c2);
5983
5984 /* Case 2: S2 is not Sword. */
5985 if (s2 != Sword)
5986 goto fail;
5987
5988 /* Case 3: D is not at the beginning of string ... */
5989 if (!AT_STRINGS_BEG (d))
5990 {
5991 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5992 #ifdef emacs
5993 UPDATE_SYNTAX_TABLE_BACKWARD (charpos - 1);
5994 #endif
5995 s1 = SYNTAX (c1);
5996
5997 /* ... and S1 is Sword, and WORD_BOUNDARY_P (C1, C2)
5998 returns 0. */
5999 if ((s1 == Sword) && !WORD_BOUNDARY_P (c1, c2))
6000 goto fail;
6001 }
6002 }
6003 break;
6004
6005 case wordend:
6006 DEBUG_PRINT ("EXECUTING wordend.\n");
6007
6008 /* We FAIL in one of the following cases: */
6009
6010 /* Case 1: D is at the beginning of string. */
6011 if (AT_STRINGS_BEG (d))
6012 goto fail;
6013 else
6014 {
6015 /* C1 is the character before D, S1 is the syntax of C1, C2
6016 is the character at D, and S2 is the syntax of C2. */
6017 re_wchar_t c1, c2;
6018 int s1, s2;
6019 int dummy;
6020 #ifdef emacs
6021 ssize_t offset = PTR_TO_OFFSET (d) - 1;
6022 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
6023 UPDATE_SYNTAX_TABLE (charpos);
6024 #endif
6025 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
6026 s1 = SYNTAX (c1);
6027
6028 /* Case 2: S1 is not Sword. */
6029 if (s1 != Sword)
6030 goto fail;
6031
6032 /* Case 3: D is not at the end of string ... */
6033 if (!AT_STRINGS_END (d))
6034 {
6035 PREFETCH_NOLIMIT ();
6036 GET_CHAR_AFTER (c2, d, dummy);
6037 #ifdef emacs
6038 UPDATE_SYNTAX_TABLE_FORWARD (charpos);
6039 #endif
6040 s2 = SYNTAX (c2);
6041
6042 /* ... and S2 is Sword, and WORD_BOUNDARY_P (C1, C2)
6043 returns 0. */
6044 if ((s2 == Sword) && !WORD_BOUNDARY_P (c1, c2))
6045 goto fail;
6046 }
6047 }
6048 break;
6049
6050 case symbeg:
6051 DEBUG_PRINT ("EXECUTING symbeg.\n");
6052
6053 /* We FAIL in one of the following cases: */
6054
6055 /* Case 1: D is at the end of string. */
6056 if (AT_STRINGS_END (d))
6057 goto fail;
6058 else
6059 {
6060 /* C1 is the character before D, S1 is the syntax of C1, C2
6061 is the character at D, and S2 is the syntax of C2. */
6062 re_wchar_t c1, c2;
6063 int s1, s2;
6064 #ifdef emacs
6065 ssize_t offset = PTR_TO_OFFSET (d);
6066 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
6067 UPDATE_SYNTAX_TABLE (charpos);
6068 #endif
6069 PREFETCH ();
6070 c2 = RE_STRING_CHAR (d, target_multibyte);
6071 s2 = SYNTAX (c2);
6072
6073 /* Case 2: S2 is neither Sword nor Ssymbol. */
6074 if (s2 != Sword && s2 != Ssymbol)
6075 goto fail;
6076
6077 /* Case 3: D is not at the beginning of string ... */
6078 if (!AT_STRINGS_BEG (d))
6079 {
6080 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
6081 #ifdef emacs
6082 UPDATE_SYNTAX_TABLE_BACKWARD (charpos - 1);
6083 #endif
6084 s1 = SYNTAX (c1);
6085
6086 /* ... and S1 is Sword or Ssymbol. */
6087 if (s1 == Sword || s1 == Ssymbol)
6088 goto fail;
6089 }
6090 }
6091 break;
6092
6093 case symend:
6094 DEBUG_PRINT ("EXECUTING symend.\n");
6095
6096 /* We FAIL in one of the following cases: */
6097
6098 /* Case 1: D is at the beginning of string. */
6099 if (AT_STRINGS_BEG (d))
6100 goto fail;
6101 else
6102 {
6103 /* C1 is the character before D, S1 is the syntax of C1, C2
6104 is the character at D, and S2 is the syntax of C2. */
6105 re_wchar_t c1, c2;
6106 int s1, s2;
6107 #ifdef emacs
6108 ssize_t offset = PTR_TO_OFFSET (d) - 1;
6109 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
6110 UPDATE_SYNTAX_TABLE (charpos);
6111 #endif
6112 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
6113 s1 = SYNTAX (c1);
6114
6115 /* Case 2: S1 is neither Ssymbol nor Sword. */
6116 if (s1 != Sword && s1 != Ssymbol)
6117 goto fail;
6118
6119 /* Case 3: D is not at the end of string ... */
6120 if (!AT_STRINGS_END (d))
6121 {
6122 PREFETCH_NOLIMIT ();
6123 c2 = RE_STRING_CHAR (d, target_multibyte);
6124 #ifdef emacs
6125 UPDATE_SYNTAX_TABLE_FORWARD (charpos + 1);
6126 #endif
6127 s2 = SYNTAX (c2);
6128
6129 /* ... and S2 is Sword or Ssymbol. */
6130 if (s2 == Sword || s2 == Ssymbol)
6131 goto fail;
6132 }
6133 }
6134 break;
6135
6136 case syntaxspec:
6137 case notsyntaxspec:
6138 {
6139 boolean not = (re_opcode_t) *(p - 1) == notsyntaxspec;
6140 mcnt = *p++;
6141 DEBUG_PRINT ("EXECUTING %ssyntaxspec %d.\n", not ? "not" : "",
6142 mcnt);
6143 PREFETCH ();
6144 #ifdef emacs
6145 {
6146 ssize_t offset = PTR_TO_OFFSET (d);
6147 ssize_t pos1 = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
6148 UPDATE_SYNTAX_TABLE (pos1);
6149 }
6150 #endif
6151 {
6152 int len;
6153 re_wchar_t c;
6154
6155 GET_CHAR_AFTER (c, d, len);
6156 if ((SYNTAX (c) != (enum syntaxcode) mcnt) ^ not)
6157 goto fail;
6158 d += len;
6159 }
6160 }
6161 break;
6162
6163 #ifdef emacs
6164 case before_dot:
6165 DEBUG_PRINT ("EXECUTING before_dot.\n");
6166 if (PTR_BYTE_POS (d) >= PT_BYTE)
6167 goto fail;
6168 break;
6169
6170 case at_dot:
6171 DEBUG_PRINT ("EXECUTING at_dot.\n");
6172 if (PTR_BYTE_POS (d) != PT_BYTE)
6173 goto fail;
6174 break;
6175
6176 case after_dot:
6177 DEBUG_PRINT ("EXECUTING after_dot.\n");
6178 if (PTR_BYTE_POS (d) <= PT_BYTE)
6179 goto fail;
6180 break;
6181
6182 case categoryspec:
6183 case notcategoryspec:
6184 {
6185 boolean not = (re_opcode_t) *(p - 1) == notcategoryspec;
6186 mcnt = *p++;
6187 DEBUG_PRINT ("EXECUTING %scategoryspec %d.\n",
6188 not ? "not" : "", mcnt);
6189 PREFETCH ();
6190
6191 {
6192 int len;
6193 re_wchar_t c;
6194 GET_CHAR_AFTER (c, d, len);
6195 if ((!CHAR_HAS_CATEGORY (c, mcnt)) ^ not)
6196 goto fail;
6197 d += len;
6198 }
6199 }
6200 break;
6201
6202 #endif /* emacs */
6203
6204 default:
6205 abort ();
6206 }
6207 continue; /* Successfully executed one pattern command; keep going. */
6208
6209
6210 /* We goto here if a matching operation fails. */
6211 fail:
6212 IMMEDIATE_QUIT_CHECK;
6213 if (!FAIL_STACK_EMPTY ())
6214 {
6215 re_char *str, *pat;
6216 /* A restart point is known. Restore to that state. */
6217 DEBUG_PRINT ("\nFAIL:\n");
6218 POP_FAILURE_POINT (str, pat);
6219 switch (*pat++)
6220 {
6221 case on_failure_keep_string_jump:
6222 assert (str == NULL);
6223 goto continue_failure_jump;
6224
6225 case on_failure_jump_nastyloop:
6226 assert ((re_opcode_t)pat[-2] == no_op);
6227 PUSH_FAILURE_POINT (pat - 2, str);
6228 /* Fallthrough */
6229
6230 case on_failure_jump_loop:
6231 case on_failure_jump:
6232 case succeed_n:
6233 d = str;
6234 continue_failure_jump:
6235 EXTRACT_NUMBER_AND_INCR (mcnt, pat);
6236 p = pat + mcnt;
6237 break;
6238
6239 case no_op:
6240 /* A special frame used for nastyloops. */
6241 goto fail;
6242
6243 default:
6244 abort ();
6245 }
6246
6247 assert (p >= bufp->buffer && p <= pend);
6248
6249 if (d >= string1 && d <= end1)
6250 dend = end_match_1;
6251 }
6252 else
6253 break; /* Matching at this starting point really fails. */
6254 } /* for (;;) */
6255
6256 if (best_regs_set)
6257 goto restore_best_regs;
6258
6259 FREE_VARIABLES ();
6260
6261 return -1; /* Failure to match. */
6262 }
6263 \f
6264 /* Subroutine definitions for re_match_2. */
6265
6266 /* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
6267 bytes; nonzero otherwise. */
6268
6269 static int
6270 bcmp_translate (const_re_char *s1, const_re_char *s2, register ssize_t len,
6271 RE_TRANSLATE_TYPE translate, const int target_multibyte)
6272 {
6273 register re_char *p1 = s1, *p2 = s2;
6274 re_char *p1_end = s1 + len;
6275 re_char *p2_end = s2 + len;
6276
6277 /* FIXME: Checking both p1 and p2 presumes that the two strings might have
6278 different lengths, but relying on a single `len' would break this. -sm */
6279 while (p1 < p1_end && p2 < p2_end)
6280 {
6281 int p1_charlen, p2_charlen;
6282 re_wchar_t p1_ch, p2_ch;
6283
6284 GET_CHAR_AFTER (p1_ch, p1, p1_charlen);
6285 GET_CHAR_AFTER (p2_ch, p2, p2_charlen);
6286
6287 if (RE_TRANSLATE (translate, p1_ch)
6288 != RE_TRANSLATE (translate, p2_ch))
6289 return 1;
6290
6291 p1 += p1_charlen, p2 += p2_charlen;
6292 }
6293
6294 if (p1 != p1_end || p2 != p2_end)
6295 return 1;
6296
6297 return 0;
6298 }
6299 \f
6300 /* Entry points for GNU code. */
6301
6302 /* re_compile_pattern is the GNU regular expression compiler: it
6303 compiles PATTERN (of length SIZE) and puts the result in BUFP.
6304 Returns 0 if the pattern was valid, otherwise an error string.
6305
6306 Assumes the `allocated' (and perhaps `buffer') and `translate' fields
6307 are set in BUFP on entry.
6308
6309 We call regex_compile to do the actual compilation. */
6310
6311 const char *
6312 re_compile_pattern (const char *pattern, size_t length,
6313 struct re_pattern_buffer *bufp)
6314 {
6315 reg_errcode_t ret;
6316
6317 /* GNU code is written to assume at least RE_NREGS registers will be set
6318 (and at least one extra will be -1). */
6319 bufp->regs_allocated = REGS_UNALLOCATED;
6320
6321 /* And GNU code determines whether or not to get register information
6322 by passing null for the REGS argument to re_match, etc., not by
6323 setting no_sub. */
6324 bufp->no_sub = 0;
6325
6326 ret = regex_compile ((re_char*) pattern, length, re_syntax_options, bufp);
6327
6328 if (!ret)
6329 return NULL;
6330 return gettext (re_error_msgid[(int) ret]);
6331 }
6332 WEAK_ALIAS (__re_compile_pattern, re_compile_pattern)
6333 \f
6334 /* Entry points compatible with 4.2 BSD regex library. We don't define
6335 them unless specifically requested. */
6336
6337 #if defined _REGEX_RE_COMP || defined _LIBC
6338
6339 /* BSD has one and only one pattern buffer. */
6340 static struct re_pattern_buffer re_comp_buf;
6341
6342 char *
6343 # ifdef _LIBC
6344 /* Make these definitions weak in libc, so POSIX programs can redefine
6345 these names if they don't use our functions, and still use
6346 regcomp/regexec below without link errors. */
6347 weak_function
6348 # endif
6349 re_comp (const char *s)
6350 {
6351 reg_errcode_t ret;
6352
6353 if (!s)
6354 {
6355 if (!re_comp_buf.buffer)
6356 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6357 return (char *) gettext ("No previous regular expression");
6358 return 0;
6359 }
6360
6361 if (!re_comp_buf.buffer)
6362 {
6363 re_comp_buf.buffer = malloc (200);
6364 if (re_comp_buf.buffer == NULL)
6365 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6366 return (char *) gettext (re_error_msgid[(int) REG_ESPACE]);
6367 re_comp_buf.allocated = 200;
6368
6369 re_comp_buf.fastmap = malloc (1 << BYTEWIDTH);
6370 if (re_comp_buf.fastmap == NULL)
6371 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6372 return (char *) gettext (re_error_msgid[(int) REG_ESPACE]);
6373 }
6374
6375 /* Since `re_exec' always passes NULL for the `regs' argument, we
6376 don't need to initialize the pattern buffer fields which affect it. */
6377
6378 ret = regex_compile (s, strlen (s), re_syntax_options, &re_comp_buf);
6379
6380 if (!ret)
6381 return NULL;
6382
6383 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6384 return (char *) gettext (re_error_msgid[(int) ret]);
6385 }
6386
6387
6388 int
6389 # ifdef _LIBC
6390 weak_function
6391 # endif
6392 re_exec (const char *s)
6393 {
6394 const size_t len = strlen (s);
6395 return re_search (&re_comp_buf, s, len, 0, len, 0) >= 0;
6396 }
6397 #endif /* _REGEX_RE_COMP */
6398 \f
6399 /* POSIX.2 functions. Don't define these for Emacs. */
6400
6401 #ifndef emacs
6402
6403 /* regcomp takes a regular expression as a string and compiles it.
6404
6405 PREG is a regex_t *. We do not expect any fields to be initialized,
6406 since POSIX says we shouldn't. Thus, we set
6407
6408 `buffer' to the compiled pattern;
6409 `used' to the length of the compiled pattern;
6410 `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
6411 REG_EXTENDED bit in CFLAGS is set; otherwise, to
6412 RE_SYNTAX_POSIX_BASIC;
6413 `fastmap' to an allocated space for the fastmap;
6414 `fastmap_accurate' to zero;
6415 `re_nsub' to the number of subexpressions in PATTERN.
6416
6417 PATTERN is the address of the pattern string.
6418
6419 CFLAGS is a series of bits which affect compilation.
6420
6421 If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
6422 use POSIX basic syntax.
6423
6424 If REG_NEWLINE is set, then . and [^...] don't match newline.
6425 Also, regexec will try a match beginning after every newline.
6426
6427 If REG_ICASE is set, then we considers upper- and lowercase
6428 versions of letters to be equivalent when matching.
6429
6430 If REG_NOSUB is set, then when PREG is passed to regexec, that
6431 routine will report only success or failure, and nothing about the
6432 registers.
6433
6434 It returns 0 if it succeeds, nonzero if it doesn't. (See regex.h for
6435 the return codes and their meanings.) */
6436
6437 reg_errcode_t
6438 regcomp (regex_t *_Restrict_ preg, const char *_Restrict_ pattern,
6439 int cflags)
6440 {
6441 reg_errcode_t ret;
6442 reg_syntax_t syntax
6443 = (cflags & REG_EXTENDED) ?
6444 RE_SYNTAX_POSIX_EXTENDED : RE_SYNTAX_POSIX_BASIC;
6445
6446 /* regex_compile will allocate the space for the compiled pattern. */
6447 preg->buffer = 0;
6448 preg->allocated = 0;
6449 preg->used = 0;
6450
6451 /* Try to allocate space for the fastmap. */
6452 preg->fastmap = malloc (1 << BYTEWIDTH);
6453
6454 if (cflags & REG_ICASE)
6455 {
6456 unsigned i;
6457
6458 preg->translate = malloc (CHAR_SET_SIZE * sizeof *preg->translate);
6459 if (preg->translate == NULL)
6460 return (int) REG_ESPACE;
6461
6462 /* Map uppercase characters to corresponding lowercase ones. */
6463 for (i = 0; i < CHAR_SET_SIZE; i++)
6464 preg->translate[i] = ISUPPER (i) ? TOLOWER (i) : i;
6465 }
6466 else
6467 preg->translate = NULL;
6468
6469 /* If REG_NEWLINE is set, newlines are treated differently. */
6470 if (cflags & REG_NEWLINE)
6471 { /* REG_NEWLINE implies neither . nor [^...] match newline. */
6472 syntax &= ~RE_DOT_NEWLINE;
6473 syntax |= RE_HAT_LISTS_NOT_NEWLINE;
6474 }
6475 else
6476 syntax |= RE_NO_NEWLINE_ANCHOR;
6477
6478 preg->no_sub = !!(cflags & REG_NOSUB);
6479
6480 /* POSIX says a null character in the pattern terminates it, so we
6481 can use strlen here in compiling the pattern. */
6482 ret = regex_compile ((re_char*) pattern, strlen (pattern), syntax, preg);
6483
6484 /* POSIX doesn't distinguish between an unmatched open-group and an
6485 unmatched close-group: both are REG_EPAREN. */
6486 if (ret == REG_ERPAREN)
6487 ret = REG_EPAREN;
6488
6489 if (ret == REG_NOERROR && preg->fastmap)
6490 { /* Compute the fastmap now, since regexec cannot modify the pattern
6491 buffer. */
6492 re_compile_fastmap (preg);
6493 if (preg->can_be_null)
6494 { /* The fastmap can't be used anyway. */
6495 free (preg->fastmap);
6496 preg->fastmap = NULL;
6497 }
6498 }
6499 return ret;
6500 }
6501 WEAK_ALIAS (__regcomp, regcomp)
6502
6503
6504 /* regexec searches for a given pattern, specified by PREG, in the
6505 string STRING.
6506
6507 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
6508 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
6509 least NMATCH elements, and we set them to the offsets of the
6510 corresponding matched substrings.
6511
6512 EFLAGS specifies `execution flags' which affect matching: if
6513 REG_NOTBOL is set, then ^ does not match at the beginning of the
6514 string; if REG_NOTEOL is set, then $ does not match at the end.
6515
6516 We return 0 if we find a match and REG_NOMATCH if not. */
6517
6518 reg_errcode_t
6519 regexec (const regex_t *_Restrict_ preg, const char *_Restrict_ string,
6520 size_t nmatch, regmatch_t pmatch[_Restrict_arr_], int eflags)
6521 {
6522 regoff_t ret;
6523 struct re_registers regs;
6524 regex_t private_preg;
6525 size_t len = strlen (string);
6526 boolean want_reg_info = !preg->no_sub && nmatch > 0 && pmatch;
6527
6528 private_preg = *preg;
6529
6530 private_preg.not_bol = !!(eflags & REG_NOTBOL);
6531 private_preg.not_eol = !!(eflags & REG_NOTEOL);
6532
6533 /* The user has told us exactly how many registers to return
6534 information about, via `nmatch'. We have to pass that on to the
6535 matching routines. */
6536 private_preg.regs_allocated = REGS_FIXED;
6537
6538 if (want_reg_info)
6539 {
6540 regs.num_regs = nmatch;
6541 regs.start = TALLOC (nmatch * 2, regoff_t);
6542 if (regs.start == NULL)
6543 return REG_NOMATCH;
6544 regs.end = regs.start + nmatch;
6545 }
6546
6547 /* Instead of using not_eol to implement REG_NOTEOL, we could simply
6548 pass (&private_preg, string, len + 1, 0, len, ...) pretending the string
6549 was a little bit longer but still only matching the real part.
6550 This works because the `endline' will check for a '\n' and will find a
6551 '\0', correctly deciding that this is not the end of a line.
6552 But it doesn't work out so nicely for REG_NOTBOL, since we don't have
6553 a convenient '\0' there. For all we know, the string could be preceded
6554 by '\n' which would throw things off. */
6555
6556 /* Perform the searching operation. */
6557 ret = re_search (&private_preg, string, len,
6558 /* start: */ 0, /* range: */ len,
6559 want_reg_info ? &regs : 0);
6560
6561 /* Copy the register information to the POSIX structure. */
6562 if (want_reg_info)
6563 {
6564 if (ret >= 0)
6565 {
6566 unsigned r;
6567
6568 for (r = 0; r < nmatch; r++)
6569 {
6570 pmatch[r].rm_so = regs.start[r];
6571 pmatch[r].rm_eo = regs.end[r];
6572 }
6573 }
6574
6575 /* If we needed the temporary register info, free the space now. */
6576 free (regs.start);
6577 }
6578
6579 /* We want zero return to mean success, unlike `re_search'. */
6580 return ret >= 0 ? REG_NOERROR : REG_NOMATCH;
6581 }
6582 WEAK_ALIAS (__regexec, regexec)
6583
6584
6585 /* Returns a message corresponding to an error code, ERR_CODE, returned
6586 from either regcomp or regexec. We don't use PREG here.
6587
6588 ERR_CODE was previously called ERRCODE, but that name causes an
6589 error with msvc8 compiler. */
6590
6591 size_t
6592 regerror (int err_code, const regex_t *preg, char *errbuf, size_t errbuf_size)
6593 {
6594 const char *msg;
6595 size_t msg_size;
6596
6597 if (err_code < 0
6598 || err_code >= (sizeof (re_error_msgid) / sizeof (re_error_msgid[0])))
6599 /* Only error codes returned by the rest of the code should be passed
6600 to this routine. If we are given anything else, or if other regex
6601 code generates an invalid error code, then the program has a bug.
6602 Dump core so we can fix it. */
6603 abort ();
6604
6605 msg = gettext (re_error_msgid[err_code]);
6606
6607 msg_size = strlen (msg) + 1; /* Includes the null. */
6608
6609 if (errbuf_size != 0)
6610 {
6611 if (msg_size > errbuf_size)
6612 {
6613 memcpy (errbuf, msg, errbuf_size - 1);
6614 errbuf[errbuf_size - 1] = 0;
6615 }
6616 else
6617 strcpy (errbuf, msg);
6618 }
6619
6620 return msg_size;
6621 }
6622 WEAK_ALIAS (__regerror, regerror)
6623
6624
6625 /* Free dynamically allocated space used by PREG. */
6626
6627 void
6628 regfree (regex_t *preg)
6629 {
6630 free (preg->buffer);
6631 preg->buffer = NULL;
6632
6633 preg->allocated = 0;
6634 preg->used = 0;
6635
6636 free (preg->fastmap);
6637 preg->fastmap = NULL;
6638 preg->fastmap_accurate = 0;
6639
6640 free (preg->translate);
6641 preg->translate = NULL;
6642 }
6643 WEAK_ALIAS (__regfree, regfree)
6644
6645 #endif /* not emacs */