Revert changes of 2003-03-03 and 2003-05-28.
[emacs.git] / src / regex.c
blobf55cc5aeb614b7249d54680b2c5529ce82ea40c9
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.)
5 Copyright (C) 1993,94,95,96,97,98,99,2000 Free Software Foundation, Inc.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
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.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
20 USA. */
22 /* TODO:
23 - structure the opcode space into opcode+flag.
24 - merge with glibc's regex.[ch].
25 - replace (succeed_n + jump_n + set_number_at) with something that doesn't
26 need to modify the compiled regexp so that re_match can be reentrant.
27 - get rid of on_failure_jump_smart by doing the optimization in re_comp
28 rather than at run-time, so that re_match can be reentrant.
31 /* AIX requires this to be the first thing in the file. */
32 #if defined _AIX && !defined REGEX_MALLOC
33 #pragma alloca
34 #endif
36 #ifdef HAVE_CONFIG_H
37 # include <config.h>
38 #endif
40 #if defined STDC_HEADERS && !defined emacs
41 # include <stddef.h>
42 #else
43 /* We need this for `regex.h', and perhaps for the Emacs include files. */
44 # include <sys/types.h>
45 #endif
47 /* Whether to use ISO C Amendment 1 wide char functions.
48 Those should not be used for Emacs since it uses its own. */
49 #if defined _LIBC
50 #define WIDE_CHAR_SUPPORT 1
51 #else
52 #define WIDE_CHAR_SUPPORT \
53 (HAVE_WCTYPE_H && HAVE_WCHAR_H && HAVE_BTOWC && !emacs)
54 #endif
56 /* For platform which support the ISO C amendement 1 functionality we
57 support user defined character classes. */
58 #if WIDE_CHAR_SUPPORT
59 /* Solaris 2.5 has a bug: <wchar.h> must be included before <wctype.h>. */
60 # include <wchar.h>
61 # include <wctype.h>
62 #endif
64 #ifdef _LIBC
65 /* We have to keep the namespace clean. */
66 # define regfree(preg) __regfree (preg)
67 # define regexec(pr, st, nm, pm, ef) __regexec (pr, st, nm, pm, ef)
68 # define regcomp(preg, pattern, cflags) __regcomp (preg, pattern, cflags)
69 # define regerror(errcode, preg, errbuf, errbuf_size) \
70 __regerror(errcode, preg, errbuf, errbuf_size)
71 # define re_set_registers(bu, re, nu, st, en) \
72 __re_set_registers (bu, re, nu, st, en)
73 # define re_match_2(bufp, string1, size1, string2, size2, pos, regs, stop) \
74 __re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
75 # define re_match(bufp, string, size, pos, regs) \
76 __re_match (bufp, string, size, pos, regs)
77 # define re_search(bufp, string, size, startpos, range, regs) \
78 __re_search (bufp, string, size, startpos, range, regs)
79 # define re_compile_pattern(pattern, length, bufp) \
80 __re_compile_pattern (pattern, length, bufp)
81 # define re_set_syntax(syntax) __re_set_syntax (syntax)
82 # define re_search_2(bufp, st1, s1, st2, s2, startpos, range, regs, stop) \
83 __re_search_2 (bufp, st1, s1, st2, s2, startpos, range, regs, stop)
84 # define re_compile_fastmap(bufp) __re_compile_fastmap (bufp)
86 /* Make sure we call libc's function even if the user overrides them. */
87 # define btowc __btowc
88 # define iswctype __iswctype
89 # define wctype __wctype
91 # define WEAK_ALIAS(a,b) weak_alias (a, b)
93 /* We are also using some library internals. */
94 # include <locale/localeinfo.h>
95 # include <locale/elem-hash.h>
96 # include <langinfo.h>
97 #else
98 # define WEAK_ALIAS(a,b)
99 #endif
101 /* This is for other GNU distributions with internationalized messages. */
102 #if HAVE_LIBINTL_H || defined _LIBC
103 # include <libintl.h>
104 #else
105 # define gettext(msgid) (msgid)
106 #endif
108 #ifndef gettext_noop
109 /* This define is so xgettext can find the internationalizable
110 strings. */
111 # define gettext_noop(String) String
112 #endif
114 /* The `emacs' switch turns on certain matching commands
115 that make sense only in Emacs. */
116 #ifdef emacs
118 # include "lisp.h"
119 # include "buffer.h"
121 /* Make syntax table lookup grant data in gl_state. */
122 # define SYNTAX_ENTRY_VIA_PROPERTY
124 # include "syntax.h"
125 # include "charset.h"
126 # include "category.h"
128 # ifdef malloc
129 # undef malloc
130 # endif
131 # define malloc xmalloc
132 # ifdef realloc
133 # undef realloc
134 # endif
135 # define realloc xrealloc
136 # ifdef free
137 # undef free
138 # endif
139 # define free xfree
141 /* Converts the pointer to the char to BEG-based offset from the start. */
142 # define PTR_TO_OFFSET(d) POS_AS_IN_BUFFER (POINTER_TO_OFFSET (d))
143 # define POS_AS_IN_BUFFER(p) ((p) + (NILP (re_match_object) || BUFFERP (re_match_object)))
145 # define RE_MULTIBYTE_P(bufp) ((bufp)->multibyte)
146 # define RE_STRING_CHAR(p, s) \
147 (multibyte ? (STRING_CHAR (p, s)) : (*(p)))
148 # define RE_STRING_CHAR_AND_LENGTH(p, s, len) \
149 (multibyte ? (STRING_CHAR_AND_LENGTH (p, s, len)) : ((len) = 1, *(p)))
151 /* Set C a (possibly multibyte) character before P. P points into a
152 string which is the virtual concatenation of STR1 (which ends at
153 END1) or STR2 (which ends at END2). */
154 # define GET_CHAR_BEFORE_2(c, p, str1, end1, str2, end2) \
155 do { \
156 if (multibyte) \
158 re_char *dtemp = (p) == (str2) ? (end1) : (p); \
159 re_char *dlimit = ((p) > (str2) && (p) <= (end2)) ? (str2) : (str1); \
160 re_char *d0 = dtemp; \
161 PREV_CHAR_BOUNDARY (d0, dlimit); \
162 c = STRING_CHAR (d0, dtemp - d0); \
164 else \
165 (c = ((p) == (str2) ? (end1) : (p))[-1]); \
166 } while (0)
169 #else /* not emacs */
171 /* If we are not linking with Emacs proper,
172 we can't use the relocating allocator
173 even if config.h says that we can. */
174 # undef REL_ALLOC
176 # if defined STDC_HEADERS || defined _LIBC
177 # include <stdlib.h>
178 # else
179 char *malloc ();
180 char *realloc ();
181 # endif
183 /* When used in Emacs's lib-src, we need to get bzero and bcopy somehow.
184 If nothing else has been done, use the method below. */
185 # ifdef INHIBIT_STRING_HEADER
186 # if !(defined HAVE_BZERO && defined HAVE_BCOPY)
187 # if !defined bzero && !defined bcopy
188 # undef INHIBIT_STRING_HEADER
189 # endif
190 # endif
191 # endif
193 /* This is the normal way of making sure we have memcpy, memcmp and bzero.
194 This is used in most programs--a few other programs avoid this
195 by defining INHIBIT_STRING_HEADER. */
196 # ifndef INHIBIT_STRING_HEADER
197 # if defined HAVE_STRING_H || defined STDC_HEADERS || defined _LIBC
198 # include <string.h>
199 # ifndef bzero
200 # ifndef _LIBC
201 # define bzero(s, n) (memset (s, '\0', n), (s))
202 # else
203 # define bzero(s, n) __bzero (s, n)
204 # endif
205 # endif
206 # else
207 # include <strings.h>
208 # ifndef memcmp
209 # define memcmp(s1, s2, n) bcmp (s1, s2, n)
210 # endif
211 # ifndef memcpy
212 # define memcpy(d, s, n) (bcopy (s, d, n), (d))
213 # endif
214 # endif
215 # endif
217 /* Define the syntax stuff for \<, \>, etc. */
219 /* Sword must be nonzero for the wordchar pattern commands in re_match_2. */
220 enum syntaxcode { Swhitespace = 0, Sword = 1 };
222 # ifdef SWITCH_ENUM_BUG
223 # define SWITCH_ENUM_CAST(x) ((int)(x))
224 # else
225 # define SWITCH_ENUM_CAST(x) (x)
226 # endif
228 /* Dummy macros for non-Emacs environments. */
229 # define BASE_LEADING_CODE_P(c) (0)
230 # define CHAR_CHARSET(c) 0
231 # define CHARSET_LEADING_CODE_BASE(c) 0
232 # define MAX_MULTIBYTE_LENGTH 1
233 # define RE_MULTIBYTE_P(x) 0
234 # define WORD_BOUNDARY_P(c1, c2) (0)
235 # define CHAR_HEAD_P(p) (1)
236 # define SINGLE_BYTE_CHAR_P(c) (1)
237 # define SAME_CHARSET_P(c1, c2) (1)
238 # define MULTIBYTE_FORM_LENGTH(p, s) (1)
239 # define PREV_CHAR_BOUNDARY(p, limit) ((p)--)
240 # define STRING_CHAR(p, s) (*(p))
241 # define RE_STRING_CHAR STRING_CHAR
242 # define CHAR_STRING(c, s) (*(s) = (c), 1)
243 # define STRING_CHAR_AND_LENGTH(p, s, actual_len) ((actual_len) = 1, *(p))
244 # define RE_STRING_CHAR_AND_LENGTH STRING_CHAR_AND_LENGTH
245 # define GET_CHAR_BEFORE_2(c, p, str1, end1, str2, end2) \
246 (c = ((p) == (str2) ? *((end1) - 1) : *((p) - 1)))
247 # define MAKE_CHAR(charset, c1, c2) (c1)
248 #endif /* not emacs */
250 #ifndef RE_TRANSLATE
251 # define RE_TRANSLATE(TBL, C) ((unsigned char)(TBL)[C])
252 # define RE_TRANSLATE_P(TBL) (TBL)
253 #endif
255 /* Get the interface, including the syntax bits. */
256 #include "regex.h"
258 /* isalpha etc. are used for the character classes. */
259 #include <ctype.h>
261 #ifdef emacs
263 /* 1 if C is an ASCII character. */
264 # define IS_REAL_ASCII(c) ((c) < 0200)
266 /* 1 if C is a unibyte character. */
267 # define ISUNIBYTE(c) (SINGLE_BYTE_CHAR_P ((c)))
269 /* The Emacs definitions should not be directly affected by locales. */
271 /* In Emacs, these are only used for single-byte characters. */
272 # define ISDIGIT(c) ((c) >= '0' && (c) <= '9')
273 # define ISCNTRL(c) ((c) < ' ')
274 # define ISXDIGIT(c) (((c) >= '0' && (c) <= '9') \
275 || ((c) >= 'a' && (c) <= 'f') \
276 || ((c) >= 'A' && (c) <= 'F'))
278 /* This is only used for single-byte characters. */
279 # define ISBLANK(c) ((c) == ' ' || (c) == '\t')
281 /* The rest must handle multibyte characters. */
283 # define ISGRAPH(c) (SINGLE_BYTE_CHAR_P (c) \
284 ? (c) > ' ' && !((c) >= 0177 && (c) <= 0237) \
285 : 1)
287 # define ISPRINT(c) (SINGLE_BYTE_CHAR_P (c) \
288 ? (c) >= ' ' && !((c) >= 0177 && (c) <= 0237) \
289 : 1)
291 # define ISALNUM(c) (IS_REAL_ASCII (c) \
292 ? (((c) >= 'a' && (c) <= 'z') \
293 || ((c) >= 'A' && (c) <= 'Z') \
294 || ((c) >= '0' && (c) <= '9')) \
295 : SYNTAX (c) == Sword)
297 # define ISALPHA(c) (IS_REAL_ASCII (c) \
298 ? (((c) >= 'a' && (c) <= 'z') \
299 || ((c) >= 'A' && (c) <= 'Z')) \
300 : SYNTAX (c) == Sword)
302 # define ISLOWER(c) (LOWERCASEP (c))
304 # define ISPUNCT(c) (IS_REAL_ASCII (c) \
305 ? ((c) > ' ' && (c) < 0177 \
306 && !(((c) >= 'a' && (c) <= 'z') \
307 || ((c) >= 'A' && (c) <= 'Z') \
308 || ((c) >= '0' && (c) <= '9'))) \
309 : SYNTAX (c) != Sword)
311 # define ISSPACE(c) (SYNTAX (c) == Swhitespace)
313 # define ISUPPER(c) (UPPERCASEP (c))
315 # define ISWORD(c) (SYNTAX (c) == Sword)
317 #else /* not emacs */
319 /* Jim Meyering writes:
321 "... Some ctype macros are valid only for character codes that
322 isascii says are ASCII (SGI's IRIX-4.0.5 is one such system --when
323 using /bin/cc or gcc but without giving an ansi option). So, all
324 ctype uses should be through macros like ISPRINT... If
325 STDC_HEADERS is defined, then autoconf has verified that the ctype
326 macros don't need to be guarded with references to isascii. ...
327 Defining isascii to 1 should let any compiler worth its salt
328 eliminate the && through constant folding."
329 Solaris defines some of these symbols so we must undefine them first. */
331 # undef ISASCII
332 # if defined STDC_HEADERS || (!defined isascii && !defined HAVE_ISASCII)
333 # define ISASCII(c) 1
334 # else
335 # define ISASCII(c) isascii(c)
336 # endif
338 /* 1 if C is an ASCII character. */
339 # define IS_REAL_ASCII(c) ((c) < 0200)
341 /* This distinction is not meaningful, except in Emacs. */
342 # define ISUNIBYTE(c) 1
344 # ifdef isblank
345 # define ISBLANK(c) (ISASCII (c) && isblank (c))
346 # else
347 # define ISBLANK(c) ((c) == ' ' || (c) == '\t')
348 # endif
349 # ifdef isgraph
350 # define ISGRAPH(c) (ISASCII (c) && isgraph (c))
351 # else
352 # define ISGRAPH(c) (ISASCII (c) && isprint (c) && !isspace (c))
353 # endif
355 # undef ISPRINT
356 # define ISPRINT(c) (ISASCII (c) && isprint (c))
357 # define ISDIGIT(c) (ISASCII (c) && isdigit (c))
358 # define ISALNUM(c) (ISASCII (c) && isalnum (c))
359 # define ISALPHA(c) (ISASCII (c) && isalpha (c))
360 # define ISCNTRL(c) (ISASCII (c) && iscntrl (c))
361 # define ISLOWER(c) (ISASCII (c) && islower (c))
362 # define ISPUNCT(c) (ISASCII (c) && ispunct (c))
363 # define ISSPACE(c) (ISASCII (c) && isspace (c))
364 # define ISUPPER(c) (ISASCII (c) && isupper (c))
365 # define ISXDIGIT(c) (ISASCII (c) && isxdigit (c))
367 # define ISWORD(c) ISALPHA(c)
369 # ifdef _tolower
370 # define TOLOWER(c) _tolower(c)
371 # else
372 # define TOLOWER(c) tolower(c)
373 # endif
375 /* How many characters in the character set. */
376 # define CHAR_SET_SIZE 256
378 # ifdef SYNTAX_TABLE
380 extern char *re_syntax_table;
382 # else /* not SYNTAX_TABLE */
384 static char re_syntax_table[CHAR_SET_SIZE];
386 static void
387 init_syntax_once ()
389 register int c;
390 static int done = 0;
392 if (done)
393 return;
395 bzero (re_syntax_table, sizeof re_syntax_table);
397 for (c = 0; c < CHAR_SET_SIZE; ++c)
398 if (ISALNUM (c))
399 re_syntax_table[c] = Sword;
401 re_syntax_table['_'] = Sword;
403 done = 1;
406 # endif /* not SYNTAX_TABLE */
408 # define SYNTAX(c) re_syntax_table[(c)]
410 #endif /* not emacs */
412 #ifndef NULL
413 # define NULL (void *)0
414 #endif
416 /* We remove any previous definition of `SIGN_EXTEND_CHAR',
417 since ours (we hope) works properly with all combinations of
418 machines, compilers, `char' and `unsigned char' argument types.
419 (Per Bothner suggested the basic approach.) */
420 #undef SIGN_EXTEND_CHAR
421 #if __STDC__
422 # define SIGN_EXTEND_CHAR(c) ((signed char) (c))
423 #else /* not __STDC__ */
424 /* As in Harbison and Steele. */
425 # define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128)
426 #endif
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.
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. */
438 #ifdef REGEX_MALLOC
440 # define REGEX_ALLOCATE malloc
441 # define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
442 # define REGEX_FREE free
444 #else /* not REGEX_MALLOC */
446 /* Emacs already defines alloca, sometimes. */
447 # ifndef alloca
449 /* Make alloca work the best possible way. */
450 # ifdef __GNUC__
451 # define alloca __builtin_alloca
452 # else /* not __GNUC__ */
453 # if HAVE_ALLOCA_H
454 # include <alloca.h>
455 # endif /* HAVE_ALLOCA_H */
456 # endif /* not __GNUC__ */
458 # endif /* not alloca */
460 # define REGEX_ALLOCATE alloca
462 /* Assumes a `char *destination' variable. */
463 # define REGEX_REALLOCATE(source, osize, nsize) \
464 (destination = (char *) alloca (nsize), \
465 memcpy (destination, source, osize))
467 /* No need to do anything to free, after alloca. */
468 # define REGEX_FREE(arg) ((void)0) /* Do nothing! But inhibit gcc warning. */
470 #endif /* not REGEX_MALLOC */
472 /* Define how to allocate the failure stack. */
474 #if defined REL_ALLOC && defined REGEX_MALLOC
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)
483 #else /* not using relocating allocator */
485 # ifdef REGEX_MALLOC
487 # define REGEX_ALLOCATE_STACK malloc
488 # define REGEX_REALLOCATE_STACK(source, osize, nsize) realloc (source, nsize)
489 # define REGEX_FREE_STACK free
491 # else /* not REGEX_MALLOC */
493 # define REGEX_ALLOCATE_STACK alloca
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)
500 # endif /* not REGEX_MALLOC */
501 #endif /* not using relocating allocator */
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)
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 RETALLOC_IF(addr, n, t) \
514 if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
515 #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
517 #define BYTEWIDTH 8 /* In bits. */
519 #define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
521 #undef MAX
522 #undef MIN
523 #define MAX(a, b) ((a) > (b) ? (a) : (b))
524 #define MIN(a, b) ((a) < (b) ? (a) : (b))
526 /* Type of source-pattern and string chars. */
527 typedef const unsigned char re_char;
529 typedef char boolean;
530 #define false 0
531 #define true 1
533 static int re_match_2_internal _RE_ARGS ((struct re_pattern_buffer *bufp,
534 re_char *string1, int size1,
535 re_char *string2, int size2,
536 int pos,
537 struct re_registers *regs,
538 int stop));
540 /* These are the command codes that appear in compiled regular
541 expressions. Some opcodes are followed by argument bytes. A
542 command code can specify any interpretation whatsoever for its
543 arguments. Zero bytes may appear in the compiled regular expression. */
545 typedef enum
547 no_op = 0,
549 /* Succeed right away--no more backtracking. */
550 succeed,
552 /* Followed by one byte giving n, then by n literal bytes. */
553 exactn,
555 /* Matches any (more or less) character. */
556 anychar,
558 /* Matches any one char belonging to specified set. First
559 following byte is number of bitmap bytes. Then come bytes
560 for a bitmap saying which chars are in. Bits in each byte
561 are ordered low-bit-first. A character is in the set if its
562 bit is 1. A character too large to have a bit in the map is
563 automatically not in the set.
565 If the length byte has the 0x80 bit set, then that stuff
566 is followed by a range table:
567 2 bytes of flags for character sets (low 8 bits, high 8 bits)
568 See RANGE_TABLE_WORK_BITS below.
569 2 bytes, the number of pairs that follow (upto 32767)
570 pairs, each 2 multibyte characters,
571 each multibyte character represented as 3 bytes. */
572 charset,
574 /* Same parameters as charset, but match any character that is
575 not one of those specified. */
576 charset_not,
578 /* Start remembering the text that is matched, for storing in a
579 register. Followed by one byte with the register number, in
580 the range 0 to one less than the pattern buffer's re_nsub
581 field. */
582 start_memory,
584 /* Stop remembering the text that is matched and store it in a
585 memory register. Followed by one byte with the register
586 number, in the range 0 to one less than `re_nsub' in the
587 pattern buffer. */
588 stop_memory,
590 /* Match a duplicate of something remembered. Followed by one
591 byte containing the register number. */
592 duplicate,
594 /* Fail unless at beginning of line. */
595 begline,
597 /* Fail unless at end of line. */
598 endline,
600 /* Succeeds if at beginning of buffer (if emacs) or at beginning
601 of string to be matched (if not). */
602 begbuf,
604 /* Analogously, for end of buffer/string. */
605 endbuf,
607 /* Followed by two byte relative address to which to jump. */
608 jump,
610 /* Followed by two-byte relative address of place to resume at
611 in case of failure. */
612 on_failure_jump,
614 /* Like on_failure_jump, but pushes a placeholder instead of the
615 current string position when executed. */
616 on_failure_keep_string_jump,
618 /* Just like `on_failure_jump', except that it checks that we
619 don't get stuck in an infinite loop (matching an empty string
620 indefinitely). */
621 on_failure_jump_loop,
623 /* Just like `on_failure_jump_loop', except that it checks for
624 a different kind of loop (the kind that shows up with non-greedy
625 operators). This operation has to be immediately preceded
626 by a `no_op'. */
627 on_failure_jump_nastyloop,
629 /* A smart `on_failure_jump' used for greedy * and + operators.
630 It analyses the loop before which it is put and if the
631 loop does not require backtracking, it changes itself to
632 `on_failure_keep_string_jump' and short-circuits the loop,
633 else it just defaults to changing itself into `on_failure_jump'.
634 It assumes that it is pointing to just past a `jump'. */
635 on_failure_jump_smart,
637 /* Followed by two-byte relative address and two-byte number n.
638 After matching N times, jump to the address upon failure.
639 Does not work if N starts at 0: use on_failure_jump_loop
640 instead. */
641 succeed_n,
643 /* Followed by two-byte relative address, and two-byte number n.
644 Jump to the address N times, then fail. */
645 jump_n,
647 /* Set the following two-byte relative address to the
648 subsequent two-byte number. The address *includes* the two
649 bytes of number. */
650 set_number_at,
652 wordbeg, /* Succeeds if at word beginning. */
653 wordend, /* Succeeds if at word end. */
655 wordbound, /* Succeeds if at a word boundary. */
656 notwordbound, /* Succeeds if not at a word boundary. */
658 /* Matches any character whose syntax is specified. Followed by
659 a byte which contains a syntax code, e.g., Sword. */
660 syntaxspec,
662 /* Matches any character whose syntax is not that specified. */
663 notsyntaxspec
665 #ifdef emacs
666 ,before_dot, /* Succeeds if before point. */
667 at_dot, /* Succeeds if at point. */
668 after_dot, /* Succeeds if after point. */
670 /* Matches any character whose category-set contains the specified
671 category. The operator is followed by a byte which contains a
672 category code (mnemonic ASCII character). */
673 categoryspec,
675 /* Matches any character whose category-set does not contain the
676 specified category. The operator is followed by a byte which
677 contains the category code (mnemonic ASCII character). */
678 notcategoryspec
679 #endif /* emacs */
680 } re_opcode_t;
682 /* Common operations on the compiled pattern. */
684 /* Store NUMBER in two contiguous bytes starting at DESTINATION. */
686 #define STORE_NUMBER(destination, number) \
687 do { \
688 (destination)[0] = (number) & 0377; \
689 (destination)[1] = (number) >> 8; \
690 } while (0)
692 /* Same as STORE_NUMBER, except increment DESTINATION to
693 the byte after where the number is stored. Therefore, DESTINATION
694 must be an lvalue. */
696 #define STORE_NUMBER_AND_INCR(destination, number) \
697 do { \
698 STORE_NUMBER (destination, number); \
699 (destination) += 2; \
700 } while (0)
702 /* Put into DESTINATION a number stored in two contiguous bytes starting
703 at SOURCE. */
705 #define EXTRACT_NUMBER(destination, source) \
706 do { \
707 (destination) = *(source) & 0377; \
708 (destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8; \
709 } while (0)
711 #ifdef DEBUG
712 static void extract_number _RE_ARGS ((int *dest, re_char *source));
713 static void
714 extract_number (dest, source)
715 int *dest;
716 re_char *source;
718 int temp = SIGN_EXTEND_CHAR (*(source + 1));
719 *dest = *source & 0377;
720 *dest += temp << 8;
723 # ifndef EXTRACT_MACROS /* To debug the macros. */
724 # undef EXTRACT_NUMBER
725 # define EXTRACT_NUMBER(dest, src) extract_number (&dest, src)
726 # endif /* not EXTRACT_MACROS */
728 #endif /* DEBUG */
730 /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
731 SOURCE must be an lvalue. */
733 #define EXTRACT_NUMBER_AND_INCR(destination, source) \
734 do { \
735 EXTRACT_NUMBER (destination, source); \
736 (source) += 2; \
737 } while (0)
739 #ifdef DEBUG
740 static void extract_number_and_incr _RE_ARGS ((int *destination,
741 re_char **source));
742 static void
743 extract_number_and_incr (destination, source)
744 int *destination;
745 re_char **source;
747 extract_number (destination, *source);
748 *source += 2;
751 # ifndef EXTRACT_MACROS
752 # undef EXTRACT_NUMBER_AND_INCR
753 # define EXTRACT_NUMBER_AND_INCR(dest, src) \
754 extract_number_and_incr (&dest, &src)
755 # endif /* not EXTRACT_MACROS */
757 #endif /* DEBUG */
759 /* Store a multibyte character in three contiguous bytes starting
760 DESTINATION, and increment DESTINATION to the byte after where the
761 character is stored. Therefore, DESTINATION must be an lvalue. */
763 #define STORE_CHARACTER_AND_INCR(destination, character) \
764 do { \
765 (destination)[0] = (character) & 0377; \
766 (destination)[1] = ((character) >> 8) & 0377; \
767 (destination)[2] = (character) >> 16; \
768 (destination) += 3; \
769 } while (0)
771 /* Put into DESTINATION a character stored in three contiguous bytes
772 starting at SOURCE. */
774 #define EXTRACT_CHARACTER(destination, source) \
775 do { \
776 (destination) = ((source)[0] \
777 | ((source)[1] << 8) \
778 | ((source)[2] << 16)); \
779 } while (0)
782 /* Macros for charset. */
784 /* Size of bitmap of charset P in bytes. P is a start of charset,
785 i.e. *P is (re_opcode_t) charset or (re_opcode_t) charset_not. */
786 #define CHARSET_BITMAP_SIZE(p) ((p)[1] & 0x7F)
788 /* Nonzero if charset P has range table. */
789 #define CHARSET_RANGE_TABLE_EXISTS_P(p) ((p)[1] & 0x80)
791 /* Return the address of range table of charset P. But not the start
792 of table itself, but the before where the number of ranges is
793 stored. `2 +' means to skip re_opcode_t and size of bitmap,
794 and the 2 bytes of flags at the start of the range table. */
795 #define CHARSET_RANGE_TABLE(p) (&(p)[4 + CHARSET_BITMAP_SIZE (p)])
797 /* Extract the bit flags that start a range table. */
798 #define CHARSET_RANGE_TABLE_BITS(p) \
799 ((p)[2 + CHARSET_BITMAP_SIZE (p)] \
800 + (p)[3 + CHARSET_BITMAP_SIZE (p)] * 0x100)
802 /* Test if C is listed in the bitmap of charset P. */
803 #define CHARSET_LOOKUP_BITMAP(p, c) \
804 ((c) < CHARSET_BITMAP_SIZE (p) * BYTEWIDTH \
805 && (p)[2 + (c) / BYTEWIDTH] & (1 << ((c) % BYTEWIDTH)))
807 /* Return the address of end of RANGE_TABLE. COUNT is number of
808 ranges (which is a pair of (start, end)) in the RANGE_TABLE. `* 2'
809 is start of range and end of range. `* 3' is size of each start
810 and end. */
811 #define CHARSET_RANGE_TABLE_END(range_table, count) \
812 ((range_table) + (count) * 2 * 3)
814 /* Test if C is in RANGE_TABLE. A flag NOT is negated if C is in.
815 COUNT is number of ranges in RANGE_TABLE. */
816 #define CHARSET_LOOKUP_RANGE_TABLE_RAW(not, c, range_table, count) \
817 do \
819 re_wchar_t range_start, range_end; \
820 re_char *p; \
821 re_char *range_table_end \
822 = CHARSET_RANGE_TABLE_END ((range_table), (count)); \
824 for (p = (range_table); p < range_table_end; p += 2 * 3) \
826 EXTRACT_CHARACTER (range_start, p); \
827 EXTRACT_CHARACTER (range_end, p + 3); \
829 if (range_start <= (c) && (c) <= range_end) \
831 (not) = !(not); \
832 break; \
836 while (0)
838 /* Test if C is in range table of CHARSET. The flag NOT is negated if
839 C is listed in it. */
840 #define CHARSET_LOOKUP_RANGE_TABLE(not, c, charset) \
841 do \
843 /* Number of ranges in range table. */ \
844 int count; \
845 re_char *range_table = CHARSET_RANGE_TABLE (charset); \
847 EXTRACT_NUMBER_AND_INCR (count, range_table); \
848 CHARSET_LOOKUP_RANGE_TABLE_RAW ((not), (c), range_table, count); \
850 while (0)
852 /* If DEBUG is defined, Regex prints many voluminous messages about what
853 it is doing (if the variable `debug' is nonzero). If linked with the
854 main program in `iregex.c', you can enter patterns and strings
855 interactively. And if linked with the main program in `main.c' and
856 the other test files, you can run the already-written tests. */
858 #ifdef DEBUG
860 /* We use standard I/O for debugging. */
861 # include <stdio.h>
863 /* It is useful to test things that ``must'' be true when debugging. */
864 # include <assert.h>
866 static int debug = -100000;
868 # define DEBUG_STATEMENT(e) e
869 # define DEBUG_PRINT1(x) if (debug > 0) printf (x)
870 # define DEBUG_PRINT2(x1, x2) if (debug > 0) printf (x1, x2)
871 # define DEBUG_PRINT3(x1, x2, x3) if (debug > 0) printf (x1, x2, x3)
872 # define DEBUG_PRINT4(x1, x2, x3, x4) if (debug > 0) printf (x1, x2, x3, x4)
873 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) \
874 if (debug > 0) print_partial_compiled_pattern (s, e)
875 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) \
876 if (debug > 0) print_double_string (w, s1, sz1, s2, sz2)
879 /* Print the fastmap in human-readable form. */
881 void
882 print_fastmap (fastmap)
883 char *fastmap;
885 unsigned was_a_range = 0;
886 unsigned i = 0;
888 while (i < (1 << BYTEWIDTH))
890 if (fastmap[i++])
892 was_a_range = 0;
893 putchar (i - 1);
894 while (i < (1 << BYTEWIDTH) && fastmap[i])
896 was_a_range = 1;
897 i++;
899 if (was_a_range)
901 printf ("-");
902 putchar (i - 1);
906 putchar ('\n');
910 /* Print a compiled pattern string in human-readable form, starting at
911 the START pointer into it and ending just before the pointer END. */
913 void
914 print_partial_compiled_pattern (start, end)
915 re_char *start;
916 re_char *end;
918 int mcnt, mcnt2;
919 re_char *p = start;
920 re_char *pend = end;
922 if (start == NULL)
924 fprintf (stderr, "(null)\n");
925 return;
928 /* Loop over pattern commands. */
929 while (p < pend)
931 fprintf (stderr, "%d:\t", p - start);
933 switch ((re_opcode_t) *p++)
935 case no_op:
936 fprintf (stderr, "/no_op");
937 break;
939 case succeed:
940 fprintf (stderr, "/succeed");
941 break;
943 case exactn:
944 mcnt = *p++;
945 fprintf (stderr, "/exactn/%d", mcnt);
948 fprintf (stderr, "/%c", *p++);
950 while (--mcnt);
951 break;
953 case start_memory:
954 fprintf (stderr, "/start_memory/%d", *p++);
955 break;
957 case stop_memory:
958 fprintf (stderr, "/stop_memory/%d", *p++);
959 break;
961 case duplicate:
962 fprintf (stderr, "/duplicate/%d", *p++);
963 break;
965 case anychar:
966 fprintf (stderr, "/anychar");
967 break;
969 case charset:
970 case charset_not:
972 register int c, last = -100;
973 register int in_range = 0;
974 int length = CHARSET_BITMAP_SIZE (p - 1);
975 int has_range_table = CHARSET_RANGE_TABLE_EXISTS_P (p - 1);
977 fprintf (stderr, "/charset [%s",
978 (re_opcode_t) *(p - 1) == charset_not ? "^" : "");
980 assert (p + *p < pend);
982 for (c = 0; c < 256; c++)
983 if (c / 8 < length
984 && (p[1 + (c/8)] & (1 << (c % 8))))
986 /* Are we starting a range? */
987 if (last + 1 == c && ! in_range)
989 fprintf (stderr, "-");
990 in_range = 1;
992 /* Have we broken a range? */
993 else if (last + 1 != c && in_range)
995 fprintf (stderr, "%c", last);
996 in_range = 0;
999 if (! in_range)
1000 fprintf (stderr, "%c", c);
1002 last = c;
1005 if (in_range)
1006 fprintf (stderr, "%c", last);
1008 fprintf (stderr, "]");
1010 p += 1 + length;
1012 if (has_range_table)
1014 int count;
1015 fprintf (stderr, "has-range-table");
1017 /* ??? Should print the range table; for now, just skip it. */
1018 p += 2; /* skip range table bits */
1019 EXTRACT_NUMBER_AND_INCR (count, p);
1020 p = CHARSET_RANGE_TABLE_END (p, count);
1023 break;
1025 case begline:
1026 fprintf (stderr, "/begline");
1027 break;
1029 case endline:
1030 fprintf (stderr, "/endline");
1031 break;
1033 case on_failure_jump:
1034 extract_number_and_incr (&mcnt, &p);
1035 fprintf (stderr, "/on_failure_jump to %d", p + mcnt - start);
1036 break;
1038 case on_failure_keep_string_jump:
1039 extract_number_and_incr (&mcnt, &p);
1040 fprintf (stderr, "/on_failure_keep_string_jump to %d", p + mcnt - start);
1041 break;
1043 case on_failure_jump_nastyloop:
1044 extract_number_and_incr (&mcnt, &p);
1045 fprintf (stderr, "/on_failure_jump_nastyloop to %d", p + mcnt - start);
1046 break;
1048 case on_failure_jump_loop:
1049 extract_number_and_incr (&mcnt, &p);
1050 fprintf (stderr, "/on_failure_jump_loop to %d", p + mcnt - start);
1051 break;
1053 case on_failure_jump_smart:
1054 extract_number_and_incr (&mcnt, &p);
1055 fprintf (stderr, "/on_failure_jump_smart to %d", p + mcnt - start);
1056 break;
1058 case jump:
1059 extract_number_and_incr (&mcnt, &p);
1060 fprintf (stderr, "/jump to %d", p + mcnt - start);
1061 break;
1063 case succeed_n:
1064 extract_number_and_incr (&mcnt, &p);
1065 extract_number_and_incr (&mcnt2, &p);
1066 fprintf (stderr, "/succeed_n to %d, %d times", p - 2 + mcnt - start, mcnt2);
1067 break;
1069 case jump_n:
1070 extract_number_and_incr (&mcnt, &p);
1071 extract_number_and_incr (&mcnt2, &p);
1072 fprintf (stderr, "/jump_n to %d, %d times", p - 2 + mcnt - start, mcnt2);
1073 break;
1075 case set_number_at:
1076 extract_number_and_incr (&mcnt, &p);
1077 extract_number_and_incr (&mcnt2, &p);
1078 fprintf (stderr, "/set_number_at location %d to %d", p - 2 + mcnt - start, mcnt2);
1079 break;
1081 case wordbound:
1082 fprintf (stderr, "/wordbound");
1083 break;
1085 case notwordbound:
1086 fprintf (stderr, "/notwordbound");
1087 break;
1089 case wordbeg:
1090 fprintf (stderr, "/wordbeg");
1091 break;
1093 case wordend:
1094 fprintf (stderr, "/wordend");
1096 case syntaxspec:
1097 fprintf (stderr, "/syntaxspec");
1098 mcnt = *p++;
1099 fprintf (stderr, "/%d", mcnt);
1100 break;
1102 case notsyntaxspec:
1103 fprintf (stderr, "/notsyntaxspec");
1104 mcnt = *p++;
1105 fprintf (stderr, "/%d", mcnt);
1106 break;
1108 # ifdef emacs
1109 case before_dot:
1110 fprintf (stderr, "/before_dot");
1111 break;
1113 case at_dot:
1114 fprintf (stderr, "/at_dot");
1115 break;
1117 case after_dot:
1118 fprintf (stderr, "/after_dot");
1119 break;
1121 case categoryspec:
1122 fprintf (stderr, "/categoryspec");
1123 mcnt = *p++;
1124 fprintf (stderr, "/%d", mcnt);
1125 break;
1127 case notcategoryspec:
1128 fprintf (stderr, "/notcategoryspec");
1129 mcnt = *p++;
1130 fprintf (stderr, "/%d", mcnt);
1131 break;
1132 # endif /* emacs */
1134 case begbuf:
1135 fprintf (stderr, "/begbuf");
1136 break;
1138 case endbuf:
1139 fprintf (stderr, "/endbuf");
1140 break;
1142 default:
1143 fprintf (stderr, "?%d", *(p-1));
1146 fprintf (stderr, "\n");
1149 fprintf (stderr, "%d:\tend of pattern.\n", p - start);
1153 void
1154 print_compiled_pattern (bufp)
1155 struct re_pattern_buffer *bufp;
1157 re_char *buffer = bufp->buffer;
1159 print_partial_compiled_pattern (buffer, buffer + bufp->used);
1160 printf ("%ld bytes used/%ld bytes allocated.\n",
1161 bufp->used, bufp->allocated);
1163 if (bufp->fastmap_accurate && bufp->fastmap)
1165 printf ("fastmap: ");
1166 print_fastmap (bufp->fastmap);
1169 printf ("re_nsub: %d\t", bufp->re_nsub);
1170 printf ("regs_alloc: %d\t", bufp->regs_allocated);
1171 printf ("can_be_null: %d\t", bufp->can_be_null);
1172 printf ("no_sub: %d\t", bufp->no_sub);
1173 printf ("not_bol: %d\t", bufp->not_bol);
1174 printf ("not_eol: %d\t", bufp->not_eol);
1175 printf ("syntax: %lx\n", bufp->syntax);
1176 fflush (stdout);
1177 /* Perhaps we should print the translate table? */
1181 void
1182 print_double_string (where, string1, size1, string2, size2)
1183 re_char *where;
1184 re_char *string1;
1185 re_char *string2;
1186 int size1;
1187 int size2;
1189 int this_char;
1191 if (where == NULL)
1192 printf ("(null)");
1193 else
1195 if (FIRST_STRING_P (where))
1197 for (this_char = where - string1; this_char < size1; this_char++)
1198 putchar (string1[this_char]);
1200 where = string2;
1203 for (this_char = where - string2; this_char < size2; this_char++)
1204 putchar (string2[this_char]);
1208 #else /* not DEBUG */
1210 # undef assert
1211 # define assert(e)
1213 # define DEBUG_STATEMENT(e)
1214 # define DEBUG_PRINT1(x)
1215 # define DEBUG_PRINT2(x1, x2)
1216 # define DEBUG_PRINT3(x1, x2, x3)
1217 # define DEBUG_PRINT4(x1, x2, x3, x4)
1218 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
1219 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
1221 #endif /* not DEBUG */
1223 /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
1224 also be assigned to arbitrarily: each pattern buffer stores its own
1225 syntax, so it can be changed between regex compilations. */
1226 /* This has no initializer because initialized variables in Emacs
1227 become read-only after dumping. */
1228 reg_syntax_t re_syntax_options;
1231 /* Specify the precise syntax of regexps for compilation. This provides
1232 for compatibility for various utilities which historically have
1233 different, incompatible syntaxes.
1235 The argument SYNTAX is a bit mask comprised of the various bits
1236 defined in regex.h. We return the old syntax. */
1238 reg_syntax_t
1239 re_set_syntax (syntax)
1240 reg_syntax_t syntax;
1242 reg_syntax_t ret = re_syntax_options;
1244 re_syntax_options = syntax;
1245 return ret;
1247 WEAK_ALIAS (__re_set_syntax, re_set_syntax)
1249 /* This table gives an error message for each of the error codes listed
1250 in regex.h. Obviously the order here has to be same as there.
1251 POSIX doesn't require that we do anything for REG_NOERROR,
1252 but why not be nice? */
1254 static const char *re_error_msgid[] =
1256 gettext_noop ("Success"), /* REG_NOERROR */
1257 gettext_noop ("No match"), /* REG_NOMATCH */
1258 gettext_noop ("Invalid regular expression"), /* REG_BADPAT */
1259 gettext_noop ("Invalid collation character"), /* REG_ECOLLATE */
1260 gettext_noop ("Invalid character class name"), /* REG_ECTYPE */
1261 gettext_noop ("Trailing backslash"), /* REG_EESCAPE */
1262 gettext_noop ("Invalid back reference"), /* REG_ESUBREG */
1263 gettext_noop ("Unmatched [ or [^"), /* REG_EBRACK */
1264 gettext_noop ("Unmatched ( or \\("), /* REG_EPAREN */
1265 gettext_noop ("Unmatched \\{"), /* REG_EBRACE */
1266 gettext_noop ("Invalid content of \\{\\}"), /* REG_BADBR */
1267 gettext_noop ("Invalid range end"), /* REG_ERANGE */
1268 gettext_noop ("Memory exhausted"), /* REG_ESPACE */
1269 gettext_noop ("Invalid preceding regular expression"), /* REG_BADRPT */
1270 gettext_noop ("Premature end of regular expression"), /* REG_EEND */
1271 gettext_noop ("Regular expression too big"), /* REG_ESIZE */
1272 gettext_noop ("Unmatched ) or \\)"), /* REG_ERPAREN */
1275 /* Avoiding alloca during matching, to placate r_alloc. */
1277 /* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
1278 searching and matching functions should not call alloca. On some
1279 systems, alloca is implemented in terms of malloc, and if we're
1280 using the relocating allocator routines, then malloc could cause a
1281 relocation, which might (if the strings being searched are in the
1282 ralloc heap) shift the data out from underneath the regexp
1283 routines.
1285 Here's another reason to avoid allocation: Emacs
1286 processes input from X in a signal handler; processing X input may
1287 call malloc; if input arrives while a matching routine is calling
1288 malloc, then we're scrod. But Emacs can't just block input while
1289 calling matching routines; then we don't notice interrupts when
1290 they come in. So, Emacs blocks input around all regexp calls
1291 except the matching calls, which it leaves unprotected, in the
1292 faith that they will not malloc. */
1294 /* Normally, this is fine. */
1295 #define MATCH_MAY_ALLOCATE
1297 /* When using GNU C, we are not REALLY using the C alloca, no matter
1298 what config.h may say. So don't take precautions for it. */
1299 #ifdef __GNUC__
1300 # undef C_ALLOCA
1301 #endif
1303 /* The match routines may not allocate if (1) they would do it with malloc
1304 and (2) it's not safe for them to use malloc.
1305 Note that if REL_ALLOC is defined, matching would not use malloc for the
1306 failure stack, but we would still use it for the register vectors;
1307 so REL_ALLOC should not affect this. */
1308 #if (defined C_ALLOCA || defined REGEX_MALLOC) && defined emacs
1309 # undef MATCH_MAY_ALLOCATE
1310 #endif
1313 /* Failure stack declarations and macros; both re_compile_fastmap and
1314 re_match_2 use a failure stack. These have to be macros because of
1315 REGEX_ALLOCATE_STACK. */
1318 /* Approximate number of failure points for which to initially allocate space
1319 when matching. If this number is exceeded, we allocate more
1320 space, so it is not a hard limit. */
1321 #ifndef INIT_FAILURE_ALLOC
1322 # define INIT_FAILURE_ALLOC 20
1323 #endif
1325 /* Roughly the maximum number of failure points on the stack. Would be
1326 exactly that if always used TYPICAL_FAILURE_SIZE items each time we failed.
1327 This is a variable only so users of regex can assign to it; we never
1328 change it ourselves. We always multiply it by TYPICAL_FAILURE_SIZE
1329 before using it, so it should probably be a byte-count instead. */
1330 # if defined MATCH_MAY_ALLOCATE
1331 /* Note that 4400 was enough to cause a crash on Alpha OSF/1,
1332 whose default stack limit is 2mb. In order for a larger
1333 value to work reliably, you have to try to make it accord
1334 with the process stack limit. */
1335 size_t re_max_failures = 40000;
1336 # else
1337 size_t re_max_failures = 4000;
1338 # endif
1340 union fail_stack_elt
1342 re_char *pointer;
1343 /* This should be the biggest `int' that's no bigger than a pointer. */
1344 long integer;
1347 typedef union fail_stack_elt fail_stack_elt_t;
1349 typedef struct
1351 fail_stack_elt_t *stack;
1352 size_t size;
1353 size_t avail; /* Offset of next open position. */
1354 size_t frame; /* Offset of the cur constructed frame. */
1355 } fail_stack_type;
1357 #define FAIL_STACK_EMPTY() (fail_stack.frame == 0)
1358 #define FAIL_STACK_FULL() (fail_stack.avail == fail_stack.size)
1361 /* Define macros to initialize and free the failure stack.
1362 Do `return -2' if the alloc fails. */
1364 #ifdef MATCH_MAY_ALLOCATE
1365 # define INIT_FAIL_STACK() \
1366 do { \
1367 fail_stack.stack = (fail_stack_elt_t *) \
1368 REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * TYPICAL_FAILURE_SIZE \
1369 * sizeof (fail_stack_elt_t)); \
1371 if (fail_stack.stack == NULL) \
1372 return -2; \
1374 fail_stack.size = INIT_FAILURE_ALLOC; \
1375 fail_stack.avail = 0; \
1376 fail_stack.frame = 0; \
1377 } while (0)
1379 # define RESET_FAIL_STACK() REGEX_FREE_STACK (fail_stack.stack)
1380 #else
1381 # define INIT_FAIL_STACK() \
1382 do { \
1383 fail_stack.avail = 0; \
1384 fail_stack.frame = 0; \
1385 } while (0)
1387 # define RESET_FAIL_STACK() ((void)0)
1388 #endif
1391 /* Double the size of FAIL_STACK, up to a limit
1392 which allows approximately `re_max_failures' items.
1394 Return 1 if succeeds, and 0 if either ran out of memory
1395 allocating space for it or it was already too large.
1397 REGEX_REALLOCATE_STACK requires `destination' be declared. */
1399 /* Factor to increase the failure stack size by
1400 when we increase it.
1401 This used to be 2, but 2 was too wasteful
1402 because the old discarded stacks added up to as much space
1403 were as ultimate, maximum-size stack. */
1404 #define FAIL_STACK_GROWTH_FACTOR 4
1406 #define GROW_FAIL_STACK(fail_stack) \
1407 (((fail_stack).size * sizeof (fail_stack_elt_t) \
1408 >= re_max_failures * TYPICAL_FAILURE_SIZE) \
1409 ? 0 \
1410 : ((fail_stack).stack \
1411 = (fail_stack_elt_t *) \
1412 REGEX_REALLOCATE_STACK ((fail_stack).stack, \
1413 (fail_stack).size * sizeof (fail_stack_elt_t), \
1414 MIN (re_max_failures * TYPICAL_FAILURE_SIZE, \
1415 ((fail_stack).size * sizeof (fail_stack_elt_t) \
1416 * FAIL_STACK_GROWTH_FACTOR))), \
1418 (fail_stack).stack == NULL \
1419 ? 0 \
1420 : ((fail_stack).size \
1421 = (MIN (re_max_failures * TYPICAL_FAILURE_SIZE, \
1422 ((fail_stack).size * sizeof (fail_stack_elt_t) \
1423 * FAIL_STACK_GROWTH_FACTOR)) \
1424 / sizeof (fail_stack_elt_t)), \
1425 1)))
1428 /* Push a pointer value onto the failure stack.
1429 Assumes the variable `fail_stack'. Probably should only
1430 be called from within `PUSH_FAILURE_POINT'. */
1431 #define PUSH_FAILURE_POINTER(item) \
1432 fail_stack.stack[fail_stack.avail++].pointer = (item)
1434 /* This pushes an integer-valued item onto the failure stack.
1435 Assumes the variable `fail_stack'. Probably should only
1436 be called from within `PUSH_FAILURE_POINT'. */
1437 #define PUSH_FAILURE_INT(item) \
1438 fail_stack.stack[fail_stack.avail++].integer = (item)
1440 /* Push a fail_stack_elt_t value onto the failure stack.
1441 Assumes the variable `fail_stack'. Probably should only
1442 be called from within `PUSH_FAILURE_POINT'. */
1443 #define PUSH_FAILURE_ELT(item) \
1444 fail_stack.stack[fail_stack.avail++] = (item)
1446 /* These three POP... operations complement the three PUSH... operations.
1447 All assume that `fail_stack' is nonempty. */
1448 #define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
1449 #define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
1450 #define POP_FAILURE_ELT() fail_stack.stack[--fail_stack.avail]
1452 /* Individual items aside from the registers. */
1453 #define NUM_NONREG_ITEMS 3
1455 /* Used to examine the stack (to detect infinite loops). */
1456 #define FAILURE_PAT(h) fail_stack.stack[(h) - 1].pointer
1457 #define FAILURE_STR(h) (fail_stack.stack[(h) - 2].pointer)
1458 #define NEXT_FAILURE_HANDLE(h) fail_stack.stack[(h) - 3].integer
1459 #define TOP_FAILURE_HANDLE() fail_stack.frame
1462 #define ENSURE_FAIL_STACK(space) \
1463 while (REMAINING_AVAIL_SLOTS <= space) { \
1464 if (!GROW_FAIL_STACK (fail_stack)) \
1465 return -2; \
1466 DEBUG_PRINT2 ("\n Doubled stack; size now: %d\n", (fail_stack).size);\
1467 DEBUG_PRINT2 (" slots available: %d\n", REMAINING_AVAIL_SLOTS);\
1470 /* Push register NUM onto the stack. */
1471 #define PUSH_FAILURE_REG(num) \
1472 do { \
1473 char *destination; \
1474 ENSURE_FAIL_STACK(3); \
1475 DEBUG_PRINT4 (" Push reg %d (spanning %p -> %p)\n", \
1476 num, regstart[num], regend[num]); \
1477 PUSH_FAILURE_POINTER (regstart[num]); \
1478 PUSH_FAILURE_POINTER (regend[num]); \
1479 PUSH_FAILURE_INT (num); \
1480 } while (0)
1482 /* Change the counter's value to VAL, but make sure that it will
1483 be reset when backtracking. */
1484 #define PUSH_NUMBER(ptr,val) \
1485 do { \
1486 char *destination; \
1487 int c; \
1488 ENSURE_FAIL_STACK(3); \
1489 EXTRACT_NUMBER (c, ptr); \
1490 DEBUG_PRINT4 (" Push number %p = %d -> %d\n", ptr, c, val); \
1491 PUSH_FAILURE_INT (c); \
1492 PUSH_FAILURE_POINTER (ptr); \
1493 PUSH_FAILURE_INT (-1); \
1494 STORE_NUMBER (ptr, val); \
1495 } while (0)
1497 /* Pop a saved register off the stack. */
1498 #define POP_FAILURE_REG_OR_COUNT() \
1499 do { \
1500 int reg = POP_FAILURE_INT (); \
1501 if (reg == -1) \
1503 /* It's a counter. */ \
1504 /* Here, we discard `const', making re_match non-reentrant. */ \
1505 unsigned char *ptr = (unsigned char*) POP_FAILURE_POINTER (); \
1506 reg = POP_FAILURE_INT (); \
1507 STORE_NUMBER (ptr, reg); \
1508 DEBUG_PRINT3 (" Pop counter %p = %d\n", ptr, reg); \
1510 else \
1512 regend[reg] = POP_FAILURE_POINTER (); \
1513 regstart[reg] = POP_FAILURE_POINTER (); \
1514 DEBUG_PRINT4 (" Pop reg %d (spanning %p -> %p)\n", \
1515 reg, regstart[reg], regend[reg]); \
1517 } while (0)
1519 /* Check that we are not stuck in an infinite loop. */
1520 #define CHECK_INFINITE_LOOP(pat_cur, string_place) \
1521 do { \
1522 int failure = TOP_FAILURE_HANDLE (); \
1523 /* Check for infinite matching loops */ \
1524 while (failure > 0 \
1525 && (FAILURE_STR (failure) == string_place \
1526 || FAILURE_STR (failure) == NULL)) \
1528 assert (FAILURE_PAT (failure) >= bufp->buffer \
1529 && FAILURE_PAT (failure) <= bufp->buffer + bufp->used); \
1530 if (FAILURE_PAT (failure) == pat_cur) \
1532 cycle = 1; \
1533 break; \
1535 DEBUG_PRINT2 (" Other pattern: %p\n", FAILURE_PAT (failure)); \
1536 failure = NEXT_FAILURE_HANDLE(failure); \
1538 DEBUG_PRINT2 (" Other string: %p\n", FAILURE_STR (failure)); \
1539 } while (0)
1541 /* Push the information about the state we will need
1542 if we ever fail back to it.
1544 Requires variables fail_stack, regstart, regend and
1545 num_regs be declared. GROW_FAIL_STACK requires `destination' be
1546 declared.
1548 Does `return FAILURE_CODE' if runs out of memory. */
1550 #define PUSH_FAILURE_POINT(pattern, string_place) \
1551 do { \
1552 char *destination; \
1553 /* Must be int, so when we don't save any registers, the arithmetic \
1554 of 0 + -1 isn't done as unsigned. */ \
1556 DEBUG_STATEMENT (nfailure_points_pushed++); \
1557 DEBUG_PRINT1 ("\nPUSH_FAILURE_POINT:\n"); \
1558 DEBUG_PRINT2 (" Before push, next avail: %d\n", (fail_stack).avail); \
1559 DEBUG_PRINT2 (" size: %d\n", (fail_stack).size);\
1561 ENSURE_FAIL_STACK (NUM_NONREG_ITEMS); \
1563 DEBUG_PRINT1 ("\n"); \
1565 DEBUG_PRINT2 (" Push frame index: %d\n", fail_stack.frame); \
1566 PUSH_FAILURE_INT (fail_stack.frame); \
1568 DEBUG_PRINT2 (" Push string %p: `", string_place); \
1569 DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2, size2);\
1570 DEBUG_PRINT1 ("'\n"); \
1571 PUSH_FAILURE_POINTER (string_place); \
1573 DEBUG_PRINT2 (" Push pattern %p: ", pattern); \
1574 DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern, pend); \
1575 PUSH_FAILURE_POINTER (pattern); \
1577 /* Close the frame by moving the frame pointer past it. */ \
1578 fail_stack.frame = fail_stack.avail; \
1579 } while (0)
1581 /* Estimate the size of data pushed by a typical failure stack entry.
1582 An estimate is all we need, because all we use this for
1583 is to choose a limit for how big to make the failure stack. */
1584 /* BEWARE, the value `20' is hard-coded in emacs.c:main(). */
1585 #define TYPICAL_FAILURE_SIZE 20
1587 /* How many items can still be added to the stack without overflowing it. */
1588 #define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
1591 /* Pops what PUSH_FAIL_STACK pushes.
1593 We restore into the parameters, all of which should be lvalues:
1594 STR -- the saved data position.
1595 PAT -- the saved pattern position.
1596 REGSTART, REGEND -- arrays of string positions.
1598 Also assumes the variables `fail_stack' and (if debugging), `bufp',
1599 `pend', `string1', `size1', `string2', and `size2'. */
1601 #define POP_FAILURE_POINT(str, pat) \
1602 do { \
1603 assert (!FAIL_STACK_EMPTY ()); \
1605 /* Remove failure points and point to how many regs pushed. */ \
1606 DEBUG_PRINT1 ("POP_FAILURE_POINT:\n"); \
1607 DEBUG_PRINT2 (" Before pop, next avail: %d\n", fail_stack.avail); \
1608 DEBUG_PRINT2 (" size: %d\n", fail_stack.size); \
1610 /* Pop the saved registers. */ \
1611 while (fail_stack.frame < fail_stack.avail) \
1612 POP_FAILURE_REG_OR_COUNT (); \
1614 pat = POP_FAILURE_POINTER (); \
1615 DEBUG_PRINT2 (" Popping pattern %p: ", pat); \
1616 DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend); \
1618 /* If the saved string location is NULL, it came from an \
1619 on_failure_keep_string_jump opcode, and we want to throw away the \
1620 saved NULL, thus retaining our current position in the string. */ \
1621 str = POP_FAILURE_POINTER (); \
1622 DEBUG_PRINT2 (" Popping string %p: `", str); \
1623 DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2); \
1624 DEBUG_PRINT1 ("'\n"); \
1626 fail_stack.frame = POP_FAILURE_INT (); \
1627 DEBUG_PRINT2 (" Popping frame index: %d\n", fail_stack.frame); \
1629 assert (fail_stack.avail >= 0); \
1630 assert (fail_stack.frame <= fail_stack.avail); \
1632 DEBUG_STATEMENT (nfailure_points_popped++); \
1633 } while (0) /* POP_FAILURE_POINT */
1637 /* Registers are set to a sentinel when they haven't yet matched. */
1638 #define REG_UNSET(e) ((e) == NULL)
1640 /* Subroutine declarations and macros for regex_compile. */
1642 static reg_errcode_t regex_compile _RE_ARGS ((re_char *pattern, size_t size,
1643 reg_syntax_t syntax,
1644 struct re_pattern_buffer *bufp));
1645 static void store_op1 _RE_ARGS ((re_opcode_t op, unsigned char *loc, int arg));
1646 static void store_op2 _RE_ARGS ((re_opcode_t op, unsigned char *loc,
1647 int arg1, int arg2));
1648 static void insert_op1 _RE_ARGS ((re_opcode_t op, unsigned char *loc,
1649 int arg, unsigned char *end));
1650 static void insert_op2 _RE_ARGS ((re_opcode_t op, unsigned char *loc,
1651 int arg1, int arg2, unsigned char *end));
1652 static boolean at_begline_loc_p _RE_ARGS ((re_char *pattern,
1653 re_char *p,
1654 reg_syntax_t syntax));
1655 static boolean at_endline_loc_p _RE_ARGS ((re_char *p,
1656 re_char *pend,
1657 reg_syntax_t syntax));
1658 static re_char *skip_one_char _RE_ARGS ((re_char *p));
1659 static int analyse_first _RE_ARGS ((re_char *p, re_char *pend,
1660 char *fastmap, const int multibyte));
1662 /* Fetch the next character in the uncompiled pattern, with no
1663 translation. */
1664 #define PATFETCH(c) \
1665 do { \
1666 int len; \
1667 if (p == pend) return REG_EEND; \
1668 c = RE_STRING_CHAR_AND_LENGTH (p, pend - p, len); \
1669 p += len; \
1670 } while (0)
1673 /* If `translate' is non-null, return translate[D], else just D. We
1674 cast the subscript to translate because some data is declared as
1675 `char *', to avoid warnings when a string constant is passed. But
1676 when we use a character as a subscript we must make it unsigned. */
1677 #ifndef TRANSLATE
1678 # define TRANSLATE(d) \
1679 (RE_TRANSLATE_P (translate) ? RE_TRANSLATE (translate, (d)) : (d))
1680 #endif
1683 /* Macros for outputting the compiled pattern into `buffer'. */
1685 /* If the buffer isn't allocated when it comes in, use this. */
1686 #define INIT_BUF_SIZE 32
1688 /* Make sure we have at least N more bytes of space in buffer. */
1689 #define GET_BUFFER_SPACE(n) \
1690 while ((size_t) (b - bufp->buffer + (n)) > bufp->allocated) \
1691 EXTEND_BUFFER ()
1693 /* Make sure we have one more byte of buffer space and then add C to it. */
1694 #define BUF_PUSH(c) \
1695 do { \
1696 GET_BUFFER_SPACE (1); \
1697 *b++ = (unsigned char) (c); \
1698 } while (0)
1701 /* Ensure we have two more bytes of buffer space and then append C1 and C2. */
1702 #define BUF_PUSH_2(c1, c2) \
1703 do { \
1704 GET_BUFFER_SPACE (2); \
1705 *b++ = (unsigned char) (c1); \
1706 *b++ = (unsigned char) (c2); \
1707 } while (0)
1710 /* As with BUF_PUSH_2, except for three bytes. */
1711 #define BUF_PUSH_3(c1, c2, c3) \
1712 do { \
1713 GET_BUFFER_SPACE (3); \
1714 *b++ = (unsigned char) (c1); \
1715 *b++ = (unsigned char) (c2); \
1716 *b++ = (unsigned char) (c3); \
1717 } while (0)
1720 /* Store a jump with opcode OP at LOC to location TO. We store a
1721 relative address offset by the three bytes the jump itself occupies. */
1722 #define STORE_JUMP(op, loc, to) \
1723 store_op1 (op, loc, (to) - (loc) - 3)
1725 /* Likewise, for a two-argument jump. */
1726 #define STORE_JUMP2(op, loc, to, arg) \
1727 store_op2 (op, loc, (to) - (loc) - 3, arg)
1729 /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
1730 #define INSERT_JUMP(op, loc, to) \
1731 insert_op1 (op, loc, (to) - (loc) - 3, b)
1733 /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
1734 #define INSERT_JUMP2(op, loc, to, arg) \
1735 insert_op2 (op, loc, (to) - (loc) - 3, arg, b)
1738 /* This is not an arbitrary limit: the arguments which represent offsets
1739 into the pattern are two bytes long. So if 2^16 bytes turns out to
1740 be too small, many things would have to change. */
1741 /* Any other compiler which, like MSC, has allocation limit below 2^16
1742 bytes will have to use approach similar to what was done below for
1743 MSC and drop MAX_BUF_SIZE a bit. Otherwise you may end up
1744 reallocating to 0 bytes. Such thing is not going to work too well.
1745 You have been warned!! */
1746 #if defined _MSC_VER && !defined WIN32
1747 /* Microsoft C 16-bit versions limit malloc to approx 65512 bytes. */
1748 # define MAX_BUF_SIZE 65500L
1749 #else
1750 # define MAX_BUF_SIZE (1L << 16)
1751 #endif
1753 /* Extend the buffer by twice its current size via realloc and
1754 reset the pointers that pointed into the old block to point to the
1755 correct places in the new one. If extending the buffer results in it
1756 being larger than MAX_BUF_SIZE, then flag memory exhausted. */
1757 #if __BOUNDED_POINTERS__
1758 # define SET_HIGH_BOUND(P) (__ptrhigh (P) = __ptrlow (P) + bufp->allocated)
1759 # define MOVE_BUFFER_POINTER(P) \
1760 (__ptrlow (P) += incr, SET_HIGH_BOUND (P), __ptrvalue (P) += incr)
1761 # define ELSE_EXTEND_BUFFER_HIGH_BOUND \
1762 else \
1764 SET_HIGH_BOUND (b); \
1765 SET_HIGH_BOUND (begalt); \
1766 if (fixup_alt_jump) \
1767 SET_HIGH_BOUND (fixup_alt_jump); \
1768 if (laststart) \
1769 SET_HIGH_BOUND (laststart); \
1770 if (pending_exact) \
1771 SET_HIGH_BOUND (pending_exact); \
1773 #else
1774 # define MOVE_BUFFER_POINTER(P) (P) += incr
1775 # define ELSE_EXTEND_BUFFER_HIGH_BOUND
1776 #endif
1777 #define EXTEND_BUFFER() \
1778 do { \
1779 re_char *old_buffer = bufp->buffer; \
1780 if (bufp->allocated == MAX_BUF_SIZE) \
1781 return REG_ESIZE; \
1782 bufp->allocated <<= 1; \
1783 if (bufp->allocated > MAX_BUF_SIZE) \
1784 bufp->allocated = MAX_BUF_SIZE; \
1785 RETALLOC (bufp->buffer, bufp->allocated, unsigned char); \
1786 if (bufp->buffer == NULL) \
1787 return REG_ESPACE; \
1788 /* If the buffer moved, move all the pointers into it. */ \
1789 if (old_buffer != bufp->buffer) \
1791 int incr = bufp->buffer - old_buffer; \
1792 MOVE_BUFFER_POINTER (b); \
1793 MOVE_BUFFER_POINTER (begalt); \
1794 if (fixup_alt_jump) \
1795 MOVE_BUFFER_POINTER (fixup_alt_jump); \
1796 if (laststart) \
1797 MOVE_BUFFER_POINTER (laststart); \
1798 if (pending_exact) \
1799 MOVE_BUFFER_POINTER (pending_exact); \
1801 ELSE_EXTEND_BUFFER_HIGH_BOUND \
1802 } while (0)
1805 /* Since we have one byte reserved for the register number argument to
1806 {start,stop}_memory, the maximum number of groups we can report
1807 things about is what fits in that byte. */
1808 #define MAX_REGNUM 255
1810 /* But patterns can have more than `MAX_REGNUM' registers. We just
1811 ignore the excess. */
1812 typedef int regnum_t;
1815 /* Macros for the compile stack. */
1817 /* Since offsets can go either forwards or backwards, this type needs to
1818 be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
1819 /* int may be not enough when sizeof(int) == 2. */
1820 typedef long pattern_offset_t;
1822 typedef struct
1824 pattern_offset_t begalt_offset;
1825 pattern_offset_t fixup_alt_jump;
1826 pattern_offset_t laststart_offset;
1827 regnum_t regnum;
1828 } compile_stack_elt_t;
1831 typedef struct
1833 compile_stack_elt_t *stack;
1834 unsigned size;
1835 unsigned avail; /* Offset of next open position. */
1836 } compile_stack_type;
1839 #define INIT_COMPILE_STACK_SIZE 32
1841 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
1842 #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
1844 /* The next available element. */
1845 #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
1847 /* Explicit quit checking is only used on NTemacs. */
1848 #if defined WINDOWSNT && defined emacs && defined QUIT
1849 extern int immediate_quit;
1850 # define IMMEDIATE_QUIT_CHECK \
1851 do { \
1852 if (immediate_quit) QUIT; \
1853 } while (0)
1854 #else
1855 # define IMMEDIATE_QUIT_CHECK ((void)0)
1856 #endif
1858 /* Structure to manage work area for range table. */
1859 struct range_table_work_area
1861 int *table; /* actual work area. */
1862 int allocated; /* allocated size for work area in bytes. */
1863 int used; /* actually used size in words. */
1864 int bits; /* flag to record character classes */
1867 /* Make sure that WORK_AREA can hold more N multibyte characters.
1868 This is used only in set_image_of_range and set_image_of_range_1.
1869 It expects WORK_AREA to be a pointer.
1870 If it can't get the space, it returns from the surrounding function. */
1872 #define EXTEND_RANGE_TABLE(work_area, n) \
1873 do { \
1874 if (((work_area)->used + (n)) * sizeof (int) > (work_area)->allocated) \
1876 extend_range_table_work_area (work_area); \
1877 if ((work_area)->table == 0) \
1878 return (REG_ESPACE); \
1880 } while (0)
1882 #define SET_RANGE_TABLE_WORK_AREA_BIT(work_area, bit) \
1883 (work_area).bits |= (bit)
1885 /* Bits used to implement the multibyte-part of the various character classes
1886 such as [:alnum:] in a charset's range table. */
1887 #define BIT_WORD 0x1
1888 #define BIT_LOWER 0x2
1889 #define BIT_PUNCT 0x4
1890 #define BIT_SPACE 0x8
1891 #define BIT_UPPER 0x10
1892 #define BIT_MULTIBYTE 0x20
1894 /* Set a range START..END to WORK_AREA.
1895 The range is passed through TRANSLATE, so START and END
1896 should be untranslated. */
1897 #define SET_RANGE_TABLE_WORK_AREA(work_area, start, end) \
1898 do { \
1899 int tem; \
1900 tem = set_image_of_range (&work_area, start, end, translate); \
1901 if (tem > 0) \
1902 FREE_STACK_RETURN (tem); \
1903 } while (0)
1905 /* Free allocated memory for WORK_AREA. */
1906 #define FREE_RANGE_TABLE_WORK_AREA(work_area) \
1907 do { \
1908 if ((work_area).table) \
1909 free ((work_area).table); \
1910 } while (0)
1912 #define CLEAR_RANGE_TABLE_WORK_USED(work_area) ((work_area).used = 0, (work_area).bits = 0)
1913 #define RANGE_TABLE_WORK_USED(work_area) ((work_area).used)
1914 #define RANGE_TABLE_WORK_BITS(work_area) ((work_area).bits)
1915 #define RANGE_TABLE_WORK_ELT(work_area, i) ((work_area).table[i])
1918 /* Set the bit for character C in a list. */
1919 #define SET_LIST_BIT(c) (b[((c)) / BYTEWIDTH] |= 1 << ((c) % BYTEWIDTH))
1922 /* Get the next unsigned number in the uncompiled pattern. */
1923 #define GET_UNSIGNED_NUMBER(num) \
1924 do { if (p != pend) \
1926 PATFETCH (c); \
1927 if (c == ' ') \
1928 FREE_STACK_RETURN (REG_BADBR); \
1929 while ('0' <= c && c <= '9') \
1931 int prev; \
1932 if (num < 0) \
1933 num = 0; \
1934 prev = num; \
1935 num = num * 10 + c - '0'; \
1936 if (num / 10 != prev) \
1937 FREE_STACK_RETURN (REG_BADBR); \
1938 if (p == pend) \
1939 break; \
1940 PATFETCH (c); \
1942 if (c == ' ') \
1943 FREE_STACK_RETURN (REG_BADBR); \
1945 } while (0)
1947 #if WIDE_CHAR_SUPPORT
1948 /* The GNU C library provides support for user-defined character classes
1949 and the functions from ISO C amendement 1. */
1950 # ifdef CHARCLASS_NAME_MAX
1951 # define CHAR_CLASS_MAX_LENGTH CHARCLASS_NAME_MAX
1952 # else
1953 /* This shouldn't happen but some implementation might still have this
1954 problem. Use a reasonable default value. */
1955 # define CHAR_CLASS_MAX_LENGTH 256
1956 # endif
1957 typedef wctype_t re_wctype_t;
1958 typedef wchar_t re_wchar_t;
1959 # define re_wctype wctype
1960 # define re_iswctype iswctype
1961 # define re_wctype_to_bit(cc) 0
1962 #else
1963 # define CHAR_CLASS_MAX_LENGTH 9 /* Namely, `multibyte'. */
1964 # define btowc(c) c
1966 /* Character classes. */
1967 typedef enum { RECC_ERROR = 0,
1968 RECC_ALNUM, RECC_ALPHA, RECC_WORD,
1969 RECC_GRAPH, RECC_PRINT,
1970 RECC_LOWER, RECC_UPPER,
1971 RECC_PUNCT, RECC_CNTRL,
1972 RECC_DIGIT, RECC_XDIGIT,
1973 RECC_BLANK, RECC_SPACE,
1974 RECC_MULTIBYTE, RECC_NONASCII,
1975 RECC_ASCII, RECC_UNIBYTE
1976 } re_wctype_t;
1978 typedef int re_wchar_t;
1980 /* Map a string to the char class it names (if any). */
1981 static re_wctype_t
1982 re_wctype (str)
1983 re_char *str;
1985 const char *string = str;
1986 if (STREQ (string, "alnum")) return RECC_ALNUM;
1987 else if (STREQ (string, "alpha")) return RECC_ALPHA;
1988 else if (STREQ (string, "word")) return RECC_WORD;
1989 else if (STREQ (string, "ascii")) return RECC_ASCII;
1990 else if (STREQ (string, "nonascii")) return RECC_NONASCII;
1991 else if (STREQ (string, "graph")) return RECC_GRAPH;
1992 else if (STREQ (string, "lower")) return RECC_LOWER;
1993 else if (STREQ (string, "print")) return RECC_PRINT;
1994 else if (STREQ (string, "punct")) return RECC_PUNCT;
1995 else if (STREQ (string, "space")) return RECC_SPACE;
1996 else if (STREQ (string, "upper")) return RECC_UPPER;
1997 else if (STREQ (string, "unibyte")) return RECC_UNIBYTE;
1998 else if (STREQ (string, "multibyte")) return RECC_MULTIBYTE;
1999 else if (STREQ (string, "digit")) return RECC_DIGIT;
2000 else if (STREQ (string, "xdigit")) return RECC_XDIGIT;
2001 else if (STREQ (string, "cntrl")) return RECC_CNTRL;
2002 else if (STREQ (string, "blank")) return RECC_BLANK;
2003 else return 0;
2006 /* True iff CH is in the char class CC. */
2007 static boolean
2008 re_iswctype (ch, cc)
2009 int ch;
2010 re_wctype_t cc;
2012 switch (cc)
2014 case RECC_ALNUM: return ISALNUM (ch);
2015 case RECC_ALPHA: return ISALPHA (ch);
2016 case RECC_BLANK: return ISBLANK (ch);
2017 case RECC_CNTRL: return ISCNTRL (ch);
2018 case RECC_DIGIT: return ISDIGIT (ch);
2019 case RECC_GRAPH: return ISGRAPH (ch);
2020 case RECC_LOWER: return ISLOWER (ch);
2021 case RECC_PRINT: return ISPRINT (ch);
2022 case RECC_PUNCT: return ISPUNCT (ch);
2023 case RECC_SPACE: return ISSPACE (ch);
2024 case RECC_UPPER: return ISUPPER (ch);
2025 case RECC_XDIGIT: return ISXDIGIT (ch);
2026 case RECC_ASCII: return IS_REAL_ASCII (ch);
2027 case RECC_NONASCII: return !IS_REAL_ASCII (ch);
2028 case RECC_UNIBYTE: return ISUNIBYTE (ch);
2029 case RECC_MULTIBYTE: return !ISUNIBYTE (ch);
2030 case RECC_WORD: return ISWORD (ch);
2031 case RECC_ERROR: return false;
2032 default:
2033 abort();
2037 /* Return a bit-pattern to use in the range-table bits to match multibyte
2038 chars of class CC. */
2039 static int
2040 re_wctype_to_bit (cc)
2041 re_wctype_t cc;
2043 switch (cc)
2045 case RECC_NONASCII: case RECC_PRINT: case RECC_GRAPH:
2046 case RECC_MULTIBYTE: return BIT_MULTIBYTE;
2047 case RECC_ALPHA: case RECC_ALNUM: case RECC_WORD: return BIT_WORD;
2048 case RECC_LOWER: return BIT_LOWER;
2049 case RECC_UPPER: return BIT_UPPER;
2050 case RECC_PUNCT: return BIT_PUNCT;
2051 case RECC_SPACE: return BIT_SPACE;
2052 case RECC_ASCII: case RECC_DIGIT: case RECC_XDIGIT: case RECC_CNTRL:
2053 case RECC_BLANK: case RECC_UNIBYTE: case RECC_ERROR: return 0;
2054 default:
2055 abort();
2058 #endif
2060 /* Filling in the work area of a range. */
2062 /* Actually extend the space in WORK_AREA. */
2064 static void
2065 extend_range_table_work_area (work_area)
2066 struct range_table_work_area *work_area;
2068 work_area->allocated += 16 * sizeof (int);
2069 if (work_area->table)
2070 work_area->table
2071 = (int *) realloc (work_area->table, work_area->allocated);
2072 else
2073 work_area->table
2074 = (int *) malloc (work_area->allocated);
2077 #ifdef emacs
2079 /* Carefully find the ranges of codes that are equivalent
2080 under case conversion to the range start..end when passed through
2081 TRANSLATE. Handle the case where non-letters can come in between
2082 two upper-case letters (which happens in Latin-1).
2083 Also handle the case of groups of more than 2 case-equivalent chars.
2085 The basic method is to look at consecutive characters and see
2086 if they can form a run that can be handled as one.
2088 Returns -1 if successful, REG_ESPACE if ran out of space. */
2090 static int
2091 set_image_of_range_1 (work_area, start, end, translate)
2092 RE_TRANSLATE_TYPE translate;
2093 struct range_table_work_area *work_area;
2094 re_wchar_t start, end;
2096 /* `one_case' indicates a character, or a run of characters,
2097 each of which is an isolate (no case-equivalents).
2098 This includes all ASCII non-letters.
2100 `two_case' indicates a character, or a run of characters,
2101 each of which has two case-equivalent forms.
2102 This includes all ASCII letters.
2104 `strange' indicates a character that has more than one
2105 case-equivalent. */
2107 enum case_type {one_case, two_case, strange};
2109 /* Describe the run that is in progress,
2110 which the next character can try to extend.
2111 If run_type is strange, that means there really is no run.
2112 If run_type is one_case, then run_start...run_end is the run.
2113 If run_type is two_case, then the run is run_start...run_end,
2114 and the case-equivalents end at run_eqv_end. */
2116 enum case_type run_type = strange;
2117 int run_start, run_end, run_eqv_end;
2119 Lisp_Object eqv_table;
2121 if (!RE_TRANSLATE_P (translate))
2123 EXTEND_RANGE_TABLE (work_area, 2);
2124 work_area->table[work_area->used++] = (start);
2125 work_area->table[work_area->used++] = (end);
2126 return -1;
2129 eqv_table = XCHAR_TABLE (translate)->extras[2];
2131 for (; start <= end; start++)
2133 enum case_type this_type;
2134 int eqv = RE_TRANSLATE (eqv_table, start);
2135 int minchar, maxchar;
2137 /* Classify this character */
2138 if (eqv == start)
2139 this_type = one_case;
2140 else if (RE_TRANSLATE (eqv_table, eqv) == start)
2141 this_type = two_case;
2142 else
2143 this_type = strange;
2145 if (start < eqv)
2146 minchar = start, maxchar = eqv;
2147 else
2148 minchar = eqv, maxchar = start;
2150 /* Can this character extend the run in progress? */
2151 if (this_type == strange || this_type != run_type
2152 || !(minchar == run_end + 1
2153 && (run_type == two_case
2154 ? maxchar == run_eqv_end + 1 : 1)))
2156 /* No, end the run.
2157 Record each of its equivalent ranges. */
2158 if (run_type == one_case)
2160 EXTEND_RANGE_TABLE (work_area, 2);
2161 work_area->table[work_area->used++] = run_start;
2162 work_area->table[work_area->used++] = run_end;
2164 else if (run_type == two_case)
2166 EXTEND_RANGE_TABLE (work_area, 4);
2167 work_area->table[work_area->used++] = run_start;
2168 work_area->table[work_area->used++] = run_end;
2169 work_area->table[work_area->used++]
2170 = RE_TRANSLATE (eqv_table, run_start);
2171 work_area->table[work_area->used++]
2172 = RE_TRANSLATE (eqv_table, run_end);
2174 run_type = strange;
2177 if (this_type == strange)
2179 /* For a strange character, add each of its equivalents, one
2180 by one. Don't start a range. */
2183 EXTEND_RANGE_TABLE (work_area, 2);
2184 work_area->table[work_area->used++] = eqv;
2185 work_area->table[work_area->used++] = eqv;
2186 eqv = RE_TRANSLATE (eqv_table, eqv);
2188 while (eqv != start);
2191 /* Add this char to the run, or start a new run. */
2192 else if (run_type == strange)
2194 /* Initialize a new range. */
2195 run_type = this_type;
2196 run_start = start;
2197 run_end = start;
2198 run_eqv_end = RE_TRANSLATE (eqv_table, run_end);
2200 else
2202 /* Extend a running range. */
2203 run_end = minchar;
2204 run_eqv_end = RE_TRANSLATE (eqv_table, run_end);
2208 /* If a run is still in progress at the end, finish it now
2209 by recording its equivalent ranges. */
2210 if (run_type == one_case)
2212 EXTEND_RANGE_TABLE (work_area, 2);
2213 work_area->table[work_area->used++] = run_start;
2214 work_area->table[work_area->used++] = run_end;
2216 else if (run_type == two_case)
2218 EXTEND_RANGE_TABLE (work_area, 4);
2219 work_area->table[work_area->used++] = run_start;
2220 work_area->table[work_area->used++] = run_end;
2221 work_area->table[work_area->used++]
2222 = RE_TRANSLATE (eqv_table, run_start);
2223 work_area->table[work_area->used++]
2224 = RE_TRANSLATE (eqv_table, run_end);
2227 return -1;
2230 #endif /* emacs */
2232 /* Record the the image of the range start..end when passed through
2233 TRANSLATE. This is not necessarily TRANSLATE(start)..TRANSLATE(end)
2234 and is not even necessarily contiguous.
2235 Normally we approximate it with the smallest contiguous range that contains
2236 all the chars we need. However, for Latin-1 we go to extra effort
2237 to do a better job.
2239 This function is not called for ASCII ranges.
2241 Returns -1 if successful, REG_ESPACE if ran out of space. */
2243 static int
2244 set_image_of_range (work_area, start, end, translate)
2245 RE_TRANSLATE_TYPE translate;
2246 struct range_table_work_area *work_area;
2247 re_wchar_t start, end;
2249 re_wchar_t cmin, cmax;
2251 #ifdef emacs
2252 /* For Latin-1 ranges, use set_image_of_range_1
2253 to get proper handling of ranges that include letters and nonletters.
2254 For a range that includes the whole of Latin-1, this is not necessary.
2255 For other character sets, we don't bother to get this right. */
2256 if (RE_TRANSLATE_P (translate) && start < 04400
2257 && !(start < 04200 && end >= 04377))
2259 int newend;
2260 int tem;
2261 newend = end;
2262 if (newend > 04377)
2263 newend = 04377;
2264 tem = set_image_of_range_1 (work_area, start, newend, translate);
2265 if (tem > 0)
2266 return tem;
2268 start = 04400;
2269 if (end < 04400)
2270 return -1;
2272 #endif
2274 EXTEND_RANGE_TABLE (work_area, 2);
2275 work_area->table[work_area->used++] = (start);
2276 work_area->table[work_area->used++] = (end);
2278 cmin = -1, cmax = -1;
2280 if (RE_TRANSLATE_P (translate))
2282 int ch;
2284 for (ch = start; ch <= end; ch++)
2286 re_wchar_t c = TRANSLATE (ch);
2287 if (! (start <= c && c <= end))
2289 if (cmin == -1)
2290 cmin = c, cmax = c;
2291 else
2293 cmin = MIN (cmin, c);
2294 cmax = MAX (cmax, c);
2299 if (cmin != -1)
2301 EXTEND_RANGE_TABLE (work_area, 2);
2302 work_area->table[work_area->used++] = (cmin);
2303 work_area->table[work_area->used++] = (cmax);
2307 return -1;
2310 #ifndef MATCH_MAY_ALLOCATE
2312 /* If we cannot allocate large objects within re_match_2_internal,
2313 we make the fail stack and register vectors global.
2314 The fail stack, we grow to the maximum size when a regexp
2315 is compiled.
2316 The register vectors, we adjust in size each time we
2317 compile a regexp, according to the number of registers it needs. */
2319 static fail_stack_type fail_stack;
2321 /* Size with which the following vectors are currently allocated.
2322 That is so we can make them bigger as needed,
2323 but never make them smaller. */
2324 static int regs_allocated_size;
2326 static re_char ** regstart, ** regend;
2327 static re_char **best_regstart, **best_regend;
2329 /* Make the register vectors big enough for NUM_REGS registers,
2330 but don't make them smaller. */
2332 static
2333 regex_grow_registers (num_regs)
2334 int num_regs;
2336 if (num_regs > regs_allocated_size)
2338 RETALLOC_IF (regstart, num_regs, re_char *);
2339 RETALLOC_IF (regend, num_regs, re_char *);
2340 RETALLOC_IF (best_regstart, num_regs, re_char *);
2341 RETALLOC_IF (best_regend, num_regs, re_char *);
2343 regs_allocated_size = num_regs;
2347 #endif /* not MATCH_MAY_ALLOCATE */
2349 static boolean group_in_compile_stack _RE_ARGS ((compile_stack_type
2350 compile_stack,
2351 regnum_t regnum));
2353 /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
2354 Returns one of error codes defined in `regex.h', or zero for success.
2356 Assumes the `allocated' (and perhaps `buffer') and `translate'
2357 fields are set in BUFP on entry.
2359 If it succeeds, results are put in BUFP (if it returns an error, the
2360 contents of BUFP are undefined):
2361 `buffer' is the compiled pattern;
2362 `syntax' is set to SYNTAX;
2363 `used' is set to the length of the compiled pattern;
2364 `fastmap_accurate' is zero;
2365 `re_nsub' is the number of subexpressions in PATTERN;
2366 `not_bol' and `not_eol' are zero;
2368 The `fastmap' field is neither examined nor set. */
2370 /* Insert the `jump' from the end of last alternative to "here".
2371 The space for the jump has already been allocated. */
2372 #define FIXUP_ALT_JUMP() \
2373 do { \
2374 if (fixup_alt_jump) \
2375 STORE_JUMP (jump, fixup_alt_jump, b); \
2376 } while (0)
2379 /* Return, freeing storage we allocated. */
2380 #define FREE_STACK_RETURN(value) \
2381 do { \
2382 FREE_RANGE_TABLE_WORK_AREA (range_table_work); \
2383 free (compile_stack.stack); \
2384 return value; \
2385 } while (0)
2387 static reg_errcode_t
2388 regex_compile (pattern, size, syntax, bufp)
2389 re_char *pattern;
2390 size_t size;
2391 reg_syntax_t syntax;
2392 struct re_pattern_buffer *bufp;
2394 /* We fetch characters from PATTERN here. */
2395 register re_wchar_t c, c1;
2397 /* A random temporary spot in PATTERN. */
2398 re_char *p1;
2400 /* Points to the end of the buffer, where we should append. */
2401 register unsigned char *b;
2403 /* Keeps track of unclosed groups. */
2404 compile_stack_type compile_stack;
2406 /* Points to the current (ending) position in the pattern. */
2407 #ifdef AIX
2408 /* `const' makes AIX compiler fail. */
2409 unsigned char *p = pattern;
2410 #else
2411 re_char *p = pattern;
2412 #endif
2413 re_char *pend = pattern + size;
2415 /* How to translate the characters in the pattern. */
2416 RE_TRANSLATE_TYPE translate = bufp->translate;
2418 /* Address of the count-byte of the most recently inserted `exactn'
2419 command. This makes it possible to tell if a new exact-match
2420 character can be added to that command or if the character requires
2421 a new `exactn' command. */
2422 unsigned char *pending_exact = 0;
2424 /* Address of start of the most recently finished expression.
2425 This tells, e.g., postfix * where to find the start of its
2426 operand. Reset at the beginning of groups and alternatives. */
2427 unsigned char *laststart = 0;
2429 /* Address of beginning of regexp, or inside of last group. */
2430 unsigned char *begalt;
2432 /* Place in the uncompiled pattern (i.e., the {) to
2433 which to go back if the interval is invalid. */
2434 re_char *beg_interval;
2436 /* Address of the place where a forward jump should go to the end of
2437 the containing expression. Each alternative of an `or' -- except the
2438 last -- ends with a forward jump of this sort. */
2439 unsigned char *fixup_alt_jump = 0;
2441 /* Counts open-groups as they are encountered. Remembered for the
2442 matching close-group on the compile stack, so the same register
2443 number is put in the stop_memory as the start_memory. */
2444 regnum_t regnum = 0;
2446 /* Work area for range table of charset. */
2447 struct range_table_work_area range_table_work;
2449 /* If the object matched can contain multibyte characters. */
2450 const boolean multibyte = RE_MULTIBYTE_P (bufp);
2452 #ifdef DEBUG
2453 debug++;
2454 DEBUG_PRINT1 ("\nCompiling pattern: ");
2455 if (debug > 0)
2457 unsigned debug_count;
2459 for (debug_count = 0; debug_count < size; debug_count++)
2460 putchar (pattern[debug_count]);
2461 putchar ('\n');
2463 #endif /* DEBUG */
2465 /* Initialize the compile stack. */
2466 compile_stack.stack = TALLOC (INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
2467 if (compile_stack.stack == NULL)
2468 return REG_ESPACE;
2470 compile_stack.size = INIT_COMPILE_STACK_SIZE;
2471 compile_stack.avail = 0;
2473 range_table_work.table = 0;
2474 range_table_work.allocated = 0;
2476 /* Initialize the pattern buffer. */
2477 bufp->syntax = syntax;
2478 bufp->fastmap_accurate = 0;
2479 bufp->not_bol = bufp->not_eol = 0;
2481 /* Set `used' to zero, so that if we return an error, the pattern
2482 printer (for debugging) will think there's no pattern. We reset it
2483 at the end. */
2484 bufp->used = 0;
2486 /* Always count groups, whether or not bufp->no_sub is set. */
2487 bufp->re_nsub = 0;
2489 #if !defined emacs && !defined SYNTAX_TABLE
2490 /* Initialize the syntax table. */
2491 init_syntax_once ();
2492 #endif
2494 if (bufp->allocated == 0)
2496 if (bufp->buffer)
2497 { /* If zero allocated, but buffer is non-null, try to realloc
2498 enough space. This loses if buffer's address is bogus, but
2499 that is the user's responsibility. */
2500 RETALLOC (bufp->buffer, INIT_BUF_SIZE, unsigned char);
2502 else
2503 { /* Caller did not allocate a buffer. Do it for them. */
2504 bufp->buffer = TALLOC (INIT_BUF_SIZE, unsigned char);
2506 if (!bufp->buffer) FREE_STACK_RETURN (REG_ESPACE);
2508 bufp->allocated = INIT_BUF_SIZE;
2511 begalt = b = bufp->buffer;
2513 /* Loop through the uncompiled pattern until we're at the end. */
2514 while (p != pend)
2516 PATFETCH (c);
2518 switch (c)
2520 case '^':
2522 if ( /* If at start of pattern, it's an operator. */
2523 p == pattern + 1
2524 /* If context independent, it's an operator. */
2525 || syntax & RE_CONTEXT_INDEP_ANCHORS
2526 /* Otherwise, depends on what's come before. */
2527 || at_begline_loc_p (pattern, p, syntax))
2528 BUF_PUSH ((syntax & RE_NO_NEWLINE_ANCHOR) ? begbuf : begline);
2529 else
2530 goto normal_char;
2532 break;
2535 case '$':
2537 if ( /* If at end of pattern, it's an operator. */
2538 p == pend
2539 /* If context independent, it's an operator. */
2540 || syntax & RE_CONTEXT_INDEP_ANCHORS
2541 /* Otherwise, depends on what's next. */
2542 || at_endline_loc_p (p, pend, syntax))
2543 BUF_PUSH ((syntax & RE_NO_NEWLINE_ANCHOR) ? endbuf : endline);
2544 else
2545 goto normal_char;
2547 break;
2550 case '+':
2551 case '?':
2552 if ((syntax & RE_BK_PLUS_QM)
2553 || (syntax & RE_LIMITED_OPS))
2554 goto normal_char;
2555 handle_plus:
2556 case '*':
2557 /* If there is no previous pattern... */
2558 if (!laststart)
2560 if (syntax & RE_CONTEXT_INVALID_OPS)
2561 FREE_STACK_RETURN (REG_BADRPT);
2562 else if (!(syntax & RE_CONTEXT_INDEP_OPS))
2563 goto normal_char;
2567 /* 1 means zero (many) matches is allowed. */
2568 boolean zero_times_ok = 0, many_times_ok = 0;
2569 boolean greedy = 1;
2571 /* If there is a sequence of repetition chars, collapse it
2572 down to just one (the right one). We can't combine
2573 interval operators with these because of, e.g., `a{2}*',
2574 which should only match an even number of `a's. */
2576 for (;;)
2578 if ((syntax & RE_FRUGAL)
2579 && c == '?' && (zero_times_ok || many_times_ok))
2580 greedy = 0;
2581 else
2583 zero_times_ok |= c != '+';
2584 many_times_ok |= c != '?';
2587 if (p == pend)
2588 break;
2589 else if (*p == '*'
2590 || (!(syntax & RE_BK_PLUS_QM)
2591 && (*p == '+' || *p == '?')))
2593 else if (syntax & RE_BK_PLUS_QM && *p == '\\')
2595 if (p+1 == pend)
2596 FREE_STACK_RETURN (REG_EESCAPE);
2597 if (p[1] == '+' || p[1] == '?')
2598 PATFETCH (c); /* Gobble up the backslash. */
2599 else
2600 break;
2602 else
2603 break;
2604 /* If we get here, we found another repeat character. */
2605 PATFETCH (c);
2608 /* Star, etc. applied to an empty pattern is equivalent
2609 to an empty pattern. */
2610 if (!laststart || laststart == b)
2611 break;
2613 /* Now we know whether or not zero matches is allowed
2614 and also whether or not two or more matches is allowed. */
2615 if (greedy)
2617 if (many_times_ok)
2619 boolean simple = skip_one_char (laststart) == b;
2620 unsigned int startoffset = 0;
2621 re_opcode_t ofj =
2622 /* Check if the loop can match the empty string. */
2623 (simple || !analyse_first (laststart, b, NULL, 0))
2624 ? on_failure_jump : on_failure_jump_loop;
2625 assert (skip_one_char (laststart) <= b);
2627 if (!zero_times_ok && simple)
2628 { /* Since simple * loops can be made faster by using
2629 on_failure_keep_string_jump, we turn simple P+
2630 into PP* if P is simple. */
2631 unsigned char *p1, *p2;
2632 startoffset = b - laststart;
2633 GET_BUFFER_SPACE (startoffset);
2634 p1 = b; p2 = laststart;
2635 while (p2 < p1)
2636 *b++ = *p2++;
2637 zero_times_ok = 1;
2640 GET_BUFFER_SPACE (6);
2641 if (!zero_times_ok)
2642 /* A + loop. */
2643 STORE_JUMP (ofj, b, b + 6);
2644 else
2645 /* Simple * loops can use on_failure_keep_string_jump
2646 depending on what follows. But since we don't know
2647 that yet, we leave the decision up to
2648 on_failure_jump_smart. */
2649 INSERT_JUMP (simple ? on_failure_jump_smart : ofj,
2650 laststart + startoffset, b + 6);
2651 b += 3;
2652 STORE_JUMP (jump, b, laststart + startoffset);
2653 b += 3;
2655 else
2657 /* A simple ? pattern. */
2658 assert (zero_times_ok);
2659 GET_BUFFER_SPACE (3);
2660 INSERT_JUMP (on_failure_jump, laststart, b + 3);
2661 b += 3;
2664 else /* not greedy */
2665 { /* I wish the greedy and non-greedy cases could be merged. */
2667 GET_BUFFER_SPACE (7); /* We might use less. */
2668 if (many_times_ok)
2670 boolean emptyp = analyse_first (laststart, b, NULL, 0);
2672 /* The non-greedy multiple match looks like
2673 a repeat..until: we only need a conditional jump
2674 at the end of the loop. */
2675 if (emptyp) BUF_PUSH (no_op);
2676 STORE_JUMP (emptyp ? on_failure_jump_nastyloop
2677 : on_failure_jump, b, laststart);
2678 b += 3;
2679 if (zero_times_ok)
2681 /* The repeat...until naturally matches one or more.
2682 To also match zero times, we need to first jump to
2683 the end of the loop (its conditional jump). */
2684 INSERT_JUMP (jump, laststart, b);
2685 b += 3;
2688 else
2690 /* non-greedy a?? */
2691 INSERT_JUMP (jump, laststart, b + 3);
2692 b += 3;
2693 INSERT_JUMP (on_failure_jump, laststart, laststart + 6);
2694 b += 3;
2698 pending_exact = 0;
2699 break;
2702 case '.':
2703 laststart = b;
2704 BUF_PUSH (anychar);
2705 break;
2708 case '[':
2710 CLEAR_RANGE_TABLE_WORK_USED (range_table_work);
2712 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2714 /* Ensure that we have enough space to push a charset: the
2715 opcode, the length count, and the bitset; 34 bytes in all. */
2716 GET_BUFFER_SPACE (34);
2718 laststart = b;
2720 /* We test `*p == '^' twice, instead of using an if
2721 statement, so we only need one BUF_PUSH. */
2722 BUF_PUSH (*p == '^' ? charset_not : charset);
2723 if (*p == '^')
2724 p++;
2726 /* Remember the first position in the bracket expression. */
2727 p1 = p;
2729 /* Push the number of bytes in the bitmap. */
2730 BUF_PUSH ((1 << BYTEWIDTH) / BYTEWIDTH);
2732 /* Clear the whole map. */
2733 bzero (b, (1 << BYTEWIDTH) / BYTEWIDTH);
2735 /* charset_not matches newline according to a syntax bit. */
2736 if ((re_opcode_t) b[-2] == charset_not
2737 && (syntax & RE_HAT_LISTS_NOT_NEWLINE))
2738 SET_LIST_BIT ('\n');
2740 /* Read in characters and ranges, setting map bits. */
2741 for (;;)
2743 boolean escaped_char = false;
2744 const unsigned char *p2 = p;
2746 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2748 /* Don't translate yet. The range TRANSLATE(X..Y) cannot
2749 always be determined from TRANSLATE(X) and TRANSLATE(Y)
2750 So the translation is done later in a loop. Example:
2751 (let ((case-fold-search t)) (string-match "[A-_]" "A")) */
2752 PATFETCH (c);
2754 /* \ might escape characters inside [...] and [^...]. */
2755 if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\')
2757 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2759 PATFETCH (c);
2760 escaped_char = true;
2762 else
2764 /* Could be the end of the bracket expression. If it's
2765 not (i.e., when the bracket expression is `[]' so
2766 far), the ']' character bit gets set way below. */
2767 if (c == ']' && p2 != p1)
2768 break;
2771 /* What should we do for the character which is
2772 greater than 0x7F, but not BASE_LEADING_CODE_P?
2773 XXX */
2775 /* See if we're at the beginning of a possible character
2776 class. */
2778 if (!escaped_char &&
2779 syntax & RE_CHAR_CLASSES && c == '[' && *p == ':')
2781 /* Leave room for the null. */
2782 unsigned char str[CHAR_CLASS_MAX_LENGTH + 1];
2783 const unsigned char *class_beg;
2785 PATFETCH (c);
2786 c1 = 0;
2787 class_beg = p;
2789 /* If pattern is `[[:'. */
2790 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2792 for (;;)
2794 PATFETCH (c);
2795 if ((c == ':' && *p == ']') || p == pend)
2796 break;
2797 if (c1 < CHAR_CLASS_MAX_LENGTH)
2798 str[c1++] = c;
2799 else
2800 /* This is in any case an invalid class name. */
2801 str[0] = '\0';
2803 str[c1] = '\0';
2805 /* If isn't a word bracketed by `[:' and `:]':
2806 undo the ending character, the letters, and
2807 leave the leading `:' and `[' (but set bits for
2808 them). */
2809 if (c == ':' && *p == ']')
2811 re_wchar_t ch;
2812 re_wctype_t cc;
2814 cc = re_wctype (str);
2816 if (cc == 0)
2817 FREE_STACK_RETURN (REG_ECTYPE);
2819 /* Throw away the ] at the end of the character
2820 class. */
2821 PATFETCH (c);
2823 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2825 /* Most character classes in a multibyte match
2826 just set a flag. Exceptions are is_blank,
2827 is_digit, is_cntrl, and is_xdigit, since
2828 they can only match ASCII characters. We
2829 don't need to handle them for multibyte.
2830 They are distinguished by a negative wctype. */
2832 if (multibyte)
2833 SET_RANGE_TABLE_WORK_AREA_BIT (range_table_work,
2834 re_wctype_to_bit (cc));
2836 for (ch = 0; ch < 1 << BYTEWIDTH; ++ch)
2838 int translated = TRANSLATE (ch);
2839 if (re_iswctype (btowc (ch), cc))
2840 SET_LIST_BIT (translated);
2843 /* Repeat the loop. */
2844 continue;
2846 else
2848 /* Go back to right after the "[:". */
2849 p = class_beg;
2850 SET_LIST_BIT ('[');
2852 /* Because the `:' may starts the range, we
2853 can't simply set bit and repeat the loop.
2854 Instead, just set it to C and handle below. */
2855 c = ':';
2859 if (p < pend && p[0] == '-' && p[1] != ']')
2862 /* Discard the `-'. */
2863 PATFETCH (c1);
2865 /* Fetch the character which ends the range. */
2866 PATFETCH (c1);
2868 if (SINGLE_BYTE_CHAR_P (c))
2870 if (! SINGLE_BYTE_CHAR_P (c1))
2872 /* Handle a range starting with a
2873 character of less than 256, and ending
2874 with a character of not less than 256.
2875 Split that into two ranges, the low one
2876 ending at 0377, and the high one
2877 starting at the smallest character in
2878 the charset of C1 and ending at C1. */
2879 int charset = CHAR_CHARSET (c1);
2880 re_wchar_t c2 = MAKE_CHAR (charset, 0, 0);
2882 SET_RANGE_TABLE_WORK_AREA (range_table_work,
2883 c2, c1);
2884 c1 = 0377;
2887 else if (!SAME_CHARSET_P (c, c1))
2888 FREE_STACK_RETURN (REG_ERANGE);
2890 else
2891 /* Range from C to C. */
2892 c1 = c;
2894 /* Set the range ... */
2895 if (SINGLE_BYTE_CHAR_P (c))
2896 /* ... into bitmap. */
2898 re_wchar_t this_char;
2899 re_wchar_t range_start = c, range_end = c1;
2901 /* If the start is after the end, the range is empty. */
2902 if (range_start > range_end)
2904 if (syntax & RE_NO_EMPTY_RANGES)
2905 FREE_STACK_RETURN (REG_ERANGE);
2906 /* Else, repeat the loop. */
2908 else
2910 for (this_char = range_start; this_char <= range_end;
2911 this_char++)
2912 SET_LIST_BIT (TRANSLATE (this_char));
2915 else
2916 /* ... into range table. */
2917 SET_RANGE_TABLE_WORK_AREA (range_table_work, c, c1);
2920 /* Discard any (non)matching list bytes that are all 0 at the
2921 end of the map. Decrease the map-length byte too. */
2922 while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
2923 b[-1]--;
2924 b += b[-1];
2926 /* Build real range table from work area. */
2927 if (RANGE_TABLE_WORK_USED (range_table_work)
2928 || RANGE_TABLE_WORK_BITS (range_table_work))
2930 int i;
2931 int used = RANGE_TABLE_WORK_USED (range_table_work);
2933 /* Allocate space for COUNT + RANGE_TABLE. Needs two
2934 bytes for flags, two for COUNT, and three bytes for
2935 each character. */
2936 GET_BUFFER_SPACE (4 + used * 3);
2938 /* Indicate the existence of range table. */
2939 laststart[1] |= 0x80;
2941 /* Store the character class flag bits into the range table.
2942 If not in emacs, these flag bits are always 0. */
2943 *b++ = RANGE_TABLE_WORK_BITS (range_table_work) & 0xff;
2944 *b++ = RANGE_TABLE_WORK_BITS (range_table_work) >> 8;
2946 STORE_NUMBER_AND_INCR (b, used / 2);
2947 for (i = 0; i < used; i++)
2948 STORE_CHARACTER_AND_INCR
2949 (b, RANGE_TABLE_WORK_ELT (range_table_work, i));
2952 break;
2955 case '(':
2956 if (syntax & RE_NO_BK_PARENS)
2957 goto handle_open;
2958 else
2959 goto normal_char;
2962 case ')':
2963 if (syntax & RE_NO_BK_PARENS)
2964 goto handle_close;
2965 else
2966 goto normal_char;
2969 case '\n':
2970 if (syntax & RE_NEWLINE_ALT)
2971 goto handle_alt;
2972 else
2973 goto normal_char;
2976 case '|':
2977 if (syntax & RE_NO_BK_VBAR)
2978 goto handle_alt;
2979 else
2980 goto normal_char;
2983 case '{':
2984 if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
2985 goto handle_interval;
2986 else
2987 goto normal_char;
2990 case '\\':
2991 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2993 /* Do not translate the character after the \, so that we can
2994 distinguish, e.g., \B from \b, even if we normally would
2995 translate, e.g., B to b. */
2996 PATFETCH (c);
2998 switch (c)
3000 case '(':
3001 if (syntax & RE_NO_BK_PARENS)
3002 goto normal_backslash;
3004 handle_open:
3006 int shy = 0;
3007 if (p+1 < pend)
3009 /* Look for a special (?...) construct */
3010 if ((syntax & RE_SHY_GROUPS) && *p == '?')
3012 PATFETCH (c); /* Gobble up the '?'. */
3013 PATFETCH (c);
3014 switch (c)
3016 case ':': shy = 1; break;
3017 default:
3018 /* Only (?:...) is supported right now. */
3019 FREE_STACK_RETURN (REG_BADPAT);
3024 if (!shy)
3026 bufp->re_nsub++;
3027 regnum++;
3030 if (COMPILE_STACK_FULL)
3032 RETALLOC (compile_stack.stack, compile_stack.size << 1,
3033 compile_stack_elt_t);
3034 if (compile_stack.stack == NULL) return REG_ESPACE;
3036 compile_stack.size <<= 1;
3039 /* These are the values to restore when we hit end of this
3040 group. They are all relative offsets, so that if the
3041 whole pattern moves because of realloc, they will still
3042 be valid. */
3043 COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
3044 COMPILE_STACK_TOP.fixup_alt_jump
3045 = fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
3046 COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
3047 COMPILE_STACK_TOP.regnum = shy ? -regnum : regnum;
3049 /* Do not push a
3050 start_memory for groups beyond the last one we can
3051 represent in the compiled pattern. */
3052 if (regnum <= MAX_REGNUM && !shy)
3053 BUF_PUSH_2 (start_memory, regnum);
3055 compile_stack.avail++;
3057 fixup_alt_jump = 0;
3058 laststart = 0;
3059 begalt = b;
3060 /* If we've reached MAX_REGNUM groups, then this open
3061 won't actually generate any code, so we'll have to
3062 clear pending_exact explicitly. */
3063 pending_exact = 0;
3064 break;
3067 case ')':
3068 if (syntax & RE_NO_BK_PARENS) goto normal_backslash;
3070 if (COMPILE_STACK_EMPTY)
3072 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
3073 goto normal_backslash;
3074 else
3075 FREE_STACK_RETURN (REG_ERPAREN);
3078 handle_close:
3079 FIXUP_ALT_JUMP ();
3081 /* See similar code for backslashed left paren above. */
3082 if (COMPILE_STACK_EMPTY)
3084 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
3085 goto normal_char;
3086 else
3087 FREE_STACK_RETURN (REG_ERPAREN);
3090 /* Since we just checked for an empty stack above, this
3091 ``can't happen''. */
3092 assert (compile_stack.avail != 0);
3094 /* We don't just want to restore into `regnum', because
3095 later groups should continue to be numbered higher,
3096 as in `(ab)c(de)' -- the second group is #2. */
3097 regnum_t this_group_regnum;
3099 compile_stack.avail--;
3100 begalt = bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
3101 fixup_alt_jump
3102 = COMPILE_STACK_TOP.fixup_alt_jump
3103 ? bufp->buffer + COMPILE_STACK_TOP.fixup_alt_jump - 1
3104 : 0;
3105 laststart = bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
3106 this_group_regnum = COMPILE_STACK_TOP.regnum;
3107 /* If we've reached MAX_REGNUM groups, then this open
3108 won't actually generate any code, so we'll have to
3109 clear pending_exact explicitly. */
3110 pending_exact = 0;
3112 /* We're at the end of the group, so now we know how many
3113 groups were inside this one. */
3114 if (this_group_regnum <= MAX_REGNUM && this_group_regnum > 0)
3115 BUF_PUSH_2 (stop_memory, this_group_regnum);
3117 break;
3120 case '|': /* `\|'. */
3121 if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
3122 goto normal_backslash;
3123 handle_alt:
3124 if (syntax & RE_LIMITED_OPS)
3125 goto normal_char;
3127 /* Insert before the previous alternative a jump which
3128 jumps to this alternative if the former fails. */
3129 GET_BUFFER_SPACE (3);
3130 INSERT_JUMP (on_failure_jump, begalt, b + 6);
3131 pending_exact = 0;
3132 b += 3;
3134 /* The alternative before this one has a jump after it
3135 which gets executed if it gets matched. Adjust that
3136 jump so it will jump to this alternative's analogous
3137 jump (put in below, which in turn will jump to the next
3138 (if any) alternative's such jump, etc.). The last such
3139 jump jumps to the correct final destination. A picture:
3140 _____ _____
3141 | | | |
3142 | v | v
3143 a | b | c
3145 If we are at `b', then fixup_alt_jump right now points to a
3146 three-byte space after `a'. We'll put in the jump, set
3147 fixup_alt_jump to right after `b', and leave behind three
3148 bytes which we'll fill in when we get to after `c'. */
3150 FIXUP_ALT_JUMP ();
3152 /* Mark and leave space for a jump after this alternative,
3153 to be filled in later either by next alternative or
3154 when know we're at the end of a series of alternatives. */
3155 fixup_alt_jump = b;
3156 GET_BUFFER_SPACE (3);
3157 b += 3;
3159 laststart = 0;
3160 begalt = b;
3161 break;
3164 case '{':
3165 /* If \{ is a literal. */
3166 if (!(syntax & RE_INTERVALS)
3167 /* If we're at `\{' and it's not the open-interval
3168 operator. */
3169 || (syntax & RE_NO_BK_BRACES))
3170 goto normal_backslash;
3172 handle_interval:
3174 /* If got here, then the syntax allows intervals. */
3176 /* At least (most) this many matches must be made. */
3177 int lower_bound = 0, upper_bound = -1;
3179 beg_interval = p;
3181 if (p == pend)
3182 FREE_STACK_RETURN (REG_EBRACE);
3184 GET_UNSIGNED_NUMBER (lower_bound);
3186 if (c == ',')
3187 GET_UNSIGNED_NUMBER (upper_bound);
3188 else
3189 /* Interval such as `{1}' => match exactly once. */
3190 upper_bound = lower_bound;
3192 if (lower_bound < 0 || upper_bound > RE_DUP_MAX
3193 || (upper_bound >= 0 && lower_bound > upper_bound))
3194 FREE_STACK_RETURN (REG_BADBR);
3196 if (!(syntax & RE_NO_BK_BRACES))
3198 if (c != '\\')
3199 FREE_STACK_RETURN (REG_BADBR);
3201 PATFETCH (c);
3204 if (c != '}')
3205 FREE_STACK_RETURN (REG_BADBR);
3207 /* We just parsed a valid interval. */
3209 /* If it's invalid to have no preceding re. */
3210 if (!laststart)
3212 if (syntax & RE_CONTEXT_INVALID_OPS)
3213 FREE_STACK_RETURN (REG_BADRPT);
3214 else if (syntax & RE_CONTEXT_INDEP_OPS)
3215 laststart = b;
3216 else
3217 goto unfetch_interval;
3220 if (upper_bound == 0)
3221 /* If the upper bound is zero, just drop the sub pattern
3222 altogether. */
3223 b = laststart;
3224 else if (lower_bound == 1 && upper_bound == 1)
3225 /* Just match it once: nothing to do here. */
3228 /* Otherwise, we have a nontrivial interval. When
3229 we're all done, the pattern will look like:
3230 set_number_at <jump count> <upper bound>
3231 set_number_at <succeed_n count> <lower bound>
3232 succeed_n <after jump addr> <succeed_n count>
3233 <body of loop>
3234 jump_n <succeed_n addr> <jump count>
3235 (The upper bound and `jump_n' are omitted if
3236 `upper_bound' is 1, though.) */
3237 else
3238 { /* If the upper bound is > 1, we need to insert
3239 more at the end of the loop. */
3240 unsigned int nbytes = (upper_bound < 0 ? 3
3241 : upper_bound > 1 ? 5 : 0);
3242 unsigned int startoffset = 0;
3244 GET_BUFFER_SPACE (20); /* We might use less. */
3246 if (lower_bound == 0)
3248 /* A succeed_n that starts with 0 is really a
3249 a simple on_failure_jump_loop. */
3250 INSERT_JUMP (on_failure_jump_loop, laststart,
3251 b + 3 + nbytes);
3252 b += 3;
3254 else
3256 /* Initialize lower bound of the `succeed_n', even
3257 though it will be set during matching by its
3258 attendant `set_number_at' (inserted next),
3259 because `re_compile_fastmap' needs to know.
3260 Jump to the `jump_n' we might insert below. */
3261 INSERT_JUMP2 (succeed_n, laststart,
3262 b + 5 + nbytes,
3263 lower_bound);
3264 b += 5;
3266 /* Code to initialize the lower bound. Insert
3267 before the `succeed_n'. The `5' is the last two
3268 bytes of this `set_number_at', plus 3 bytes of
3269 the following `succeed_n'. */
3270 insert_op2 (set_number_at, laststart, 5, lower_bound, b);
3271 b += 5;
3272 startoffset += 5;
3275 if (upper_bound < 0)
3277 /* A negative upper bound stands for infinity,
3278 in which case it degenerates to a plain jump. */
3279 STORE_JUMP (jump, b, laststart + startoffset);
3280 b += 3;
3282 else if (upper_bound > 1)
3283 { /* More than one repetition is allowed, so
3284 append a backward jump to the `succeed_n'
3285 that starts this interval.
3287 When we've reached this during matching,
3288 we'll have matched the interval once, so
3289 jump back only `upper_bound - 1' times. */
3290 STORE_JUMP2 (jump_n, b, laststart + startoffset,
3291 upper_bound - 1);
3292 b += 5;
3294 /* The location we want to set is the second
3295 parameter of the `jump_n'; that is `b-2' as
3296 an absolute address. `laststart' will be
3297 the `set_number_at' we're about to insert;
3298 `laststart+3' the number to set, the source
3299 for the relative address. But we are
3300 inserting into the middle of the pattern --
3301 so everything is getting moved up by 5.
3302 Conclusion: (b - 2) - (laststart + 3) + 5,
3303 i.e., b - laststart.
3305 We insert this at the beginning of the loop
3306 so that if we fail during matching, we'll
3307 reinitialize the bounds. */
3308 insert_op2 (set_number_at, laststart, b - laststart,
3309 upper_bound - 1, b);
3310 b += 5;
3313 pending_exact = 0;
3314 beg_interval = NULL;
3316 break;
3318 unfetch_interval:
3319 /* If an invalid interval, match the characters as literals. */
3320 assert (beg_interval);
3321 p = beg_interval;
3322 beg_interval = NULL;
3324 /* normal_char and normal_backslash need `c'. */
3325 c = '{';
3327 if (!(syntax & RE_NO_BK_BRACES))
3329 assert (p > pattern && p[-1] == '\\');
3330 goto normal_backslash;
3332 else
3333 goto normal_char;
3335 #ifdef emacs
3336 /* There is no way to specify the before_dot and after_dot
3337 operators. rms says this is ok. --karl */
3338 case '=':
3339 BUF_PUSH (at_dot);
3340 break;
3342 case 's':
3343 laststart = b;
3344 PATFETCH (c);
3345 BUF_PUSH_2 (syntaxspec, syntax_spec_code[c]);
3346 break;
3348 case 'S':
3349 laststart = b;
3350 PATFETCH (c);
3351 BUF_PUSH_2 (notsyntaxspec, syntax_spec_code[c]);
3352 break;
3354 case 'c':
3355 laststart = b;
3356 PATFETCH (c);
3357 BUF_PUSH_2 (categoryspec, c);
3358 break;
3360 case 'C':
3361 laststart = b;
3362 PATFETCH (c);
3363 BUF_PUSH_2 (notcategoryspec, c);
3364 break;
3365 #endif /* emacs */
3368 case 'w':
3369 if (syntax & RE_NO_GNU_OPS)
3370 goto normal_char;
3371 laststart = b;
3372 BUF_PUSH_2 (syntaxspec, Sword);
3373 break;
3376 case 'W':
3377 if (syntax & RE_NO_GNU_OPS)
3378 goto normal_char;
3379 laststart = b;
3380 BUF_PUSH_2 (notsyntaxspec, Sword);
3381 break;
3384 case '<':
3385 if (syntax & RE_NO_GNU_OPS)
3386 goto normal_char;
3387 BUF_PUSH (wordbeg);
3388 break;
3390 case '>':
3391 if (syntax & RE_NO_GNU_OPS)
3392 goto normal_char;
3393 BUF_PUSH (wordend);
3394 break;
3396 case 'b':
3397 if (syntax & RE_NO_GNU_OPS)
3398 goto normal_char;
3399 BUF_PUSH (wordbound);
3400 break;
3402 case 'B':
3403 if (syntax & RE_NO_GNU_OPS)
3404 goto normal_char;
3405 BUF_PUSH (notwordbound);
3406 break;
3408 case '`':
3409 if (syntax & RE_NO_GNU_OPS)
3410 goto normal_char;
3411 BUF_PUSH (begbuf);
3412 break;
3414 case '\'':
3415 if (syntax & RE_NO_GNU_OPS)
3416 goto normal_char;
3417 BUF_PUSH (endbuf);
3418 break;
3420 case '1': case '2': case '3': case '4': case '5':
3421 case '6': case '7': case '8': case '9':
3423 regnum_t reg;
3425 if (syntax & RE_NO_BK_REFS)
3426 goto normal_backslash;
3428 reg = c - '0';
3430 /* Can't back reference to a subexpression before its end. */
3431 if (reg > regnum || group_in_compile_stack (compile_stack, reg))
3432 FREE_STACK_RETURN (REG_ESUBREG);
3434 laststart = b;
3435 BUF_PUSH_2 (duplicate, reg);
3437 break;
3440 case '+':
3441 case '?':
3442 if (syntax & RE_BK_PLUS_QM)
3443 goto handle_plus;
3444 else
3445 goto normal_backslash;
3447 default:
3448 normal_backslash:
3449 /* You might think it would be useful for \ to mean
3450 not to translate; but if we don't translate it
3451 it will never match anything. */
3452 goto normal_char;
3454 break;
3457 default:
3458 /* Expects the character in `c'. */
3459 normal_char:
3460 /* If no exactn currently being built. */
3461 if (!pending_exact
3463 /* If last exactn not at current position. */
3464 || pending_exact + *pending_exact + 1 != b
3466 /* We have only one byte following the exactn for the count. */
3467 || *pending_exact >= (1 << BYTEWIDTH) - MAX_MULTIBYTE_LENGTH
3469 /* If followed by a repetition operator. */
3470 || (p != pend && (*p == '*' || *p == '^'))
3471 || ((syntax & RE_BK_PLUS_QM)
3472 ? p + 1 < pend && *p == '\\' && (p[1] == '+' || p[1] == '?')
3473 : p != pend && (*p == '+' || *p == '?'))
3474 || ((syntax & RE_INTERVALS)
3475 && ((syntax & RE_NO_BK_BRACES)
3476 ? p != pend && *p == '{'
3477 : p + 1 < pend && p[0] == '\\' && p[1] == '{')))
3479 /* Start building a new exactn. */
3481 laststart = b;
3483 BUF_PUSH_2 (exactn, 0);
3484 pending_exact = b - 1;
3487 GET_BUFFER_SPACE (MAX_MULTIBYTE_LENGTH);
3489 int len;
3491 c = TRANSLATE (c);
3492 if (multibyte)
3493 len = CHAR_STRING (c, b);
3494 else
3495 *b = c, len = 1;
3496 b += len;
3497 (*pending_exact) += len;
3500 break;
3501 } /* switch (c) */
3502 } /* while p != pend */
3505 /* Through the pattern now. */
3507 FIXUP_ALT_JUMP ();
3509 if (!COMPILE_STACK_EMPTY)
3510 FREE_STACK_RETURN (REG_EPAREN);
3512 /* If we don't want backtracking, force success
3513 the first time we reach the end of the compiled pattern. */
3514 if (syntax & RE_NO_POSIX_BACKTRACKING)
3515 BUF_PUSH (succeed);
3517 free (compile_stack.stack);
3519 /* We have succeeded; set the length of the buffer. */
3520 bufp->used = b - bufp->buffer;
3522 #ifdef DEBUG
3523 if (debug > 0)
3525 re_compile_fastmap (bufp);
3526 DEBUG_PRINT1 ("\nCompiled pattern: \n");
3527 print_compiled_pattern (bufp);
3529 debug--;
3530 #endif /* DEBUG */
3532 #ifndef MATCH_MAY_ALLOCATE
3533 /* Initialize the failure stack to the largest possible stack. This
3534 isn't necessary unless we're trying to avoid calling alloca in
3535 the search and match routines. */
3537 int num_regs = bufp->re_nsub + 1;
3539 if (fail_stack.size < re_max_failures * TYPICAL_FAILURE_SIZE)
3541 fail_stack.size = re_max_failures * TYPICAL_FAILURE_SIZE;
3543 if (! fail_stack.stack)
3544 fail_stack.stack
3545 = (fail_stack_elt_t *) malloc (fail_stack.size
3546 * sizeof (fail_stack_elt_t));
3547 else
3548 fail_stack.stack
3549 = (fail_stack_elt_t *) realloc (fail_stack.stack,
3550 (fail_stack.size
3551 * sizeof (fail_stack_elt_t)));
3554 regex_grow_registers (num_regs);
3556 #endif /* not MATCH_MAY_ALLOCATE */
3558 return REG_NOERROR;
3559 } /* regex_compile */
3561 /* Subroutines for `regex_compile'. */
3563 /* Store OP at LOC followed by two-byte integer parameter ARG. */
3565 static void
3566 store_op1 (op, loc, arg)
3567 re_opcode_t op;
3568 unsigned char *loc;
3569 int arg;
3571 *loc = (unsigned char) op;
3572 STORE_NUMBER (loc + 1, arg);
3576 /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
3578 static void
3579 store_op2 (op, loc, arg1, arg2)
3580 re_opcode_t op;
3581 unsigned char *loc;
3582 int arg1, arg2;
3584 *loc = (unsigned char) op;
3585 STORE_NUMBER (loc + 1, arg1);
3586 STORE_NUMBER (loc + 3, arg2);
3590 /* Copy the bytes from LOC to END to open up three bytes of space at LOC
3591 for OP followed by two-byte integer parameter ARG. */
3593 static void
3594 insert_op1 (op, loc, arg, end)
3595 re_opcode_t op;
3596 unsigned char *loc;
3597 int arg;
3598 unsigned char *end;
3600 register unsigned char *pfrom = end;
3601 register unsigned char *pto = end + 3;
3603 while (pfrom != loc)
3604 *--pto = *--pfrom;
3606 store_op1 (op, loc, arg);
3610 /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
3612 static void
3613 insert_op2 (op, loc, arg1, arg2, end)
3614 re_opcode_t op;
3615 unsigned char *loc;
3616 int arg1, arg2;
3617 unsigned char *end;
3619 register unsigned char *pfrom = end;
3620 register unsigned char *pto = end + 5;
3622 while (pfrom != loc)
3623 *--pto = *--pfrom;
3625 store_op2 (op, loc, arg1, arg2);
3629 /* P points to just after a ^ in PATTERN. Return true if that ^ comes
3630 after an alternative or a begin-subexpression. We assume there is at
3631 least one character before the ^. */
3633 static boolean
3634 at_begline_loc_p (pattern, p, syntax)
3635 re_char *pattern, *p;
3636 reg_syntax_t syntax;
3638 re_char *prev = p - 2;
3639 boolean prev_prev_backslash = prev > pattern && prev[-1] == '\\';
3641 return
3642 /* After a subexpression? */
3643 (*prev == '(' && (syntax & RE_NO_BK_PARENS || prev_prev_backslash))
3644 /* After an alternative? */
3645 || (*prev == '|' && (syntax & RE_NO_BK_VBAR || prev_prev_backslash))
3646 /* After a shy subexpression? */
3647 || ((syntax & RE_SHY_GROUPS) && prev - 2 >= pattern
3648 && prev[-1] == '?' && prev[-2] == '('
3649 && (syntax & RE_NO_BK_PARENS
3650 || (prev - 3 >= pattern && prev[-3] == '\\')));
3654 /* The dual of at_begline_loc_p. This one is for $. We assume there is
3655 at least one character after the $, i.e., `P < PEND'. */
3657 static boolean
3658 at_endline_loc_p (p, pend, syntax)
3659 re_char *p, *pend;
3660 reg_syntax_t syntax;
3662 re_char *next = p;
3663 boolean next_backslash = *next == '\\';
3664 re_char *next_next = p + 1 < pend ? p + 1 : 0;
3666 return
3667 /* Before a subexpression? */
3668 (syntax & RE_NO_BK_PARENS ? *next == ')'
3669 : next_backslash && next_next && *next_next == ')')
3670 /* Before an alternative? */
3671 || (syntax & RE_NO_BK_VBAR ? *next == '|'
3672 : next_backslash && next_next && *next_next == '|');
3676 /* Returns true if REGNUM is in one of COMPILE_STACK's elements and
3677 false if it's not. */
3679 static boolean
3680 group_in_compile_stack (compile_stack, regnum)
3681 compile_stack_type compile_stack;
3682 regnum_t regnum;
3684 int this_element;
3686 for (this_element = compile_stack.avail - 1;
3687 this_element >= 0;
3688 this_element--)
3689 if (compile_stack.stack[this_element].regnum == regnum)
3690 return true;
3692 return false;
3695 /* analyse_first.
3696 If fastmap is non-NULL, go through the pattern and fill fastmap
3697 with all the possible leading chars. If fastmap is NULL, don't
3698 bother filling it up (obviously) and only return whether the
3699 pattern could potentially match the empty string.
3701 Return 1 if p..pend might match the empty string.
3702 Return 0 if p..pend matches at least one char.
3703 Return -1 if fastmap was not updated accurately. */
3705 static int
3706 analyse_first (p, pend, fastmap, multibyte)
3707 re_char *p, *pend;
3708 char *fastmap;
3709 const int multibyte;
3711 int j, k;
3712 boolean not;
3714 /* If all elements for base leading-codes in fastmap is set, this
3715 flag is set true. */
3716 boolean match_any_multibyte_characters = false;
3718 assert (p);
3720 /* The loop below works as follows:
3721 - It has a working-list kept in the PATTERN_STACK and which basically
3722 starts by only containing a pointer to the first operation.
3723 - If the opcode we're looking at is a match against some set of
3724 chars, then we add those chars to the fastmap and go on to the
3725 next work element from the worklist (done via `break').
3726 - If the opcode is a control operator on the other hand, we either
3727 ignore it (if it's meaningless at this point, such as `start_memory')
3728 or execute it (if it's a jump). If the jump has several destinations
3729 (i.e. `on_failure_jump'), then we push the other destination onto the
3730 worklist.
3731 We guarantee termination by ignoring backward jumps (more or less),
3732 so that `p' is monotonically increasing. More to the point, we
3733 never set `p' (or push) anything `<= p1'. */
3735 while (p < pend)
3737 /* `p1' is used as a marker of how far back a `on_failure_jump'
3738 can go without being ignored. It is normally equal to `p'
3739 (which prevents any backward `on_failure_jump') except right
3740 after a plain `jump', to allow patterns such as:
3741 0: jump 10
3742 3..9: <body>
3743 10: on_failure_jump 3
3744 as used for the *? operator. */
3745 re_char *p1 = p;
3747 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
3749 case succeed:
3750 return 1;
3751 continue;
3753 case duplicate:
3754 /* If the first character has to match a backreference, that means
3755 that the group was empty (since it already matched). Since this
3756 is the only case that interests us here, we can assume that the
3757 backreference must match the empty string. */
3758 p++;
3759 continue;
3762 /* Following are the cases which match a character. These end
3763 with `break'. */
3765 case exactn:
3766 if (fastmap)
3768 int c = RE_STRING_CHAR (p + 1, pend - p);
3770 if (SINGLE_BYTE_CHAR_P (c))
3771 fastmap[c] = 1;
3772 else
3773 fastmap[p[1]] = 1;
3775 break;
3778 case anychar:
3779 /* We could put all the chars except for \n (and maybe \0)
3780 but we don't bother since it is generally not worth it. */
3781 if (!fastmap) break;
3782 return -1;
3785 case charset_not:
3786 /* Chars beyond end of bitmap are possible matches.
3787 All the single-byte codes can occur in multibyte buffers.
3788 So any that are not listed in the charset
3789 are possible matches, even in multibyte buffers. */
3790 if (!fastmap) break;
3791 for (j = CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH;
3792 j < (1 << BYTEWIDTH); j++)
3793 fastmap[j] = 1;
3794 /* Fallthrough */
3795 case charset:
3796 if (!fastmap) break;
3797 not = (re_opcode_t) *(p - 1) == charset_not;
3798 for (j = CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH - 1, p++;
3799 j >= 0; j--)
3800 if (!!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))) ^ not)
3801 fastmap[j] = 1;
3803 if ((not && multibyte)
3804 /* Any character set can possibly contain a character
3805 which doesn't match the specified set of characters. */
3806 || (CHARSET_RANGE_TABLE_EXISTS_P (&p[-2])
3807 && CHARSET_RANGE_TABLE_BITS (&p[-2]) != 0))
3808 /* If we can match a character class, we can match
3809 any character set. */
3811 set_fastmap_for_multibyte_characters:
3812 if (match_any_multibyte_characters == false)
3814 for (j = 0x80; j < 0xA0; j++) /* XXX */
3815 if (BASE_LEADING_CODE_P (j))
3816 fastmap[j] = 1;
3817 match_any_multibyte_characters = true;
3821 else if (!not && CHARSET_RANGE_TABLE_EXISTS_P (&p[-2])
3822 && match_any_multibyte_characters == false)
3824 /* Set fastmap[I] 1 where I is a base leading code of each
3825 multibyte character in the range table. */
3826 int c, count;
3828 /* Make P points the range table. `+ 2' is to skip flag
3829 bits for a character class. */
3830 p += CHARSET_BITMAP_SIZE (&p[-2]) + 2;
3832 /* Extract the number of ranges in range table into COUNT. */
3833 EXTRACT_NUMBER_AND_INCR (count, p);
3834 for (; count > 0; count--, p += 2 * 3) /* XXX */
3836 /* Extract the start of each range. */
3837 EXTRACT_CHARACTER (c, p);
3838 j = CHAR_CHARSET (c);
3839 fastmap[CHARSET_LEADING_CODE_BASE (j)] = 1;
3842 break;
3844 case syntaxspec:
3845 case notsyntaxspec:
3846 if (!fastmap) break;
3847 #ifndef emacs
3848 not = (re_opcode_t)p[-1] == notsyntaxspec;
3849 k = *p++;
3850 for (j = 0; j < (1 << BYTEWIDTH); j++)
3851 if ((SYNTAX (j) == (enum syntaxcode) k) ^ not)
3852 fastmap[j] = 1;
3853 break;
3854 #else /* emacs */
3855 /* This match depends on text properties. These end with
3856 aborting optimizations. */
3857 return -1;
3859 case categoryspec:
3860 case notcategoryspec:
3861 if (!fastmap) break;
3862 not = (re_opcode_t)p[-1] == notcategoryspec;
3863 k = *p++;
3864 for (j = 0; j < (1 << BYTEWIDTH); j++)
3865 if ((CHAR_HAS_CATEGORY (j, k)) ^ not)
3866 fastmap[j] = 1;
3868 if (multibyte)
3869 /* Any character set can possibly contain a character
3870 whose category is K (or not). */
3871 goto set_fastmap_for_multibyte_characters;
3872 break;
3874 /* All cases after this match the empty string. These end with
3875 `continue'. */
3877 case before_dot:
3878 case at_dot:
3879 case after_dot:
3880 #endif /* !emacs */
3881 case no_op:
3882 case begline:
3883 case endline:
3884 case begbuf:
3885 case endbuf:
3886 case wordbound:
3887 case notwordbound:
3888 case wordbeg:
3889 case wordend:
3890 continue;
3893 case jump:
3894 EXTRACT_NUMBER_AND_INCR (j, p);
3895 if (j < 0)
3896 /* Backward jumps can only go back to code that we've already
3897 visited. `re_compile' should make sure this is true. */
3898 break;
3899 p += j;
3900 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p))
3902 case on_failure_jump:
3903 case on_failure_keep_string_jump:
3904 case on_failure_jump_loop:
3905 case on_failure_jump_nastyloop:
3906 case on_failure_jump_smart:
3907 p++;
3908 break;
3909 default:
3910 continue;
3912 /* Keep `p1' to allow the `on_failure_jump' we are jumping to
3913 to jump back to "just after here". */
3914 /* Fallthrough */
3916 case on_failure_jump:
3917 case on_failure_keep_string_jump:
3918 case on_failure_jump_nastyloop:
3919 case on_failure_jump_loop:
3920 case on_failure_jump_smart:
3921 EXTRACT_NUMBER_AND_INCR (j, p);
3922 if (p + j <= p1)
3923 ; /* Backward jump to be ignored. */
3924 else
3925 { /* We have to look down both arms.
3926 We first go down the "straight" path so as to minimize
3927 stack usage when going through alternatives. */
3928 int r = analyse_first (p, pend, fastmap, multibyte);
3929 if (r) return r;
3930 p += j;
3932 continue;
3935 case jump_n:
3936 /* This code simply does not properly handle forward jump_n. */
3937 DEBUG_STATEMENT (EXTRACT_NUMBER (j, p); assert (j < 0));
3938 p += 4;
3939 /* jump_n can either jump or fall through. The (backward) jump
3940 case has already been handled, so we only need to look at the
3941 fallthrough case. */
3942 continue;
3944 case succeed_n:
3945 /* If N == 0, it should be an on_failure_jump_loop instead. */
3946 DEBUG_STATEMENT (EXTRACT_NUMBER (j, p + 2); assert (j > 0));
3947 p += 4;
3948 /* We only care about one iteration of the loop, so we don't
3949 need to consider the case where this behaves like an
3950 on_failure_jump. */
3951 continue;
3954 case set_number_at:
3955 p += 4;
3956 continue;
3959 case start_memory:
3960 case stop_memory:
3961 p += 1;
3962 continue;
3965 default:
3966 abort (); /* We have listed all the cases. */
3967 } /* switch *p++ */
3969 /* Getting here means we have found the possible starting
3970 characters for one path of the pattern -- and that the empty
3971 string does not match. We need not follow this path further. */
3972 return 0;
3973 } /* while p */
3975 /* We reached the end without matching anything. */
3976 return 1;
3978 } /* analyse_first */
3980 /* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
3981 BUFP. A fastmap records which of the (1 << BYTEWIDTH) possible
3982 characters can start a string that matches the pattern. This fastmap
3983 is used by re_search to skip quickly over impossible starting points.
3985 Character codes above (1 << BYTEWIDTH) are not represented in the
3986 fastmap, but the leading codes are represented. Thus, the fastmap
3987 indicates which character sets could start a match.
3989 The caller must supply the address of a (1 << BYTEWIDTH)-byte data
3990 area as BUFP->fastmap.
3992 We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
3993 the pattern buffer.
3995 Returns 0 if we succeed, -2 if an internal error. */
3998 re_compile_fastmap (bufp)
3999 struct re_pattern_buffer *bufp;
4001 char *fastmap = bufp->fastmap;
4002 int analysis;
4004 assert (fastmap && bufp->buffer);
4006 bzero (fastmap, 1 << BYTEWIDTH); /* Assume nothing's valid. */
4007 bufp->fastmap_accurate = 1; /* It will be when we're done. */
4009 analysis = analyse_first (bufp->buffer, bufp->buffer + bufp->used,
4010 fastmap, RE_MULTIBYTE_P (bufp));
4011 bufp->can_be_null = (analysis != 0);
4012 return 0;
4013 } /* re_compile_fastmap */
4015 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
4016 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
4017 this memory for recording register information. STARTS and ENDS
4018 must be allocated using the malloc library routine, and must each
4019 be at least NUM_REGS * sizeof (regoff_t) bytes long.
4021 If NUM_REGS == 0, then subsequent matches should allocate their own
4022 register data.
4024 Unless this function is called, the first search or match using
4025 PATTERN_BUFFER will allocate its own register data, without
4026 freeing the old data. */
4028 void
4029 re_set_registers (bufp, regs, num_regs, starts, ends)
4030 struct re_pattern_buffer *bufp;
4031 struct re_registers *regs;
4032 unsigned num_regs;
4033 regoff_t *starts, *ends;
4035 if (num_regs)
4037 bufp->regs_allocated = REGS_REALLOCATE;
4038 regs->num_regs = num_regs;
4039 regs->start = starts;
4040 regs->end = ends;
4042 else
4044 bufp->regs_allocated = REGS_UNALLOCATED;
4045 regs->num_regs = 0;
4046 regs->start = regs->end = (regoff_t *) 0;
4049 WEAK_ALIAS (__re_set_registers, re_set_registers)
4051 /* Searching routines. */
4053 /* Like re_search_2, below, but only one string is specified, and
4054 doesn't let you say where to stop matching. */
4057 re_search (bufp, string, size, startpos, range, regs)
4058 struct re_pattern_buffer *bufp;
4059 const char *string;
4060 int size, startpos, range;
4061 struct re_registers *regs;
4063 return re_search_2 (bufp, NULL, 0, string, size, startpos, range,
4064 regs, size);
4066 WEAK_ALIAS (__re_search, re_search)
4068 /* Head address of virtual concatenation of string. */
4069 #define HEAD_ADDR_VSTRING(P) \
4070 (((P) >= size1 ? string2 : string1))
4072 /* End address of virtual concatenation of string. */
4073 #define STOP_ADDR_VSTRING(P) \
4074 (((P) >= size1 ? string2 + size2 : string1 + size1))
4076 /* Address of POS in the concatenation of virtual string. */
4077 #define POS_ADDR_VSTRING(POS) \
4078 (((POS) >= size1 ? string2 - size1 : string1) + (POS))
4080 /* Using the compiled pattern in BUFP->buffer, first tries to match the
4081 virtual concatenation of STRING1 and STRING2, starting first at index
4082 STARTPOS, then at STARTPOS + 1, and so on.
4084 STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
4086 RANGE is how far to scan while trying to match. RANGE = 0 means try
4087 only at STARTPOS; in general, the last start tried is STARTPOS +
4088 RANGE.
4090 In REGS, return the indices of the virtual concatenation of STRING1
4091 and STRING2 that matched the entire BUFP->buffer and its contained
4092 subexpressions.
4094 Do not consider matching one past the index STOP in the virtual
4095 concatenation of STRING1 and STRING2.
4097 We return either the position in the strings at which the match was
4098 found, -1 if no match, or -2 if error (such as failure
4099 stack overflow). */
4102 re_search_2 (bufp, str1, size1, str2, size2, startpos, range, regs, stop)
4103 struct re_pattern_buffer *bufp;
4104 const char *str1, *str2;
4105 int size1, size2;
4106 int startpos;
4107 int range;
4108 struct re_registers *regs;
4109 int stop;
4111 int val;
4112 re_char *string1 = (re_char*) str1;
4113 re_char *string2 = (re_char*) str2;
4114 register char *fastmap = bufp->fastmap;
4115 register RE_TRANSLATE_TYPE translate = bufp->translate;
4116 int total_size = size1 + size2;
4117 int endpos = startpos + range;
4118 boolean anchored_start;
4120 /* Nonzero if we have to concern multibyte character. */
4121 const boolean multibyte = RE_MULTIBYTE_P (bufp);
4123 /* Check for out-of-range STARTPOS. */
4124 if (startpos < 0 || startpos > total_size)
4125 return -1;
4127 /* Fix up RANGE if it might eventually take us outside
4128 the virtual concatenation of STRING1 and STRING2.
4129 Make sure we won't move STARTPOS below 0 or above TOTAL_SIZE. */
4130 if (endpos < 0)
4131 range = 0 - startpos;
4132 else if (endpos > total_size)
4133 range = total_size - startpos;
4135 /* If the search isn't to be a backwards one, don't waste time in a
4136 search for a pattern anchored at beginning of buffer. */
4137 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == begbuf && range > 0)
4139 if (startpos > 0)
4140 return -1;
4141 else
4142 range = 0;
4145 #ifdef emacs
4146 /* In a forward search for something that starts with \=.
4147 don't keep searching past point. */
4148 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == at_dot && range > 0)
4150 range = PT_BYTE - BEGV_BYTE - startpos;
4151 if (range < 0)
4152 return -1;
4154 #endif /* emacs */
4156 /* Update the fastmap now if not correct already. */
4157 if (fastmap && !bufp->fastmap_accurate)
4158 re_compile_fastmap (bufp);
4160 /* See whether the pattern is anchored. */
4161 anchored_start = (bufp->buffer[0] == begline);
4163 #ifdef emacs
4164 gl_state.object = re_match_object;
4166 int charpos = SYNTAX_TABLE_BYTE_TO_CHAR (POS_AS_IN_BUFFER (startpos));
4168 SETUP_SYNTAX_TABLE_FOR_OBJECT (re_match_object, charpos, 1);
4170 #endif
4172 /* Loop through the string, looking for a place to start matching. */
4173 for (;;)
4175 /* If the pattern is anchored,
4176 skip quickly past places we cannot match.
4177 We don't bother to treat startpos == 0 specially
4178 because that case doesn't repeat. */
4179 if (anchored_start && startpos > 0)
4181 if (! ((startpos <= size1 ? string1[startpos - 1]
4182 : string2[startpos - size1 - 1])
4183 == '\n'))
4184 goto advance;
4187 /* If a fastmap is supplied, skip quickly over characters that
4188 cannot be the start of a match. If the pattern can match the
4189 null string, however, we don't need to skip characters; we want
4190 the first null string. */
4191 if (fastmap && startpos < total_size && !bufp->can_be_null)
4193 register re_char *d;
4194 register re_wchar_t buf_ch;
4196 d = POS_ADDR_VSTRING (startpos);
4198 if (range > 0) /* Searching forwards. */
4200 register int lim = 0;
4201 int irange = range;
4203 if (startpos < size1 && startpos + range >= size1)
4204 lim = range - (size1 - startpos);
4206 /* Written out as an if-else to avoid testing `translate'
4207 inside the loop. */
4208 if (RE_TRANSLATE_P (translate))
4210 if (multibyte)
4211 while (range > lim)
4213 int buf_charlen;
4215 buf_ch = STRING_CHAR_AND_LENGTH (d, range - lim,
4216 buf_charlen);
4218 buf_ch = RE_TRANSLATE (translate, buf_ch);
4219 if (buf_ch >= 0400
4220 || fastmap[buf_ch])
4221 break;
4223 range -= buf_charlen;
4224 d += buf_charlen;
4226 else
4227 while (range > lim
4228 && !fastmap[RE_TRANSLATE (translate, *d)])
4230 d++;
4231 range--;
4234 else
4235 while (range > lim && !fastmap[*d])
4237 d++;
4238 range--;
4241 startpos += irange - range;
4243 else /* Searching backwards. */
4245 int room = (startpos >= size1
4246 ? size2 + size1 - startpos
4247 : size1 - startpos);
4248 buf_ch = RE_STRING_CHAR (d, room);
4249 buf_ch = TRANSLATE (buf_ch);
4251 if (! (buf_ch >= 0400
4252 || fastmap[buf_ch]))
4253 goto advance;
4257 /* If can't match the null string, and that's all we have left, fail. */
4258 if (range >= 0 && startpos == total_size && fastmap
4259 && !bufp->can_be_null)
4260 return -1;
4262 val = re_match_2_internal (bufp, string1, size1, string2, size2,
4263 startpos, regs, stop);
4264 #ifndef REGEX_MALLOC
4265 # ifdef C_ALLOCA
4266 alloca (0);
4267 # endif
4268 #endif
4270 if (val >= 0)
4271 return startpos;
4273 if (val == -2)
4274 return -2;
4276 advance:
4277 if (!range)
4278 break;
4279 else if (range > 0)
4281 /* Update STARTPOS to the next character boundary. */
4282 if (multibyte)
4284 re_char *p = POS_ADDR_VSTRING (startpos);
4285 re_char *pend = STOP_ADDR_VSTRING (startpos);
4286 int len = MULTIBYTE_FORM_LENGTH (p, pend - p);
4288 range -= len;
4289 if (range < 0)
4290 break;
4291 startpos += len;
4293 else
4295 range--;
4296 startpos++;
4299 else
4301 range++;
4302 startpos--;
4304 /* Update STARTPOS to the previous character boundary. */
4305 if (multibyte)
4307 re_char *p = POS_ADDR_VSTRING (startpos) + 1;
4308 re_char *p0 = p;
4309 re_char *phead = HEAD_ADDR_VSTRING (startpos);
4311 /* Find the head of multibyte form. */
4312 PREV_CHAR_BOUNDARY (p, phead);
4313 range += p0 - 1 - p;
4314 if (range > 0)
4315 break;
4317 startpos -= p0 - 1 - p;
4321 return -1;
4322 } /* re_search_2 */
4323 WEAK_ALIAS (__re_search_2, re_search_2)
4325 /* Declarations and macros for re_match_2. */
4327 static int bcmp_translate _RE_ARGS((re_char *s1, re_char *s2,
4328 register int len,
4329 RE_TRANSLATE_TYPE translate,
4330 const int multibyte));
4332 /* This converts PTR, a pointer into one of the search strings `string1'
4333 and `string2' into an offset from the beginning of that string. */
4334 #define POINTER_TO_OFFSET(ptr) \
4335 (FIRST_STRING_P (ptr) \
4336 ? ((regoff_t) ((ptr) - string1)) \
4337 : ((regoff_t) ((ptr) - string2 + size1)))
4339 /* Call before fetching a character with *d. This switches over to
4340 string2 if necessary.
4341 Check re_match_2_internal for a discussion of why end_match_2 might
4342 not be within string2 (but be equal to end_match_1 instead). */
4343 #define PREFETCH() \
4344 while (d == dend) \
4346 /* End of string2 => fail. */ \
4347 if (dend == end_match_2) \
4348 goto fail; \
4349 /* End of string1 => advance to string2. */ \
4350 d = string2; \
4351 dend = end_match_2; \
4354 /* Call before fetching a char with *d if you already checked other limits.
4355 This is meant for use in lookahead operations like wordend, etc..
4356 where we might need to look at parts of the string that might be
4357 outside of the LIMITs (i.e past `stop'). */
4358 #define PREFETCH_NOLIMIT() \
4359 if (d == end1) \
4361 d = string2; \
4362 dend = end_match_2; \
4365 /* Test if at very beginning or at very end of the virtual concatenation
4366 of `string1' and `string2'. If only one string, it's `string2'. */
4367 #define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
4368 #define AT_STRINGS_END(d) ((d) == end2)
4371 /* Test if D points to a character which is word-constituent. We have
4372 two special cases to check for: if past the end of string1, look at
4373 the first character in string2; and if before the beginning of
4374 string2, look at the last character in string1. */
4375 #define WORDCHAR_P(d) \
4376 (SYNTAX ((d) == end1 ? *string2 \
4377 : (d) == string2 - 1 ? *(end1 - 1) : *(d)) \
4378 == Sword)
4380 /* Disabled due to a compiler bug -- see comment at case wordbound */
4382 /* The comment at case wordbound is following one, but we don't use
4383 AT_WORD_BOUNDARY anymore to support multibyte form.
4385 The DEC Alpha C compiler 3.x generates incorrect code for the
4386 test WORDCHAR_P (d - 1) != WORDCHAR_P (d) in the expansion of
4387 AT_WORD_BOUNDARY, so this code is disabled. Expanding the
4388 macro and introducing temporary variables works around the bug. */
4390 #if 0
4391 /* Test if the character before D and the one at D differ with respect
4392 to being word-constituent. */
4393 #define AT_WORD_BOUNDARY(d) \
4394 (AT_STRINGS_BEG (d) || AT_STRINGS_END (d) \
4395 || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
4396 #endif
4398 /* Free everything we malloc. */
4399 #ifdef MATCH_MAY_ALLOCATE
4400 # define FREE_VAR(var) if (var) { REGEX_FREE (var); var = NULL; } else
4401 # define FREE_VARIABLES() \
4402 do { \
4403 REGEX_FREE_STACK (fail_stack.stack); \
4404 FREE_VAR (regstart); \
4405 FREE_VAR (regend); \
4406 FREE_VAR (best_regstart); \
4407 FREE_VAR (best_regend); \
4408 } while (0)
4409 #else
4410 # define FREE_VARIABLES() ((void)0) /* Do nothing! But inhibit gcc warning. */
4411 #endif /* not MATCH_MAY_ALLOCATE */
4414 /* Optimization routines. */
4416 /* If the operation is a match against one or more chars,
4417 return a pointer to the next operation, else return NULL. */
4418 static re_char *
4419 skip_one_char (p)
4420 re_char *p;
4422 switch (SWITCH_ENUM_CAST (*p++))
4424 case anychar:
4425 break;
4427 case exactn:
4428 p += *p + 1;
4429 break;
4431 case charset_not:
4432 case charset:
4433 if (CHARSET_RANGE_TABLE_EXISTS_P (p - 1))
4435 int mcnt;
4436 p = CHARSET_RANGE_TABLE (p - 1);
4437 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4438 p = CHARSET_RANGE_TABLE_END (p, mcnt);
4440 else
4441 p += 1 + CHARSET_BITMAP_SIZE (p - 1);
4442 break;
4444 case syntaxspec:
4445 case notsyntaxspec:
4446 #ifdef emacs
4447 case categoryspec:
4448 case notcategoryspec:
4449 #endif /* emacs */
4450 p++;
4451 break;
4453 default:
4454 p = NULL;
4456 return p;
4460 /* Jump over non-matching operations. */
4461 static unsigned char *
4462 skip_noops (p, pend)
4463 unsigned char *p, *pend;
4465 int mcnt;
4466 while (p < pend)
4468 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p))
4470 case start_memory:
4471 case stop_memory:
4472 p += 2; break;
4473 case no_op:
4474 p += 1; break;
4475 case jump:
4476 p += 1;
4477 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4478 p += mcnt;
4479 break;
4480 default:
4481 return p;
4484 assert (p == pend);
4485 return p;
4488 /* Non-zero if "p1 matches something" implies "p2 fails". */
4489 static int
4490 mutually_exclusive_p (bufp, p1, p2)
4491 struct re_pattern_buffer *bufp;
4492 unsigned char *p1, *p2;
4494 re_opcode_t op2;
4495 const boolean multibyte = RE_MULTIBYTE_P (bufp);
4496 unsigned char *pend = bufp->buffer + bufp->used;
4498 assert (p1 >= bufp->buffer && p1 < pend
4499 && p2 >= bufp->buffer && p2 <= pend);
4501 /* Skip over open/close-group commands.
4502 If what follows this loop is a ...+ construct,
4503 look at what begins its body, since we will have to
4504 match at least one of that. */
4505 p2 = skip_noops (p2, pend);
4506 /* The same skip can be done for p1, except that this function
4507 is only used in the case where p1 is a simple match operator. */
4508 /* p1 = skip_noops (p1, pend); */
4510 assert (p1 >= bufp->buffer && p1 < pend
4511 && p2 >= bufp->buffer && p2 <= pend);
4513 op2 = p2 == pend ? succeed : *p2;
4515 switch (SWITCH_ENUM_CAST (op2))
4517 case succeed:
4518 case endbuf:
4519 /* If we're at the end of the pattern, we can change. */
4520 if (skip_one_char (p1))
4522 DEBUG_PRINT1 (" End of pattern: fast loop.\n");
4523 return 1;
4525 break;
4527 case endline:
4528 case exactn:
4530 register re_wchar_t c
4531 = (re_opcode_t) *p2 == endline ? '\n'
4532 : RE_STRING_CHAR (p2 + 2, pend - p2 - 2);
4534 if ((re_opcode_t) *p1 == exactn)
4536 if (c != RE_STRING_CHAR (p1 + 2, pend - p1 - 2))
4538 DEBUG_PRINT3 (" '%c' != '%c' => fast loop.\n", c, p1[2]);
4539 return 1;
4543 else if ((re_opcode_t) *p1 == charset
4544 || (re_opcode_t) *p1 == charset_not)
4546 int not = (re_opcode_t) *p1 == charset_not;
4548 /* Test if C is listed in charset (or charset_not)
4549 at `p1'. */
4550 if (SINGLE_BYTE_CHAR_P (c))
4552 if (c < CHARSET_BITMAP_SIZE (p1) * BYTEWIDTH
4553 && p1[2 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4554 not = !not;
4556 else if (CHARSET_RANGE_TABLE_EXISTS_P (p1))
4557 CHARSET_LOOKUP_RANGE_TABLE (not, c, p1);
4559 /* `not' is equal to 1 if c would match, which means
4560 that we can't change to pop_failure_jump. */
4561 if (!not)
4563 DEBUG_PRINT1 (" No match => fast loop.\n");
4564 return 1;
4567 else if ((re_opcode_t) *p1 == anychar
4568 && c == '\n')
4570 DEBUG_PRINT1 (" . != \\n => fast loop.\n");
4571 return 1;
4574 break;
4576 case charset:
4578 if ((re_opcode_t) *p1 == exactn)
4579 /* Reuse the code above. */
4580 return mutually_exclusive_p (bufp, p2, p1);
4582 /* It is hard to list up all the character in charset
4583 P2 if it includes multibyte character. Give up in
4584 such case. */
4585 else if (!multibyte || !CHARSET_RANGE_TABLE_EXISTS_P (p2))
4587 /* Now, we are sure that P2 has no range table.
4588 So, for the size of bitmap in P2, `p2[1]' is
4589 enough. But P1 may have range table, so the
4590 size of bitmap table of P1 is extracted by
4591 using macro `CHARSET_BITMAP_SIZE'.
4593 Since we know that all the character listed in
4594 P2 is ASCII, it is enough to test only bitmap
4595 table of P1. */
4597 if ((re_opcode_t) *p1 == charset)
4599 int idx;
4600 /* We win if the charset inside the loop
4601 has no overlap with the one after the loop. */
4602 for (idx = 0;
4603 (idx < (int) p2[1]
4604 && idx < CHARSET_BITMAP_SIZE (p1));
4605 idx++)
4606 if ((p2[2 + idx] & p1[2 + idx]) != 0)
4607 break;
4609 if (idx == p2[1]
4610 || idx == CHARSET_BITMAP_SIZE (p1))
4612 DEBUG_PRINT1 (" No match => fast loop.\n");
4613 return 1;
4616 else if ((re_opcode_t) *p1 == charset_not)
4618 int idx;
4619 /* We win if the charset_not inside the loop lists
4620 every character listed in the charset after. */
4621 for (idx = 0; idx < (int) p2[1]; idx++)
4622 if (! (p2[2 + idx] == 0
4623 || (idx < CHARSET_BITMAP_SIZE (p1)
4624 && ((p2[2 + idx] & ~ p1[2 + idx]) == 0))))
4625 break;
4627 if (idx == p2[1])
4629 DEBUG_PRINT1 (" No match => fast loop.\n");
4630 return 1;
4635 break;
4637 case charset_not:
4638 switch (SWITCH_ENUM_CAST (*p1))
4640 case exactn:
4641 case charset:
4642 /* Reuse the code above. */
4643 return mutually_exclusive_p (bufp, p2, p1);
4644 case charset_not:
4645 /* When we have two charset_not, it's very unlikely that
4646 they don't overlap. The union of the two sets of excluded
4647 chars should cover all possible chars, which, as a matter of
4648 fact, is virtually impossible in multibyte buffers. */
4649 break;
4651 break;
4653 case wordend:
4654 case notsyntaxspec:
4655 return ((re_opcode_t) *p1 == syntaxspec
4656 && p1[1] == (op2 == wordend ? Sword : p2[1]));
4658 case wordbeg:
4659 case syntaxspec:
4660 return ((re_opcode_t) *p1 == notsyntaxspec
4661 && p1[1] == (op2 == wordend ? Sword : p2[1]));
4663 case wordbound:
4664 return (((re_opcode_t) *p1 == notsyntaxspec
4665 || (re_opcode_t) *p1 == syntaxspec)
4666 && p1[1] == Sword);
4668 #ifdef emacs
4669 case categoryspec:
4670 return ((re_opcode_t) *p1 == notcategoryspec && p1[1] == p2[1]);
4671 case notcategoryspec:
4672 return ((re_opcode_t) *p1 == categoryspec && p1[1] == p2[1]);
4673 #endif /* emacs */
4675 default:
4679 /* Safe default. */
4680 return 0;
4684 /* Matching routines. */
4686 #ifndef emacs /* Emacs never uses this. */
4687 /* re_match is like re_match_2 except it takes only a single string. */
4690 re_match (bufp, string, size, pos, regs)
4691 struct re_pattern_buffer *bufp;
4692 const char *string;
4693 int size, pos;
4694 struct re_registers *regs;
4696 int result = re_match_2_internal (bufp, NULL, 0, (re_char*) string, size,
4697 pos, regs, size);
4698 # if defined C_ALLOCA && !defined REGEX_MALLOC
4699 alloca (0);
4700 # endif
4701 return result;
4703 WEAK_ALIAS (__re_match, re_match)
4704 #endif /* not emacs */
4706 #ifdef emacs
4707 /* In Emacs, this is the string or buffer in which we
4708 are matching. It is used for looking up syntax properties. */
4709 Lisp_Object re_match_object;
4710 #endif
4712 /* re_match_2 matches the compiled pattern in BUFP against the
4713 the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
4714 and SIZE2, respectively). We start matching at POS, and stop
4715 matching at STOP.
4717 If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
4718 store offsets for the substring each group matched in REGS. See the
4719 documentation for exactly how many groups we fill.
4721 We return -1 if no match, -2 if an internal error (such as the
4722 failure stack overflowing). Otherwise, we return the length of the
4723 matched substring. */
4726 re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
4727 struct re_pattern_buffer *bufp;
4728 const char *string1, *string2;
4729 int size1, size2;
4730 int pos;
4731 struct re_registers *regs;
4732 int stop;
4734 int result;
4736 #ifdef emacs
4737 int charpos;
4738 gl_state.object = re_match_object;
4739 charpos = SYNTAX_TABLE_BYTE_TO_CHAR (POS_AS_IN_BUFFER (pos));
4740 SETUP_SYNTAX_TABLE_FOR_OBJECT (re_match_object, charpos, 1);
4741 #endif
4743 result = re_match_2_internal (bufp, (re_char*) string1, size1,
4744 (re_char*) string2, size2,
4745 pos, regs, stop);
4746 #if defined C_ALLOCA && !defined REGEX_MALLOC
4747 alloca (0);
4748 #endif
4749 return result;
4751 WEAK_ALIAS (__re_match_2, re_match_2)
4753 /* This is a separate function so that we can force an alloca cleanup
4754 afterwards. */
4755 static int
4756 re_match_2_internal (bufp, string1, size1, string2, size2, pos, regs, stop)
4757 struct re_pattern_buffer *bufp;
4758 re_char *string1, *string2;
4759 int size1, size2;
4760 int pos;
4761 struct re_registers *regs;
4762 int stop;
4764 /* General temporaries. */
4765 int mcnt;
4766 size_t reg;
4767 boolean not;
4769 /* Just past the end of the corresponding string. */
4770 re_char *end1, *end2;
4772 /* Pointers into string1 and string2, just past the last characters in
4773 each to consider matching. */
4774 re_char *end_match_1, *end_match_2;
4776 /* Where we are in the data, and the end of the current string. */
4777 re_char *d, *dend;
4779 /* Used sometimes to remember where we were before starting matching
4780 an operator so that we can go back in case of failure. This "atomic"
4781 behavior of matching opcodes is indispensable to the correctness
4782 of the on_failure_keep_string_jump optimization. */
4783 re_char *dfail;
4785 /* Where we are in the pattern, and the end of the pattern. */
4786 re_char *p = bufp->buffer;
4787 re_char *pend = p + bufp->used;
4789 /* We use this to map every character in the string. */
4790 RE_TRANSLATE_TYPE translate = bufp->translate;
4792 /* Nonzero if we have to concern multibyte character. */
4793 const boolean multibyte = RE_MULTIBYTE_P (bufp);
4795 /* Failure point stack. Each place that can handle a failure further
4796 down the line pushes a failure point on this stack. It consists of
4797 regstart, and regend for all registers corresponding to
4798 the subexpressions we're currently inside, plus the number of such
4799 registers, and, finally, two char *'s. The first char * is where
4800 to resume scanning the pattern; the second one is where to resume
4801 scanning the strings. */
4802 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
4803 fail_stack_type fail_stack;
4804 #endif
4805 #ifdef DEBUG
4806 unsigned nfailure_points_pushed = 0, nfailure_points_popped = 0;
4807 #endif
4809 #if defined REL_ALLOC && defined REGEX_MALLOC
4810 /* This holds the pointer to the failure stack, when
4811 it is allocated relocatably. */
4812 fail_stack_elt_t *failure_stack_ptr;
4813 #endif
4815 /* We fill all the registers internally, independent of what we
4816 return, for use in backreferences. The number here includes
4817 an element for register zero. */
4818 size_t num_regs = bufp->re_nsub + 1;
4820 /* Information on the contents of registers. These are pointers into
4821 the input strings; they record just what was matched (on this
4822 attempt) by a subexpression part of the pattern, that is, the
4823 regnum-th regstart pointer points to where in the pattern we began
4824 matching and the regnum-th regend points to right after where we
4825 stopped matching the regnum-th subexpression. (The zeroth register
4826 keeps track of what the whole pattern matches.) */
4827 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
4828 re_char **regstart, **regend;
4829 #endif
4831 /* The following record the register info as found in the above
4832 variables when we find a match better than any we've seen before.
4833 This happens as we backtrack through the failure points, which in
4834 turn happens only if we have not yet matched the entire string. */
4835 unsigned best_regs_set = false;
4836 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
4837 re_char **best_regstart, **best_regend;
4838 #endif
4840 /* Logically, this is `best_regend[0]'. But we don't want to have to
4841 allocate space for that if we're not allocating space for anything
4842 else (see below). Also, we never need info about register 0 for
4843 any of the other register vectors, and it seems rather a kludge to
4844 treat `best_regend' differently than the rest. So we keep track of
4845 the end of the best match so far in a separate variable. We
4846 initialize this to NULL so that when we backtrack the first time
4847 and need to test it, it's not garbage. */
4848 re_char *match_end = NULL;
4850 #ifdef DEBUG
4851 /* Counts the total number of registers pushed. */
4852 unsigned num_regs_pushed = 0;
4853 #endif
4855 DEBUG_PRINT1 ("\n\nEntering re_match_2.\n");
4857 INIT_FAIL_STACK ();
4859 #ifdef MATCH_MAY_ALLOCATE
4860 /* Do not bother to initialize all the register variables if there are
4861 no groups in the pattern, as it takes a fair amount of time. If
4862 there are groups, we include space for register 0 (the whole
4863 pattern), even though we never use it, since it simplifies the
4864 array indexing. We should fix this. */
4865 if (bufp->re_nsub)
4867 regstart = REGEX_TALLOC (num_regs, re_char *);
4868 regend = REGEX_TALLOC (num_regs, re_char *);
4869 best_regstart = REGEX_TALLOC (num_regs, re_char *);
4870 best_regend = REGEX_TALLOC (num_regs, re_char *);
4872 if (!(regstart && regend && best_regstart && best_regend))
4874 FREE_VARIABLES ();
4875 return -2;
4878 else
4880 /* We must initialize all our variables to NULL, so that
4881 `FREE_VARIABLES' doesn't try to free them. */
4882 regstart = regend = best_regstart = best_regend = NULL;
4884 #endif /* MATCH_MAY_ALLOCATE */
4886 /* The starting position is bogus. */
4887 if (pos < 0 || pos > size1 + size2)
4889 FREE_VARIABLES ();
4890 return -1;
4893 /* Initialize subexpression text positions to -1 to mark ones that no
4894 start_memory/stop_memory has been seen for. Also initialize the
4895 register information struct. */
4896 for (reg = 1; reg < num_regs; reg++)
4897 regstart[reg] = regend[reg] = NULL;
4899 /* We move `string1' into `string2' if the latter's empty -- but not if
4900 `string1' is null. */
4901 if (size2 == 0 && string1 != NULL)
4903 string2 = string1;
4904 size2 = size1;
4905 string1 = 0;
4906 size1 = 0;
4908 end1 = string1 + size1;
4909 end2 = string2 + size2;
4911 /* `p' scans through the pattern as `d' scans through the data.
4912 `dend' is the end of the input string that `d' points within. `d'
4913 is advanced into the following input string whenever necessary, but
4914 this happens before fetching; therefore, at the beginning of the
4915 loop, `d' can be pointing at the end of a string, but it cannot
4916 equal `string2'. */
4917 if (pos >= size1)
4919 /* Only match within string2. */
4920 d = string2 + pos - size1;
4921 dend = end_match_2 = string2 + stop - size1;
4922 end_match_1 = end1; /* Just to give it a value. */
4924 else
4926 if (stop < size1)
4928 /* Only match within string1. */
4929 end_match_1 = string1 + stop;
4930 /* BEWARE!
4931 When we reach end_match_1, PREFETCH normally switches to string2.
4932 But in the present case, this means that just doing a PREFETCH
4933 makes us jump from `stop' to `gap' within the string.
4934 What we really want here is for the search to stop as
4935 soon as we hit end_match_1. That's why we set end_match_2
4936 to end_match_1 (since PREFETCH fails as soon as we hit
4937 end_match_2). */
4938 end_match_2 = end_match_1;
4940 else
4941 { /* It's important to use this code when stop == size so that
4942 moving `d' from end1 to string2 will not prevent the d == dend
4943 check from catching the end of string. */
4944 end_match_1 = end1;
4945 end_match_2 = string2 + stop - size1;
4947 d = string1 + pos;
4948 dend = end_match_1;
4951 DEBUG_PRINT1 ("The compiled pattern is: ");
4952 DEBUG_PRINT_COMPILED_PATTERN (bufp, p, pend);
4953 DEBUG_PRINT1 ("The string to match is: `");
4954 DEBUG_PRINT_DOUBLE_STRING (d, string1, size1, string2, size2);
4955 DEBUG_PRINT1 ("'\n");
4957 /* This loops over pattern commands. It exits by returning from the
4958 function if the match is complete, or it drops through if the match
4959 fails at this starting point in the input data. */
4960 for (;;)
4962 DEBUG_PRINT2 ("\n%p: ", p);
4964 if (p == pend)
4965 { /* End of pattern means we might have succeeded. */
4966 DEBUG_PRINT1 ("end of pattern ... ");
4968 /* If we haven't matched the entire string, and we want the
4969 longest match, try backtracking. */
4970 if (d != end_match_2)
4972 /* 1 if this match ends in the same string (string1 or string2)
4973 as the best previous match. */
4974 boolean same_str_p = (FIRST_STRING_P (match_end)
4975 == FIRST_STRING_P (d));
4976 /* 1 if this match is the best seen so far. */
4977 boolean best_match_p;
4979 /* AIX compiler got confused when this was combined
4980 with the previous declaration. */
4981 if (same_str_p)
4982 best_match_p = d > match_end;
4983 else
4984 best_match_p = !FIRST_STRING_P (d);
4986 DEBUG_PRINT1 ("backtracking.\n");
4988 if (!FAIL_STACK_EMPTY ())
4989 { /* More failure points to try. */
4991 /* If exceeds best match so far, save it. */
4992 if (!best_regs_set || best_match_p)
4994 best_regs_set = true;
4995 match_end = d;
4997 DEBUG_PRINT1 ("\nSAVING match as best so far.\n");
4999 for (reg = 1; reg < num_regs; reg++)
5001 best_regstart[reg] = regstart[reg];
5002 best_regend[reg] = regend[reg];
5005 goto fail;
5008 /* If no failure points, don't restore garbage. And if
5009 last match is real best match, don't restore second
5010 best one. */
5011 else if (best_regs_set && !best_match_p)
5013 restore_best_regs:
5014 /* Restore best match. It may happen that `dend ==
5015 end_match_1' while the restored d is in string2.
5016 For example, the pattern `x.*y.*z' against the
5017 strings `x-' and `y-z-', if the two strings are
5018 not consecutive in memory. */
5019 DEBUG_PRINT1 ("Restoring best registers.\n");
5021 d = match_end;
5022 dend = ((d >= string1 && d <= end1)
5023 ? end_match_1 : end_match_2);
5025 for (reg = 1; reg < num_regs; reg++)
5027 regstart[reg] = best_regstart[reg];
5028 regend[reg] = best_regend[reg];
5031 } /* d != end_match_2 */
5033 succeed_label:
5034 DEBUG_PRINT1 ("Accepting match.\n");
5036 /* If caller wants register contents data back, do it. */
5037 if (regs && !bufp->no_sub)
5039 /* Have the register data arrays been allocated? */
5040 if (bufp->regs_allocated == REGS_UNALLOCATED)
5041 { /* No. So allocate them with malloc. We need one
5042 extra element beyond `num_regs' for the `-1' marker
5043 GNU code uses. */
5044 regs->num_regs = MAX (RE_NREGS, num_regs + 1);
5045 regs->start = TALLOC (regs->num_regs, regoff_t);
5046 regs->end = TALLOC (regs->num_regs, regoff_t);
5047 if (regs->start == NULL || regs->end == NULL)
5049 FREE_VARIABLES ();
5050 return -2;
5052 bufp->regs_allocated = REGS_REALLOCATE;
5054 else if (bufp->regs_allocated == REGS_REALLOCATE)
5055 { /* Yes. If we need more elements than were already
5056 allocated, reallocate them. If we need fewer, just
5057 leave it alone. */
5058 if (regs->num_regs < num_regs + 1)
5060 regs->num_regs = num_regs + 1;
5061 RETALLOC (regs->start, regs->num_regs, regoff_t);
5062 RETALLOC (regs->end, regs->num_regs, regoff_t);
5063 if (regs->start == NULL || regs->end == NULL)
5065 FREE_VARIABLES ();
5066 return -2;
5070 else
5072 /* These braces fend off a "empty body in an else-statement"
5073 warning under GCC when assert expands to nothing. */
5074 assert (bufp->regs_allocated == REGS_FIXED);
5077 /* Convert the pointer data in `regstart' and `regend' to
5078 indices. Register zero has to be set differently,
5079 since we haven't kept track of any info for it. */
5080 if (regs->num_regs > 0)
5082 regs->start[0] = pos;
5083 regs->end[0] = POINTER_TO_OFFSET (d);
5086 /* Go through the first `min (num_regs, regs->num_regs)'
5087 registers, since that is all we initialized. */
5088 for (reg = 1; reg < MIN (num_regs, regs->num_regs); reg++)
5090 if (REG_UNSET (regstart[reg]) || REG_UNSET (regend[reg]))
5091 regs->start[reg] = regs->end[reg] = -1;
5092 else
5094 regs->start[reg]
5095 = (regoff_t) POINTER_TO_OFFSET (regstart[reg]);
5096 regs->end[reg]
5097 = (regoff_t) POINTER_TO_OFFSET (regend[reg]);
5101 /* If the regs structure we return has more elements than
5102 were in the pattern, set the extra elements to -1. If
5103 we (re)allocated the registers, this is the case,
5104 because we always allocate enough to have at least one
5105 -1 at the end. */
5106 for (reg = num_regs; reg < regs->num_regs; reg++)
5107 regs->start[reg] = regs->end[reg] = -1;
5108 } /* regs && !bufp->no_sub */
5110 DEBUG_PRINT4 ("%u failure points pushed, %u popped (%u remain).\n",
5111 nfailure_points_pushed, nfailure_points_popped,
5112 nfailure_points_pushed - nfailure_points_popped);
5113 DEBUG_PRINT2 ("%u registers pushed.\n", num_regs_pushed);
5115 mcnt = POINTER_TO_OFFSET (d) - pos;
5117 DEBUG_PRINT2 ("Returning %d from re_match_2.\n", mcnt);
5119 FREE_VARIABLES ();
5120 return mcnt;
5123 /* Otherwise match next pattern command. */
5124 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
5126 /* Ignore these. Used to ignore the n of succeed_n's which
5127 currently have n == 0. */
5128 case no_op:
5129 DEBUG_PRINT1 ("EXECUTING no_op.\n");
5130 break;
5132 case succeed:
5133 DEBUG_PRINT1 ("EXECUTING succeed.\n");
5134 goto succeed_label;
5136 /* Match the next n pattern characters exactly. The following
5137 byte in the pattern defines n, and the n bytes after that
5138 are the characters to match. */
5139 case exactn:
5140 mcnt = *p++;
5141 DEBUG_PRINT2 ("EXECUTING exactn %d.\n", mcnt);
5143 /* Remember the start point to rollback upon failure. */
5144 dfail = d;
5146 /* This is written out as an if-else so we don't waste time
5147 testing `translate' inside the loop. */
5148 if (RE_TRANSLATE_P (translate))
5150 if (multibyte)
5153 int pat_charlen, buf_charlen;
5154 unsigned int pat_ch, buf_ch;
5156 PREFETCH ();
5157 pat_ch = STRING_CHAR_AND_LENGTH (p, pend - p, pat_charlen);
5158 buf_ch = STRING_CHAR_AND_LENGTH (d, dend - d, buf_charlen);
5160 if (RE_TRANSLATE (translate, buf_ch)
5161 != pat_ch)
5163 d = dfail;
5164 goto fail;
5167 p += pat_charlen;
5168 d += buf_charlen;
5169 mcnt -= pat_charlen;
5171 while (mcnt > 0);
5172 else
5175 PREFETCH ();
5176 if (RE_TRANSLATE (translate, *d) != *p++)
5178 d = dfail;
5179 goto fail;
5181 d++;
5183 while (--mcnt);
5185 else
5189 PREFETCH ();
5190 if (*d++ != *p++)
5192 d = dfail;
5193 goto fail;
5196 while (--mcnt);
5198 break;
5201 /* Match any character except possibly a newline or a null. */
5202 case anychar:
5204 int buf_charlen;
5205 re_wchar_t buf_ch;
5207 DEBUG_PRINT1 ("EXECUTING anychar.\n");
5209 PREFETCH ();
5210 buf_ch = RE_STRING_CHAR_AND_LENGTH (d, dend - d, buf_charlen);
5211 buf_ch = TRANSLATE (buf_ch);
5213 if ((!(bufp->syntax & RE_DOT_NEWLINE)
5214 && buf_ch == '\n')
5215 || ((bufp->syntax & RE_DOT_NOT_NULL)
5216 && buf_ch == '\000'))
5217 goto fail;
5219 DEBUG_PRINT2 (" Matched `%d'.\n", *d);
5220 d += buf_charlen;
5222 break;
5225 case charset:
5226 case charset_not:
5228 register unsigned int c;
5229 boolean not = (re_opcode_t) *(p - 1) == charset_not;
5230 int len;
5232 /* Start of actual range_table, or end of bitmap if there is no
5233 range table. */
5234 re_char *range_table;
5236 /* Nonzero if there is a range table. */
5237 int range_table_exists;
5239 /* Number of ranges of range table. This is not included
5240 in the initial byte-length of the command. */
5241 int count = 0;
5243 DEBUG_PRINT2 ("EXECUTING charset%s.\n", not ? "_not" : "");
5245 range_table_exists = CHARSET_RANGE_TABLE_EXISTS_P (&p[-1]);
5247 if (range_table_exists)
5249 range_table = CHARSET_RANGE_TABLE (&p[-1]); /* Past the bitmap. */
5250 EXTRACT_NUMBER_AND_INCR (count, range_table);
5253 PREFETCH ();
5254 c = RE_STRING_CHAR_AND_LENGTH (d, dend - d, len);
5255 c = TRANSLATE (c); /* The character to match. */
5257 if (SINGLE_BYTE_CHAR_P (c))
5258 { /* Lookup bitmap. */
5259 /* Cast to `unsigned' instead of `unsigned char' in
5260 case the bit list is a full 32 bytes long. */
5261 if (c < (unsigned) (CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH)
5262 && p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
5263 not = !not;
5265 #ifdef emacs
5266 else if (range_table_exists)
5268 int class_bits = CHARSET_RANGE_TABLE_BITS (&p[-1]);
5270 if ( (class_bits & BIT_LOWER && ISLOWER (c))
5271 | (class_bits & BIT_MULTIBYTE)
5272 | (class_bits & BIT_PUNCT && ISPUNCT (c))
5273 | (class_bits & BIT_SPACE && ISSPACE (c))
5274 | (class_bits & BIT_UPPER && ISUPPER (c))
5275 | (class_bits & BIT_WORD && ISWORD (c)))
5276 not = !not;
5277 else
5278 CHARSET_LOOKUP_RANGE_TABLE_RAW (not, c, range_table, count);
5280 #endif /* emacs */
5282 if (range_table_exists)
5283 p = CHARSET_RANGE_TABLE_END (range_table, count);
5284 else
5285 p += CHARSET_BITMAP_SIZE (&p[-1]) + 1;
5287 if (!not) goto fail;
5289 d += len;
5290 break;
5294 /* The beginning of a group is represented by start_memory.
5295 The argument is the register number. The text
5296 matched within the group is recorded (in the internal
5297 registers data structure) under the register number. */
5298 case start_memory:
5299 DEBUG_PRINT2 ("EXECUTING start_memory %d:\n", *p);
5301 /* In case we need to undo this operation (via backtracking). */
5302 PUSH_FAILURE_REG ((unsigned int)*p);
5304 regstart[*p] = d;
5305 regend[*p] = NULL; /* probably unnecessary. -sm */
5306 DEBUG_PRINT2 (" regstart: %d\n", POINTER_TO_OFFSET (regstart[*p]));
5308 /* Move past the register number and inner group count. */
5309 p += 1;
5310 break;
5313 /* The stop_memory opcode represents the end of a group. Its
5314 argument is the same as start_memory's: the register number. */
5315 case stop_memory:
5316 DEBUG_PRINT2 ("EXECUTING stop_memory %d:\n", *p);
5318 assert (!REG_UNSET (regstart[*p]));
5319 /* Strictly speaking, there should be code such as:
5321 assert (REG_UNSET (regend[*p]));
5322 PUSH_FAILURE_REGSTOP ((unsigned int)*p);
5324 But the only info to be pushed is regend[*p] and it is known to
5325 be UNSET, so there really isn't anything to push.
5326 Not pushing anything, on the other hand deprives us from the
5327 guarantee that regend[*p] is UNSET since undoing this operation
5328 will not reset its value properly. This is not important since
5329 the value will only be read on the next start_memory or at
5330 the very end and both events can only happen if this stop_memory
5331 is *not* undone. */
5333 regend[*p] = d;
5334 DEBUG_PRINT2 (" regend: %d\n", POINTER_TO_OFFSET (regend[*p]));
5336 /* Move past the register number and the inner group count. */
5337 p += 1;
5338 break;
5341 /* \<digit> has been turned into a `duplicate' command which is
5342 followed by the numeric value of <digit> as the register number. */
5343 case duplicate:
5345 register re_char *d2, *dend2;
5346 int regno = *p++; /* Get which register to match against. */
5347 DEBUG_PRINT2 ("EXECUTING duplicate %d.\n", regno);
5349 /* Can't back reference a group which we've never matched. */
5350 if (REG_UNSET (regstart[regno]) || REG_UNSET (regend[regno]))
5351 goto fail;
5353 /* Where in input to try to start matching. */
5354 d2 = regstart[regno];
5356 /* Remember the start point to rollback upon failure. */
5357 dfail = d;
5359 /* Where to stop matching; if both the place to start and
5360 the place to stop matching are in the same string, then
5361 set to the place to stop, otherwise, for now have to use
5362 the end of the first string. */
5364 dend2 = ((FIRST_STRING_P (regstart[regno])
5365 == FIRST_STRING_P (regend[regno]))
5366 ? regend[regno] : end_match_1);
5367 for (;;)
5369 /* If necessary, advance to next segment in register
5370 contents. */
5371 while (d2 == dend2)
5373 if (dend2 == end_match_2) break;
5374 if (dend2 == regend[regno]) break;
5376 /* End of string1 => advance to string2. */
5377 d2 = string2;
5378 dend2 = regend[regno];
5380 /* At end of register contents => success */
5381 if (d2 == dend2) break;
5383 /* If necessary, advance to next segment in data. */
5384 PREFETCH ();
5386 /* How many characters left in this segment to match. */
5387 mcnt = dend - d;
5389 /* Want how many consecutive characters we can match in
5390 one shot, so, if necessary, adjust the count. */
5391 if (mcnt > dend2 - d2)
5392 mcnt = dend2 - d2;
5394 /* Compare that many; failure if mismatch, else move
5395 past them. */
5396 if (RE_TRANSLATE_P (translate)
5397 ? bcmp_translate (d, d2, mcnt, translate, multibyte)
5398 : memcmp (d, d2, mcnt))
5400 d = dfail;
5401 goto fail;
5403 d += mcnt, d2 += mcnt;
5406 break;
5409 /* begline matches the empty string at the beginning of the string
5410 (unless `not_bol' is set in `bufp'), and after newlines. */
5411 case begline:
5412 DEBUG_PRINT1 ("EXECUTING begline.\n");
5414 if (AT_STRINGS_BEG (d))
5416 if (!bufp->not_bol) break;
5418 else
5420 unsigned char c;
5421 GET_CHAR_BEFORE_2 (c, d, string1, end1, string2, end2);
5422 if (c == '\n')
5423 break;
5425 /* In all other cases, we fail. */
5426 goto fail;
5429 /* endline is the dual of begline. */
5430 case endline:
5431 DEBUG_PRINT1 ("EXECUTING endline.\n");
5433 if (AT_STRINGS_END (d))
5435 if (!bufp->not_eol) break;
5437 else
5439 PREFETCH_NOLIMIT ();
5440 if (*d == '\n')
5441 break;
5443 goto fail;
5446 /* Match at the very beginning of the data. */
5447 case begbuf:
5448 DEBUG_PRINT1 ("EXECUTING begbuf.\n");
5449 if (AT_STRINGS_BEG (d))
5450 break;
5451 goto fail;
5454 /* Match at the very end of the data. */
5455 case endbuf:
5456 DEBUG_PRINT1 ("EXECUTING endbuf.\n");
5457 if (AT_STRINGS_END (d))
5458 break;
5459 goto fail;
5462 /* on_failure_keep_string_jump is used to optimize `.*\n'. It
5463 pushes NULL as the value for the string on the stack. Then
5464 `POP_FAILURE_POINT' will keep the current value for the
5465 string, instead of restoring it. To see why, consider
5466 matching `foo\nbar' against `.*\n'. The .* matches the foo;
5467 then the . fails against the \n. But the next thing we want
5468 to do is match the \n against the \n; if we restored the
5469 string value, we would be back at the foo.
5471 Because this is used only in specific cases, we don't need to
5472 check all the things that `on_failure_jump' does, to make
5473 sure the right things get saved on the stack. Hence we don't
5474 share its code. The only reason to push anything on the
5475 stack at all is that otherwise we would have to change
5476 `anychar's code to do something besides goto fail in this
5477 case; that seems worse than this. */
5478 case on_failure_keep_string_jump:
5479 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5480 DEBUG_PRINT3 ("EXECUTING on_failure_keep_string_jump %d (to %p):\n",
5481 mcnt, p + mcnt);
5483 PUSH_FAILURE_POINT (p - 3, NULL);
5484 break;
5486 /* A nasty loop is introduced by the non-greedy *? and +?.
5487 With such loops, the stack only ever contains one failure point
5488 at a time, so that a plain on_failure_jump_loop kind of
5489 cycle detection cannot work. Worse yet, such a detection
5490 can not only fail to detect a cycle, but it can also wrongly
5491 detect a cycle (between different instantiations of the same
5492 loop).
5493 So the method used for those nasty loops is a little different:
5494 We use a special cycle-detection-stack-frame which is pushed
5495 when the on_failure_jump_nastyloop failure-point is *popped*.
5496 This special frame thus marks the beginning of one iteration
5497 through the loop and we can hence easily check right here
5498 whether something matched between the beginning and the end of
5499 the loop. */
5500 case on_failure_jump_nastyloop:
5501 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5502 DEBUG_PRINT3 ("EXECUTING on_failure_jump_nastyloop %d (to %p):\n",
5503 mcnt, p + mcnt);
5505 assert ((re_opcode_t)p[-4] == no_op);
5507 int cycle = 0;
5508 CHECK_INFINITE_LOOP (p - 4, d);
5509 if (!cycle)
5510 /* If there's a cycle, just continue without pushing
5511 this failure point. The failure point is the "try again"
5512 option, which shouldn't be tried.
5513 We want (x?)*?y\1z to match both xxyz and xxyxz. */
5514 PUSH_FAILURE_POINT (p - 3, d);
5516 break;
5518 /* Simple loop detecting on_failure_jump: just check on the
5519 failure stack if the same spot was already hit earlier. */
5520 case on_failure_jump_loop:
5521 on_failure:
5522 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5523 DEBUG_PRINT3 ("EXECUTING on_failure_jump_loop %d (to %p):\n",
5524 mcnt, p + mcnt);
5526 int cycle = 0;
5527 CHECK_INFINITE_LOOP (p - 3, d);
5528 if (cycle)
5529 /* If there's a cycle, get out of the loop, as if the matching
5530 had failed. We used to just `goto fail' here, but that was
5531 aborting the search a bit too early: we want to keep the
5532 empty-loop-match and keep matching after the loop.
5533 We want (x?)*y\1z to match both xxyz and xxyxz. */
5534 p += mcnt;
5535 else
5536 PUSH_FAILURE_POINT (p - 3, d);
5538 break;
5541 /* Uses of on_failure_jump:
5543 Each alternative starts with an on_failure_jump that points
5544 to the beginning of the next alternative. Each alternative
5545 except the last ends with a jump that in effect jumps past
5546 the rest of the alternatives. (They really jump to the
5547 ending jump of the following alternative, because tensioning
5548 these jumps is a hassle.)
5550 Repeats start with an on_failure_jump that points past both
5551 the repetition text and either the following jump or
5552 pop_failure_jump back to this on_failure_jump. */
5553 case on_failure_jump:
5554 IMMEDIATE_QUIT_CHECK;
5555 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5556 DEBUG_PRINT3 ("EXECUTING on_failure_jump %d (to %p):\n",
5557 mcnt, p + mcnt);
5559 PUSH_FAILURE_POINT (p -3, d);
5560 break;
5562 /* This operation is used for greedy *.
5563 Compare the beginning of the repeat with what in the
5564 pattern follows its end. If we can establish that there
5565 is nothing that they would both match, i.e., that we
5566 would have to backtrack because of (as in, e.g., `a*a')
5567 then we can use a non-backtracking loop based on
5568 on_failure_keep_string_jump instead of on_failure_jump. */
5569 case on_failure_jump_smart:
5570 IMMEDIATE_QUIT_CHECK;
5571 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5572 DEBUG_PRINT3 ("EXECUTING on_failure_jump_smart %d (to %p).\n",
5573 mcnt, p + mcnt);
5575 re_char *p1 = p; /* Next operation. */
5576 /* Here, we discard `const', making re_match non-reentrant. */
5577 unsigned char *p2 = (unsigned char*) p + mcnt; /* Jump dest. */
5578 unsigned char *p3 = (unsigned char*) p - 3; /* opcode location. */
5580 p -= 3; /* Reset so that we will re-execute the
5581 instruction once it's been changed. */
5583 EXTRACT_NUMBER (mcnt, p2 - 2);
5585 /* Ensure this is a indeed the trivial kind of loop
5586 we are expecting. */
5587 assert (skip_one_char (p1) == p2 - 3);
5588 assert ((re_opcode_t) p2[-3] == jump && p2 + mcnt == p);
5589 DEBUG_STATEMENT (debug += 2);
5590 if (mutually_exclusive_p (bufp, p1, p2))
5592 /* Use a fast `on_failure_keep_string_jump' loop. */
5593 DEBUG_PRINT1 (" smart exclusive => fast loop.\n");
5594 *p3 = (unsigned char) on_failure_keep_string_jump;
5595 STORE_NUMBER (p2 - 2, mcnt + 3);
5597 else
5599 /* Default to a safe `on_failure_jump' loop. */
5600 DEBUG_PRINT1 (" smart default => slow loop.\n");
5601 *p3 = (unsigned char) on_failure_jump;
5603 DEBUG_STATEMENT (debug -= 2);
5605 break;
5607 /* Unconditionally jump (without popping any failure points). */
5608 case jump:
5609 unconditional_jump:
5610 IMMEDIATE_QUIT_CHECK;
5611 EXTRACT_NUMBER_AND_INCR (mcnt, p); /* Get the amount to jump. */
5612 DEBUG_PRINT2 ("EXECUTING jump %d ", mcnt);
5613 p += mcnt; /* Do the jump. */
5614 DEBUG_PRINT2 ("(to %p).\n", p);
5615 break;
5618 /* Have to succeed matching what follows at least n times.
5619 After that, handle like `on_failure_jump'. */
5620 case succeed_n:
5621 /* Signedness doesn't matter since we only compare MCNT to 0. */
5622 EXTRACT_NUMBER (mcnt, p + 2);
5623 DEBUG_PRINT2 ("EXECUTING succeed_n %d.\n", mcnt);
5625 /* Originally, mcnt is how many times we HAVE to succeed. */
5626 if (mcnt != 0)
5628 /* Here, we discard `const', making re_match non-reentrant. */
5629 unsigned char *p2 = (unsigned char*) p + 2; /* counter loc. */
5630 mcnt--;
5631 p += 4;
5632 PUSH_NUMBER (p2, mcnt);
5634 else
5635 /* The two bytes encoding mcnt == 0 are two no_op opcodes. */
5636 goto on_failure;
5637 break;
5639 case jump_n:
5640 /* Signedness doesn't matter since we only compare MCNT to 0. */
5641 EXTRACT_NUMBER (mcnt, p + 2);
5642 DEBUG_PRINT2 ("EXECUTING jump_n %d.\n", mcnt);
5644 /* Originally, this is how many times we CAN jump. */
5645 if (mcnt != 0)
5647 /* Here, we discard `const', making re_match non-reentrant. */
5648 unsigned char *p2 = (unsigned char*) p + 2; /* counter loc. */
5649 mcnt--;
5650 PUSH_NUMBER (p2, mcnt);
5651 goto unconditional_jump;
5653 /* If don't have to jump any more, skip over the rest of command. */
5654 else
5655 p += 4;
5656 break;
5658 case set_number_at:
5660 unsigned char *p2; /* Location of the counter. */
5661 DEBUG_PRINT1 ("EXECUTING set_number_at.\n");
5663 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5664 /* Here, we discard `const', making re_match non-reentrant. */
5665 p2 = (unsigned char*) p + mcnt;
5666 /* Signedness doesn't matter since we only copy MCNT's bits . */
5667 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5668 DEBUG_PRINT3 (" Setting %p to %d.\n", p2, mcnt);
5669 PUSH_NUMBER (p2, mcnt);
5670 break;
5673 case wordbound:
5674 case notwordbound:
5675 not = (re_opcode_t) *(p - 1) == notwordbound;
5676 DEBUG_PRINT2 ("EXECUTING %swordbound.\n", not?"not":"");
5678 /* We SUCCEED (or FAIL) in one of the following cases: */
5680 /* Case 1: D is at the beginning or the end of string. */
5681 if (AT_STRINGS_BEG (d) || AT_STRINGS_END (d))
5682 not = !not;
5683 else
5685 /* C1 is the character before D, S1 is the syntax of C1, C2
5686 is the character at D, and S2 is the syntax of C2. */
5687 re_wchar_t c1, c2;
5688 int s1, s2;
5689 #ifdef emacs
5690 int offset = PTR_TO_OFFSET (d - 1);
5691 int charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5692 UPDATE_SYNTAX_TABLE (charpos);
5693 #endif
5694 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5695 s1 = SYNTAX (c1);
5696 #ifdef emacs
5697 UPDATE_SYNTAX_TABLE_FORWARD (charpos + 1);
5698 #endif
5699 PREFETCH_NOLIMIT ();
5700 c2 = RE_STRING_CHAR (d, dend - d);
5701 s2 = SYNTAX (c2);
5703 if (/* Case 2: Only one of S1 and S2 is Sword. */
5704 ((s1 == Sword) != (s2 == Sword))
5705 /* Case 3: Both of S1 and S2 are Sword, and macro
5706 WORD_BOUNDARY_P (C1, C2) returns nonzero. */
5707 || ((s1 == Sword) && WORD_BOUNDARY_P (c1, c2)))
5708 not = !not;
5710 if (not)
5711 break;
5712 else
5713 goto fail;
5715 case wordbeg:
5716 DEBUG_PRINT1 ("EXECUTING wordbeg.\n");
5718 /* We FAIL in one of the following cases: */
5720 /* Case 1: D is at the end of string. */
5721 if (AT_STRINGS_END (d))
5722 goto fail;
5723 else
5725 /* C1 is the character before D, S1 is the syntax of C1, C2
5726 is the character at D, and S2 is the syntax of C2. */
5727 re_wchar_t c1, c2;
5728 int s1, s2;
5729 #ifdef emacs
5730 int offset = PTR_TO_OFFSET (d);
5731 int charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5732 UPDATE_SYNTAX_TABLE (charpos);
5733 #endif
5734 PREFETCH ();
5735 c2 = RE_STRING_CHAR (d, dend - d);
5736 s2 = SYNTAX (c2);
5738 /* Case 2: S2 is not Sword. */
5739 if (s2 != Sword)
5740 goto fail;
5742 /* Case 3: D is not at the beginning of string ... */
5743 if (!AT_STRINGS_BEG (d))
5745 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5746 #ifdef emacs
5747 UPDATE_SYNTAX_TABLE_BACKWARD (charpos - 1);
5748 #endif
5749 s1 = SYNTAX (c1);
5751 /* ... and S1 is Sword, and WORD_BOUNDARY_P (C1, C2)
5752 returns 0. */
5753 if ((s1 == Sword) && !WORD_BOUNDARY_P (c1, c2))
5754 goto fail;
5757 break;
5759 case wordend:
5760 DEBUG_PRINT1 ("EXECUTING wordend.\n");
5762 /* We FAIL in one of the following cases: */
5764 /* Case 1: D is at the beginning of string. */
5765 if (AT_STRINGS_BEG (d))
5766 goto fail;
5767 else
5769 /* C1 is the character before D, S1 is the syntax of C1, C2
5770 is the character at D, and S2 is the syntax of C2. */
5771 re_wchar_t c1, c2;
5772 int s1, s2;
5773 #ifdef emacs
5774 int offset = PTR_TO_OFFSET (d) - 1;
5775 int charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5776 UPDATE_SYNTAX_TABLE (charpos);
5777 #endif
5778 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5779 s1 = SYNTAX (c1);
5781 /* Case 2: S1 is not Sword. */
5782 if (s1 != Sword)
5783 goto fail;
5785 /* Case 3: D is not at the end of string ... */
5786 if (!AT_STRINGS_END (d))
5788 PREFETCH_NOLIMIT ();
5789 c2 = RE_STRING_CHAR (d, dend - d);
5790 #ifdef emacs
5791 UPDATE_SYNTAX_TABLE_FORWARD (charpos);
5792 #endif
5793 s2 = SYNTAX (c2);
5795 /* ... and S2 is Sword, and WORD_BOUNDARY_P (C1, C2)
5796 returns 0. */
5797 if ((s2 == Sword) && !WORD_BOUNDARY_P (c1, c2))
5798 goto fail;
5801 break;
5803 case syntaxspec:
5804 case notsyntaxspec:
5805 not = (re_opcode_t) *(p - 1) == notsyntaxspec;
5806 mcnt = *p++;
5807 DEBUG_PRINT3 ("EXECUTING %ssyntaxspec %d.\n", not?"not":"", mcnt);
5808 PREFETCH ();
5809 #ifdef emacs
5811 int offset = PTR_TO_OFFSET (d);
5812 int pos1 = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5813 UPDATE_SYNTAX_TABLE (pos1);
5815 #endif
5817 int len;
5818 re_wchar_t c;
5820 c = RE_STRING_CHAR_AND_LENGTH (d, dend - d, len);
5822 if ((SYNTAX (c) != (enum syntaxcode) mcnt) ^ not)
5823 goto fail;
5824 d += len;
5826 break;
5828 #ifdef emacs
5829 case before_dot:
5830 DEBUG_PRINT1 ("EXECUTING before_dot.\n");
5831 if (PTR_BYTE_POS (d) >= PT_BYTE)
5832 goto fail;
5833 break;
5835 case at_dot:
5836 DEBUG_PRINT1 ("EXECUTING at_dot.\n");
5837 if (PTR_BYTE_POS (d) != PT_BYTE)
5838 goto fail;
5839 break;
5841 case after_dot:
5842 DEBUG_PRINT1 ("EXECUTING after_dot.\n");
5843 if (PTR_BYTE_POS (d) <= PT_BYTE)
5844 goto fail;
5845 break;
5847 case categoryspec:
5848 case notcategoryspec:
5849 not = (re_opcode_t) *(p - 1) == notcategoryspec;
5850 mcnt = *p++;
5851 DEBUG_PRINT3 ("EXECUTING %scategoryspec %d.\n", not?"not":"", mcnt);
5852 PREFETCH ();
5854 int len;
5855 re_wchar_t c;
5857 c = RE_STRING_CHAR_AND_LENGTH (d, dend - d, len);
5859 if ((!CHAR_HAS_CATEGORY (c, mcnt)) ^ not)
5860 goto fail;
5861 d += len;
5863 break;
5865 #endif /* emacs */
5867 default:
5868 abort ();
5870 continue; /* Successfully executed one pattern command; keep going. */
5873 /* We goto here if a matching operation fails. */
5874 fail:
5875 IMMEDIATE_QUIT_CHECK;
5876 if (!FAIL_STACK_EMPTY ())
5878 re_char *str, *pat;
5879 /* A restart point is known. Restore to that state. */
5880 DEBUG_PRINT1 ("\nFAIL:\n");
5881 POP_FAILURE_POINT (str, pat);
5882 switch (SWITCH_ENUM_CAST ((re_opcode_t) *pat++))
5884 case on_failure_keep_string_jump:
5885 assert (str == NULL);
5886 goto continue_failure_jump;
5888 case on_failure_jump_nastyloop:
5889 assert ((re_opcode_t)pat[-2] == no_op);
5890 PUSH_FAILURE_POINT (pat - 2, str);
5891 /* Fallthrough */
5893 case on_failure_jump_loop:
5894 case on_failure_jump:
5895 case succeed_n:
5896 d = str;
5897 continue_failure_jump:
5898 EXTRACT_NUMBER_AND_INCR (mcnt, pat);
5899 p = pat + mcnt;
5900 break;
5902 case no_op:
5903 /* A special frame used for nastyloops. */
5904 goto fail;
5906 default:
5907 abort();
5910 assert (p >= bufp->buffer && p <= pend);
5912 if (d >= string1 && d <= end1)
5913 dend = end_match_1;
5915 else
5916 break; /* Matching at this starting point really fails. */
5917 } /* for (;;) */
5919 if (best_regs_set)
5920 goto restore_best_regs;
5922 FREE_VARIABLES ();
5924 return -1; /* Failure to match. */
5925 } /* re_match_2 */
5927 /* Subroutine definitions for re_match_2. */
5929 /* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
5930 bytes; nonzero otherwise. */
5932 static int
5933 bcmp_translate (s1, s2, len, translate, multibyte)
5934 re_char *s1, *s2;
5935 register int len;
5936 RE_TRANSLATE_TYPE translate;
5937 const int multibyte;
5939 register re_char *p1 = s1, *p2 = s2;
5940 re_char *p1_end = s1 + len;
5941 re_char *p2_end = s2 + len;
5943 /* FIXME: Checking both p1 and p2 presumes that the two strings might have
5944 different lengths, but relying on a single `len' would break this. -sm */
5945 while (p1 < p1_end && p2 < p2_end)
5947 int p1_charlen, p2_charlen;
5948 re_wchar_t p1_ch, p2_ch;
5950 p1_ch = RE_STRING_CHAR_AND_LENGTH (p1, p1_end - p1, p1_charlen);
5951 p2_ch = RE_STRING_CHAR_AND_LENGTH (p2, p2_end - p2, p2_charlen);
5953 if (RE_TRANSLATE (translate, p1_ch)
5954 != RE_TRANSLATE (translate, p2_ch))
5955 return 1;
5957 p1 += p1_charlen, p2 += p2_charlen;
5960 if (p1 != p1_end || p2 != p2_end)
5961 return 1;
5963 return 0;
5966 /* Entry points for GNU code. */
5968 /* re_compile_pattern is the GNU regular expression compiler: it
5969 compiles PATTERN (of length SIZE) and puts the result in BUFP.
5970 Returns 0 if the pattern was valid, otherwise an error string.
5972 Assumes the `allocated' (and perhaps `buffer') and `translate' fields
5973 are set in BUFP on entry.
5975 We call regex_compile to do the actual compilation. */
5977 const char *
5978 re_compile_pattern (pattern, length, bufp)
5979 const char *pattern;
5980 size_t length;
5981 struct re_pattern_buffer *bufp;
5983 reg_errcode_t ret;
5985 /* GNU code is written to assume at least RE_NREGS registers will be set
5986 (and at least one extra will be -1). */
5987 bufp->regs_allocated = REGS_UNALLOCATED;
5989 /* And GNU code determines whether or not to get register information
5990 by passing null for the REGS argument to re_match, etc., not by
5991 setting no_sub. */
5992 bufp->no_sub = 0;
5994 ret = regex_compile ((re_char*) pattern, length, re_syntax_options, bufp);
5996 if (!ret)
5997 return NULL;
5998 return gettext (re_error_msgid[(int) ret]);
6000 WEAK_ALIAS (__re_compile_pattern, re_compile_pattern)
6002 /* Entry points compatible with 4.2 BSD regex library. We don't define
6003 them unless specifically requested. */
6005 #if defined _REGEX_RE_COMP || defined _LIBC
6007 /* BSD has one and only one pattern buffer. */
6008 static struct re_pattern_buffer re_comp_buf;
6010 char *
6011 # ifdef _LIBC
6012 /* Make these definitions weak in libc, so POSIX programs can redefine
6013 these names if they don't use our functions, and still use
6014 regcomp/regexec below without link errors. */
6015 weak_function
6016 # endif
6017 re_comp (s)
6018 const char *s;
6020 reg_errcode_t ret;
6022 if (!s)
6024 if (!re_comp_buf.buffer)
6025 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6026 return (char *) gettext ("No previous regular expression");
6027 return 0;
6030 if (!re_comp_buf.buffer)
6032 re_comp_buf.buffer = (unsigned char *) malloc (200);
6033 if (re_comp_buf.buffer == NULL)
6034 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6035 return (char *) gettext (re_error_msgid[(int) REG_ESPACE]);
6036 re_comp_buf.allocated = 200;
6038 re_comp_buf.fastmap = (char *) malloc (1 << BYTEWIDTH);
6039 if (re_comp_buf.fastmap == NULL)
6040 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6041 return (char *) gettext (re_error_msgid[(int) REG_ESPACE]);
6044 /* Since `re_exec' always passes NULL for the `regs' argument, we
6045 don't need to initialize the pattern buffer fields which affect it. */
6047 ret = regex_compile (s, strlen (s), re_syntax_options, &re_comp_buf);
6049 if (!ret)
6050 return NULL;
6052 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6053 return (char *) gettext (re_error_msgid[(int) ret]);
6058 # ifdef _LIBC
6059 weak_function
6060 # endif
6061 re_exec (s)
6062 const char *s;
6064 const int len = strlen (s);
6065 return
6066 0 <= re_search (&re_comp_buf, s, len, 0, len, (struct re_registers *) 0);
6068 #endif /* _REGEX_RE_COMP */
6070 /* POSIX.2 functions. Don't define these for Emacs. */
6072 #ifndef emacs
6074 /* regcomp takes a regular expression as a string and compiles it.
6076 PREG is a regex_t *. We do not expect any fields to be initialized,
6077 since POSIX says we shouldn't. Thus, we set
6079 `buffer' to the compiled pattern;
6080 `used' to the length of the compiled pattern;
6081 `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
6082 REG_EXTENDED bit in CFLAGS is set; otherwise, to
6083 RE_SYNTAX_POSIX_BASIC;
6084 `fastmap' to an allocated space for the fastmap;
6085 `fastmap_accurate' to zero;
6086 `re_nsub' to the number of subexpressions in PATTERN.
6088 PATTERN is the address of the pattern string.
6090 CFLAGS is a series of bits which affect compilation.
6092 If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
6093 use POSIX basic syntax.
6095 If REG_NEWLINE is set, then . and [^...] don't match newline.
6096 Also, regexec will try a match beginning after every newline.
6098 If REG_ICASE is set, then we considers upper- and lowercase
6099 versions of letters to be equivalent when matching.
6101 If REG_NOSUB is set, then when PREG is passed to regexec, that
6102 routine will report only success or failure, and nothing about the
6103 registers.
6105 It returns 0 if it succeeds, nonzero if it doesn't. (See regex.h for
6106 the return codes and their meanings.) */
6109 regcomp (preg, pattern, cflags)
6110 regex_t *__restrict preg;
6111 const char *__restrict pattern;
6112 int cflags;
6114 reg_errcode_t ret;
6115 reg_syntax_t syntax
6116 = (cflags & REG_EXTENDED) ?
6117 RE_SYNTAX_POSIX_EXTENDED : RE_SYNTAX_POSIX_BASIC;
6119 /* regex_compile will allocate the space for the compiled pattern. */
6120 preg->buffer = 0;
6121 preg->allocated = 0;
6122 preg->used = 0;
6124 /* Try to allocate space for the fastmap. */
6125 preg->fastmap = (char *) malloc (1 << BYTEWIDTH);
6127 if (cflags & REG_ICASE)
6129 unsigned i;
6131 preg->translate
6132 = (RE_TRANSLATE_TYPE) malloc (CHAR_SET_SIZE
6133 * sizeof (*(RE_TRANSLATE_TYPE)0));
6134 if (preg->translate == NULL)
6135 return (int) REG_ESPACE;
6137 /* Map uppercase characters to corresponding lowercase ones. */
6138 for (i = 0; i < CHAR_SET_SIZE; i++)
6139 preg->translate[i] = ISUPPER (i) ? TOLOWER (i) : i;
6141 else
6142 preg->translate = NULL;
6144 /* If REG_NEWLINE is set, newlines are treated differently. */
6145 if (cflags & REG_NEWLINE)
6146 { /* REG_NEWLINE implies neither . nor [^...] match newline. */
6147 syntax &= ~RE_DOT_NEWLINE;
6148 syntax |= RE_HAT_LISTS_NOT_NEWLINE;
6150 else
6151 syntax |= RE_NO_NEWLINE_ANCHOR;
6153 preg->no_sub = !!(cflags & REG_NOSUB);
6155 /* POSIX says a null character in the pattern terminates it, so we
6156 can use strlen here in compiling the pattern. */
6157 ret = regex_compile ((re_char*) pattern, strlen (pattern), syntax, preg);
6159 /* POSIX doesn't distinguish between an unmatched open-group and an
6160 unmatched close-group: both are REG_EPAREN. */
6161 if (ret == REG_ERPAREN)
6162 ret = REG_EPAREN;
6164 if (ret == REG_NOERROR && preg->fastmap)
6165 { /* Compute the fastmap now, since regexec cannot modify the pattern
6166 buffer. */
6167 re_compile_fastmap (preg);
6168 if (preg->can_be_null)
6169 { /* The fastmap can't be used anyway. */
6170 free (preg->fastmap);
6171 preg->fastmap = NULL;
6174 return (int) ret;
6176 WEAK_ALIAS (__regcomp, regcomp)
6179 /* regexec searches for a given pattern, specified by PREG, in the
6180 string STRING.
6182 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
6183 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
6184 least NMATCH elements, and we set them to the offsets of the
6185 corresponding matched substrings.
6187 EFLAGS specifies `execution flags' which affect matching: if
6188 REG_NOTBOL is set, then ^ does not match at the beginning of the
6189 string; if REG_NOTEOL is set, then $ does not match at the end.
6191 We return 0 if we find a match and REG_NOMATCH if not. */
6194 regexec (preg, string, nmatch, pmatch, eflags)
6195 const regex_t *__restrict preg;
6196 const char *__restrict string;
6197 size_t nmatch;
6198 regmatch_t pmatch[__restrict_arr];
6199 int eflags;
6201 int ret;
6202 struct re_registers regs;
6203 regex_t private_preg;
6204 int len = strlen (string);
6205 boolean want_reg_info = !preg->no_sub && nmatch > 0 && pmatch;
6207 private_preg = *preg;
6209 private_preg.not_bol = !!(eflags & REG_NOTBOL);
6210 private_preg.not_eol = !!(eflags & REG_NOTEOL);
6212 /* The user has told us exactly how many registers to return
6213 information about, via `nmatch'. We have to pass that on to the
6214 matching routines. */
6215 private_preg.regs_allocated = REGS_FIXED;
6217 if (want_reg_info)
6219 regs.num_regs = nmatch;
6220 regs.start = TALLOC (nmatch * 2, regoff_t);
6221 if (regs.start == NULL)
6222 return (int) REG_NOMATCH;
6223 regs.end = regs.start + nmatch;
6226 /* Instead of using not_eol to implement REG_NOTEOL, we could simply
6227 pass (&private_preg, string, len + 1, 0, len, ...) pretending the string
6228 was a little bit longer but still only matching the real part.
6229 This works because the `endline' will check for a '\n' and will find a
6230 '\0', correctly deciding that this is not the end of a line.
6231 But it doesn't work out so nicely for REG_NOTBOL, since we don't have
6232 a convenient '\0' there. For all we know, the string could be preceded
6233 by '\n' which would throw things off. */
6235 /* Perform the searching operation. */
6236 ret = re_search (&private_preg, string, len,
6237 /* start: */ 0, /* range: */ len,
6238 want_reg_info ? &regs : (struct re_registers *) 0);
6240 /* Copy the register information to the POSIX structure. */
6241 if (want_reg_info)
6243 if (ret >= 0)
6245 unsigned r;
6247 for (r = 0; r < nmatch; r++)
6249 pmatch[r].rm_so = regs.start[r];
6250 pmatch[r].rm_eo = regs.end[r];
6254 /* If we needed the temporary register info, free the space now. */
6255 free (regs.start);
6258 /* We want zero return to mean success, unlike `re_search'. */
6259 return ret >= 0 ? (int) REG_NOERROR : (int) REG_NOMATCH;
6261 WEAK_ALIAS (__regexec, regexec)
6264 /* Returns a message corresponding to an error code, ERRCODE, returned
6265 from either regcomp or regexec. We don't use PREG here. */
6267 size_t
6268 regerror (errcode, preg, errbuf, errbuf_size)
6269 int errcode;
6270 const regex_t *preg;
6271 char *errbuf;
6272 size_t errbuf_size;
6274 const char *msg;
6275 size_t msg_size;
6277 if (errcode < 0
6278 || errcode >= (sizeof (re_error_msgid) / sizeof (re_error_msgid[0])))
6279 /* Only error codes returned by the rest of the code should be passed
6280 to this routine. If we are given anything else, or if other regex
6281 code generates an invalid error code, then the program has a bug.
6282 Dump core so we can fix it. */
6283 abort ();
6285 msg = gettext (re_error_msgid[errcode]);
6287 msg_size = strlen (msg) + 1; /* Includes the null. */
6289 if (errbuf_size != 0)
6291 if (msg_size > errbuf_size)
6293 strncpy (errbuf, msg, errbuf_size - 1);
6294 errbuf[errbuf_size - 1] = 0;
6296 else
6297 strcpy (errbuf, msg);
6300 return msg_size;
6302 WEAK_ALIAS (__regerror, regerror)
6305 /* Free dynamically allocated space used by PREG. */
6307 void
6308 regfree (preg)
6309 regex_t *preg;
6311 if (preg->buffer != NULL)
6312 free (preg->buffer);
6313 preg->buffer = NULL;
6315 preg->allocated = 0;
6316 preg->used = 0;
6318 if (preg->fastmap != NULL)
6319 free (preg->fastmap);
6320 preg->fastmap = NULL;
6321 preg->fastmap_accurate = 0;
6323 if (preg->translate != NULL)
6324 free (preg->translate);
6325 preg->translate = NULL;
6327 WEAK_ALIAS (__regfree, regfree)
6329 #endif /* not emacs */