* todo-mode.el: Offer to convert legacy file. Update commentary.
[emacs.git] / src / regex.c
blob79fb28ba12a6a7fb11a64e4842d773e6c7bf36ca
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) 1993-2013 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 3, 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, see <http://www.gnu.org/licenses/>. */
20 /* TODO:
21 - structure the opcode space into opcode+flag.
22 - merge with glibc's regex.[ch].
23 - replace (succeed_n + jump_n + set_number_at) with something that doesn't
24 need to modify the compiled regexp so that re_match can be reentrant.
25 - get rid of on_failure_jump_smart by doing the optimization in re_comp
26 rather than at run-time, so that re_match can be reentrant.
29 /* AIX requires this to be the first thing in the file. */
30 #if defined _AIX && !defined REGEX_MALLOC
31 #pragma alloca
32 #endif
34 /* Ignore some GCC warnings for now. This section should go away
35 once the Emacs and Gnulib regex code is merged. */
36 #if 4 < __GNUC__ + (5 <= __GNUC_MINOR__) || defined __clang__
37 # pragma GCC diagnostic ignored "-Wstrict-overflow"
38 # ifndef emacs
39 # pragma GCC diagnostic ignored "-Wunused-function"
40 # pragma GCC diagnostic ignored "-Wunused-macros"
41 # pragma GCC diagnostic ignored "-Wunused-result"
42 # pragma GCC diagnostic ignored "-Wunused-variable"
43 # endif
44 #endif
46 #if 4 < __GNUC__ + (5 <= __GNUC_MINOR__) && ! defined __clang__
47 # pragma GCC diagnostic ignored "-Wunused-but-set-variable"
48 #endif
50 #include <config.h>
52 #include <stddef.h>
54 #ifdef emacs
55 /* We need this for `regex.h', and perhaps for the Emacs include files. */
56 # include <sys/types.h>
57 #endif
59 /* Whether to use ISO C Amendment 1 wide char functions.
60 Those should not be used for Emacs since it uses its own. */
61 #if defined _LIBC
62 #define WIDE_CHAR_SUPPORT 1
63 #else
64 #define WIDE_CHAR_SUPPORT \
65 (HAVE_WCTYPE_H && HAVE_WCHAR_H && HAVE_BTOWC && !emacs)
66 #endif
68 /* For platform which support the ISO C amendment 1 functionality we
69 support user defined character classes. */
70 #if WIDE_CHAR_SUPPORT
71 /* Solaris 2.5 has a bug: <wchar.h> must be included before <wctype.h>. */
72 # include <wchar.h>
73 # include <wctype.h>
74 #endif
76 #ifdef _LIBC
77 /* We have to keep the namespace clean. */
78 # define regfree(preg) __regfree (preg)
79 # define regexec(pr, st, nm, pm, ef) __regexec (pr, st, nm, pm, ef)
80 # define regcomp(preg, pattern, cflags) __regcomp (preg, pattern, cflags)
81 # define regerror(err_code, preg, errbuf, errbuf_size) \
82 __regerror (err_code, preg, errbuf, errbuf_size)
83 # define re_set_registers(bu, re, nu, st, en) \
84 __re_set_registers (bu, re, nu, st, en)
85 # define re_match_2(bufp, string1, size1, string2, size2, pos, regs, stop) \
86 __re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
87 # define re_match(bufp, string, size, pos, regs) \
88 __re_match (bufp, string, size, pos, regs)
89 # define re_search(bufp, string, size, startpos, range, regs) \
90 __re_search (bufp, string, size, startpos, range, regs)
91 # define re_compile_pattern(pattern, length, bufp) \
92 __re_compile_pattern (pattern, length, bufp)
93 # define re_set_syntax(syntax) __re_set_syntax (syntax)
94 # define re_search_2(bufp, st1, s1, st2, s2, startpos, range, regs, stop) \
95 __re_search_2 (bufp, st1, s1, st2, s2, startpos, range, regs, stop)
96 # define re_compile_fastmap(bufp) __re_compile_fastmap (bufp)
98 /* Make sure we call libc's function even if the user overrides them. */
99 # define btowc __btowc
100 # define iswctype __iswctype
101 # define wctype __wctype
103 # define WEAK_ALIAS(a,b) weak_alias (a, b)
105 /* We are also using some library internals. */
106 # include <locale/localeinfo.h>
107 # include <locale/elem-hash.h>
108 # include <langinfo.h>
109 #else
110 # define WEAK_ALIAS(a,b)
111 #endif
113 /* This is for other GNU distributions with internationalized messages. */
114 #if HAVE_LIBINTL_H || defined _LIBC
115 # include <libintl.h>
116 #else
117 # define gettext(msgid) (msgid)
118 #endif
120 #ifndef gettext_noop
121 /* This define is so xgettext can find the internationalizable
122 strings. */
123 # define gettext_noop(String) String
124 #endif
126 /* The `emacs' switch turns on certain matching commands
127 that make sense only in Emacs. */
128 #ifdef emacs
130 # include "lisp.h"
131 # include "character.h"
132 # include "buffer.h"
134 /* Make syntax table lookup grant data in gl_state. */
135 # define SYNTAX_ENTRY_VIA_PROPERTY
137 # include "syntax.h"
138 # include "category.h"
140 # ifdef malloc
141 # undef malloc
142 # endif
143 # define malloc xmalloc
144 # ifdef realloc
145 # undef realloc
146 # endif
147 # define realloc xrealloc
148 # ifdef free
149 # undef free
150 # endif
151 # define free xfree
153 /* Converts the pointer to the char to BEG-based offset from the start. */
154 # define PTR_TO_OFFSET(d) POS_AS_IN_BUFFER (POINTER_TO_OFFSET (d))
155 # define POS_AS_IN_BUFFER(p) ((p) + (NILP (re_match_object) || BUFFERP (re_match_object)))
157 # define RE_MULTIBYTE_P(bufp) ((bufp)->multibyte)
158 # define RE_TARGET_MULTIBYTE_P(bufp) ((bufp)->target_multibyte)
159 # define RE_STRING_CHAR(p, multibyte) \
160 (multibyte ? (STRING_CHAR (p)) : (*(p)))
161 # define RE_STRING_CHAR_AND_LENGTH(p, len, multibyte) \
162 (multibyte ? (STRING_CHAR_AND_LENGTH (p, len)) : ((len) = 1, *(p)))
164 # define RE_CHAR_TO_MULTIBYTE(c) UNIBYTE_TO_CHAR (c)
166 # define RE_CHAR_TO_UNIBYTE(c) CHAR_TO_BYTE_SAFE (c)
168 /* Set C a (possibly converted to multibyte) character before P. P
169 points into a string which is the virtual concatenation of STR1
170 (which ends at END1) or STR2 (which ends at END2). */
171 # define GET_CHAR_BEFORE_2(c, p, str1, end1, str2, end2) \
172 do { \
173 if (target_multibyte) \
175 re_char *dtemp = (p) == (str2) ? (end1) : (p); \
176 re_char *dlimit = ((p) > (str2) && (p) <= (end2)) ? (str2) : (str1); \
177 while (dtemp-- > dlimit && !CHAR_HEAD_P (*dtemp)); \
178 c = STRING_CHAR (dtemp); \
180 else \
182 (c = ((p) == (str2) ? (end1) : (p))[-1]); \
183 (c) = RE_CHAR_TO_MULTIBYTE (c); \
185 } while (0)
187 /* Set C a (possibly converted to multibyte) character at P, and set
188 LEN to the byte length of that character. */
189 # define GET_CHAR_AFTER(c, p, len) \
190 do { \
191 if (target_multibyte) \
192 (c) = STRING_CHAR_AND_LENGTH (p, len); \
193 else \
195 (c) = *p; \
196 len = 1; \
197 (c) = RE_CHAR_TO_MULTIBYTE (c); \
199 } while (0)
201 #else /* not emacs */
203 /* If we are not linking with Emacs proper,
204 we can't use the relocating allocator
205 even if config.h says that we can. */
206 # undef REL_ALLOC
208 # include <unistd.h>
210 /* When used in Emacs's lib-src, we need xmalloc and xrealloc. */
212 static void *
213 xmalloc (size_t size)
215 void *val = malloc (size);
216 if (!val && size)
218 write (2, "virtual memory exhausted\n", 25);
219 exit (1);
221 return val;
224 static void *
225 xrealloc (void *block, size_t size)
227 void *val;
228 /* We must call malloc explicitly when BLOCK is 0, since some
229 reallocs don't do this. */
230 if (! block)
231 val = malloc (size);
232 else
233 val = realloc (block, size);
234 if (!val && size)
236 write (2, "virtual memory exhausted\n", 25);
237 exit (1);
239 return val;
242 # ifdef malloc
243 # undef malloc
244 # endif
245 # define malloc xmalloc
246 # ifdef realloc
247 # undef realloc
248 # endif
249 # define realloc xrealloc
251 # include <stdbool.h>
252 # include <string.h>
254 /* Define the syntax stuff for \<, \>, etc. */
256 /* Sword must be nonzero for the wordchar pattern commands in re_match_2. */
257 enum syntaxcode { Swhitespace = 0, Sword = 1, Ssymbol = 2 };
259 /* Dummy macros for non-Emacs environments. */
260 # define CHAR_CHARSET(c) 0
261 # define CHARSET_LEADING_CODE_BASE(c) 0
262 # define MAX_MULTIBYTE_LENGTH 1
263 # define RE_MULTIBYTE_P(x) 0
264 # define RE_TARGET_MULTIBYTE_P(x) 0
265 # define WORD_BOUNDARY_P(c1, c2) (0)
266 # define CHAR_HEAD_P(p) (1)
267 # define SINGLE_BYTE_CHAR_P(c) (1)
268 # define SAME_CHARSET_P(c1, c2) (1)
269 # define BYTES_BY_CHAR_HEAD(p) (1)
270 # define PREV_CHAR_BOUNDARY(p, limit) ((p)--)
271 # define STRING_CHAR(p) (*(p))
272 # define RE_STRING_CHAR(p, multibyte) STRING_CHAR (p)
273 # define CHAR_STRING(c, s) (*(s) = (c), 1)
274 # define STRING_CHAR_AND_LENGTH(p, actual_len) ((actual_len) = 1, *(p))
275 # define RE_STRING_CHAR_AND_LENGTH(p, len, multibyte) STRING_CHAR_AND_LENGTH (p, len)
276 # define RE_CHAR_TO_MULTIBYTE(c) (c)
277 # define RE_CHAR_TO_UNIBYTE(c) (c)
278 # define GET_CHAR_BEFORE_2(c, p, str1, end1, str2, end2) \
279 (c = ((p) == (str2) ? *((end1) - 1) : *((p) - 1)))
280 # define GET_CHAR_AFTER(c, p, len) \
281 (c = *p, len = 1)
282 # define MAKE_CHAR(charset, c1, c2) (c1)
283 # define BYTE8_TO_CHAR(c) (c)
284 # define CHAR_BYTE8_P(c) (0)
285 # define CHAR_LEADING_CODE(c) (c)
287 #endif /* not emacs */
289 #ifndef RE_TRANSLATE
290 # define RE_TRANSLATE(TBL, C) ((unsigned char)(TBL)[C])
291 # define RE_TRANSLATE_P(TBL) (TBL)
292 #endif
294 /* Get the interface, including the syntax bits. */
295 #include "regex.h"
297 /* isalpha etc. are used for the character classes. */
298 #include <ctype.h>
300 #ifdef emacs
302 /* 1 if C is an ASCII character. */
303 # define IS_REAL_ASCII(c) ((c) < 0200)
305 /* 1 if C is a unibyte character. */
306 # define ISUNIBYTE(c) (SINGLE_BYTE_CHAR_P ((c)))
308 /* The Emacs definitions should not be directly affected by locales. */
310 /* In Emacs, these are only used for single-byte characters. */
311 # define ISDIGIT(c) ((c) >= '0' && (c) <= '9')
312 # define ISCNTRL(c) ((c) < ' ')
313 # define ISXDIGIT(c) (((c) >= '0' && (c) <= '9') \
314 || ((c) >= 'a' && (c) <= 'f') \
315 || ((c) >= 'A' && (c) <= 'F'))
317 /* This is only used for single-byte characters. */
318 # define ISBLANK(c) ((c) == ' ' || (c) == '\t')
320 /* The rest must handle multibyte characters. */
322 # define ISGRAPH(c) (SINGLE_BYTE_CHAR_P (c) \
323 ? (c) > ' ' && !((c) >= 0177 && (c) <= 0237) \
324 : 1)
326 # define ISPRINT(c) (SINGLE_BYTE_CHAR_P (c) \
327 ? (c) >= ' ' && !((c) >= 0177 && (c) <= 0237) \
328 : 1)
330 # define ISALNUM(c) (IS_REAL_ASCII (c) \
331 ? (((c) >= 'a' && (c) <= 'z') \
332 || ((c) >= 'A' && (c) <= 'Z') \
333 || ((c) >= '0' && (c) <= '9')) \
334 : SYNTAX (c) == Sword)
336 # define ISALPHA(c) (IS_REAL_ASCII (c) \
337 ? (((c) >= 'a' && (c) <= 'z') \
338 || ((c) >= 'A' && (c) <= 'Z')) \
339 : SYNTAX (c) == Sword)
341 # define ISLOWER(c) lowercasep (c)
343 # define ISPUNCT(c) (IS_REAL_ASCII (c) \
344 ? ((c) > ' ' && (c) < 0177 \
345 && !(((c) >= 'a' && (c) <= 'z') \
346 || ((c) >= 'A' && (c) <= 'Z') \
347 || ((c) >= '0' && (c) <= '9'))) \
348 : SYNTAX (c) != Sword)
350 # define ISSPACE(c) (SYNTAX (c) == Swhitespace)
352 # define ISUPPER(c) uppercasep (c)
354 # define ISWORD(c) (SYNTAX (c) == Sword)
356 #else /* not emacs */
358 /* 1 if C is an ASCII character. */
359 # define IS_REAL_ASCII(c) ((c) < 0200)
361 /* This distinction is not meaningful, except in Emacs. */
362 # define ISUNIBYTE(c) 1
364 # ifdef isblank
365 # define ISBLANK(c) isblank (c)
366 # else
367 # define ISBLANK(c) ((c) == ' ' || (c) == '\t')
368 # endif
369 # ifdef isgraph
370 # define ISGRAPH(c) isgraph (c)
371 # else
372 # define ISGRAPH(c) (isprint (c) && !isspace (c))
373 # endif
375 /* Solaris defines ISPRINT so we must undefine it first. */
376 # undef ISPRINT
377 # define ISPRINT(c) isprint (c)
378 # define ISDIGIT(c) isdigit (c)
379 # define ISALNUM(c) isalnum (c)
380 # define ISALPHA(c) isalpha (c)
381 # define ISCNTRL(c) iscntrl (c)
382 # define ISLOWER(c) islower (c)
383 # define ISPUNCT(c) ispunct (c)
384 # define ISSPACE(c) isspace (c)
385 # define ISUPPER(c) isupper (c)
386 # define ISXDIGIT(c) isxdigit (c)
388 # define ISWORD(c) ISALPHA (c)
390 # ifdef _tolower
391 # define TOLOWER(c) _tolower (c)
392 # else
393 # define TOLOWER(c) tolower (c)
394 # endif
396 /* How many characters in the character set. */
397 # define CHAR_SET_SIZE 256
399 # ifdef SYNTAX_TABLE
401 extern char *re_syntax_table;
403 # else /* not SYNTAX_TABLE */
405 static char re_syntax_table[CHAR_SET_SIZE];
407 static void
408 init_syntax_once (void)
410 register int c;
411 static int done = 0;
413 if (done)
414 return;
416 memset (re_syntax_table, 0, sizeof re_syntax_table);
418 for (c = 0; c < CHAR_SET_SIZE; ++c)
419 if (ISALNUM (c))
420 re_syntax_table[c] = Sword;
422 re_syntax_table['_'] = Ssymbol;
424 done = 1;
427 # endif /* not SYNTAX_TABLE */
429 # define SYNTAX(c) re_syntax_table[(c)]
431 #endif /* not emacs */
433 #define SIGN_EXTEND_CHAR(c) ((signed char) (c))
435 /* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we
436 use `alloca' instead of `malloc'. This is because using malloc in
437 re_search* or re_match* could cause memory leaks when C-g is used in
438 Emacs; also, malloc is slower and causes storage fragmentation. On
439 the other hand, malloc is more portable, and easier to debug.
441 Because we sometimes use alloca, some routines have to be macros,
442 not functions -- `alloca'-allocated space disappears at the end of the
443 function it is called in. */
445 #ifdef REGEX_MALLOC
447 # define REGEX_ALLOCATE malloc
448 # define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
449 # define REGEX_FREE free
451 #else /* not REGEX_MALLOC */
453 /* Emacs already defines alloca, sometimes. */
454 # ifndef alloca
456 /* Make alloca work the best possible way. */
457 # ifdef __GNUC__
458 # define alloca __builtin_alloca
459 # else /* not __GNUC__ */
460 # ifdef HAVE_ALLOCA_H
461 # include <alloca.h>
462 # endif /* HAVE_ALLOCA_H */
463 # endif /* not __GNUC__ */
465 # endif /* not alloca */
467 # define REGEX_ALLOCATE alloca
469 /* Assumes a `char *destination' variable. */
470 # define REGEX_REALLOCATE(source, osize, nsize) \
471 (destination = (char *) alloca (nsize), \
472 memcpy (destination, source, osize))
474 /* No need to do anything to free, after alloca. */
475 # define REGEX_FREE(arg) ((void)0) /* Do nothing! But inhibit gcc warning. */
477 #endif /* not REGEX_MALLOC */
479 /* Define how to allocate the failure stack. */
481 #if defined REL_ALLOC && defined REGEX_MALLOC
483 # define REGEX_ALLOCATE_STACK(size) \
484 r_alloc (&failure_stack_ptr, (size))
485 # define REGEX_REALLOCATE_STACK(source, osize, nsize) \
486 r_re_alloc (&failure_stack_ptr, (nsize))
487 # define REGEX_FREE_STACK(ptr) \
488 r_alloc_free (&failure_stack_ptr)
490 #else /* not using relocating allocator */
492 # ifdef REGEX_MALLOC
494 # define REGEX_ALLOCATE_STACK malloc
495 # define REGEX_REALLOCATE_STACK(source, osize, nsize) realloc (source, nsize)
496 # define REGEX_FREE_STACK free
498 # else /* not REGEX_MALLOC */
500 # define REGEX_ALLOCATE_STACK alloca
502 # define REGEX_REALLOCATE_STACK(source, osize, nsize) \
503 REGEX_REALLOCATE (source, osize, nsize)
504 /* No need to explicitly free anything. */
505 # define REGEX_FREE_STACK(arg) ((void)0)
507 # endif /* not REGEX_MALLOC */
508 #endif /* not using relocating allocator */
511 /* True if `size1' is non-NULL and PTR is pointing anywhere inside
512 `string1' or just past its end. This works if PTR is NULL, which is
513 a good thing. */
514 #define FIRST_STRING_P(ptr) \
515 (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
517 /* (Re)Allocate N items of type T using malloc, or fail. */
518 #define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
519 #define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
520 #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
522 #define BYTEWIDTH 8 /* In bits. */
524 #define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
526 #undef MAX
527 #undef MIN
528 #define MAX(a, b) ((a) > (b) ? (a) : (b))
529 #define MIN(a, b) ((a) < (b) ? (a) : (b))
531 /* Type of source-pattern and string chars. */
532 #ifdef _MSC_VER
533 typedef unsigned char re_char;
534 #else
535 typedef const unsigned char re_char;
536 #endif
538 typedef char boolean;
540 static regoff_t re_match_2_internal (struct re_pattern_buffer *bufp,
541 re_char *string1, size_t size1,
542 re_char *string2, size_t size2,
543 ssize_t pos,
544 struct re_registers *regs,
545 ssize_t stop);
547 /* These are the command codes that appear in compiled regular
548 expressions. Some opcodes are followed by argument bytes. A
549 command code can specify any interpretation whatsoever for its
550 arguments. Zero bytes may appear in the compiled regular expression. */
552 typedef enum
554 no_op = 0,
556 /* Succeed right away--no more backtracking. */
557 succeed,
559 /* Followed by one byte giving n, then by n literal bytes. */
560 exactn,
562 /* Matches any (more or less) character. */
563 anychar,
565 /* Matches any one char belonging to specified set. First
566 following byte is number of bitmap bytes. Then come bytes
567 for a bitmap saying which chars are in. Bits in each byte
568 are ordered low-bit-first. A character is in the set if its
569 bit is 1. A character too large to have a bit in the map is
570 automatically not in the set.
572 If the length byte has the 0x80 bit set, then that stuff
573 is followed by a range table:
574 2 bytes of flags for character sets (low 8 bits, high 8 bits)
575 See RANGE_TABLE_WORK_BITS below.
576 2 bytes, the number of pairs that follow (upto 32767)
577 pairs, each 2 multibyte characters,
578 each multibyte character represented as 3 bytes. */
579 charset,
581 /* Same parameters as charset, but match any character that is
582 not one of those specified. */
583 charset_not,
585 /* Start remembering the text that is matched, for storing in a
586 register. Followed by one byte with the register number, in
587 the range 0 to one less than the pattern buffer's re_nsub
588 field. */
589 start_memory,
591 /* Stop remembering the text that is matched and store it in a
592 memory register. Followed by one byte with the register
593 number, in the range 0 to one less than `re_nsub' in the
594 pattern buffer. */
595 stop_memory,
597 /* Match a duplicate of something remembered. Followed by one
598 byte containing the register number. */
599 duplicate,
601 /* Fail unless at beginning of line. */
602 begline,
604 /* Fail unless at end of line. */
605 endline,
607 /* Succeeds if at beginning of buffer (if emacs) or at beginning
608 of string to be matched (if not). */
609 begbuf,
611 /* Analogously, for end of buffer/string. */
612 endbuf,
614 /* Followed by two byte relative address to which to jump. */
615 jump,
617 /* Followed by two-byte relative address of place to resume at
618 in case of failure. */
619 on_failure_jump,
621 /* Like on_failure_jump, but pushes a placeholder instead of the
622 current string position when executed. */
623 on_failure_keep_string_jump,
625 /* Just like `on_failure_jump', except that it checks that we
626 don't get stuck in an infinite loop (matching an empty string
627 indefinitely). */
628 on_failure_jump_loop,
630 /* Just like `on_failure_jump_loop', except that it checks for
631 a different kind of loop (the kind that shows up with non-greedy
632 operators). This operation has to be immediately preceded
633 by a `no_op'. */
634 on_failure_jump_nastyloop,
636 /* A smart `on_failure_jump' used for greedy * and + operators.
637 It analyzes the loop before which it is put and if the
638 loop does not require backtracking, it changes itself to
639 `on_failure_keep_string_jump' and short-circuits the loop,
640 else it just defaults to changing itself into `on_failure_jump'.
641 It assumes that it is pointing to just past a `jump'. */
642 on_failure_jump_smart,
644 /* Followed by two-byte relative address and two-byte number n.
645 After matching N times, jump to the address upon failure.
646 Does not work if N starts at 0: use on_failure_jump_loop
647 instead. */
648 succeed_n,
650 /* Followed by two-byte relative address, and two-byte number n.
651 Jump to the address N times, then fail. */
652 jump_n,
654 /* Set the following two-byte relative address to the
655 subsequent two-byte number. The address *includes* the two
656 bytes of number. */
657 set_number_at,
659 wordbeg, /* Succeeds if at word beginning. */
660 wordend, /* Succeeds if at word end. */
662 wordbound, /* Succeeds if at a word boundary. */
663 notwordbound, /* Succeeds if not at a word boundary. */
665 symbeg, /* Succeeds if at symbol beginning. */
666 symend, /* Succeeds if at symbol end. */
668 /* Matches any character whose syntax is specified. Followed by
669 a byte which contains a syntax code, e.g., Sword. */
670 syntaxspec,
672 /* Matches any character whose syntax is not that specified. */
673 notsyntaxspec
675 #ifdef emacs
676 ,before_dot, /* Succeeds if before point. */
677 at_dot, /* Succeeds if at point. */
678 after_dot, /* Succeeds if after point. */
680 /* Matches any character whose category-set contains the specified
681 category. The operator is followed by a byte which contains a
682 category code (mnemonic ASCII character). */
683 categoryspec,
685 /* Matches any character whose category-set does not contain the
686 specified category. The operator is followed by a byte which
687 contains the category code (mnemonic ASCII character). */
688 notcategoryspec
689 #endif /* emacs */
690 } re_opcode_t;
692 /* Common operations on the compiled pattern. */
694 /* Store NUMBER in two contiguous bytes starting at DESTINATION. */
696 #define STORE_NUMBER(destination, number) \
697 do { \
698 (destination)[0] = (number) & 0377; \
699 (destination)[1] = (number) >> 8; \
700 } while (0)
702 /* Same as STORE_NUMBER, except increment DESTINATION to
703 the byte after where the number is stored. Therefore, DESTINATION
704 must be an lvalue. */
706 #define STORE_NUMBER_AND_INCR(destination, number) \
707 do { \
708 STORE_NUMBER (destination, number); \
709 (destination) += 2; \
710 } while (0)
712 /* Put into DESTINATION a number stored in two contiguous bytes starting
713 at SOURCE. */
715 #define EXTRACT_NUMBER(destination, source) \
716 ((destination) = extract_number (source))
718 static int
719 extract_number (re_char *source)
721 return (SIGN_EXTEND_CHAR (source[1]) << 8) + source[0];
724 /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
725 SOURCE must be an lvalue. */
727 #define EXTRACT_NUMBER_AND_INCR(destination, source) \
728 ((destination) = extract_number_and_incr (&source))
730 static int
731 extract_number_and_incr (re_char **source)
733 int num = extract_number (*source);
734 *source += 2;
735 return num;
738 /* Store a multibyte character in three contiguous bytes starting
739 DESTINATION, and increment DESTINATION to the byte after where the
740 character is stored. Therefore, DESTINATION must be an lvalue. */
742 #define STORE_CHARACTER_AND_INCR(destination, character) \
743 do { \
744 (destination)[0] = (character) & 0377; \
745 (destination)[1] = ((character) >> 8) & 0377; \
746 (destination)[2] = (character) >> 16; \
747 (destination) += 3; \
748 } while (0)
750 /* Put into DESTINATION a character stored in three contiguous bytes
751 starting at SOURCE. */
753 #define EXTRACT_CHARACTER(destination, source) \
754 do { \
755 (destination) = ((source)[0] \
756 | ((source)[1] << 8) \
757 | ((source)[2] << 16)); \
758 } while (0)
761 /* Macros for charset. */
763 /* Size of bitmap of charset P in bytes. P is a start of charset,
764 i.e. *P is (re_opcode_t) charset or (re_opcode_t) charset_not. */
765 #define CHARSET_BITMAP_SIZE(p) ((p)[1] & 0x7F)
767 /* Nonzero if charset P has range table. */
768 #define CHARSET_RANGE_TABLE_EXISTS_P(p) ((p)[1] & 0x80)
770 /* Return the address of range table of charset P. But not the start
771 of table itself, but the before where the number of ranges is
772 stored. `2 +' means to skip re_opcode_t and size of bitmap,
773 and the 2 bytes of flags at the start of the range table. */
774 #define CHARSET_RANGE_TABLE(p) (&(p)[4 + CHARSET_BITMAP_SIZE (p)])
776 /* Extract the bit flags that start a range table. */
777 #define CHARSET_RANGE_TABLE_BITS(p) \
778 ((p)[2 + CHARSET_BITMAP_SIZE (p)] \
779 + (p)[3 + CHARSET_BITMAP_SIZE (p)] * 0x100)
781 /* Return the address of end of RANGE_TABLE. COUNT is number of
782 ranges (which is a pair of (start, end)) in the RANGE_TABLE. `* 2'
783 is start of range and end of range. `* 3' is size of each start
784 and end. */
785 #define CHARSET_RANGE_TABLE_END(range_table, count) \
786 ((range_table) + (count) * 2 * 3)
788 /* Test if C is in RANGE_TABLE. A flag NOT is negated if C is in.
789 COUNT is number of ranges in RANGE_TABLE. */
790 #define CHARSET_LOOKUP_RANGE_TABLE_RAW(not, c, range_table, count) \
791 do \
793 re_wchar_t range_start, range_end; \
794 re_char *rtp; \
795 re_char *range_table_end \
796 = CHARSET_RANGE_TABLE_END ((range_table), (count)); \
798 for (rtp = (range_table); rtp < range_table_end; rtp += 2 * 3) \
800 EXTRACT_CHARACTER (range_start, rtp); \
801 EXTRACT_CHARACTER (range_end, rtp + 3); \
803 if (range_start <= (c) && (c) <= range_end) \
805 (not) = !(not); \
806 break; \
810 while (0)
812 /* Test if C is in range table of CHARSET. The flag NOT is negated if
813 C is listed in it. */
814 #define CHARSET_LOOKUP_RANGE_TABLE(not, c, charset) \
815 do \
817 /* Number of ranges in range table. */ \
818 int count; \
819 re_char *range_table = CHARSET_RANGE_TABLE (charset); \
821 EXTRACT_NUMBER_AND_INCR (count, range_table); \
822 CHARSET_LOOKUP_RANGE_TABLE_RAW ((not), (c), range_table, count); \
824 while (0)
826 /* If DEBUG is defined, Regex prints many voluminous messages about what
827 it is doing (if the variable `debug' is nonzero). If linked with the
828 main program in `iregex.c', you can enter patterns and strings
829 interactively. And if linked with the main program in `main.c' and
830 the other test files, you can run the already-written tests. */
832 #ifdef DEBUG
834 /* We use standard I/O for debugging. */
835 # include <stdio.h>
837 /* It is useful to test things that ``must'' be true when debugging. */
838 # include <assert.h>
840 static int debug = -100000;
842 # define DEBUG_STATEMENT(e) e
843 # define DEBUG_PRINT(...) if (debug > 0) printf (__VA_ARGS__)
844 # define DEBUG_COMPILES_ARGUMENTS
845 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) \
846 if (debug > 0) print_partial_compiled_pattern (s, e)
847 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) \
848 if (debug > 0) print_double_string (w, s1, sz1, s2, sz2)
851 /* Print the fastmap in human-readable form. */
853 static void
854 print_fastmap (char *fastmap)
856 unsigned was_a_range = 0;
857 unsigned i = 0;
859 while (i < (1 << BYTEWIDTH))
861 if (fastmap[i++])
863 was_a_range = 0;
864 putchar (i - 1);
865 while (i < (1 << BYTEWIDTH) && fastmap[i])
867 was_a_range = 1;
868 i++;
870 if (was_a_range)
872 printf ("-");
873 putchar (i - 1);
877 putchar ('\n');
881 /* Print a compiled pattern string in human-readable form, starting at
882 the START pointer into it and ending just before the pointer END. */
884 static void
885 print_partial_compiled_pattern (re_char *start, re_char *end)
887 int mcnt, mcnt2;
888 re_char *p = start;
889 re_char *pend = end;
891 if (start == NULL)
893 fprintf (stderr, "(null)\n");
894 return;
897 /* Loop over pattern commands. */
898 while (p < pend)
900 fprintf (stderr, "%td:\t", p - start);
902 switch ((re_opcode_t) *p++)
904 case no_op:
905 fprintf (stderr, "/no_op");
906 break;
908 case succeed:
909 fprintf (stderr, "/succeed");
910 break;
912 case exactn:
913 mcnt = *p++;
914 fprintf (stderr, "/exactn/%d", mcnt);
917 fprintf (stderr, "/%c", *p++);
919 while (--mcnt);
920 break;
922 case start_memory:
923 fprintf (stderr, "/start_memory/%d", *p++);
924 break;
926 case stop_memory:
927 fprintf (stderr, "/stop_memory/%d", *p++);
928 break;
930 case duplicate:
931 fprintf (stderr, "/duplicate/%d", *p++);
932 break;
934 case anychar:
935 fprintf (stderr, "/anychar");
936 break;
938 case charset:
939 case charset_not:
941 register int c, last = -100;
942 register int in_range = 0;
943 int length = CHARSET_BITMAP_SIZE (p - 1);
944 int has_range_table = CHARSET_RANGE_TABLE_EXISTS_P (p - 1);
946 fprintf (stderr, "/charset [%s",
947 (re_opcode_t) *(p - 1) == charset_not ? "^" : "");
949 if (p + *p >= pend)
950 fprintf (stderr, " !extends past end of pattern! ");
952 for (c = 0; c < 256; c++)
953 if (c / 8 < length
954 && (p[1 + (c/8)] & (1 << (c % 8))))
956 /* Are we starting a range? */
957 if (last + 1 == c && ! in_range)
959 fprintf (stderr, "-");
960 in_range = 1;
962 /* Have we broken a range? */
963 else if (last + 1 != c && in_range)
965 fprintf (stderr, "%c", last);
966 in_range = 0;
969 if (! in_range)
970 fprintf (stderr, "%c", c);
972 last = c;
975 if (in_range)
976 fprintf (stderr, "%c", last);
978 fprintf (stderr, "]");
980 p += 1 + length;
982 if (has_range_table)
984 int count;
985 fprintf (stderr, "has-range-table");
987 /* ??? Should print the range table; for now, just skip it. */
988 p += 2; /* skip range table bits */
989 EXTRACT_NUMBER_AND_INCR (count, p);
990 p = CHARSET_RANGE_TABLE_END (p, count);
993 break;
995 case begline:
996 fprintf (stderr, "/begline");
997 break;
999 case endline:
1000 fprintf (stderr, "/endline");
1001 break;
1003 case on_failure_jump:
1004 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1005 fprintf (stderr, "/on_failure_jump to %td", p + mcnt - start);
1006 break;
1008 case on_failure_keep_string_jump:
1009 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1010 fprintf (stderr, "/on_failure_keep_string_jump to %td",
1011 p + mcnt - start);
1012 break;
1014 case on_failure_jump_nastyloop:
1015 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1016 fprintf (stderr, "/on_failure_jump_nastyloop to %td",
1017 p + mcnt - start);
1018 break;
1020 case on_failure_jump_loop:
1021 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1022 fprintf (stderr, "/on_failure_jump_loop to %td",
1023 p + mcnt - start);
1024 break;
1026 case on_failure_jump_smart:
1027 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1028 fprintf (stderr, "/on_failure_jump_smart to %td",
1029 p + mcnt - start);
1030 break;
1032 case jump:
1033 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1034 fprintf (stderr, "/jump to %td", p + mcnt - start);
1035 break;
1037 case succeed_n:
1038 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1039 EXTRACT_NUMBER_AND_INCR (mcnt2, p);
1040 fprintf (stderr, "/succeed_n to %td, %d times",
1041 p - 2 + mcnt - start, mcnt2);
1042 break;
1044 case jump_n:
1045 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1046 EXTRACT_NUMBER_AND_INCR (mcnt2, p);
1047 fprintf (stderr, "/jump_n to %td, %d times",
1048 p - 2 + mcnt - start, mcnt2);
1049 break;
1051 case set_number_at:
1052 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1053 EXTRACT_NUMBER_AND_INCR (mcnt2, p);
1054 fprintf (stderr, "/set_number_at location %td to %d",
1055 p - 2 + mcnt - start, mcnt2);
1056 break;
1058 case wordbound:
1059 fprintf (stderr, "/wordbound");
1060 break;
1062 case notwordbound:
1063 fprintf (stderr, "/notwordbound");
1064 break;
1066 case wordbeg:
1067 fprintf (stderr, "/wordbeg");
1068 break;
1070 case wordend:
1071 fprintf (stderr, "/wordend");
1072 break;
1074 case symbeg:
1075 fprintf (stderr, "/symbeg");
1076 break;
1078 case symend:
1079 fprintf (stderr, "/symend");
1080 break;
1082 case syntaxspec:
1083 fprintf (stderr, "/syntaxspec");
1084 mcnt = *p++;
1085 fprintf (stderr, "/%d", mcnt);
1086 break;
1088 case notsyntaxspec:
1089 fprintf (stderr, "/notsyntaxspec");
1090 mcnt = *p++;
1091 fprintf (stderr, "/%d", mcnt);
1092 break;
1094 # ifdef emacs
1095 case before_dot:
1096 fprintf (stderr, "/before_dot");
1097 break;
1099 case at_dot:
1100 fprintf (stderr, "/at_dot");
1101 break;
1103 case after_dot:
1104 fprintf (stderr, "/after_dot");
1105 break;
1107 case categoryspec:
1108 fprintf (stderr, "/categoryspec");
1109 mcnt = *p++;
1110 fprintf (stderr, "/%d", mcnt);
1111 break;
1113 case notcategoryspec:
1114 fprintf (stderr, "/notcategoryspec");
1115 mcnt = *p++;
1116 fprintf (stderr, "/%d", mcnt);
1117 break;
1118 # endif /* emacs */
1120 case begbuf:
1121 fprintf (stderr, "/begbuf");
1122 break;
1124 case endbuf:
1125 fprintf (stderr, "/endbuf");
1126 break;
1128 default:
1129 fprintf (stderr, "?%d", *(p-1));
1132 fprintf (stderr, "\n");
1135 fprintf (stderr, "%td:\tend of pattern.\n", p - start);
1139 static void
1140 print_compiled_pattern (struct re_pattern_buffer *bufp)
1142 re_char *buffer = bufp->buffer;
1144 print_partial_compiled_pattern (buffer, buffer + bufp->used);
1145 printf ("%ld bytes used/%ld bytes allocated.\n",
1146 bufp->used, bufp->allocated);
1148 if (bufp->fastmap_accurate && bufp->fastmap)
1150 printf ("fastmap: ");
1151 print_fastmap (bufp->fastmap);
1154 printf ("re_nsub: %zu\t", bufp->re_nsub);
1155 printf ("regs_alloc: %d\t", bufp->regs_allocated);
1156 printf ("can_be_null: %d\t", bufp->can_be_null);
1157 printf ("no_sub: %d\t", bufp->no_sub);
1158 printf ("not_bol: %d\t", bufp->not_bol);
1159 printf ("not_eol: %d\t", bufp->not_eol);
1160 printf ("syntax: %lx\n", bufp->syntax);
1161 fflush (stdout);
1162 /* Perhaps we should print the translate table? */
1166 static void
1167 print_double_string (re_char *where, re_char *string1, ssize_t size1,
1168 re_char *string2, ssize_t size2)
1170 ssize_t this_char;
1172 if (where == NULL)
1173 printf ("(null)");
1174 else
1176 if (FIRST_STRING_P (where))
1178 for (this_char = where - string1; this_char < size1; this_char++)
1179 putchar (string1[this_char]);
1181 where = string2;
1184 for (this_char = where - string2; this_char < size2; this_char++)
1185 putchar (string2[this_char]);
1189 #else /* not DEBUG */
1191 # undef assert
1192 # define assert(e)
1194 # define DEBUG_STATEMENT(e)
1195 # if __STDC_VERSION__ < 199901L
1196 # define DEBUG_COMPILES_ARGUMENTS
1197 # define DEBUG_PRINT /* 'DEBUG_PRINT (x, y)' discards X and Y. */ (void)
1198 # else
1199 # define DEBUG_PRINT(...)
1200 # endif
1201 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
1202 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
1204 #endif /* not DEBUG */
1206 /* Use this to suppress gcc's `...may be used before initialized' warnings. */
1207 #ifdef lint
1208 # define IF_LINT(Code) Code
1209 #else
1210 # define IF_LINT(Code) /* empty */
1211 #endif
1213 /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
1214 also be assigned to arbitrarily: each pattern buffer stores its own
1215 syntax, so it can be changed between regex compilations. */
1216 /* This has no initializer because initialized variables in Emacs
1217 become read-only after dumping. */
1218 reg_syntax_t re_syntax_options;
1221 /* Specify the precise syntax of regexps for compilation. This provides
1222 for compatibility for various utilities which historically have
1223 different, incompatible syntaxes.
1225 The argument SYNTAX is a bit mask comprised of the various bits
1226 defined in regex.h. We return the old syntax. */
1228 reg_syntax_t
1229 re_set_syntax (reg_syntax_t syntax)
1231 reg_syntax_t ret = re_syntax_options;
1233 re_syntax_options = syntax;
1234 return ret;
1236 WEAK_ALIAS (__re_set_syntax, re_set_syntax)
1238 /* Regexp to use to replace spaces, or NULL meaning don't. */
1239 static re_char *whitespace_regexp;
1241 void
1242 re_set_whitespace_regexp (const char *regexp)
1244 whitespace_regexp = (re_char *) regexp;
1246 WEAK_ALIAS (__re_set_syntax, re_set_syntax)
1248 /* This table gives an error message for each of the error codes listed
1249 in regex.h. Obviously the order here has to be same as there.
1250 POSIX doesn't require that we do anything for REG_NOERROR,
1251 but why not be nice? */
1253 static const char *re_error_msgid[] =
1255 gettext_noop ("Success"), /* REG_NOERROR */
1256 gettext_noop ("No match"), /* REG_NOMATCH */
1257 gettext_noop ("Invalid regular expression"), /* REG_BADPAT */
1258 gettext_noop ("Invalid collation character"), /* REG_ECOLLATE */
1259 gettext_noop ("Invalid character class name"), /* REG_ECTYPE */
1260 gettext_noop ("Trailing backslash"), /* REG_EESCAPE */
1261 gettext_noop ("Invalid back reference"), /* REG_ESUBREG */
1262 gettext_noop ("Unmatched [ or [^"), /* REG_EBRACK */
1263 gettext_noop ("Unmatched ( or \\("), /* REG_EPAREN */
1264 gettext_noop ("Unmatched \\{"), /* REG_EBRACE */
1265 gettext_noop ("Invalid content of \\{\\}"), /* REG_BADBR */
1266 gettext_noop ("Invalid range end"), /* REG_ERANGE */
1267 gettext_noop ("Memory exhausted"), /* REG_ESPACE */
1268 gettext_noop ("Invalid preceding regular expression"), /* REG_BADRPT */
1269 gettext_noop ("Premature end of regular expression"), /* REG_EEND */
1270 gettext_noop ("Regular expression too big"), /* REG_ESIZE */
1271 gettext_noop ("Unmatched ) or \\)"), /* REG_ERPAREN */
1272 gettext_noop ("Range striding over charsets") /* REG_ERANGEX */
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 /* The match routines may not allocate if (1) they would do it with malloc
1298 and (2) it's not safe for them to use malloc.
1299 Note that if REL_ALLOC is defined, matching would not use malloc for the
1300 failure stack, but we would still use it for the register vectors;
1301 so REL_ALLOC should not affect this. */
1302 #if defined REGEX_MALLOC && defined emacs
1303 # undef MATCH_MAY_ALLOCATE
1304 #endif
1307 /* Failure stack declarations and macros; both re_compile_fastmap and
1308 re_match_2 use a failure stack. These have to be macros because of
1309 REGEX_ALLOCATE_STACK. */
1312 /* Approximate number of failure points for which to initially allocate space
1313 when matching. If this number is exceeded, we allocate more
1314 space, so it is not a hard limit. */
1315 #ifndef INIT_FAILURE_ALLOC
1316 # define INIT_FAILURE_ALLOC 20
1317 #endif
1319 /* Roughly the maximum number of failure points on the stack. Would be
1320 exactly that if always used TYPICAL_FAILURE_SIZE items each time we failed.
1321 This is a variable only so users of regex can assign to it; we never
1322 change it ourselves. We always multiply it by TYPICAL_FAILURE_SIZE
1323 before using it, so it should probably be a byte-count instead. */
1324 # if defined MATCH_MAY_ALLOCATE
1325 /* Note that 4400 was enough to cause a crash on Alpha OSF/1,
1326 whose default stack limit is 2mb. In order for a larger
1327 value to work reliably, you have to try to make it accord
1328 with the process stack limit. */
1329 size_t re_max_failures = 40000;
1330 # else
1331 size_t re_max_failures = 4000;
1332 # endif
1334 union fail_stack_elt
1336 re_char *pointer;
1337 /* This should be the biggest `int' that's no bigger than a pointer. */
1338 long integer;
1341 typedef union fail_stack_elt fail_stack_elt_t;
1343 typedef struct
1345 fail_stack_elt_t *stack;
1346 size_t size;
1347 size_t avail; /* Offset of next open position. */
1348 size_t frame; /* Offset of the cur constructed frame. */
1349 } fail_stack_type;
1351 #define FAIL_STACK_EMPTY() (fail_stack.frame == 0)
1354 /* Define macros to initialize and free the failure stack.
1355 Do `return -2' if the alloc fails. */
1357 #ifdef MATCH_MAY_ALLOCATE
1358 # define INIT_FAIL_STACK() \
1359 do { \
1360 fail_stack.stack = \
1361 REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * TYPICAL_FAILURE_SIZE \
1362 * sizeof (fail_stack_elt_t)); \
1364 if (fail_stack.stack == NULL) \
1365 return -2; \
1367 fail_stack.size = INIT_FAILURE_ALLOC; \
1368 fail_stack.avail = 0; \
1369 fail_stack.frame = 0; \
1370 } while (0)
1371 #else
1372 # define INIT_FAIL_STACK() \
1373 do { \
1374 fail_stack.avail = 0; \
1375 fail_stack.frame = 0; \
1376 } while (0)
1378 # define RETALLOC_IF(addr, n, t) \
1379 if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
1380 #endif
1383 /* Double the size of FAIL_STACK, up to a limit
1384 which allows approximately `re_max_failures' items.
1386 Return 1 if succeeds, and 0 if either ran out of memory
1387 allocating space for it or it was already too large.
1389 REGEX_REALLOCATE_STACK requires `destination' be declared. */
1391 /* Factor to increase the failure stack size by
1392 when we increase it.
1393 This used to be 2, but 2 was too wasteful
1394 because the old discarded stacks added up to as much space
1395 were as ultimate, maximum-size stack. */
1396 #define FAIL_STACK_GROWTH_FACTOR 4
1398 #define GROW_FAIL_STACK(fail_stack) \
1399 (((fail_stack).size * sizeof (fail_stack_elt_t) \
1400 >= re_max_failures * TYPICAL_FAILURE_SIZE) \
1401 ? 0 \
1402 : ((fail_stack).stack \
1403 = REGEX_REALLOCATE_STACK ((fail_stack).stack, \
1404 (fail_stack).size * sizeof (fail_stack_elt_t), \
1405 MIN (re_max_failures * TYPICAL_FAILURE_SIZE, \
1406 ((fail_stack).size * sizeof (fail_stack_elt_t) \
1407 * FAIL_STACK_GROWTH_FACTOR))), \
1409 (fail_stack).stack == NULL \
1410 ? 0 \
1411 : ((fail_stack).size \
1412 = (MIN (re_max_failures * TYPICAL_FAILURE_SIZE, \
1413 ((fail_stack).size * sizeof (fail_stack_elt_t) \
1414 * FAIL_STACK_GROWTH_FACTOR)) \
1415 / sizeof (fail_stack_elt_t)), \
1416 1)))
1419 /* Push a pointer value onto the failure stack.
1420 Assumes the variable `fail_stack'. Probably should only
1421 be called from within `PUSH_FAILURE_POINT'. */
1422 #define PUSH_FAILURE_POINTER(item) \
1423 fail_stack.stack[fail_stack.avail++].pointer = (item)
1425 /* This pushes an integer-valued item onto the failure stack.
1426 Assumes the variable `fail_stack'. Probably should only
1427 be called from within `PUSH_FAILURE_POINT'. */
1428 #define PUSH_FAILURE_INT(item) \
1429 fail_stack.stack[fail_stack.avail++].integer = (item)
1431 /* These POP... operations complement the PUSH... operations.
1432 All assume that `fail_stack' is nonempty. */
1433 #define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
1434 #define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
1436 /* Individual items aside from the registers. */
1437 #define NUM_NONREG_ITEMS 3
1439 /* Used to examine the stack (to detect infinite loops). */
1440 #define FAILURE_PAT(h) fail_stack.stack[(h) - 1].pointer
1441 #define FAILURE_STR(h) (fail_stack.stack[(h) - 2].pointer)
1442 #define NEXT_FAILURE_HANDLE(h) fail_stack.stack[(h) - 3].integer
1443 #define TOP_FAILURE_HANDLE() fail_stack.frame
1446 #define ENSURE_FAIL_STACK(space) \
1447 while (REMAINING_AVAIL_SLOTS <= space) { \
1448 if (!GROW_FAIL_STACK (fail_stack)) \
1449 return -2; \
1450 DEBUG_PRINT ("\n Doubled stack; size now: %zd\n", (fail_stack).size);\
1451 DEBUG_PRINT (" slots available: %zd\n", REMAINING_AVAIL_SLOTS);\
1454 /* Push register NUM onto the stack. */
1455 #define PUSH_FAILURE_REG(num) \
1456 do { \
1457 char *destination; \
1458 long n = num; \
1459 ENSURE_FAIL_STACK(3); \
1460 DEBUG_PRINT (" Push reg %ld (spanning %p -> %p)\n", \
1461 n, regstart[n], regend[n]); \
1462 PUSH_FAILURE_POINTER (regstart[n]); \
1463 PUSH_FAILURE_POINTER (regend[n]); \
1464 PUSH_FAILURE_INT (n); \
1465 } while (0)
1467 /* Change the counter's value to VAL, but make sure that it will
1468 be reset when backtracking. */
1469 #define PUSH_NUMBER(ptr,val) \
1470 do { \
1471 char *destination; \
1472 int c; \
1473 ENSURE_FAIL_STACK(3); \
1474 EXTRACT_NUMBER (c, ptr); \
1475 DEBUG_PRINT (" Push number %p = %d -> %d\n", ptr, c, val); \
1476 PUSH_FAILURE_INT (c); \
1477 PUSH_FAILURE_POINTER (ptr); \
1478 PUSH_FAILURE_INT (-1); \
1479 STORE_NUMBER (ptr, val); \
1480 } while (0)
1482 /* Pop a saved register off the stack. */
1483 #define POP_FAILURE_REG_OR_COUNT() \
1484 do { \
1485 long pfreg = POP_FAILURE_INT (); \
1486 if (pfreg == -1) \
1488 /* It's a counter. */ \
1489 /* Here, we discard `const', making re_match non-reentrant. */ \
1490 unsigned char *ptr = (unsigned char*) POP_FAILURE_POINTER (); \
1491 pfreg = POP_FAILURE_INT (); \
1492 STORE_NUMBER (ptr, pfreg); \
1493 DEBUG_PRINT (" Pop counter %p = %ld\n", ptr, pfreg); \
1495 else \
1497 regend[pfreg] = POP_FAILURE_POINTER (); \
1498 regstart[pfreg] = POP_FAILURE_POINTER (); \
1499 DEBUG_PRINT (" Pop reg %ld (spanning %p -> %p)\n", \
1500 pfreg, regstart[pfreg], regend[pfreg]); \
1502 } while (0)
1504 /* Check that we are not stuck in an infinite loop. */
1505 #define CHECK_INFINITE_LOOP(pat_cur, string_place) \
1506 do { \
1507 ssize_t failure = TOP_FAILURE_HANDLE (); \
1508 /* Check for infinite matching loops */ \
1509 while (failure > 0 \
1510 && (FAILURE_STR (failure) == string_place \
1511 || FAILURE_STR (failure) == NULL)) \
1513 assert (FAILURE_PAT (failure) >= bufp->buffer \
1514 && FAILURE_PAT (failure) <= bufp->buffer + bufp->used); \
1515 if (FAILURE_PAT (failure) == pat_cur) \
1517 cycle = 1; \
1518 break; \
1520 DEBUG_PRINT (" Other pattern: %p\n", FAILURE_PAT (failure)); \
1521 failure = NEXT_FAILURE_HANDLE(failure); \
1523 DEBUG_PRINT (" Other string: %p\n", FAILURE_STR (failure)); \
1524 } while (0)
1526 /* Push the information about the state we will need
1527 if we ever fail back to it.
1529 Requires variables fail_stack, regstart, regend and
1530 num_regs be declared. GROW_FAIL_STACK requires `destination' be
1531 declared.
1533 Does `return FAILURE_CODE' if runs out of memory. */
1535 #define PUSH_FAILURE_POINT(pattern, string_place) \
1536 do { \
1537 char *destination; \
1538 /* Must be int, so when we don't save any registers, the arithmetic \
1539 of 0 + -1 isn't done as unsigned. */ \
1541 DEBUG_STATEMENT (nfailure_points_pushed++); \
1542 DEBUG_PRINT ("\nPUSH_FAILURE_POINT:\n"); \
1543 DEBUG_PRINT (" Before push, next avail: %zd\n", (fail_stack).avail); \
1544 DEBUG_PRINT (" size: %zd\n", (fail_stack).size);\
1546 ENSURE_FAIL_STACK (NUM_NONREG_ITEMS); \
1548 DEBUG_PRINT ("\n"); \
1550 DEBUG_PRINT (" Push frame index: %zd\n", fail_stack.frame); \
1551 PUSH_FAILURE_INT (fail_stack.frame); \
1553 DEBUG_PRINT (" Push string %p: `", string_place); \
1554 DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2, size2);\
1555 DEBUG_PRINT ("'\n"); \
1556 PUSH_FAILURE_POINTER (string_place); \
1558 DEBUG_PRINT (" Push pattern %p: ", pattern); \
1559 DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern, pend); \
1560 PUSH_FAILURE_POINTER (pattern); \
1562 /* Close the frame by moving the frame pointer past it. */ \
1563 fail_stack.frame = fail_stack.avail; \
1564 } while (0)
1566 /* Estimate the size of data pushed by a typical failure stack entry.
1567 An estimate is all we need, because all we use this for
1568 is to choose a limit for how big to make the failure stack. */
1569 /* BEWARE, the value `20' is hard-coded in emacs.c:main(). */
1570 #define TYPICAL_FAILURE_SIZE 20
1572 /* How many items can still be added to the stack without overflowing it. */
1573 #define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
1576 /* Pops what PUSH_FAIL_STACK pushes.
1578 We restore into the parameters, all of which should be lvalues:
1579 STR -- the saved data position.
1580 PAT -- the saved pattern position.
1581 REGSTART, REGEND -- arrays of string positions.
1583 Also assumes the variables `fail_stack' and (if debugging), `bufp',
1584 `pend', `string1', `size1', `string2', and `size2'. */
1586 #define POP_FAILURE_POINT(str, pat) \
1587 do { \
1588 assert (!FAIL_STACK_EMPTY ()); \
1590 /* Remove failure points and point to how many regs pushed. */ \
1591 DEBUG_PRINT ("POP_FAILURE_POINT:\n"); \
1592 DEBUG_PRINT (" Before pop, next avail: %zd\n", fail_stack.avail); \
1593 DEBUG_PRINT (" size: %zd\n", fail_stack.size); \
1595 /* Pop the saved registers. */ \
1596 while (fail_stack.frame < fail_stack.avail) \
1597 POP_FAILURE_REG_OR_COUNT (); \
1599 pat = POP_FAILURE_POINTER (); \
1600 DEBUG_PRINT (" Popping pattern %p: ", pat); \
1601 DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend); \
1603 /* If the saved string location is NULL, it came from an \
1604 on_failure_keep_string_jump opcode, and we want to throw away the \
1605 saved NULL, thus retaining our current position in the string. */ \
1606 str = POP_FAILURE_POINTER (); \
1607 DEBUG_PRINT (" Popping string %p: `", str); \
1608 DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2); \
1609 DEBUG_PRINT ("'\n"); \
1611 fail_stack.frame = POP_FAILURE_INT (); \
1612 DEBUG_PRINT (" Popping frame index: %zd\n", fail_stack.frame); \
1614 assert (fail_stack.avail >= 0); \
1615 assert (fail_stack.frame <= fail_stack.avail); \
1617 DEBUG_STATEMENT (nfailure_points_popped++); \
1618 } while (0) /* POP_FAILURE_POINT */
1622 /* Registers are set to a sentinel when they haven't yet matched. */
1623 #define REG_UNSET(e) ((e) == NULL)
1625 /* Subroutine declarations and macros for regex_compile. */
1627 static reg_errcode_t regex_compile (re_char *pattern, size_t size,
1628 reg_syntax_t syntax,
1629 struct re_pattern_buffer *bufp);
1630 static void store_op1 (re_opcode_t op, unsigned char *loc, int arg);
1631 static void store_op2 (re_opcode_t op, unsigned char *loc, int arg1, int arg2);
1632 static void insert_op1 (re_opcode_t op, unsigned char *loc,
1633 int arg, unsigned char *end);
1634 static void insert_op2 (re_opcode_t op, unsigned char *loc,
1635 int arg1, int arg2, unsigned char *end);
1636 static boolean at_begline_loc_p (re_char *pattern, re_char *p,
1637 reg_syntax_t syntax);
1638 static boolean at_endline_loc_p (re_char *p, re_char *pend,
1639 reg_syntax_t syntax);
1640 static re_char *skip_one_char (re_char *p);
1641 static int analyse_first (re_char *p, re_char *pend,
1642 char *fastmap, const int multibyte);
1644 /* Fetch the next character in the uncompiled pattern, with no
1645 translation. */
1646 #define PATFETCH(c) \
1647 do { \
1648 int len; \
1649 if (p == pend) return REG_EEND; \
1650 c = RE_STRING_CHAR_AND_LENGTH (p, len, multibyte); \
1651 p += len; \
1652 } while (0)
1655 /* If `translate' is non-null, return translate[D], else just D. We
1656 cast the subscript to translate because some data is declared as
1657 `char *', to avoid warnings when a string constant is passed. But
1658 when we use a character as a subscript we must make it unsigned. */
1659 #ifndef TRANSLATE
1660 # define TRANSLATE(d) \
1661 (RE_TRANSLATE_P (translate) ? RE_TRANSLATE (translate, (d)) : (d))
1662 #endif
1665 /* Macros for outputting the compiled pattern into `buffer'. */
1667 /* If the buffer isn't allocated when it comes in, use this. */
1668 #define INIT_BUF_SIZE 32
1670 /* Make sure we have at least N more bytes of space in buffer. */
1671 #define GET_BUFFER_SPACE(n) \
1672 while ((size_t) (b - bufp->buffer + (n)) > bufp->allocated) \
1673 EXTEND_BUFFER ()
1675 /* Make sure we have one more byte of buffer space and then add C to it. */
1676 #define BUF_PUSH(c) \
1677 do { \
1678 GET_BUFFER_SPACE (1); \
1679 *b++ = (unsigned char) (c); \
1680 } while (0)
1683 /* Ensure we have two more bytes of buffer space and then append C1 and C2. */
1684 #define BUF_PUSH_2(c1, c2) \
1685 do { \
1686 GET_BUFFER_SPACE (2); \
1687 *b++ = (unsigned char) (c1); \
1688 *b++ = (unsigned char) (c2); \
1689 } while (0)
1692 /* Store a jump with opcode OP at LOC to location TO. We store a
1693 relative address offset by the three bytes the jump itself occupies. */
1694 #define STORE_JUMP(op, loc, to) \
1695 store_op1 (op, loc, (to) - (loc) - 3)
1697 /* Likewise, for a two-argument jump. */
1698 #define STORE_JUMP2(op, loc, to, arg) \
1699 store_op2 (op, loc, (to) - (loc) - 3, arg)
1701 /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
1702 #define INSERT_JUMP(op, loc, to) \
1703 insert_op1 (op, loc, (to) - (loc) - 3, b)
1705 /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
1706 #define INSERT_JUMP2(op, loc, to, arg) \
1707 insert_op2 (op, loc, (to) - (loc) - 3, arg, b)
1710 /* This is not an arbitrary limit: the arguments which represent offsets
1711 into the pattern are two bytes long. So if 2^15 bytes turns out to
1712 be too small, many things would have to change. */
1713 # define MAX_BUF_SIZE (1L << 15)
1715 /* Extend the buffer by twice its current size via realloc and
1716 reset the pointers that pointed into the old block to point to the
1717 correct places in the new one. If extending the buffer results in it
1718 being larger than MAX_BUF_SIZE, then flag memory exhausted. */
1719 #if __BOUNDED_POINTERS__
1720 # define SET_HIGH_BOUND(P) (__ptrhigh (P) = __ptrlow (P) + bufp->allocated)
1721 # define MOVE_BUFFER_POINTER(P) \
1722 (__ptrlow (P) = new_buffer + (__ptrlow (P) - old_buffer), \
1723 SET_HIGH_BOUND (P), \
1724 __ptrvalue (P) = new_buffer + (__ptrvalue (P) - old_buffer))
1725 # define ELSE_EXTEND_BUFFER_HIGH_BOUND \
1726 else \
1728 SET_HIGH_BOUND (b); \
1729 SET_HIGH_BOUND (begalt); \
1730 if (fixup_alt_jump) \
1731 SET_HIGH_BOUND (fixup_alt_jump); \
1732 if (laststart) \
1733 SET_HIGH_BOUND (laststart); \
1734 if (pending_exact) \
1735 SET_HIGH_BOUND (pending_exact); \
1737 #else
1738 # define MOVE_BUFFER_POINTER(P) ((P) = new_buffer + ((P) - old_buffer))
1739 # define ELSE_EXTEND_BUFFER_HIGH_BOUND
1740 #endif
1741 #define EXTEND_BUFFER() \
1742 do { \
1743 unsigned char *old_buffer = bufp->buffer; \
1744 if (bufp->allocated == MAX_BUF_SIZE) \
1745 return REG_ESIZE; \
1746 bufp->allocated <<= 1; \
1747 if (bufp->allocated > MAX_BUF_SIZE) \
1748 bufp->allocated = MAX_BUF_SIZE; \
1749 RETALLOC (bufp->buffer, bufp->allocated, unsigned char); \
1750 if (bufp->buffer == NULL) \
1751 return REG_ESPACE; \
1752 /* If the buffer moved, move all the pointers into it. */ \
1753 if (old_buffer != bufp->buffer) \
1755 unsigned char *new_buffer = bufp->buffer; \
1756 MOVE_BUFFER_POINTER (b); \
1757 MOVE_BUFFER_POINTER (begalt); \
1758 if (fixup_alt_jump) \
1759 MOVE_BUFFER_POINTER (fixup_alt_jump); \
1760 if (laststart) \
1761 MOVE_BUFFER_POINTER (laststart); \
1762 if (pending_exact) \
1763 MOVE_BUFFER_POINTER (pending_exact); \
1765 ELSE_EXTEND_BUFFER_HIGH_BOUND \
1766 } while (0)
1769 /* Since we have one byte reserved for the register number argument to
1770 {start,stop}_memory, the maximum number of groups we can report
1771 things about is what fits in that byte. */
1772 #define MAX_REGNUM 255
1774 /* But patterns can have more than `MAX_REGNUM' registers. We just
1775 ignore the excess. */
1776 typedef int regnum_t;
1779 /* Macros for the compile stack. */
1781 /* Since offsets can go either forwards or backwards, this type needs to
1782 be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
1783 /* int may be not enough when sizeof(int) == 2. */
1784 typedef long pattern_offset_t;
1786 typedef struct
1788 pattern_offset_t begalt_offset;
1789 pattern_offset_t fixup_alt_jump;
1790 pattern_offset_t laststart_offset;
1791 regnum_t regnum;
1792 } compile_stack_elt_t;
1795 typedef struct
1797 compile_stack_elt_t *stack;
1798 size_t size;
1799 size_t avail; /* Offset of next open position. */
1800 } compile_stack_type;
1803 #define INIT_COMPILE_STACK_SIZE 32
1805 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
1806 #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
1808 /* The next available element. */
1809 #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
1811 /* Explicit quit checking is needed for Emacs, which uses polling to
1812 process input events. */
1813 #ifdef emacs
1814 # define IMMEDIATE_QUIT_CHECK \
1815 do { \
1816 if (immediate_quit) QUIT; \
1817 } while (0)
1818 #else
1819 # define IMMEDIATE_QUIT_CHECK ((void)0)
1820 #endif
1822 /* Structure to manage work area for range table. */
1823 struct range_table_work_area
1825 int *table; /* actual work area. */
1826 int allocated; /* allocated size for work area in bytes. */
1827 int used; /* actually used size in words. */
1828 int bits; /* flag to record character classes */
1831 /* Make sure that WORK_AREA can hold more N multibyte characters.
1832 This is used only in set_image_of_range and set_image_of_range_1.
1833 It expects WORK_AREA to be a pointer.
1834 If it can't get the space, it returns from the surrounding function. */
1836 #define EXTEND_RANGE_TABLE(work_area, n) \
1837 do { \
1838 if (((work_area).used + (n)) * sizeof (int) > (work_area).allocated) \
1840 extend_range_table_work_area (&work_area); \
1841 if ((work_area).table == 0) \
1842 return (REG_ESPACE); \
1844 } while (0)
1846 #define SET_RANGE_TABLE_WORK_AREA_BIT(work_area, bit) \
1847 (work_area).bits |= (bit)
1849 /* Bits used to implement the multibyte-part of the various character classes
1850 such as [:alnum:] in a charset's range table. */
1851 #define BIT_WORD 0x1
1852 #define BIT_LOWER 0x2
1853 #define BIT_PUNCT 0x4
1854 #define BIT_SPACE 0x8
1855 #define BIT_UPPER 0x10
1856 #define BIT_MULTIBYTE 0x20
1858 /* Set a range (RANGE_START, RANGE_END) to WORK_AREA. */
1859 #define SET_RANGE_TABLE_WORK_AREA(work_area, range_start, range_end) \
1860 do { \
1861 EXTEND_RANGE_TABLE ((work_area), 2); \
1862 (work_area).table[(work_area).used++] = (range_start); \
1863 (work_area).table[(work_area).used++] = (range_end); \
1864 } while (0)
1866 /* Free allocated memory for WORK_AREA. */
1867 #define FREE_RANGE_TABLE_WORK_AREA(work_area) \
1868 do { \
1869 if ((work_area).table) \
1870 free ((work_area).table); \
1871 } while (0)
1873 #define CLEAR_RANGE_TABLE_WORK_USED(work_area) ((work_area).used = 0, (work_area).bits = 0)
1874 #define RANGE_TABLE_WORK_USED(work_area) ((work_area).used)
1875 #define RANGE_TABLE_WORK_BITS(work_area) ((work_area).bits)
1876 #define RANGE_TABLE_WORK_ELT(work_area, i) ((work_area).table[i])
1879 /* Set the bit for character C in a list. */
1880 #define SET_LIST_BIT(c) (b[((c)) / BYTEWIDTH] |= 1 << ((c) % BYTEWIDTH))
1883 #ifdef emacs
1885 /* Store characters in the range FROM to TO in the bitmap at B (for
1886 ASCII and unibyte characters) and WORK_AREA (for multibyte
1887 characters) while translating them and paying attention to the
1888 continuity of translated characters.
1890 Implementation note: It is better to implement these fairly big
1891 macros by a function, but it's not that easy because macros called
1892 in this macro assume various local variables already declared. */
1894 /* Both FROM and TO are ASCII characters. */
1896 #define SETUP_ASCII_RANGE(work_area, FROM, TO) \
1897 do { \
1898 int C0, C1; \
1900 for (C0 = (FROM); C0 <= (TO); C0++) \
1902 C1 = TRANSLATE (C0); \
1903 if (! ASCII_CHAR_P (C1)) \
1905 SET_RANGE_TABLE_WORK_AREA ((work_area), C1, C1); \
1906 if ((C1 = RE_CHAR_TO_UNIBYTE (C1)) < 0) \
1907 C1 = C0; \
1909 SET_LIST_BIT (C1); \
1911 } while (0)
1914 /* Both FROM and TO are unibyte characters (0x80..0xFF). */
1916 #define SETUP_UNIBYTE_RANGE(work_area, FROM, TO) \
1917 do { \
1918 int C0, C1, C2, I; \
1919 int USED = RANGE_TABLE_WORK_USED (work_area); \
1921 for (C0 = (FROM); C0 <= (TO); C0++) \
1923 C1 = RE_CHAR_TO_MULTIBYTE (C0); \
1924 if (CHAR_BYTE8_P (C1)) \
1925 SET_LIST_BIT (C0); \
1926 else \
1928 C2 = TRANSLATE (C1); \
1929 if (C2 == C1 \
1930 || (C1 = RE_CHAR_TO_UNIBYTE (C2)) < 0) \
1931 C1 = C0; \
1932 SET_LIST_BIT (C1); \
1933 for (I = RANGE_TABLE_WORK_USED (work_area) - 2; I >= USED; I -= 2) \
1935 int from = RANGE_TABLE_WORK_ELT (work_area, I); \
1936 int to = RANGE_TABLE_WORK_ELT (work_area, I + 1); \
1938 if (C2 >= from - 1 && C2 <= to + 1) \
1940 if (C2 == from - 1) \
1941 RANGE_TABLE_WORK_ELT (work_area, I)--; \
1942 else if (C2 == to + 1) \
1943 RANGE_TABLE_WORK_ELT (work_area, I + 1)++; \
1944 break; \
1947 if (I < USED) \
1948 SET_RANGE_TABLE_WORK_AREA ((work_area), C2, C2); \
1951 } while (0)
1954 /* Both FROM and TO are multibyte characters. */
1956 #define SETUP_MULTIBYTE_RANGE(work_area, FROM, TO) \
1957 do { \
1958 int C0, C1, C2, I, USED = RANGE_TABLE_WORK_USED (work_area); \
1960 SET_RANGE_TABLE_WORK_AREA ((work_area), (FROM), (TO)); \
1961 for (C0 = (FROM); C0 <= (TO); C0++) \
1963 C1 = TRANSLATE (C0); \
1964 if ((C2 = RE_CHAR_TO_UNIBYTE (C1)) >= 0 \
1965 || (C1 != C0 && (C2 = RE_CHAR_TO_UNIBYTE (C0)) >= 0)) \
1966 SET_LIST_BIT (C2); \
1967 if (C1 >= (FROM) && C1 <= (TO)) \
1968 continue; \
1969 for (I = RANGE_TABLE_WORK_USED (work_area) - 2; I >= USED; I -= 2) \
1971 int from = RANGE_TABLE_WORK_ELT (work_area, I); \
1972 int to = RANGE_TABLE_WORK_ELT (work_area, I + 1); \
1974 if (C1 >= from - 1 && C1 <= to + 1) \
1976 if (C1 == from - 1) \
1977 RANGE_TABLE_WORK_ELT (work_area, I)--; \
1978 else if (C1 == to + 1) \
1979 RANGE_TABLE_WORK_ELT (work_area, I + 1)++; \
1980 break; \
1983 if (I < USED) \
1984 SET_RANGE_TABLE_WORK_AREA ((work_area), C1, C1); \
1986 } while (0)
1988 #endif /* emacs */
1990 /* Get the next unsigned number in the uncompiled pattern. */
1991 #define GET_UNSIGNED_NUMBER(num) \
1992 do { \
1993 if (p == pend) \
1994 FREE_STACK_RETURN (REG_EBRACE); \
1995 else \
1997 PATFETCH (c); \
1998 while ('0' <= c && c <= '9') \
2000 int prev; \
2001 if (num < 0) \
2002 num = 0; \
2003 prev = num; \
2004 num = num * 10 + c - '0'; \
2005 if (num / 10 != prev) \
2006 FREE_STACK_RETURN (REG_BADBR); \
2007 if (p == pend) \
2008 FREE_STACK_RETURN (REG_EBRACE); \
2009 PATFETCH (c); \
2012 } while (0)
2014 #if ! WIDE_CHAR_SUPPORT
2016 /* Map a string to the char class it names (if any). */
2017 re_wctype_t
2018 re_wctype (const re_char *str)
2020 const char *string = (const char *) str;
2021 if (STREQ (string, "alnum")) return RECC_ALNUM;
2022 else if (STREQ (string, "alpha")) return RECC_ALPHA;
2023 else if (STREQ (string, "word")) return RECC_WORD;
2024 else if (STREQ (string, "ascii")) return RECC_ASCII;
2025 else if (STREQ (string, "nonascii")) return RECC_NONASCII;
2026 else if (STREQ (string, "graph")) return RECC_GRAPH;
2027 else if (STREQ (string, "lower")) return RECC_LOWER;
2028 else if (STREQ (string, "print")) return RECC_PRINT;
2029 else if (STREQ (string, "punct")) return RECC_PUNCT;
2030 else if (STREQ (string, "space")) return RECC_SPACE;
2031 else if (STREQ (string, "upper")) return RECC_UPPER;
2032 else if (STREQ (string, "unibyte")) return RECC_UNIBYTE;
2033 else if (STREQ (string, "multibyte")) return RECC_MULTIBYTE;
2034 else if (STREQ (string, "digit")) return RECC_DIGIT;
2035 else if (STREQ (string, "xdigit")) return RECC_XDIGIT;
2036 else if (STREQ (string, "cntrl")) return RECC_CNTRL;
2037 else if (STREQ (string, "blank")) return RECC_BLANK;
2038 else return 0;
2041 /* True if CH is in the char class CC. */
2042 boolean
2043 re_iswctype (int ch, re_wctype_t cc)
2045 switch (cc)
2047 case RECC_ALNUM: return ISALNUM (ch) != 0;
2048 case RECC_ALPHA: return ISALPHA (ch) != 0;
2049 case RECC_BLANK: return ISBLANK (ch) != 0;
2050 case RECC_CNTRL: return ISCNTRL (ch) != 0;
2051 case RECC_DIGIT: return ISDIGIT (ch) != 0;
2052 case RECC_GRAPH: return ISGRAPH (ch) != 0;
2053 case RECC_LOWER: return ISLOWER (ch) != 0;
2054 case RECC_PRINT: return ISPRINT (ch) != 0;
2055 case RECC_PUNCT: return ISPUNCT (ch) != 0;
2056 case RECC_SPACE: return ISSPACE (ch) != 0;
2057 case RECC_UPPER: return ISUPPER (ch) != 0;
2058 case RECC_XDIGIT: return ISXDIGIT (ch) != 0;
2059 case RECC_ASCII: return IS_REAL_ASCII (ch) != 0;
2060 case RECC_NONASCII: return !IS_REAL_ASCII (ch);
2061 case RECC_UNIBYTE: return ISUNIBYTE (ch) != 0;
2062 case RECC_MULTIBYTE: return !ISUNIBYTE (ch);
2063 case RECC_WORD: return ISWORD (ch) != 0;
2064 case RECC_ERROR: return false;
2065 default:
2066 abort ();
2070 /* Return a bit-pattern to use in the range-table bits to match multibyte
2071 chars of class CC. */
2072 static int
2073 re_wctype_to_bit (re_wctype_t cc)
2075 switch (cc)
2077 case RECC_NONASCII: case RECC_PRINT: case RECC_GRAPH:
2078 case RECC_MULTIBYTE: return BIT_MULTIBYTE;
2079 case RECC_ALPHA: case RECC_ALNUM: case RECC_WORD: return BIT_WORD;
2080 case RECC_LOWER: return BIT_LOWER;
2081 case RECC_UPPER: return BIT_UPPER;
2082 case RECC_PUNCT: return BIT_PUNCT;
2083 case RECC_SPACE: return BIT_SPACE;
2084 case RECC_ASCII: case RECC_DIGIT: case RECC_XDIGIT: case RECC_CNTRL:
2085 case RECC_BLANK: case RECC_UNIBYTE: case RECC_ERROR: return 0;
2086 default:
2087 abort ();
2090 #endif
2092 /* Filling in the work area of a range. */
2094 /* Actually extend the space in WORK_AREA. */
2096 static void
2097 extend_range_table_work_area (struct range_table_work_area *work_area)
2099 work_area->allocated += 16 * sizeof (int);
2100 work_area->table = realloc (work_area->table, work_area->allocated);
2103 #if 0
2104 #ifdef emacs
2106 /* Carefully find the ranges of codes that are equivalent
2107 under case conversion to the range start..end when passed through
2108 TRANSLATE. Handle the case where non-letters can come in between
2109 two upper-case letters (which happens in Latin-1).
2110 Also handle the case of groups of more than 2 case-equivalent chars.
2112 The basic method is to look at consecutive characters and see
2113 if they can form a run that can be handled as one.
2115 Returns -1 if successful, REG_ESPACE if ran out of space. */
2117 static int
2118 set_image_of_range_1 (struct range_table_work_area *work_area,
2119 re_wchar_t start, re_wchar_t end,
2120 RE_TRANSLATE_TYPE translate)
2122 /* `one_case' indicates a character, or a run of characters,
2123 each of which is an isolate (no case-equivalents).
2124 This includes all ASCII non-letters.
2126 `two_case' indicates a character, or a run of characters,
2127 each of which has two case-equivalent forms.
2128 This includes all ASCII letters.
2130 `strange' indicates a character that has more than one
2131 case-equivalent. */
2133 enum case_type {one_case, two_case, strange};
2135 /* Describe the run that is in progress,
2136 which the next character can try to extend.
2137 If run_type is strange, that means there really is no run.
2138 If run_type is one_case, then run_start...run_end is the run.
2139 If run_type is two_case, then the run is run_start...run_end,
2140 and the case-equivalents end at run_eqv_end. */
2142 enum case_type run_type = strange;
2143 int run_start, run_end, run_eqv_end;
2145 Lisp_Object eqv_table;
2147 if (!RE_TRANSLATE_P (translate))
2149 EXTEND_RANGE_TABLE (work_area, 2);
2150 work_area->table[work_area->used++] = (start);
2151 work_area->table[work_area->used++] = (end);
2152 return -1;
2155 eqv_table = XCHAR_TABLE (translate)->extras[2];
2157 for (; start <= end; start++)
2159 enum case_type this_type;
2160 int eqv = RE_TRANSLATE (eqv_table, start);
2161 int minchar, maxchar;
2163 /* Classify this character */
2164 if (eqv == start)
2165 this_type = one_case;
2166 else if (RE_TRANSLATE (eqv_table, eqv) == start)
2167 this_type = two_case;
2168 else
2169 this_type = strange;
2171 if (start < eqv)
2172 minchar = start, maxchar = eqv;
2173 else
2174 minchar = eqv, maxchar = start;
2176 /* Can this character extend the run in progress? */
2177 if (this_type == strange || this_type != run_type
2178 || !(minchar == run_end + 1
2179 && (run_type == two_case
2180 ? maxchar == run_eqv_end + 1 : 1)))
2182 /* No, end the run.
2183 Record each of its equivalent ranges. */
2184 if (run_type == one_case)
2186 EXTEND_RANGE_TABLE (work_area, 2);
2187 work_area->table[work_area->used++] = run_start;
2188 work_area->table[work_area->used++] = run_end;
2190 else if (run_type == two_case)
2192 EXTEND_RANGE_TABLE (work_area, 4);
2193 work_area->table[work_area->used++] = run_start;
2194 work_area->table[work_area->used++] = run_end;
2195 work_area->table[work_area->used++]
2196 = RE_TRANSLATE (eqv_table, run_start);
2197 work_area->table[work_area->used++]
2198 = RE_TRANSLATE (eqv_table, run_end);
2200 run_type = strange;
2203 if (this_type == strange)
2205 /* For a strange character, add each of its equivalents, one
2206 by one. Don't start a range. */
2209 EXTEND_RANGE_TABLE (work_area, 2);
2210 work_area->table[work_area->used++] = eqv;
2211 work_area->table[work_area->used++] = eqv;
2212 eqv = RE_TRANSLATE (eqv_table, eqv);
2214 while (eqv != start);
2217 /* Add this char to the run, or start a new run. */
2218 else if (run_type == strange)
2220 /* Initialize a new range. */
2221 run_type = this_type;
2222 run_start = start;
2223 run_end = start;
2224 run_eqv_end = RE_TRANSLATE (eqv_table, run_end);
2226 else
2228 /* Extend a running range. */
2229 run_end = minchar;
2230 run_eqv_end = RE_TRANSLATE (eqv_table, run_end);
2234 /* If a run is still in progress at the end, finish it now
2235 by recording its equivalent ranges. */
2236 if (run_type == one_case)
2238 EXTEND_RANGE_TABLE (work_area, 2);
2239 work_area->table[work_area->used++] = run_start;
2240 work_area->table[work_area->used++] = run_end;
2242 else if (run_type == two_case)
2244 EXTEND_RANGE_TABLE (work_area, 4);
2245 work_area->table[work_area->used++] = run_start;
2246 work_area->table[work_area->used++] = run_end;
2247 work_area->table[work_area->used++]
2248 = RE_TRANSLATE (eqv_table, run_start);
2249 work_area->table[work_area->used++]
2250 = RE_TRANSLATE (eqv_table, run_end);
2253 return -1;
2256 #endif /* emacs */
2258 /* Record the image of the range start..end when passed through
2259 TRANSLATE. This is not necessarily TRANSLATE(start)..TRANSLATE(end)
2260 and is not even necessarily contiguous.
2261 Normally we approximate it with the smallest contiguous range that contains
2262 all the chars we need. However, for Latin-1 we go to extra effort
2263 to do a better job.
2265 This function is not called for ASCII ranges.
2267 Returns -1 if successful, REG_ESPACE if ran out of space. */
2269 static int
2270 set_image_of_range (struct range_table_work_area *work_area,
2271 re_wchar_t start, re_wchar_t end,
2272 RE_TRANSLATE_TYPE translate)
2274 re_wchar_t cmin, cmax;
2276 #ifdef emacs
2277 /* For Latin-1 ranges, use set_image_of_range_1
2278 to get proper handling of ranges that include letters and nonletters.
2279 For a range that includes the whole of Latin-1, this is not necessary.
2280 For other character sets, we don't bother to get this right. */
2281 if (RE_TRANSLATE_P (translate) && start < 04400
2282 && !(start < 04200 && end >= 04377))
2284 int newend;
2285 int tem;
2286 newend = end;
2287 if (newend > 04377)
2288 newend = 04377;
2289 tem = set_image_of_range_1 (work_area, start, newend, translate);
2290 if (tem > 0)
2291 return tem;
2293 start = 04400;
2294 if (end < 04400)
2295 return -1;
2297 #endif
2299 EXTEND_RANGE_TABLE (work_area, 2);
2300 work_area->table[work_area->used++] = (start);
2301 work_area->table[work_area->used++] = (end);
2303 cmin = -1, cmax = -1;
2305 if (RE_TRANSLATE_P (translate))
2307 int ch;
2309 for (ch = start; ch <= end; ch++)
2311 re_wchar_t c = TRANSLATE (ch);
2312 if (! (start <= c && c <= end))
2314 if (cmin == -1)
2315 cmin = c, cmax = c;
2316 else
2318 cmin = MIN (cmin, c);
2319 cmax = MAX (cmax, c);
2324 if (cmin != -1)
2326 EXTEND_RANGE_TABLE (work_area, 2);
2327 work_area->table[work_area->used++] = (cmin);
2328 work_area->table[work_area->used++] = (cmax);
2332 return -1;
2334 #endif /* 0 */
2336 #ifndef MATCH_MAY_ALLOCATE
2338 /* If we cannot allocate large objects within re_match_2_internal,
2339 we make the fail stack and register vectors global.
2340 The fail stack, we grow to the maximum size when a regexp
2341 is compiled.
2342 The register vectors, we adjust in size each time we
2343 compile a regexp, according to the number of registers it needs. */
2345 static fail_stack_type fail_stack;
2347 /* Size with which the following vectors are currently allocated.
2348 That is so we can make them bigger as needed,
2349 but never make them smaller. */
2350 static int regs_allocated_size;
2352 static re_char ** regstart, ** regend;
2353 static re_char **best_regstart, **best_regend;
2355 /* Make the register vectors big enough for NUM_REGS registers,
2356 but don't make them smaller. */
2358 static
2359 regex_grow_registers (int num_regs)
2361 if (num_regs > regs_allocated_size)
2363 RETALLOC_IF (regstart, num_regs, re_char *);
2364 RETALLOC_IF (regend, num_regs, re_char *);
2365 RETALLOC_IF (best_regstart, num_regs, re_char *);
2366 RETALLOC_IF (best_regend, num_regs, re_char *);
2368 regs_allocated_size = num_regs;
2372 #endif /* not MATCH_MAY_ALLOCATE */
2374 static boolean group_in_compile_stack (compile_stack_type compile_stack,
2375 regnum_t regnum);
2377 /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
2378 Returns one of error codes defined in `regex.h', or zero for success.
2380 Assumes the `allocated' (and perhaps `buffer') and `translate'
2381 fields are set in BUFP on entry.
2383 If it succeeds, results are put in BUFP (if it returns an error, the
2384 contents of BUFP are undefined):
2385 `buffer' is the compiled pattern;
2386 `syntax' is set to SYNTAX;
2387 `used' is set to the length of the compiled pattern;
2388 `fastmap_accurate' is zero;
2389 `re_nsub' is the number of subexpressions in PATTERN;
2390 `not_bol' and `not_eol' are zero;
2392 The `fastmap' field is neither examined nor set. */
2394 /* Insert the `jump' from the end of last alternative to "here".
2395 The space for the jump has already been allocated. */
2396 #define FIXUP_ALT_JUMP() \
2397 do { \
2398 if (fixup_alt_jump) \
2399 STORE_JUMP (jump, fixup_alt_jump, b); \
2400 } while (0)
2403 /* Return, freeing storage we allocated. */
2404 #define FREE_STACK_RETURN(value) \
2405 do { \
2406 FREE_RANGE_TABLE_WORK_AREA (range_table_work); \
2407 free (compile_stack.stack); \
2408 return value; \
2409 } while (0)
2411 static reg_errcode_t
2412 regex_compile (const re_char *pattern, size_t size, reg_syntax_t syntax, struct re_pattern_buffer *bufp)
2414 /* We fetch characters from PATTERN here. */
2415 register re_wchar_t c, c1;
2417 /* Points to the end of the buffer, where we should append. */
2418 register unsigned char *b;
2420 /* Keeps track of unclosed groups. */
2421 compile_stack_type compile_stack;
2423 /* Points to the current (ending) position in the pattern. */
2424 #ifdef AIX
2425 /* `const' makes AIX compiler fail. */
2426 unsigned char *p = pattern;
2427 #else
2428 re_char *p = pattern;
2429 #endif
2430 re_char *pend = pattern + size;
2432 /* How to translate the characters in the pattern. */
2433 RE_TRANSLATE_TYPE translate = bufp->translate;
2435 /* Address of the count-byte of the most recently inserted `exactn'
2436 command. This makes it possible to tell if a new exact-match
2437 character can be added to that command or if the character requires
2438 a new `exactn' command. */
2439 unsigned char *pending_exact = 0;
2441 /* Address of start of the most recently finished expression.
2442 This tells, e.g., postfix * where to find the start of its
2443 operand. Reset at the beginning of groups and alternatives. */
2444 unsigned char *laststart = 0;
2446 /* Address of beginning of regexp, or inside of last group. */
2447 unsigned char *begalt;
2449 /* Place in the uncompiled pattern (i.e., the {) to
2450 which to go back if the interval is invalid. */
2451 re_char *beg_interval;
2453 /* Address of the place where a forward jump should go to the end of
2454 the containing expression. Each alternative of an `or' -- except the
2455 last -- ends with a forward jump of this sort. */
2456 unsigned char *fixup_alt_jump = 0;
2458 /* Work area for range table of charset. */
2459 struct range_table_work_area range_table_work;
2461 /* If the object matched can contain multibyte characters. */
2462 const boolean multibyte = RE_MULTIBYTE_P (bufp);
2464 /* Nonzero if we have pushed down into a subpattern. */
2465 int in_subpattern = 0;
2467 /* These hold the values of p, pattern, and pend from the main
2468 pattern when we have pushed into a subpattern. */
2469 re_char *main_p IF_LINT (= NULL);
2470 re_char *main_pattern IF_LINT (= NULL);
2471 re_char *main_pend IF_LINT (= NULL);
2473 #ifdef DEBUG
2474 debug++;
2475 DEBUG_PRINT ("\nCompiling pattern: ");
2476 if (debug > 0)
2478 unsigned debug_count;
2480 for (debug_count = 0; debug_count < size; debug_count++)
2481 putchar (pattern[debug_count]);
2482 putchar ('\n');
2484 #endif /* DEBUG */
2486 /* Initialize the compile stack. */
2487 compile_stack.stack = TALLOC (INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
2488 if (compile_stack.stack == NULL)
2489 return REG_ESPACE;
2491 compile_stack.size = INIT_COMPILE_STACK_SIZE;
2492 compile_stack.avail = 0;
2494 range_table_work.table = 0;
2495 range_table_work.allocated = 0;
2497 /* Initialize the pattern buffer. */
2498 bufp->syntax = syntax;
2499 bufp->fastmap_accurate = 0;
2500 bufp->not_bol = bufp->not_eol = 0;
2501 bufp->used_syntax = 0;
2503 /* Set `used' to zero, so that if we return an error, the pattern
2504 printer (for debugging) will think there's no pattern. We reset it
2505 at the end. */
2506 bufp->used = 0;
2508 /* Always count groups, whether or not bufp->no_sub is set. */
2509 bufp->re_nsub = 0;
2511 #if !defined emacs && !defined SYNTAX_TABLE
2512 /* Initialize the syntax table. */
2513 init_syntax_once ();
2514 #endif
2516 if (bufp->allocated == 0)
2518 if (bufp->buffer)
2519 { /* If zero allocated, but buffer is non-null, try to realloc
2520 enough space. This loses if buffer's address is bogus, but
2521 that is the user's responsibility. */
2522 RETALLOC (bufp->buffer, INIT_BUF_SIZE, unsigned char);
2524 else
2525 { /* Caller did not allocate a buffer. Do it for them. */
2526 bufp->buffer = TALLOC (INIT_BUF_SIZE, unsigned char);
2528 if (!bufp->buffer) FREE_STACK_RETURN (REG_ESPACE);
2530 bufp->allocated = INIT_BUF_SIZE;
2533 begalt = b = bufp->buffer;
2535 /* Loop through the uncompiled pattern until we're at the end. */
2536 while (1)
2538 if (p == pend)
2540 /* If this is the end of an included regexp,
2541 pop back to the main regexp and try again. */
2542 if (in_subpattern)
2544 in_subpattern = 0;
2545 pattern = main_pattern;
2546 p = main_p;
2547 pend = main_pend;
2548 continue;
2550 /* If this is the end of the main regexp, we are done. */
2551 break;
2554 PATFETCH (c);
2556 switch (c)
2558 case ' ':
2560 re_char *p1 = p;
2562 /* If there's no special whitespace regexp, treat
2563 spaces normally. And don't try to do this recursively. */
2564 if (!whitespace_regexp || in_subpattern)
2565 goto normal_char;
2567 /* Peek past following spaces. */
2568 while (p1 != pend)
2570 if (*p1 != ' ')
2571 break;
2572 p1++;
2574 /* If the spaces are followed by a repetition op,
2575 treat them normally. */
2576 if (p1 != pend
2577 && (*p1 == '*' || *p1 == '+' || *p1 == '?'
2578 || (*p1 == '\\' && p1 + 1 != pend && p1[1] == '{')))
2579 goto normal_char;
2581 /* Replace the spaces with the whitespace regexp. */
2582 in_subpattern = 1;
2583 main_p = p1;
2584 main_pend = pend;
2585 main_pattern = pattern;
2586 p = pattern = whitespace_regexp;
2587 pend = p + strlen ((const char *) p);
2588 break;
2591 case '^':
2593 if ( /* If at start of pattern, it's an operator. */
2594 p == pattern + 1
2595 /* If context independent, it's an operator. */
2596 || syntax & RE_CONTEXT_INDEP_ANCHORS
2597 /* Otherwise, depends on what's come before. */
2598 || at_begline_loc_p (pattern, p, syntax))
2599 BUF_PUSH ((syntax & RE_NO_NEWLINE_ANCHOR) ? begbuf : begline);
2600 else
2601 goto normal_char;
2603 break;
2606 case '$':
2608 if ( /* If at end of pattern, it's an operator. */
2609 p == pend
2610 /* If context independent, it's an operator. */
2611 || syntax & RE_CONTEXT_INDEP_ANCHORS
2612 /* Otherwise, depends on what's next. */
2613 || at_endline_loc_p (p, pend, syntax))
2614 BUF_PUSH ((syntax & RE_NO_NEWLINE_ANCHOR) ? endbuf : endline);
2615 else
2616 goto normal_char;
2618 break;
2621 case '+':
2622 case '?':
2623 if ((syntax & RE_BK_PLUS_QM)
2624 || (syntax & RE_LIMITED_OPS))
2625 goto normal_char;
2626 handle_plus:
2627 case '*':
2628 /* If there is no previous pattern... */
2629 if (!laststart)
2631 if (syntax & RE_CONTEXT_INVALID_OPS)
2632 FREE_STACK_RETURN (REG_BADRPT);
2633 else if (!(syntax & RE_CONTEXT_INDEP_OPS))
2634 goto normal_char;
2638 /* 1 means zero (many) matches is allowed. */
2639 boolean zero_times_ok = 0, many_times_ok = 0;
2640 boolean greedy = 1;
2642 /* If there is a sequence of repetition chars, collapse it
2643 down to just one (the right one). We can't combine
2644 interval operators with these because of, e.g., `a{2}*',
2645 which should only match an even number of `a's. */
2647 for (;;)
2649 if ((syntax & RE_FRUGAL)
2650 && c == '?' && (zero_times_ok || many_times_ok))
2651 greedy = 0;
2652 else
2654 zero_times_ok |= c != '+';
2655 many_times_ok |= c != '?';
2658 if (p == pend)
2659 break;
2660 else if (*p == '*'
2661 || (!(syntax & RE_BK_PLUS_QM)
2662 && (*p == '+' || *p == '?')))
2664 else if (syntax & RE_BK_PLUS_QM && *p == '\\')
2666 if (p+1 == pend)
2667 FREE_STACK_RETURN (REG_EESCAPE);
2668 if (p[1] == '+' || p[1] == '?')
2669 PATFETCH (c); /* Gobble up the backslash. */
2670 else
2671 break;
2673 else
2674 break;
2675 /* If we get here, we found another repeat character. */
2676 PATFETCH (c);
2679 /* Star, etc. applied to an empty pattern is equivalent
2680 to an empty pattern. */
2681 if (!laststart || laststart == b)
2682 break;
2684 /* Now we know whether or not zero matches is allowed
2685 and also whether or not two or more matches is allowed. */
2686 if (greedy)
2688 if (many_times_ok)
2690 boolean simple = skip_one_char (laststart) == b;
2691 size_t startoffset = 0;
2692 re_opcode_t ofj =
2693 /* Check if the loop can match the empty string. */
2694 (simple || !analyse_first (laststart, b, NULL, 0))
2695 ? on_failure_jump : on_failure_jump_loop;
2696 assert (skip_one_char (laststart) <= b);
2698 if (!zero_times_ok && simple)
2699 { /* Since simple * loops can be made faster by using
2700 on_failure_keep_string_jump, we turn simple P+
2701 into PP* if P is simple. */
2702 unsigned char *p1, *p2;
2703 startoffset = b - laststart;
2704 GET_BUFFER_SPACE (startoffset);
2705 p1 = b; p2 = laststart;
2706 while (p2 < p1)
2707 *b++ = *p2++;
2708 zero_times_ok = 1;
2711 GET_BUFFER_SPACE (6);
2712 if (!zero_times_ok)
2713 /* A + loop. */
2714 STORE_JUMP (ofj, b, b + 6);
2715 else
2716 /* Simple * loops can use on_failure_keep_string_jump
2717 depending on what follows. But since we don't know
2718 that yet, we leave the decision up to
2719 on_failure_jump_smart. */
2720 INSERT_JUMP (simple ? on_failure_jump_smart : ofj,
2721 laststart + startoffset, b + 6);
2722 b += 3;
2723 STORE_JUMP (jump, b, laststart + startoffset);
2724 b += 3;
2726 else
2728 /* A simple ? pattern. */
2729 assert (zero_times_ok);
2730 GET_BUFFER_SPACE (3);
2731 INSERT_JUMP (on_failure_jump, laststart, b + 3);
2732 b += 3;
2735 else /* not greedy */
2736 { /* I wish the greedy and non-greedy cases could be merged. */
2738 GET_BUFFER_SPACE (7); /* We might use less. */
2739 if (many_times_ok)
2741 boolean emptyp = analyse_first (laststart, b, NULL, 0);
2743 /* The non-greedy multiple match looks like
2744 a repeat..until: we only need a conditional jump
2745 at the end of the loop. */
2746 if (emptyp) BUF_PUSH (no_op);
2747 STORE_JUMP (emptyp ? on_failure_jump_nastyloop
2748 : on_failure_jump, b, laststart);
2749 b += 3;
2750 if (zero_times_ok)
2752 /* The repeat...until naturally matches one or more.
2753 To also match zero times, we need to first jump to
2754 the end of the loop (its conditional jump). */
2755 INSERT_JUMP (jump, laststart, b);
2756 b += 3;
2759 else
2761 /* non-greedy a?? */
2762 INSERT_JUMP (jump, laststart, b + 3);
2763 b += 3;
2764 INSERT_JUMP (on_failure_jump, laststart, laststart + 6);
2765 b += 3;
2769 pending_exact = 0;
2770 break;
2773 case '.':
2774 laststart = b;
2775 BUF_PUSH (anychar);
2776 break;
2779 case '[':
2781 re_char *p1;
2783 CLEAR_RANGE_TABLE_WORK_USED (range_table_work);
2785 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2787 /* Ensure that we have enough space to push a charset: the
2788 opcode, the length count, and the bitset; 34 bytes in all. */
2789 GET_BUFFER_SPACE (34);
2791 laststart = b;
2793 /* We test `*p == '^' twice, instead of using an if
2794 statement, so we only need one BUF_PUSH. */
2795 BUF_PUSH (*p == '^' ? charset_not : charset);
2796 if (*p == '^')
2797 p++;
2799 /* Remember the first position in the bracket expression. */
2800 p1 = p;
2802 /* Push the number of bytes in the bitmap. */
2803 BUF_PUSH ((1 << BYTEWIDTH) / BYTEWIDTH);
2805 /* Clear the whole map. */
2806 memset (b, 0, (1 << BYTEWIDTH) / BYTEWIDTH);
2808 /* charset_not matches newline according to a syntax bit. */
2809 if ((re_opcode_t) b[-2] == charset_not
2810 && (syntax & RE_HAT_LISTS_NOT_NEWLINE))
2811 SET_LIST_BIT ('\n');
2813 /* Read in characters and ranges, setting map bits. */
2814 for (;;)
2816 boolean escaped_char = false;
2817 const unsigned char *p2 = p;
2818 re_wchar_t ch;
2820 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2822 /* Don't translate yet. The range TRANSLATE(X..Y) cannot
2823 always be determined from TRANSLATE(X) and TRANSLATE(Y)
2824 So the translation is done later in a loop. Example:
2825 (let ((case-fold-search t)) (string-match "[A-_]" "A")) */
2826 PATFETCH (c);
2828 /* \ might escape characters inside [...] and [^...]. */
2829 if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\')
2831 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2833 PATFETCH (c);
2834 escaped_char = true;
2836 else
2838 /* Could be the end of the bracket expression. If it's
2839 not (i.e., when the bracket expression is `[]' so
2840 far), the ']' character bit gets set way below. */
2841 if (c == ']' && p2 != p1)
2842 break;
2845 /* See if we're at the beginning of a possible character
2846 class. */
2848 if (!escaped_char &&
2849 syntax & RE_CHAR_CLASSES && c == '[' && *p == ':')
2851 /* Leave room for the null. */
2852 unsigned char str[CHAR_CLASS_MAX_LENGTH + 1];
2853 const unsigned char *class_beg;
2855 PATFETCH (c);
2856 c1 = 0;
2857 class_beg = p;
2859 /* If pattern is `[[:'. */
2860 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2862 for (;;)
2864 PATFETCH (c);
2865 if ((c == ':' && *p == ']') || p == pend)
2866 break;
2867 if (c1 < CHAR_CLASS_MAX_LENGTH)
2868 str[c1++] = c;
2869 else
2870 /* This is in any case an invalid class name. */
2871 str[0] = '\0';
2873 str[c1] = '\0';
2875 /* If isn't a word bracketed by `[:' and `:]':
2876 undo the ending character, the letters, and
2877 leave the leading `:' and `[' (but set bits for
2878 them). */
2879 if (c == ':' && *p == ']')
2881 re_wctype_t cc = re_wctype (str);
2883 if (cc == 0)
2884 FREE_STACK_RETURN (REG_ECTYPE);
2886 /* Throw away the ] at the end of the character
2887 class. */
2888 PATFETCH (c);
2890 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2892 #ifndef emacs
2893 for (ch = 0; ch < (1 << BYTEWIDTH); ++ch)
2894 if (re_iswctype (btowc (ch), cc))
2896 c = TRANSLATE (ch);
2897 if (c < (1 << BYTEWIDTH))
2898 SET_LIST_BIT (c);
2900 #else /* emacs */
2901 /* Most character classes in a multibyte match
2902 just set a flag. Exceptions are is_blank,
2903 is_digit, is_cntrl, and is_xdigit, since
2904 they can only match ASCII characters. We
2905 don't need to handle them for multibyte.
2906 They are distinguished by a negative wctype. */
2908 /* Setup the gl_state object to its buffer-defined
2909 value. This hardcodes the buffer-global
2910 syntax-table for ASCII chars, while the other chars
2911 will obey syntax-table properties. It's not ideal,
2912 but it's the way it's been done until now. */
2913 SETUP_BUFFER_SYNTAX_TABLE ();
2915 for (ch = 0; ch < 256; ++ch)
2917 c = RE_CHAR_TO_MULTIBYTE (ch);
2918 if (! CHAR_BYTE8_P (c)
2919 && re_iswctype (c, cc))
2921 SET_LIST_BIT (ch);
2922 c1 = TRANSLATE (c);
2923 if (c1 == c)
2924 continue;
2925 if (ASCII_CHAR_P (c1))
2926 SET_LIST_BIT (c1);
2927 else if ((c1 = RE_CHAR_TO_UNIBYTE (c1)) >= 0)
2928 SET_LIST_BIT (c1);
2931 SET_RANGE_TABLE_WORK_AREA_BIT
2932 (range_table_work, re_wctype_to_bit (cc));
2933 #endif /* emacs */
2934 /* In most cases the matching rule for char classes
2935 only uses the syntax table for multibyte chars,
2936 so that the content of the syntax-table it is not
2937 hardcoded in the range_table. SPACE and WORD are
2938 the two exceptions. */
2939 if ((1 << cc) & ((1 << RECC_SPACE) | (1 << RECC_WORD)))
2940 bufp->used_syntax = 1;
2942 /* Repeat the loop. */
2943 continue;
2945 else
2947 /* Go back to right after the "[:". */
2948 p = class_beg;
2949 SET_LIST_BIT ('[');
2951 /* Because the `:' may starts the range, we
2952 can't simply set bit and repeat the loop.
2953 Instead, just set it to C and handle below. */
2954 c = ':';
2958 if (p < pend && p[0] == '-' && p[1] != ']')
2961 /* Discard the `-'. */
2962 PATFETCH (c1);
2964 /* Fetch the character which ends the range. */
2965 PATFETCH (c1);
2966 #ifdef emacs
2967 if (CHAR_BYTE8_P (c1)
2968 && ! ASCII_CHAR_P (c) && ! CHAR_BYTE8_P (c))
2969 /* Treat the range from a multibyte character to
2970 raw-byte character as empty. */
2971 c = c1 + 1;
2972 #endif /* emacs */
2974 else
2975 /* Range from C to C. */
2976 c1 = c;
2978 if (c > c1)
2980 if (syntax & RE_NO_EMPTY_RANGES)
2981 FREE_STACK_RETURN (REG_ERANGEX);
2982 /* Else, repeat the loop. */
2984 else
2986 #ifndef emacs
2987 /* Set the range into bitmap */
2988 for (; c <= c1; c++)
2990 ch = TRANSLATE (c);
2991 if (ch < (1 << BYTEWIDTH))
2992 SET_LIST_BIT (ch);
2994 #else /* emacs */
2995 if (c < 128)
2997 ch = MIN (127, c1);
2998 SETUP_ASCII_RANGE (range_table_work, c, ch);
2999 c = ch + 1;
3000 if (CHAR_BYTE8_P (c1))
3001 c = BYTE8_TO_CHAR (128);
3003 if (c <= c1)
3005 if (CHAR_BYTE8_P (c))
3007 c = CHAR_TO_BYTE8 (c);
3008 c1 = CHAR_TO_BYTE8 (c1);
3009 for (; c <= c1; c++)
3010 SET_LIST_BIT (c);
3012 else if (multibyte)
3014 SETUP_MULTIBYTE_RANGE (range_table_work, c, c1);
3016 else
3018 SETUP_UNIBYTE_RANGE (range_table_work, c, c1);
3021 #endif /* emacs */
3025 /* Discard any (non)matching list bytes that are all 0 at the
3026 end of the map. Decrease the map-length byte too. */
3027 while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
3028 b[-1]--;
3029 b += b[-1];
3031 /* Build real range table from work area. */
3032 if (RANGE_TABLE_WORK_USED (range_table_work)
3033 || RANGE_TABLE_WORK_BITS (range_table_work))
3035 int i;
3036 int used = RANGE_TABLE_WORK_USED (range_table_work);
3038 /* Allocate space for COUNT + RANGE_TABLE. Needs two
3039 bytes for flags, two for COUNT, and three bytes for
3040 each character. */
3041 GET_BUFFER_SPACE (4 + used * 3);
3043 /* Indicate the existence of range table. */
3044 laststart[1] |= 0x80;
3046 /* Store the character class flag bits into the range table.
3047 If not in emacs, these flag bits are always 0. */
3048 *b++ = RANGE_TABLE_WORK_BITS (range_table_work) & 0xff;
3049 *b++ = RANGE_TABLE_WORK_BITS (range_table_work) >> 8;
3051 STORE_NUMBER_AND_INCR (b, used / 2);
3052 for (i = 0; i < used; i++)
3053 STORE_CHARACTER_AND_INCR
3054 (b, RANGE_TABLE_WORK_ELT (range_table_work, i));
3057 break;
3060 case '(':
3061 if (syntax & RE_NO_BK_PARENS)
3062 goto handle_open;
3063 else
3064 goto normal_char;
3067 case ')':
3068 if (syntax & RE_NO_BK_PARENS)
3069 goto handle_close;
3070 else
3071 goto normal_char;
3074 case '\n':
3075 if (syntax & RE_NEWLINE_ALT)
3076 goto handle_alt;
3077 else
3078 goto normal_char;
3081 case '|':
3082 if (syntax & RE_NO_BK_VBAR)
3083 goto handle_alt;
3084 else
3085 goto normal_char;
3088 case '{':
3089 if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
3090 goto handle_interval;
3091 else
3092 goto normal_char;
3095 case '\\':
3096 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
3098 /* Do not translate the character after the \, so that we can
3099 distinguish, e.g., \B from \b, even if we normally would
3100 translate, e.g., B to b. */
3101 PATFETCH (c);
3103 switch (c)
3105 case '(':
3106 if (syntax & RE_NO_BK_PARENS)
3107 goto normal_backslash;
3109 handle_open:
3111 int shy = 0;
3112 regnum_t regnum = 0;
3113 if (p+1 < pend)
3115 /* Look for a special (?...) construct */
3116 if ((syntax & RE_SHY_GROUPS) && *p == '?')
3118 PATFETCH (c); /* Gobble up the '?'. */
3119 while (!shy)
3121 PATFETCH (c);
3122 switch (c)
3124 case ':': shy = 1; break;
3125 case '0':
3126 /* An explicitly specified regnum must start
3127 with non-0. */
3128 if (regnum == 0)
3129 FREE_STACK_RETURN (REG_BADPAT);
3130 case '1': case '2': case '3': case '4':
3131 case '5': case '6': case '7': case '8': case '9':
3132 regnum = 10*regnum + (c - '0'); break;
3133 default:
3134 /* Only (?:...) is supported right now. */
3135 FREE_STACK_RETURN (REG_BADPAT);
3141 if (!shy)
3142 regnum = ++bufp->re_nsub;
3143 else if (regnum)
3144 { /* It's actually not shy, but explicitly numbered. */
3145 shy = 0;
3146 if (regnum > bufp->re_nsub)
3147 bufp->re_nsub = regnum;
3148 else if (regnum > bufp->re_nsub
3149 /* Ideally, we'd want to check that the specified
3150 group can't have matched (i.e. all subgroups
3151 using the same regnum are in other branches of
3152 OR patterns), but we don't currently keep track
3153 of enough info to do that easily. */
3154 || group_in_compile_stack (compile_stack, regnum))
3155 FREE_STACK_RETURN (REG_BADPAT);
3157 else
3158 /* It's really shy. */
3159 regnum = - bufp->re_nsub;
3161 if (COMPILE_STACK_FULL)
3163 RETALLOC (compile_stack.stack, compile_stack.size << 1,
3164 compile_stack_elt_t);
3165 if (compile_stack.stack == NULL) return REG_ESPACE;
3167 compile_stack.size <<= 1;
3170 /* These are the values to restore when we hit end of this
3171 group. They are all relative offsets, so that if the
3172 whole pattern moves because of realloc, they will still
3173 be valid. */
3174 COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
3175 COMPILE_STACK_TOP.fixup_alt_jump
3176 = fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
3177 COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
3178 COMPILE_STACK_TOP.regnum = regnum;
3180 /* Do not push a start_memory for groups beyond the last one
3181 we can represent in the compiled pattern. */
3182 if (regnum <= MAX_REGNUM && regnum > 0)
3183 BUF_PUSH_2 (start_memory, regnum);
3185 compile_stack.avail++;
3187 fixup_alt_jump = 0;
3188 laststart = 0;
3189 begalt = b;
3190 /* If we've reached MAX_REGNUM groups, then this open
3191 won't actually generate any code, so we'll have to
3192 clear pending_exact explicitly. */
3193 pending_exact = 0;
3194 break;
3197 case ')':
3198 if (syntax & RE_NO_BK_PARENS) goto normal_backslash;
3200 if (COMPILE_STACK_EMPTY)
3202 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
3203 goto normal_backslash;
3204 else
3205 FREE_STACK_RETURN (REG_ERPAREN);
3208 handle_close:
3209 FIXUP_ALT_JUMP ();
3211 /* See similar code for backslashed left paren above. */
3212 if (COMPILE_STACK_EMPTY)
3214 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
3215 goto normal_char;
3216 else
3217 FREE_STACK_RETURN (REG_ERPAREN);
3220 /* Since we just checked for an empty stack above, this
3221 ``can't happen''. */
3222 assert (compile_stack.avail != 0);
3224 /* We don't just want to restore into `regnum', because
3225 later groups should continue to be numbered higher,
3226 as in `(ab)c(de)' -- the second group is #2. */
3227 regnum_t regnum;
3229 compile_stack.avail--;
3230 begalt = bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
3231 fixup_alt_jump
3232 = COMPILE_STACK_TOP.fixup_alt_jump
3233 ? bufp->buffer + COMPILE_STACK_TOP.fixup_alt_jump - 1
3234 : 0;
3235 laststart = bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
3236 regnum = COMPILE_STACK_TOP.regnum;
3237 /* If we've reached MAX_REGNUM groups, then this open
3238 won't actually generate any code, so we'll have to
3239 clear pending_exact explicitly. */
3240 pending_exact = 0;
3242 /* We're at the end of the group, so now we know how many
3243 groups were inside this one. */
3244 if (regnum <= MAX_REGNUM && regnum > 0)
3245 BUF_PUSH_2 (stop_memory, regnum);
3247 break;
3250 case '|': /* `\|'. */
3251 if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
3252 goto normal_backslash;
3253 handle_alt:
3254 if (syntax & RE_LIMITED_OPS)
3255 goto normal_char;
3257 /* Insert before the previous alternative a jump which
3258 jumps to this alternative if the former fails. */
3259 GET_BUFFER_SPACE (3);
3260 INSERT_JUMP (on_failure_jump, begalt, b + 6);
3261 pending_exact = 0;
3262 b += 3;
3264 /* The alternative before this one has a jump after it
3265 which gets executed if it gets matched. Adjust that
3266 jump so it will jump to this alternative's analogous
3267 jump (put in below, which in turn will jump to the next
3268 (if any) alternative's such jump, etc.). The last such
3269 jump jumps to the correct final destination. A picture:
3270 _____ _____
3271 | | | |
3272 | v | v
3273 a | b | c
3275 If we are at `b', then fixup_alt_jump right now points to a
3276 three-byte space after `a'. We'll put in the jump, set
3277 fixup_alt_jump to right after `b', and leave behind three
3278 bytes which we'll fill in when we get to after `c'. */
3280 FIXUP_ALT_JUMP ();
3282 /* Mark and leave space for a jump after this alternative,
3283 to be filled in later either by next alternative or
3284 when know we're at the end of a series of alternatives. */
3285 fixup_alt_jump = b;
3286 GET_BUFFER_SPACE (3);
3287 b += 3;
3289 laststart = 0;
3290 begalt = b;
3291 break;
3294 case '{':
3295 /* If \{ is a literal. */
3296 if (!(syntax & RE_INTERVALS)
3297 /* If we're at `\{' and it's not the open-interval
3298 operator. */
3299 || (syntax & RE_NO_BK_BRACES))
3300 goto normal_backslash;
3302 handle_interval:
3304 /* If got here, then the syntax allows intervals. */
3306 /* At least (most) this many matches must be made. */
3307 int lower_bound = 0, upper_bound = -1;
3309 beg_interval = p;
3311 GET_UNSIGNED_NUMBER (lower_bound);
3313 if (c == ',')
3314 GET_UNSIGNED_NUMBER (upper_bound);
3315 else
3316 /* Interval such as `{1}' => match exactly once. */
3317 upper_bound = lower_bound;
3319 if (lower_bound < 0 || upper_bound > RE_DUP_MAX
3320 || (upper_bound >= 0 && lower_bound > upper_bound))
3321 FREE_STACK_RETURN (REG_BADBR);
3323 if (!(syntax & RE_NO_BK_BRACES))
3325 if (c != '\\')
3326 FREE_STACK_RETURN (REG_BADBR);
3327 if (p == pend)
3328 FREE_STACK_RETURN (REG_EESCAPE);
3329 PATFETCH (c);
3332 if (c != '}')
3333 FREE_STACK_RETURN (REG_BADBR);
3335 /* We just parsed a valid interval. */
3337 /* If it's invalid to have no preceding re. */
3338 if (!laststart)
3340 if (syntax & RE_CONTEXT_INVALID_OPS)
3341 FREE_STACK_RETURN (REG_BADRPT);
3342 else if (syntax & RE_CONTEXT_INDEP_OPS)
3343 laststart = b;
3344 else
3345 goto unfetch_interval;
3348 if (upper_bound == 0)
3349 /* If the upper bound is zero, just drop the sub pattern
3350 altogether. */
3351 b = laststart;
3352 else if (lower_bound == 1 && upper_bound == 1)
3353 /* Just match it once: nothing to do here. */
3356 /* Otherwise, we have a nontrivial interval. When
3357 we're all done, the pattern will look like:
3358 set_number_at <jump count> <upper bound>
3359 set_number_at <succeed_n count> <lower bound>
3360 succeed_n <after jump addr> <succeed_n count>
3361 <body of loop>
3362 jump_n <succeed_n addr> <jump count>
3363 (The upper bound and `jump_n' are omitted if
3364 `upper_bound' is 1, though.) */
3365 else
3366 { /* If the upper bound is > 1, we need to insert
3367 more at the end of the loop. */
3368 unsigned int nbytes = (upper_bound < 0 ? 3
3369 : upper_bound > 1 ? 5 : 0);
3370 unsigned int startoffset = 0;
3372 GET_BUFFER_SPACE (20); /* We might use less. */
3374 if (lower_bound == 0)
3376 /* A succeed_n that starts with 0 is really a
3377 a simple on_failure_jump_loop. */
3378 INSERT_JUMP (on_failure_jump_loop, laststart,
3379 b + 3 + nbytes);
3380 b += 3;
3382 else
3384 /* Initialize lower bound of the `succeed_n', even
3385 though it will be set during matching by its
3386 attendant `set_number_at' (inserted next),
3387 because `re_compile_fastmap' needs to know.
3388 Jump to the `jump_n' we might insert below. */
3389 INSERT_JUMP2 (succeed_n, laststart,
3390 b + 5 + nbytes,
3391 lower_bound);
3392 b += 5;
3394 /* Code to initialize the lower bound. Insert
3395 before the `succeed_n'. The `5' is the last two
3396 bytes of this `set_number_at', plus 3 bytes of
3397 the following `succeed_n'. */
3398 insert_op2 (set_number_at, laststart, 5, lower_bound, b);
3399 b += 5;
3400 startoffset += 5;
3403 if (upper_bound < 0)
3405 /* A negative upper bound stands for infinity,
3406 in which case it degenerates to a plain jump. */
3407 STORE_JUMP (jump, b, laststart + startoffset);
3408 b += 3;
3410 else if (upper_bound > 1)
3411 { /* More than one repetition is allowed, so
3412 append a backward jump to the `succeed_n'
3413 that starts this interval.
3415 When we've reached this during matching,
3416 we'll have matched the interval once, so
3417 jump back only `upper_bound - 1' times. */
3418 STORE_JUMP2 (jump_n, b, laststart + startoffset,
3419 upper_bound - 1);
3420 b += 5;
3422 /* The location we want to set is the second
3423 parameter of the `jump_n'; that is `b-2' as
3424 an absolute address. `laststart' will be
3425 the `set_number_at' we're about to insert;
3426 `laststart+3' the number to set, the source
3427 for the relative address. But we are
3428 inserting into the middle of the pattern --
3429 so everything is getting moved up by 5.
3430 Conclusion: (b - 2) - (laststart + 3) + 5,
3431 i.e., b - laststart.
3433 We insert this at the beginning of the loop
3434 so that if we fail during matching, we'll
3435 reinitialize the bounds. */
3436 insert_op2 (set_number_at, laststart, b - laststart,
3437 upper_bound - 1, b);
3438 b += 5;
3441 pending_exact = 0;
3442 beg_interval = NULL;
3444 break;
3446 unfetch_interval:
3447 /* If an invalid interval, match the characters as literals. */
3448 assert (beg_interval);
3449 p = beg_interval;
3450 beg_interval = NULL;
3452 /* normal_char and normal_backslash need `c'. */
3453 c = '{';
3455 if (!(syntax & RE_NO_BK_BRACES))
3457 assert (p > pattern && p[-1] == '\\');
3458 goto normal_backslash;
3460 else
3461 goto normal_char;
3463 #ifdef emacs
3464 /* There is no way to specify the before_dot and after_dot
3465 operators. rms says this is ok. --karl */
3466 case '=':
3467 laststart = b;
3468 BUF_PUSH (at_dot);
3469 break;
3471 case 's':
3472 laststart = b;
3473 PATFETCH (c);
3474 BUF_PUSH_2 (syntaxspec, syntax_spec_code[c]);
3475 break;
3477 case 'S':
3478 laststart = b;
3479 PATFETCH (c);
3480 BUF_PUSH_2 (notsyntaxspec, syntax_spec_code[c]);
3481 break;
3483 case 'c':
3484 laststart = b;
3485 PATFETCH (c);
3486 BUF_PUSH_2 (categoryspec, c);
3487 break;
3489 case 'C':
3490 laststart = b;
3491 PATFETCH (c);
3492 BUF_PUSH_2 (notcategoryspec, c);
3493 break;
3494 #endif /* emacs */
3497 case 'w':
3498 if (syntax & RE_NO_GNU_OPS)
3499 goto normal_char;
3500 laststart = b;
3501 BUF_PUSH_2 (syntaxspec, Sword);
3502 break;
3505 case 'W':
3506 if (syntax & RE_NO_GNU_OPS)
3507 goto normal_char;
3508 laststart = b;
3509 BUF_PUSH_2 (notsyntaxspec, Sword);
3510 break;
3513 case '<':
3514 if (syntax & RE_NO_GNU_OPS)
3515 goto normal_char;
3516 laststart = b;
3517 BUF_PUSH (wordbeg);
3518 break;
3520 case '>':
3521 if (syntax & RE_NO_GNU_OPS)
3522 goto normal_char;
3523 laststart = b;
3524 BUF_PUSH (wordend);
3525 break;
3527 case '_':
3528 if (syntax & RE_NO_GNU_OPS)
3529 goto normal_char;
3530 laststart = b;
3531 PATFETCH (c);
3532 if (c == '<')
3533 BUF_PUSH (symbeg);
3534 else if (c == '>')
3535 BUF_PUSH (symend);
3536 else
3537 FREE_STACK_RETURN (REG_BADPAT);
3538 break;
3540 case 'b':
3541 if (syntax & RE_NO_GNU_OPS)
3542 goto normal_char;
3543 BUF_PUSH (wordbound);
3544 break;
3546 case 'B':
3547 if (syntax & RE_NO_GNU_OPS)
3548 goto normal_char;
3549 BUF_PUSH (notwordbound);
3550 break;
3552 case '`':
3553 if (syntax & RE_NO_GNU_OPS)
3554 goto normal_char;
3555 BUF_PUSH (begbuf);
3556 break;
3558 case '\'':
3559 if (syntax & RE_NO_GNU_OPS)
3560 goto normal_char;
3561 BUF_PUSH (endbuf);
3562 break;
3564 case '1': case '2': case '3': case '4': case '5':
3565 case '6': case '7': case '8': case '9':
3567 regnum_t reg;
3569 if (syntax & RE_NO_BK_REFS)
3570 goto normal_backslash;
3572 reg = c - '0';
3574 if (reg > bufp->re_nsub || reg < 1
3575 /* Can't back reference to a subexp before its end. */
3576 || group_in_compile_stack (compile_stack, reg))
3577 FREE_STACK_RETURN (REG_ESUBREG);
3579 laststart = b;
3580 BUF_PUSH_2 (duplicate, reg);
3582 break;
3585 case '+':
3586 case '?':
3587 if (syntax & RE_BK_PLUS_QM)
3588 goto handle_plus;
3589 else
3590 goto normal_backslash;
3592 default:
3593 normal_backslash:
3594 /* You might think it would be useful for \ to mean
3595 not to translate; but if we don't translate it
3596 it will never match anything. */
3597 goto normal_char;
3599 break;
3602 default:
3603 /* Expects the character in `c'. */
3604 normal_char:
3605 /* If no exactn currently being built. */
3606 if (!pending_exact
3608 /* If last exactn not at current position. */
3609 || pending_exact + *pending_exact + 1 != b
3611 /* We have only one byte following the exactn for the count. */
3612 || *pending_exact >= (1 << BYTEWIDTH) - MAX_MULTIBYTE_LENGTH
3614 /* If followed by a repetition operator. */
3615 || (p != pend && (*p == '*' || *p == '^'))
3616 || ((syntax & RE_BK_PLUS_QM)
3617 ? p + 1 < pend && *p == '\\' && (p[1] == '+' || p[1] == '?')
3618 : p != pend && (*p == '+' || *p == '?'))
3619 || ((syntax & RE_INTERVALS)
3620 && ((syntax & RE_NO_BK_BRACES)
3621 ? p != pend && *p == '{'
3622 : p + 1 < pend && p[0] == '\\' && p[1] == '{')))
3624 /* Start building a new exactn. */
3626 laststart = b;
3628 BUF_PUSH_2 (exactn, 0);
3629 pending_exact = b - 1;
3632 GET_BUFFER_SPACE (MAX_MULTIBYTE_LENGTH);
3634 int len;
3636 if (multibyte)
3638 c = TRANSLATE (c);
3639 len = CHAR_STRING (c, b);
3640 b += len;
3642 else
3644 c1 = RE_CHAR_TO_MULTIBYTE (c);
3645 if (! CHAR_BYTE8_P (c1))
3647 re_wchar_t c2 = TRANSLATE (c1);
3649 if (c1 != c2 && (c1 = RE_CHAR_TO_UNIBYTE (c2)) >= 0)
3650 c = c1;
3652 *b++ = c;
3653 len = 1;
3655 (*pending_exact) += len;
3658 break;
3659 } /* switch (c) */
3660 } /* while p != pend */
3663 /* Through the pattern now. */
3665 FIXUP_ALT_JUMP ();
3667 if (!COMPILE_STACK_EMPTY)
3668 FREE_STACK_RETURN (REG_EPAREN);
3670 /* If we don't want backtracking, force success
3671 the first time we reach the end of the compiled pattern. */
3672 if (syntax & RE_NO_POSIX_BACKTRACKING)
3673 BUF_PUSH (succeed);
3675 /* We have succeeded; set the length of the buffer. */
3676 bufp->used = b - bufp->buffer;
3678 #ifdef DEBUG
3679 if (debug > 0)
3681 re_compile_fastmap (bufp);
3682 DEBUG_PRINT ("\nCompiled pattern: \n");
3683 print_compiled_pattern (bufp);
3685 debug--;
3686 #endif /* DEBUG */
3688 #ifndef MATCH_MAY_ALLOCATE
3689 /* Initialize the failure stack to the largest possible stack. This
3690 isn't necessary unless we're trying to avoid calling alloca in
3691 the search and match routines. */
3693 int num_regs = bufp->re_nsub + 1;
3695 if (fail_stack.size < re_max_failures * TYPICAL_FAILURE_SIZE)
3697 fail_stack.size = re_max_failures * TYPICAL_FAILURE_SIZE;
3698 falk_stack.stack = realloc (fail_stack.stack,
3699 fail_stack.size * sizeof *falk_stack.stack);
3702 regex_grow_registers (num_regs);
3704 #endif /* not MATCH_MAY_ALLOCATE */
3706 FREE_STACK_RETURN (REG_NOERROR);
3707 } /* regex_compile */
3709 /* Subroutines for `regex_compile'. */
3711 /* Store OP at LOC followed by two-byte integer parameter ARG. */
3713 static void
3714 store_op1 (re_opcode_t op, unsigned char *loc, int arg)
3716 *loc = (unsigned char) op;
3717 STORE_NUMBER (loc + 1, arg);
3721 /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
3723 static void
3724 store_op2 (re_opcode_t op, unsigned char *loc, int arg1, int arg2)
3726 *loc = (unsigned char) op;
3727 STORE_NUMBER (loc + 1, arg1);
3728 STORE_NUMBER (loc + 3, arg2);
3732 /* Copy the bytes from LOC to END to open up three bytes of space at LOC
3733 for OP followed by two-byte integer parameter ARG. */
3735 static void
3736 insert_op1 (re_opcode_t op, unsigned char *loc, int arg, unsigned char *end)
3738 register unsigned char *pfrom = end;
3739 register unsigned char *pto = end + 3;
3741 while (pfrom != loc)
3742 *--pto = *--pfrom;
3744 store_op1 (op, loc, arg);
3748 /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
3750 static void
3751 insert_op2 (re_opcode_t op, unsigned char *loc, int arg1, int arg2, unsigned char *end)
3753 register unsigned char *pfrom = end;
3754 register unsigned char *pto = end + 5;
3756 while (pfrom != loc)
3757 *--pto = *--pfrom;
3759 store_op2 (op, loc, arg1, arg2);
3763 /* P points to just after a ^ in PATTERN. Return true if that ^ comes
3764 after an alternative or a begin-subexpression. We assume there is at
3765 least one character before the ^. */
3767 static boolean
3768 at_begline_loc_p (const re_char *pattern, const re_char *p, reg_syntax_t syntax)
3770 re_char *prev = p - 2;
3771 boolean odd_backslashes;
3773 /* After a subexpression? */
3774 if (*prev == '(')
3775 odd_backslashes = (syntax & RE_NO_BK_PARENS) == 0;
3777 /* After an alternative? */
3778 else if (*prev == '|')
3779 odd_backslashes = (syntax & RE_NO_BK_VBAR) == 0;
3781 /* After a shy subexpression? */
3782 else if (*prev == ':' && (syntax & RE_SHY_GROUPS))
3784 /* Skip over optional regnum. */
3785 while (prev - 1 >= pattern && prev[-1] >= '0' && prev[-1] <= '9')
3786 --prev;
3788 if (!(prev - 2 >= pattern
3789 && prev[-1] == '?' && prev[-2] == '('))
3790 return false;
3791 prev -= 2;
3792 odd_backslashes = (syntax & RE_NO_BK_PARENS) == 0;
3794 else
3795 return false;
3797 /* Count the number of preceding backslashes. */
3798 p = prev;
3799 while (prev - 1 >= pattern && prev[-1] == '\\')
3800 --prev;
3801 return (p - prev) & odd_backslashes;
3805 /* The dual of at_begline_loc_p. This one is for $. We assume there is
3806 at least one character after the $, i.e., `P < PEND'. */
3808 static boolean
3809 at_endline_loc_p (const re_char *p, const re_char *pend, reg_syntax_t syntax)
3811 re_char *next = p;
3812 boolean next_backslash = *next == '\\';
3813 re_char *next_next = p + 1 < pend ? p + 1 : 0;
3815 return
3816 /* Before a subexpression? */
3817 (syntax & RE_NO_BK_PARENS ? *next == ')'
3818 : next_backslash && next_next && *next_next == ')')
3819 /* Before an alternative? */
3820 || (syntax & RE_NO_BK_VBAR ? *next == '|'
3821 : next_backslash && next_next && *next_next == '|');
3825 /* Returns true if REGNUM is in one of COMPILE_STACK's elements and
3826 false if it's not. */
3828 static boolean
3829 group_in_compile_stack (compile_stack_type compile_stack, regnum_t regnum)
3831 ssize_t this_element;
3833 for (this_element = compile_stack.avail - 1;
3834 this_element >= 0;
3835 this_element--)
3836 if (compile_stack.stack[this_element].regnum == regnum)
3837 return true;
3839 return false;
3842 /* analyse_first.
3843 If fastmap is non-NULL, go through the pattern and fill fastmap
3844 with all the possible leading chars. If fastmap is NULL, don't
3845 bother filling it up (obviously) and only return whether the
3846 pattern could potentially match the empty string.
3848 Return 1 if p..pend might match the empty string.
3849 Return 0 if p..pend matches at least one char.
3850 Return -1 if fastmap was not updated accurately. */
3852 static int
3853 analyse_first (const re_char *p, const re_char *pend, char *fastmap, const int multibyte)
3855 int j, k;
3856 boolean not;
3858 /* If all elements for base leading-codes in fastmap is set, this
3859 flag is set true. */
3860 boolean match_any_multibyte_characters = false;
3862 assert (p);
3864 /* The loop below works as follows:
3865 - It has a working-list kept in the PATTERN_STACK and which basically
3866 starts by only containing a pointer to the first operation.
3867 - If the opcode we're looking at is a match against some set of
3868 chars, then we add those chars to the fastmap and go on to the
3869 next work element from the worklist (done via `break').
3870 - If the opcode is a control operator on the other hand, we either
3871 ignore it (if it's meaningless at this point, such as `start_memory')
3872 or execute it (if it's a jump). If the jump has several destinations
3873 (i.e. `on_failure_jump'), then we push the other destination onto the
3874 worklist.
3875 We guarantee termination by ignoring backward jumps (more or less),
3876 so that `p' is monotonically increasing. More to the point, we
3877 never set `p' (or push) anything `<= p1'. */
3879 while (p < pend)
3881 /* `p1' is used as a marker of how far back a `on_failure_jump'
3882 can go without being ignored. It is normally equal to `p'
3883 (which prevents any backward `on_failure_jump') except right
3884 after a plain `jump', to allow patterns such as:
3885 0: jump 10
3886 3..9: <body>
3887 10: on_failure_jump 3
3888 as used for the *? operator. */
3889 re_char *p1 = p;
3891 switch (*p++)
3893 case succeed:
3894 return 1;
3896 case duplicate:
3897 /* If the first character has to match a backreference, that means
3898 that the group was empty (since it already matched). Since this
3899 is the only case that interests us here, we can assume that the
3900 backreference must match the empty string. */
3901 p++;
3902 continue;
3905 /* Following are the cases which match a character. These end
3906 with `break'. */
3908 case exactn:
3909 if (fastmap)
3911 /* If multibyte is nonzero, the first byte of each
3912 character is an ASCII or a leading code. Otherwise,
3913 each byte is a character. Thus, this works in both
3914 cases. */
3915 fastmap[p[1]] = 1;
3916 if (! multibyte)
3918 /* For the case of matching this unibyte regex
3919 against multibyte, we must set a leading code of
3920 the corresponding multibyte character. */
3921 int c = RE_CHAR_TO_MULTIBYTE (p[1]);
3923 fastmap[CHAR_LEADING_CODE (c)] = 1;
3926 break;
3929 case anychar:
3930 /* We could put all the chars except for \n (and maybe \0)
3931 but we don't bother since it is generally not worth it. */
3932 if (!fastmap) break;
3933 return -1;
3936 case charset_not:
3937 if (!fastmap) break;
3939 /* Chars beyond end of bitmap are possible matches. */
3940 for (j = CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH;
3941 j < (1 << BYTEWIDTH); j++)
3942 fastmap[j] = 1;
3945 /* Fallthrough */
3946 case charset:
3947 if (!fastmap) break;
3948 not = (re_opcode_t) *(p - 1) == charset_not;
3949 for (j = CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH - 1, p++;
3950 j >= 0; j--)
3951 if (!!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))) ^ not)
3952 fastmap[j] = 1;
3954 #ifdef emacs
3955 if (/* Any leading code can possibly start a character
3956 which doesn't match the specified set of characters. */
3959 /* If we can match a character class, we can match any
3960 multibyte characters. */
3961 (CHARSET_RANGE_TABLE_EXISTS_P (&p[-2])
3962 && CHARSET_RANGE_TABLE_BITS (&p[-2]) != 0))
3965 if (match_any_multibyte_characters == false)
3967 for (j = MIN_MULTIBYTE_LEADING_CODE;
3968 j <= MAX_MULTIBYTE_LEADING_CODE; j++)
3969 fastmap[j] = 1;
3970 match_any_multibyte_characters = true;
3974 else if (!not && CHARSET_RANGE_TABLE_EXISTS_P (&p[-2])
3975 && match_any_multibyte_characters == false)
3977 /* Set fastmap[I] to 1 where I is a leading code of each
3978 multibyte character in the range table. */
3979 int c, count;
3980 unsigned char lc1, lc2;
3982 /* Make P points the range table. `+ 2' is to skip flag
3983 bits for a character class. */
3984 p += CHARSET_BITMAP_SIZE (&p[-2]) + 2;
3986 /* Extract the number of ranges in range table into COUNT. */
3987 EXTRACT_NUMBER_AND_INCR (count, p);
3988 for (; count > 0; count--, p += 3)
3990 /* Extract the start and end of each range. */
3991 EXTRACT_CHARACTER (c, p);
3992 lc1 = CHAR_LEADING_CODE (c);
3993 p += 3;
3994 EXTRACT_CHARACTER (c, p);
3995 lc2 = CHAR_LEADING_CODE (c);
3996 for (j = lc1; j <= lc2; j++)
3997 fastmap[j] = 1;
4000 #endif
4001 break;
4003 case syntaxspec:
4004 case notsyntaxspec:
4005 if (!fastmap) break;
4006 #ifndef emacs
4007 not = (re_opcode_t)p[-1] == notsyntaxspec;
4008 k = *p++;
4009 for (j = 0; j < (1 << BYTEWIDTH); j++)
4010 if ((SYNTAX (j) == (enum syntaxcode) k) ^ not)
4011 fastmap[j] = 1;
4012 break;
4013 #else /* emacs */
4014 /* This match depends on text properties. These end with
4015 aborting optimizations. */
4016 return -1;
4018 case categoryspec:
4019 case notcategoryspec:
4020 if (!fastmap) break;
4021 not = (re_opcode_t)p[-1] == notcategoryspec;
4022 k = *p++;
4023 for (j = (1 << BYTEWIDTH); j >= 0; j--)
4024 if ((CHAR_HAS_CATEGORY (j, k)) ^ not)
4025 fastmap[j] = 1;
4027 /* Any leading code can possibly start a character which
4028 has or doesn't has the specified category. */
4029 if (match_any_multibyte_characters == false)
4031 for (j = MIN_MULTIBYTE_LEADING_CODE;
4032 j <= MAX_MULTIBYTE_LEADING_CODE; j++)
4033 fastmap[j] = 1;
4034 match_any_multibyte_characters = true;
4036 break;
4038 /* All cases after this match the empty string. These end with
4039 `continue'. */
4041 case before_dot:
4042 case at_dot:
4043 case after_dot:
4044 #endif /* !emacs */
4045 case no_op:
4046 case begline:
4047 case endline:
4048 case begbuf:
4049 case endbuf:
4050 case wordbound:
4051 case notwordbound:
4052 case wordbeg:
4053 case wordend:
4054 case symbeg:
4055 case symend:
4056 continue;
4059 case jump:
4060 EXTRACT_NUMBER_AND_INCR (j, p);
4061 if (j < 0)
4062 /* Backward jumps can only go back to code that we've already
4063 visited. `re_compile' should make sure this is true. */
4064 break;
4065 p += j;
4066 switch (*p)
4068 case on_failure_jump:
4069 case on_failure_keep_string_jump:
4070 case on_failure_jump_loop:
4071 case on_failure_jump_nastyloop:
4072 case on_failure_jump_smart:
4073 p++;
4074 break;
4075 default:
4076 continue;
4078 /* Keep `p1' to allow the `on_failure_jump' we are jumping to
4079 to jump back to "just after here". */
4080 /* Fallthrough */
4082 case on_failure_jump:
4083 case on_failure_keep_string_jump:
4084 case on_failure_jump_nastyloop:
4085 case on_failure_jump_loop:
4086 case on_failure_jump_smart:
4087 EXTRACT_NUMBER_AND_INCR (j, p);
4088 if (p + j <= p1)
4089 ; /* Backward jump to be ignored. */
4090 else
4091 { /* We have to look down both arms.
4092 We first go down the "straight" path so as to minimize
4093 stack usage when going through alternatives. */
4094 int r = analyse_first (p, pend, fastmap, multibyte);
4095 if (r) return r;
4096 p += j;
4098 continue;
4101 case jump_n:
4102 /* This code simply does not properly handle forward jump_n. */
4103 DEBUG_STATEMENT (EXTRACT_NUMBER (j, p); assert (j < 0));
4104 p += 4;
4105 /* jump_n can either jump or fall through. The (backward) jump
4106 case has already been handled, so we only need to look at the
4107 fallthrough case. */
4108 continue;
4110 case succeed_n:
4111 /* If N == 0, it should be an on_failure_jump_loop instead. */
4112 DEBUG_STATEMENT (EXTRACT_NUMBER (j, p + 2); assert (j > 0));
4113 p += 4;
4114 /* We only care about one iteration of the loop, so we don't
4115 need to consider the case where this behaves like an
4116 on_failure_jump. */
4117 continue;
4120 case set_number_at:
4121 p += 4;
4122 continue;
4125 case start_memory:
4126 case stop_memory:
4127 p += 1;
4128 continue;
4131 default:
4132 abort (); /* We have listed all the cases. */
4133 } /* switch *p++ */
4135 /* Getting here means we have found the possible starting
4136 characters for one path of the pattern -- and that the empty
4137 string does not match. We need not follow this path further. */
4138 return 0;
4139 } /* while p */
4141 /* We reached the end without matching anything. */
4142 return 1;
4144 } /* analyse_first */
4146 /* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
4147 BUFP. A fastmap records which of the (1 << BYTEWIDTH) possible
4148 characters can start a string that matches the pattern. This fastmap
4149 is used by re_search to skip quickly over impossible starting points.
4151 Character codes above (1 << BYTEWIDTH) are not represented in the
4152 fastmap, but the leading codes are represented. Thus, the fastmap
4153 indicates which character sets could start a match.
4155 The caller must supply the address of a (1 << BYTEWIDTH)-byte data
4156 area as BUFP->fastmap.
4158 We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
4159 the pattern buffer.
4161 Returns 0 if we succeed, -2 if an internal error. */
4164 re_compile_fastmap (struct re_pattern_buffer *bufp)
4166 char *fastmap = bufp->fastmap;
4167 int analysis;
4169 assert (fastmap && bufp->buffer);
4171 memset (fastmap, 0, 1 << BYTEWIDTH); /* Assume nothing's valid. */
4172 bufp->fastmap_accurate = 1; /* It will be when we're done. */
4174 analysis = analyse_first (bufp->buffer, bufp->buffer + bufp->used,
4175 fastmap, RE_MULTIBYTE_P (bufp));
4176 bufp->can_be_null = (analysis != 0);
4177 return 0;
4178 } /* re_compile_fastmap */
4180 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
4181 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
4182 this memory for recording register information. STARTS and ENDS
4183 must be allocated using the malloc library routine, and must each
4184 be at least NUM_REGS * sizeof (regoff_t) bytes long.
4186 If NUM_REGS == 0, then subsequent matches should allocate their own
4187 register data.
4189 Unless this function is called, the first search or match using
4190 PATTERN_BUFFER will allocate its own register data, without
4191 freeing the old data. */
4193 void
4194 re_set_registers (struct re_pattern_buffer *bufp, struct re_registers *regs, unsigned int num_regs, regoff_t *starts, regoff_t *ends)
4196 if (num_regs)
4198 bufp->regs_allocated = REGS_REALLOCATE;
4199 regs->num_regs = num_regs;
4200 regs->start = starts;
4201 regs->end = ends;
4203 else
4205 bufp->regs_allocated = REGS_UNALLOCATED;
4206 regs->num_regs = 0;
4207 regs->start = regs->end = (regoff_t *) 0;
4210 WEAK_ALIAS (__re_set_registers, re_set_registers)
4212 /* Searching routines. */
4214 /* Like re_search_2, below, but only one string is specified, and
4215 doesn't let you say where to stop matching. */
4217 regoff_t
4218 re_search (struct re_pattern_buffer *bufp, const char *string, size_t size,
4219 ssize_t startpos, ssize_t range, struct re_registers *regs)
4221 return re_search_2 (bufp, NULL, 0, string, size, startpos, range,
4222 regs, size);
4224 WEAK_ALIAS (__re_search, re_search)
4226 /* Head address of virtual concatenation of string. */
4227 #define HEAD_ADDR_VSTRING(P) \
4228 (((P) >= size1 ? string2 : string1))
4230 /* Address of POS in the concatenation of virtual string. */
4231 #define POS_ADDR_VSTRING(POS) \
4232 (((POS) >= size1 ? string2 - size1 : string1) + (POS))
4234 /* Using the compiled pattern in BUFP->buffer, first tries to match the
4235 virtual concatenation of STRING1 and STRING2, starting first at index
4236 STARTPOS, then at STARTPOS + 1, and so on.
4238 STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
4240 RANGE is how far to scan while trying to match. RANGE = 0 means try
4241 only at STARTPOS; in general, the last start tried is STARTPOS +
4242 RANGE.
4244 In REGS, return the indices of the virtual concatenation of STRING1
4245 and STRING2 that matched the entire BUFP->buffer and its contained
4246 subexpressions.
4248 Do not consider matching one past the index STOP in the virtual
4249 concatenation of STRING1 and STRING2.
4251 We return either the position in the strings at which the match was
4252 found, -1 if no match, or -2 if error (such as failure
4253 stack overflow). */
4255 regoff_t
4256 re_search_2 (struct re_pattern_buffer *bufp, const char *str1, size_t size1,
4257 const char *str2, size_t size2, ssize_t startpos, ssize_t range,
4258 struct re_registers *regs, ssize_t stop)
4260 regoff_t val;
4261 re_char *string1 = (re_char*) str1;
4262 re_char *string2 = (re_char*) str2;
4263 register char *fastmap = bufp->fastmap;
4264 register RE_TRANSLATE_TYPE translate = bufp->translate;
4265 size_t total_size = size1 + size2;
4266 ssize_t endpos = startpos + range;
4267 boolean anchored_start;
4268 /* Nonzero if we are searching multibyte string. */
4269 const boolean multibyte = RE_TARGET_MULTIBYTE_P (bufp);
4271 /* Check for out-of-range STARTPOS. */
4272 if (startpos < 0 || startpos > total_size)
4273 return -1;
4275 /* Fix up RANGE if it might eventually take us outside
4276 the virtual concatenation of STRING1 and STRING2.
4277 Make sure we won't move STARTPOS below 0 or above TOTAL_SIZE. */
4278 if (endpos < 0)
4279 range = 0 - startpos;
4280 else if (endpos > total_size)
4281 range = total_size - startpos;
4283 /* If the search isn't to be a backwards one, don't waste time in a
4284 search for a pattern anchored at beginning of buffer. */
4285 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == begbuf && range > 0)
4287 if (startpos > 0)
4288 return -1;
4289 else
4290 range = 0;
4293 #ifdef emacs
4294 /* In a forward search for something that starts with \=.
4295 don't keep searching past point. */
4296 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == at_dot && range > 0)
4298 range = PT_BYTE - BEGV_BYTE - startpos;
4299 if (range < 0)
4300 return -1;
4302 #endif /* emacs */
4304 /* Update the fastmap now if not correct already. */
4305 if (fastmap && !bufp->fastmap_accurate)
4306 re_compile_fastmap (bufp);
4308 /* See whether the pattern is anchored. */
4309 anchored_start = (bufp->buffer[0] == begline);
4311 #ifdef emacs
4312 gl_state.object = re_match_object; /* Used by SYNTAX_TABLE_BYTE_TO_CHAR. */
4314 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (POS_AS_IN_BUFFER (startpos));
4316 SETUP_SYNTAX_TABLE_FOR_OBJECT (re_match_object, charpos, 1);
4318 #endif
4320 /* Loop through the string, looking for a place to start matching. */
4321 for (;;)
4323 /* If the pattern is anchored,
4324 skip quickly past places we cannot match.
4325 We don't bother to treat startpos == 0 specially
4326 because that case doesn't repeat. */
4327 if (anchored_start && startpos > 0)
4329 if (! ((startpos <= size1 ? string1[startpos - 1]
4330 : string2[startpos - size1 - 1])
4331 == '\n'))
4332 goto advance;
4335 /* If a fastmap is supplied, skip quickly over characters that
4336 cannot be the start of a match. If the pattern can match the
4337 null string, however, we don't need to skip characters; we want
4338 the first null string. */
4339 if (fastmap && startpos < total_size && !bufp->can_be_null)
4341 register re_char *d;
4342 register re_wchar_t buf_ch;
4344 d = POS_ADDR_VSTRING (startpos);
4346 if (range > 0) /* Searching forwards. */
4348 register int lim = 0;
4349 ssize_t irange = range;
4351 if (startpos < size1 && startpos + range >= size1)
4352 lim = range - (size1 - startpos);
4354 /* Written out as an if-else to avoid testing `translate'
4355 inside the loop. */
4356 if (RE_TRANSLATE_P (translate))
4358 if (multibyte)
4359 while (range > lim)
4361 int buf_charlen;
4363 buf_ch = STRING_CHAR_AND_LENGTH (d, buf_charlen);
4364 buf_ch = RE_TRANSLATE (translate, buf_ch);
4365 if (fastmap[CHAR_LEADING_CODE (buf_ch)])
4366 break;
4368 range -= buf_charlen;
4369 d += buf_charlen;
4371 else
4372 while (range > lim)
4374 register re_wchar_t ch, translated;
4376 buf_ch = *d;
4377 ch = RE_CHAR_TO_MULTIBYTE (buf_ch);
4378 translated = RE_TRANSLATE (translate, ch);
4379 if (translated != ch
4380 && (ch = RE_CHAR_TO_UNIBYTE (translated)) >= 0)
4381 buf_ch = ch;
4382 if (fastmap[buf_ch])
4383 break;
4384 d++;
4385 range--;
4388 else
4390 if (multibyte)
4391 while (range > lim)
4393 int buf_charlen;
4395 buf_ch = STRING_CHAR_AND_LENGTH (d, buf_charlen);
4396 if (fastmap[CHAR_LEADING_CODE (buf_ch)])
4397 break;
4398 range -= buf_charlen;
4399 d += buf_charlen;
4401 else
4402 while (range > lim && !fastmap[*d])
4404 d++;
4405 range--;
4408 startpos += irange - range;
4410 else /* Searching backwards. */
4412 if (multibyte)
4414 buf_ch = STRING_CHAR (d);
4415 buf_ch = TRANSLATE (buf_ch);
4416 if (! fastmap[CHAR_LEADING_CODE (buf_ch)])
4417 goto advance;
4419 else
4421 register re_wchar_t ch, translated;
4423 buf_ch = *d;
4424 ch = RE_CHAR_TO_MULTIBYTE (buf_ch);
4425 translated = TRANSLATE (ch);
4426 if (translated != ch
4427 && (ch = RE_CHAR_TO_UNIBYTE (translated)) >= 0)
4428 buf_ch = ch;
4429 if (! fastmap[TRANSLATE (buf_ch)])
4430 goto advance;
4435 /* If can't match the null string, and that's all we have left, fail. */
4436 if (range >= 0 && startpos == total_size && fastmap
4437 && !bufp->can_be_null)
4438 return -1;
4440 val = re_match_2_internal (bufp, string1, size1, string2, size2,
4441 startpos, regs, stop);
4443 if (val >= 0)
4444 return startpos;
4446 if (val == -2)
4447 return -2;
4449 advance:
4450 if (!range)
4451 break;
4452 else if (range > 0)
4454 /* Update STARTPOS to the next character boundary. */
4455 if (multibyte)
4457 re_char *p = POS_ADDR_VSTRING (startpos);
4458 int len = BYTES_BY_CHAR_HEAD (*p);
4460 range -= len;
4461 if (range < 0)
4462 break;
4463 startpos += len;
4465 else
4467 range--;
4468 startpos++;
4471 else
4473 range++;
4474 startpos--;
4476 /* Update STARTPOS to the previous character boundary. */
4477 if (multibyte)
4479 re_char *p = POS_ADDR_VSTRING (startpos) + 1;
4480 re_char *p0 = p;
4481 re_char *phead = HEAD_ADDR_VSTRING (startpos);
4483 /* Find the head of multibyte form. */
4484 PREV_CHAR_BOUNDARY (p, phead);
4485 range += p0 - 1 - p;
4486 if (range > 0)
4487 break;
4489 startpos -= p0 - 1 - p;
4493 return -1;
4494 } /* re_search_2 */
4495 WEAK_ALIAS (__re_search_2, re_search_2)
4497 /* Declarations and macros for re_match_2. */
4499 static int bcmp_translate (re_char *s1, re_char *s2,
4500 register ssize_t len,
4501 RE_TRANSLATE_TYPE translate,
4502 const int multibyte);
4504 /* This converts PTR, a pointer into one of the search strings `string1'
4505 and `string2' into an offset from the beginning of that string. */
4506 #define POINTER_TO_OFFSET(ptr) \
4507 (FIRST_STRING_P (ptr) \
4508 ? (ptr) - string1 \
4509 : (ptr) - string2 + (ptrdiff_t) size1)
4511 /* Call before fetching a character with *d. This switches over to
4512 string2 if necessary.
4513 Check re_match_2_internal for a discussion of why end_match_2 might
4514 not be within string2 (but be equal to end_match_1 instead). */
4515 #define PREFETCH() \
4516 while (d == dend) \
4518 /* End of string2 => fail. */ \
4519 if (dend == end_match_2) \
4520 goto fail; \
4521 /* End of string1 => advance to string2. */ \
4522 d = string2; \
4523 dend = end_match_2; \
4526 /* Call before fetching a char with *d if you already checked other limits.
4527 This is meant for use in lookahead operations like wordend, etc..
4528 where we might need to look at parts of the string that might be
4529 outside of the LIMITs (i.e past `stop'). */
4530 #define PREFETCH_NOLIMIT() \
4531 if (d == end1) \
4533 d = string2; \
4534 dend = end_match_2; \
4537 /* Test if at very beginning or at very end of the virtual concatenation
4538 of `string1' and `string2'. If only one string, it's `string2'. */
4539 #define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
4540 #define AT_STRINGS_END(d) ((d) == end2)
4542 /* Disabled due to a compiler bug -- see comment at case wordbound */
4544 /* The comment at case wordbound is following one, but we don't use
4545 AT_WORD_BOUNDARY anymore to support multibyte form.
4547 The DEC Alpha C compiler 3.x generates incorrect code for the
4548 test WORDCHAR_P (d - 1) != WORDCHAR_P (d) in the expansion of
4549 AT_WORD_BOUNDARY, so this code is disabled. Expanding the
4550 macro and introducing temporary variables works around the bug. */
4552 #if 0
4553 /* Test if D points to a character which is word-constituent. We have
4554 two special cases to check for: if past the end of string1, look at
4555 the first character in string2; and if before the beginning of
4556 string2, look at the last character in string1. */
4557 #define WORDCHAR_P(d) \
4558 (SYNTAX ((d) == end1 ? *string2 \
4559 : (d) == string2 - 1 ? *(end1 - 1) : *(d)) \
4560 == Sword)
4562 /* Test if the character before D and the one at D differ with respect
4563 to being word-constituent. */
4564 #define AT_WORD_BOUNDARY(d) \
4565 (AT_STRINGS_BEG (d) || AT_STRINGS_END (d) \
4566 || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
4567 #endif
4569 /* Free everything we malloc. */
4570 #ifdef MATCH_MAY_ALLOCATE
4571 # define FREE_VAR(var) \
4572 do { \
4573 if (var) \
4575 REGEX_FREE (var); \
4576 var = NULL; \
4578 } while (0)
4579 # define FREE_VARIABLES() \
4580 do { \
4581 REGEX_FREE_STACK (fail_stack.stack); \
4582 FREE_VAR (regstart); \
4583 FREE_VAR (regend); \
4584 FREE_VAR (best_regstart); \
4585 FREE_VAR (best_regend); \
4586 } while (0)
4587 #else
4588 # define FREE_VARIABLES() ((void)0) /* Do nothing! But inhibit gcc warning. */
4589 #endif /* not MATCH_MAY_ALLOCATE */
4592 /* Optimization routines. */
4594 /* If the operation is a match against one or more chars,
4595 return a pointer to the next operation, else return NULL. */
4596 static re_char *
4597 skip_one_char (const re_char *p)
4599 switch (*p++)
4601 case anychar:
4602 break;
4604 case exactn:
4605 p += *p + 1;
4606 break;
4608 case charset_not:
4609 case charset:
4610 if (CHARSET_RANGE_TABLE_EXISTS_P (p - 1))
4612 int mcnt;
4613 p = CHARSET_RANGE_TABLE (p - 1);
4614 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4615 p = CHARSET_RANGE_TABLE_END (p, mcnt);
4617 else
4618 p += 1 + CHARSET_BITMAP_SIZE (p - 1);
4619 break;
4621 case syntaxspec:
4622 case notsyntaxspec:
4623 #ifdef emacs
4624 case categoryspec:
4625 case notcategoryspec:
4626 #endif /* emacs */
4627 p++;
4628 break;
4630 default:
4631 p = NULL;
4633 return p;
4637 /* Jump over non-matching operations. */
4638 static re_char *
4639 skip_noops (const re_char *p, const re_char *pend)
4641 int mcnt;
4642 while (p < pend)
4644 switch (*p)
4646 case start_memory:
4647 case stop_memory:
4648 p += 2; break;
4649 case no_op:
4650 p += 1; break;
4651 case jump:
4652 p += 1;
4653 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4654 p += mcnt;
4655 break;
4656 default:
4657 return p;
4660 assert (p == pend);
4661 return p;
4664 /* Non-zero if "p1 matches something" implies "p2 fails". */
4665 static int
4666 mutually_exclusive_p (struct re_pattern_buffer *bufp, const re_char *p1, const re_char *p2)
4668 re_opcode_t op2;
4669 const boolean multibyte = RE_MULTIBYTE_P (bufp);
4670 unsigned char *pend = bufp->buffer + bufp->used;
4672 assert (p1 >= bufp->buffer && p1 < pend
4673 && p2 >= bufp->buffer && p2 <= pend);
4675 /* Skip over open/close-group commands.
4676 If what follows this loop is a ...+ construct,
4677 look at what begins its body, since we will have to
4678 match at least one of that. */
4679 p2 = skip_noops (p2, pend);
4680 /* The same skip can be done for p1, except that this function
4681 is only used in the case where p1 is a simple match operator. */
4682 /* p1 = skip_noops (p1, pend); */
4684 assert (p1 >= bufp->buffer && p1 < pend
4685 && p2 >= bufp->buffer && p2 <= pend);
4687 op2 = p2 == pend ? succeed : *p2;
4689 switch (op2)
4691 case succeed:
4692 case endbuf:
4693 /* If we're at the end of the pattern, we can change. */
4694 if (skip_one_char (p1))
4696 DEBUG_PRINT (" End of pattern: fast loop.\n");
4697 return 1;
4699 break;
4701 case endline:
4702 case exactn:
4704 register re_wchar_t c
4705 = (re_opcode_t) *p2 == endline ? '\n'
4706 : RE_STRING_CHAR (p2 + 2, multibyte);
4708 if ((re_opcode_t) *p1 == exactn)
4710 if (c != RE_STRING_CHAR (p1 + 2, multibyte))
4712 DEBUG_PRINT (" '%c' != '%c' => fast loop.\n", c, p1[2]);
4713 return 1;
4717 else if ((re_opcode_t) *p1 == charset
4718 || (re_opcode_t) *p1 == charset_not)
4720 int not = (re_opcode_t) *p1 == charset_not;
4722 /* Test if C is listed in charset (or charset_not)
4723 at `p1'. */
4724 if (! multibyte || IS_REAL_ASCII (c))
4726 if (c < CHARSET_BITMAP_SIZE (p1) * BYTEWIDTH
4727 && p1[2 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4728 not = !not;
4730 else if (CHARSET_RANGE_TABLE_EXISTS_P (p1))
4731 CHARSET_LOOKUP_RANGE_TABLE (not, c, p1);
4733 /* `not' is equal to 1 if c would match, which means
4734 that we can't change to pop_failure_jump. */
4735 if (!not)
4737 DEBUG_PRINT (" No match => fast loop.\n");
4738 return 1;
4741 else if ((re_opcode_t) *p1 == anychar
4742 && c == '\n')
4744 DEBUG_PRINT (" . != \\n => fast loop.\n");
4745 return 1;
4748 break;
4750 case charset:
4752 if ((re_opcode_t) *p1 == exactn)
4753 /* Reuse the code above. */
4754 return mutually_exclusive_p (bufp, p2, p1);
4756 /* It is hard to list up all the character in charset
4757 P2 if it includes multibyte character. Give up in
4758 such case. */
4759 else if (!multibyte || !CHARSET_RANGE_TABLE_EXISTS_P (p2))
4761 /* Now, we are sure that P2 has no range table.
4762 So, for the size of bitmap in P2, `p2[1]' is
4763 enough. But P1 may have range table, so the
4764 size of bitmap table of P1 is extracted by
4765 using macro `CHARSET_BITMAP_SIZE'.
4767 In a multibyte case, we know that all the character
4768 listed in P2 is ASCII. In a unibyte case, P1 has only a
4769 bitmap table. So, in both cases, it is enough to test
4770 only the bitmap table of P1. */
4772 if ((re_opcode_t) *p1 == charset)
4774 int idx;
4775 /* We win if the charset inside the loop
4776 has no overlap with the one after the loop. */
4777 for (idx = 0;
4778 (idx < (int) p2[1]
4779 && idx < CHARSET_BITMAP_SIZE (p1));
4780 idx++)
4781 if ((p2[2 + idx] & p1[2 + idx]) != 0)
4782 break;
4784 if (idx == p2[1]
4785 || idx == CHARSET_BITMAP_SIZE (p1))
4787 DEBUG_PRINT (" No match => fast loop.\n");
4788 return 1;
4791 else if ((re_opcode_t) *p1 == charset_not)
4793 int idx;
4794 /* We win if the charset_not inside the loop lists
4795 every character listed in the charset after. */
4796 for (idx = 0; idx < (int) p2[1]; idx++)
4797 if (! (p2[2 + idx] == 0
4798 || (idx < CHARSET_BITMAP_SIZE (p1)
4799 && ((p2[2 + idx] & ~ p1[2 + idx]) == 0))))
4800 break;
4802 if (idx == p2[1])
4804 DEBUG_PRINT (" No match => fast loop.\n");
4805 return 1;
4810 break;
4812 case charset_not:
4813 switch (*p1)
4815 case exactn:
4816 case charset:
4817 /* Reuse the code above. */
4818 return mutually_exclusive_p (bufp, p2, p1);
4819 case charset_not:
4820 /* When we have two charset_not, it's very unlikely that
4821 they don't overlap. The union of the two sets of excluded
4822 chars should cover all possible chars, which, as a matter of
4823 fact, is virtually impossible in multibyte buffers. */
4824 break;
4826 break;
4828 case wordend:
4829 return ((re_opcode_t) *p1 == syntaxspec && p1[1] == Sword);
4830 case symend:
4831 return ((re_opcode_t) *p1 == syntaxspec
4832 && (p1[1] == Ssymbol || p1[1] == Sword));
4833 case notsyntaxspec:
4834 return ((re_opcode_t) *p1 == syntaxspec && p1[1] == p2[1]);
4836 case wordbeg:
4837 return ((re_opcode_t) *p1 == notsyntaxspec && p1[1] == Sword);
4838 case symbeg:
4839 return ((re_opcode_t) *p1 == notsyntaxspec
4840 && (p1[1] == Ssymbol || p1[1] == Sword));
4841 case syntaxspec:
4842 return ((re_opcode_t) *p1 == notsyntaxspec && p1[1] == p2[1]);
4844 case wordbound:
4845 return (((re_opcode_t) *p1 == notsyntaxspec
4846 || (re_opcode_t) *p1 == syntaxspec)
4847 && p1[1] == Sword);
4849 #ifdef emacs
4850 case categoryspec:
4851 return ((re_opcode_t) *p1 == notcategoryspec && p1[1] == p2[1]);
4852 case notcategoryspec:
4853 return ((re_opcode_t) *p1 == categoryspec && p1[1] == p2[1]);
4854 #endif /* emacs */
4856 default:
4860 /* Safe default. */
4861 return 0;
4865 /* Matching routines. */
4867 #ifndef emacs /* Emacs never uses this. */
4868 /* re_match is like re_match_2 except it takes only a single string. */
4870 regoff_t
4871 re_match (struct re_pattern_buffer *bufp, const char *string,
4872 size_t size, ssize_t pos, struct re_registers *regs)
4874 regoff_t result = re_match_2_internal (bufp, NULL, 0, (re_char*) string,
4875 size, pos, regs, size);
4876 return result;
4878 WEAK_ALIAS (__re_match, re_match)
4879 #endif /* not emacs */
4881 #ifdef emacs
4882 /* In Emacs, this is the string or buffer in which we
4883 are matching. It is used for looking up syntax properties. */
4884 Lisp_Object re_match_object;
4885 #endif
4887 /* re_match_2 matches the compiled pattern in BUFP against the
4888 the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
4889 and SIZE2, respectively). We start matching at POS, and stop
4890 matching at STOP.
4892 If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
4893 store offsets for the substring each group matched in REGS. See the
4894 documentation for exactly how many groups we fill.
4896 We return -1 if no match, -2 if an internal error (such as the
4897 failure stack overflowing). Otherwise, we return the length of the
4898 matched substring. */
4900 regoff_t
4901 re_match_2 (struct re_pattern_buffer *bufp, const char *string1,
4902 size_t size1, const char *string2, size_t size2, ssize_t pos,
4903 struct re_registers *regs, ssize_t stop)
4905 regoff_t result;
4907 #ifdef emacs
4908 ssize_t charpos;
4909 gl_state.object = re_match_object; /* Used by SYNTAX_TABLE_BYTE_TO_CHAR. */
4910 charpos = SYNTAX_TABLE_BYTE_TO_CHAR (POS_AS_IN_BUFFER (pos));
4911 SETUP_SYNTAX_TABLE_FOR_OBJECT (re_match_object, charpos, 1);
4912 #endif
4914 result = re_match_2_internal (bufp, (re_char*) string1, size1,
4915 (re_char*) string2, size2,
4916 pos, regs, stop);
4917 return result;
4919 WEAK_ALIAS (__re_match_2, re_match_2)
4922 /* This is a separate function so that we can force an alloca cleanup
4923 afterwards. */
4924 static regoff_t
4925 re_match_2_internal (struct re_pattern_buffer *bufp, const re_char *string1,
4926 size_t size1, const re_char *string2, size_t size2,
4927 ssize_t pos, struct re_registers *regs, ssize_t stop)
4929 /* General temporaries. */
4930 int mcnt;
4931 size_t reg;
4933 /* Just past the end of the corresponding string. */
4934 re_char *end1, *end2;
4936 /* Pointers into string1 and string2, just past the last characters in
4937 each to consider matching. */
4938 re_char *end_match_1, *end_match_2;
4940 /* Where we are in the data, and the end of the current string. */
4941 re_char *d, *dend;
4943 /* Used sometimes to remember where we were before starting matching
4944 an operator so that we can go back in case of failure. This "atomic"
4945 behavior of matching opcodes is indispensable to the correctness
4946 of the on_failure_keep_string_jump optimization. */
4947 re_char *dfail;
4949 /* Where we are in the pattern, and the end of the pattern. */
4950 re_char *p = bufp->buffer;
4951 re_char *pend = p + bufp->used;
4953 /* We use this to map every character in the string. */
4954 RE_TRANSLATE_TYPE translate = bufp->translate;
4956 /* Nonzero if BUFP is setup from a multibyte regex. */
4957 const boolean multibyte = RE_MULTIBYTE_P (bufp);
4959 /* Nonzero if STRING1/STRING2 are multibyte. */
4960 const boolean target_multibyte = RE_TARGET_MULTIBYTE_P (bufp);
4962 /* Failure point stack. Each place that can handle a failure further
4963 down the line pushes a failure point on this stack. It consists of
4964 regstart, and regend for all registers corresponding to
4965 the subexpressions we're currently inside, plus the number of such
4966 registers, and, finally, two char *'s. The first char * is where
4967 to resume scanning the pattern; the second one is where to resume
4968 scanning the strings. */
4969 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
4970 fail_stack_type fail_stack;
4971 #endif
4972 #ifdef DEBUG_COMPILES_ARGUMENTS
4973 unsigned nfailure_points_pushed = 0, nfailure_points_popped = 0;
4974 #endif
4976 #if defined REL_ALLOC && defined REGEX_MALLOC
4977 /* This holds the pointer to the failure stack, when
4978 it is allocated relocatably. */
4979 fail_stack_elt_t *failure_stack_ptr;
4980 #endif
4982 /* We fill all the registers internally, independent of what we
4983 return, for use in backreferences. The number here includes
4984 an element for register zero. */
4985 size_t num_regs = bufp->re_nsub + 1;
4987 /* Information on the contents of registers. These are pointers into
4988 the input strings; they record just what was matched (on this
4989 attempt) by a subexpression part of the pattern, that is, the
4990 regnum-th regstart pointer points to where in the pattern we began
4991 matching and the regnum-th regend points to right after where we
4992 stopped matching the regnum-th subexpression. (The zeroth register
4993 keeps track of what the whole pattern matches.) */
4994 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
4995 re_char **regstart, **regend;
4996 #endif
4998 /* The following record the register info as found in the above
4999 variables when we find a match better than any we've seen before.
5000 This happens as we backtrack through the failure points, which in
5001 turn happens only if we have not yet matched the entire string. */
5002 unsigned best_regs_set = false;
5003 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
5004 re_char **best_regstart, **best_regend;
5005 #endif
5007 /* Logically, this is `best_regend[0]'. But we don't want to have to
5008 allocate space for that if we're not allocating space for anything
5009 else (see below). Also, we never need info about register 0 for
5010 any of the other register vectors, and it seems rather a kludge to
5011 treat `best_regend' differently than the rest. So we keep track of
5012 the end of the best match so far in a separate variable. We
5013 initialize this to NULL so that when we backtrack the first time
5014 and need to test it, it's not garbage. */
5015 re_char *match_end = NULL;
5017 #ifdef DEBUG_COMPILES_ARGUMENTS
5018 /* Counts the total number of registers pushed. */
5019 unsigned num_regs_pushed = 0;
5020 #endif
5022 DEBUG_PRINT ("\n\nEntering re_match_2.\n");
5024 INIT_FAIL_STACK ();
5026 #ifdef MATCH_MAY_ALLOCATE
5027 /* Do not bother to initialize all the register variables if there are
5028 no groups in the pattern, as it takes a fair amount of time. If
5029 there are groups, we include space for register 0 (the whole
5030 pattern), even though we never use it, since it simplifies the
5031 array indexing. We should fix this. */
5032 if (bufp->re_nsub)
5034 regstart = REGEX_TALLOC (num_regs, re_char *);
5035 regend = REGEX_TALLOC (num_regs, re_char *);
5036 best_regstart = REGEX_TALLOC (num_regs, re_char *);
5037 best_regend = REGEX_TALLOC (num_regs, re_char *);
5039 if (!(regstart && regend && best_regstart && best_regend))
5041 FREE_VARIABLES ();
5042 return -2;
5045 else
5047 /* We must initialize all our variables to NULL, so that
5048 `FREE_VARIABLES' doesn't try to free them. */
5049 regstart = regend = best_regstart = best_regend = NULL;
5051 #endif /* MATCH_MAY_ALLOCATE */
5053 /* The starting position is bogus. */
5054 if (pos < 0 || pos > size1 + size2)
5056 FREE_VARIABLES ();
5057 return -1;
5060 /* Initialize subexpression text positions to -1 to mark ones that no
5061 start_memory/stop_memory has been seen for. Also initialize the
5062 register information struct. */
5063 for (reg = 1; reg < num_regs; reg++)
5064 regstart[reg] = regend[reg] = NULL;
5066 /* We move `string1' into `string2' if the latter's empty -- but not if
5067 `string1' is null. */
5068 if (size2 == 0 && string1 != NULL)
5070 string2 = string1;
5071 size2 = size1;
5072 string1 = 0;
5073 size1 = 0;
5075 end1 = string1 + size1;
5076 end2 = string2 + size2;
5078 /* `p' scans through the pattern as `d' scans through the data.
5079 `dend' is the end of the input string that `d' points within. `d'
5080 is advanced into the following input string whenever necessary, but
5081 this happens before fetching; therefore, at the beginning of the
5082 loop, `d' can be pointing at the end of a string, but it cannot
5083 equal `string2'. */
5084 if (pos >= size1)
5086 /* Only match within string2. */
5087 d = string2 + pos - size1;
5088 dend = end_match_2 = string2 + stop - size1;
5089 end_match_1 = end1; /* Just to give it a value. */
5091 else
5093 if (stop < size1)
5095 /* Only match within string1. */
5096 end_match_1 = string1 + stop;
5097 /* BEWARE!
5098 When we reach end_match_1, PREFETCH normally switches to string2.
5099 But in the present case, this means that just doing a PREFETCH
5100 makes us jump from `stop' to `gap' within the string.
5101 What we really want here is for the search to stop as
5102 soon as we hit end_match_1. That's why we set end_match_2
5103 to end_match_1 (since PREFETCH fails as soon as we hit
5104 end_match_2). */
5105 end_match_2 = end_match_1;
5107 else
5108 { /* It's important to use this code when stop == size so that
5109 moving `d' from end1 to string2 will not prevent the d == dend
5110 check from catching the end of string. */
5111 end_match_1 = end1;
5112 end_match_2 = string2 + stop - size1;
5114 d = string1 + pos;
5115 dend = end_match_1;
5118 DEBUG_PRINT ("The compiled pattern is: ");
5119 DEBUG_PRINT_COMPILED_PATTERN (bufp, p, pend);
5120 DEBUG_PRINT ("The string to match is: `");
5121 DEBUG_PRINT_DOUBLE_STRING (d, string1, size1, string2, size2);
5122 DEBUG_PRINT ("'\n");
5124 /* This loops over pattern commands. It exits by returning from the
5125 function if the match is complete, or it drops through if the match
5126 fails at this starting point in the input data. */
5127 for (;;)
5129 DEBUG_PRINT ("\n%p: ", p);
5131 if (p == pend)
5133 ptrdiff_t dcnt;
5135 /* End of pattern means we might have succeeded. */
5136 DEBUG_PRINT ("end of pattern ... ");
5138 /* If we haven't matched the entire string, and we want the
5139 longest match, try backtracking. */
5140 if (d != end_match_2)
5142 /* 1 if this match ends in the same string (string1 or string2)
5143 as the best previous match. */
5144 boolean same_str_p = (FIRST_STRING_P (match_end)
5145 == FIRST_STRING_P (d));
5146 /* 1 if this match is the best seen so far. */
5147 boolean best_match_p;
5149 /* AIX compiler got confused when this was combined
5150 with the previous declaration. */
5151 if (same_str_p)
5152 best_match_p = d > match_end;
5153 else
5154 best_match_p = !FIRST_STRING_P (d);
5156 DEBUG_PRINT ("backtracking.\n");
5158 if (!FAIL_STACK_EMPTY ())
5159 { /* More failure points to try. */
5161 /* If exceeds best match so far, save it. */
5162 if (!best_regs_set || best_match_p)
5164 best_regs_set = true;
5165 match_end = d;
5167 DEBUG_PRINT ("\nSAVING match as best so far.\n");
5169 for (reg = 1; reg < num_regs; reg++)
5171 best_regstart[reg] = regstart[reg];
5172 best_regend[reg] = regend[reg];
5175 goto fail;
5178 /* If no failure points, don't restore garbage. And if
5179 last match is real best match, don't restore second
5180 best one. */
5181 else if (best_regs_set && !best_match_p)
5183 restore_best_regs:
5184 /* Restore best match. It may happen that `dend ==
5185 end_match_1' while the restored d is in string2.
5186 For example, the pattern `x.*y.*z' against the
5187 strings `x-' and `y-z-', if the two strings are
5188 not consecutive in memory. */
5189 DEBUG_PRINT ("Restoring best registers.\n");
5191 d = match_end;
5192 dend = ((d >= string1 && d <= end1)
5193 ? end_match_1 : end_match_2);
5195 for (reg = 1; reg < num_regs; reg++)
5197 regstart[reg] = best_regstart[reg];
5198 regend[reg] = best_regend[reg];
5201 } /* d != end_match_2 */
5203 succeed_label:
5204 DEBUG_PRINT ("Accepting match.\n");
5206 /* If caller wants register contents data back, do it. */
5207 if (regs && !bufp->no_sub)
5209 /* Have the register data arrays been allocated? */
5210 if (bufp->regs_allocated == REGS_UNALLOCATED)
5211 { /* No. So allocate them with malloc. We need one
5212 extra element beyond `num_regs' for the `-1' marker
5213 GNU code uses. */
5214 regs->num_regs = MAX (RE_NREGS, num_regs + 1);
5215 regs->start = TALLOC (regs->num_regs, regoff_t);
5216 regs->end = TALLOC (regs->num_regs, regoff_t);
5217 if (regs->start == NULL || regs->end == NULL)
5219 FREE_VARIABLES ();
5220 return -2;
5222 bufp->regs_allocated = REGS_REALLOCATE;
5224 else if (bufp->regs_allocated == REGS_REALLOCATE)
5225 { /* Yes. If we need more elements than were already
5226 allocated, reallocate them. If we need fewer, just
5227 leave it alone. */
5228 if (regs->num_regs < num_regs + 1)
5230 regs->num_regs = num_regs + 1;
5231 RETALLOC (regs->start, regs->num_regs, regoff_t);
5232 RETALLOC (regs->end, regs->num_regs, regoff_t);
5233 if (regs->start == NULL || regs->end == NULL)
5235 FREE_VARIABLES ();
5236 return -2;
5240 else
5242 /* These braces fend off a "empty body in an else-statement"
5243 warning under GCC when assert expands to nothing. */
5244 assert (bufp->regs_allocated == REGS_FIXED);
5247 /* Convert the pointer data in `regstart' and `regend' to
5248 indices. Register zero has to be set differently,
5249 since we haven't kept track of any info for it. */
5250 if (regs->num_regs > 0)
5252 regs->start[0] = pos;
5253 regs->end[0] = POINTER_TO_OFFSET (d);
5256 /* Go through the first `min (num_regs, regs->num_regs)'
5257 registers, since that is all we initialized. */
5258 for (reg = 1; reg < MIN (num_regs, regs->num_regs); reg++)
5260 if (REG_UNSET (regstart[reg]) || REG_UNSET (regend[reg]))
5261 regs->start[reg] = regs->end[reg] = -1;
5262 else
5264 regs->start[reg] = POINTER_TO_OFFSET (regstart[reg]);
5265 regs->end[reg] = POINTER_TO_OFFSET (regend[reg]);
5269 /* If the regs structure we return has more elements than
5270 were in the pattern, set the extra elements to -1. If
5271 we (re)allocated the registers, this is the case,
5272 because we always allocate enough to have at least one
5273 -1 at the end. */
5274 for (reg = num_regs; reg < regs->num_regs; reg++)
5275 regs->start[reg] = regs->end[reg] = -1;
5276 } /* regs && !bufp->no_sub */
5278 DEBUG_PRINT ("%u failure points pushed, %u popped (%u remain).\n",
5279 nfailure_points_pushed, nfailure_points_popped,
5280 nfailure_points_pushed - nfailure_points_popped);
5281 DEBUG_PRINT ("%u registers pushed.\n", num_regs_pushed);
5283 dcnt = POINTER_TO_OFFSET (d) - pos;
5285 DEBUG_PRINT ("Returning %td from re_match_2.\n", dcnt);
5287 FREE_VARIABLES ();
5288 return dcnt;
5291 /* Otherwise match next pattern command. */
5292 switch (*p++)
5294 /* Ignore these. Used to ignore the n of succeed_n's which
5295 currently have n == 0. */
5296 case no_op:
5297 DEBUG_PRINT ("EXECUTING no_op.\n");
5298 break;
5300 case succeed:
5301 DEBUG_PRINT ("EXECUTING succeed.\n");
5302 goto succeed_label;
5304 /* Match the next n pattern characters exactly. The following
5305 byte in the pattern defines n, and the n bytes after that
5306 are the characters to match. */
5307 case exactn:
5308 mcnt = *p++;
5309 DEBUG_PRINT ("EXECUTING exactn %d.\n", mcnt);
5311 /* Remember the start point to rollback upon failure. */
5312 dfail = d;
5314 #ifndef emacs
5315 /* This is written out as an if-else so we don't waste time
5316 testing `translate' inside the loop. */
5317 if (RE_TRANSLATE_P (translate))
5320 PREFETCH ();
5321 if (RE_TRANSLATE (translate, *d) != *p++)
5323 d = dfail;
5324 goto fail;
5326 d++;
5328 while (--mcnt);
5329 else
5332 PREFETCH ();
5333 if (*d++ != *p++)
5335 d = dfail;
5336 goto fail;
5339 while (--mcnt);
5340 #else /* emacs */
5341 /* The cost of testing `translate' is comparatively small. */
5342 if (target_multibyte)
5345 int pat_charlen, buf_charlen;
5346 int pat_ch, buf_ch;
5348 PREFETCH ();
5349 if (multibyte)
5350 pat_ch = STRING_CHAR_AND_LENGTH (p, pat_charlen);
5351 else
5353 pat_ch = RE_CHAR_TO_MULTIBYTE (*p);
5354 pat_charlen = 1;
5356 buf_ch = STRING_CHAR_AND_LENGTH (d, buf_charlen);
5358 if (TRANSLATE (buf_ch) != pat_ch)
5360 d = dfail;
5361 goto fail;
5364 p += pat_charlen;
5365 d += buf_charlen;
5366 mcnt -= pat_charlen;
5368 while (mcnt > 0);
5369 else
5372 int pat_charlen;
5373 int pat_ch, buf_ch;
5375 PREFETCH ();
5376 if (multibyte)
5378 pat_ch = STRING_CHAR_AND_LENGTH (p, pat_charlen);
5379 pat_ch = RE_CHAR_TO_UNIBYTE (pat_ch);
5381 else
5383 pat_ch = *p;
5384 pat_charlen = 1;
5386 buf_ch = RE_CHAR_TO_MULTIBYTE (*d);
5387 if (! CHAR_BYTE8_P (buf_ch))
5389 buf_ch = TRANSLATE (buf_ch);
5390 buf_ch = RE_CHAR_TO_UNIBYTE (buf_ch);
5391 if (buf_ch < 0)
5392 buf_ch = *d;
5394 else
5395 buf_ch = *d;
5396 if (buf_ch != pat_ch)
5398 d = dfail;
5399 goto fail;
5401 p += pat_charlen;
5402 d++;
5404 while (--mcnt);
5405 #endif
5406 break;
5409 /* Match any character except possibly a newline or a null. */
5410 case anychar:
5412 int buf_charlen;
5413 re_wchar_t buf_ch;
5415 DEBUG_PRINT ("EXECUTING anychar.\n");
5417 PREFETCH ();
5418 buf_ch = RE_STRING_CHAR_AND_LENGTH (d, buf_charlen,
5419 target_multibyte);
5420 buf_ch = TRANSLATE (buf_ch);
5422 if ((!(bufp->syntax & RE_DOT_NEWLINE)
5423 && buf_ch == '\n')
5424 || ((bufp->syntax & RE_DOT_NOT_NULL)
5425 && buf_ch == '\000'))
5426 goto fail;
5428 DEBUG_PRINT (" Matched `%d'.\n", *d);
5429 d += buf_charlen;
5431 break;
5434 case charset:
5435 case charset_not:
5437 register unsigned int c;
5438 boolean not = (re_opcode_t) *(p - 1) == charset_not;
5439 int len;
5441 /* Start of actual range_table, or end of bitmap if there is no
5442 range table. */
5443 re_char *range_table IF_LINT (= NULL);
5445 /* Nonzero if there is a range table. */
5446 int range_table_exists;
5448 /* Number of ranges of range table. This is not included
5449 in the initial byte-length of the command. */
5450 int count = 0;
5452 /* Whether matching against a unibyte character. */
5453 boolean unibyte_char = false;
5455 DEBUG_PRINT ("EXECUTING charset%s.\n", not ? "_not" : "");
5457 range_table_exists = CHARSET_RANGE_TABLE_EXISTS_P (&p[-1]);
5459 if (range_table_exists)
5461 range_table = CHARSET_RANGE_TABLE (&p[-1]); /* Past the bitmap. */
5462 EXTRACT_NUMBER_AND_INCR (count, range_table);
5465 PREFETCH ();
5466 c = RE_STRING_CHAR_AND_LENGTH (d, len, target_multibyte);
5467 if (target_multibyte)
5469 int c1;
5471 c = TRANSLATE (c);
5472 c1 = RE_CHAR_TO_UNIBYTE (c);
5473 if (c1 >= 0)
5475 unibyte_char = true;
5476 c = c1;
5479 else
5481 int c1 = RE_CHAR_TO_MULTIBYTE (c);
5483 if (! CHAR_BYTE8_P (c1))
5485 c1 = TRANSLATE (c1);
5486 c1 = RE_CHAR_TO_UNIBYTE (c1);
5487 if (c1 >= 0)
5489 unibyte_char = true;
5490 c = c1;
5493 else
5494 unibyte_char = true;
5497 if (unibyte_char && c < (1 << BYTEWIDTH))
5498 { /* Lookup bitmap. */
5499 /* Cast to `unsigned' instead of `unsigned char' in
5500 case the bit list is a full 32 bytes long. */
5501 if (c < (unsigned) (CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH)
5502 && p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
5503 not = !not;
5505 #ifdef emacs
5506 else if (range_table_exists)
5508 int class_bits = CHARSET_RANGE_TABLE_BITS (&p[-1]);
5510 if ( (class_bits & BIT_LOWER && ISLOWER (c))
5511 | (class_bits & BIT_MULTIBYTE)
5512 | (class_bits & BIT_PUNCT && ISPUNCT (c))
5513 | (class_bits & BIT_SPACE && ISSPACE (c))
5514 | (class_bits & BIT_UPPER && ISUPPER (c))
5515 | (class_bits & BIT_WORD && ISWORD (c)))
5516 not = !not;
5517 else
5518 CHARSET_LOOKUP_RANGE_TABLE_RAW (not, c, range_table, count);
5520 #endif /* emacs */
5522 if (range_table_exists)
5523 p = CHARSET_RANGE_TABLE_END (range_table, count);
5524 else
5525 p += CHARSET_BITMAP_SIZE (&p[-1]) + 1;
5527 if (!not) goto fail;
5529 d += len;
5531 break;
5534 /* The beginning of a group is represented by start_memory.
5535 The argument is the register number. The text
5536 matched within the group is recorded (in the internal
5537 registers data structure) under the register number. */
5538 case start_memory:
5539 DEBUG_PRINT ("EXECUTING start_memory %d:\n", *p);
5541 /* In case we need to undo this operation (via backtracking). */
5542 PUSH_FAILURE_REG (*p);
5544 regstart[*p] = d;
5545 regend[*p] = NULL; /* probably unnecessary. -sm */
5546 DEBUG_PRINT (" regstart: %td\n", POINTER_TO_OFFSET (regstart[*p]));
5548 /* Move past the register number and inner group count. */
5549 p += 1;
5550 break;
5553 /* The stop_memory opcode represents the end of a group. Its
5554 argument is the same as start_memory's: the register number. */
5555 case stop_memory:
5556 DEBUG_PRINT ("EXECUTING stop_memory %d:\n", *p);
5558 assert (!REG_UNSET (regstart[*p]));
5559 /* Strictly speaking, there should be code such as:
5561 assert (REG_UNSET (regend[*p]));
5562 PUSH_FAILURE_REGSTOP ((unsigned int)*p);
5564 But the only info to be pushed is regend[*p] and it is known to
5565 be UNSET, so there really isn't anything to push.
5566 Not pushing anything, on the other hand deprives us from the
5567 guarantee that regend[*p] is UNSET since undoing this operation
5568 will not reset its value properly. This is not important since
5569 the value will only be read on the next start_memory or at
5570 the very end and both events can only happen if this stop_memory
5571 is *not* undone. */
5573 regend[*p] = d;
5574 DEBUG_PRINT (" regend: %td\n", POINTER_TO_OFFSET (regend[*p]));
5576 /* Move past the register number and the inner group count. */
5577 p += 1;
5578 break;
5581 /* \<digit> has been turned into a `duplicate' command which is
5582 followed by the numeric value of <digit> as the register number. */
5583 case duplicate:
5585 register re_char *d2, *dend2;
5586 int regno = *p++; /* Get which register to match against. */
5587 DEBUG_PRINT ("EXECUTING duplicate %d.\n", regno);
5589 /* Can't back reference a group which we've never matched. */
5590 if (REG_UNSET (regstart[regno]) || REG_UNSET (regend[regno]))
5591 goto fail;
5593 /* Where in input to try to start matching. */
5594 d2 = regstart[regno];
5596 /* Remember the start point to rollback upon failure. */
5597 dfail = d;
5599 /* Where to stop matching; if both the place to start and
5600 the place to stop matching are in the same string, then
5601 set to the place to stop, otherwise, for now have to use
5602 the end of the first string. */
5604 dend2 = ((FIRST_STRING_P (regstart[regno])
5605 == FIRST_STRING_P (regend[regno]))
5606 ? regend[regno] : end_match_1);
5607 for (;;)
5609 ptrdiff_t dcnt;
5611 /* If necessary, advance to next segment in register
5612 contents. */
5613 while (d2 == dend2)
5615 if (dend2 == end_match_2) break;
5616 if (dend2 == regend[regno]) break;
5618 /* End of string1 => advance to string2. */
5619 d2 = string2;
5620 dend2 = regend[regno];
5622 /* At end of register contents => success */
5623 if (d2 == dend2) break;
5625 /* If necessary, advance to next segment in data. */
5626 PREFETCH ();
5628 /* How many characters left in this segment to match. */
5629 dcnt = dend - d;
5631 /* Want how many consecutive characters we can match in
5632 one shot, so, if necessary, adjust the count. */
5633 if (dcnt > dend2 - d2)
5634 dcnt = dend2 - d2;
5636 /* Compare that many; failure if mismatch, else move
5637 past them. */
5638 if (RE_TRANSLATE_P (translate)
5639 ? bcmp_translate (d, d2, dcnt, translate, target_multibyte)
5640 : memcmp (d, d2, dcnt))
5642 d = dfail;
5643 goto fail;
5645 d += dcnt, d2 += dcnt;
5648 break;
5651 /* begline matches the empty string at the beginning of the string
5652 (unless `not_bol' is set in `bufp'), and after newlines. */
5653 case begline:
5654 DEBUG_PRINT ("EXECUTING begline.\n");
5656 if (AT_STRINGS_BEG (d))
5658 if (!bufp->not_bol) break;
5660 else
5662 unsigned c;
5663 GET_CHAR_BEFORE_2 (c, d, string1, end1, string2, end2);
5664 if (c == '\n')
5665 break;
5667 /* In all other cases, we fail. */
5668 goto fail;
5671 /* endline is the dual of begline. */
5672 case endline:
5673 DEBUG_PRINT ("EXECUTING endline.\n");
5675 if (AT_STRINGS_END (d))
5677 if (!bufp->not_eol) break;
5679 else
5681 PREFETCH_NOLIMIT ();
5682 if (*d == '\n')
5683 break;
5685 goto fail;
5688 /* Match at the very beginning of the data. */
5689 case begbuf:
5690 DEBUG_PRINT ("EXECUTING begbuf.\n");
5691 if (AT_STRINGS_BEG (d))
5692 break;
5693 goto fail;
5696 /* Match at the very end of the data. */
5697 case endbuf:
5698 DEBUG_PRINT ("EXECUTING endbuf.\n");
5699 if (AT_STRINGS_END (d))
5700 break;
5701 goto fail;
5704 /* on_failure_keep_string_jump is used to optimize `.*\n'. It
5705 pushes NULL as the value for the string on the stack. Then
5706 `POP_FAILURE_POINT' will keep the current value for the
5707 string, instead of restoring it. To see why, consider
5708 matching `foo\nbar' against `.*\n'. The .* matches the foo;
5709 then the . fails against the \n. But the next thing we want
5710 to do is match the \n against the \n; if we restored the
5711 string value, we would be back at the foo.
5713 Because this is used only in specific cases, we don't need to
5714 check all the things that `on_failure_jump' does, to make
5715 sure the right things get saved on the stack. Hence we don't
5716 share its code. The only reason to push anything on the
5717 stack at all is that otherwise we would have to change
5718 `anychar's code to do something besides goto fail in this
5719 case; that seems worse than this. */
5720 case on_failure_keep_string_jump:
5721 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5722 DEBUG_PRINT ("EXECUTING on_failure_keep_string_jump %d (to %p):\n",
5723 mcnt, p + mcnt);
5725 PUSH_FAILURE_POINT (p - 3, NULL);
5726 break;
5728 /* A nasty loop is introduced by the non-greedy *? and +?.
5729 With such loops, the stack only ever contains one failure point
5730 at a time, so that a plain on_failure_jump_loop kind of
5731 cycle detection cannot work. Worse yet, such a detection
5732 can not only fail to detect a cycle, but it can also wrongly
5733 detect a cycle (between different instantiations of the same
5734 loop).
5735 So the method used for those nasty loops is a little different:
5736 We use a special cycle-detection-stack-frame which is pushed
5737 when the on_failure_jump_nastyloop failure-point is *popped*.
5738 This special frame thus marks the beginning of one iteration
5739 through the loop and we can hence easily check right here
5740 whether something matched between the beginning and the end of
5741 the loop. */
5742 case on_failure_jump_nastyloop:
5743 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5744 DEBUG_PRINT ("EXECUTING on_failure_jump_nastyloop %d (to %p):\n",
5745 mcnt, p + mcnt);
5747 assert ((re_opcode_t)p[-4] == no_op);
5749 int cycle = 0;
5750 CHECK_INFINITE_LOOP (p - 4, d);
5751 if (!cycle)
5752 /* If there's a cycle, just continue without pushing
5753 this failure point. The failure point is the "try again"
5754 option, which shouldn't be tried.
5755 We want (x?)*?y\1z to match both xxyz and xxyxz. */
5756 PUSH_FAILURE_POINT (p - 3, d);
5758 break;
5760 /* Simple loop detecting on_failure_jump: just check on the
5761 failure stack if the same spot was already hit earlier. */
5762 case on_failure_jump_loop:
5763 on_failure:
5764 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5765 DEBUG_PRINT ("EXECUTING on_failure_jump_loop %d (to %p):\n",
5766 mcnt, p + mcnt);
5768 int cycle = 0;
5769 CHECK_INFINITE_LOOP (p - 3, d);
5770 if (cycle)
5771 /* If there's a cycle, get out of the loop, as if the matching
5772 had failed. We used to just `goto fail' here, but that was
5773 aborting the search a bit too early: we want to keep the
5774 empty-loop-match and keep matching after the loop.
5775 We want (x?)*y\1z to match both xxyz and xxyxz. */
5776 p += mcnt;
5777 else
5778 PUSH_FAILURE_POINT (p - 3, d);
5780 break;
5783 /* Uses of on_failure_jump:
5785 Each alternative starts with an on_failure_jump that points
5786 to the beginning of the next alternative. Each alternative
5787 except the last ends with a jump that in effect jumps past
5788 the rest of the alternatives. (They really jump to the
5789 ending jump of the following alternative, because tensioning
5790 these jumps is a hassle.)
5792 Repeats start with an on_failure_jump that points past both
5793 the repetition text and either the following jump or
5794 pop_failure_jump back to this on_failure_jump. */
5795 case on_failure_jump:
5796 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5797 DEBUG_PRINT ("EXECUTING on_failure_jump %d (to %p):\n",
5798 mcnt, p + mcnt);
5800 PUSH_FAILURE_POINT (p -3, d);
5801 break;
5803 /* This operation is used for greedy *.
5804 Compare the beginning of the repeat with what in the
5805 pattern follows its end. If we can establish that there
5806 is nothing that they would both match, i.e., that we
5807 would have to backtrack because of (as in, e.g., `a*a')
5808 then we can use a non-backtracking loop based on
5809 on_failure_keep_string_jump instead of on_failure_jump. */
5810 case on_failure_jump_smart:
5811 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5812 DEBUG_PRINT ("EXECUTING on_failure_jump_smart %d (to %p).\n",
5813 mcnt, p + mcnt);
5815 re_char *p1 = p; /* Next operation. */
5816 /* Here, we discard `const', making re_match non-reentrant. */
5817 unsigned char *p2 = (unsigned char*) p + mcnt; /* Jump dest. */
5818 unsigned char *p3 = (unsigned char*) p - 3; /* opcode location. */
5820 p -= 3; /* Reset so that we will re-execute the
5821 instruction once it's been changed. */
5823 EXTRACT_NUMBER (mcnt, p2 - 2);
5825 /* Ensure this is a indeed the trivial kind of loop
5826 we are expecting. */
5827 assert (skip_one_char (p1) == p2 - 3);
5828 assert ((re_opcode_t) p2[-3] == jump && p2 + mcnt == p);
5829 DEBUG_STATEMENT (debug += 2);
5830 if (mutually_exclusive_p (bufp, p1, p2))
5832 /* Use a fast `on_failure_keep_string_jump' loop. */
5833 DEBUG_PRINT (" smart exclusive => fast loop.\n");
5834 *p3 = (unsigned char) on_failure_keep_string_jump;
5835 STORE_NUMBER (p2 - 2, mcnt + 3);
5837 else
5839 /* Default to a safe `on_failure_jump' loop. */
5840 DEBUG_PRINT (" smart default => slow loop.\n");
5841 *p3 = (unsigned char) on_failure_jump;
5843 DEBUG_STATEMENT (debug -= 2);
5845 break;
5847 /* Unconditionally jump (without popping any failure points). */
5848 case jump:
5849 unconditional_jump:
5850 IMMEDIATE_QUIT_CHECK;
5851 EXTRACT_NUMBER_AND_INCR (mcnt, p); /* Get the amount to jump. */
5852 DEBUG_PRINT ("EXECUTING jump %d ", mcnt);
5853 p += mcnt; /* Do the jump. */
5854 DEBUG_PRINT ("(to %p).\n", p);
5855 break;
5858 /* Have to succeed matching what follows at least n times.
5859 After that, handle like `on_failure_jump'. */
5860 case succeed_n:
5861 /* Signedness doesn't matter since we only compare MCNT to 0. */
5862 EXTRACT_NUMBER (mcnt, p + 2);
5863 DEBUG_PRINT ("EXECUTING succeed_n %d.\n", mcnt);
5865 /* Originally, mcnt is how many times we HAVE to succeed. */
5866 if (mcnt != 0)
5868 /* Here, we discard `const', making re_match non-reentrant. */
5869 unsigned char *p2 = (unsigned char*) p + 2; /* counter loc. */
5870 mcnt--;
5871 p += 4;
5872 PUSH_NUMBER (p2, mcnt);
5874 else
5875 /* The two bytes encoding mcnt == 0 are two no_op opcodes. */
5876 goto on_failure;
5877 break;
5879 case jump_n:
5880 /* Signedness doesn't matter since we only compare MCNT to 0. */
5881 EXTRACT_NUMBER (mcnt, p + 2);
5882 DEBUG_PRINT ("EXECUTING jump_n %d.\n", mcnt);
5884 /* Originally, this is how many times we CAN jump. */
5885 if (mcnt != 0)
5887 /* Here, we discard `const', making re_match non-reentrant. */
5888 unsigned char *p2 = (unsigned char*) p + 2; /* counter loc. */
5889 mcnt--;
5890 PUSH_NUMBER (p2, mcnt);
5891 goto unconditional_jump;
5893 /* If don't have to jump any more, skip over the rest of command. */
5894 else
5895 p += 4;
5896 break;
5898 case set_number_at:
5900 unsigned char *p2; /* Location of the counter. */
5901 DEBUG_PRINT ("EXECUTING set_number_at.\n");
5903 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5904 /* Here, we discard `const', making re_match non-reentrant. */
5905 p2 = (unsigned char*) p + mcnt;
5906 /* Signedness doesn't matter since we only copy MCNT's bits . */
5907 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5908 DEBUG_PRINT (" Setting %p to %d.\n", p2, mcnt);
5909 PUSH_NUMBER (p2, mcnt);
5910 break;
5913 case wordbound:
5914 case notwordbound:
5916 boolean not = (re_opcode_t) *(p - 1) == notwordbound;
5917 DEBUG_PRINT ("EXECUTING %swordbound.\n", not ? "not" : "");
5919 /* We SUCCEED (or FAIL) in one of the following cases: */
5921 /* Case 1: D is at the beginning or the end of string. */
5922 if (AT_STRINGS_BEG (d) || AT_STRINGS_END (d))
5923 not = !not;
5924 else
5926 /* C1 is the character before D, S1 is the syntax of C1, C2
5927 is the character at D, and S2 is the syntax of C2. */
5928 re_wchar_t c1, c2;
5929 int s1, s2;
5930 int dummy;
5931 #ifdef emacs
5932 ssize_t offset = PTR_TO_OFFSET (d - 1);
5933 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5934 UPDATE_SYNTAX_TABLE (charpos);
5935 #endif
5936 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5937 s1 = SYNTAX (c1);
5938 #ifdef emacs
5939 UPDATE_SYNTAX_TABLE_FORWARD (charpos + 1);
5940 #endif
5941 PREFETCH_NOLIMIT ();
5942 GET_CHAR_AFTER (c2, d, dummy);
5943 s2 = SYNTAX (c2);
5945 if (/* Case 2: Only one of S1 and S2 is Sword. */
5946 ((s1 == Sword) != (s2 == Sword))
5947 /* Case 3: Both of S1 and S2 are Sword, and macro
5948 WORD_BOUNDARY_P (C1, C2) returns nonzero. */
5949 || ((s1 == Sword) && WORD_BOUNDARY_P (c1, c2)))
5950 not = !not;
5952 if (not)
5953 break;
5954 else
5955 goto fail;
5958 case wordbeg:
5959 DEBUG_PRINT ("EXECUTING wordbeg.\n");
5961 /* We FAIL in one of the following cases: */
5963 /* Case 1: D is at the end of string. */
5964 if (AT_STRINGS_END (d))
5965 goto fail;
5966 else
5968 /* C1 is the character before D, S1 is the syntax of C1, C2
5969 is the character at D, and S2 is the syntax of C2. */
5970 re_wchar_t c1, c2;
5971 int s1, s2;
5972 int dummy;
5973 #ifdef emacs
5974 ssize_t offset = PTR_TO_OFFSET (d);
5975 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5976 UPDATE_SYNTAX_TABLE (charpos);
5977 #endif
5978 PREFETCH ();
5979 GET_CHAR_AFTER (c2, d, dummy);
5980 s2 = SYNTAX (c2);
5982 /* Case 2: S2 is not Sword. */
5983 if (s2 != Sword)
5984 goto fail;
5986 /* Case 3: D is not at the beginning of string ... */
5987 if (!AT_STRINGS_BEG (d))
5989 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5990 #ifdef emacs
5991 UPDATE_SYNTAX_TABLE_BACKWARD (charpos - 1);
5992 #endif
5993 s1 = SYNTAX (c1);
5995 /* ... and S1 is Sword, and WORD_BOUNDARY_P (C1, C2)
5996 returns 0. */
5997 if ((s1 == Sword) && !WORD_BOUNDARY_P (c1, c2))
5998 goto fail;
6001 break;
6003 case wordend:
6004 DEBUG_PRINT ("EXECUTING wordend.\n");
6006 /* We FAIL in one of the following cases: */
6008 /* Case 1: D is at the beginning of string. */
6009 if (AT_STRINGS_BEG (d))
6010 goto fail;
6011 else
6013 /* C1 is the character before D, S1 is the syntax of C1, C2
6014 is the character at D, and S2 is the syntax of C2. */
6015 re_wchar_t c1, c2;
6016 int s1, s2;
6017 int dummy;
6018 #ifdef emacs
6019 ssize_t offset = PTR_TO_OFFSET (d) - 1;
6020 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
6021 UPDATE_SYNTAX_TABLE (charpos);
6022 #endif
6023 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
6024 s1 = SYNTAX (c1);
6026 /* Case 2: S1 is not Sword. */
6027 if (s1 != Sword)
6028 goto fail;
6030 /* Case 3: D is not at the end of string ... */
6031 if (!AT_STRINGS_END (d))
6033 PREFETCH_NOLIMIT ();
6034 GET_CHAR_AFTER (c2, d, dummy);
6035 #ifdef emacs
6036 UPDATE_SYNTAX_TABLE_FORWARD (charpos);
6037 #endif
6038 s2 = SYNTAX (c2);
6040 /* ... and S2 is Sword, and WORD_BOUNDARY_P (C1, C2)
6041 returns 0. */
6042 if ((s2 == Sword) && !WORD_BOUNDARY_P (c1, c2))
6043 goto fail;
6046 break;
6048 case symbeg:
6049 DEBUG_PRINT ("EXECUTING symbeg.\n");
6051 /* We FAIL in one of the following cases: */
6053 /* Case 1: D is at the end of string. */
6054 if (AT_STRINGS_END (d))
6055 goto fail;
6056 else
6058 /* C1 is the character before D, S1 is the syntax of C1, C2
6059 is the character at D, and S2 is the syntax of C2. */
6060 re_wchar_t c1, c2;
6061 int s1, s2;
6062 #ifdef emacs
6063 ssize_t offset = PTR_TO_OFFSET (d);
6064 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
6065 UPDATE_SYNTAX_TABLE (charpos);
6066 #endif
6067 PREFETCH ();
6068 c2 = RE_STRING_CHAR (d, target_multibyte);
6069 s2 = SYNTAX (c2);
6071 /* Case 2: S2 is neither Sword nor Ssymbol. */
6072 if (s2 != Sword && s2 != Ssymbol)
6073 goto fail;
6075 /* Case 3: D is not at the beginning of string ... */
6076 if (!AT_STRINGS_BEG (d))
6078 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
6079 #ifdef emacs
6080 UPDATE_SYNTAX_TABLE_BACKWARD (charpos - 1);
6081 #endif
6082 s1 = SYNTAX (c1);
6084 /* ... and S1 is Sword or Ssymbol. */
6085 if (s1 == Sword || s1 == Ssymbol)
6086 goto fail;
6089 break;
6091 case symend:
6092 DEBUG_PRINT ("EXECUTING symend.\n");
6094 /* We FAIL in one of the following cases: */
6096 /* Case 1: D is at the beginning of string. */
6097 if (AT_STRINGS_BEG (d))
6098 goto fail;
6099 else
6101 /* C1 is the character before D, S1 is the syntax of C1, C2
6102 is the character at D, and S2 is the syntax of C2. */
6103 re_wchar_t c1, c2;
6104 int s1, s2;
6105 #ifdef emacs
6106 ssize_t offset = PTR_TO_OFFSET (d) - 1;
6107 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
6108 UPDATE_SYNTAX_TABLE (charpos);
6109 #endif
6110 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
6111 s1 = SYNTAX (c1);
6113 /* Case 2: S1 is neither Ssymbol nor Sword. */
6114 if (s1 != Sword && s1 != Ssymbol)
6115 goto fail;
6117 /* Case 3: D is not at the end of string ... */
6118 if (!AT_STRINGS_END (d))
6120 PREFETCH_NOLIMIT ();
6121 c2 = RE_STRING_CHAR (d, target_multibyte);
6122 #ifdef emacs
6123 UPDATE_SYNTAX_TABLE_FORWARD (charpos + 1);
6124 #endif
6125 s2 = SYNTAX (c2);
6127 /* ... and S2 is Sword or Ssymbol. */
6128 if (s2 == Sword || s2 == Ssymbol)
6129 goto fail;
6132 break;
6134 case syntaxspec:
6135 case notsyntaxspec:
6137 boolean not = (re_opcode_t) *(p - 1) == notsyntaxspec;
6138 mcnt = *p++;
6139 DEBUG_PRINT ("EXECUTING %ssyntaxspec %d.\n", not ? "not" : "",
6140 mcnt);
6141 PREFETCH ();
6142 #ifdef emacs
6144 ssize_t offset = PTR_TO_OFFSET (d);
6145 ssize_t pos1 = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
6146 UPDATE_SYNTAX_TABLE (pos1);
6148 #endif
6150 int len;
6151 re_wchar_t c;
6153 GET_CHAR_AFTER (c, d, len);
6154 if ((SYNTAX (c) != (enum syntaxcode) mcnt) ^ not)
6155 goto fail;
6156 d += len;
6159 break;
6161 #ifdef emacs
6162 case before_dot:
6163 DEBUG_PRINT ("EXECUTING before_dot.\n");
6164 if (PTR_BYTE_POS (d) >= PT_BYTE)
6165 goto fail;
6166 break;
6168 case at_dot:
6169 DEBUG_PRINT ("EXECUTING at_dot.\n");
6170 if (PTR_BYTE_POS (d) != PT_BYTE)
6171 goto fail;
6172 break;
6174 case after_dot:
6175 DEBUG_PRINT ("EXECUTING after_dot.\n");
6176 if (PTR_BYTE_POS (d) <= PT_BYTE)
6177 goto fail;
6178 break;
6180 case categoryspec:
6181 case notcategoryspec:
6183 boolean not = (re_opcode_t) *(p - 1) == notcategoryspec;
6184 mcnt = *p++;
6185 DEBUG_PRINT ("EXECUTING %scategoryspec %d.\n",
6186 not ? "not" : "", mcnt);
6187 PREFETCH ();
6190 int len;
6191 re_wchar_t c;
6192 GET_CHAR_AFTER (c, d, len);
6193 if ((!CHAR_HAS_CATEGORY (c, mcnt)) ^ not)
6194 goto fail;
6195 d += len;
6198 break;
6200 #endif /* emacs */
6202 default:
6203 abort ();
6205 continue; /* Successfully executed one pattern command; keep going. */
6208 /* We goto here if a matching operation fails. */
6209 fail:
6210 IMMEDIATE_QUIT_CHECK;
6211 if (!FAIL_STACK_EMPTY ())
6213 re_char *str, *pat;
6214 /* A restart point is known. Restore to that state. */
6215 DEBUG_PRINT ("\nFAIL:\n");
6216 POP_FAILURE_POINT (str, pat);
6217 switch (*pat++)
6219 case on_failure_keep_string_jump:
6220 assert (str == NULL);
6221 goto continue_failure_jump;
6223 case on_failure_jump_nastyloop:
6224 assert ((re_opcode_t)pat[-2] == no_op);
6225 PUSH_FAILURE_POINT (pat - 2, str);
6226 /* Fallthrough */
6228 case on_failure_jump_loop:
6229 case on_failure_jump:
6230 case succeed_n:
6231 d = str;
6232 continue_failure_jump:
6233 EXTRACT_NUMBER_AND_INCR (mcnt, pat);
6234 p = pat + mcnt;
6235 break;
6237 case no_op:
6238 /* A special frame used for nastyloops. */
6239 goto fail;
6241 default:
6242 abort ();
6245 assert (p >= bufp->buffer && p <= pend);
6247 if (d >= string1 && d <= end1)
6248 dend = end_match_1;
6250 else
6251 break; /* Matching at this starting point really fails. */
6252 } /* for (;;) */
6254 if (best_regs_set)
6255 goto restore_best_regs;
6257 FREE_VARIABLES ();
6259 return -1; /* Failure to match. */
6262 /* Subroutine definitions for re_match_2. */
6264 /* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
6265 bytes; nonzero otherwise. */
6267 static int
6268 bcmp_translate (const re_char *s1, const re_char *s2, register ssize_t len,
6269 RE_TRANSLATE_TYPE translate, const int target_multibyte)
6271 register re_char *p1 = s1, *p2 = s2;
6272 re_char *p1_end = s1 + len;
6273 re_char *p2_end = s2 + len;
6275 /* FIXME: Checking both p1 and p2 presumes that the two strings might have
6276 different lengths, but relying on a single `len' would break this. -sm */
6277 while (p1 < p1_end && p2 < p2_end)
6279 int p1_charlen, p2_charlen;
6280 re_wchar_t p1_ch, p2_ch;
6282 GET_CHAR_AFTER (p1_ch, p1, p1_charlen);
6283 GET_CHAR_AFTER (p2_ch, p2, p2_charlen);
6285 if (RE_TRANSLATE (translate, p1_ch)
6286 != RE_TRANSLATE (translate, p2_ch))
6287 return 1;
6289 p1 += p1_charlen, p2 += p2_charlen;
6292 if (p1 != p1_end || p2 != p2_end)
6293 return 1;
6295 return 0;
6298 /* Entry points for GNU code. */
6300 /* re_compile_pattern is the GNU regular expression compiler: it
6301 compiles PATTERN (of length SIZE) and puts the result in BUFP.
6302 Returns 0 if the pattern was valid, otherwise an error string.
6304 Assumes the `allocated' (and perhaps `buffer') and `translate' fields
6305 are set in BUFP on entry.
6307 We call regex_compile to do the actual compilation. */
6309 const char *
6310 re_compile_pattern (const char *pattern, size_t length,
6311 struct re_pattern_buffer *bufp)
6313 reg_errcode_t ret;
6315 /* GNU code is written to assume at least RE_NREGS registers will be set
6316 (and at least one extra will be -1). */
6317 bufp->regs_allocated = REGS_UNALLOCATED;
6319 /* And GNU code determines whether or not to get register information
6320 by passing null for the REGS argument to re_match, etc., not by
6321 setting no_sub. */
6322 bufp->no_sub = 0;
6324 ret = regex_compile ((re_char*) pattern, length, re_syntax_options, bufp);
6326 if (!ret)
6327 return NULL;
6328 return gettext (re_error_msgid[(int) ret]);
6330 WEAK_ALIAS (__re_compile_pattern, re_compile_pattern)
6332 /* Entry points compatible with 4.2 BSD regex library. We don't define
6333 them unless specifically requested. */
6335 #if defined _REGEX_RE_COMP || defined _LIBC
6337 /* BSD has one and only one pattern buffer. */
6338 static struct re_pattern_buffer re_comp_buf;
6340 char *
6341 # ifdef _LIBC
6342 /* Make these definitions weak in libc, so POSIX programs can redefine
6343 these names if they don't use our functions, and still use
6344 regcomp/regexec below without link errors. */
6345 weak_function
6346 # endif
6347 re_comp (const char *s)
6349 reg_errcode_t ret;
6351 if (!s)
6353 if (!re_comp_buf.buffer)
6354 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6355 return (char *) gettext ("No previous regular expression");
6356 return 0;
6359 if (!re_comp_buf.buffer)
6361 re_comp_buf.buffer = malloc (200);
6362 if (re_comp_buf.buffer == NULL)
6363 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6364 return (char *) gettext (re_error_msgid[(int) REG_ESPACE]);
6365 re_comp_buf.allocated = 200;
6367 re_comp_buf.fastmap = malloc (1 << BYTEWIDTH);
6368 if (re_comp_buf.fastmap == NULL)
6369 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6370 return (char *) gettext (re_error_msgid[(int) REG_ESPACE]);
6373 /* Since `re_exec' always passes NULL for the `regs' argument, we
6374 don't need to initialize the pattern buffer fields which affect it. */
6376 ret = regex_compile (s, strlen (s), re_syntax_options, &re_comp_buf);
6378 if (!ret)
6379 return NULL;
6381 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6382 return (char *) gettext (re_error_msgid[(int) ret]);
6387 # ifdef _LIBC
6388 weak_function
6389 # endif
6390 re_exec (const char *s)
6392 const size_t len = strlen (s);
6393 return (re_search (&re_comp_buf, s, len, 0, len, (struct re_registers *) 0)
6394 >= 0);
6396 #endif /* _REGEX_RE_COMP */
6398 /* POSIX.2 functions. Don't define these for Emacs. */
6400 #ifndef emacs
6402 /* regcomp takes a regular expression as a string and compiles it.
6404 PREG is a regex_t *. We do not expect any fields to be initialized,
6405 since POSIX says we shouldn't. Thus, we set
6407 `buffer' to the compiled pattern;
6408 `used' to the length of the compiled pattern;
6409 `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
6410 REG_EXTENDED bit in CFLAGS is set; otherwise, to
6411 RE_SYNTAX_POSIX_BASIC;
6412 `fastmap' to an allocated space for the fastmap;
6413 `fastmap_accurate' to zero;
6414 `re_nsub' to the number of subexpressions in PATTERN.
6416 PATTERN is the address of the pattern string.
6418 CFLAGS is a series of bits which affect compilation.
6420 If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
6421 use POSIX basic syntax.
6423 If REG_NEWLINE is set, then . and [^...] don't match newline.
6424 Also, regexec will try a match beginning after every newline.
6426 If REG_ICASE is set, then we considers upper- and lowercase
6427 versions of letters to be equivalent when matching.
6429 If REG_NOSUB is set, then when PREG is passed to regexec, that
6430 routine will report only success or failure, and nothing about the
6431 registers.
6433 It returns 0 if it succeeds, nonzero if it doesn't. (See regex.h for
6434 the return codes and their meanings.) */
6436 reg_errcode_t
6437 regcomp (regex_t *__restrict preg, const char *__restrict pattern,
6438 int cflags)
6440 reg_errcode_t ret;
6441 reg_syntax_t syntax
6442 = (cflags & REG_EXTENDED) ?
6443 RE_SYNTAX_POSIX_EXTENDED : RE_SYNTAX_POSIX_BASIC;
6445 /* regex_compile will allocate the space for the compiled pattern. */
6446 preg->buffer = 0;
6447 preg->allocated = 0;
6448 preg->used = 0;
6450 /* Try to allocate space for the fastmap. */
6451 preg->fastmap = malloc (1 << BYTEWIDTH);
6453 if (cflags & REG_ICASE)
6455 unsigned i;
6457 preg->translate = malloc (CHAR_SET_SIZE * sizeof *preg->translate);
6458 if (preg->translate == NULL)
6459 return (int) REG_ESPACE;
6461 /* Map uppercase characters to corresponding lowercase ones. */
6462 for (i = 0; i < CHAR_SET_SIZE; i++)
6463 preg->translate[i] = ISUPPER (i) ? TOLOWER (i) : i;
6465 else
6466 preg->translate = NULL;
6468 /* If REG_NEWLINE is set, newlines are treated differently. */
6469 if (cflags & REG_NEWLINE)
6470 { /* REG_NEWLINE implies neither . nor [^...] match newline. */
6471 syntax &= ~RE_DOT_NEWLINE;
6472 syntax |= RE_HAT_LISTS_NOT_NEWLINE;
6474 else
6475 syntax |= RE_NO_NEWLINE_ANCHOR;
6477 preg->no_sub = !!(cflags & REG_NOSUB);
6479 /* POSIX says a null character in the pattern terminates it, so we
6480 can use strlen here in compiling the pattern. */
6481 ret = regex_compile ((re_char*) pattern, strlen (pattern), syntax, preg);
6483 /* POSIX doesn't distinguish between an unmatched open-group and an
6484 unmatched close-group: both are REG_EPAREN. */
6485 if (ret == REG_ERPAREN)
6486 ret = REG_EPAREN;
6488 if (ret == REG_NOERROR && preg->fastmap)
6489 { /* Compute the fastmap now, since regexec cannot modify the pattern
6490 buffer. */
6491 re_compile_fastmap (preg);
6492 if (preg->can_be_null)
6493 { /* The fastmap can't be used anyway. */
6494 free (preg->fastmap);
6495 preg->fastmap = NULL;
6498 return ret;
6500 WEAK_ALIAS (__regcomp, regcomp)
6503 /* regexec searches for a given pattern, specified by PREG, in the
6504 string STRING.
6506 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
6507 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
6508 least NMATCH elements, and we set them to the offsets of the
6509 corresponding matched substrings.
6511 EFLAGS specifies `execution flags' which affect matching: if
6512 REG_NOTBOL is set, then ^ does not match at the beginning of the
6513 string; if REG_NOTEOL is set, then $ does not match at the end.
6515 We return 0 if we find a match and REG_NOMATCH if not. */
6517 reg_errcode_t
6518 regexec (const regex_t *__restrict preg, const char *__restrict string,
6519 size_t nmatch, regmatch_t pmatch[__restrict_arr], int eflags)
6521 regoff_t ret;
6522 struct re_registers regs;
6523 regex_t private_preg;
6524 size_t len = strlen (string);
6525 boolean want_reg_info = !preg->no_sub && nmatch > 0 && pmatch;
6527 private_preg = *preg;
6529 private_preg.not_bol = !!(eflags & REG_NOTBOL);
6530 private_preg.not_eol = !!(eflags & REG_NOTEOL);
6532 /* The user has told us exactly how many registers to return
6533 information about, via `nmatch'. We have to pass that on to the
6534 matching routines. */
6535 private_preg.regs_allocated = REGS_FIXED;
6537 if (want_reg_info)
6539 regs.num_regs = nmatch;
6540 regs.start = TALLOC (nmatch * 2, regoff_t);
6541 if (regs.start == NULL)
6542 return REG_NOMATCH;
6543 regs.end = regs.start + nmatch;
6546 /* Instead of using not_eol to implement REG_NOTEOL, we could simply
6547 pass (&private_preg, string, len + 1, 0, len, ...) pretending the string
6548 was a little bit longer but still only matching the real part.
6549 This works because the `endline' will check for a '\n' and will find a
6550 '\0', correctly deciding that this is not the end of a line.
6551 But it doesn't work out so nicely for REG_NOTBOL, since we don't have
6552 a convenient '\0' there. For all we know, the string could be preceded
6553 by '\n' which would throw things off. */
6555 /* Perform the searching operation. */
6556 ret = re_search (&private_preg, string, len,
6557 /* start: */ 0, /* range: */ len,
6558 want_reg_info ? &regs : (struct re_registers *) 0);
6560 /* Copy the register information to the POSIX structure. */
6561 if (want_reg_info)
6563 if (ret >= 0)
6565 unsigned r;
6567 for (r = 0; r < nmatch; r++)
6569 pmatch[r].rm_so = regs.start[r];
6570 pmatch[r].rm_eo = regs.end[r];
6574 /* If we needed the temporary register info, free the space now. */
6575 free (regs.start);
6578 /* We want zero return to mean success, unlike `re_search'. */
6579 return ret >= 0 ? REG_NOERROR : REG_NOMATCH;
6581 WEAK_ALIAS (__regexec, regexec)
6584 /* Returns a message corresponding to an error code, ERR_CODE, returned
6585 from either regcomp or regexec. We don't use PREG here.
6587 ERR_CODE was previously called ERRCODE, but that name causes an
6588 error with msvc8 compiler. */
6590 size_t
6591 regerror (int err_code, const regex_t *preg, char *errbuf, size_t errbuf_size)
6593 const char *msg;
6594 size_t msg_size;
6596 if (err_code < 0
6597 || err_code >= (sizeof (re_error_msgid) / sizeof (re_error_msgid[0])))
6598 /* Only error codes returned by the rest of the code should be passed
6599 to this routine. If we are given anything else, or if other regex
6600 code generates an invalid error code, then the program has a bug.
6601 Dump core so we can fix it. */
6602 abort ();
6604 msg = gettext (re_error_msgid[err_code]);
6606 msg_size = strlen (msg) + 1; /* Includes the null. */
6608 if (errbuf_size != 0)
6610 if (msg_size > errbuf_size)
6612 memcpy (errbuf, msg, errbuf_size - 1);
6613 errbuf[errbuf_size - 1] = 0;
6615 else
6616 strcpy (errbuf, msg);
6619 return msg_size;
6621 WEAK_ALIAS (__regerror, regerror)
6624 /* Free dynamically allocated space used by PREG. */
6626 void
6627 regfree (regex_t *preg)
6629 free (preg->buffer);
6630 preg->buffer = NULL;
6632 preg->allocated = 0;
6633 preg->used = 0;
6635 free (preg->fastmap);
6636 preg->fastmap = NULL;
6637 preg->fastmap_accurate = 0;
6639 free (preg->translate);
6640 preg->translate = NULL;
6642 WEAK_ALIAS (__regfree, regfree)
6644 #endif /* not emacs */