Bind grep-highlight-matches around the rgrep call
[emacs.git] / src / regex.c
blob38c5e350541942daefde69e5c54d1a89ef7a141a
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) 1993-2015 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__ + (6 <= __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 # include "syntax.h"
135 # include "category.h"
137 /* Make syntax table lookup grant data in gl_state. */
138 # define SYNTAX(c) syntax_property (c, 1)
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 MAX_MULTIBYTE_LENGTH 1
261 # define RE_MULTIBYTE_P(x) 0
262 # define RE_TARGET_MULTIBYTE_P(x) 0
263 # define WORD_BOUNDARY_P(c1, c2) (0)
264 # define BYTES_BY_CHAR_HEAD(p) (1)
265 # define PREV_CHAR_BOUNDARY(p, limit) ((p)--)
266 # define STRING_CHAR(p) (*(p))
267 # define RE_STRING_CHAR(p, multibyte) STRING_CHAR (p)
268 # define CHAR_STRING(c, s) (*(s) = (c), 1)
269 # define STRING_CHAR_AND_LENGTH(p, actual_len) ((actual_len) = 1, *(p))
270 # define RE_STRING_CHAR_AND_LENGTH(p, len, multibyte) STRING_CHAR_AND_LENGTH (p, len)
271 # define RE_CHAR_TO_MULTIBYTE(c) (c)
272 # define RE_CHAR_TO_UNIBYTE(c) (c)
273 # define GET_CHAR_BEFORE_2(c, p, str1, end1, str2, end2) \
274 (c = ((p) == (str2) ? *((end1) - 1) : *((p) - 1)))
275 # define GET_CHAR_AFTER(c, p, len) \
276 (c = *p, len = 1)
277 # define CHAR_BYTE8_P(c) (0)
278 # define CHAR_LEADING_CODE(c) (c)
280 #endif /* not emacs */
282 #ifndef RE_TRANSLATE
283 # define RE_TRANSLATE(TBL, C) ((unsigned char)(TBL)[C])
284 # define RE_TRANSLATE_P(TBL) (TBL)
285 #endif
287 /* Get the interface, including the syntax bits. */
288 #include "regex.h"
290 /* isalpha etc. are used for the character classes. */
291 #include <ctype.h>
293 #ifdef emacs
295 /* 1 if C is an ASCII character. */
296 # define IS_REAL_ASCII(c) ((c) < 0200)
298 /* 1 if C is a unibyte character. */
299 # define ISUNIBYTE(c) (SINGLE_BYTE_CHAR_P ((c)))
301 /* The Emacs definitions should not be directly affected by locales. */
303 /* In Emacs, these are only used for single-byte characters. */
304 # define ISDIGIT(c) ((c) >= '0' && (c) <= '9')
305 # define ISCNTRL(c) ((c) < ' ')
306 # define ISXDIGIT(c) (((c) >= '0' && (c) <= '9') \
307 || ((c) >= 'a' && (c) <= 'f') \
308 || ((c) >= 'A' && (c) <= 'F'))
310 /* This is only used for single-byte characters. */
311 # define ISBLANK(c) ((c) == ' ' || (c) == '\t')
313 /* The rest must handle multibyte characters. */
315 # define ISGRAPH(c) (SINGLE_BYTE_CHAR_P (c) \
316 ? (c) > ' ' && !((c) >= 0177 && (c) <= 0240) \
317 : graphicp (c))
319 # define ISPRINT(c) (SINGLE_BYTE_CHAR_P (c) \
320 ? (c) >= ' ' && !((c) >= 0177 && (c) <= 0237) \
321 : printablep (c))
323 # define ISALNUM(c) (IS_REAL_ASCII (c) \
324 ? (((c) >= 'a' && (c) <= 'z') \
325 || ((c) >= 'A' && (c) <= 'Z') \
326 || ((c) >= '0' && (c) <= '9')) \
327 : (alphabeticp (c) || decimalnump (c)))
329 # define ISALPHA(c) (IS_REAL_ASCII (c) \
330 ? (((c) >= 'a' && (c) <= 'z') \
331 || ((c) >= 'A' && (c) <= 'Z')) \
332 : alphabeticp (c))
334 # define ISLOWER(c) lowercasep (c)
336 # define ISPUNCT(c) (IS_REAL_ASCII (c) \
337 ? ((c) > ' ' && (c) < 0177 \
338 && !(((c) >= 'a' && (c) <= 'z') \
339 || ((c) >= 'A' && (c) <= 'Z') \
340 || ((c) >= '0' && (c) <= '9'))) \
341 : SYNTAX (c) != Sword)
343 # define ISSPACE(c) (SYNTAX (c) == Swhitespace)
345 # define ISUPPER(c) uppercasep (c)
347 # define ISWORD(c) (SYNTAX (c) == Sword)
349 #else /* not emacs */
351 /* 1 if C is an ASCII character. */
352 # define IS_REAL_ASCII(c) ((c) < 0200)
354 /* This distinction is not meaningful, except in Emacs. */
355 # define ISUNIBYTE(c) 1
357 # ifdef isblank
358 # define ISBLANK(c) isblank (c)
359 # else
360 # define ISBLANK(c) ((c) == ' ' || (c) == '\t')
361 # endif
362 # ifdef isgraph
363 # define ISGRAPH(c) isgraph (c)
364 # else
365 # define ISGRAPH(c) (isprint (c) && !isspace (c))
366 # endif
368 /* Solaris defines ISPRINT so we must undefine it first. */
369 # undef ISPRINT
370 # define ISPRINT(c) isprint (c)
371 # define ISDIGIT(c) isdigit (c)
372 # define ISALNUM(c) isalnum (c)
373 # define ISALPHA(c) isalpha (c)
374 # define ISCNTRL(c) iscntrl (c)
375 # define ISLOWER(c) islower (c)
376 # define ISPUNCT(c) ispunct (c)
377 # define ISSPACE(c) isspace (c)
378 # define ISUPPER(c) isupper (c)
379 # define ISXDIGIT(c) isxdigit (c)
381 # define ISWORD(c) ISALPHA (c)
383 # ifdef _tolower
384 # define TOLOWER(c) _tolower (c)
385 # else
386 # define TOLOWER(c) tolower (c)
387 # endif
389 /* How many characters in the character set. */
390 # define CHAR_SET_SIZE 256
392 # ifdef SYNTAX_TABLE
394 extern char *re_syntax_table;
396 # else /* not SYNTAX_TABLE */
398 static char re_syntax_table[CHAR_SET_SIZE];
400 static void
401 init_syntax_once (void)
403 register int c;
404 static int done = 0;
406 if (done)
407 return;
409 memset (re_syntax_table, 0, sizeof re_syntax_table);
411 for (c = 0; c < CHAR_SET_SIZE; ++c)
412 if (ISALNUM (c))
413 re_syntax_table[c] = Sword;
415 re_syntax_table['_'] = Ssymbol;
417 done = 1;
420 # endif /* not SYNTAX_TABLE */
422 # define SYNTAX(c) re_syntax_table[(c)]
424 #endif /* not emacs */
426 #define SIGN_EXTEND_CHAR(c) ((signed char) (c))
428 /* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we
429 use `alloca' instead of `malloc'. This is because using malloc in
430 re_search* or re_match* could cause memory leaks when C-g is used in
431 Emacs; also, malloc is slower and causes storage fragmentation. On
432 the other hand, malloc is more portable, and easier to debug.
434 Because we sometimes use alloca, some routines have to be macros,
435 not functions -- `alloca'-allocated space disappears at the end of the
436 function it is called in. */
438 #ifdef REGEX_MALLOC
440 # define REGEX_ALLOCATE malloc
441 # define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
442 # define REGEX_FREE free
444 #else /* not REGEX_MALLOC */
446 /* Emacs already defines alloca, sometimes. */
447 # ifndef alloca
449 /* Make alloca work the best possible way. */
450 # ifdef __GNUC__
451 # define alloca __builtin_alloca
452 # else /* not __GNUC__ */
453 # ifdef HAVE_ALLOCA_H
454 # include <alloca.h>
455 # endif /* HAVE_ALLOCA_H */
456 # endif /* not __GNUC__ */
458 # endif /* not alloca */
460 # ifdef emacs
461 # define REGEX_USE_SAFE_ALLOCA USE_SAFE_ALLOCA
462 # define REGEX_SAFE_FREE() SAFE_FREE ()
463 # define REGEX_ALLOCATE SAFE_ALLOCA
464 # else
465 # define REGEX_ALLOCATE alloca
466 # endif
468 /* Assumes a `char *destination' variable. */
469 # define REGEX_REALLOCATE(source, osize, nsize) \
470 (destination = REGEX_ALLOCATE (nsize), \
471 memcpy (destination, source, osize))
473 /* No need to do anything to free, after alloca. */
474 # define REGEX_FREE(arg) ((void)0) /* Do nothing! But inhibit gcc warning. */
476 #endif /* not REGEX_MALLOC */
478 #ifndef REGEX_USE_SAFE_ALLOCA
479 # define REGEX_USE_SAFE_ALLOCA ((void) 0)
480 # define REGEX_SAFE_FREE() ((void) 0)
481 #endif
483 /* Define how to allocate the failure stack. */
485 #if defined REL_ALLOC && defined REGEX_MALLOC
487 # define REGEX_ALLOCATE_STACK(size) \
488 r_alloc (&failure_stack_ptr, (size))
489 # define REGEX_REALLOCATE_STACK(source, osize, nsize) \
490 r_re_alloc (&failure_stack_ptr, (nsize))
491 # define REGEX_FREE_STACK(ptr) \
492 r_alloc_free (&failure_stack_ptr)
494 #else /* not using relocating allocator */
496 # define REGEX_ALLOCATE_STACK(size) REGEX_ALLOCATE (size)
497 # define REGEX_REALLOCATE_STACK(source, o, n) REGEX_REALLOCATE (source, o, n)
498 # define REGEX_FREE_STACK(ptr) REGEX_FREE (ptr)
500 #endif /* not using relocating allocator */
503 /* True if `size1' is non-NULL and PTR is pointing anywhere inside
504 `string1' or just past its end. This works if PTR is NULL, which is
505 a good thing. */
506 #define FIRST_STRING_P(ptr) \
507 (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
509 /* (Re)Allocate N items of type T using malloc, or fail. */
510 #define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
511 #define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
512 #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
514 #define BYTEWIDTH 8 /* In bits. */
516 #define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
518 #ifndef emacs
519 # undef max
520 # undef min
521 # define max(a, b) ((a) > (b) ? (a) : (b))
522 # define min(a, b) ((a) < (b) ? (a) : (b))
523 #endif
525 /* Type of source-pattern and string chars. */
526 #ifdef _MSC_VER
527 typedef unsigned char re_char;
528 typedef const re_char const_re_char;
529 #else
530 typedef const unsigned char re_char;
531 typedef re_char const_re_char;
532 #endif
534 typedef char boolean;
536 static regoff_t re_match_2_internal (struct re_pattern_buffer *bufp,
537 re_char *string1, size_t size1,
538 re_char *string2, size_t size2,
539 ssize_t pos,
540 struct re_registers *regs,
541 ssize_t stop);
543 /* These are the command codes that appear in compiled regular
544 expressions. Some opcodes are followed by argument bytes. A
545 command code can specify any interpretation whatsoever for its
546 arguments. Zero bytes may appear in the compiled regular expression. */
548 typedef enum
550 no_op = 0,
552 /* Succeed right away--no more backtracking. */
553 succeed,
555 /* Followed by one byte giving n, then by n literal bytes. */
556 exactn,
558 /* Matches any (more or less) character. */
559 anychar,
561 /* Matches any one char belonging to specified set. First
562 following byte is number of bitmap bytes. Then come bytes
563 for a bitmap saying which chars are in. Bits in each byte
564 are ordered low-bit-first. A character is in the set if its
565 bit is 1. A character too large to have a bit in the map is
566 automatically not in the set.
568 If the length byte has the 0x80 bit set, then that stuff
569 is followed by a range table:
570 2 bytes of flags for character sets (low 8 bits, high 8 bits)
571 See RANGE_TABLE_WORK_BITS below.
572 2 bytes, the number of pairs that follow (upto 32767)
573 pairs, each 2 multibyte characters,
574 each multibyte character represented as 3 bytes. */
575 charset,
577 /* Same parameters as charset, but match any character that is
578 not one of those specified. */
579 charset_not,
581 /* Start remembering the text that is matched, for storing in a
582 register. Followed by one byte with the register number, in
583 the range 0 to one less than the pattern buffer's re_nsub
584 field. */
585 start_memory,
587 /* Stop remembering the text that is matched and store it in a
588 memory register. Followed by one byte with the register
589 number, in the range 0 to one less than `re_nsub' in the
590 pattern buffer. */
591 stop_memory,
593 /* Match a duplicate of something remembered. Followed by one
594 byte containing the register number. */
595 duplicate,
597 /* Fail unless at beginning of line. */
598 begline,
600 /* Fail unless at end of line. */
601 endline,
603 /* Succeeds if at beginning of buffer (if emacs) or at beginning
604 of string to be matched (if not). */
605 begbuf,
607 /* Analogously, for end of buffer/string. */
608 endbuf,
610 /* Followed by two byte relative address to which to jump. */
611 jump,
613 /* Followed by two-byte relative address of place to resume at
614 in case of failure. */
615 on_failure_jump,
617 /* Like on_failure_jump, but pushes a placeholder instead of the
618 current string position when executed. */
619 on_failure_keep_string_jump,
621 /* Just like `on_failure_jump', except that it checks that we
622 don't get stuck in an infinite loop (matching an empty string
623 indefinitely). */
624 on_failure_jump_loop,
626 /* Just like `on_failure_jump_loop', except that it checks for
627 a different kind of loop (the kind that shows up with non-greedy
628 operators). This operation has to be immediately preceded
629 by a `no_op'. */
630 on_failure_jump_nastyloop,
632 /* A smart `on_failure_jump' used for greedy * and + operators.
633 It analyzes the loop before which it is put and if the
634 loop does not require backtracking, it changes itself to
635 `on_failure_keep_string_jump' and short-circuits the loop,
636 else it just defaults to changing itself into `on_failure_jump'.
637 It assumes that it is pointing to just past a `jump'. */
638 on_failure_jump_smart,
640 /* Followed by two-byte relative address and two-byte number n.
641 After matching N times, jump to the address upon failure.
642 Does not work if N starts at 0: use on_failure_jump_loop
643 instead. */
644 succeed_n,
646 /* Followed by two-byte relative address, and two-byte number n.
647 Jump to the address N times, then fail. */
648 jump_n,
650 /* Set the following two-byte relative address to the
651 subsequent two-byte number. The address *includes* the two
652 bytes of number. */
653 set_number_at,
655 wordbeg, /* Succeeds if at word beginning. */
656 wordend, /* Succeeds if at word end. */
658 wordbound, /* Succeeds if at a word boundary. */
659 notwordbound, /* Succeeds if not at a word boundary. */
661 symbeg, /* Succeeds if at symbol beginning. */
662 symend, /* Succeeds if at symbol end. */
664 /* Matches any character whose syntax is specified. Followed by
665 a byte which contains a syntax code, e.g., Sword. */
666 syntaxspec,
668 /* Matches any character whose syntax is not that specified. */
669 notsyntaxspec
671 #ifdef emacs
672 ,before_dot, /* Succeeds if before point. */
673 at_dot, /* Succeeds if at point. */
674 after_dot, /* Succeeds if after point. */
676 /* Matches any character whose category-set contains the specified
677 category. The operator is followed by a byte which contains a
678 category code (mnemonic ASCII character). */
679 categoryspec,
681 /* Matches any character whose category-set does not contain the
682 specified category. The operator is followed by a byte which
683 contains the category code (mnemonic ASCII character). */
684 notcategoryspec
685 #endif /* emacs */
686 } re_opcode_t;
688 /* Common operations on the compiled pattern. */
690 /* Store NUMBER in two contiguous bytes starting at DESTINATION. */
692 #define STORE_NUMBER(destination, number) \
693 do { \
694 (destination)[0] = (number) & 0377; \
695 (destination)[1] = (number) >> 8; \
696 } while (0)
698 /* Same as STORE_NUMBER, except increment DESTINATION to
699 the byte after where the number is stored. Therefore, DESTINATION
700 must be an lvalue. */
702 #define STORE_NUMBER_AND_INCR(destination, number) \
703 do { \
704 STORE_NUMBER (destination, number); \
705 (destination) += 2; \
706 } while (0)
708 /* Put into DESTINATION a number stored in two contiguous bytes starting
709 at SOURCE. */
711 #define EXTRACT_NUMBER(destination, source) \
712 ((destination) = extract_number (source))
714 static int
715 extract_number (re_char *source)
717 unsigned leading_byte = SIGN_EXTEND_CHAR (source[1]);
718 return (leading_byte << 8) + source[0];
721 /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
722 SOURCE must be an lvalue. */
724 #define EXTRACT_NUMBER_AND_INCR(destination, source) \
725 ((destination) = extract_number_and_incr (&source))
727 static int
728 extract_number_and_incr (re_char **source)
730 int num = extract_number (*source);
731 *source += 2;
732 return num;
735 /* Store a multibyte character in three contiguous bytes starting
736 DESTINATION, and increment DESTINATION to the byte after where the
737 character is stored. Therefore, DESTINATION must be an lvalue. */
739 #define STORE_CHARACTER_AND_INCR(destination, character) \
740 do { \
741 (destination)[0] = (character) & 0377; \
742 (destination)[1] = ((character) >> 8) & 0377; \
743 (destination)[2] = (character) >> 16; \
744 (destination) += 3; \
745 } while (0)
747 /* Put into DESTINATION a character stored in three contiguous bytes
748 starting at SOURCE. */
750 #define EXTRACT_CHARACTER(destination, source) \
751 do { \
752 (destination) = ((source)[0] \
753 | ((source)[1] << 8) \
754 | ((source)[2] << 16)); \
755 } while (0)
758 /* Macros for charset. */
760 /* Size of bitmap of charset P in bytes. P is a start of charset,
761 i.e. *P is (re_opcode_t) charset or (re_opcode_t) charset_not. */
762 #define CHARSET_BITMAP_SIZE(p) ((p)[1] & 0x7F)
764 /* Nonzero if charset P has range table. */
765 #define CHARSET_RANGE_TABLE_EXISTS_P(p) ((p)[1] & 0x80)
767 /* Return the address of range table of charset P. But not the start
768 of table itself, but the before where the number of ranges is
769 stored. `2 +' means to skip re_opcode_t and size of bitmap,
770 and the 2 bytes of flags at the start of the range table. */
771 #define CHARSET_RANGE_TABLE(p) (&(p)[4 + CHARSET_BITMAP_SIZE (p)])
773 #ifdef emacs
774 /* Extract the bit flags that start a range table. */
775 #define CHARSET_RANGE_TABLE_BITS(p) \
776 ((p)[2 + CHARSET_BITMAP_SIZE (p)] \
777 + (p)[3 + CHARSET_BITMAP_SIZE (p)] * 0x100)
778 #endif
780 /* Return the address of end of RANGE_TABLE. COUNT is number of
781 ranges (which is a pair of (start, end)) in the RANGE_TABLE. `* 2'
782 is start of range and end of range. `* 3' is size of each start
783 and end. */
784 #define CHARSET_RANGE_TABLE_END(range_table, count) \
785 ((range_table) + (count) * 2 * 3)
787 /* Test if C is in RANGE_TABLE. A flag NOT is negated if C is in.
788 COUNT is number of ranges in RANGE_TABLE. */
789 #define CHARSET_LOOKUP_RANGE_TABLE_RAW(not, c, range_table, count) \
790 do \
792 re_wchar_t range_start, range_end; \
793 re_char *rtp; \
794 re_char *range_table_end \
795 = CHARSET_RANGE_TABLE_END ((range_table), (count)); \
797 for (rtp = (range_table); rtp < range_table_end; rtp += 2 * 3) \
799 EXTRACT_CHARACTER (range_start, rtp); \
800 EXTRACT_CHARACTER (range_end, rtp + 3); \
802 if (range_start <= (c) && (c) <= range_end) \
804 (not) = !(not); \
805 break; \
809 while (0)
811 /* Test if C is in range table of CHARSET. The flag NOT is negated if
812 C is listed in it. */
813 #define CHARSET_LOOKUP_RANGE_TABLE(not, c, charset) \
814 do \
816 /* Number of ranges in range table. */ \
817 int count; \
818 re_char *range_table = CHARSET_RANGE_TABLE (charset); \
820 EXTRACT_NUMBER_AND_INCR (count, range_table); \
821 CHARSET_LOOKUP_RANGE_TABLE_RAW ((not), (c), range_table, count); \
823 while (0)
825 /* If DEBUG is defined, Regex prints many voluminous messages about what
826 it is doing (if the variable `debug' is nonzero). If linked with the
827 main program in `iregex.c', you can enter patterns and strings
828 interactively. And if linked with the main program in `main.c' and
829 the other test files, you can run the already-written tests. */
831 #ifdef DEBUG
833 /* We use standard I/O for debugging. */
834 # include <stdio.h>
836 /* It is useful to test things that ``must'' be true when debugging. */
837 # include <assert.h>
839 static int debug = -100000;
841 # define DEBUG_STATEMENT(e) e
842 # define DEBUG_PRINT(...) if (debug > 0) printf (__VA_ARGS__)
843 # define DEBUG_COMPILES_ARGUMENTS
844 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) \
845 if (debug > 0) print_partial_compiled_pattern (s, e)
846 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) \
847 if (debug > 0) print_double_string (w, s1, sz1, s2, sz2)
850 /* Print the fastmap in human-readable form. */
852 static void
853 print_fastmap (char *fastmap)
855 unsigned was_a_range = 0;
856 unsigned i = 0;
858 while (i < (1 << BYTEWIDTH))
860 if (fastmap[i++])
862 was_a_range = 0;
863 putchar (i - 1);
864 while (i < (1 << BYTEWIDTH) && fastmap[i])
866 was_a_range = 1;
867 i++;
869 if (was_a_range)
871 printf ("-");
872 putchar (i - 1);
876 putchar ('\n');
880 /* Print a compiled pattern string in human-readable form, starting at
881 the START pointer into it and ending just before the pointer END. */
883 static void
884 print_partial_compiled_pattern (re_char *start, re_char *end)
886 int mcnt, mcnt2;
887 re_char *p = start;
888 re_char *pend = end;
890 if (start == NULL)
892 fprintf (stderr, "(null)\n");
893 return;
896 /* Loop over pattern commands. */
897 while (p < pend)
899 fprintf (stderr, "%td:\t", p - start);
901 switch ((re_opcode_t) *p++)
903 case no_op:
904 fprintf (stderr, "/no_op");
905 break;
907 case succeed:
908 fprintf (stderr, "/succeed");
909 break;
911 case exactn:
912 mcnt = *p++;
913 fprintf (stderr, "/exactn/%d", mcnt);
916 fprintf (stderr, "/%c", *p++);
918 while (--mcnt);
919 break;
921 case start_memory:
922 fprintf (stderr, "/start_memory/%d", *p++);
923 break;
925 case stop_memory:
926 fprintf (stderr, "/stop_memory/%d", *p++);
927 break;
929 case duplicate:
930 fprintf (stderr, "/duplicate/%d", *p++);
931 break;
933 case anychar:
934 fprintf (stderr, "/anychar");
935 break;
937 case charset:
938 case charset_not:
940 register int c, last = -100;
941 register int in_range = 0;
942 int length = CHARSET_BITMAP_SIZE (p - 1);
943 int has_range_table = CHARSET_RANGE_TABLE_EXISTS_P (p - 1);
945 fprintf (stderr, "/charset [%s",
946 (re_opcode_t) *(p - 1) == charset_not ? "^" : "");
948 if (p + *p >= pend)
949 fprintf (stderr, " !extends past end of pattern! ");
951 for (c = 0; c < 256; c++)
952 if (c / 8 < length
953 && (p[1 + (c/8)] & (1 << (c % 8))))
955 /* Are we starting a range? */
956 if (last + 1 == c && ! in_range)
958 fprintf (stderr, "-");
959 in_range = 1;
961 /* Have we broken a range? */
962 else if (last + 1 != c && in_range)
964 fprintf (stderr, "%c", last);
965 in_range = 0;
968 if (! in_range)
969 fprintf (stderr, "%c", c);
971 last = c;
974 if (in_range)
975 fprintf (stderr, "%c", last);
977 fprintf (stderr, "]");
979 p += 1 + length;
981 if (has_range_table)
983 int count;
984 fprintf (stderr, "has-range-table");
986 /* ??? Should print the range table; for now, just skip it. */
987 p += 2; /* skip range table bits */
988 EXTRACT_NUMBER_AND_INCR (count, p);
989 p = CHARSET_RANGE_TABLE_END (p, count);
992 break;
994 case begline:
995 fprintf (stderr, "/begline");
996 break;
998 case endline:
999 fprintf (stderr, "/endline");
1000 break;
1002 case on_failure_jump:
1003 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1004 fprintf (stderr, "/on_failure_jump to %td", p + mcnt - start);
1005 break;
1007 case on_failure_keep_string_jump:
1008 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1009 fprintf (stderr, "/on_failure_keep_string_jump to %td",
1010 p + mcnt - start);
1011 break;
1013 case on_failure_jump_nastyloop:
1014 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1015 fprintf (stderr, "/on_failure_jump_nastyloop to %td",
1016 p + mcnt - start);
1017 break;
1019 case on_failure_jump_loop:
1020 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1021 fprintf (stderr, "/on_failure_jump_loop to %td",
1022 p + mcnt - start);
1023 break;
1025 case on_failure_jump_smart:
1026 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1027 fprintf (stderr, "/on_failure_jump_smart to %td",
1028 p + mcnt - start);
1029 break;
1031 case jump:
1032 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1033 fprintf (stderr, "/jump to %td", p + mcnt - start);
1034 break;
1036 case succeed_n:
1037 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1038 EXTRACT_NUMBER_AND_INCR (mcnt2, p);
1039 fprintf (stderr, "/succeed_n to %td, %d times",
1040 p - 2 + mcnt - start, mcnt2);
1041 break;
1043 case jump_n:
1044 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1045 EXTRACT_NUMBER_AND_INCR (mcnt2, p);
1046 fprintf (stderr, "/jump_n to %td, %d times",
1047 p - 2 + mcnt - start, mcnt2);
1048 break;
1050 case set_number_at:
1051 EXTRACT_NUMBER_AND_INCR (mcnt, p);
1052 EXTRACT_NUMBER_AND_INCR (mcnt2, p);
1053 fprintf (stderr, "/set_number_at location %td to %d",
1054 p - 2 + mcnt - start, mcnt2);
1055 break;
1057 case wordbound:
1058 fprintf (stderr, "/wordbound");
1059 break;
1061 case notwordbound:
1062 fprintf (stderr, "/notwordbound");
1063 break;
1065 case wordbeg:
1066 fprintf (stderr, "/wordbeg");
1067 break;
1069 case wordend:
1070 fprintf (stderr, "/wordend");
1071 break;
1073 case symbeg:
1074 fprintf (stderr, "/symbeg");
1075 break;
1077 case symend:
1078 fprintf (stderr, "/symend");
1079 break;
1081 case syntaxspec:
1082 fprintf (stderr, "/syntaxspec");
1083 mcnt = *p++;
1084 fprintf (stderr, "/%d", mcnt);
1085 break;
1087 case notsyntaxspec:
1088 fprintf (stderr, "/notsyntaxspec");
1089 mcnt = *p++;
1090 fprintf (stderr, "/%d", mcnt);
1091 break;
1093 # ifdef emacs
1094 case before_dot:
1095 fprintf (stderr, "/before_dot");
1096 break;
1098 case at_dot:
1099 fprintf (stderr, "/at_dot");
1100 break;
1102 case after_dot:
1103 fprintf (stderr, "/after_dot");
1104 break;
1106 case categoryspec:
1107 fprintf (stderr, "/categoryspec");
1108 mcnt = *p++;
1109 fprintf (stderr, "/%d", mcnt);
1110 break;
1112 case notcategoryspec:
1113 fprintf (stderr, "/notcategoryspec");
1114 mcnt = *p++;
1115 fprintf (stderr, "/%d", mcnt);
1116 break;
1117 # endif /* emacs */
1119 case begbuf:
1120 fprintf (stderr, "/begbuf");
1121 break;
1123 case endbuf:
1124 fprintf (stderr, "/endbuf");
1125 break;
1127 default:
1128 fprintf (stderr, "?%d", *(p-1));
1131 fprintf (stderr, "\n");
1134 fprintf (stderr, "%td:\tend of pattern.\n", p - start);
1138 static void
1139 print_compiled_pattern (struct re_pattern_buffer *bufp)
1141 re_char *buffer = bufp->buffer;
1143 print_partial_compiled_pattern (buffer, buffer + bufp->used);
1144 printf ("%ld bytes used/%ld bytes allocated.\n",
1145 bufp->used, bufp->allocated);
1147 if (bufp->fastmap_accurate && bufp->fastmap)
1149 printf ("fastmap: ");
1150 print_fastmap (bufp->fastmap);
1153 printf ("re_nsub: %zu\t", bufp->re_nsub);
1154 printf ("regs_alloc: %d\t", bufp->regs_allocated);
1155 printf ("can_be_null: %d\t", bufp->can_be_null);
1156 printf ("no_sub: %d\t", bufp->no_sub);
1157 printf ("not_bol: %d\t", bufp->not_bol);
1158 printf ("not_eol: %d\t", bufp->not_eol);
1159 printf ("syntax: %lx\n", bufp->syntax);
1160 fflush (stdout);
1161 /* Perhaps we should print the translate table? */
1165 static void
1166 print_double_string (re_char *where, re_char *string1, ssize_t size1,
1167 re_char *string2, ssize_t size2)
1169 ssize_t this_char;
1171 if (where == NULL)
1172 printf ("(null)");
1173 else
1175 if (FIRST_STRING_P (where))
1177 for (this_char = where - string1; this_char < size1; this_char++)
1178 putchar (string1[this_char]);
1180 where = string2;
1183 for (this_char = where - string2; this_char < size2; this_char++)
1184 putchar (string2[this_char]);
1188 #else /* not DEBUG */
1190 # undef assert
1191 # define assert(e)
1193 # define DEBUG_STATEMENT(e)
1194 # define DEBUG_PRINT(...)
1195 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
1196 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
1198 #endif /* not DEBUG */
1200 /* Use this to suppress gcc's `...may be used before initialized' warnings. */
1201 #ifdef lint
1202 # define IF_LINT(Code) Code
1203 #else
1204 # define IF_LINT(Code) /* empty */
1205 #endif
1207 /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
1208 also be assigned to arbitrarily: each pattern buffer stores its own
1209 syntax, so it can be changed between regex compilations. */
1210 /* This has no initializer because initialized variables in Emacs
1211 become read-only after dumping. */
1212 reg_syntax_t re_syntax_options;
1215 /* Specify the precise syntax of regexps for compilation. This provides
1216 for compatibility for various utilities which historically have
1217 different, incompatible syntaxes.
1219 The argument SYNTAX is a bit mask comprised of the various bits
1220 defined in regex.h. We return the old syntax. */
1222 reg_syntax_t
1223 re_set_syntax (reg_syntax_t syntax)
1225 reg_syntax_t ret = re_syntax_options;
1227 re_syntax_options = syntax;
1228 return ret;
1230 WEAK_ALIAS (__re_set_syntax, re_set_syntax)
1232 /* Regexp to use to replace spaces, or NULL meaning don't. */
1233 static const_re_char *whitespace_regexp;
1235 void
1236 re_set_whitespace_regexp (const char *regexp)
1238 whitespace_regexp = (const_re_char *) regexp;
1240 WEAK_ALIAS (__re_set_syntax, re_set_syntax)
1242 /* This table gives an error message for each of the error codes listed
1243 in regex.h. Obviously the order here has to be same as there.
1244 POSIX doesn't require that we do anything for REG_NOERROR,
1245 but why not be nice? */
1247 static const char *re_error_msgid[] =
1249 gettext_noop ("Success"), /* REG_NOERROR */
1250 gettext_noop ("No match"), /* REG_NOMATCH */
1251 gettext_noop ("Invalid regular expression"), /* REG_BADPAT */
1252 gettext_noop ("Invalid collation character"), /* REG_ECOLLATE */
1253 gettext_noop ("Invalid character class name"), /* REG_ECTYPE */
1254 gettext_noop ("Trailing backslash"), /* REG_EESCAPE */
1255 gettext_noop ("Invalid back reference"), /* REG_ESUBREG */
1256 gettext_noop ("Unmatched [ or [^"), /* REG_EBRACK */
1257 gettext_noop ("Unmatched ( or \\("), /* REG_EPAREN */
1258 gettext_noop ("Unmatched \\{"), /* REG_EBRACE */
1259 gettext_noop ("Invalid content of \\{\\}"), /* REG_BADBR */
1260 gettext_noop ("Invalid range end"), /* REG_ERANGE */
1261 gettext_noop ("Memory exhausted"), /* REG_ESPACE */
1262 gettext_noop ("Invalid preceding regular expression"), /* REG_BADRPT */
1263 gettext_noop ("Premature end of regular expression"), /* REG_EEND */
1264 gettext_noop ("Regular expression too big"), /* REG_ESIZE */
1265 gettext_noop ("Unmatched ) or \\)"), /* REG_ERPAREN */
1266 gettext_noop ("Range striding over charsets") /* REG_ERANGEX */
1269 /* Avoiding alloca during matching, to placate r_alloc. */
1271 /* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
1272 searching and matching functions should not call alloca. On some
1273 systems, alloca is implemented in terms of malloc, and if we're
1274 using the relocating allocator routines, then malloc could cause a
1275 relocation, which might (if the strings being searched are in the
1276 ralloc heap) shift the data out from underneath the regexp
1277 routines.
1279 Here's another reason to avoid allocation: Emacs
1280 processes input from X in a signal handler; processing X input may
1281 call malloc; if input arrives while a matching routine is calling
1282 malloc, then we're scrod. But Emacs can't just block input while
1283 calling matching routines; then we don't notice interrupts when
1284 they come in. So, Emacs blocks input around all regexp calls
1285 except the matching calls, which it leaves unprotected, in the
1286 faith that they will not malloc. */
1288 /* Normally, this is fine. */
1289 #define MATCH_MAY_ALLOCATE
1291 /* The match routines may not allocate if (1) they would do it with malloc
1292 and (2) it's not safe for them to use malloc.
1293 Note that if REL_ALLOC is defined, matching would not use malloc for the
1294 failure stack, but we would still use it for the register vectors;
1295 so REL_ALLOC should not affect this. */
1296 #if defined REGEX_MALLOC && defined emacs
1297 # undef MATCH_MAY_ALLOCATE
1298 #endif
1301 /* Failure stack declarations and macros; both re_compile_fastmap and
1302 re_match_2 use a failure stack. These have to be macros because of
1303 REGEX_ALLOCATE_STACK. */
1306 /* Approximate number of failure points for which to initially allocate space
1307 when matching. If this number is exceeded, we allocate more
1308 space, so it is not a hard limit. */
1309 #ifndef INIT_FAILURE_ALLOC
1310 # define INIT_FAILURE_ALLOC 20
1311 #endif
1313 /* Roughly the maximum number of failure points on the stack. Would be
1314 exactly that if always used TYPICAL_FAILURE_SIZE items each time we failed.
1315 This is a variable only so users of regex can assign to it; we never
1316 change it ourselves. We always multiply it by TYPICAL_FAILURE_SIZE
1317 before using it, so it should probably be a byte-count instead. */
1318 # if defined MATCH_MAY_ALLOCATE
1319 /* Note that 4400 was enough to cause a crash on Alpha OSF/1,
1320 whose default stack limit is 2mb. In order for a larger
1321 value to work reliably, you have to try to make it accord
1322 with the process stack limit. */
1323 size_t re_max_failures = 40000;
1324 # else
1325 size_t re_max_failures = 4000;
1326 # endif
1328 union fail_stack_elt
1330 re_char *pointer;
1331 /* This should be the biggest `int' that's no bigger than a pointer. */
1332 long integer;
1335 typedef union fail_stack_elt fail_stack_elt_t;
1337 typedef struct
1339 fail_stack_elt_t *stack;
1340 size_t size;
1341 size_t avail; /* Offset of next open position. */
1342 size_t frame; /* Offset of the cur constructed frame. */
1343 } fail_stack_type;
1345 #define FAIL_STACK_EMPTY() (fail_stack.frame == 0)
1348 /* Define macros to initialize and free the failure stack.
1349 Do `return -2' if the alloc fails. */
1351 #ifdef MATCH_MAY_ALLOCATE
1352 # define INIT_FAIL_STACK() \
1353 do { \
1354 fail_stack.stack = \
1355 REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * TYPICAL_FAILURE_SIZE \
1356 * sizeof (fail_stack_elt_t)); \
1358 if (fail_stack.stack == NULL) \
1359 return -2; \
1361 fail_stack.size = INIT_FAILURE_ALLOC; \
1362 fail_stack.avail = 0; \
1363 fail_stack.frame = 0; \
1364 } while (0)
1365 #else
1366 # define INIT_FAIL_STACK() \
1367 do { \
1368 fail_stack.avail = 0; \
1369 fail_stack.frame = 0; \
1370 } while (0)
1372 # define RETALLOC_IF(addr, n, t) \
1373 if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
1374 #endif
1377 /* Double the size of FAIL_STACK, up to a limit
1378 which allows approximately `re_max_failures' items.
1380 Return 1 if succeeds, and 0 if either ran out of memory
1381 allocating space for it or it was already too large.
1383 REGEX_REALLOCATE_STACK requires `destination' be declared. */
1385 /* Factor to increase the failure stack size by
1386 when we increase it.
1387 This used to be 2, but 2 was too wasteful
1388 because the old discarded stacks added up to as much space
1389 were as ultimate, maximum-size stack. */
1390 #define FAIL_STACK_GROWTH_FACTOR 4
1392 #define GROW_FAIL_STACK(fail_stack) \
1393 (((fail_stack).size * sizeof (fail_stack_elt_t) \
1394 >= re_max_failures * TYPICAL_FAILURE_SIZE) \
1395 ? 0 \
1396 : ((fail_stack).stack \
1397 = REGEX_REALLOCATE_STACK ((fail_stack).stack, \
1398 (fail_stack).size * sizeof (fail_stack_elt_t), \
1399 min (re_max_failures * TYPICAL_FAILURE_SIZE, \
1400 ((fail_stack).size * sizeof (fail_stack_elt_t) \
1401 * FAIL_STACK_GROWTH_FACTOR))), \
1403 (fail_stack).stack == NULL \
1404 ? 0 \
1405 : ((fail_stack).size \
1406 = (min (re_max_failures * TYPICAL_FAILURE_SIZE, \
1407 ((fail_stack).size * sizeof (fail_stack_elt_t) \
1408 * FAIL_STACK_GROWTH_FACTOR)) \
1409 / sizeof (fail_stack_elt_t)), \
1410 1)))
1413 /* Push a pointer value onto the failure stack.
1414 Assumes the variable `fail_stack'. Probably should only
1415 be called from within `PUSH_FAILURE_POINT'. */
1416 #define PUSH_FAILURE_POINTER(item) \
1417 fail_stack.stack[fail_stack.avail++].pointer = (item)
1419 /* This pushes an integer-valued item 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_INT(item) \
1423 fail_stack.stack[fail_stack.avail++].integer = (item)
1425 /* These POP... operations complement the PUSH... operations.
1426 All assume that `fail_stack' is nonempty. */
1427 #define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
1428 #define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
1430 /* Individual items aside from the registers. */
1431 #define NUM_NONREG_ITEMS 3
1433 /* Used to examine the stack (to detect infinite loops). */
1434 #define FAILURE_PAT(h) fail_stack.stack[(h) - 1].pointer
1435 #define FAILURE_STR(h) (fail_stack.stack[(h) - 2].pointer)
1436 #define NEXT_FAILURE_HANDLE(h) fail_stack.stack[(h) - 3].integer
1437 #define TOP_FAILURE_HANDLE() fail_stack.frame
1440 #define ENSURE_FAIL_STACK(space) \
1441 while (REMAINING_AVAIL_SLOTS <= space) { \
1442 if (!GROW_FAIL_STACK (fail_stack)) \
1443 return -2; \
1444 DEBUG_PRINT ("\n Doubled stack; size now: %zd\n", (fail_stack).size);\
1445 DEBUG_PRINT (" slots available: %zd\n", REMAINING_AVAIL_SLOTS);\
1448 /* Push register NUM onto the stack. */
1449 #define PUSH_FAILURE_REG(num) \
1450 do { \
1451 char *destination; \
1452 long n = num; \
1453 ENSURE_FAIL_STACK(3); \
1454 DEBUG_PRINT (" Push reg %ld (spanning %p -> %p)\n", \
1455 n, regstart[n], regend[n]); \
1456 PUSH_FAILURE_POINTER (regstart[n]); \
1457 PUSH_FAILURE_POINTER (regend[n]); \
1458 PUSH_FAILURE_INT (n); \
1459 } while (0)
1461 /* Change the counter's value to VAL, but make sure that it will
1462 be reset when backtracking. */
1463 #define PUSH_NUMBER(ptr,val) \
1464 do { \
1465 char *destination; \
1466 int c; \
1467 ENSURE_FAIL_STACK(3); \
1468 EXTRACT_NUMBER (c, ptr); \
1469 DEBUG_PRINT (" Push number %p = %d -> %d\n", ptr, c, val); \
1470 PUSH_FAILURE_INT (c); \
1471 PUSH_FAILURE_POINTER (ptr); \
1472 PUSH_FAILURE_INT (-1); \
1473 STORE_NUMBER (ptr, val); \
1474 } while (0)
1476 /* Pop a saved register off the stack. */
1477 #define POP_FAILURE_REG_OR_COUNT() \
1478 do { \
1479 long pfreg = POP_FAILURE_INT (); \
1480 if (pfreg == -1) \
1482 /* It's a counter. */ \
1483 /* Here, we discard `const', making re_match non-reentrant. */ \
1484 unsigned char *ptr = (unsigned char*) POP_FAILURE_POINTER (); \
1485 pfreg = POP_FAILURE_INT (); \
1486 STORE_NUMBER (ptr, pfreg); \
1487 DEBUG_PRINT (" Pop counter %p = %ld\n", ptr, pfreg); \
1489 else \
1491 regend[pfreg] = POP_FAILURE_POINTER (); \
1492 regstart[pfreg] = POP_FAILURE_POINTER (); \
1493 DEBUG_PRINT (" Pop reg %ld (spanning %p -> %p)\n", \
1494 pfreg, regstart[pfreg], regend[pfreg]); \
1496 } while (0)
1498 /* Check that we are not stuck in an infinite loop. */
1499 #define CHECK_INFINITE_LOOP(pat_cur, string_place) \
1500 do { \
1501 ssize_t failure = TOP_FAILURE_HANDLE (); \
1502 /* Check for infinite matching loops */ \
1503 while (failure > 0 \
1504 && (FAILURE_STR (failure) == string_place \
1505 || FAILURE_STR (failure) == NULL)) \
1507 assert (FAILURE_PAT (failure) >= bufp->buffer \
1508 && FAILURE_PAT (failure) <= bufp->buffer + bufp->used); \
1509 if (FAILURE_PAT (failure) == pat_cur) \
1511 cycle = 1; \
1512 break; \
1514 DEBUG_PRINT (" Other pattern: %p\n", FAILURE_PAT (failure)); \
1515 failure = NEXT_FAILURE_HANDLE(failure); \
1517 DEBUG_PRINT (" Other string: %p\n", FAILURE_STR (failure)); \
1518 } while (0)
1520 /* Push the information about the state we will need
1521 if we ever fail back to it.
1523 Requires variables fail_stack, regstart, regend and
1524 num_regs be declared. GROW_FAIL_STACK requires `destination' be
1525 declared.
1527 Does `return FAILURE_CODE' if runs out of memory. */
1529 #define PUSH_FAILURE_POINT(pattern, string_place) \
1530 do { \
1531 char *destination; \
1532 /* Must be int, so when we don't save any registers, the arithmetic \
1533 of 0 + -1 isn't done as unsigned. */ \
1535 DEBUG_STATEMENT (nfailure_points_pushed++); \
1536 DEBUG_PRINT ("\nPUSH_FAILURE_POINT:\n"); \
1537 DEBUG_PRINT (" Before push, next avail: %zd\n", (fail_stack).avail); \
1538 DEBUG_PRINT (" size: %zd\n", (fail_stack).size);\
1540 ENSURE_FAIL_STACK (NUM_NONREG_ITEMS); \
1542 DEBUG_PRINT ("\n"); \
1544 DEBUG_PRINT (" Push frame index: %zd\n", fail_stack.frame); \
1545 PUSH_FAILURE_INT (fail_stack.frame); \
1547 DEBUG_PRINT (" Push string %p: `", string_place); \
1548 DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2, size2);\
1549 DEBUG_PRINT ("'\n"); \
1550 PUSH_FAILURE_POINTER (string_place); \
1552 DEBUG_PRINT (" Push pattern %p: ", pattern); \
1553 DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern, pend); \
1554 PUSH_FAILURE_POINTER (pattern); \
1556 /* Close the frame by moving the frame pointer past it. */ \
1557 fail_stack.frame = fail_stack.avail; \
1558 } while (0)
1560 /* Estimate the size of data pushed by a typical failure stack entry.
1561 An estimate is all we need, because all we use this for
1562 is to choose a limit for how big to make the failure stack. */
1563 /* BEWARE, the value `20' is hard-coded in emacs.c:main(). */
1564 #define TYPICAL_FAILURE_SIZE 20
1566 /* How many items can still be added to the stack without overflowing it. */
1567 #define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
1570 /* Pops what PUSH_FAIL_STACK pushes.
1572 We restore into the parameters, all of which should be lvalues:
1573 STR -- the saved data position.
1574 PAT -- the saved pattern position.
1575 REGSTART, REGEND -- arrays of string positions.
1577 Also assumes the variables `fail_stack' and (if debugging), `bufp',
1578 `pend', `string1', `size1', `string2', and `size2'. */
1580 #define POP_FAILURE_POINT(str, pat) \
1581 do { \
1582 assert (!FAIL_STACK_EMPTY ()); \
1584 /* Remove failure points and point to how many regs pushed. */ \
1585 DEBUG_PRINT ("POP_FAILURE_POINT:\n"); \
1586 DEBUG_PRINT (" Before pop, next avail: %zd\n", fail_stack.avail); \
1587 DEBUG_PRINT (" size: %zd\n", fail_stack.size); \
1589 /* Pop the saved registers. */ \
1590 while (fail_stack.frame < fail_stack.avail) \
1591 POP_FAILURE_REG_OR_COUNT (); \
1593 pat = POP_FAILURE_POINTER (); \
1594 DEBUG_PRINT (" Popping pattern %p: ", pat); \
1595 DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend); \
1597 /* If the saved string location is NULL, it came from an \
1598 on_failure_keep_string_jump opcode, and we want to throw away the \
1599 saved NULL, thus retaining our current position in the string. */ \
1600 str = POP_FAILURE_POINTER (); \
1601 DEBUG_PRINT (" Popping string %p: `", str); \
1602 DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2); \
1603 DEBUG_PRINT ("'\n"); \
1605 fail_stack.frame = POP_FAILURE_INT (); \
1606 DEBUG_PRINT (" Popping frame index: %zd\n", fail_stack.frame); \
1608 assert (fail_stack.avail >= 0); \
1609 assert (fail_stack.frame <= fail_stack.avail); \
1611 DEBUG_STATEMENT (nfailure_points_popped++); \
1612 } while (0) /* POP_FAILURE_POINT */
1616 /* Registers are set to a sentinel when they haven't yet matched. */
1617 #define REG_UNSET(e) ((e) == NULL)
1619 /* Subroutine declarations and macros for regex_compile. */
1621 static reg_errcode_t regex_compile (re_char *pattern, size_t size,
1622 reg_syntax_t syntax,
1623 struct re_pattern_buffer *bufp);
1624 static void store_op1 (re_opcode_t op, unsigned char *loc, int arg);
1625 static void store_op2 (re_opcode_t op, unsigned char *loc, int arg1, int arg2);
1626 static void insert_op1 (re_opcode_t op, unsigned char *loc,
1627 int arg, unsigned char *end);
1628 static void insert_op2 (re_opcode_t op, unsigned char *loc,
1629 int arg1, int arg2, unsigned char *end);
1630 static boolean at_begline_loc_p (re_char *pattern, re_char *p,
1631 reg_syntax_t syntax);
1632 static boolean at_endline_loc_p (re_char *p, re_char *pend,
1633 reg_syntax_t syntax);
1634 static re_char *skip_one_char (re_char *p);
1635 static int analyze_first (re_char *p, re_char *pend,
1636 char *fastmap, const int multibyte);
1638 /* Fetch the next character in the uncompiled pattern, with no
1639 translation. */
1640 #define PATFETCH(c) \
1641 do { \
1642 int len; \
1643 if (p == pend) return REG_EEND; \
1644 c = RE_STRING_CHAR_AND_LENGTH (p, len, multibyte); \
1645 p += len; \
1646 } while (0)
1649 /* If `translate' is non-null, return translate[D], else just D. We
1650 cast the subscript to translate because some data is declared as
1651 `char *', to avoid warnings when a string constant is passed. But
1652 when we use a character as a subscript we must make it unsigned. */
1653 #ifndef TRANSLATE
1654 # define TRANSLATE(d) \
1655 (RE_TRANSLATE_P (translate) ? RE_TRANSLATE (translate, (d)) : (d))
1656 #endif
1659 /* Macros for outputting the compiled pattern into `buffer'. */
1661 /* If the buffer isn't allocated when it comes in, use this. */
1662 #define INIT_BUF_SIZE 32
1664 /* Make sure we have at least N more bytes of space in buffer. */
1665 #define GET_BUFFER_SPACE(n) \
1666 while ((size_t) (b - bufp->buffer + (n)) > bufp->allocated) \
1667 EXTEND_BUFFER ()
1669 /* Make sure we have one more byte of buffer space and then add C to it. */
1670 #define BUF_PUSH(c) \
1671 do { \
1672 GET_BUFFER_SPACE (1); \
1673 *b++ = (unsigned char) (c); \
1674 } while (0)
1677 /* Ensure we have two more bytes of buffer space and then append C1 and C2. */
1678 #define BUF_PUSH_2(c1, c2) \
1679 do { \
1680 GET_BUFFER_SPACE (2); \
1681 *b++ = (unsigned char) (c1); \
1682 *b++ = (unsigned char) (c2); \
1683 } while (0)
1686 /* Store a jump with opcode OP at LOC to location TO. We store a
1687 relative address offset by the three bytes the jump itself occupies. */
1688 #define STORE_JUMP(op, loc, to) \
1689 store_op1 (op, loc, (to) - (loc) - 3)
1691 /* Likewise, for a two-argument jump. */
1692 #define STORE_JUMP2(op, loc, to, arg) \
1693 store_op2 (op, loc, (to) - (loc) - 3, arg)
1695 /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
1696 #define INSERT_JUMP(op, loc, to) \
1697 insert_op1 (op, loc, (to) - (loc) - 3, b)
1699 /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
1700 #define INSERT_JUMP2(op, loc, to, arg) \
1701 insert_op2 (op, loc, (to) - (loc) - 3, arg, b)
1704 /* This is not an arbitrary limit: the arguments which represent offsets
1705 into the pattern are two bytes long. So if 2^15 bytes turns out to
1706 be too small, many things would have to change. */
1707 # define MAX_BUF_SIZE (1L << 15)
1709 /* Extend the buffer by twice its current size via realloc and
1710 reset the pointers that pointed into the old block to point to the
1711 correct places in the new one. If extending the buffer results in it
1712 being larger than MAX_BUF_SIZE, then flag memory exhausted. */
1713 #if __BOUNDED_POINTERS__
1714 # define SET_HIGH_BOUND(P) (__ptrhigh (P) = __ptrlow (P) + bufp->allocated)
1715 # define MOVE_BUFFER_POINTER(P) \
1716 (__ptrlow (P) = new_buffer + (__ptrlow (P) - old_buffer), \
1717 SET_HIGH_BOUND (P), \
1718 __ptrvalue (P) = new_buffer + (__ptrvalue (P) - old_buffer))
1719 # define ELSE_EXTEND_BUFFER_HIGH_BOUND \
1720 else \
1722 SET_HIGH_BOUND (b); \
1723 SET_HIGH_BOUND (begalt); \
1724 if (fixup_alt_jump) \
1725 SET_HIGH_BOUND (fixup_alt_jump); \
1726 if (laststart) \
1727 SET_HIGH_BOUND (laststart); \
1728 if (pending_exact) \
1729 SET_HIGH_BOUND (pending_exact); \
1731 #else
1732 # define MOVE_BUFFER_POINTER(P) ((P) = new_buffer + ((P) - old_buffer))
1733 # define ELSE_EXTEND_BUFFER_HIGH_BOUND
1734 #endif
1735 #define EXTEND_BUFFER() \
1736 do { \
1737 unsigned char *old_buffer = bufp->buffer; \
1738 if (bufp->allocated == MAX_BUF_SIZE) \
1739 return REG_ESIZE; \
1740 bufp->allocated <<= 1; \
1741 if (bufp->allocated > MAX_BUF_SIZE) \
1742 bufp->allocated = MAX_BUF_SIZE; \
1743 RETALLOC (bufp->buffer, bufp->allocated, unsigned char); \
1744 if (bufp->buffer == NULL) \
1745 return REG_ESPACE; \
1746 /* If the buffer moved, move all the pointers into it. */ \
1747 if (old_buffer != bufp->buffer) \
1749 unsigned char *new_buffer = bufp->buffer; \
1750 MOVE_BUFFER_POINTER (b); \
1751 MOVE_BUFFER_POINTER (begalt); \
1752 if (fixup_alt_jump) \
1753 MOVE_BUFFER_POINTER (fixup_alt_jump); \
1754 if (laststart) \
1755 MOVE_BUFFER_POINTER (laststart); \
1756 if (pending_exact) \
1757 MOVE_BUFFER_POINTER (pending_exact); \
1759 ELSE_EXTEND_BUFFER_HIGH_BOUND \
1760 } while (0)
1763 /* Since we have one byte reserved for the register number argument to
1764 {start,stop}_memory, the maximum number of groups we can report
1765 things about is what fits in that byte. */
1766 #define MAX_REGNUM 255
1768 /* But patterns can have more than `MAX_REGNUM' registers. We just
1769 ignore the excess. */
1770 typedef int regnum_t;
1773 /* Macros for the compile stack. */
1775 /* Since offsets can go either forwards or backwards, this type needs to
1776 be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
1777 /* int may be not enough when sizeof(int) == 2. */
1778 typedef long pattern_offset_t;
1780 typedef struct
1782 pattern_offset_t begalt_offset;
1783 pattern_offset_t fixup_alt_jump;
1784 pattern_offset_t laststart_offset;
1785 regnum_t regnum;
1786 } compile_stack_elt_t;
1789 typedef struct
1791 compile_stack_elt_t *stack;
1792 size_t size;
1793 size_t avail; /* Offset of next open position. */
1794 } compile_stack_type;
1797 #define INIT_COMPILE_STACK_SIZE 32
1799 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
1800 #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
1802 /* The next available element. */
1803 #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
1805 /* Explicit quit checking is needed for Emacs, which uses polling to
1806 process input events. */
1807 #ifdef emacs
1808 # define IMMEDIATE_QUIT_CHECK \
1809 do { \
1810 if (immediate_quit) QUIT; \
1811 } while (0)
1812 #else
1813 # define IMMEDIATE_QUIT_CHECK ((void)0)
1814 #endif
1816 /* Structure to manage work area for range table. */
1817 struct range_table_work_area
1819 int *table; /* actual work area. */
1820 int allocated; /* allocated size for work area in bytes. */
1821 int used; /* actually used size in words. */
1822 int bits; /* flag to record character classes */
1825 #ifdef emacs
1827 /* Make sure that WORK_AREA can hold more N multibyte characters.
1828 This is used only in set_image_of_range and set_image_of_range_1.
1829 It expects WORK_AREA to be a pointer.
1830 If it can't get the space, it returns from the surrounding function. */
1832 #define EXTEND_RANGE_TABLE(work_area, n) \
1833 do { \
1834 if (((work_area).used + (n)) * sizeof (int) > (work_area).allocated) \
1836 extend_range_table_work_area (&work_area); \
1837 if ((work_area).table == 0) \
1838 return (REG_ESPACE); \
1840 } while (0)
1842 #define SET_RANGE_TABLE_WORK_AREA_BIT(work_area, bit) \
1843 (work_area).bits |= (bit)
1845 /* Set a range (RANGE_START, RANGE_END) to WORK_AREA. */
1846 #define SET_RANGE_TABLE_WORK_AREA(work_area, range_start, range_end) \
1847 do { \
1848 EXTEND_RANGE_TABLE ((work_area), 2); \
1849 (work_area).table[(work_area).used++] = (range_start); \
1850 (work_area).table[(work_area).used++] = (range_end); \
1851 } while (0)
1853 #endif /* emacs */
1855 /* Free allocated memory for WORK_AREA. */
1856 #define FREE_RANGE_TABLE_WORK_AREA(work_area) \
1857 do { \
1858 if ((work_area).table) \
1859 free ((work_area).table); \
1860 } while (0)
1862 #define CLEAR_RANGE_TABLE_WORK_USED(work_area) ((work_area).used = 0, (work_area).bits = 0)
1863 #define RANGE_TABLE_WORK_USED(work_area) ((work_area).used)
1864 #define RANGE_TABLE_WORK_BITS(work_area) ((work_area).bits)
1865 #define RANGE_TABLE_WORK_ELT(work_area, i) ((work_area).table[i])
1867 /* Bits used to implement the multibyte-part of the various character classes
1868 such as [:alnum:] in a charset's range table. The code currently assumes
1869 that only the low 16 bits are used. */
1870 #define BIT_WORD 0x1
1871 #define BIT_LOWER 0x2
1872 #define BIT_PUNCT 0x4
1873 #define BIT_SPACE 0x8
1874 #define BIT_UPPER 0x10
1875 #define BIT_MULTIBYTE 0x20
1876 #define BIT_ALPHA 0x40
1877 #define BIT_ALNUM 0x80
1878 #define BIT_GRAPH 0x100
1879 #define BIT_PRINT 0x200
1882 /* Set the bit for character C in a list. */
1883 #define SET_LIST_BIT(c) (b[((c)) / BYTEWIDTH] |= 1 << ((c) % BYTEWIDTH))
1886 #ifdef emacs
1888 /* Store characters in the range FROM to TO in the bitmap at B (for
1889 ASCII and unibyte characters) and WORK_AREA (for multibyte
1890 characters) while translating them and paying attention to the
1891 continuity of translated characters.
1893 Implementation note: It is better to implement these fairly big
1894 macros by a function, but it's not that easy because macros called
1895 in this macro assume various local variables already declared. */
1897 /* Both FROM and TO are ASCII characters. */
1899 #define SETUP_ASCII_RANGE(work_area, FROM, TO) \
1900 do { \
1901 int C0, C1; \
1903 for (C0 = (FROM); C0 <= (TO); C0++) \
1905 C1 = TRANSLATE (C0); \
1906 if (! ASCII_CHAR_P (C1)) \
1908 SET_RANGE_TABLE_WORK_AREA ((work_area), C1, C1); \
1909 if ((C1 = RE_CHAR_TO_UNIBYTE (C1)) < 0) \
1910 C1 = C0; \
1912 SET_LIST_BIT (C1); \
1914 } while (0)
1917 /* Both FROM and TO are unibyte characters (0x80..0xFF). */
1919 #define SETUP_UNIBYTE_RANGE(work_area, FROM, TO) \
1920 do { \
1921 int C0, C1, C2, I; \
1922 int USED = RANGE_TABLE_WORK_USED (work_area); \
1924 for (C0 = (FROM); C0 <= (TO); C0++) \
1926 C1 = RE_CHAR_TO_MULTIBYTE (C0); \
1927 if (CHAR_BYTE8_P (C1)) \
1928 SET_LIST_BIT (C0); \
1929 else \
1931 C2 = TRANSLATE (C1); \
1932 if (C2 == C1 \
1933 || (C1 = RE_CHAR_TO_UNIBYTE (C2)) < 0) \
1934 C1 = C0; \
1935 SET_LIST_BIT (C1); \
1936 for (I = RANGE_TABLE_WORK_USED (work_area) - 2; I >= USED; I -= 2) \
1938 int from = RANGE_TABLE_WORK_ELT (work_area, I); \
1939 int to = RANGE_TABLE_WORK_ELT (work_area, I + 1); \
1941 if (C2 >= from - 1 && C2 <= to + 1) \
1943 if (C2 == from - 1) \
1944 RANGE_TABLE_WORK_ELT (work_area, I)--; \
1945 else if (C2 == to + 1) \
1946 RANGE_TABLE_WORK_ELT (work_area, I + 1)++; \
1947 break; \
1950 if (I < USED) \
1951 SET_RANGE_TABLE_WORK_AREA ((work_area), C2, C2); \
1954 } while (0)
1957 /* Both FROM and TO are multibyte characters. */
1959 #define SETUP_MULTIBYTE_RANGE(work_area, FROM, TO) \
1960 do { \
1961 int C0, C1, C2, I, USED = RANGE_TABLE_WORK_USED (work_area); \
1963 SET_RANGE_TABLE_WORK_AREA ((work_area), (FROM), (TO)); \
1964 for (C0 = (FROM); C0 <= (TO); C0++) \
1966 C1 = TRANSLATE (C0); \
1967 if ((C2 = RE_CHAR_TO_UNIBYTE (C1)) >= 0 \
1968 || (C1 != C0 && (C2 = RE_CHAR_TO_UNIBYTE (C0)) >= 0)) \
1969 SET_LIST_BIT (C2); \
1970 if (C1 >= (FROM) && C1 <= (TO)) \
1971 continue; \
1972 for (I = RANGE_TABLE_WORK_USED (work_area) - 2; I >= USED; I -= 2) \
1974 int from = RANGE_TABLE_WORK_ELT (work_area, I); \
1975 int to = RANGE_TABLE_WORK_ELT (work_area, I + 1); \
1977 if (C1 >= from - 1 && C1 <= to + 1) \
1979 if (C1 == from - 1) \
1980 RANGE_TABLE_WORK_ELT (work_area, I)--; \
1981 else if (C1 == to + 1) \
1982 RANGE_TABLE_WORK_ELT (work_area, I + 1)++; \
1983 break; \
1986 if (I < USED) \
1987 SET_RANGE_TABLE_WORK_AREA ((work_area), C1, C1); \
1989 } while (0)
1991 #endif /* emacs */
1993 /* Get the next unsigned number in the uncompiled pattern. */
1994 #define GET_INTERVAL_COUNT(num) \
1995 do { \
1996 if (p == pend) \
1997 FREE_STACK_RETURN (REG_EBRACE); \
1998 else \
2000 PATFETCH (c); \
2001 while ('0' <= c && c <= '9') \
2003 if (num < 0) \
2004 num = 0; \
2005 if (RE_DUP_MAX / 10 - (RE_DUP_MAX % 10 < c - '0') < num) \
2006 FREE_STACK_RETURN (REG_BADBR); \
2007 num = num * 10 + c - '0'; \
2008 if (p == pend) \
2009 FREE_STACK_RETURN (REG_EBRACE); \
2010 PATFETCH (c); \
2013 } while (0)
2015 #if ! WIDE_CHAR_SUPPORT
2017 /* Map a string to the char class it names (if any). */
2018 re_wctype_t
2019 re_wctype (const_re_char *str)
2021 const char *string = (const char *) str;
2022 if (STREQ (string, "alnum")) return RECC_ALNUM;
2023 else if (STREQ (string, "alpha")) return RECC_ALPHA;
2024 else if (STREQ (string, "word")) return RECC_WORD;
2025 else if (STREQ (string, "ascii")) return RECC_ASCII;
2026 else if (STREQ (string, "nonascii")) return RECC_NONASCII;
2027 else if (STREQ (string, "graph")) return RECC_GRAPH;
2028 else if (STREQ (string, "lower")) return RECC_LOWER;
2029 else if (STREQ (string, "print")) return RECC_PRINT;
2030 else if (STREQ (string, "punct")) return RECC_PUNCT;
2031 else if (STREQ (string, "space")) return RECC_SPACE;
2032 else if (STREQ (string, "upper")) return RECC_UPPER;
2033 else if (STREQ (string, "unibyte")) return RECC_UNIBYTE;
2034 else if (STREQ (string, "multibyte")) return RECC_MULTIBYTE;
2035 else if (STREQ (string, "digit")) return RECC_DIGIT;
2036 else if (STREQ (string, "xdigit")) return RECC_XDIGIT;
2037 else if (STREQ (string, "cntrl")) return RECC_CNTRL;
2038 else if (STREQ (string, "blank")) return RECC_BLANK;
2039 else return 0;
2042 /* True if CH is in the char class CC. */
2043 boolean
2044 re_iswctype (int ch, re_wctype_t cc)
2046 switch (cc)
2048 case RECC_ALNUM: return ISALNUM (ch) != 0;
2049 case RECC_ALPHA: return ISALPHA (ch) != 0;
2050 case RECC_BLANK: return ISBLANK (ch) != 0;
2051 case RECC_CNTRL: return ISCNTRL (ch) != 0;
2052 case RECC_DIGIT: return ISDIGIT (ch) != 0;
2053 case RECC_GRAPH: return ISGRAPH (ch) != 0;
2054 case RECC_LOWER: return ISLOWER (ch) != 0;
2055 case RECC_PRINT: return ISPRINT (ch) != 0;
2056 case RECC_PUNCT: return ISPUNCT (ch) != 0;
2057 case RECC_SPACE: return ISSPACE (ch) != 0;
2058 case RECC_UPPER: return ISUPPER (ch) != 0;
2059 case RECC_XDIGIT: return ISXDIGIT (ch) != 0;
2060 case RECC_ASCII: return IS_REAL_ASCII (ch) != 0;
2061 case RECC_NONASCII: return !IS_REAL_ASCII (ch);
2062 case RECC_UNIBYTE: return ISUNIBYTE (ch) != 0;
2063 case RECC_MULTIBYTE: return !ISUNIBYTE (ch);
2064 case RECC_WORD: return ISWORD (ch) != 0;
2065 case RECC_ERROR: return false;
2066 default:
2067 abort ();
2071 /* Return a bit-pattern to use in the range-table bits to match multibyte
2072 chars of class CC. */
2073 static int
2074 re_wctype_to_bit (re_wctype_t cc)
2076 switch (cc)
2078 case RECC_NONASCII:
2079 case RECC_MULTIBYTE: return BIT_MULTIBYTE;
2080 case RECC_ALPHA: return BIT_ALPHA;
2081 case RECC_ALNUM: return BIT_ALNUM;
2082 case RECC_WORD: return BIT_WORD;
2083 case RECC_LOWER: return BIT_LOWER;
2084 case RECC_UPPER: return BIT_UPPER;
2085 case RECC_PUNCT: return BIT_PUNCT;
2086 case RECC_SPACE: return BIT_SPACE;
2087 case RECC_GRAPH: return BIT_GRAPH;
2088 case RECC_PRINT: return BIT_PRINT;
2089 case RECC_ASCII: case RECC_DIGIT: case RECC_XDIGIT: case RECC_CNTRL:
2090 case RECC_BLANK: case RECC_UNIBYTE: case RECC_ERROR: return 0;
2091 default:
2092 abort ();
2095 #endif
2097 /* Filling in the work area of a range. */
2099 /* Actually extend the space in WORK_AREA. */
2101 static void
2102 extend_range_table_work_area (struct range_table_work_area *work_area)
2104 work_area->allocated += 16 * sizeof (int);
2105 work_area->table = realloc (work_area->table, work_area->allocated);
2108 #if 0
2109 #ifdef emacs
2111 /* Carefully find the ranges of codes that are equivalent
2112 under case conversion to the range start..end when passed through
2113 TRANSLATE. Handle the case where non-letters can come in between
2114 two upper-case letters (which happens in Latin-1).
2115 Also handle the case of groups of more than 2 case-equivalent chars.
2117 The basic method is to look at consecutive characters and see
2118 if they can form a run that can be handled as one.
2120 Returns -1 if successful, REG_ESPACE if ran out of space. */
2122 static int
2123 set_image_of_range_1 (struct range_table_work_area *work_area,
2124 re_wchar_t start, re_wchar_t end,
2125 RE_TRANSLATE_TYPE translate)
2127 /* `one_case' indicates a character, or a run of characters,
2128 each of which is an isolate (no case-equivalents).
2129 This includes all ASCII non-letters.
2131 `two_case' indicates a character, or a run of characters,
2132 each of which has two case-equivalent forms.
2133 This includes all ASCII letters.
2135 `strange' indicates a character that has more than one
2136 case-equivalent. */
2138 enum case_type {one_case, two_case, strange};
2140 /* Describe the run that is in progress,
2141 which the next character can try to extend.
2142 If run_type is strange, that means there really is no run.
2143 If run_type is one_case, then run_start...run_end is the run.
2144 If run_type is two_case, then the run is run_start...run_end,
2145 and the case-equivalents end at run_eqv_end. */
2147 enum case_type run_type = strange;
2148 int run_start, run_end, run_eqv_end;
2150 Lisp_Object eqv_table;
2152 if (!RE_TRANSLATE_P (translate))
2154 EXTEND_RANGE_TABLE (work_area, 2);
2155 work_area->table[work_area->used++] = (start);
2156 work_area->table[work_area->used++] = (end);
2157 return -1;
2160 eqv_table = XCHAR_TABLE (translate)->extras[2];
2162 for (; start <= end; start++)
2164 enum case_type this_type;
2165 int eqv = RE_TRANSLATE (eqv_table, start);
2166 int minchar, maxchar;
2168 /* Classify this character */
2169 if (eqv == start)
2170 this_type = one_case;
2171 else if (RE_TRANSLATE (eqv_table, eqv) == start)
2172 this_type = two_case;
2173 else
2174 this_type = strange;
2176 if (start < eqv)
2177 minchar = start, maxchar = eqv;
2178 else
2179 minchar = eqv, maxchar = start;
2181 /* Can this character extend the run in progress? */
2182 if (this_type == strange || this_type != run_type
2183 || !(minchar == run_end + 1
2184 && (run_type == two_case
2185 ? maxchar == run_eqv_end + 1 : 1)))
2187 /* No, end the run.
2188 Record each of its equivalent ranges. */
2189 if (run_type == one_case)
2191 EXTEND_RANGE_TABLE (work_area, 2);
2192 work_area->table[work_area->used++] = run_start;
2193 work_area->table[work_area->used++] = run_end;
2195 else if (run_type == two_case)
2197 EXTEND_RANGE_TABLE (work_area, 4);
2198 work_area->table[work_area->used++] = run_start;
2199 work_area->table[work_area->used++] = run_end;
2200 work_area->table[work_area->used++]
2201 = RE_TRANSLATE (eqv_table, run_start);
2202 work_area->table[work_area->used++]
2203 = RE_TRANSLATE (eqv_table, run_end);
2205 run_type = strange;
2208 if (this_type == strange)
2210 /* For a strange character, add each of its equivalents, one
2211 by one. Don't start a range. */
2214 EXTEND_RANGE_TABLE (work_area, 2);
2215 work_area->table[work_area->used++] = eqv;
2216 work_area->table[work_area->used++] = eqv;
2217 eqv = RE_TRANSLATE (eqv_table, eqv);
2219 while (eqv != start);
2222 /* Add this char to the run, or start a new run. */
2223 else if (run_type == strange)
2225 /* Initialize a new range. */
2226 run_type = this_type;
2227 run_start = start;
2228 run_end = start;
2229 run_eqv_end = RE_TRANSLATE (eqv_table, run_end);
2231 else
2233 /* Extend a running range. */
2234 run_end = minchar;
2235 run_eqv_end = RE_TRANSLATE (eqv_table, run_end);
2239 /* If a run is still in progress at the end, finish it now
2240 by recording its equivalent ranges. */
2241 if (run_type == one_case)
2243 EXTEND_RANGE_TABLE (work_area, 2);
2244 work_area->table[work_area->used++] = run_start;
2245 work_area->table[work_area->used++] = run_end;
2247 else if (run_type == two_case)
2249 EXTEND_RANGE_TABLE (work_area, 4);
2250 work_area->table[work_area->used++] = run_start;
2251 work_area->table[work_area->used++] = run_end;
2252 work_area->table[work_area->used++]
2253 = RE_TRANSLATE (eqv_table, run_start);
2254 work_area->table[work_area->used++]
2255 = RE_TRANSLATE (eqv_table, run_end);
2258 return -1;
2261 #endif /* emacs */
2263 /* Record the image of the range start..end when passed through
2264 TRANSLATE. This is not necessarily TRANSLATE(start)..TRANSLATE(end)
2265 and is not even necessarily contiguous.
2266 Normally we approximate it with the smallest contiguous range that contains
2267 all the chars we need. However, for Latin-1 we go to extra effort
2268 to do a better job.
2270 This function is not called for ASCII ranges.
2272 Returns -1 if successful, REG_ESPACE if ran out of space. */
2274 static int
2275 set_image_of_range (struct range_table_work_area *work_area,
2276 re_wchar_t start, re_wchar_t end,
2277 RE_TRANSLATE_TYPE translate)
2279 re_wchar_t cmin, cmax;
2281 #ifdef emacs
2282 /* For Latin-1 ranges, use set_image_of_range_1
2283 to get proper handling of ranges that include letters and nonletters.
2284 For a range that includes the whole of Latin-1, this is not necessary.
2285 For other character sets, we don't bother to get this right. */
2286 if (RE_TRANSLATE_P (translate) && start < 04400
2287 && !(start < 04200 && end >= 04377))
2289 int newend;
2290 int tem;
2291 newend = end;
2292 if (newend > 04377)
2293 newend = 04377;
2294 tem = set_image_of_range_1 (work_area, start, newend, translate);
2295 if (tem > 0)
2296 return tem;
2298 start = 04400;
2299 if (end < 04400)
2300 return -1;
2302 #endif
2304 EXTEND_RANGE_TABLE (work_area, 2);
2305 work_area->table[work_area->used++] = (start);
2306 work_area->table[work_area->used++] = (end);
2308 cmin = -1, cmax = -1;
2310 if (RE_TRANSLATE_P (translate))
2312 int ch;
2314 for (ch = start; ch <= end; ch++)
2316 re_wchar_t c = TRANSLATE (ch);
2317 if (! (start <= c && c <= end))
2319 if (cmin == -1)
2320 cmin = c, cmax = c;
2321 else
2323 cmin = min (cmin, c);
2324 cmax = max (cmax, c);
2329 if (cmin != -1)
2331 EXTEND_RANGE_TABLE (work_area, 2);
2332 work_area->table[work_area->used++] = (cmin);
2333 work_area->table[work_area->used++] = (cmax);
2337 return -1;
2339 #endif /* 0 */
2341 #ifndef MATCH_MAY_ALLOCATE
2343 /* If we cannot allocate large objects within re_match_2_internal,
2344 we make the fail stack and register vectors global.
2345 The fail stack, we grow to the maximum size when a regexp
2346 is compiled.
2347 The register vectors, we adjust in size each time we
2348 compile a regexp, according to the number of registers it needs. */
2350 static fail_stack_type fail_stack;
2352 /* Size with which the following vectors are currently allocated.
2353 That is so we can make them bigger as needed,
2354 but never make them smaller. */
2355 static int regs_allocated_size;
2357 static re_char ** regstart, ** regend;
2358 static re_char **best_regstart, **best_regend;
2360 /* Make the register vectors big enough for NUM_REGS registers,
2361 but don't make them smaller. */
2363 static
2364 regex_grow_registers (int num_regs)
2366 if (num_regs > regs_allocated_size)
2368 RETALLOC_IF (regstart, num_regs, re_char *);
2369 RETALLOC_IF (regend, num_regs, re_char *);
2370 RETALLOC_IF (best_regstart, num_regs, re_char *);
2371 RETALLOC_IF (best_regend, num_regs, re_char *);
2373 regs_allocated_size = num_regs;
2377 #endif /* not MATCH_MAY_ALLOCATE */
2379 static boolean group_in_compile_stack (compile_stack_type compile_stack,
2380 regnum_t regnum);
2382 /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
2383 Returns one of error codes defined in `regex.h', or zero for success.
2385 Assumes the `allocated' (and perhaps `buffer') and `translate'
2386 fields are set in BUFP on entry.
2388 If it succeeds, results are put in BUFP (if it returns an error, the
2389 contents of BUFP are undefined):
2390 `buffer' is the compiled pattern;
2391 `syntax' is set to SYNTAX;
2392 `used' is set to the length of the compiled pattern;
2393 `fastmap_accurate' is zero;
2394 `re_nsub' is the number of subexpressions in PATTERN;
2395 `not_bol' and `not_eol' are zero;
2397 The `fastmap' field is neither examined nor set. */
2399 /* Insert the `jump' from the end of last alternative to "here".
2400 The space for the jump has already been allocated. */
2401 #define FIXUP_ALT_JUMP() \
2402 do { \
2403 if (fixup_alt_jump) \
2404 STORE_JUMP (jump, fixup_alt_jump, b); \
2405 } while (0)
2408 /* Return, freeing storage we allocated. */
2409 #define FREE_STACK_RETURN(value) \
2410 do { \
2411 FREE_RANGE_TABLE_WORK_AREA (range_table_work); \
2412 free (compile_stack.stack); \
2413 return value; \
2414 } while (0)
2416 static reg_errcode_t
2417 regex_compile (const_re_char *pattern, size_t size, reg_syntax_t syntax,
2418 struct re_pattern_buffer *bufp)
2420 /* We fetch characters from PATTERN here. */
2421 register re_wchar_t c, c1;
2423 /* Points to the end of the buffer, where we should append. */
2424 register unsigned char *b;
2426 /* Keeps track of unclosed groups. */
2427 compile_stack_type compile_stack;
2429 /* Points to the current (ending) position in the pattern. */
2430 #ifdef AIX
2431 /* `const' makes AIX compiler fail. */
2432 unsigned char *p = pattern;
2433 #else
2434 re_char *p = pattern;
2435 #endif
2436 re_char *pend = pattern + size;
2438 /* How to translate the characters in the pattern. */
2439 RE_TRANSLATE_TYPE translate = bufp->translate;
2441 /* Address of the count-byte of the most recently inserted `exactn'
2442 command. This makes it possible to tell if a new exact-match
2443 character can be added to that command or if the character requires
2444 a new `exactn' command. */
2445 unsigned char *pending_exact = 0;
2447 /* Address of start of the most recently finished expression.
2448 This tells, e.g., postfix * where to find the start of its
2449 operand. Reset at the beginning of groups and alternatives. */
2450 unsigned char *laststart = 0;
2452 /* Address of beginning of regexp, or inside of last group. */
2453 unsigned char *begalt;
2455 /* Place in the uncompiled pattern (i.e., the {) to
2456 which to go back if the interval is invalid. */
2457 re_char *beg_interval;
2459 /* Address of the place where a forward jump should go to the end of
2460 the containing expression. Each alternative of an `or' -- except the
2461 last -- ends with a forward jump of this sort. */
2462 unsigned char *fixup_alt_jump = 0;
2464 /* Work area for range table of charset. */
2465 struct range_table_work_area range_table_work;
2467 /* If the object matched can contain multibyte characters. */
2468 const boolean multibyte = RE_MULTIBYTE_P (bufp);
2470 /* Nonzero if we have pushed down into a subpattern. */
2471 int in_subpattern = 0;
2473 /* These hold the values of p, pattern, and pend from the main
2474 pattern when we have pushed into a subpattern. */
2475 re_char *main_p IF_LINT (= NULL);
2476 re_char *main_pattern IF_LINT (= NULL);
2477 re_char *main_pend IF_LINT (= NULL);
2479 #ifdef DEBUG
2480 debug++;
2481 DEBUG_PRINT ("\nCompiling pattern: ");
2482 if (debug > 0)
2484 unsigned debug_count;
2486 for (debug_count = 0; debug_count < size; debug_count++)
2487 putchar (pattern[debug_count]);
2488 putchar ('\n');
2490 #endif /* DEBUG */
2492 /* Initialize the compile stack. */
2493 compile_stack.stack = TALLOC (INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
2494 if (compile_stack.stack == NULL)
2495 return REG_ESPACE;
2497 compile_stack.size = INIT_COMPILE_STACK_SIZE;
2498 compile_stack.avail = 0;
2500 range_table_work.table = 0;
2501 range_table_work.allocated = 0;
2503 /* Initialize the pattern buffer. */
2504 bufp->syntax = syntax;
2505 bufp->fastmap_accurate = 0;
2506 bufp->not_bol = bufp->not_eol = 0;
2507 bufp->used_syntax = 0;
2509 /* Set `used' to zero, so that if we return an error, the pattern
2510 printer (for debugging) will think there's no pattern. We reset it
2511 at the end. */
2512 bufp->used = 0;
2514 /* Always count groups, whether or not bufp->no_sub is set. */
2515 bufp->re_nsub = 0;
2517 #if !defined emacs && !defined SYNTAX_TABLE
2518 /* Initialize the syntax table. */
2519 init_syntax_once ();
2520 #endif
2522 if (bufp->allocated == 0)
2524 if (bufp->buffer)
2525 { /* If zero allocated, but buffer is non-null, try to realloc
2526 enough space. This loses if buffer's address is bogus, but
2527 that is the user's responsibility. */
2528 RETALLOC (bufp->buffer, INIT_BUF_SIZE, unsigned char);
2530 else
2531 { /* Caller did not allocate a buffer. Do it for them. */
2532 bufp->buffer = TALLOC (INIT_BUF_SIZE, unsigned char);
2534 if (!bufp->buffer) FREE_STACK_RETURN (REG_ESPACE);
2536 bufp->allocated = INIT_BUF_SIZE;
2539 begalt = b = bufp->buffer;
2541 /* Loop through the uncompiled pattern until we're at the end. */
2542 while (1)
2544 if (p == pend)
2546 /* If this is the end of an included regexp,
2547 pop back to the main regexp and try again. */
2548 if (in_subpattern)
2550 in_subpattern = 0;
2551 pattern = main_pattern;
2552 p = main_p;
2553 pend = main_pend;
2554 continue;
2556 /* If this is the end of the main regexp, we are done. */
2557 break;
2560 PATFETCH (c);
2562 switch (c)
2564 case ' ':
2566 re_char *p1 = p;
2568 /* If there's no special whitespace regexp, treat
2569 spaces normally. And don't try to do this recursively. */
2570 if (!whitespace_regexp || in_subpattern)
2571 goto normal_char;
2573 /* Peek past following spaces. */
2574 while (p1 != pend)
2576 if (*p1 != ' ')
2577 break;
2578 p1++;
2580 /* If the spaces are followed by a repetition op,
2581 treat them normally. */
2582 if (p1 != pend
2583 && (*p1 == '*' || *p1 == '+' || *p1 == '?'
2584 || (*p1 == '\\' && p1 + 1 != pend && p1[1] == '{')))
2585 goto normal_char;
2587 /* Replace the spaces with the whitespace regexp. */
2588 in_subpattern = 1;
2589 main_p = p1;
2590 main_pend = pend;
2591 main_pattern = pattern;
2592 p = pattern = whitespace_regexp;
2593 pend = p + strlen ((const char *) p);
2594 break;
2597 case '^':
2599 if ( /* If at start of pattern, it's an operator. */
2600 p == pattern + 1
2601 /* If context independent, it's an operator. */
2602 || syntax & RE_CONTEXT_INDEP_ANCHORS
2603 /* Otherwise, depends on what's come before. */
2604 || at_begline_loc_p (pattern, p, syntax))
2605 BUF_PUSH ((syntax & RE_NO_NEWLINE_ANCHOR) ? begbuf : begline);
2606 else
2607 goto normal_char;
2609 break;
2612 case '$':
2614 if ( /* If at end of pattern, it's an operator. */
2615 p == pend
2616 /* If context independent, it's an operator. */
2617 || syntax & RE_CONTEXT_INDEP_ANCHORS
2618 /* Otherwise, depends on what's next. */
2619 || at_endline_loc_p (p, pend, syntax))
2620 BUF_PUSH ((syntax & RE_NO_NEWLINE_ANCHOR) ? endbuf : endline);
2621 else
2622 goto normal_char;
2624 break;
2627 case '+':
2628 case '?':
2629 if ((syntax & RE_BK_PLUS_QM)
2630 || (syntax & RE_LIMITED_OPS))
2631 goto normal_char;
2632 handle_plus:
2633 case '*':
2634 /* If there is no previous pattern... */
2635 if (!laststart)
2637 if (syntax & RE_CONTEXT_INVALID_OPS)
2638 FREE_STACK_RETURN (REG_BADRPT);
2639 else if (!(syntax & RE_CONTEXT_INDEP_OPS))
2640 goto normal_char;
2644 /* 1 means zero (many) matches is allowed. */
2645 boolean zero_times_ok = 0, many_times_ok = 0;
2646 boolean greedy = 1;
2648 /* If there is a sequence of repetition chars, collapse it
2649 down to just one (the right one). We can't combine
2650 interval operators with these because of, e.g., `a{2}*',
2651 which should only match an even number of `a's. */
2653 for (;;)
2655 if ((syntax & RE_FRUGAL)
2656 && c == '?' && (zero_times_ok || many_times_ok))
2657 greedy = 0;
2658 else
2660 zero_times_ok |= c != '+';
2661 many_times_ok |= c != '?';
2664 if (p == pend)
2665 break;
2666 else if (*p == '*'
2667 || (!(syntax & RE_BK_PLUS_QM)
2668 && (*p == '+' || *p == '?')))
2670 else if (syntax & RE_BK_PLUS_QM && *p == '\\')
2672 if (p+1 == pend)
2673 FREE_STACK_RETURN (REG_EESCAPE);
2674 if (p[1] == '+' || p[1] == '?')
2675 PATFETCH (c); /* Gobble up the backslash. */
2676 else
2677 break;
2679 else
2680 break;
2681 /* If we get here, we found another repeat character. */
2682 PATFETCH (c);
2685 /* Star, etc. applied to an empty pattern is equivalent
2686 to an empty pattern. */
2687 if (!laststart || laststart == b)
2688 break;
2690 /* Now we know whether or not zero matches is allowed
2691 and also whether or not two or more matches is allowed. */
2692 if (greedy)
2694 if (many_times_ok)
2696 boolean simple = skip_one_char (laststart) == b;
2697 size_t startoffset = 0;
2698 re_opcode_t ofj =
2699 /* Check if the loop can match the empty string. */
2700 (simple || !analyze_first (laststart, b, NULL, 0))
2701 ? on_failure_jump : on_failure_jump_loop;
2702 assert (skip_one_char (laststart) <= b);
2704 if (!zero_times_ok && simple)
2705 { /* Since simple * loops can be made faster by using
2706 on_failure_keep_string_jump, we turn simple P+
2707 into PP* if P is simple. */
2708 unsigned char *p1, *p2;
2709 startoffset = b - laststart;
2710 GET_BUFFER_SPACE (startoffset);
2711 p1 = b; p2 = laststart;
2712 while (p2 < p1)
2713 *b++ = *p2++;
2714 zero_times_ok = 1;
2717 GET_BUFFER_SPACE (6);
2718 if (!zero_times_ok)
2719 /* A + loop. */
2720 STORE_JUMP (ofj, b, b + 6);
2721 else
2722 /* Simple * loops can use on_failure_keep_string_jump
2723 depending on what follows. But since we don't know
2724 that yet, we leave the decision up to
2725 on_failure_jump_smart. */
2726 INSERT_JUMP (simple ? on_failure_jump_smart : ofj,
2727 laststart + startoffset, b + 6);
2728 b += 3;
2729 STORE_JUMP (jump, b, laststart + startoffset);
2730 b += 3;
2732 else
2734 /* A simple ? pattern. */
2735 assert (zero_times_ok);
2736 GET_BUFFER_SPACE (3);
2737 INSERT_JUMP (on_failure_jump, laststart, b + 3);
2738 b += 3;
2741 else /* not greedy */
2742 { /* I wish the greedy and non-greedy cases could be merged. */
2744 GET_BUFFER_SPACE (7); /* We might use less. */
2745 if (many_times_ok)
2747 boolean emptyp = analyze_first (laststart, b, NULL, 0);
2749 /* The non-greedy multiple match looks like
2750 a repeat..until: we only need a conditional jump
2751 at the end of the loop. */
2752 if (emptyp) BUF_PUSH (no_op);
2753 STORE_JUMP (emptyp ? on_failure_jump_nastyloop
2754 : on_failure_jump, b, laststart);
2755 b += 3;
2756 if (zero_times_ok)
2758 /* The repeat...until naturally matches one or more.
2759 To also match zero times, we need to first jump to
2760 the end of the loop (its conditional jump). */
2761 INSERT_JUMP (jump, laststart, b);
2762 b += 3;
2765 else
2767 /* non-greedy a?? */
2768 INSERT_JUMP (jump, laststart, b + 3);
2769 b += 3;
2770 INSERT_JUMP (on_failure_jump, laststart, laststart + 6);
2771 b += 3;
2775 pending_exact = 0;
2776 break;
2779 case '.':
2780 laststart = b;
2781 BUF_PUSH (anychar);
2782 break;
2785 case '[':
2787 re_char *p1;
2789 CLEAR_RANGE_TABLE_WORK_USED (range_table_work);
2791 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2793 /* Ensure that we have enough space to push a charset: the
2794 opcode, the length count, and the bitset; 34 bytes in all. */
2795 GET_BUFFER_SPACE (34);
2797 laststart = b;
2799 /* We test `*p == '^' twice, instead of using an if
2800 statement, so we only need one BUF_PUSH. */
2801 BUF_PUSH (*p == '^' ? charset_not : charset);
2802 if (*p == '^')
2803 p++;
2805 /* Remember the first position in the bracket expression. */
2806 p1 = p;
2808 /* Push the number of bytes in the bitmap. */
2809 BUF_PUSH ((1 << BYTEWIDTH) / BYTEWIDTH);
2811 /* Clear the whole map. */
2812 memset (b, 0, (1 << BYTEWIDTH) / BYTEWIDTH);
2814 /* charset_not matches newline according to a syntax bit. */
2815 if ((re_opcode_t) b[-2] == charset_not
2816 && (syntax & RE_HAT_LISTS_NOT_NEWLINE))
2817 SET_LIST_BIT ('\n');
2819 /* Read in characters and ranges, setting map bits. */
2820 for (;;)
2822 boolean escaped_char = false;
2823 const unsigned char *p2 = p;
2824 re_wchar_t ch;
2826 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2828 /* Don't translate yet. The range TRANSLATE(X..Y) cannot
2829 always be determined from TRANSLATE(X) and TRANSLATE(Y)
2830 So the translation is done later in a loop. Example:
2831 (let ((case-fold-search t)) (string-match "[A-_]" "A")) */
2832 PATFETCH (c);
2834 /* \ might escape characters inside [...] and [^...]. */
2835 if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\')
2837 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2839 PATFETCH (c);
2840 escaped_char = true;
2842 else
2844 /* Could be the end of the bracket expression. If it's
2845 not (i.e., when the bracket expression is `[]' so
2846 far), the ']' character bit gets set way below. */
2847 if (c == ']' && p2 != p1)
2848 break;
2851 /* See if we're at the beginning of a possible character
2852 class. */
2854 if (!escaped_char &&
2855 syntax & RE_CHAR_CLASSES && c == '[' && *p == ':')
2857 /* Leave room for the null. */
2858 unsigned char str[CHAR_CLASS_MAX_LENGTH + 1];
2859 const unsigned char *class_beg;
2861 PATFETCH (c);
2862 c1 = 0;
2863 class_beg = p;
2865 /* If pattern is `[[:'. */
2866 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2868 for (;;)
2870 PATFETCH (c);
2871 if ((c == ':' && *p == ']') || p == pend)
2872 break;
2873 if (c1 < CHAR_CLASS_MAX_LENGTH)
2874 str[c1++] = c;
2875 else
2876 /* This is in any case an invalid class name. */
2877 str[0] = '\0';
2879 str[c1] = '\0';
2881 /* If isn't a word bracketed by `[:' and `:]':
2882 undo the ending character, the letters, and
2883 leave the leading `:' and `[' (but set bits for
2884 them). */
2885 if (c == ':' && *p == ']')
2887 re_wctype_t cc = re_wctype (str);
2889 if (cc == 0)
2890 FREE_STACK_RETURN (REG_ECTYPE);
2892 /* Throw away the ] at the end of the character
2893 class. */
2894 PATFETCH (c);
2896 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2898 #ifndef emacs
2899 for (ch = 0; ch < (1 << BYTEWIDTH); ++ch)
2900 if (re_iswctype (btowc (ch), cc))
2902 c = TRANSLATE (ch);
2903 if (c < (1 << BYTEWIDTH))
2904 SET_LIST_BIT (c);
2906 #else /* emacs */
2907 /* Most character classes in a multibyte match
2908 just set a flag. Exceptions are is_blank,
2909 is_digit, is_cntrl, and is_xdigit, since
2910 they can only match ASCII characters. We
2911 don't need to handle them for multibyte.
2912 They are distinguished by a negative wctype. */
2914 /* Setup the gl_state object to its buffer-defined
2915 value. This hardcodes the buffer-global
2916 syntax-table for ASCII chars, while the other chars
2917 will obey syntax-table properties. It's not ideal,
2918 but it's the way it's been done until now. */
2919 SETUP_BUFFER_SYNTAX_TABLE ();
2921 for (ch = 0; ch < 256; ++ch)
2923 c = RE_CHAR_TO_MULTIBYTE (ch);
2924 if (! CHAR_BYTE8_P (c)
2925 && re_iswctype (c, cc))
2927 SET_LIST_BIT (ch);
2928 c1 = TRANSLATE (c);
2929 if (c1 == c)
2930 continue;
2931 if (ASCII_CHAR_P (c1))
2932 SET_LIST_BIT (c1);
2933 else if ((c1 = RE_CHAR_TO_UNIBYTE (c1)) >= 0)
2934 SET_LIST_BIT (c1);
2937 SET_RANGE_TABLE_WORK_AREA_BIT
2938 (range_table_work, re_wctype_to_bit (cc));
2939 #endif /* emacs */
2940 /* In most cases the matching rule for char classes
2941 only uses the syntax table for multibyte chars,
2942 so that the content of the syntax-table is not
2943 hardcoded in the range_table. SPACE and WORD are
2944 the two exceptions. */
2945 if ((1 << cc) & ((1 << RECC_SPACE) | (1 << RECC_WORD)))
2946 bufp->used_syntax = 1;
2948 /* Repeat the loop. */
2949 continue;
2951 else
2953 /* Go back to right after the "[:". */
2954 p = class_beg;
2955 SET_LIST_BIT ('[');
2957 /* Because the `:' may start the range, we
2958 can't simply set bit and repeat the loop.
2959 Instead, just set it to C and handle below. */
2960 c = ':';
2964 if (p < pend && p[0] == '-' && p[1] != ']')
2967 /* Discard the `-'. */
2968 PATFETCH (c1);
2970 /* Fetch the character which ends the range. */
2971 PATFETCH (c1);
2972 #ifdef emacs
2973 if (CHAR_BYTE8_P (c1)
2974 && ! ASCII_CHAR_P (c) && ! CHAR_BYTE8_P (c))
2975 /* Treat the range from a multibyte character to
2976 raw-byte character as empty. */
2977 c = c1 + 1;
2978 #endif /* emacs */
2980 else
2981 /* Range from C to C. */
2982 c1 = c;
2984 if (c > c1)
2986 if (syntax & RE_NO_EMPTY_RANGES)
2987 FREE_STACK_RETURN (REG_ERANGEX);
2988 /* Else, repeat the loop. */
2990 else
2992 #ifndef emacs
2993 /* Set the range into bitmap */
2994 for (; c <= c1; c++)
2996 ch = TRANSLATE (c);
2997 if (ch < (1 << BYTEWIDTH))
2998 SET_LIST_BIT (ch);
3000 #else /* emacs */
3001 if (c < 128)
3003 ch = min (127, c1);
3004 SETUP_ASCII_RANGE (range_table_work, c, ch);
3005 c = ch + 1;
3006 if (CHAR_BYTE8_P (c1))
3007 c = BYTE8_TO_CHAR (128);
3009 if (c <= c1)
3011 if (CHAR_BYTE8_P (c))
3013 c = CHAR_TO_BYTE8 (c);
3014 c1 = CHAR_TO_BYTE8 (c1);
3015 for (; c <= c1; c++)
3016 SET_LIST_BIT (c);
3018 else if (multibyte)
3020 SETUP_MULTIBYTE_RANGE (range_table_work, c, c1);
3022 else
3024 SETUP_UNIBYTE_RANGE (range_table_work, c, c1);
3027 #endif /* emacs */
3031 /* Discard any (non)matching list bytes that are all 0 at the
3032 end of the map. Decrease the map-length byte too. */
3033 while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
3034 b[-1]--;
3035 b += b[-1];
3037 /* Build real range table from work area. */
3038 if (RANGE_TABLE_WORK_USED (range_table_work)
3039 || RANGE_TABLE_WORK_BITS (range_table_work))
3041 int i;
3042 int used = RANGE_TABLE_WORK_USED (range_table_work);
3044 /* Allocate space for COUNT + RANGE_TABLE. Needs two
3045 bytes for flags, two for COUNT, and three bytes for
3046 each character. */
3047 GET_BUFFER_SPACE (4 + used * 3);
3049 /* Indicate the existence of range table. */
3050 laststart[1] |= 0x80;
3052 /* Store the character class flag bits into the range table.
3053 If not in emacs, these flag bits are always 0. */
3054 *b++ = RANGE_TABLE_WORK_BITS (range_table_work) & 0xff;
3055 *b++ = RANGE_TABLE_WORK_BITS (range_table_work) >> 8;
3057 STORE_NUMBER_AND_INCR (b, used / 2);
3058 for (i = 0; i < used; i++)
3059 STORE_CHARACTER_AND_INCR
3060 (b, RANGE_TABLE_WORK_ELT (range_table_work, i));
3063 break;
3066 case '(':
3067 if (syntax & RE_NO_BK_PARENS)
3068 goto handle_open;
3069 else
3070 goto normal_char;
3073 case ')':
3074 if (syntax & RE_NO_BK_PARENS)
3075 goto handle_close;
3076 else
3077 goto normal_char;
3080 case '\n':
3081 if (syntax & RE_NEWLINE_ALT)
3082 goto handle_alt;
3083 else
3084 goto normal_char;
3087 case '|':
3088 if (syntax & RE_NO_BK_VBAR)
3089 goto handle_alt;
3090 else
3091 goto normal_char;
3094 case '{':
3095 if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
3096 goto handle_interval;
3097 else
3098 goto normal_char;
3101 case '\\':
3102 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
3104 /* Do not translate the character after the \, so that we can
3105 distinguish, e.g., \B from \b, even if we normally would
3106 translate, e.g., B to b. */
3107 PATFETCH (c);
3109 switch (c)
3111 case '(':
3112 if (syntax & RE_NO_BK_PARENS)
3113 goto normal_backslash;
3115 handle_open:
3117 int shy = 0;
3118 regnum_t regnum = 0;
3119 if (p+1 < pend)
3121 /* Look for a special (?...) construct */
3122 if ((syntax & RE_SHY_GROUPS) && *p == '?')
3124 PATFETCH (c); /* Gobble up the '?'. */
3125 while (!shy)
3127 PATFETCH (c);
3128 switch (c)
3130 case ':': shy = 1; break;
3131 case '0':
3132 /* An explicitly specified regnum must start
3133 with non-0. */
3134 if (regnum == 0)
3135 FREE_STACK_RETURN (REG_BADPAT);
3136 case '1': case '2': case '3': case '4':
3137 case '5': case '6': case '7': case '8': case '9':
3138 regnum = 10*regnum + (c - '0'); break;
3139 default:
3140 /* Only (?:...) is supported right now. */
3141 FREE_STACK_RETURN (REG_BADPAT);
3147 if (!shy)
3148 regnum = ++bufp->re_nsub;
3149 else if (regnum)
3150 { /* It's actually not shy, but explicitly numbered. */
3151 shy = 0;
3152 if (regnum > bufp->re_nsub)
3153 bufp->re_nsub = regnum;
3154 else if (regnum > bufp->re_nsub
3155 /* Ideally, we'd want to check that the specified
3156 group can't have matched (i.e. all subgroups
3157 using the same regnum are in other branches of
3158 OR patterns), but we don't currently keep track
3159 of enough info to do that easily. */
3160 || group_in_compile_stack (compile_stack, regnum))
3161 FREE_STACK_RETURN (REG_BADPAT);
3163 else
3164 /* It's really shy. */
3165 regnum = - bufp->re_nsub;
3167 if (COMPILE_STACK_FULL)
3169 RETALLOC (compile_stack.stack, compile_stack.size << 1,
3170 compile_stack_elt_t);
3171 if (compile_stack.stack == NULL) return REG_ESPACE;
3173 compile_stack.size <<= 1;
3176 /* These are the values to restore when we hit end of this
3177 group. They are all relative offsets, so that if the
3178 whole pattern moves because of realloc, they will still
3179 be valid. */
3180 COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
3181 COMPILE_STACK_TOP.fixup_alt_jump
3182 = fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
3183 COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
3184 COMPILE_STACK_TOP.regnum = regnum;
3186 /* Do not push a start_memory for groups beyond the last one
3187 we can represent in the compiled pattern. */
3188 if (regnum <= MAX_REGNUM && regnum > 0)
3189 BUF_PUSH_2 (start_memory, regnum);
3191 compile_stack.avail++;
3193 fixup_alt_jump = 0;
3194 laststart = 0;
3195 begalt = b;
3196 /* If we've reached MAX_REGNUM groups, then this open
3197 won't actually generate any code, so we'll have to
3198 clear pending_exact explicitly. */
3199 pending_exact = 0;
3200 break;
3203 case ')':
3204 if (syntax & RE_NO_BK_PARENS) goto normal_backslash;
3206 if (COMPILE_STACK_EMPTY)
3208 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
3209 goto normal_backslash;
3210 else
3211 FREE_STACK_RETURN (REG_ERPAREN);
3214 handle_close:
3215 FIXUP_ALT_JUMP ();
3217 /* See similar code for backslashed left paren above. */
3218 if (COMPILE_STACK_EMPTY)
3220 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
3221 goto normal_char;
3222 else
3223 FREE_STACK_RETURN (REG_ERPAREN);
3226 /* Since we just checked for an empty stack above, this
3227 ``can't happen''. */
3228 assert (compile_stack.avail != 0);
3230 /* We don't just want to restore into `regnum', because
3231 later groups should continue to be numbered higher,
3232 as in `(ab)c(de)' -- the second group is #2. */
3233 regnum_t regnum;
3235 compile_stack.avail--;
3236 begalt = bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
3237 fixup_alt_jump
3238 = COMPILE_STACK_TOP.fixup_alt_jump
3239 ? bufp->buffer + COMPILE_STACK_TOP.fixup_alt_jump - 1
3240 : 0;
3241 laststart = bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
3242 regnum = COMPILE_STACK_TOP.regnum;
3243 /* If we've reached MAX_REGNUM groups, then this open
3244 won't actually generate any code, so we'll have to
3245 clear pending_exact explicitly. */
3246 pending_exact = 0;
3248 /* We're at the end of the group, so now we know how many
3249 groups were inside this one. */
3250 if (regnum <= MAX_REGNUM && regnum > 0)
3251 BUF_PUSH_2 (stop_memory, regnum);
3253 break;
3256 case '|': /* `\|'. */
3257 if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
3258 goto normal_backslash;
3259 handle_alt:
3260 if (syntax & RE_LIMITED_OPS)
3261 goto normal_char;
3263 /* Insert before the previous alternative a jump which
3264 jumps to this alternative if the former fails. */
3265 GET_BUFFER_SPACE (3);
3266 INSERT_JUMP (on_failure_jump, begalt, b + 6);
3267 pending_exact = 0;
3268 b += 3;
3270 /* The alternative before this one has a jump after it
3271 which gets executed if it gets matched. Adjust that
3272 jump so it will jump to this alternative's analogous
3273 jump (put in below, which in turn will jump to the next
3274 (if any) alternative's such jump, etc.). The last such
3275 jump jumps to the correct final destination. A picture:
3276 _____ _____
3277 | | | |
3278 | v | v
3279 a | b | c
3281 If we are at `b', then fixup_alt_jump right now points to a
3282 three-byte space after `a'. We'll put in the jump, set
3283 fixup_alt_jump to right after `b', and leave behind three
3284 bytes which we'll fill in when we get to after `c'. */
3286 FIXUP_ALT_JUMP ();
3288 /* Mark and leave space for a jump after this alternative,
3289 to be filled in later either by next alternative or
3290 when know we're at the end of a series of alternatives. */
3291 fixup_alt_jump = b;
3292 GET_BUFFER_SPACE (3);
3293 b += 3;
3295 laststart = 0;
3296 begalt = b;
3297 break;
3300 case '{':
3301 /* If \{ is a literal. */
3302 if (!(syntax & RE_INTERVALS)
3303 /* If we're at `\{' and it's not the open-interval
3304 operator. */
3305 || (syntax & RE_NO_BK_BRACES))
3306 goto normal_backslash;
3308 handle_interval:
3310 /* If got here, then the syntax allows intervals. */
3312 /* At least (most) this many matches must be made. */
3313 int lower_bound = 0, upper_bound = -1;
3315 beg_interval = p;
3317 GET_INTERVAL_COUNT (lower_bound);
3319 if (c == ',')
3320 GET_INTERVAL_COUNT (upper_bound);
3321 else
3322 /* Interval such as `{1}' => match exactly once. */
3323 upper_bound = lower_bound;
3325 if (lower_bound < 0
3326 || (0 <= upper_bound && upper_bound < lower_bound))
3327 FREE_STACK_RETURN (REG_BADBR);
3329 if (!(syntax & RE_NO_BK_BRACES))
3331 if (c != '\\')
3332 FREE_STACK_RETURN (REG_BADBR);
3333 if (p == pend)
3334 FREE_STACK_RETURN (REG_EESCAPE);
3335 PATFETCH (c);
3338 if (c != '}')
3339 FREE_STACK_RETURN (REG_BADBR);
3341 /* We just parsed a valid interval. */
3343 /* If it's invalid to have no preceding re. */
3344 if (!laststart)
3346 if (syntax & RE_CONTEXT_INVALID_OPS)
3347 FREE_STACK_RETURN (REG_BADRPT);
3348 else if (syntax & RE_CONTEXT_INDEP_OPS)
3349 laststart = b;
3350 else
3351 goto unfetch_interval;
3354 if (upper_bound == 0)
3355 /* If the upper bound is zero, just drop the sub pattern
3356 altogether. */
3357 b = laststart;
3358 else if (lower_bound == 1 && upper_bound == 1)
3359 /* Just match it once: nothing to do here. */
3362 /* Otherwise, we have a nontrivial interval. When
3363 we're all done, the pattern will look like:
3364 set_number_at <jump count> <upper bound>
3365 set_number_at <succeed_n count> <lower bound>
3366 succeed_n <after jump addr> <succeed_n count>
3367 <body of loop>
3368 jump_n <succeed_n addr> <jump count>
3369 (The upper bound and `jump_n' are omitted if
3370 `upper_bound' is 1, though.) */
3371 else
3372 { /* If the upper bound is > 1, we need to insert
3373 more at the end of the loop. */
3374 unsigned int nbytes = (upper_bound < 0 ? 3
3375 : upper_bound > 1 ? 5 : 0);
3376 unsigned int startoffset = 0;
3378 GET_BUFFER_SPACE (20); /* We might use less. */
3380 if (lower_bound == 0)
3382 /* A succeed_n that starts with 0 is really a
3383 a simple on_failure_jump_loop. */
3384 INSERT_JUMP (on_failure_jump_loop, laststart,
3385 b + 3 + nbytes);
3386 b += 3;
3388 else
3390 /* Initialize lower bound of the `succeed_n', even
3391 though it will be set during matching by its
3392 attendant `set_number_at' (inserted next),
3393 because `re_compile_fastmap' needs to know.
3394 Jump to the `jump_n' we might insert below. */
3395 INSERT_JUMP2 (succeed_n, laststart,
3396 b + 5 + nbytes,
3397 lower_bound);
3398 b += 5;
3400 /* Code to initialize the lower bound. Insert
3401 before the `succeed_n'. The `5' is the last two
3402 bytes of this `set_number_at', plus 3 bytes of
3403 the following `succeed_n'. */
3404 insert_op2 (set_number_at, laststart, 5, lower_bound, b);
3405 b += 5;
3406 startoffset += 5;
3409 if (upper_bound < 0)
3411 /* A negative upper bound stands for infinity,
3412 in which case it degenerates to a plain jump. */
3413 STORE_JUMP (jump, b, laststart + startoffset);
3414 b += 3;
3416 else if (upper_bound > 1)
3417 { /* More than one repetition is allowed, so
3418 append a backward jump to the `succeed_n'
3419 that starts this interval.
3421 When we've reached this during matching,
3422 we'll have matched the interval once, so
3423 jump back only `upper_bound - 1' times. */
3424 STORE_JUMP2 (jump_n, b, laststart + startoffset,
3425 upper_bound - 1);
3426 b += 5;
3428 /* The location we want to set is the second
3429 parameter of the `jump_n'; that is `b-2' as
3430 an absolute address. `laststart' will be
3431 the `set_number_at' we're about to insert;
3432 `laststart+3' the number to set, the source
3433 for the relative address. But we are
3434 inserting into the middle of the pattern --
3435 so everything is getting moved up by 5.
3436 Conclusion: (b - 2) - (laststart + 3) + 5,
3437 i.e., b - laststart.
3439 We insert this at the beginning of the loop
3440 so that if we fail during matching, we'll
3441 reinitialize the bounds. */
3442 insert_op2 (set_number_at, laststart, b - laststart,
3443 upper_bound - 1, b);
3444 b += 5;
3447 pending_exact = 0;
3448 beg_interval = NULL;
3450 break;
3452 unfetch_interval:
3453 /* If an invalid interval, match the characters as literals. */
3454 assert (beg_interval);
3455 p = beg_interval;
3456 beg_interval = NULL;
3458 /* normal_char and normal_backslash need `c'. */
3459 c = '{';
3461 if (!(syntax & RE_NO_BK_BRACES))
3463 assert (p > pattern && p[-1] == '\\');
3464 goto normal_backslash;
3466 else
3467 goto normal_char;
3469 #ifdef emacs
3470 /* There is no way to specify the before_dot and after_dot
3471 operators. rms says this is ok. --karl */
3472 case '=':
3473 laststart = b;
3474 BUF_PUSH (at_dot);
3475 break;
3477 case 's':
3478 laststart = b;
3479 PATFETCH (c);
3480 BUF_PUSH_2 (syntaxspec, syntax_spec_code[c]);
3481 break;
3483 case 'S':
3484 laststart = b;
3485 PATFETCH (c);
3486 BUF_PUSH_2 (notsyntaxspec, syntax_spec_code[c]);
3487 break;
3489 case 'c':
3490 laststart = b;
3491 PATFETCH (c);
3492 BUF_PUSH_2 (categoryspec, c);
3493 break;
3495 case 'C':
3496 laststart = b;
3497 PATFETCH (c);
3498 BUF_PUSH_2 (notcategoryspec, c);
3499 break;
3500 #endif /* emacs */
3503 case 'w':
3504 if (syntax & RE_NO_GNU_OPS)
3505 goto normal_char;
3506 laststart = b;
3507 BUF_PUSH_2 (syntaxspec, Sword);
3508 break;
3511 case 'W':
3512 if (syntax & RE_NO_GNU_OPS)
3513 goto normal_char;
3514 laststart = b;
3515 BUF_PUSH_2 (notsyntaxspec, Sword);
3516 break;
3519 case '<':
3520 if (syntax & RE_NO_GNU_OPS)
3521 goto normal_char;
3522 laststart = b;
3523 BUF_PUSH (wordbeg);
3524 break;
3526 case '>':
3527 if (syntax & RE_NO_GNU_OPS)
3528 goto normal_char;
3529 laststart = b;
3530 BUF_PUSH (wordend);
3531 break;
3533 case '_':
3534 if (syntax & RE_NO_GNU_OPS)
3535 goto normal_char;
3536 laststart = b;
3537 PATFETCH (c);
3538 if (c == '<')
3539 BUF_PUSH (symbeg);
3540 else if (c == '>')
3541 BUF_PUSH (symend);
3542 else
3543 FREE_STACK_RETURN (REG_BADPAT);
3544 break;
3546 case 'b':
3547 if (syntax & RE_NO_GNU_OPS)
3548 goto normal_char;
3549 BUF_PUSH (wordbound);
3550 break;
3552 case 'B':
3553 if (syntax & RE_NO_GNU_OPS)
3554 goto normal_char;
3555 BUF_PUSH (notwordbound);
3556 break;
3558 case '`':
3559 if (syntax & RE_NO_GNU_OPS)
3560 goto normal_char;
3561 BUF_PUSH (begbuf);
3562 break;
3564 case '\'':
3565 if (syntax & RE_NO_GNU_OPS)
3566 goto normal_char;
3567 BUF_PUSH (endbuf);
3568 break;
3570 case '1': case '2': case '3': case '4': case '5':
3571 case '6': case '7': case '8': case '9':
3573 regnum_t reg;
3575 if (syntax & RE_NO_BK_REFS)
3576 goto normal_backslash;
3578 reg = c - '0';
3580 if (reg > bufp->re_nsub || reg < 1
3581 /* Can't back reference to a subexp before its end. */
3582 || group_in_compile_stack (compile_stack, reg))
3583 FREE_STACK_RETURN (REG_ESUBREG);
3585 laststart = b;
3586 BUF_PUSH_2 (duplicate, reg);
3588 break;
3591 case '+':
3592 case '?':
3593 if (syntax & RE_BK_PLUS_QM)
3594 goto handle_plus;
3595 else
3596 goto normal_backslash;
3598 default:
3599 normal_backslash:
3600 /* You might think it would be useful for \ to mean
3601 not to translate; but if we don't translate it
3602 it will never match anything. */
3603 goto normal_char;
3605 break;
3608 default:
3609 /* Expects the character in `c'. */
3610 normal_char:
3611 /* If no exactn currently being built. */
3612 if (!pending_exact
3614 /* If last exactn not at current position. */
3615 || pending_exact + *pending_exact + 1 != b
3617 /* We have only one byte following the exactn for the count. */
3618 || *pending_exact >= (1 << BYTEWIDTH) - MAX_MULTIBYTE_LENGTH
3620 /* If followed by a repetition operator. */
3621 || (p != pend && (*p == '*' || *p == '^'))
3622 || ((syntax & RE_BK_PLUS_QM)
3623 ? p + 1 < pend && *p == '\\' && (p[1] == '+' || p[1] == '?')
3624 : p != pend && (*p == '+' || *p == '?'))
3625 || ((syntax & RE_INTERVALS)
3626 && ((syntax & RE_NO_BK_BRACES)
3627 ? p != pend && *p == '{'
3628 : p + 1 < pend && p[0] == '\\' && p[1] == '{')))
3630 /* Start building a new exactn. */
3632 laststart = b;
3634 BUF_PUSH_2 (exactn, 0);
3635 pending_exact = b - 1;
3638 GET_BUFFER_SPACE (MAX_MULTIBYTE_LENGTH);
3640 int len;
3642 if (multibyte)
3644 c = TRANSLATE (c);
3645 len = CHAR_STRING (c, b);
3646 b += len;
3648 else
3650 c1 = RE_CHAR_TO_MULTIBYTE (c);
3651 if (! CHAR_BYTE8_P (c1))
3653 re_wchar_t c2 = TRANSLATE (c1);
3655 if (c1 != c2 && (c1 = RE_CHAR_TO_UNIBYTE (c2)) >= 0)
3656 c = c1;
3658 *b++ = c;
3659 len = 1;
3661 (*pending_exact) += len;
3664 break;
3665 } /* switch (c) */
3666 } /* while p != pend */
3669 /* Through the pattern now. */
3671 FIXUP_ALT_JUMP ();
3673 if (!COMPILE_STACK_EMPTY)
3674 FREE_STACK_RETURN (REG_EPAREN);
3676 /* If we don't want backtracking, force success
3677 the first time we reach the end of the compiled pattern. */
3678 if (syntax & RE_NO_POSIX_BACKTRACKING)
3679 BUF_PUSH (succeed);
3681 /* We have succeeded; set the length of the buffer. */
3682 bufp->used = b - bufp->buffer;
3684 #ifdef DEBUG
3685 if (debug > 0)
3687 re_compile_fastmap (bufp);
3688 DEBUG_PRINT ("\nCompiled pattern: \n");
3689 print_compiled_pattern (bufp);
3691 debug--;
3692 #endif /* DEBUG */
3694 #ifndef MATCH_MAY_ALLOCATE
3695 /* Initialize the failure stack to the largest possible stack. This
3696 isn't necessary unless we're trying to avoid calling alloca in
3697 the search and match routines. */
3699 int num_regs = bufp->re_nsub + 1;
3701 if (fail_stack.size < re_max_failures * TYPICAL_FAILURE_SIZE)
3703 fail_stack.size = re_max_failures * TYPICAL_FAILURE_SIZE;
3704 falk_stack.stack = realloc (fail_stack.stack,
3705 fail_stack.size * sizeof *falk_stack.stack);
3708 regex_grow_registers (num_regs);
3710 #endif /* not MATCH_MAY_ALLOCATE */
3712 FREE_STACK_RETURN (REG_NOERROR);
3713 } /* regex_compile */
3715 /* Subroutines for `regex_compile'. */
3717 /* Store OP at LOC followed by two-byte integer parameter ARG. */
3719 static void
3720 store_op1 (re_opcode_t op, unsigned char *loc, int arg)
3722 *loc = (unsigned char) op;
3723 STORE_NUMBER (loc + 1, arg);
3727 /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
3729 static void
3730 store_op2 (re_opcode_t op, unsigned char *loc, int arg1, int arg2)
3732 *loc = (unsigned char) op;
3733 STORE_NUMBER (loc + 1, arg1);
3734 STORE_NUMBER (loc + 3, arg2);
3738 /* Copy the bytes from LOC to END to open up three bytes of space at LOC
3739 for OP followed by two-byte integer parameter ARG. */
3741 static void
3742 insert_op1 (re_opcode_t op, unsigned char *loc, int arg, unsigned char *end)
3744 register unsigned char *pfrom = end;
3745 register unsigned char *pto = end + 3;
3747 while (pfrom != loc)
3748 *--pto = *--pfrom;
3750 store_op1 (op, loc, arg);
3754 /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
3756 static void
3757 insert_op2 (re_opcode_t op, unsigned char *loc, int arg1, int arg2, unsigned char *end)
3759 register unsigned char *pfrom = end;
3760 register unsigned char *pto = end + 5;
3762 while (pfrom != loc)
3763 *--pto = *--pfrom;
3765 store_op2 (op, loc, arg1, arg2);
3769 /* P points to just after a ^ in PATTERN. Return true if that ^ comes
3770 after an alternative or a begin-subexpression. We assume there is at
3771 least one character before the ^. */
3773 static boolean
3774 at_begline_loc_p (const_re_char *pattern, const_re_char *p, reg_syntax_t syntax)
3776 re_char *prev = p - 2;
3777 boolean odd_backslashes;
3779 /* After a subexpression? */
3780 if (*prev == '(')
3781 odd_backslashes = (syntax & RE_NO_BK_PARENS) == 0;
3783 /* After an alternative? */
3784 else if (*prev == '|')
3785 odd_backslashes = (syntax & RE_NO_BK_VBAR) == 0;
3787 /* After a shy subexpression? */
3788 else if (*prev == ':' && (syntax & RE_SHY_GROUPS))
3790 /* Skip over optional regnum. */
3791 while (prev - 1 >= pattern && prev[-1] >= '0' && prev[-1] <= '9')
3792 --prev;
3794 if (!(prev - 2 >= pattern
3795 && prev[-1] == '?' && prev[-2] == '('))
3796 return false;
3797 prev -= 2;
3798 odd_backslashes = (syntax & RE_NO_BK_PARENS) == 0;
3800 else
3801 return false;
3803 /* Count the number of preceding backslashes. */
3804 p = prev;
3805 while (prev - 1 >= pattern && prev[-1] == '\\')
3806 --prev;
3807 return (p - prev) & odd_backslashes;
3811 /* The dual of at_begline_loc_p. This one is for $. We assume there is
3812 at least one character after the $, i.e., `P < PEND'. */
3814 static boolean
3815 at_endline_loc_p (const_re_char *p, const_re_char *pend, reg_syntax_t syntax)
3817 re_char *next = p;
3818 boolean next_backslash = *next == '\\';
3819 re_char *next_next = p + 1 < pend ? p + 1 : 0;
3821 return
3822 /* Before a subexpression? */
3823 (syntax & RE_NO_BK_PARENS ? *next == ')'
3824 : next_backslash && next_next && *next_next == ')')
3825 /* Before an alternative? */
3826 || (syntax & RE_NO_BK_VBAR ? *next == '|'
3827 : next_backslash && next_next && *next_next == '|');
3831 /* Returns true if REGNUM is in one of COMPILE_STACK's elements and
3832 false if it's not. */
3834 static boolean
3835 group_in_compile_stack (compile_stack_type compile_stack, regnum_t regnum)
3837 ssize_t this_element;
3839 for (this_element = compile_stack.avail - 1;
3840 this_element >= 0;
3841 this_element--)
3842 if (compile_stack.stack[this_element].regnum == regnum)
3843 return true;
3845 return false;
3848 /* analyze_first.
3849 If fastmap is non-NULL, go through the pattern and fill fastmap
3850 with all the possible leading chars. If fastmap is NULL, don't
3851 bother filling it up (obviously) and only return whether the
3852 pattern could potentially match the empty string.
3854 Return 1 if p..pend might match the empty string.
3855 Return 0 if p..pend matches at least one char.
3856 Return -1 if fastmap was not updated accurately. */
3858 static int
3859 analyze_first (const_re_char *p, const_re_char *pend, char *fastmap,
3860 const int multibyte)
3862 int j, k;
3863 boolean not;
3865 /* If all elements for base leading-codes in fastmap is set, this
3866 flag is set true. */
3867 boolean match_any_multibyte_characters = false;
3869 assert (p);
3871 /* The loop below works as follows:
3872 - It has a working-list kept in the PATTERN_STACK and which basically
3873 starts by only containing a pointer to the first operation.
3874 - If the opcode we're looking at is a match against some set of
3875 chars, then we add those chars to the fastmap and go on to the
3876 next work element from the worklist (done via `break').
3877 - If the opcode is a control operator on the other hand, we either
3878 ignore it (if it's meaningless at this point, such as `start_memory')
3879 or execute it (if it's a jump). If the jump has several destinations
3880 (i.e. `on_failure_jump'), then we push the other destination onto the
3881 worklist.
3882 We guarantee termination by ignoring backward jumps (more or less),
3883 so that `p' is monotonically increasing. More to the point, we
3884 never set `p' (or push) anything `<= p1'. */
3886 while (p < pend)
3888 /* `p1' is used as a marker of how far back a `on_failure_jump'
3889 can go without being ignored. It is normally equal to `p'
3890 (which prevents any backward `on_failure_jump') except right
3891 after a plain `jump', to allow patterns such as:
3892 0: jump 10
3893 3..9: <body>
3894 10: on_failure_jump 3
3895 as used for the *? operator. */
3896 re_char *p1 = p;
3898 switch (*p++)
3900 case succeed:
3901 return 1;
3903 case duplicate:
3904 /* If the first character has to match a backreference, that means
3905 that the group was empty (since it already matched). Since this
3906 is the only case that interests us here, we can assume that the
3907 backreference must match the empty string. */
3908 p++;
3909 continue;
3912 /* Following are the cases which match a character. These end
3913 with `break'. */
3915 case exactn:
3916 if (fastmap)
3918 /* If multibyte is nonzero, the first byte of each
3919 character is an ASCII or a leading code. Otherwise,
3920 each byte is a character. Thus, this works in both
3921 cases. */
3922 fastmap[p[1]] = 1;
3923 if (! multibyte)
3925 /* For the case of matching this unibyte regex
3926 against multibyte, we must set a leading code of
3927 the corresponding multibyte character. */
3928 int c = RE_CHAR_TO_MULTIBYTE (p[1]);
3930 fastmap[CHAR_LEADING_CODE (c)] = 1;
3933 break;
3936 case anychar:
3937 /* We could put all the chars except for \n (and maybe \0)
3938 but we don't bother since it is generally not worth it. */
3939 if (!fastmap) break;
3940 return -1;
3943 case charset_not:
3944 if (!fastmap) break;
3946 /* Chars beyond end of bitmap are possible matches. */
3947 for (j = CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH;
3948 j < (1 << BYTEWIDTH); j++)
3949 fastmap[j] = 1;
3952 /* Fallthrough */
3953 case charset:
3954 if (!fastmap) break;
3955 not = (re_opcode_t) *(p - 1) == charset_not;
3956 for (j = CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH - 1, p++;
3957 j >= 0; j--)
3958 if (!!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))) ^ not)
3959 fastmap[j] = 1;
3961 #ifdef emacs
3962 if (/* Any leading code can possibly start a character
3963 which doesn't match the specified set of characters. */
3966 /* If we can match a character class, we can match any
3967 multibyte characters. */
3968 (CHARSET_RANGE_TABLE_EXISTS_P (&p[-2])
3969 && CHARSET_RANGE_TABLE_BITS (&p[-2]) != 0))
3972 if (match_any_multibyte_characters == false)
3974 for (j = MIN_MULTIBYTE_LEADING_CODE;
3975 j <= MAX_MULTIBYTE_LEADING_CODE; j++)
3976 fastmap[j] = 1;
3977 match_any_multibyte_characters = true;
3981 else if (!not && CHARSET_RANGE_TABLE_EXISTS_P (&p[-2])
3982 && match_any_multibyte_characters == false)
3984 /* Set fastmap[I] to 1 where I is a leading code of each
3985 multibyte character in the range table. */
3986 int c, count;
3987 unsigned char lc1, lc2;
3989 /* Make P points the range table. `+ 2' is to skip flag
3990 bits for a character class. */
3991 p += CHARSET_BITMAP_SIZE (&p[-2]) + 2;
3993 /* Extract the number of ranges in range table into COUNT. */
3994 EXTRACT_NUMBER_AND_INCR (count, p);
3995 for (; count > 0; count--, p += 3)
3997 /* Extract the start and end of each range. */
3998 EXTRACT_CHARACTER (c, p);
3999 lc1 = CHAR_LEADING_CODE (c);
4000 p += 3;
4001 EXTRACT_CHARACTER (c, p);
4002 lc2 = CHAR_LEADING_CODE (c);
4003 for (j = lc1; j <= lc2; j++)
4004 fastmap[j] = 1;
4007 #endif
4008 break;
4010 case syntaxspec:
4011 case notsyntaxspec:
4012 if (!fastmap) break;
4013 #ifndef emacs
4014 not = (re_opcode_t)p[-1] == notsyntaxspec;
4015 k = *p++;
4016 for (j = 0; j < (1 << BYTEWIDTH); j++)
4017 if ((SYNTAX (j) == (enum syntaxcode) k) ^ not)
4018 fastmap[j] = 1;
4019 break;
4020 #else /* emacs */
4021 /* This match depends on text properties. These end with
4022 aborting optimizations. */
4023 return -1;
4025 case categoryspec:
4026 case notcategoryspec:
4027 if (!fastmap) break;
4028 not = (re_opcode_t)p[-1] == notcategoryspec;
4029 k = *p++;
4030 for (j = (1 << BYTEWIDTH); j >= 0; j--)
4031 if ((CHAR_HAS_CATEGORY (j, k)) ^ not)
4032 fastmap[j] = 1;
4034 /* Any leading code can possibly start a character which
4035 has or doesn't has the specified category. */
4036 if (match_any_multibyte_characters == false)
4038 for (j = MIN_MULTIBYTE_LEADING_CODE;
4039 j <= MAX_MULTIBYTE_LEADING_CODE; j++)
4040 fastmap[j] = 1;
4041 match_any_multibyte_characters = true;
4043 break;
4045 /* All cases after this match the empty string. These end with
4046 `continue'. */
4048 case before_dot:
4049 case at_dot:
4050 case after_dot:
4051 #endif /* !emacs */
4052 case no_op:
4053 case begline:
4054 case endline:
4055 case begbuf:
4056 case endbuf:
4057 case wordbound:
4058 case notwordbound:
4059 case wordbeg:
4060 case wordend:
4061 case symbeg:
4062 case symend:
4063 continue;
4066 case jump:
4067 EXTRACT_NUMBER_AND_INCR (j, p);
4068 if (j < 0)
4069 /* Backward jumps can only go back to code that we've already
4070 visited. `re_compile' should make sure this is true. */
4071 break;
4072 p += j;
4073 switch (*p)
4075 case on_failure_jump:
4076 case on_failure_keep_string_jump:
4077 case on_failure_jump_loop:
4078 case on_failure_jump_nastyloop:
4079 case on_failure_jump_smart:
4080 p++;
4081 break;
4082 default:
4083 continue;
4085 /* Keep `p1' to allow the `on_failure_jump' we are jumping to
4086 to jump back to "just after here". */
4087 /* Fallthrough */
4089 case on_failure_jump:
4090 case on_failure_keep_string_jump:
4091 case on_failure_jump_nastyloop:
4092 case on_failure_jump_loop:
4093 case on_failure_jump_smart:
4094 EXTRACT_NUMBER_AND_INCR (j, p);
4095 if (p + j <= p1)
4096 ; /* Backward jump to be ignored. */
4097 else
4098 { /* We have to look down both arms.
4099 We first go down the "straight" path so as to minimize
4100 stack usage when going through alternatives. */
4101 int r = analyze_first (p, pend, fastmap, multibyte);
4102 if (r) return r;
4103 p += j;
4105 continue;
4108 case jump_n:
4109 /* This code simply does not properly handle forward jump_n. */
4110 DEBUG_STATEMENT (EXTRACT_NUMBER (j, p); assert (j < 0));
4111 p += 4;
4112 /* jump_n can either jump or fall through. The (backward) jump
4113 case has already been handled, so we only need to look at the
4114 fallthrough case. */
4115 continue;
4117 case succeed_n:
4118 /* If N == 0, it should be an on_failure_jump_loop instead. */
4119 DEBUG_STATEMENT (EXTRACT_NUMBER (j, p + 2); assert (j > 0));
4120 p += 4;
4121 /* We only care about one iteration of the loop, so we don't
4122 need to consider the case where this behaves like an
4123 on_failure_jump. */
4124 continue;
4127 case set_number_at:
4128 p += 4;
4129 continue;
4132 case start_memory:
4133 case stop_memory:
4134 p += 1;
4135 continue;
4138 default:
4139 abort (); /* We have listed all the cases. */
4140 } /* switch *p++ */
4142 /* Getting here means we have found the possible starting
4143 characters for one path of the pattern -- and that the empty
4144 string does not match. We need not follow this path further. */
4145 return 0;
4146 } /* while p */
4148 /* We reached the end without matching anything. */
4149 return 1;
4151 } /* analyze_first */
4153 /* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
4154 BUFP. A fastmap records which of the (1 << BYTEWIDTH) possible
4155 characters can start a string that matches the pattern. This fastmap
4156 is used by re_search to skip quickly over impossible starting points.
4158 Character codes above (1 << BYTEWIDTH) are not represented in the
4159 fastmap, but the leading codes are represented. Thus, the fastmap
4160 indicates which character sets could start a match.
4162 The caller must supply the address of a (1 << BYTEWIDTH)-byte data
4163 area as BUFP->fastmap.
4165 We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
4166 the pattern buffer.
4168 Returns 0 if we succeed, -2 if an internal error. */
4171 re_compile_fastmap (struct re_pattern_buffer *bufp)
4173 char *fastmap = bufp->fastmap;
4174 int analysis;
4176 assert (fastmap && bufp->buffer);
4178 memset (fastmap, 0, 1 << BYTEWIDTH); /* Assume nothing's valid. */
4179 bufp->fastmap_accurate = 1; /* It will be when we're done. */
4181 analysis = analyze_first (bufp->buffer, bufp->buffer + bufp->used,
4182 fastmap, RE_MULTIBYTE_P (bufp));
4183 bufp->can_be_null = (analysis != 0);
4184 return 0;
4185 } /* re_compile_fastmap */
4187 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
4188 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
4189 this memory for recording register information. STARTS and ENDS
4190 must be allocated using the malloc library routine, and must each
4191 be at least NUM_REGS * sizeof (regoff_t) bytes long.
4193 If NUM_REGS == 0, then subsequent matches should allocate their own
4194 register data.
4196 Unless this function is called, the first search or match using
4197 PATTERN_BUFFER will allocate its own register data, without
4198 freeing the old data. */
4200 void
4201 re_set_registers (struct re_pattern_buffer *bufp, struct re_registers *regs, unsigned int num_regs, regoff_t *starts, regoff_t *ends)
4203 if (num_regs)
4205 bufp->regs_allocated = REGS_REALLOCATE;
4206 regs->num_regs = num_regs;
4207 regs->start = starts;
4208 regs->end = ends;
4210 else
4212 bufp->regs_allocated = REGS_UNALLOCATED;
4213 regs->num_regs = 0;
4214 regs->start = regs->end = 0;
4217 WEAK_ALIAS (__re_set_registers, re_set_registers)
4219 /* Searching routines. */
4221 /* Like re_search_2, below, but only one string is specified, and
4222 doesn't let you say where to stop matching. */
4224 regoff_t
4225 re_search (struct re_pattern_buffer *bufp, const char *string, size_t size,
4226 ssize_t startpos, ssize_t range, struct re_registers *regs)
4228 return re_search_2 (bufp, NULL, 0, string, size, startpos, range,
4229 regs, size);
4231 WEAK_ALIAS (__re_search, re_search)
4233 /* Head address of virtual concatenation of string. */
4234 #define HEAD_ADDR_VSTRING(P) \
4235 (((P) >= size1 ? string2 : string1))
4237 /* Address of POS in the concatenation of virtual string. */
4238 #define POS_ADDR_VSTRING(POS) \
4239 (((POS) >= size1 ? string2 - size1 : string1) + (POS))
4241 /* Using the compiled pattern in BUFP->buffer, first tries to match the
4242 virtual concatenation of STRING1 and STRING2, starting first at index
4243 STARTPOS, then at STARTPOS + 1, and so on.
4245 STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
4247 RANGE is how far to scan while trying to match. RANGE = 0 means try
4248 only at STARTPOS; in general, the last start tried is STARTPOS +
4249 RANGE.
4251 In REGS, return the indices of the virtual concatenation of STRING1
4252 and STRING2 that matched the entire BUFP->buffer and its contained
4253 subexpressions.
4255 Do not consider matching one past the index STOP in the virtual
4256 concatenation of STRING1 and STRING2.
4258 We return either the position in the strings at which the match was
4259 found, -1 if no match, or -2 if error (such as failure
4260 stack overflow). */
4262 regoff_t
4263 re_search_2 (struct re_pattern_buffer *bufp, const char *str1, size_t size1,
4264 const char *str2, size_t size2, ssize_t startpos, ssize_t range,
4265 struct re_registers *regs, ssize_t stop)
4267 regoff_t val;
4268 re_char *string1 = (re_char*) str1;
4269 re_char *string2 = (re_char*) str2;
4270 register char *fastmap = bufp->fastmap;
4271 register RE_TRANSLATE_TYPE translate = bufp->translate;
4272 size_t total_size = size1 + size2;
4273 ssize_t endpos = startpos + range;
4274 boolean anchored_start;
4275 /* Nonzero if we are searching multibyte string. */
4276 const boolean multibyte = RE_TARGET_MULTIBYTE_P (bufp);
4278 /* Check for out-of-range STARTPOS. */
4279 if (startpos < 0 || startpos > total_size)
4280 return -1;
4282 /* Fix up RANGE if it might eventually take us outside
4283 the virtual concatenation of STRING1 and STRING2.
4284 Make sure we won't move STARTPOS below 0 or above TOTAL_SIZE. */
4285 if (endpos < 0)
4286 range = 0 - startpos;
4287 else if (endpos > total_size)
4288 range = total_size - startpos;
4290 /* If the search isn't to be a backwards one, don't waste time in a
4291 search for a pattern anchored at beginning of buffer. */
4292 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == begbuf && range > 0)
4294 if (startpos > 0)
4295 return -1;
4296 else
4297 range = 0;
4300 #ifdef emacs
4301 /* In a forward search for something that starts with \=.
4302 don't keep searching past point. */
4303 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == at_dot && range > 0)
4305 range = PT_BYTE - BEGV_BYTE - startpos;
4306 if (range < 0)
4307 return -1;
4309 #endif /* emacs */
4311 /* Update the fastmap now if not correct already. */
4312 if (fastmap && !bufp->fastmap_accurate)
4313 re_compile_fastmap (bufp);
4315 /* See whether the pattern is anchored. */
4316 anchored_start = (bufp->buffer[0] == begline);
4318 #ifdef emacs
4319 gl_state.object = re_match_object; /* Used by SYNTAX_TABLE_BYTE_TO_CHAR. */
4321 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (POS_AS_IN_BUFFER (startpos));
4323 SETUP_SYNTAX_TABLE_FOR_OBJECT (re_match_object, charpos, 1);
4325 #endif
4327 /* Loop through the string, looking for a place to start matching. */
4328 for (;;)
4330 /* If the pattern is anchored,
4331 skip quickly past places we cannot match.
4332 We don't bother to treat startpos == 0 specially
4333 because that case doesn't repeat. */
4334 if (anchored_start && startpos > 0)
4336 if (! ((startpos <= size1 ? string1[startpos - 1]
4337 : string2[startpos - size1 - 1])
4338 == '\n'))
4339 goto advance;
4342 /* If a fastmap is supplied, skip quickly over characters that
4343 cannot be the start of a match. If the pattern can match the
4344 null string, however, we don't need to skip characters; we want
4345 the first null string. */
4346 if (fastmap && startpos < total_size && !bufp->can_be_null)
4348 register re_char *d;
4349 register re_wchar_t buf_ch;
4351 d = POS_ADDR_VSTRING (startpos);
4353 if (range > 0) /* Searching forwards. */
4355 ssize_t irange = range, lim = 0;
4357 if (startpos < size1 && startpos + range >= size1)
4358 lim = range - (size1 - startpos);
4360 /* Written out as an if-else to avoid testing `translate'
4361 inside the loop. */
4362 if (RE_TRANSLATE_P (translate))
4364 if (multibyte)
4365 while (range > lim)
4367 int buf_charlen;
4369 buf_ch = STRING_CHAR_AND_LENGTH (d, buf_charlen);
4370 buf_ch = RE_TRANSLATE (translate, buf_ch);
4371 if (fastmap[CHAR_LEADING_CODE (buf_ch)])
4372 break;
4374 range -= buf_charlen;
4375 d += buf_charlen;
4377 else
4378 while (range > lim)
4380 register re_wchar_t ch, translated;
4382 buf_ch = *d;
4383 ch = RE_CHAR_TO_MULTIBYTE (buf_ch);
4384 translated = RE_TRANSLATE (translate, ch);
4385 if (translated != ch
4386 && (ch = RE_CHAR_TO_UNIBYTE (translated)) >= 0)
4387 buf_ch = ch;
4388 if (fastmap[buf_ch])
4389 break;
4390 d++;
4391 range--;
4394 else
4396 if (multibyte)
4397 while (range > lim)
4399 int buf_charlen;
4401 buf_ch = STRING_CHAR_AND_LENGTH (d, buf_charlen);
4402 if (fastmap[CHAR_LEADING_CODE (buf_ch)])
4403 break;
4404 range -= buf_charlen;
4405 d += buf_charlen;
4407 else
4408 while (range > lim && !fastmap[*d])
4410 d++;
4411 range--;
4414 startpos += irange - range;
4416 else /* Searching backwards. */
4418 if (multibyte)
4420 buf_ch = STRING_CHAR (d);
4421 buf_ch = TRANSLATE (buf_ch);
4422 if (! fastmap[CHAR_LEADING_CODE (buf_ch)])
4423 goto advance;
4425 else
4427 register re_wchar_t ch, translated;
4429 buf_ch = *d;
4430 ch = RE_CHAR_TO_MULTIBYTE (buf_ch);
4431 translated = TRANSLATE (ch);
4432 if (translated != ch
4433 && (ch = RE_CHAR_TO_UNIBYTE (translated)) >= 0)
4434 buf_ch = ch;
4435 if (! fastmap[TRANSLATE (buf_ch)])
4436 goto advance;
4441 /* If can't match the null string, and that's all we have left, fail. */
4442 if (range >= 0 && startpos == total_size && fastmap
4443 && !bufp->can_be_null)
4444 return -1;
4446 val = re_match_2_internal (bufp, string1, size1, string2, size2,
4447 startpos, regs, stop);
4449 if (val >= 0)
4450 return startpos;
4452 if (val == -2)
4453 return -2;
4455 advance:
4456 if (!range)
4457 break;
4458 else if (range > 0)
4460 /* Update STARTPOS to the next character boundary. */
4461 if (multibyte)
4463 re_char *p = POS_ADDR_VSTRING (startpos);
4464 int len = BYTES_BY_CHAR_HEAD (*p);
4466 range -= len;
4467 if (range < 0)
4468 break;
4469 startpos += len;
4471 else
4473 range--;
4474 startpos++;
4477 else
4479 range++;
4480 startpos--;
4482 /* Update STARTPOS to the previous character boundary. */
4483 if (multibyte)
4485 re_char *p = POS_ADDR_VSTRING (startpos) + 1;
4486 re_char *p0 = p;
4487 re_char *phead = HEAD_ADDR_VSTRING (startpos);
4489 /* Find the head of multibyte form. */
4490 PREV_CHAR_BOUNDARY (p, phead);
4491 range += p0 - 1 - p;
4492 if (range > 0)
4493 break;
4495 startpos -= p0 - 1 - p;
4499 return -1;
4500 } /* re_search_2 */
4501 WEAK_ALIAS (__re_search_2, re_search_2)
4503 /* Declarations and macros for re_match_2. */
4505 static int bcmp_translate (re_char *s1, re_char *s2,
4506 register ssize_t len,
4507 RE_TRANSLATE_TYPE translate,
4508 const int multibyte);
4510 /* This converts PTR, a pointer into one of the search strings `string1'
4511 and `string2' into an offset from the beginning of that string. */
4512 #define POINTER_TO_OFFSET(ptr) \
4513 (FIRST_STRING_P (ptr) \
4514 ? (ptr) - string1 \
4515 : (ptr) - string2 + (ptrdiff_t) size1)
4517 /* Call before fetching a character with *d. This switches over to
4518 string2 if necessary.
4519 Check re_match_2_internal for a discussion of why end_match_2 might
4520 not be within string2 (but be equal to end_match_1 instead). */
4521 #define PREFETCH() \
4522 while (d == dend) \
4524 /* End of string2 => fail. */ \
4525 if (dend == end_match_2) \
4526 goto fail; \
4527 /* End of string1 => advance to string2. */ \
4528 d = string2; \
4529 dend = end_match_2; \
4532 /* Call before fetching a char with *d if you already checked other limits.
4533 This is meant for use in lookahead operations like wordend, etc..
4534 where we might need to look at parts of the string that might be
4535 outside of the LIMITs (i.e past `stop'). */
4536 #define PREFETCH_NOLIMIT() \
4537 if (d == end1) \
4539 d = string2; \
4540 dend = end_match_2; \
4543 /* Test if at very beginning or at very end of the virtual concatenation
4544 of `string1' and `string2'. If only one string, it's `string2'. */
4545 #define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
4546 #define AT_STRINGS_END(d) ((d) == end2)
4548 /* Disabled due to a compiler bug -- see comment at case wordbound */
4550 /* The comment at case wordbound is following one, but we don't use
4551 AT_WORD_BOUNDARY anymore to support multibyte form.
4553 The DEC Alpha C compiler 3.x generates incorrect code for the
4554 test WORDCHAR_P (d - 1) != WORDCHAR_P (d) in the expansion of
4555 AT_WORD_BOUNDARY, so this code is disabled. Expanding the
4556 macro and introducing temporary variables works around the bug. */
4558 #if 0
4559 /* Test if D points to a character which is word-constituent. We have
4560 two special cases to check for: if past the end of string1, look at
4561 the first character in string2; and if before the beginning of
4562 string2, look at the last character in string1. */
4563 #define WORDCHAR_P(d) \
4564 (SYNTAX ((d) == end1 ? *string2 \
4565 : (d) == string2 - 1 ? *(end1 - 1) : *(d)) \
4566 == Sword)
4568 /* Test if the character before D and the one at D differ with respect
4569 to being word-constituent. */
4570 #define AT_WORD_BOUNDARY(d) \
4571 (AT_STRINGS_BEG (d) || AT_STRINGS_END (d) \
4572 || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
4573 #endif
4575 /* Free everything we malloc. */
4576 #ifdef MATCH_MAY_ALLOCATE
4577 # define FREE_VAR(var) \
4578 do { \
4579 if (var) \
4581 REGEX_FREE (var); \
4582 var = NULL; \
4584 } while (0)
4585 # define FREE_VARIABLES() \
4586 do { \
4587 REGEX_FREE_STACK (fail_stack.stack); \
4588 FREE_VAR (regstart); \
4589 FREE_VAR (regend); \
4590 FREE_VAR (best_regstart); \
4591 FREE_VAR (best_regend); \
4592 REGEX_SAFE_FREE (); \
4593 } while (0)
4594 #else
4595 # define FREE_VARIABLES() ((void)0) /* Do nothing! But inhibit gcc warning. */
4596 #endif /* not MATCH_MAY_ALLOCATE */
4599 /* Optimization routines. */
4601 /* If the operation is a match against one or more chars,
4602 return a pointer to the next operation, else return NULL. */
4603 static re_char *
4604 skip_one_char (const_re_char *p)
4606 switch (*p++)
4608 case anychar:
4609 break;
4611 case exactn:
4612 p += *p + 1;
4613 break;
4615 case charset_not:
4616 case charset:
4617 if (CHARSET_RANGE_TABLE_EXISTS_P (p - 1))
4619 int mcnt;
4620 p = CHARSET_RANGE_TABLE (p - 1);
4621 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4622 p = CHARSET_RANGE_TABLE_END (p, mcnt);
4624 else
4625 p += 1 + CHARSET_BITMAP_SIZE (p - 1);
4626 break;
4628 case syntaxspec:
4629 case notsyntaxspec:
4630 #ifdef emacs
4631 case categoryspec:
4632 case notcategoryspec:
4633 #endif /* emacs */
4634 p++;
4635 break;
4637 default:
4638 p = NULL;
4640 return p;
4644 /* Jump over non-matching operations. */
4645 static re_char *
4646 skip_noops (const_re_char *p, const_re_char *pend)
4648 int mcnt;
4649 while (p < pend)
4651 switch (*p)
4653 case start_memory:
4654 case stop_memory:
4655 p += 2; break;
4656 case no_op:
4657 p += 1; break;
4658 case jump:
4659 p += 1;
4660 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4661 p += mcnt;
4662 break;
4663 default:
4664 return p;
4667 assert (p == pend);
4668 return p;
4671 /* Non-zero if "p1 matches something" implies "p2 fails". */
4672 static int
4673 mutually_exclusive_p (struct re_pattern_buffer *bufp, const_re_char *p1,
4674 const_re_char *p2)
4676 re_opcode_t op2;
4677 const boolean multibyte = RE_MULTIBYTE_P (bufp);
4678 unsigned char *pend = bufp->buffer + bufp->used;
4680 assert (p1 >= bufp->buffer && p1 < pend
4681 && p2 >= bufp->buffer && p2 <= pend);
4683 /* Skip over open/close-group commands.
4684 If what follows this loop is a ...+ construct,
4685 look at what begins its body, since we will have to
4686 match at least one of that. */
4687 p2 = skip_noops (p2, pend);
4688 /* The same skip can be done for p1, except that this function
4689 is only used in the case where p1 is a simple match operator. */
4690 /* p1 = skip_noops (p1, pend); */
4692 assert (p1 >= bufp->buffer && p1 < pend
4693 && p2 >= bufp->buffer && p2 <= pend);
4695 op2 = p2 == pend ? succeed : *p2;
4697 switch (op2)
4699 case succeed:
4700 case endbuf:
4701 /* If we're at the end of the pattern, we can change. */
4702 if (skip_one_char (p1))
4704 DEBUG_PRINT (" End of pattern: fast loop.\n");
4705 return 1;
4707 break;
4709 case endline:
4710 case exactn:
4712 register re_wchar_t c
4713 = (re_opcode_t) *p2 == endline ? '\n'
4714 : RE_STRING_CHAR (p2 + 2, multibyte);
4716 if ((re_opcode_t) *p1 == exactn)
4718 if (c != RE_STRING_CHAR (p1 + 2, multibyte))
4720 DEBUG_PRINT (" '%c' != '%c' => fast loop.\n", c, p1[2]);
4721 return 1;
4725 else if ((re_opcode_t) *p1 == charset
4726 || (re_opcode_t) *p1 == charset_not)
4728 int not = (re_opcode_t) *p1 == charset_not;
4730 /* Test if C is listed in charset (or charset_not)
4731 at `p1'. */
4732 if (! multibyte || IS_REAL_ASCII (c))
4734 if (c < CHARSET_BITMAP_SIZE (p1) * BYTEWIDTH
4735 && p1[2 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4736 not = !not;
4738 else if (CHARSET_RANGE_TABLE_EXISTS_P (p1))
4739 CHARSET_LOOKUP_RANGE_TABLE (not, c, p1);
4741 /* `not' is equal to 1 if c would match, which means
4742 that we can't change to pop_failure_jump. */
4743 if (!not)
4745 DEBUG_PRINT (" No match => fast loop.\n");
4746 return 1;
4749 else if ((re_opcode_t) *p1 == anychar
4750 && c == '\n')
4752 DEBUG_PRINT (" . != \\n => fast loop.\n");
4753 return 1;
4756 break;
4758 case charset:
4760 if ((re_opcode_t) *p1 == exactn)
4761 /* Reuse the code above. */
4762 return mutually_exclusive_p (bufp, p2, p1);
4764 /* It is hard to list up all the character in charset
4765 P2 if it includes multibyte character. Give up in
4766 such case. */
4767 else if (!multibyte || !CHARSET_RANGE_TABLE_EXISTS_P (p2))
4769 /* Now, we are sure that P2 has no range table.
4770 So, for the size of bitmap in P2, `p2[1]' is
4771 enough. But P1 may have range table, so the
4772 size of bitmap table of P1 is extracted by
4773 using macro `CHARSET_BITMAP_SIZE'.
4775 In a multibyte case, we know that all the character
4776 listed in P2 is ASCII. In a unibyte case, P1 has only a
4777 bitmap table. So, in both cases, it is enough to test
4778 only the bitmap table of P1. */
4780 if ((re_opcode_t) *p1 == charset)
4782 int idx;
4783 /* We win if the charset inside the loop
4784 has no overlap with the one after the loop. */
4785 for (idx = 0;
4786 (idx < (int) p2[1]
4787 && idx < CHARSET_BITMAP_SIZE (p1));
4788 idx++)
4789 if ((p2[2 + idx] & p1[2 + idx]) != 0)
4790 break;
4792 if (idx == p2[1]
4793 || idx == CHARSET_BITMAP_SIZE (p1))
4795 DEBUG_PRINT (" No match => fast loop.\n");
4796 return 1;
4799 else if ((re_opcode_t) *p1 == charset_not)
4801 int idx;
4802 /* We win if the charset_not inside the loop lists
4803 every character listed in the charset after. */
4804 for (idx = 0; idx < (int) p2[1]; idx++)
4805 if (! (p2[2 + idx] == 0
4806 || (idx < CHARSET_BITMAP_SIZE (p1)
4807 && ((p2[2 + idx] & ~ p1[2 + idx]) == 0))))
4808 break;
4810 if (idx == p2[1])
4812 DEBUG_PRINT (" No match => fast loop.\n");
4813 return 1;
4818 break;
4820 case charset_not:
4821 switch (*p1)
4823 case exactn:
4824 case charset:
4825 /* Reuse the code above. */
4826 return mutually_exclusive_p (bufp, p2, p1);
4827 case charset_not:
4828 /* When we have two charset_not, it's very unlikely that
4829 they don't overlap. The union of the two sets of excluded
4830 chars should cover all possible chars, which, as a matter of
4831 fact, is virtually impossible in multibyte buffers. */
4832 break;
4834 break;
4836 case wordend:
4837 return ((re_opcode_t) *p1 == syntaxspec && p1[1] == Sword);
4838 case symend:
4839 return ((re_opcode_t) *p1 == syntaxspec
4840 && (p1[1] == Ssymbol || p1[1] == Sword));
4841 case notsyntaxspec:
4842 return ((re_opcode_t) *p1 == syntaxspec && p1[1] == p2[1]);
4844 case wordbeg:
4845 return ((re_opcode_t) *p1 == notsyntaxspec && p1[1] == Sword);
4846 case symbeg:
4847 return ((re_opcode_t) *p1 == notsyntaxspec
4848 && (p1[1] == Ssymbol || p1[1] == Sword));
4849 case syntaxspec:
4850 return ((re_opcode_t) *p1 == notsyntaxspec && p1[1] == p2[1]);
4852 case wordbound:
4853 return (((re_opcode_t) *p1 == notsyntaxspec
4854 || (re_opcode_t) *p1 == syntaxspec)
4855 && p1[1] == Sword);
4857 #ifdef emacs
4858 case categoryspec:
4859 return ((re_opcode_t) *p1 == notcategoryspec && p1[1] == p2[1]);
4860 case notcategoryspec:
4861 return ((re_opcode_t) *p1 == categoryspec && p1[1] == p2[1]);
4862 #endif /* emacs */
4864 default:
4868 /* Safe default. */
4869 return 0;
4873 /* Matching routines. */
4875 #ifndef emacs /* Emacs never uses this. */
4876 /* re_match is like re_match_2 except it takes only a single string. */
4878 regoff_t
4879 re_match (struct re_pattern_buffer *bufp, const char *string,
4880 size_t size, ssize_t pos, struct re_registers *regs)
4882 regoff_t result = re_match_2_internal (bufp, NULL, 0, (re_char*) string,
4883 size, pos, regs, size);
4884 return result;
4886 WEAK_ALIAS (__re_match, re_match)
4887 #endif /* not emacs */
4889 #ifdef emacs
4890 /* In Emacs, this is the string or buffer in which we
4891 are matching. It is used for looking up syntax properties. */
4892 Lisp_Object re_match_object;
4893 #endif
4895 /* re_match_2 matches the compiled pattern in BUFP against the
4896 the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
4897 and SIZE2, respectively). We start matching at POS, and stop
4898 matching at STOP.
4900 If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
4901 store offsets for the substring each group matched in REGS. See the
4902 documentation for exactly how many groups we fill.
4904 We return -1 if no match, -2 if an internal error (such as the
4905 failure stack overflowing). Otherwise, we return the length of the
4906 matched substring. */
4908 regoff_t
4909 re_match_2 (struct re_pattern_buffer *bufp, const char *string1,
4910 size_t size1, const char *string2, size_t size2, ssize_t pos,
4911 struct re_registers *regs, ssize_t stop)
4913 regoff_t result;
4915 #ifdef emacs
4916 ssize_t charpos;
4917 gl_state.object = re_match_object; /* Used by SYNTAX_TABLE_BYTE_TO_CHAR. */
4918 charpos = SYNTAX_TABLE_BYTE_TO_CHAR (POS_AS_IN_BUFFER (pos));
4919 SETUP_SYNTAX_TABLE_FOR_OBJECT (re_match_object, charpos, 1);
4920 #endif
4922 result = re_match_2_internal (bufp, (re_char*) string1, size1,
4923 (re_char*) string2, size2,
4924 pos, regs, stop);
4925 return result;
4927 WEAK_ALIAS (__re_match_2, re_match_2)
4930 /* This is a separate function so that we can force an alloca cleanup
4931 afterwards. */
4932 static regoff_t
4933 re_match_2_internal (struct re_pattern_buffer *bufp, const_re_char *string1,
4934 size_t size1, const_re_char *string2, size_t size2,
4935 ssize_t pos, struct re_registers *regs, ssize_t stop)
4937 /* General temporaries. */
4938 int mcnt;
4939 size_t reg;
4941 /* Just past the end of the corresponding string. */
4942 re_char *end1, *end2;
4944 /* Pointers into string1 and string2, just past the last characters in
4945 each to consider matching. */
4946 re_char *end_match_1, *end_match_2;
4948 /* Where we are in the data, and the end of the current string. */
4949 re_char *d, *dend;
4951 /* Used sometimes to remember where we were before starting matching
4952 an operator so that we can go back in case of failure. This "atomic"
4953 behavior of matching opcodes is indispensable to the correctness
4954 of the on_failure_keep_string_jump optimization. */
4955 re_char *dfail;
4957 /* Where we are in the pattern, and the end of the pattern. */
4958 re_char *p = bufp->buffer;
4959 re_char *pend = p + bufp->used;
4961 /* We use this to map every character in the string. */
4962 RE_TRANSLATE_TYPE translate = bufp->translate;
4964 /* Nonzero if BUFP is setup from a multibyte regex. */
4965 const boolean multibyte = RE_MULTIBYTE_P (bufp);
4967 /* Nonzero if STRING1/STRING2 are multibyte. */
4968 const boolean target_multibyte = RE_TARGET_MULTIBYTE_P (bufp);
4970 /* Failure point stack. Each place that can handle a failure further
4971 down the line pushes a failure point on this stack. It consists of
4972 regstart, and regend for all registers corresponding to
4973 the subexpressions we're currently inside, plus the number of such
4974 registers, and, finally, two char *'s. The first char * is where
4975 to resume scanning the pattern; the second one is where to resume
4976 scanning the strings. */
4977 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
4978 fail_stack_type fail_stack;
4979 #endif
4980 #ifdef DEBUG_COMPILES_ARGUMENTS
4981 unsigned nfailure_points_pushed = 0, nfailure_points_popped = 0;
4982 #endif
4984 #if defined REL_ALLOC && defined REGEX_MALLOC
4985 /* This holds the pointer to the failure stack, when
4986 it is allocated relocatably. */
4987 fail_stack_elt_t *failure_stack_ptr;
4988 #endif
4990 /* We fill all the registers internally, independent of what we
4991 return, for use in backreferences. The number here includes
4992 an element for register zero. */
4993 size_t num_regs = bufp->re_nsub + 1;
4995 /* Information on the contents of registers. These are pointers into
4996 the input strings; they record just what was matched (on this
4997 attempt) by a subexpression part of the pattern, that is, the
4998 regnum-th regstart pointer points to where in the pattern we began
4999 matching and the regnum-th regend points to right after where we
5000 stopped matching the regnum-th subexpression. (The zeroth register
5001 keeps track of what the whole pattern matches.) */
5002 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
5003 re_char **regstart, **regend;
5004 #endif
5006 /* The following record the register info as found in the above
5007 variables when we find a match better than any we've seen before.
5008 This happens as we backtrack through the failure points, which in
5009 turn happens only if we have not yet matched the entire string. */
5010 unsigned best_regs_set = false;
5011 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
5012 re_char **best_regstart, **best_regend;
5013 #endif
5015 /* Logically, this is `best_regend[0]'. But we don't want to have to
5016 allocate space for that if we're not allocating space for anything
5017 else (see below). Also, we never need info about register 0 for
5018 any of the other register vectors, and it seems rather a kludge to
5019 treat `best_regend' differently than the rest. So we keep track of
5020 the end of the best match so far in a separate variable. We
5021 initialize this to NULL so that when we backtrack the first time
5022 and need to test it, it's not garbage. */
5023 re_char *match_end = NULL;
5025 #ifdef DEBUG_COMPILES_ARGUMENTS
5026 /* Counts the total number of registers pushed. */
5027 unsigned num_regs_pushed = 0;
5028 #endif
5030 DEBUG_PRINT ("\n\nEntering re_match_2.\n");
5032 REGEX_USE_SAFE_ALLOCA;
5034 INIT_FAIL_STACK ();
5036 #ifdef MATCH_MAY_ALLOCATE
5037 /* Do not bother to initialize all the register variables if there are
5038 no groups in the pattern, as it takes a fair amount of time. If
5039 there are groups, we include space for register 0 (the whole
5040 pattern), even though we never use it, since it simplifies the
5041 array indexing. We should fix this. */
5042 if (bufp->re_nsub)
5044 regstart = REGEX_TALLOC (num_regs, re_char *);
5045 regend = REGEX_TALLOC (num_regs, re_char *);
5046 best_regstart = REGEX_TALLOC (num_regs, re_char *);
5047 best_regend = REGEX_TALLOC (num_regs, re_char *);
5049 if (!(regstart && regend && best_regstart && best_regend))
5051 FREE_VARIABLES ();
5052 return -2;
5055 else
5057 /* We must initialize all our variables to NULL, so that
5058 `FREE_VARIABLES' doesn't try to free them. */
5059 regstart = regend = best_regstart = best_regend = NULL;
5061 #endif /* MATCH_MAY_ALLOCATE */
5063 /* The starting position is bogus. */
5064 if (pos < 0 || pos > size1 + size2)
5066 FREE_VARIABLES ();
5067 return -1;
5070 /* Initialize subexpression text positions to -1 to mark ones that no
5071 start_memory/stop_memory has been seen for. Also initialize the
5072 register information struct. */
5073 for (reg = 1; reg < num_regs; reg++)
5074 regstart[reg] = regend[reg] = NULL;
5076 /* We move `string1' into `string2' if the latter's empty -- but not if
5077 `string1' is null. */
5078 if (size2 == 0 && string1 != NULL)
5080 string2 = string1;
5081 size2 = size1;
5082 string1 = 0;
5083 size1 = 0;
5085 end1 = string1 + size1;
5086 end2 = string2 + size2;
5088 /* `p' scans through the pattern as `d' scans through the data.
5089 `dend' is the end of the input string that `d' points within. `d'
5090 is advanced into the following input string whenever necessary, but
5091 this happens before fetching; therefore, at the beginning of the
5092 loop, `d' can be pointing at the end of a string, but it cannot
5093 equal `string2'. */
5094 if (pos >= size1)
5096 /* Only match within string2. */
5097 d = string2 + pos - size1;
5098 dend = end_match_2 = string2 + stop - size1;
5099 end_match_1 = end1; /* Just to give it a value. */
5101 else
5103 if (stop < size1)
5105 /* Only match within string1. */
5106 end_match_1 = string1 + stop;
5107 /* BEWARE!
5108 When we reach end_match_1, PREFETCH normally switches to string2.
5109 But in the present case, this means that just doing a PREFETCH
5110 makes us jump from `stop' to `gap' within the string.
5111 What we really want here is for the search to stop as
5112 soon as we hit end_match_1. That's why we set end_match_2
5113 to end_match_1 (since PREFETCH fails as soon as we hit
5114 end_match_2). */
5115 end_match_2 = end_match_1;
5117 else
5118 { /* It's important to use this code when stop == size so that
5119 moving `d' from end1 to string2 will not prevent the d == dend
5120 check from catching the end of string. */
5121 end_match_1 = end1;
5122 end_match_2 = string2 + stop - size1;
5124 d = string1 + pos;
5125 dend = end_match_1;
5128 DEBUG_PRINT ("The compiled pattern is: ");
5129 DEBUG_PRINT_COMPILED_PATTERN (bufp, p, pend);
5130 DEBUG_PRINT ("The string to match is: `");
5131 DEBUG_PRINT_DOUBLE_STRING (d, string1, size1, string2, size2);
5132 DEBUG_PRINT ("'\n");
5134 /* This loops over pattern commands. It exits by returning from the
5135 function if the match is complete, or it drops through if the match
5136 fails at this starting point in the input data. */
5137 for (;;)
5139 DEBUG_PRINT ("\n%p: ", p);
5141 if (p == pend)
5143 ptrdiff_t dcnt;
5145 /* End of pattern means we might have succeeded. */
5146 DEBUG_PRINT ("end of pattern ... ");
5148 /* If we haven't matched the entire string, and we want the
5149 longest match, try backtracking. */
5150 if (d != end_match_2)
5152 /* 1 if this match ends in the same string (string1 or string2)
5153 as the best previous match. */
5154 boolean same_str_p = (FIRST_STRING_P (match_end)
5155 == FIRST_STRING_P (d));
5156 /* 1 if this match is the best seen so far. */
5157 boolean best_match_p;
5159 /* AIX compiler got confused when this was combined
5160 with the previous declaration. */
5161 if (same_str_p)
5162 best_match_p = d > match_end;
5163 else
5164 best_match_p = !FIRST_STRING_P (d);
5166 DEBUG_PRINT ("backtracking.\n");
5168 if (!FAIL_STACK_EMPTY ())
5169 { /* More failure points to try. */
5171 /* If exceeds best match so far, save it. */
5172 if (!best_regs_set || best_match_p)
5174 best_regs_set = true;
5175 match_end = d;
5177 DEBUG_PRINT ("\nSAVING match as best so far.\n");
5179 for (reg = 1; reg < num_regs; reg++)
5181 best_regstart[reg] = regstart[reg];
5182 best_regend[reg] = regend[reg];
5185 goto fail;
5188 /* If no failure points, don't restore garbage. And if
5189 last match is real best match, don't restore second
5190 best one. */
5191 else if (best_regs_set && !best_match_p)
5193 restore_best_regs:
5194 /* Restore best match. It may happen that `dend ==
5195 end_match_1' while the restored d is in string2.
5196 For example, the pattern `x.*y.*z' against the
5197 strings `x-' and `y-z-', if the two strings are
5198 not consecutive in memory. */
5199 DEBUG_PRINT ("Restoring best registers.\n");
5201 d = match_end;
5202 dend = ((d >= string1 && d <= end1)
5203 ? end_match_1 : end_match_2);
5205 for (reg = 1; reg < num_regs; reg++)
5207 regstart[reg] = best_regstart[reg];
5208 regend[reg] = best_regend[reg];
5211 } /* d != end_match_2 */
5213 succeed_label:
5214 DEBUG_PRINT ("Accepting match.\n");
5216 /* If caller wants register contents data back, do it. */
5217 if (regs && !bufp->no_sub)
5219 /* Have the register data arrays been allocated? */
5220 if (bufp->regs_allocated == REGS_UNALLOCATED)
5221 { /* No. So allocate them with malloc. We need one
5222 extra element beyond `num_regs' for the `-1' marker
5223 GNU code uses. */
5224 regs->num_regs = max (RE_NREGS, num_regs + 1);
5225 regs->start = TALLOC (regs->num_regs, regoff_t);
5226 regs->end = TALLOC (regs->num_regs, regoff_t);
5227 if (regs->start == NULL || regs->end == NULL)
5229 FREE_VARIABLES ();
5230 return -2;
5232 bufp->regs_allocated = REGS_REALLOCATE;
5234 else if (bufp->regs_allocated == REGS_REALLOCATE)
5235 { /* Yes. If we need more elements than were already
5236 allocated, reallocate them. If we need fewer, just
5237 leave it alone. */
5238 if (regs->num_regs < num_regs + 1)
5240 regs->num_regs = num_regs + 1;
5241 RETALLOC (regs->start, regs->num_regs, regoff_t);
5242 RETALLOC (regs->end, regs->num_regs, regoff_t);
5243 if (regs->start == NULL || regs->end == NULL)
5245 FREE_VARIABLES ();
5246 return -2;
5250 else
5252 /* These braces fend off a "empty body in an else-statement"
5253 warning under GCC when assert expands to nothing. */
5254 assert (bufp->regs_allocated == REGS_FIXED);
5257 /* Convert the pointer data in `regstart' and `regend' to
5258 indices. Register zero has to be set differently,
5259 since we haven't kept track of any info for it. */
5260 if (regs->num_regs > 0)
5262 regs->start[0] = pos;
5263 regs->end[0] = POINTER_TO_OFFSET (d);
5266 /* Go through the first `min (num_regs, regs->num_regs)'
5267 registers, since that is all we initialized. */
5268 for (reg = 1; reg < min (num_regs, regs->num_regs); reg++)
5270 if (REG_UNSET (regstart[reg]) || REG_UNSET (regend[reg]))
5271 regs->start[reg] = regs->end[reg] = -1;
5272 else
5274 regs->start[reg] = POINTER_TO_OFFSET (regstart[reg]);
5275 regs->end[reg] = POINTER_TO_OFFSET (regend[reg]);
5279 /* If the regs structure we return has more elements than
5280 were in the pattern, set the extra elements to -1. If
5281 we (re)allocated the registers, this is the case,
5282 because we always allocate enough to have at least one
5283 -1 at the end. */
5284 for (reg = num_regs; reg < regs->num_regs; reg++)
5285 regs->start[reg] = regs->end[reg] = -1;
5286 } /* regs && !bufp->no_sub */
5288 DEBUG_PRINT ("%u failure points pushed, %u popped (%u remain).\n",
5289 nfailure_points_pushed, nfailure_points_popped,
5290 nfailure_points_pushed - nfailure_points_popped);
5291 DEBUG_PRINT ("%u registers pushed.\n", num_regs_pushed);
5293 dcnt = POINTER_TO_OFFSET (d) - pos;
5295 DEBUG_PRINT ("Returning %td from re_match_2.\n", dcnt);
5297 FREE_VARIABLES ();
5298 return dcnt;
5301 /* Otherwise match next pattern command. */
5302 switch (*p++)
5304 /* Ignore these. Used to ignore the n of succeed_n's which
5305 currently have n == 0. */
5306 case no_op:
5307 DEBUG_PRINT ("EXECUTING no_op.\n");
5308 break;
5310 case succeed:
5311 DEBUG_PRINT ("EXECUTING succeed.\n");
5312 goto succeed_label;
5314 /* Match the next n pattern characters exactly. The following
5315 byte in the pattern defines n, and the n bytes after that
5316 are the characters to match. */
5317 case exactn:
5318 mcnt = *p++;
5319 DEBUG_PRINT ("EXECUTING exactn %d.\n", mcnt);
5321 /* Remember the start point to rollback upon failure. */
5322 dfail = d;
5324 #ifndef emacs
5325 /* This is written out as an if-else so we don't waste time
5326 testing `translate' inside the loop. */
5327 if (RE_TRANSLATE_P (translate))
5330 PREFETCH ();
5331 if (RE_TRANSLATE (translate, *d) != *p++)
5333 d = dfail;
5334 goto fail;
5336 d++;
5338 while (--mcnt);
5339 else
5342 PREFETCH ();
5343 if (*d++ != *p++)
5345 d = dfail;
5346 goto fail;
5349 while (--mcnt);
5350 #else /* emacs */
5351 /* The cost of testing `translate' is comparatively small. */
5352 if (target_multibyte)
5355 int pat_charlen, buf_charlen;
5356 int pat_ch, buf_ch;
5358 PREFETCH ();
5359 if (multibyte)
5360 pat_ch = STRING_CHAR_AND_LENGTH (p, pat_charlen);
5361 else
5363 pat_ch = RE_CHAR_TO_MULTIBYTE (*p);
5364 pat_charlen = 1;
5366 buf_ch = STRING_CHAR_AND_LENGTH (d, buf_charlen);
5368 if (TRANSLATE (buf_ch) != pat_ch)
5370 d = dfail;
5371 goto fail;
5374 p += pat_charlen;
5375 d += buf_charlen;
5376 mcnt -= pat_charlen;
5378 while (mcnt > 0);
5379 else
5382 int pat_charlen;
5383 int pat_ch, buf_ch;
5385 PREFETCH ();
5386 if (multibyte)
5388 pat_ch = STRING_CHAR_AND_LENGTH (p, pat_charlen);
5389 pat_ch = RE_CHAR_TO_UNIBYTE (pat_ch);
5391 else
5393 pat_ch = *p;
5394 pat_charlen = 1;
5396 buf_ch = RE_CHAR_TO_MULTIBYTE (*d);
5397 if (! CHAR_BYTE8_P (buf_ch))
5399 buf_ch = TRANSLATE (buf_ch);
5400 buf_ch = RE_CHAR_TO_UNIBYTE (buf_ch);
5401 if (buf_ch < 0)
5402 buf_ch = *d;
5404 else
5405 buf_ch = *d;
5406 if (buf_ch != pat_ch)
5408 d = dfail;
5409 goto fail;
5411 p += pat_charlen;
5412 d++;
5414 while (--mcnt);
5415 #endif
5416 break;
5419 /* Match any character except possibly a newline or a null. */
5420 case anychar:
5422 int buf_charlen;
5423 re_wchar_t buf_ch;
5425 DEBUG_PRINT ("EXECUTING anychar.\n");
5427 PREFETCH ();
5428 buf_ch = RE_STRING_CHAR_AND_LENGTH (d, buf_charlen,
5429 target_multibyte);
5430 buf_ch = TRANSLATE (buf_ch);
5432 if ((!(bufp->syntax & RE_DOT_NEWLINE)
5433 && buf_ch == '\n')
5434 || ((bufp->syntax & RE_DOT_NOT_NULL)
5435 && buf_ch == '\000'))
5436 goto fail;
5438 DEBUG_PRINT (" Matched `%d'.\n", *d);
5439 d += buf_charlen;
5441 break;
5444 case charset:
5445 case charset_not:
5447 register unsigned int c;
5448 boolean not = (re_opcode_t) *(p - 1) == charset_not;
5449 int len;
5451 /* Start of actual range_table, or end of bitmap if there is no
5452 range table. */
5453 re_char *range_table IF_LINT (= NULL);
5455 /* Nonzero if there is a range table. */
5456 int range_table_exists;
5458 /* Number of ranges of range table. This is not included
5459 in the initial byte-length of the command. */
5460 int count = 0;
5462 /* Whether matching against a unibyte character. */
5463 boolean unibyte_char = false;
5465 DEBUG_PRINT ("EXECUTING charset%s.\n", not ? "_not" : "");
5467 range_table_exists = CHARSET_RANGE_TABLE_EXISTS_P (&p[-1]);
5469 if (range_table_exists)
5471 range_table = CHARSET_RANGE_TABLE (&p[-1]); /* Past the bitmap. */
5472 EXTRACT_NUMBER_AND_INCR (count, range_table);
5475 PREFETCH ();
5476 c = RE_STRING_CHAR_AND_LENGTH (d, len, target_multibyte);
5477 if (target_multibyte)
5479 int c1;
5481 c = TRANSLATE (c);
5482 c1 = RE_CHAR_TO_UNIBYTE (c);
5483 if (c1 >= 0)
5485 unibyte_char = true;
5486 c = c1;
5489 else
5491 int c1 = RE_CHAR_TO_MULTIBYTE (c);
5493 if (! CHAR_BYTE8_P (c1))
5495 c1 = TRANSLATE (c1);
5496 c1 = RE_CHAR_TO_UNIBYTE (c1);
5497 if (c1 >= 0)
5499 unibyte_char = true;
5500 c = c1;
5503 else
5504 unibyte_char = true;
5507 if (unibyte_char && c < (1 << BYTEWIDTH))
5508 { /* Lookup bitmap. */
5509 /* Cast to `unsigned' instead of `unsigned char' in
5510 case the bit list is a full 32 bytes long. */
5511 if (c < (unsigned) (CHARSET_BITMAP_SIZE (&p[-1]) * BYTEWIDTH)
5512 && p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
5513 not = !not;
5515 #ifdef emacs
5516 else if (range_table_exists)
5518 int class_bits = CHARSET_RANGE_TABLE_BITS (&p[-1]);
5520 if ( (class_bits & BIT_LOWER && ISLOWER (c))
5521 | (class_bits & BIT_MULTIBYTE)
5522 | (class_bits & BIT_PUNCT && ISPUNCT (c))
5523 | (class_bits & BIT_SPACE && ISSPACE (c))
5524 | (class_bits & BIT_UPPER && ISUPPER (c))
5525 | (class_bits & BIT_WORD && ISWORD (c))
5526 | (class_bits & BIT_ALPHA && ISALPHA (c))
5527 | (class_bits & BIT_ALNUM && ISALNUM (c))
5528 | (class_bits & BIT_GRAPH && ISGRAPH (c))
5529 | (class_bits & BIT_PRINT && ISPRINT (c)))
5530 not = !not;
5531 else
5532 CHARSET_LOOKUP_RANGE_TABLE_RAW (not, c, range_table, count);
5534 #endif /* emacs */
5536 if (range_table_exists)
5537 p = CHARSET_RANGE_TABLE_END (range_table, count);
5538 else
5539 p += CHARSET_BITMAP_SIZE (&p[-1]) + 1;
5541 if (!not) goto fail;
5543 d += len;
5545 break;
5548 /* The beginning of a group is represented by start_memory.
5549 The argument is the register number. The text
5550 matched within the group is recorded (in the internal
5551 registers data structure) under the register number. */
5552 case start_memory:
5553 DEBUG_PRINT ("EXECUTING start_memory %d:\n", *p);
5555 /* In case we need to undo this operation (via backtracking). */
5556 PUSH_FAILURE_REG (*p);
5558 regstart[*p] = d;
5559 regend[*p] = NULL; /* probably unnecessary. -sm */
5560 DEBUG_PRINT (" regstart: %td\n", POINTER_TO_OFFSET (regstart[*p]));
5562 /* Move past the register number and inner group count. */
5563 p += 1;
5564 break;
5567 /* The stop_memory opcode represents the end of a group. Its
5568 argument is the same as start_memory's: the register number. */
5569 case stop_memory:
5570 DEBUG_PRINT ("EXECUTING stop_memory %d:\n", *p);
5572 assert (!REG_UNSET (regstart[*p]));
5573 /* Strictly speaking, there should be code such as:
5575 assert (REG_UNSET (regend[*p]));
5576 PUSH_FAILURE_REGSTOP ((unsigned int)*p);
5578 But the only info to be pushed is regend[*p] and it is known to
5579 be UNSET, so there really isn't anything to push.
5580 Not pushing anything, on the other hand deprives us from the
5581 guarantee that regend[*p] is UNSET since undoing this operation
5582 will not reset its value properly. This is not important since
5583 the value will only be read on the next start_memory or at
5584 the very end and both events can only happen if this stop_memory
5585 is *not* undone. */
5587 regend[*p] = d;
5588 DEBUG_PRINT (" regend: %td\n", POINTER_TO_OFFSET (regend[*p]));
5590 /* Move past the register number and the inner group count. */
5591 p += 1;
5592 break;
5595 /* \<digit> has been turned into a `duplicate' command which is
5596 followed by the numeric value of <digit> as the register number. */
5597 case duplicate:
5599 register re_char *d2, *dend2;
5600 int regno = *p++; /* Get which register to match against. */
5601 DEBUG_PRINT ("EXECUTING duplicate %d.\n", regno);
5603 /* Can't back reference a group which we've never matched. */
5604 if (REG_UNSET (regstart[regno]) || REG_UNSET (regend[regno]))
5605 goto fail;
5607 /* Where in input to try to start matching. */
5608 d2 = regstart[regno];
5610 /* Remember the start point to rollback upon failure. */
5611 dfail = d;
5613 /* Where to stop matching; if both the place to start and
5614 the place to stop matching are in the same string, then
5615 set to the place to stop, otherwise, for now have to use
5616 the end of the first string. */
5618 dend2 = ((FIRST_STRING_P (regstart[regno])
5619 == FIRST_STRING_P (regend[regno]))
5620 ? regend[regno] : end_match_1);
5621 for (;;)
5623 ptrdiff_t dcnt;
5625 /* If necessary, advance to next segment in register
5626 contents. */
5627 while (d2 == dend2)
5629 if (dend2 == end_match_2) break;
5630 if (dend2 == regend[regno]) break;
5632 /* End of string1 => advance to string2. */
5633 d2 = string2;
5634 dend2 = regend[regno];
5636 /* At end of register contents => success */
5637 if (d2 == dend2) break;
5639 /* If necessary, advance to next segment in data. */
5640 PREFETCH ();
5642 /* How many characters left in this segment to match. */
5643 dcnt = dend - d;
5645 /* Want how many consecutive characters we can match in
5646 one shot, so, if necessary, adjust the count. */
5647 if (dcnt > dend2 - d2)
5648 dcnt = dend2 - d2;
5650 /* Compare that many; failure if mismatch, else move
5651 past them. */
5652 if (RE_TRANSLATE_P (translate)
5653 ? bcmp_translate (d, d2, dcnt, translate, target_multibyte)
5654 : memcmp (d, d2, dcnt))
5656 d = dfail;
5657 goto fail;
5659 d += dcnt, d2 += dcnt;
5662 break;
5665 /* begline matches the empty string at the beginning of the string
5666 (unless `not_bol' is set in `bufp'), and after newlines. */
5667 case begline:
5668 DEBUG_PRINT ("EXECUTING begline.\n");
5670 if (AT_STRINGS_BEG (d))
5672 if (!bufp->not_bol) break;
5674 else
5676 unsigned c;
5677 GET_CHAR_BEFORE_2 (c, d, string1, end1, string2, end2);
5678 if (c == '\n')
5679 break;
5681 /* In all other cases, we fail. */
5682 goto fail;
5685 /* endline is the dual of begline. */
5686 case endline:
5687 DEBUG_PRINT ("EXECUTING endline.\n");
5689 if (AT_STRINGS_END (d))
5691 if (!bufp->not_eol) break;
5693 else
5695 PREFETCH_NOLIMIT ();
5696 if (*d == '\n')
5697 break;
5699 goto fail;
5702 /* Match at the very beginning of the data. */
5703 case begbuf:
5704 DEBUG_PRINT ("EXECUTING begbuf.\n");
5705 if (AT_STRINGS_BEG (d))
5706 break;
5707 goto fail;
5710 /* Match at the very end of the data. */
5711 case endbuf:
5712 DEBUG_PRINT ("EXECUTING endbuf.\n");
5713 if (AT_STRINGS_END (d))
5714 break;
5715 goto fail;
5718 /* on_failure_keep_string_jump is used to optimize `.*\n'. It
5719 pushes NULL as the value for the string on the stack. Then
5720 `POP_FAILURE_POINT' will keep the current value for the
5721 string, instead of restoring it. To see why, consider
5722 matching `foo\nbar' against `.*\n'. The .* matches the foo;
5723 then the . fails against the \n. But the next thing we want
5724 to do is match the \n against the \n; if we restored the
5725 string value, we would be back at the foo.
5727 Because this is used only in specific cases, we don't need to
5728 check all the things that `on_failure_jump' does, to make
5729 sure the right things get saved on the stack. Hence we don't
5730 share its code. The only reason to push anything on the
5731 stack at all is that otherwise we would have to change
5732 `anychar's code to do something besides goto fail in this
5733 case; that seems worse than this. */
5734 case on_failure_keep_string_jump:
5735 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5736 DEBUG_PRINT ("EXECUTING on_failure_keep_string_jump %d (to %p):\n",
5737 mcnt, p + mcnt);
5739 PUSH_FAILURE_POINT (p - 3, NULL);
5740 break;
5742 /* A nasty loop is introduced by the non-greedy *? and +?.
5743 With such loops, the stack only ever contains one failure point
5744 at a time, so that a plain on_failure_jump_loop kind of
5745 cycle detection cannot work. Worse yet, such a detection
5746 can not only fail to detect a cycle, but it can also wrongly
5747 detect a cycle (between different instantiations of the same
5748 loop).
5749 So the method used for those nasty loops is a little different:
5750 We use a special cycle-detection-stack-frame which is pushed
5751 when the on_failure_jump_nastyloop failure-point is *popped*.
5752 This special frame thus marks the beginning of one iteration
5753 through the loop and we can hence easily check right here
5754 whether something matched between the beginning and the end of
5755 the loop. */
5756 case on_failure_jump_nastyloop:
5757 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5758 DEBUG_PRINT ("EXECUTING on_failure_jump_nastyloop %d (to %p):\n",
5759 mcnt, p + mcnt);
5761 assert ((re_opcode_t)p[-4] == no_op);
5763 int cycle = 0;
5764 CHECK_INFINITE_LOOP (p - 4, d);
5765 if (!cycle)
5766 /* If there's a cycle, just continue without pushing
5767 this failure point. The failure point is the "try again"
5768 option, which shouldn't be tried.
5769 We want (x?)*?y\1z to match both xxyz and xxyxz. */
5770 PUSH_FAILURE_POINT (p - 3, d);
5772 break;
5774 /* Simple loop detecting on_failure_jump: just check on the
5775 failure stack if the same spot was already hit earlier. */
5776 case on_failure_jump_loop:
5777 on_failure:
5778 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5779 DEBUG_PRINT ("EXECUTING on_failure_jump_loop %d (to %p):\n",
5780 mcnt, p + mcnt);
5782 int cycle = 0;
5783 CHECK_INFINITE_LOOP (p - 3, d);
5784 if (cycle)
5785 /* If there's a cycle, get out of the loop, as if the matching
5786 had failed. We used to just `goto fail' here, but that was
5787 aborting the search a bit too early: we want to keep the
5788 empty-loop-match and keep matching after the loop.
5789 We want (x?)*y\1z to match both xxyz and xxyxz. */
5790 p += mcnt;
5791 else
5792 PUSH_FAILURE_POINT (p - 3, d);
5794 break;
5797 /* Uses of on_failure_jump:
5799 Each alternative starts with an on_failure_jump that points
5800 to the beginning of the next alternative. Each alternative
5801 except the last ends with a jump that in effect jumps past
5802 the rest of the alternatives. (They really jump to the
5803 ending jump of the following alternative, because tensioning
5804 these jumps is a hassle.)
5806 Repeats start with an on_failure_jump that points past both
5807 the repetition text and either the following jump or
5808 pop_failure_jump back to this on_failure_jump. */
5809 case on_failure_jump:
5810 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5811 DEBUG_PRINT ("EXECUTING on_failure_jump %d (to %p):\n",
5812 mcnt, p + mcnt);
5814 PUSH_FAILURE_POINT (p -3, d);
5815 break;
5817 /* This operation is used for greedy *.
5818 Compare the beginning of the repeat with what in the
5819 pattern follows its end. If we can establish that there
5820 is nothing that they would both match, i.e., that we
5821 would have to backtrack because of (as in, e.g., `a*a')
5822 then we can use a non-backtracking loop based on
5823 on_failure_keep_string_jump instead of on_failure_jump. */
5824 case on_failure_jump_smart:
5825 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5826 DEBUG_PRINT ("EXECUTING on_failure_jump_smart %d (to %p).\n",
5827 mcnt, p + mcnt);
5829 re_char *p1 = p; /* Next operation. */
5830 /* Here, we discard `const', making re_match non-reentrant. */
5831 unsigned char *p2 = (unsigned char*) p + mcnt; /* Jump dest. */
5832 unsigned char *p3 = (unsigned char*) p - 3; /* opcode location. */
5834 p -= 3; /* Reset so that we will re-execute the
5835 instruction once it's been changed. */
5837 EXTRACT_NUMBER (mcnt, p2 - 2);
5839 /* Ensure this is a indeed the trivial kind of loop
5840 we are expecting. */
5841 assert (skip_one_char (p1) == p2 - 3);
5842 assert ((re_opcode_t) p2[-3] == jump && p2 + mcnt == p);
5843 DEBUG_STATEMENT (debug += 2);
5844 if (mutually_exclusive_p (bufp, p1, p2))
5846 /* Use a fast `on_failure_keep_string_jump' loop. */
5847 DEBUG_PRINT (" smart exclusive => fast loop.\n");
5848 *p3 = (unsigned char) on_failure_keep_string_jump;
5849 STORE_NUMBER (p2 - 2, mcnt + 3);
5851 else
5853 /* Default to a safe `on_failure_jump' loop. */
5854 DEBUG_PRINT (" smart default => slow loop.\n");
5855 *p3 = (unsigned char) on_failure_jump;
5857 DEBUG_STATEMENT (debug -= 2);
5859 break;
5861 /* Unconditionally jump (without popping any failure points). */
5862 case jump:
5863 unconditional_jump:
5864 IMMEDIATE_QUIT_CHECK;
5865 EXTRACT_NUMBER_AND_INCR (mcnt, p); /* Get the amount to jump. */
5866 DEBUG_PRINT ("EXECUTING jump %d ", mcnt);
5867 p += mcnt; /* Do the jump. */
5868 DEBUG_PRINT ("(to %p).\n", p);
5869 break;
5872 /* Have to succeed matching what follows at least n times.
5873 After that, handle like `on_failure_jump'. */
5874 case succeed_n:
5875 /* Signedness doesn't matter since we only compare MCNT to 0. */
5876 EXTRACT_NUMBER (mcnt, p + 2);
5877 DEBUG_PRINT ("EXECUTING succeed_n %d.\n", mcnt);
5879 /* Originally, mcnt is how many times we HAVE to succeed. */
5880 if (mcnt != 0)
5882 /* Here, we discard `const', making re_match non-reentrant. */
5883 unsigned char *p2 = (unsigned char*) p + 2; /* counter loc. */
5884 mcnt--;
5885 p += 4;
5886 PUSH_NUMBER (p2, mcnt);
5888 else
5889 /* The two bytes encoding mcnt == 0 are two no_op opcodes. */
5890 goto on_failure;
5891 break;
5893 case jump_n:
5894 /* Signedness doesn't matter since we only compare MCNT to 0. */
5895 EXTRACT_NUMBER (mcnt, p + 2);
5896 DEBUG_PRINT ("EXECUTING jump_n %d.\n", mcnt);
5898 /* Originally, this is how many times we CAN jump. */
5899 if (mcnt != 0)
5901 /* Here, we discard `const', making re_match non-reentrant. */
5902 unsigned char *p2 = (unsigned char*) p + 2; /* counter loc. */
5903 mcnt--;
5904 PUSH_NUMBER (p2, mcnt);
5905 goto unconditional_jump;
5907 /* If don't have to jump any more, skip over the rest of command. */
5908 else
5909 p += 4;
5910 break;
5912 case set_number_at:
5914 unsigned char *p2; /* Location of the counter. */
5915 DEBUG_PRINT ("EXECUTING set_number_at.\n");
5917 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5918 /* Here, we discard `const', making re_match non-reentrant. */
5919 p2 = (unsigned char*) p + mcnt;
5920 /* Signedness doesn't matter since we only copy MCNT's bits. */
5921 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5922 DEBUG_PRINT (" Setting %p to %d.\n", p2, mcnt);
5923 PUSH_NUMBER (p2, mcnt);
5924 break;
5927 case wordbound:
5928 case notwordbound:
5930 boolean not = (re_opcode_t) *(p - 1) == notwordbound;
5931 DEBUG_PRINT ("EXECUTING %swordbound.\n", not ? "not" : "");
5933 /* We SUCCEED (or FAIL) in one of the following cases: */
5935 /* Case 1: D is at the beginning or the end of string. */
5936 if (AT_STRINGS_BEG (d) || AT_STRINGS_END (d))
5937 not = !not;
5938 else
5940 /* C1 is the character before D, S1 is the syntax of C1, C2
5941 is the character at D, and S2 is the syntax of C2. */
5942 re_wchar_t c1, c2;
5943 int s1, s2;
5944 int dummy;
5945 #ifdef emacs
5946 ssize_t offset = PTR_TO_OFFSET (d - 1);
5947 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5948 UPDATE_SYNTAX_TABLE (charpos);
5949 #endif
5950 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
5951 s1 = SYNTAX (c1);
5952 #ifdef emacs
5953 UPDATE_SYNTAX_TABLE_FORWARD (charpos + 1);
5954 #endif
5955 PREFETCH_NOLIMIT ();
5956 GET_CHAR_AFTER (c2, d, dummy);
5957 s2 = SYNTAX (c2);
5959 if (/* Case 2: Only one of S1 and S2 is Sword. */
5960 ((s1 == Sword) != (s2 == Sword))
5961 /* Case 3: Both of S1 and S2 are Sword, and macro
5962 WORD_BOUNDARY_P (C1, C2) returns nonzero. */
5963 || ((s1 == Sword) && WORD_BOUNDARY_P (c1, c2)))
5964 not = !not;
5966 if (not)
5967 break;
5968 else
5969 goto fail;
5972 case wordbeg:
5973 DEBUG_PRINT ("EXECUTING wordbeg.\n");
5975 /* We FAIL in one of the following cases: */
5977 /* Case 1: D is at the end of string. */
5978 if (AT_STRINGS_END (d))
5979 goto fail;
5980 else
5982 /* C1 is the character before D, S1 is the syntax of C1, C2
5983 is the character at D, and S2 is the syntax of C2. */
5984 re_wchar_t c1, c2;
5985 int s1, s2;
5986 int dummy;
5987 #ifdef emacs
5988 ssize_t offset = PTR_TO_OFFSET (d);
5989 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
5990 UPDATE_SYNTAX_TABLE (charpos);
5991 #endif
5992 PREFETCH ();
5993 GET_CHAR_AFTER (c2, d, dummy);
5994 s2 = SYNTAX (c2);
5996 /* Case 2: S2 is not Sword. */
5997 if (s2 != Sword)
5998 goto fail;
6000 /* Case 3: D is not at the beginning of string ... */
6001 if (!AT_STRINGS_BEG (d))
6003 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
6004 #ifdef emacs
6005 UPDATE_SYNTAX_TABLE_BACKWARD (charpos - 1);
6006 #endif
6007 s1 = SYNTAX (c1);
6009 /* ... and S1 is Sword, and WORD_BOUNDARY_P (C1, C2)
6010 returns 0. */
6011 if ((s1 == Sword) && !WORD_BOUNDARY_P (c1, c2))
6012 goto fail;
6015 break;
6017 case wordend:
6018 DEBUG_PRINT ("EXECUTING wordend.\n");
6020 /* We FAIL in one of the following cases: */
6022 /* Case 1: D is at the beginning of string. */
6023 if (AT_STRINGS_BEG (d))
6024 goto fail;
6025 else
6027 /* C1 is the character before D, S1 is the syntax of C1, C2
6028 is the character at D, and S2 is the syntax of C2. */
6029 re_wchar_t c1, c2;
6030 int s1, s2;
6031 int dummy;
6032 #ifdef emacs
6033 ssize_t offset = PTR_TO_OFFSET (d) - 1;
6034 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
6035 UPDATE_SYNTAX_TABLE (charpos);
6036 #endif
6037 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
6038 s1 = SYNTAX (c1);
6040 /* Case 2: S1 is not Sword. */
6041 if (s1 != Sword)
6042 goto fail;
6044 /* Case 3: D is not at the end of string ... */
6045 if (!AT_STRINGS_END (d))
6047 PREFETCH_NOLIMIT ();
6048 GET_CHAR_AFTER (c2, d, dummy);
6049 #ifdef emacs
6050 UPDATE_SYNTAX_TABLE_FORWARD (charpos);
6051 #endif
6052 s2 = SYNTAX (c2);
6054 /* ... and S2 is Sword, and WORD_BOUNDARY_P (C1, C2)
6055 returns 0. */
6056 if ((s2 == Sword) && !WORD_BOUNDARY_P (c1, c2))
6057 goto fail;
6060 break;
6062 case symbeg:
6063 DEBUG_PRINT ("EXECUTING symbeg.\n");
6065 /* We FAIL in one of the following cases: */
6067 /* Case 1: D is at the end of string. */
6068 if (AT_STRINGS_END (d))
6069 goto fail;
6070 else
6072 /* C1 is the character before D, S1 is the syntax of C1, C2
6073 is the character at D, and S2 is the syntax of C2. */
6074 re_wchar_t c1, c2;
6075 int s1, s2;
6076 #ifdef emacs
6077 ssize_t offset = PTR_TO_OFFSET (d);
6078 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
6079 UPDATE_SYNTAX_TABLE (charpos);
6080 #endif
6081 PREFETCH ();
6082 c2 = RE_STRING_CHAR (d, target_multibyte);
6083 s2 = SYNTAX (c2);
6085 /* Case 2: S2 is neither Sword nor Ssymbol. */
6086 if (s2 != Sword && s2 != Ssymbol)
6087 goto fail;
6089 /* Case 3: D is not at the beginning of string ... */
6090 if (!AT_STRINGS_BEG (d))
6092 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
6093 #ifdef emacs
6094 UPDATE_SYNTAX_TABLE_BACKWARD (charpos - 1);
6095 #endif
6096 s1 = SYNTAX (c1);
6098 /* ... and S1 is Sword or Ssymbol. */
6099 if (s1 == Sword || s1 == Ssymbol)
6100 goto fail;
6103 break;
6105 case symend:
6106 DEBUG_PRINT ("EXECUTING symend.\n");
6108 /* We FAIL in one of the following cases: */
6110 /* Case 1: D is at the beginning of string. */
6111 if (AT_STRINGS_BEG (d))
6112 goto fail;
6113 else
6115 /* C1 is the character before D, S1 is the syntax of C1, C2
6116 is the character at D, and S2 is the syntax of C2. */
6117 re_wchar_t c1, c2;
6118 int s1, s2;
6119 #ifdef emacs
6120 ssize_t offset = PTR_TO_OFFSET (d) - 1;
6121 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
6122 UPDATE_SYNTAX_TABLE (charpos);
6123 #endif
6124 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
6125 s1 = SYNTAX (c1);
6127 /* Case 2: S1 is neither Ssymbol nor Sword. */
6128 if (s1 != Sword && s1 != Ssymbol)
6129 goto fail;
6131 /* Case 3: D is not at the end of string ... */
6132 if (!AT_STRINGS_END (d))
6134 PREFETCH_NOLIMIT ();
6135 c2 = RE_STRING_CHAR (d, target_multibyte);
6136 #ifdef emacs
6137 UPDATE_SYNTAX_TABLE_FORWARD (charpos + 1);
6138 #endif
6139 s2 = SYNTAX (c2);
6141 /* ... and S2 is Sword or Ssymbol. */
6142 if (s2 == Sword || s2 == Ssymbol)
6143 goto fail;
6146 break;
6148 case syntaxspec:
6149 case notsyntaxspec:
6151 boolean not = (re_opcode_t) *(p - 1) == notsyntaxspec;
6152 mcnt = *p++;
6153 DEBUG_PRINT ("EXECUTING %ssyntaxspec %d.\n", not ? "not" : "",
6154 mcnt);
6155 PREFETCH ();
6156 #ifdef emacs
6158 ssize_t offset = PTR_TO_OFFSET (d);
6159 ssize_t pos1 = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
6160 UPDATE_SYNTAX_TABLE (pos1);
6162 #endif
6164 int len;
6165 re_wchar_t c;
6167 GET_CHAR_AFTER (c, d, len);
6168 if ((SYNTAX (c) != (enum syntaxcode) mcnt) ^ not)
6169 goto fail;
6170 d += len;
6173 break;
6175 #ifdef emacs
6176 case before_dot:
6177 DEBUG_PRINT ("EXECUTING before_dot.\n");
6178 if (PTR_BYTE_POS (d) >= PT_BYTE)
6179 goto fail;
6180 break;
6182 case at_dot:
6183 DEBUG_PRINT ("EXECUTING at_dot.\n");
6184 if (PTR_BYTE_POS (d) != PT_BYTE)
6185 goto fail;
6186 break;
6188 case after_dot:
6189 DEBUG_PRINT ("EXECUTING after_dot.\n");
6190 if (PTR_BYTE_POS (d) <= PT_BYTE)
6191 goto fail;
6192 break;
6194 case categoryspec:
6195 case notcategoryspec:
6197 boolean not = (re_opcode_t) *(p - 1) == notcategoryspec;
6198 mcnt = *p++;
6199 DEBUG_PRINT ("EXECUTING %scategoryspec %d.\n",
6200 not ? "not" : "", mcnt);
6201 PREFETCH ();
6204 int len;
6205 re_wchar_t c;
6206 GET_CHAR_AFTER (c, d, len);
6207 if ((!CHAR_HAS_CATEGORY (c, mcnt)) ^ not)
6208 goto fail;
6209 d += len;
6212 break;
6214 #endif /* emacs */
6216 default:
6217 abort ();
6219 continue; /* Successfully executed one pattern command; keep going. */
6222 /* We goto here if a matching operation fails. */
6223 fail:
6224 IMMEDIATE_QUIT_CHECK;
6225 if (!FAIL_STACK_EMPTY ())
6227 re_char *str, *pat;
6228 /* A restart point is known. Restore to that state. */
6229 DEBUG_PRINT ("\nFAIL:\n");
6230 POP_FAILURE_POINT (str, pat);
6231 switch (*pat++)
6233 case on_failure_keep_string_jump:
6234 assert (str == NULL);
6235 goto continue_failure_jump;
6237 case on_failure_jump_nastyloop:
6238 assert ((re_opcode_t)pat[-2] == no_op);
6239 PUSH_FAILURE_POINT (pat - 2, str);
6240 /* Fallthrough */
6242 case on_failure_jump_loop:
6243 case on_failure_jump:
6244 case succeed_n:
6245 d = str;
6246 continue_failure_jump:
6247 EXTRACT_NUMBER_AND_INCR (mcnt, pat);
6248 p = pat + mcnt;
6249 break;
6251 case no_op:
6252 /* A special frame used for nastyloops. */
6253 goto fail;
6255 default:
6256 abort ();
6259 assert (p >= bufp->buffer && p <= pend);
6261 if (d >= string1 && d <= end1)
6262 dend = end_match_1;
6264 else
6265 break; /* Matching at this starting point really fails. */
6266 } /* for (;;) */
6268 if (best_regs_set)
6269 goto restore_best_regs;
6271 FREE_VARIABLES ();
6273 return -1; /* Failure to match. */
6276 /* Subroutine definitions for re_match_2. */
6278 /* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
6279 bytes; nonzero otherwise. */
6281 static int
6282 bcmp_translate (const_re_char *s1, const_re_char *s2, register ssize_t len,
6283 RE_TRANSLATE_TYPE translate, const int target_multibyte)
6285 register re_char *p1 = s1, *p2 = s2;
6286 re_char *p1_end = s1 + len;
6287 re_char *p2_end = s2 + len;
6289 /* FIXME: Checking both p1 and p2 presumes that the two strings might have
6290 different lengths, but relying on a single `len' would break this. -sm */
6291 while (p1 < p1_end && p2 < p2_end)
6293 int p1_charlen, p2_charlen;
6294 re_wchar_t p1_ch, p2_ch;
6296 GET_CHAR_AFTER (p1_ch, p1, p1_charlen);
6297 GET_CHAR_AFTER (p2_ch, p2, p2_charlen);
6299 if (RE_TRANSLATE (translate, p1_ch)
6300 != RE_TRANSLATE (translate, p2_ch))
6301 return 1;
6303 p1 += p1_charlen, p2 += p2_charlen;
6306 if (p1 != p1_end || p2 != p2_end)
6307 return 1;
6309 return 0;
6312 /* Entry points for GNU code. */
6314 /* re_compile_pattern is the GNU regular expression compiler: it
6315 compiles PATTERN (of length SIZE) and puts the result in BUFP.
6316 Returns 0 if the pattern was valid, otherwise an error string.
6318 Assumes the `allocated' (and perhaps `buffer') and `translate' fields
6319 are set in BUFP on entry.
6321 We call regex_compile to do the actual compilation. */
6323 const char *
6324 re_compile_pattern (const char *pattern, size_t length,
6325 struct re_pattern_buffer *bufp)
6327 reg_errcode_t ret;
6329 /* GNU code is written to assume at least RE_NREGS registers will be set
6330 (and at least one extra will be -1). */
6331 bufp->regs_allocated = REGS_UNALLOCATED;
6333 /* And GNU code determines whether or not to get register information
6334 by passing null for the REGS argument to re_match, etc., not by
6335 setting no_sub. */
6336 bufp->no_sub = 0;
6338 ret = regex_compile ((re_char*) pattern, length, re_syntax_options, bufp);
6340 if (!ret)
6341 return NULL;
6342 return gettext (re_error_msgid[(int) ret]);
6344 WEAK_ALIAS (__re_compile_pattern, re_compile_pattern)
6346 /* Entry points compatible with 4.2 BSD regex library. We don't define
6347 them unless specifically requested. */
6349 #if defined _REGEX_RE_COMP || defined _LIBC
6351 /* BSD has one and only one pattern buffer. */
6352 static struct re_pattern_buffer re_comp_buf;
6354 char *
6355 # ifdef _LIBC
6356 /* Make these definitions weak in libc, so POSIX programs can redefine
6357 these names if they don't use our functions, and still use
6358 regcomp/regexec below without link errors. */
6359 weak_function
6360 # endif
6361 re_comp (const char *s)
6363 reg_errcode_t ret;
6365 if (!s)
6367 if (!re_comp_buf.buffer)
6368 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6369 return (char *) gettext ("No previous regular expression");
6370 return 0;
6373 if (!re_comp_buf.buffer)
6375 re_comp_buf.buffer = malloc (200);
6376 if (re_comp_buf.buffer == NULL)
6377 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6378 return (char *) gettext (re_error_msgid[(int) REG_ESPACE]);
6379 re_comp_buf.allocated = 200;
6381 re_comp_buf.fastmap = malloc (1 << BYTEWIDTH);
6382 if (re_comp_buf.fastmap == NULL)
6383 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6384 return (char *) gettext (re_error_msgid[(int) REG_ESPACE]);
6387 /* Since `re_exec' always passes NULL for the `regs' argument, we
6388 don't need to initialize the pattern buffer fields which affect it. */
6390 ret = regex_compile (s, strlen (s), re_syntax_options, &re_comp_buf);
6392 if (!ret)
6393 return NULL;
6395 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
6396 return (char *) gettext (re_error_msgid[(int) ret]);
6401 # ifdef _LIBC
6402 weak_function
6403 # endif
6404 re_exec (const char *s)
6406 const size_t len = strlen (s);
6407 return re_search (&re_comp_buf, s, len, 0, len, 0) >= 0;
6409 #endif /* _REGEX_RE_COMP */
6411 /* POSIX.2 functions. Don't define these for Emacs. */
6413 #ifndef emacs
6415 /* regcomp takes a regular expression as a string and compiles it.
6417 PREG is a regex_t *. We do not expect any fields to be initialized,
6418 since POSIX says we shouldn't. Thus, we set
6420 `buffer' to the compiled pattern;
6421 `used' to the length of the compiled pattern;
6422 `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
6423 REG_EXTENDED bit in CFLAGS is set; otherwise, to
6424 RE_SYNTAX_POSIX_BASIC;
6425 `fastmap' to an allocated space for the fastmap;
6426 `fastmap_accurate' to zero;
6427 `re_nsub' to the number of subexpressions in PATTERN.
6429 PATTERN is the address of the pattern string.
6431 CFLAGS is a series of bits which affect compilation.
6433 If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
6434 use POSIX basic syntax.
6436 If REG_NEWLINE is set, then . and [^...] don't match newline.
6437 Also, regexec will try a match beginning after every newline.
6439 If REG_ICASE is set, then we considers upper- and lowercase
6440 versions of letters to be equivalent when matching.
6442 If REG_NOSUB is set, then when PREG is passed to regexec, that
6443 routine will report only success or failure, and nothing about the
6444 registers.
6446 It returns 0 if it succeeds, nonzero if it doesn't. (See regex.h for
6447 the return codes and their meanings.) */
6449 reg_errcode_t
6450 regcomp (regex_t *_Restrict_ preg, const char *_Restrict_ pattern,
6451 int cflags)
6453 reg_errcode_t ret;
6454 reg_syntax_t syntax
6455 = (cflags & REG_EXTENDED) ?
6456 RE_SYNTAX_POSIX_EXTENDED : RE_SYNTAX_POSIX_BASIC;
6458 /* regex_compile will allocate the space for the compiled pattern. */
6459 preg->buffer = 0;
6460 preg->allocated = 0;
6461 preg->used = 0;
6463 /* Try to allocate space for the fastmap. */
6464 preg->fastmap = malloc (1 << BYTEWIDTH);
6466 if (cflags & REG_ICASE)
6468 unsigned i;
6470 preg->translate = malloc (CHAR_SET_SIZE * sizeof *preg->translate);
6471 if (preg->translate == NULL)
6472 return (int) REG_ESPACE;
6474 /* Map uppercase characters to corresponding lowercase ones. */
6475 for (i = 0; i < CHAR_SET_SIZE; i++)
6476 preg->translate[i] = ISUPPER (i) ? TOLOWER (i) : i;
6478 else
6479 preg->translate = NULL;
6481 /* If REG_NEWLINE is set, newlines are treated differently. */
6482 if (cflags & REG_NEWLINE)
6483 { /* REG_NEWLINE implies neither . nor [^...] match newline. */
6484 syntax &= ~RE_DOT_NEWLINE;
6485 syntax |= RE_HAT_LISTS_NOT_NEWLINE;
6487 else
6488 syntax |= RE_NO_NEWLINE_ANCHOR;
6490 preg->no_sub = !!(cflags & REG_NOSUB);
6492 /* POSIX says a null character in the pattern terminates it, so we
6493 can use strlen here in compiling the pattern. */
6494 ret = regex_compile ((re_char*) pattern, strlen (pattern), syntax, preg);
6496 /* POSIX doesn't distinguish between an unmatched open-group and an
6497 unmatched close-group: both are REG_EPAREN. */
6498 if (ret == REG_ERPAREN)
6499 ret = REG_EPAREN;
6501 if (ret == REG_NOERROR && preg->fastmap)
6502 { /* Compute the fastmap now, since regexec cannot modify the pattern
6503 buffer. */
6504 re_compile_fastmap (preg);
6505 if (preg->can_be_null)
6506 { /* The fastmap can't be used anyway. */
6507 free (preg->fastmap);
6508 preg->fastmap = NULL;
6511 return ret;
6513 WEAK_ALIAS (__regcomp, regcomp)
6516 /* regexec searches for a given pattern, specified by PREG, in the
6517 string STRING.
6519 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
6520 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
6521 least NMATCH elements, and we set them to the offsets of the
6522 corresponding matched substrings.
6524 EFLAGS specifies `execution flags' which affect matching: if
6525 REG_NOTBOL is set, then ^ does not match at the beginning of the
6526 string; if REG_NOTEOL is set, then $ does not match at the end.
6528 We return 0 if we find a match and REG_NOMATCH if not. */
6530 reg_errcode_t
6531 regexec (const regex_t *_Restrict_ preg, const char *_Restrict_ string,
6532 size_t nmatch, regmatch_t pmatch[_Restrict_arr_], int eflags)
6534 regoff_t ret;
6535 struct re_registers regs;
6536 regex_t private_preg;
6537 size_t len = strlen (string);
6538 boolean want_reg_info = !preg->no_sub && nmatch > 0 && pmatch;
6540 private_preg = *preg;
6542 private_preg.not_bol = !!(eflags & REG_NOTBOL);
6543 private_preg.not_eol = !!(eflags & REG_NOTEOL);
6545 /* The user has told us exactly how many registers to return
6546 information about, via `nmatch'. We have to pass that on to the
6547 matching routines. */
6548 private_preg.regs_allocated = REGS_FIXED;
6550 if (want_reg_info)
6552 regs.num_regs = nmatch;
6553 regs.start = TALLOC (nmatch * 2, regoff_t);
6554 if (regs.start == NULL)
6555 return REG_NOMATCH;
6556 regs.end = regs.start + nmatch;
6559 /* Instead of using not_eol to implement REG_NOTEOL, we could simply
6560 pass (&private_preg, string, len + 1, 0, len, ...) pretending the string
6561 was a little bit longer but still only matching the real part.
6562 This works because the `endline' will check for a '\n' and will find a
6563 '\0', correctly deciding that this is not the end of a line.
6564 But it doesn't work out so nicely for REG_NOTBOL, since we don't have
6565 a convenient '\0' there. For all we know, the string could be preceded
6566 by '\n' which would throw things off. */
6568 /* Perform the searching operation. */
6569 ret = re_search (&private_preg, string, len,
6570 /* start: */ 0, /* range: */ len,
6571 want_reg_info ? &regs : 0);
6573 /* Copy the register information to the POSIX structure. */
6574 if (want_reg_info)
6576 if (ret >= 0)
6578 unsigned r;
6580 for (r = 0; r < nmatch; r++)
6582 pmatch[r].rm_so = regs.start[r];
6583 pmatch[r].rm_eo = regs.end[r];
6587 /* If we needed the temporary register info, free the space now. */
6588 free (regs.start);
6591 /* We want zero return to mean success, unlike `re_search'. */
6592 return ret >= 0 ? REG_NOERROR : REG_NOMATCH;
6594 WEAK_ALIAS (__regexec, regexec)
6597 /* Returns a message corresponding to an error code, ERR_CODE, returned
6598 from either regcomp or regexec. We don't use PREG here.
6600 ERR_CODE was previously called ERRCODE, but that name causes an
6601 error with msvc8 compiler. */
6603 size_t
6604 regerror (int err_code, const regex_t *preg, char *errbuf, size_t errbuf_size)
6606 const char *msg;
6607 size_t msg_size;
6609 if (err_code < 0
6610 || err_code >= (sizeof (re_error_msgid) / sizeof (re_error_msgid[0])))
6611 /* Only error codes returned by the rest of the code should be passed
6612 to this routine. If we are given anything else, or if other regex
6613 code generates an invalid error code, then the program has a bug.
6614 Dump core so we can fix it. */
6615 abort ();
6617 msg = gettext (re_error_msgid[err_code]);
6619 msg_size = strlen (msg) + 1; /* Includes the null. */
6621 if (errbuf_size != 0)
6623 if (msg_size > errbuf_size)
6625 memcpy (errbuf, msg, errbuf_size - 1);
6626 errbuf[errbuf_size - 1] = 0;
6628 else
6629 strcpy (errbuf, msg);
6632 return msg_size;
6634 WEAK_ALIAS (__regerror, regerror)
6637 /* Free dynamically allocated space used by PREG. */
6639 void
6640 regfree (regex_t *preg)
6642 free (preg->buffer);
6643 preg->buffer = NULL;
6645 preg->allocated = 0;
6646 preg->used = 0;
6648 free (preg->fastmap);
6649 preg->fastmap = NULL;
6650 preg->fastmap_accurate = 0;
6652 free (preg->translate);
6653 preg->translate = NULL;
6655 WEAK_ALIAS (__regfree, regfree)
6657 #endif /* not emacs */