1 /* Extended regular expression matching and search library,
3 * (Implements POSIX draft P1003.2/D11.2, except for some of the
4 * internationalization features.)
6 * Copyright (C) 1993, 1994, 1995, 1996, 1997 Free Software Foundation, Inc.
8 * This file is part of the GNU C Library. Its master source is NOT part of
9 * the C library, however. The master source lives in /gd/gnu/lib.
11 * The GNU C Library is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU Library General Public License as
13 * published by the Free Software Foundation; either version 2 of the
14 * License, or (at your option) any later version.
16 * The GNU C Library is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 * Library General Public License for more details.
21 * You should have received a copy of the GNU Library General Public
22 * License along with the GNU C Library; see the file COPYING.LIB. If not,
23 * write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
24 * Boston, MA 02111-1307, USA.
30 * Use _regex.h instead of regex.h. tlr, 1999-01-06
31 * Make REGEX_MALLOC depend on HAVE_ALLOCA &c.
33 * Don't switch on regex debugging when debugging mutt.
37 /* The following doesn't mix too well with autoconfiguring
38 * the use of alloca. So let's disable it for AIX.
43 /* AIX requires this to be the first thing in the file. */
44 # if defined (_AIX) && !defined (REGEX_MALLOC)
59 #if (defined(HAVE_ALLOCA_H) && !defined(_AIX))
63 #if (!defined(HAVE_ALLOCA) || defined(_AIX))
67 #if defined(STDC_HEADERS) && !defined(emacs)
70 /* We need this for `regex.h', and perhaps for the Emacs include files. */
71 #include <sys/types.h>
74 /* For platform which support the ISO C amendement 1 functionality we
75 support user defined character classes. */
76 #if defined _LIBC || (defined HAVE_WCTYPE_H && defined HAVE_WCHAR_H)
81 /* This is for other GNU distributions with internationalized messages. */
82 #if HAVE_LIBINTL_H || defined (_LIBC)
85 # define gettext(msgid) (msgid)
89 /* This define is so xgettext can find the internationalizable
91 #define gettext_noop(String) String
94 /* The `emacs' switch turns on certain matching commands
95 that make sense only in Emacs. */
102 #else /* not emacs */
104 /* If we are not linking with Emacs proper,
105 we can't use the relocating allocator
106 even if config.h says that we can. */
109 #if defined (STDC_HEADERS) || defined (_LIBC)
112 char *malloc (); /* __MEM_CHECKED__ */
113 char *realloc (); /* __MEM_CHECKED__ */
116 /* When used in Emacs's lib-src, we need to get bzero and bcopy somehow.
117 If nothing else has been done, use the method below. */
118 #ifdef INHIBIT_STRING_HEADER
119 #if !(defined (HAVE_BZERO) && defined (HAVE_BCOPY))
120 #if !defined (bzero) && !defined (bcopy)
121 #undef INHIBIT_STRING_HEADER
126 /* This is the normal way of making sure we have a bcopy and a bzero.
127 This is used in most programs--a few other programs avoid this
128 by defining INHIBIT_STRING_HEADER. */
129 #ifndef INHIBIT_STRING_HEADER
130 #if defined (HAVE_STRING_H) || defined (STDC_HEADERS) || defined (_LIBC)
133 #define bcmp(s1, s2, n) memcmp ((s1), (s2), (n))
136 #define bcopy(s, d, n) memcpy ((d), (s), (n))
139 #define bzero(s, n) memset ((s), 0, (n))
146 /* Define the syntax stuff for \<, \>, etc. */
148 /* This must be nonzero for the wordchar and notwordchar pattern
149 commands in re_match_2. */
154 #ifdef SWITCH_ENUM_BUG
155 #define SWITCH_ENUM_CAST(x) ((int)(x))
157 #define SWITCH_ENUM_CAST(x) (x)
162 extern char *re_syntax_table;
164 #else /* not SYNTAX_TABLE */
166 /* How many characters in the character set. */
167 #define CHAR_SET_SIZE 256
169 static char re_syntax_table[CHAR_SET_SIZE];
172 1, MUTT_ALPHA, MUTT_BLANK, MUTT_CNTRL, MUTT_DIGIT, MUTT_GRAPH,
173 MUTT_LOWER, MUTT_PRINT, MUTT_PUNCT, MUTT_SPACE, MUTT_UPPER, MUTT_XDIGIT,
177 static int ctype (const char *name)
179 if (0 == strcmp (name, "alnum"))
181 if (0 == strcmp (name, "alpha"))
183 if (0 == strcmp (name, "blank"))
185 if (0 == strcmp (name, "cntrl"))
187 if (0 == strcmp (name, "digit"))
189 if (0 == strcmp (name, "graph"))
191 if (0 == strcmp (name, "lower"))
193 if (0 == strcmp (name, "print"))
195 if (0 == strcmp (name, "punct"))
197 if (0 == strcmp (name, "space"))
199 if (0 == strcmp (name, "upper"))
201 if (0 == strcmp (name, "xdigit"))
207 static void init_syntax_once ()
215 bzero (re_syntax_table, sizeof re_syntax_table);
217 for (c = 'a'; c <= 'z'; c++)
218 re_syntax_table[c] = Sword;
220 for (c = 'A'; c <= 'Z'; c++)
221 re_syntax_table[c] = Sword;
223 for (c = '0'; c <= '9'; c++)
224 re_syntax_table[c] = Sword;
226 re_syntax_table['_'] = Sword;
231 #endif /* not SYNTAX_TABLE */
233 #define SYNTAX(c) re_syntax_table[c]
235 #endif /* not emacs */
237 /* Get the interface, including the syntax bits. */
239 /* Changed to fit into mutt - tlr, 1999-01-06 */
243 /* isalpha etc. are used for the character classes. */
246 /* Jim Meyering writes:
248 "... Some ctype macros are valid only for character codes that
249 isascii says are ASCII (SGI's IRIX-4.0.5 is one such system --when
250 using /bin/cc or gcc but without giving an ansi option). So, all
251 ctype uses should be through macros like ISPRINT... If
252 STDC_HEADERS is defined, then autoconf has verified that the ctype
253 macros don't need to be guarded with references to isascii. ...
254 Defining isascii to 1 should let any compiler worth its salt
255 eliminate the && through constant folding." */
257 #if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII))
260 #define ISASCII(c) isascii(c)
264 #define ISBLANK(c) (ISASCII (c) && isblank (c))
266 #define ISBLANK(c) ((c) == ' ' || (c) == '\t')
269 #define ISGRAPH(c) (ISASCII (c) && isgraph (c))
271 #define ISGRAPH(c) (ISASCII (c) && isprint (c) && !isspace (c))
274 #define ISPRINT(c) (ISASCII (c) && isprint (c))
275 #define ISDIGIT(c) (ISASCII (c) && isdigit (c))
276 #define ISALNUM(c) (ISASCII (c) && isalnum (c))
277 #define ISALPHA(c) (ISASCII (c) && isalpha (c))
278 #define ISCNTRL(c) (ISASCII (c) && iscntrl (c))
279 #define ISLOWER(c) (ISASCII (c) && islower (c))
280 #define ISPUNCT(c) (ISASCII (c) && ispunct (c))
281 #define ISSPACE(c) (ISASCII (c) && isspace (c))
282 #define ISUPPER(c) (ISASCII (c) && isupper (c))
283 #define ISXDIGIT(c) (ISASCII (c) && isxdigit (c))
286 #define NULL (void *)0
289 /* We remove any previous definition of `SIGN_EXTEND_CHAR',
290 since ours (we hope) works properly with all combinations of
291 machines, compilers, `char' and `unsigned char' argument types.
292 (Per Bothner suggested the basic approach.) */
293 #undef SIGN_EXTEND_CHAR
295 #define SIGN_EXTEND_CHAR(c) ((signed char) (c))
296 #else /* not __STDC__ */
297 /* As in Harbison and Steele. */
298 #define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128)
301 /* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we
302 use `alloca' instead of `malloc'. This is because using malloc in
303 re_search* or re_match* could cause memory leaks when C-g is used in
304 Emacs; also, malloc is slower and causes storage fragmentation. On
305 the other hand, malloc is more portable, and easier to debug.
307 Because we sometimes use alloca, some routines have to be macros,
308 not functions -- `alloca'-allocated space disappears at the end of the
309 function it is called in. */
313 #define REGEX_ALLOCATE malloc
314 #define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
315 #define REGEX_FREE free
317 #else /* not REGEX_MALLOC */
319 /* Emacs already defines alloca, sometimes. */
322 /* Make alloca work the best possible way. */
324 #define alloca __builtin_alloca
325 #else /* not __GNUC__ */
328 #else /* not __GNUC__ or HAVE_ALLOCA_H */
329 #if 0 /* It is a bad idea to declare alloca. We always cast the result. */
330 #ifndef _AIX /* Already did AIX, up at the top. */
332 #endif /* not _AIX */
334 #endif /* not HAVE_ALLOCA_H */
335 #endif /* not __GNUC__ */
337 #endif /* not alloca */
339 #define REGEX_ALLOCATE alloca
341 /* Assumes a `char *destination' variable. */
342 #define REGEX_REALLOCATE(source, osize, nsize) \
343 (destination = (char *) alloca (nsize), \
344 bcopy (source, destination, osize), \
347 /* No need to do anything to free, after alloca. */
348 #define REGEX_FREE(arg) ((void)0) /* Do nothing! But inhibit gcc warning. */
350 #endif /* not REGEX_MALLOC */
352 /* Define how to allocate the failure stack. */
354 #if defined (REL_ALLOC) && defined (REGEX_MALLOC)
356 #define REGEX_ALLOCATE_STACK(size) \
357 r_alloc (&failure_stack_ptr, (size))
358 #define REGEX_REALLOCATE_STACK(source, osize, nsize) \
359 r_re_alloc (&failure_stack_ptr, (nsize))
360 #define REGEX_FREE_STACK(ptr) \
361 r_alloc_free (&failure_stack_ptr)
363 #else /* not using relocating allocator */
367 #define REGEX_ALLOCATE_STACK malloc
368 #define REGEX_REALLOCATE_STACK(source, osize, nsize) realloc (source, nsize)
369 #define REGEX_FREE_STACK free
371 #else /* not REGEX_MALLOC */
373 #define REGEX_ALLOCATE_STACK alloca
375 #define REGEX_REALLOCATE_STACK(source, osize, nsize) \
376 REGEX_REALLOCATE (source, osize, nsize)
377 /* No need to explicitly free anything. */
378 #define REGEX_FREE_STACK(arg)
380 #endif /* not REGEX_MALLOC */
381 #endif /* not using relocating allocator */
384 /* True if `size1' is non-NULL and PTR is pointing anywhere inside
385 `string1' or just past its end. This works if PTR is NULL, which is
387 #define FIRST_STRING_P(ptr) \
388 (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
390 /* (Re)Allocate N items of type T using malloc, or fail. */
391 #define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
392 #define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
393 #define RETALLOC_IF(addr, n, t) \
394 if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
395 #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
397 #define BYTEWIDTH 8 /* In bits. */
399 #define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
403 #define MAX(a, b) ((a) > (b) ? (a) : (b))
404 #define MIN(a, b) ((a) < (b) ? (a) : (b))
406 typedef char boolean;
411 static int re_match_2_internal ();
413 /* These are the command codes that appear in compiled regular
414 expressions. Some opcodes are followed by argument bytes. A
415 command code can specify any interpretation whatsoever for its
416 arguments. Zero bytes may appear in the compiled regular expression. */
421 /* Succeed right away--no more backtracking. */
424 /* Followed by one byte giving n, then by n literal bytes. */
427 /* Matches any (more or less) character. */
430 /* Matches any one char belonging to specified set. First
431 following byte is number of bitmap bytes. Then come bytes
432 for a bitmap saying which chars are in. Bits in each byte
433 are ordered low-bit-first. A character is in the set if its
434 bit is 1. A character too large to have a bit in the map is
435 automatically not in the set. */
438 /* Same parameters as charset, but match any character that is
439 not one of those specified. */
442 /* Start remembering the text that is matched, for storing in a
443 register. Followed by one byte with the register number, in
444 the range 0 to one less than the pattern buffer's re_nsub
445 field. Then followed by one byte with the number of groups
446 inner to this one. (This last has to be part of the
447 start_memory only because we need it in the on_failure_jump
451 /* Stop remembering the text that is matched and store it in a
452 memory register. Followed by one byte with the register
453 number, in the range 0 to one less than `re_nsub' in the
454 pattern buffer, and one byte with the number of inner groups,
455 just like `start_memory'. (We need the number of inner
456 groups here because we don't have any easy way of finding the
457 corresponding start_memory when we're at a stop_memory.) */
460 /* Match a duplicate of something remembered. Followed by one
461 byte containing the register number. */
464 /* Fail unless at beginning of line. */
467 /* Fail unless at end of line. */
470 /* Succeeds if at beginning of buffer (if emacs) or at beginning
471 of string to be matched (if not). */
474 /* Analogously, for end of buffer/string. */
477 /* Followed by two byte relative address to which to jump. */
480 /* Same as jump, but marks the end of an alternative. */
483 /* Followed by two-byte relative address of place to resume at
484 in case of failure. */
487 /* Like on_failure_jump, but pushes a placeholder instead of the
488 current string position when executed. */
489 on_failure_keep_string_jump,
491 /* Throw away latest failure point and then jump to following
492 two-byte relative address. */
495 /* Change to pop_failure_jump if know won't have to backtrack to
496 match; otherwise change to jump. This is used to jump
497 back to the beginning of a repeat. If what follows this jump
498 clearly won't match what the repeat does, such that we can be
499 sure that there is no use backtracking out of repetitions
500 already matched, then we change it to a pop_failure_jump.
501 Followed by two-byte address. */
504 /* Jump to following two-byte address, and push a dummy failure
505 point. This failure point will be thrown away if an attempt
506 is made to use it for a failure. A `+' construct makes this
507 before the first repeat. Also used as an intermediary kind
508 of jump when compiling an alternative. */
511 /* Push a dummy failure point and continue. Used at the end of
515 /* Followed by two-byte relative address and two-byte number n.
516 After matching N times, jump to the address upon failure. */
519 /* Followed by two-byte relative address, and two-byte number n.
520 Jump to the address N times, then fail. */
523 /* Set the following two-byte relative address to the
524 subsequent two-byte number. The address *includes* the two
528 wordchar, /* Matches any word-constituent character. */
529 notwordchar, /* Matches any char that is not a word-constituent. */
531 wordbeg, /* Succeeds if at word beginning. */
532 wordend, /* Succeeds if at word end. */
534 wordbound, /* Succeeds if at a word boundary. */
535 notwordbound /* Succeeds if not at a word boundary. */
537 , before_dot, /* Succeeds if before point. */
538 at_dot, /* Succeeds if at point. */
539 after_dot, /* Succeeds if after point. */
541 /* Matches any character whose syntax is specified. Followed by
542 a byte which contains a syntax code, e.g., Sword. */
545 /* Matches any character whose syntax is not that specified. */
550 /* Common operations on the compiled pattern. */
552 /* Store NUMBER in two contiguous bytes starting at DESTINATION. */
554 #define STORE_NUMBER(destination, number) \
556 (destination)[0] = (number) & 0377; \
557 (destination)[1] = (number) >> 8; \
560 /* Same as STORE_NUMBER, except increment DESTINATION to
561 the byte after where the number is stored. Therefore, DESTINATION
562 must be an lvalue. */
564 #define STORE_NUMBER_AND_INCR(destination, number) \
566 STORE_NUMBER (destination, number); \
567 (destination) += 2; \
570 /* Put into DESTINATION a number stored in two contiguous bytes starting
573 #define EXTRACT_NUMBER(destination, source) \
575 (destination) = *(source) & 0377; \
576 (destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8; \
580 static void extract_number _RE_ARGS ((int *dest, unsigned char *source));
581 static void extract_number (dest, source)
583 unsigned char *source;
585 int temp = SIGN_EXTEND_CHAR (*(source + 1));
587 *dest = *source & 0377;
591 #ifndef EXTRACT_MACROS /* To debug the macros. */
592 #undef EXTRACT_NUMBER
593 #define EXTRACT_NUMBER(dest, src) extract_number (&dest, src)
594 #endif /* not EXTRACT_MACROS */
598 /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
599 SOURCE must be an lvalue. */
601 #define EXTRACT_NUMBER_AND_INCR(destination, source) \
603 EXTRACT_NUMBER (destination, source); \
608 static void extract_number_and_incr _RE_ARGS ((int *destination,
609 unsigned char **source));
610 static void extract_number_and_incr (destination, source)
612 unsigned char **source;
614 extract_number (destination, *source);
618 #ifndef EXTRACT_MACROS
619 #undef EXTRACT_NUMBER_AND_INCR
620 #define EXTRACT_NUMBER_AND_INCR(dest, src) \
621 extract_number_and_incr (&dest, &src)
622 #endif /* not EXTRACT_MACROS */
626 /* If DEBUG is defined, Regex prints many voluminous messages about what
627 it is doing (if the variable `debug' is nonzero). If linked with the
628 main program in `iregex.c', you can enter patterns and strings
629 interactively. And if linked with the main program in `main.c' and
630 the other test files, you can run the already-written tests. */
634 /* We use standard I/O for debugging. */
637 /* It is useful to test things that ``must'' be true when debugging. */
640 static int debug = 0;
642 #define DEBUG_STATEMENT(e) e
643 #define DEBUG_PRINT1(x) if (debug) printf (x)
644 #define DEBUG_PRINT2(x1, x2) if (debug) printf (x1, x2)
645 #define DEBUG_PRINT3(x1, x2, x3) if (debug) printf (x1, x2, x3)
646 #define DEBUG_PRINT4(x1, x2, x3, x4) if (debug) printf (x1, x2, x3, x4)
647 #define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) \
648 if (debug) print_partial_compiled_pattern (s, e)
649 #define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) \
650 if (debug) print_double_string (w, s1, sz1, s2, sz2)
653 /* Print the fastmap in human-readable form. */
655 void print_fastmap (fastmap)
658 unsigned was_a_range = 0;
661 while (i < (1 << BYTEWIDTH)) {
665 while (i < (1 << BYTEWIDTH) && fastmap[i]) {
679 /* Print a compiled pattern string in human-readable form, starting at
680 the START pointer into it and ending just before the pointer END. */
682 void print_partial_compiled_pattern (start, end)
683 unsigned char *start;
688 unsigned char *p = start;
689 unsigned char *pend = end;
696 /* Loop over pattern commands. */
698 printf ("%d:\t", p - start);
700 switch ((re_opcode_t) * p++) {
707 printf ("/exactn/%d", mcnt);
717 printf ("/start_memory/%d/%d", mcnt, *p++);
722 printf ("/stop_memory/%d/%d", mcnt, *p++);
726 printf ("/duplicate/%d", *p++);
736 register int c, last = -100;
737 register int in_range = 0;
739 printf ("/charset [%s",
740 (re_opcode_t) * (p - 1) == charset_not ? "^" : "");
742 assert (p + *p < pend);
744 for (c = 0; c < 256; c++)
745 if (c / 8 < *p && (p[1 + (c / 8)] & (1 << (c % 8)))) {
746 /* Are we starting a range? */
747 if (last + 1 == c && !in_range) {
751 /* Have we broken a range? */
752 else if (last + 1 != c && in_range) {
780 case on_failure_jump:
781 extract_number_and_incr (&mcnt, &p);
782 printf ("/on_failure_jump to %d", p + mcnt - start);
785 case on_failure_keep_string_jump:
786 extract_number_and_incr (&mcnt, &p);
787 printf ("/on_failure_keep_string_jump to %d", p + mcnt - start);
790 case dummy_failure_jump:
791 extract_number_and_incr (&mcnt, &p);
792 printf ("/dummy_failure_jump to %d", p + mcnt - start);
795 case push_dummy_failure:
796 printf ("/push_dummy_failure");
800 extract_number_and_incr (&mcnt, &p);
801 printf ("/maybe_pop_jump to %d", p + mcnt - start);
804 case pop_failure_jump:
805 extract_number_and_incr (&mcnt, &p);
806 printf ("/pop_failure_jump to %d", p + mcnt - start);
810 extract_number_and_incr (&mcnt, &p);
811 printf ("/jump_past_alt to %d", p + mcnt - start);
815 extract_number_and_incr (&mcnt, &p);
816 printf ("/jump to %d", p + mcnt - start);
820 extract_number_and_incr (&mcnt, &p);
822 extract_number_and_incr (&mcnt2, &p);
823 printf ("/succeed_n to %d, %d times", p1 - start, mcnt2);
827 extract_number_and_incr (&mcnt, &p);
829 extract_number_and_incr (&mcnt2, &p);
830 printf ("/jump_n to %d, %d times", p1 - start, mcnt2);
834 extract_number_and_incr (&mcnt, &p);
836 extract_number_and_incr (&mcnt2, &p);
837 printf ("/set_number_at location %d to %d", p1 - start, mcnt2);
841 printf ("/wordbound");
845 printf ("/notwordbound");
857 printf ("/before_dot");
865 printf ("/after_dot");
869 printf ("/syntaxspec");
871 printf ("/%d", mcnt);
875 printf ("/notsyntaxspec");
877 printf ("/%d", mcnt);
882 printf ("/wordchar");
886 printf ("/notwordchar");
898 printf ("?%d", *(p - 1));
904 printf ("%d:\tend of pattern.\n", p - start);
908 void print_compiled_pattern (bufp)
909 struct re_pattern_buffer *bufp;
911 unsigned char *buffer = bufp->buffer;
913 print_partial_compiled_pattern (buffer, buffer + bufp->used);
914 printf ("%ld bytes used/%ld bytes allocated.\n",
915 bufp->used, bufp->allocated);
917 if (bufp->fastmap_accurate && bufp->fastmap) {
918 printf ("fastmap: ");
919 print_fastmap (bufp->fastmap);
922 printf ("re_nsub: %d\t", bufp->re_nsub);
923 printf ("regs_alloc: %d\t", bufp->regs_allocated);
924 printf ("can_be_null: %d\t", bufp->can_be_null);
925 printf ("newline_anchor: %d\n", bufp->newline_anchor);
926 printf ("no_sub: %d\t", bufp->no_sub);
927 printf ("not_bol: %d\t", bufp->not_bol);
928 printf ("not_eol: %d\t", bufp->not_eol);
929 printf ("syntax: %lx\n", bufp->syntax);
930 /* Perhaps we should print the translate table? */
934 void print_double_string (where, string1, size1, string2, size2)
946 if (FIRST_STRING_P (where)) {
947 for (this_char = where - string1; this_char < size1; this_char++)
948 putchar (string1[this_char]);
953 for (this_char = where - string2; this_char < size2; this_char++)
954 putchar (string2[this_char]);
964 #else /* not DEBUG */
969 #define DEBUG_STATEMENT(e)
970 #define DEBUG_PRINT1(x)
971 #define DEBUG_PRINT2(x1, x2)
972 #define DEBUG_PRINT3(x1, x2, x3)
973 #define DEBUG_PRINT4(x1, x2, x3, x4)
974 #define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
975 #define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
977 #endif /* not DEBUG */
979 /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
980 also be assigned to arbitrarily: each pattern buffer stores its own
981 syntax, so it can be changed between regex compilations. */
982 /* This has no initializer because initialized variables in Emacs
983 become read-only after dumping. */
984 reg_syntax_t re_syntax_options;
987 /* Specify the precise syntax of regexps for compilation. This provides
988 for compatibility for various utilities which historically have
989 different, incompatible syntaxes.
991 The argument SYNTAX is a bit mask comprised of the various bits
992 defined in regex.h. We return the old syntax. */
994 reg_syntax_t re_set_syntax (syntax)
997 reg_syntax_t ret = re_syntax_options;
999 re_syntax_options = syntax;
1001 if (syntax & RE_DEBUG)
1003 else if (debug) /* was on but now is not */
1009 /* This table gives an error message for each of the error codes listed
1010 in regex.h. Obviously the order here has to be same as there.
1011 POSIX doesn't require that we do anything for REG_NOERROR,
1012 but why not be nice? */
1014 static const char *re_error_msgid[] = {
1015 gettext_noop ("Success"), /* REG_NOERROR */
1016 gettext_noop ("No match"), /* REG_NOMATCH */
1017 gettext_noop ("Invalid regular expression"), /* REG_BADPAT */
1018 gettext_noop ("Invalid collation character"), /* REG_ECOLLATE */
1019 gettext_noop ("Invalid character class name"), /* REG_ECTYPE */
1020 gettext_noop ("Trailing backslash"), /* REG_EESCAPE */
1021 gettext_noop ("Invalid back reference"), /* REG_ESUBREG */
1022 gettext_noop ("Unmatched [ or [^"), /* REG_EBRACK */
1023 gettext_noop ("Unmatched ( or \\("), /* REG_EPAREN */
1024 gettext_noop ("Unmatched \\{"), /* REG_EBRACE */
1025 gettext_noop ("Invalid content of \\{\\}"), /* REG_BADBR */
1026 gettext_noop ("Invalid range end"), /* REG_ERANGE */
1027 gettext_noop ("Memory exhausted"), /* REG_ESPACE */
1028 gettext_noop ("Invalid preceding regular expression"), /* REG_BADRPT */
1029 gettext_noop ("Premature end of regular expression"), /* REG_EEND */
1030 gettext_noop ("Regular expression too big"), /* REG_ESIZE */
1031 gettext_noop ("Unmatched ) or \\)"), /* REG_ERPAREN */
1034 /* Avoiding alloca during matching, to placate r_alloc. */
1036 /* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
1037 searching and matching functions should not call alloca. On some
1038 systems, alloca is implemented in terms of malloc, and if we're
1039 using the relocating allocator routines, then malloc could cause a
1040 relocation, which might (if the strings being searched are in the
1041 ralloc heap) shift the data out from underneath the regexp
1044 Here's another reason to avoid allocation: Emacs
1045 processes input from X in a signal handler; processing X input may
1046 call malloc; if input arrives while a matching routine is calling
1047 malloc, then we're scrod. But Emacs can't just block input while
1048 calling matching routines; then we don't notice interrupts when
1049 they come in. So, Emacs blocks input around all regexp calls
1050 except the matching calls, which it leaves unprotected, in the
1051 faith that they will not malloc. */
1053 /* Normally, this is fine. */
1054 #define MATCH_MAY_ALLOCATE
1056 /* When using GNU C, we are not REALLY using the C alloca, no matter
1057 what config.h may say. So don't take precautions for it. */
1062 /* The match routines may not allocate if (1) they would do it with malloc
1063 and (2) it's not safe for them to use malloc.
1064 Note that if REL_ALLOC is defined, matching would not use malloc for the
1065 failure stack, but we would still use it for the register vectors;
1066 so REL_ALLOC should not affect this. */
1067 #if (defined (C_ALLOCA) || defined (REGEX_MALLOC)) && defined (emacs)
1068 #undef MATCH_MAY_ALLOCATE
1072 /* Failure stack declarations and macros; both re_compile_fastmap and
1073 re_match_2 use a failure stack. These have to be macros because of
1074 REGEX_ALLOCATE_STACK. */
1077 /* Number of failure points for which to initially allocate space
1078 when matching. If this number is exceeded, we allocate more
1079 space, so it is not a hard limit. */
1080 #ifndef INIT_FAILURE_ALLOC
1081 #define INIT_FAILURE_ALLOC 5
1084 /* Roughly the maximum number of failure points on the stack. Would be
1085 exactly that if always used MAX_FAILURE_ITEMS items each time we failed.
1086 This is a variable only so users of regex can assign to it; we never
1087 change it ourselves. */
1091 #if defined (MATCH_MAY_ALLOCATE)
1092 /* 4400 was enough to cause a crash on Alpha OSF/1,
1093 whose default stack limit is 2mb. */
1094 long int re_max_failures = 4000;
1096 long int re_max_failures = 2000;
1099 union fail_stack_elt {
1100 unsigned char *pointer;
1104 typedef union fail_stack_elt fail_stack_elt_t;
1107 fail_stack_elt_t *stack;
1108 unsigned long int size;
1109 unsigned long int avail; /* Offset of next open position. */
1112 #else /* not INT_IS_16BIT */
1114 #if defined (MATCH_MAY_ALLOCATE)
1115 /* 4400 was enough to cause a crash on Alpha OSF/1,
1116 whose default stack limit is 2mb. */
1117 int re_max_failures = 20000;
1119 int re_max_failures = 2000;
1122 union fail_stack_elt {
1123 unsigned char *pointer;
1127 typedef union fail_stack_elt fail_stack_elt_t;
1130 fail_stack_elt_t *stack;
1132 unsigned avail; /* Offset of next open position. */
1135 #endif /* INT_IS_16BIT */
1137 #define FAIL_STACK_EMPTY() (fail_stack.avail == 0)
1138 #define FAIL_STACK_PTR_EMPTY() (fail_stack_ptr->avail == 0)
1139 #define FAIL_STACK_FULL() (fail_stack.avail == fail_stack.size)
1142 /* Define macros to initialize and free the failure stack.
1143 Do `return -2' if the alloc fails. */
1145 #ifdef MATCH_MAY_ALLOCATE
1146 #define INIT_FAIL_STACK() \
1148 fail_stack.stack = (fail_stack_elt_t *) \
1149 REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * sizeof (fail_stack_elt_t)); \
1151 if (fail_stack.stack == NULL) \
1154 fail_stack.size = INIT_FAILURE_ALLOC; \
1155 fail_stack.avail = 0; \
1158 #define RESET_FAIL_STACK() REGEX_FREE_STACK (fail_stack.stack)
1160 #define INIT_FAIL_STACK() \
1162 fail_stack.avail = 0; \
1165 #define RESET_FAIL_STACK()
1169 /* Double the size of FAIL_STACK, up to approximately `re_max_failures' items.
1171 Return 1 if succeeds, and 0 if either ran out of memory
1172 allocating space for it or it was already too large.
1174 REGEX_REALLOCATE_STACK requires `destination' be declared. */
1176 #define DOUBLE_FAIL_STACK(fail_stack) \
1177 ((fail_stack).size > (unsigned) (re_max_failures * MAX_FAILURE_ITEMS) \
1179 : ((fail_stack).stack = (fail_stack_elt_t *) \
1180 REGEX_REALLOCATE_STACK ((fail_stack).stack, \
1181 (fail_stack).size * sizeof (fail_stack_elt_t), \
1182 ((fail_stack).size << 1) * sizeof (fail_stack_elt_t)), \
1184 (fail_stack).stack == NULL \
1186 : ((fail_stack).size <<= 1, \
1190 /* Push pointer POINTER on FAIL_STACK.
1191 Return 1 if was able to do so and 0 if ran out of memory allocating
1193 #define PUSH_PATTERN_OP(POINTER, FAIL_STACK) \
1194 ((FAIL_STACK_FULL () \
1195 && !DOUBLE_FAIL_STACK (FAIL_STACK)) \
1197 : ((FAIL_STACK).stack[(FAIL_STACK).avail++].pointer = POINTER, \
1200 /* Push a pointer value onto the failure stack.
1201 Assumes the variable `fail_stack'. Probably should only
1202 be called from within `PUSH_FAILURE_POINT'. */
1203 #define PUSH_FAILURE_POINTER(item) \
1204 fail_stack.stack[fail_stack.avail++].pointer = (unsigned char *) (item)
1206 /* This pushes an integer-valued item onto the failure stack.
1207 Assumes the variable `fail_stack'. Probably should only
1208 be called from within `PUSH_FAILURE_POINT'. */
1209 #define PUSH_FAILURE_INT(item) \
1210 fail_stack.stack[fail_stack.avail++].integer = (item)
1212 /* Push a fail_stack_elt_t value onto the failure stack.
1213 Assumes the variable `fail_stack'. Probably should only
1214 be called from within `PUSH_FAILURE_POINT'. */
1215 #define PUSH_FAILURE_ELT(item) \
1216 fail_stack.stack[fail_stack.avail++] = (item)
1218 /* These three POP... operations complement the three PUSH... operations.
1219 All assume that `fail_stack' is nonempty. */
1220 #define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
1221 #define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
1222 #define POP_FAILURE_ELT() fail_stack.stack[--fail_stack.avail]
1224 /* Used to omit pushing failure point id's when we're not debugging. */
1226 #define DEBUG_PUSH PUSH_FAILURE_INT
1227 #define DEBUG_POP(item_addr) (item_addr)->integer = POP_FAILURE_INT ()
1229 #define DEBUG_PUSH(item)
1230 #define DEBUG_POP(item_addr)
1234 /* Push the information about the state we will need
1235 if we ever fail back to it.
1237 Requires variables fail_stack, regstart, regend, reg_info, and
1238 num_regs be declared. DOUBLE_FAIL_STACK requires `destination' be
1241 Does `return FAILURE_CODE' if runs out of memory. */
1243 #define PUSH_FAILURE_POINT(pattern_place, string_place, failure_code) \
1245 char *destination; \
1246 /* Must be int, so when we don't save any registers, the arithmetic \
1247 of 0 + -1 isn't done as unsigned. */ \
1248 /* Can't be int, since there is not a shred of a guarantee that int \
1249 is wide enough to hold a value of something to which pointer can \
1253 DEBUG_STATEMENT (failure_id++); \
1254 DEBUG_STATEMENT (nfailure_points_pushed++); \
1255 DEBUG_PRINT2 ("\nPUSH_FAILURE_POINT #%u:\n", failure_id); \
1256 DEBUG_PRINT2 (" Before push, next avail: %d\n", (fail_stack).avail);\
1257 DEBUG_PRINT2 (" size: %d\n", (fail_stack).size);\
1259 DEBUG_PRINT2 (" slots needed: %d\n", NUM_FAILURE_ITEMS); \
1260 DEBUG_PRINT2 (" available: %d\n", REMAINING_AVAIL_SLOTS); \
1262 /* Ensure we have enough space allocated for what we will push. */ \
1263 while (REMAINING_AVAIL_SLOTS < NUM_FAILURE_ITEMS) \
1265 if (!DOUBLE_FAIL_STACK (fail_stack)) \
1266 return failure_code; \
1268 DEBUG_PRINT2 ("\n Doubled stack; size now: %d\n", \
1269 (fail_stack).size); \
1270 DEBUG_PRINT2 (" slots available: %d\n", REMAINING_AVAIL_SLOTS);\
1273 /* Push the info, starting with the registers. */ \
1274 DEBUG_PRINT1 ("\n"); \
1277 for (this_reg = lowest_active_reg; this_reg <= highest_active_reg; \
1280 DEBUG_PRINT2 (" Pushing reg: %d\n", this_reg); \
1281 DEBUG_STATEMENT (num_regs_pushed++); \
1283 DEBUG_PRINT2 (" start: 0x%x\n", regstart[this_reg]); \
1284 PUSH_FAILURE_POINTER (regstart[this_reg]); \
1286 DEBUG_PRINT2 (" end: 0x%x\n", regend[this_reg]); \
1287 PUSH_FAILURE_POINTER (regend[this_reg]); \
1289 DEBUG_PRINT2 (" info: 0x%x\n ", reg_info[this_reg]); \
1290 DEBUG_PRINT2 (" match_null=%d", \
1291 REG_MATCH_NULL_STRING_P (reg_info[this_reg])); \
1292 DEBUG_PRINT2 (" active=%d", IS_ACTIVE (reg_info[this_reg])); \
1293 DEBUG_PRINT2 (" matched_something=%d", \
1294 MATCHED_SOMETHING (reg_info[this_reg])); \
1295 DEBUG_PRINT2 (" ever_matched=%d", \
1296 EVER_MATCHED_SOMETHING (reg_info[this_reg])); \
1297 DEBUG_PRINT1 ("\n"); \
1298 PUSH_FAILURE_ELT (reg_info[this_reg].word); \
1301 DEBUG_PRINT2 (" Pushing low active reg: %d\n", lowest_active_reg);\
1302 PUSH_FAILURE_INT (lowest_active_reg); \
1304 DEBUG_PRINT2 (" Pushing high active reg: %d\n", highest_active_reg);\
1305 PUSH_FAILURE_INT (highest_active_reg); \
1307 DEBUG_PRINT2 (" Pushing pattern 0x%x:\n", pattern_place); \
1308 DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern_place, pend); \
1309 PUSH_FAILURE_POINTER (pattern_place); \
1311 DEBUG_PRINT2 (" Pushing string 0x%x: `", string_place); \
1312 DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2, \
1314 DEBUG_PRINT1 ("'\n"); \
1315 PUSH_FAILURE_POINTER (string_place); \
1317 DEBUG_PRINT2 (" Pushing failure id: %u\n", failure_id); \
1318 DEBUG_PUSH (failure_id); \
1321 /* This is the number of items that are pushed and popped on the stack
1322 for each register. */
1323 #define NUM_REG_ITEMS 3
1325 /* Individual items aside from the registers. */
1327 #define NUM_NONREG_ITEMS 5 /* Includes failure point id. */
1329 #define NUM_NONREG_ITEMS 4
1332 /* We push at most this many items on the stack. */
1333 /* We used to use (num_regs - 1), which is the number of registers
1334 this regexp will save; but that was changed to 5
1335 to avoid stack overflow for a regexp with lots of parens. */
1336 #define MAX_FAILURE_ITEMS (5 * NUM_REG_ITEMS + NUM_NONREG_ITEMS)
1338 /* We actually push this many items. */
1339 #define NUM_FAILURE_ITEMS \
1341 ? 0 : highest_active_reg - lowest_active_reg + 1) \
1345 /* How many items can still be added to the stack without overflowing it. */
1346 #define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
1349 /* Pops what PUSH_FAIL_STACK pushes.
1351 We restore into the parameters, all of which should be lvalues:
1352 STR -- the saved data position.
1353 PAT -- the saved pattern position.
1354 LOW_REG, HIGH_REG -- the highest and lowest active registers.
1355 REGSTART, REGEND -- arrays of string positions.
1356 REG_INFO -- array of information about each subexpression.
1358 Also assumes the variables `fail_stack' and (if debugging), `bufp',
1359 `pend', `string1', `size1', `string2', and `size2'. */
1361 #define POP_FAILURE_POINT(str, pat, low_reg, high_reg, regstart, regend, reg_info)\
1363 DEBUG_STATEMENT (fail_stack_elt_t failure_id;) \
1365 const unsigned char *string_temp; \
1367 assert (!FAIL_STACK_EMPTY ()); \
1369 /* Remove failure points and point to how many regs pushed. */ \
1370 DEBUG_PRINT1 ("POP_FAILURE_POINT:\n"); \
1371 DEBUG_PRINT2 (" Before pop, next avail: %d\n", fail_stack.avail); \
1372 DEBUG_PRINT2 (" size: %d\n", fail_stack.size); \
1374 assert (fail_stack.avail >= NUM_NONREG_ITEMS); \
1376 DEBUG_POP (&failure_id); \
1377 DEBUG_PRINT2 (" Popping failure id: %u\n", failure_id); \
1379 /* If the saved string location is NULL, it came from an \
1380 on_failure_keep_string_jump opcode, and we want to throw away the \
1381 saved NULL, thus retaining our current position in the string. */ \
1382 string_temp = POP_FAILURE_POINTER (); \
1383 if (string_temp != NULL) \
1384 str = (const char *) string_temp; \
1386 DEBUG_PRINT2 (" Popping string 0x%x: `", str); \
1387 DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2); \
1388 DEBUG_PRINT1 ("'\n"); \
1390 pat = (unsigned char *) POP_FAILURE_POINTER (); \
1391 DEBUG_PRINT2 (" Popping pattern 0x%x:\n", pat); \
1392 DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend); \
1394 /* Restore register info. */ \
1395 high_reg = (active_reg_t) POP_FAILURE_INT (); \
1396 DEBUG_PRINT2 (" Popping high active reg: %d\n", high_reg); \
1398 low_reg = (active_reg_t) POP_FAILURE_INT (); \
1399 DEBUG_PRINT2 (" Popping low active reg: %d\n", low_reg); \
1402 for (this_reg = high_reg; this_reg >= low_reg; this_reg--) \
1404 DEBUG_PRINT2 (" Popping reg: %d\n", this_reg); \
1406 reg_info[this_reg].word = POP_FAILURE_ELT (); \
1407 DEBUG_PRINT2 (" info: 0x%x\n", reg_info[this_reg]); \
1409 regend[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1410 DEBUG_PRINT2 (" end: 0x%x\n", regend[this_reg]); \
1412 regstart[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1413 DEBUG_PRINT2 (" start: 0x%x\n", regstart[this_reg]); \
1417 for (this_reg = highest_active_reg; this_reg > high_reg; this_reg--) \
1419 reg_info[this_reg].word.integer = 0; \
1420 regend[this_reg] = 0; \
1421 regstart[this_reg] = 0; \
1423 highest_active_reg = high_reg; \
1426 set_regs_matched_done = 0; \
1427 DEBUG_STATEMENT (nfailure_points_popped++); \
1428 } /* POP_FAILURE_POINT */
1432 /* Structure for per-register (a.k.a. per-group) information.
1433 Other register information, such as the
1434 starting and ending positions (which are addresses), and the list of
1435 inner groups (which is a bits list) are maintained in separate
1438 We are making a (strictly speaking) nonportable assumption here: that
1439 the compiler will pack our bit fields into something that fits into
1440 the type of `word', i.e., is something that fits into one item on the
1444 /* Declarations and macros for re_match_2. */
1447 fail_stack_elt_t word;
1449 /* This field is one if this group can match the empty string,
1450 zero if not. If not yet determined, `MATCH_NULL_UNSET_VALUE'. */
1451 #define MATCH_NULL_UNSET_VALUE 3
1452 unsigned match_null_string_p:2;
1453 unsigned is_active:1;
1454 unsigned matched_something:1;
1455 unsigned ever_matched_something:1;
1457 } register_info_type;
1459 #define REG_MATCH_NULL_STRING_P(R) ((R).bits.match_null_string_p)
1460 #define IS_ACTIVE(R) ((R).bits.is_active)
1461 #define MATCHED_SOMETHING(R) ((R).bits.matched_something)
1462 #define EVER_MATCHED_SOMETHING(R) ((R).bits.ever_matched_something)
1465 /* Call this when have matched a real character; it sets `matched' flags
1466 for the subexpressions which we are currently inside. Also records
1467 that those subexprs have matched. */
1468 #define SET_REGS_MATCHED() \
1471 if (!set_regs_matched_done) \
1474 set_regs_matched_done = 1; \
1475 for (r = lowest_active_reg; r <= highest_active_reg; r++) \
1477 MATCHED_SOMETHING (reg_info[r]) \
1478 = EVER_MATCHED_SOMETHING (reg_info[r]) \
1485 /* Registers are set to a sentinel when they haven't yet matched. */
1486 static char reg_unset_dummy;
1488 #define REG_UNSET_VALUE (®_unset_dummy)
1489 #define REG_UNSET(e) ((e) == REG_UNSET_VALUE)
1491 /* Subroutine declarations and macros for regex_compile. */
1493 static reg_errcode_t regex_compile
1494 _RE_ARGS ((const char *pattern, size_t size, reg_syntax_t syntax,
1495 struct re_pattern_buffer * bufp));
1496 static void store_op1
1497 _RE_ARGS ((re_opcode_t op, unsigned char *loc, int arg));
1498 static void store_op2
1499 _RE_ARGS ((re_opcode_t op, unsigned char *loc, int arg1, int arg2));
1500 static void insert_op1
1501 _RE_ARGS ((re_opcode_t op, unsigned char *loc, int arg, unsigned char *end));
1502 static void insert_op2
1503 _RE_ARGS ((re_opcode_t op, unsigned char *loc, int arg1, int arg2,
1504 unsigned char *end));
1505 static boolean at_begline_loc_p
1506 _RE_ARGS ((const char *pattern, const char *p, reg_syntax_t syntax));
1507 static boolean at_endline_loc_p
1508 _RE_ARGS ((const char *p, const char *pend, reg_syntax_t syntax));
1509 static reg_errcode_t compile_range
1510 _RE_ARGS ((const char **p_ptr, const char *pend, char *translate,
1511 reg_syntax_t syntax, unsigned char *b));
1513 /* Fetch the next character in the uncompiled pattern---translating it
1514 if necessary. Also cast from a signed character in the constant
1515 string passed to us by the user to an unsigned char that we can use
1516 as an array index (in, e.g., `translate'). */
1518 #define PATFETCH(c) \
1519 do {if (p == pend) return REG_EEND; \
1520 c = (unsigned char) *p++; \
1521 if (translate) c = (unsigned char) translate[c]; \
1525 /* Fetch the next character in the uncompiled pattern, with no
1527 #define PATFETCH_RAW(c) \
1528 do {if (p == pend) return REG_EEND; \
1529 c = (unsigned char) *p++; \
1532 /* Go backwards one character in the pattern. */
1533 #define PATUNFETCH p--
1536 /* If `translate' is non-null, return translate[D], else just D. We
1537 cast the subscript to translate because some data is declared as
1538 `char *', to avoid warnings when a string constant is passed. But
1539 when we use a character as a subscript we must make it unsigned. */
1541 #define TRANSLATE(d) \
1542 (translate ? (char) translate[(unsigned char) (d)] : (d))
1546 /* Macros for outputting the compiled pattern into `buffer'. */
1548 /* If the buffer isn't allocated when it comes in, use this. */
1549 #define INIT_BUF_SIZE 32
1551 /* Make sure we have at least N more bytes of space in buffer. */
1552 #define GET_BUFFER_SPACE(n) \
1553 while ((unsigned long) (b - bufp->buffer + (n)) > bufp->allocated) \
1556 /* Make sure we have one more byte of buffer space and then add C to it. */
1557 #define BUF_PUSH(c) \
1559 GET_BUFFER_SPACE (1); \
1560 *b++ = (unsigned char) (c); \
1564 /* Ensure we have two more bytes of buffer space and then append C1 and C2. */
1565 #define BUF_PUSH_2(c1, c2) \
1567 GET_BUFFER_SPACE (2); \
1568 *b++ = (unsigned char) (c1); \
1569 *b++ = (unsigned char) (c2); \
1573 /* As with BUF_PUSH_2, except for three bytes. */
1574 #define BUF_PUSH_3(c1, c2, c3) \
1576 GET_BUFFER_SPACE (3); \
1577 *b++ = (unsigned char) (c1); \
1578 *b++ = (unsigned char) (c2); \
1579 *b++ = (unsigned char) (c3); \
1583 /* Store a jump with opcode OP at LOC to location TO. We store a
1584 relative address offset by the three bytes the jump itself occupies. */
1585 #define STORE_JUMP(op, loc, to) \
1586 store_op1 (op, loc, (int) ((to) - (loc) - 3))
1588 /* Likewise, for a two-argument jump. */
1589 #define STORE_JUMP2(op, loc, to, arg) \
1590 store_op2 (op, loc, (int) ((to) - (loc) - 3), arg)
1592 /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
1593 #define INSERT_JUMP(op, loc, to) \
1594 insert_op1 (op, loc, (int) ((to) - (loc) - 3), b)
1596 /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
1597 #define INSERT_JUMP2(op, loc, to, arg) \
1598 insert_op2 (op, loc, (int) ((to) - (loc) - 3), arg, b)
1601 /* This is not an arbitrary limit: the arguments which represent offsets
1602 into the pattern are two bytes long. So if 2^16 bytes turns out to
1603 be too small, many things would have to change. */
1604 /* Any other compiler which, like MSC, has allocation limit below 2^16
1605 bytes will have to use approach similar to what was done below for
1606 MSC and drop MAX_BUF_SIZE a bit. Otherwise you may end up
1607 reallocating to 0 bytes. Such thing is not going to work too well.
1608 You have been warned!! */
1609 #if defined(_MSC_VER) && !defined(WIN32)
1610 /* Microsoft C 16-bit versions limit malloc to approx 65512 bytes.
1611 The REALLOC define eliminates a flurry of conversion warnings,
1612 but is not required. */
1613 #define MAX_BUF_SIZE 65500L
1614 #define REALLOC(p,s) realloc ((p), (size_t) (s))
1616 #define MAX_BUF_SIZE (1L << 16)
1617 #define REALLOC(p,s) realloc ((p), (s))
1620 /* Extend the buffer by twice its current size via realloc and
1621 reset the pointers that pointed into the old block to point to the
1622 correct places in the new one. If extending the buffer results in it
1623 being larger than MAX_BUF_SIZE, then flag memory exhausted. */
1624 #define EXTEND_BUFFER() \
1626 unsigned char *old_buffer = bufp->buffer; \
1627 if (bufp->allocated == MAX_BUF_SIZE) \
1629 bufp->allocated <<= 1; \
1630 if (bufp->allocated > MAX_BUF_SIZE) \
1631 bufp->allocated = MAX_BUF_SIZE; \
1632 bufp->buffer = (unsigned char *) REALLOC (bufp->buffer, bufp->allocated);\
1633 if (bufp->buffer == NULL) \
1634 return REG_ESPACE; \
1635 /* If the buffer moved, move all the pointers into it. */ \
1636 if (old_buffer != bufp->buffer) \
1638 b = (b - old_buffer) + bufp->buffer; \
1639 begalt = (begalt - old_buffer) + bufp->buffer; \
1640 if (fixup_alt_jump) \
1641 fixup_alt_jump = (fixup_alt_jump - old_buffer) + bufp->buffer;\
1643 laststart = (laststart - old_buffer) + bufp->buffer; \
1644 if (pending_exact) \
1645 pending_exact = (pending_exact - old_buffer) + bufp->buffer; \
1650 /* Since we have one byte reserved for the register number argument to
1651 {start,stop}_memory, the maximum number of groups we can report
1652 things about is what fits in that byte. */
1653 #define MAX_REGNUM 255
1655 /* But patterns can have more than `MAX_REGNUM' registers. We just
1656 ignore the excess. */
1657 typedef unsigned regnum_t;
1660 /* Macros for the compile stack. */
1662 /* Since offsets can go either forwards or backwards, this type needs to
1663 be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
1664 /* int may be not enough when sizeof(int) == 2. */
1665 typedef long pattern_offset_t;
1668 pattern_offset_t begalt_offset;
1669 pattern_offset_t fixup_alt_jump;
1670 pattern_offset_t inner_group_offset;
1671 pattern_offset_t laststart_offset;
1673 } compile_stack_elt_t;
1677 compile_stack_elt_t *stack;
1679 unsigned avail; /* Offset of next open position. */
1680 } compile_stack_type;
1683 #define INIT_COMPILE_STACK_SIZE 32
1685 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
1686 #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
1688 /* The next available element. */
1689 #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
1692 /* Set the bit for character C in a list. */
1693 #define SET_LIST_BIT(c) \
1694 (b[((unsigned char) (c)) / BYTEWIDTH] \
1695 |= 1 << (((unsigned char) c) % BYTEWIDTH))
1698 /* Get the next unsigned number in the uncompiled pattern. */
1699 #define GET_UNSIGNED_NUMBER(num) \
1703 while (ISDIGIT (c)) \
1707 num = num * 10 + c - '0'; \
1715 #if defined _LIBC || (defined HAVE_WCTYPE_H && defined HAVE_WCHAR_H)
1716 /* The GNU C library provides support for user-defined character classes
1717 and the functions from ISO C amendement 1. */
1718 # ifdef CHARCLASS_NAME_MAX
1719 # define CHAR_CLASS_MAX_LENGTH CHARCLASS_NAME_MAX
1721 /* This shouldn't happen but some implementation might still have this
1722 problem. Use a reasonable default value. */
1723 # define CHAR_CLASS_MAX_LENGTH 256
1726 # define IS_CHAR_CLASS(string) wctype (string)
1728 # define CHAR_CLASS_MAX_LENGTH 6 /* Namely, `xdigit'. */
1730 # define IS_CHAR_CLASS(string) \
1731 (STREQ (string, "alpha") || STREQ (string, "upper") \
1732 || STREQ (string, "lower") || STREQ (string, "digit") \
1733 || STREQ (string, "alnum") || STREQ (string, "xdigit") \
1734 || STREQ (string, "space") || STREQ (string, "print") \
1735 || STREQ (string, "punct") || STREQ (string, "graph") \
1736 || STREQ (string, "cntrl") || STREQ (string, "blank"))
1739 #ifndef MATCH_MAY_ALLOCATE
1741 /* If we cannot allocate large objects within re_match_2_internal,
1742 we make the fail stack and register vectors global.
1743 The fail stack, we grow to the maximum size when a regexp
1745 The register vectors, we adjust in size each time we
1746 compile a regexp, according to the number of registers it needs. */
1748 static fail_stack_type fail_stack;
1750 /* Size with which the following vectors are currently allocated.
1751 That is so we can make them bigger as needed,
1752 but never make them smaller. */
1753 static int regs_allocated_size;
1755 static const char **regstart, **regend;
1756 static const char **old_regstart, **old_regend;
1757 static const char **best_regstart, **best_regend;
1758 static register_info_type *reg_info;
1759 static const char **reg_dummy;
1760 static register_info_type *reg_info_dummy;
1762 /* Make the register vectors big enough for NUM_REGS registers,
1763 but don't make them smaller. */
1765 static regex_grow_registers (num_regs)
1768 if (num_regs > regs_allocated_size) {
1769 RETALLOC_IF (regstart, num_regs, const char *);
1770 RETALLOC_IF (regend, num_regs, const char *);
1771 RETALLOC_IF (old_regstart, num_regs, const char *);
1772 RETALLOC_IF (old_regend, num_regs, const char *);
1773 RETALLOC_IF (best_regstart, num_regs, const char *);
1774 RETALLOC_IF (best_regend, num_regs, const char *);
1776 RETALLOC_IF (reg_info, num_regs, register_info_type);
1777 RETALLOC_IF (reg_dummy, num_regs, const char *);
1779 RETALLOC_IF (reg_info_dummy, num_regs, register_info_type);
1781 regs_allocated_size = num_regs;
1785 #endif /* not MATCH_MAY_ALLOCATE */
1787 static boolean group_in_compile_stack _RE_ARGS ((compile_stack_type
1791 /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
1792 Returns one of error codes defined in `regex.h', or zero for success.
1794 Assumes the `allocated' (and perhaps `buffer') and `translate'
1795 fields are set in BUFP on entry.
1797 If it succeeds, results are put in BUFP (if it returns an error, the
1798 contents of BUFP are undefined):
1799 `buffer' is the compiled pattern;
1800 `syntax' is set to SYNTAX;
1801 `used' is set to the length of the compiled pattern;
1802 `fastmap_accurate' is zero;
1803 `re_nsub' is the number of subexpressions in PATTERN;
1804 `not_bol' and `not_eol' are zero;
1806 The `fastmap' and `newline_anchor' fields are neither
1807 examined nor set. */
1809 /* Return, freeing storage we allocated. */
1810 #define FREE_STACK_RETURN(value) \
1811 return (free (compile_stack.stack), value) /* __MEM_CHECKED__ */
1813 #ifndef HAVE_ISCTYPE
1814 static int isctype (char c, int desc)
1840 return ISXDIGIT (c);
1842 return 0; /* false */
1846 static reg_errcode_t regex_compile (pattern, size, syntax, bufp)
1847 const char *pattern;
1849 reg_syntax_t syntax;
1850 struct re_pattern_buffer *bufp;
1852 /* We fetch characters from PATTERN here. Even though PATTERN is
1853 `char *' (i.e., signed), we declare these variables as unsigned, so
1854 they can be reliably used as array indices. */
1855 register unsigned char c, c1;
1857 /* A random temporary spot in PATTERN. */
1860 /* Points to the end of the buffer, where we should append. */
1861 register unsigned char *b;
1863 /* Keeps track of unclosed groups. */
1864 compile_stack_type compile_stack;
1866 /* Points to the current (ending) position in the pattern. */
1867 const char *p = pattern;
1868 const char *pend = pattern + size;
1870 /* How to translate the characters in the pattern. */
1871 RE_TRANSLATE_TYPE translate = bufp->translate;
1873 /* Address of the count-byte of the most recently inserted `exactn'
1874 command. This makes it possible to tell if a new exact-match
1875 character can be added to that command or if the character requires
1876 a new `exactn' command. */
1877 unsigned char *pending_exact = 0;
1879 /* Address of start of the most recently finished expression.
1880 This tells, e.g., postfix * where to find the start of its
1881 operand. Reset at the beginning of groups and alternatives. */
1882 unsigned char *laststart = 0;
1884 /* Address of beginning of regexp, or inside of last group. */
1885 unsigned char *begalt;
1887 /* Place in the uncompiled pattern (i.e., the {) to
1888 which to go back if the interval is invalid. */
1889 const char *beg_interval;
1891 /* Address of the place where a forward jump should go to the end of
1892 the containing expression. Each alternative of an `or' -- except the
1893 last -- ends with a forward jump of this sort. */
1894 unsigned char *fixup_alt_jump = 0;
1896 /* Counts open-groups as they are encountered. Remembered for the
1897 matching close-group on the compile stack, so the same register
1898 number is put in the stop_memory as the start_memory. */
1899 regnum_t regnum = 0;
1902 DEBUG_PRINT1 ("\nCompiling pattern: ");
1904 unsigned debug_count;
1906 for (debug_count = 0; debug_count < size; debug_count++)
1907 putchar (pattern[debug_count]);
1912 /* Initialize the compile stack. */
1913 compile_stack.stack = TALLOC (INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
1914 if (compile_stack.stack == NULL)
1917 compile_stack.size = INIT_COMPILE_STACK_SIZE;
1918 compile_stack.avail = 0;
1920 /* Initialize the pattern buffer. */
1921 bufp->syntax = syntax;
1922 bufp->fastmap_accurate = 0;
1923 bufp->not_bol = bufp->not_eol = 0;
1925 /* Set `used' to zero, so that if we return an error, the pattern
1926 printer (for debugging) will think there's no pattern. We reset it
1930 /* Always count groups, whether or not bufp->no_sub is set. */
1933 #if !defined (emacs) && !defined (SYNTAX_TABLE)
1934 /* Initialize the syntax table. */
1935 init_syntax_once ();
1938 if (bufp->allocated == 0) {
1939 if (bufp->buffer) { /* If zero allocated, but buffer is non-null, try to realloc
1940 enough space. This loses if buffer's address is bogus, but
1941 that is the user's responsibility. */
1942 RETALLOC (bufp->buffer, INIT_BUF_SIZE, unsigned char);
1944 else { /* Caller did not allocate a buffer. Do it for them. */
1945 bufp->buffer = TALLOC (INIT_BUF_SIZE, unsigned char);
1948 FREE_STACK_RETURN (REG_ESPACE);
1950 bufp->allocated = INIT_BUF_SIZE;
1953 begalt = b = bufp->buffer;
1955 /* Loop through the uncompiled pattern until we're at the end. */
1962 if ( /* If at start of pattern, it's an operator. */
1964 /* If context independent, it's an operator. */
1965 || syntax & RE_CONTEXT_INDEP_ANCHORS
1966 /* Otherwise, depends on what's come before. */
1967 || at_begline_loc_p (pattern, p, syntax))
1977 if ( /* If at end of pattern, it's an operator. */
1979 /* If context independent, it's an operator. */
1980 || syntax & RE_CONTEXT_INDEP_ANCHORS
1981 /* Otherwise, depends on what's next. */
1982 || at_endline_loc_p (p, pend, syntax))
1992 if ((syntax & RE_BK_PLUS_QM)
1993 || (syntax & RE_LIMITED_OPS))
1997 /* If there is no previous pattern... */
1999 if (syntax & RE_CONTEXT_INVALID_OPS)
2000 FREE_STACK_RETURN (REG_BADRPT);
2001 else if (!(syntax & RE_CONTEXT_INDEP_OPS))
2006 /* Are we optimizing this jump? */
2007 boolean keep_string_p = false;
2009 /* 1 means zero (many) matches is allowed. */
2010 char zero_times_ok = 0, many_times_ok = 0;
2012 /* If there is a sequence of repetition chars, collapse it
2013 down to just one (the right one). We can't combine
2014 interval operators with these because of, e.g., `a{2}*',
2015 which should only match an even number of `a's. */
2018 zero_times_ok |= c != '+';
2019 many_times_ok |= c != '?';
2027 || (!(syntax & RE_BK_PLUS_QM) && (c == '+' || c == '?')));
2029 else if (syntax & RE_BK_PLUS_QM && c == '\\') {
2031 FREE_STACK_RETURN (REG_EESCAPE);
2034 if (!(c1 == '+' || c1 == '?')) {
2047 /* If we get here, we found another repeat character. */
2050 /* Star, etc. applied to an empty pattern is equivalent
2051 to an empty pattern. */
2055 /* Now we know whether or not zero matches is allowed
2056 and also whether or not two or more matches is allowed. */
2057 if (many_times_ok) { /* More than one repetition is allowed, so put in at the
2058 end a backward relative jump from `b' to before the next
2059 jump we're going to put in below (which jumps from
2060 laststart to after this jump).
2062 But if we are at the `*' in the exact sequence `.*\n',
2063 insert an unconditional jump backwards to the .,
2064 instead of the beginning of the loop. This way we only
2065 push a failure point once, instead of every time
2066 through the loop. */
2067 assert (p - 1 > pattern);
2069 /* Allocate the space for the jump. */
2070 GET_BUFFER_SPACE (3);
2072 /* We know we are not at the first character of the pattern,
2073 because laststart was nonzero. And we've already
2074 incremented `p', by the way, to be the character after
2075 the `*'. Do we have to do something analogous here
2076 for null bytes, because of RE_DOT_NOT_NULL? */
2077 if (TRANSLATE (*(p - 2)) == TRANSLATE ('.')
2079 && p < pend && TRANSLATE (*p) == TRANSLATE ('\n')
2080 && !(syntax & RE_DOT_NEWLINE)) { /* We have .*\n. */
2081 STORE_JUMP (jump, b, laststart);
2082 keep_string_p = true;
2085 /* Anything else. */
2086 STORE_JUMP (maybe_pop_jump, b, laststart - 3);
2088 /* We've added more stuff to the buffer. */
2092 /* On failure, jump from laststart to b + 3, which will be the
2093 end of the buffer after this jump is inserted. */
2094 GET_BUFFER_SPACE (3);
2095 INSERT_JUMP (keep_string_p ? on_failure_keep_string_jump
2096 : on_failure_jump, laststart, b + 3);
2100 if (!zero_times_ok) {
2101 /* At least one repetition is required, so insert a
2102 `dummy_failure_jump' before the initial
2103 `on_failure_jump' instruction of the loop. This
2104 effects a skip over that instruction the first time
2105 we hit that loop. */
2106 GET_BUFFER_SPACE (3);
2107 INSERT_JUMP (dummy_failure_jump, laststart, laststart + 6);
2122 boolean had_char_class = false;
2125 FREE_STACK_RETURN (REG_EBRACK);
2127 /* Ensure that we have enough space to push a charset: the
2128 opcode, the length count, and the bitset; 34 bytes in all. */
2129 GET_BUFFER_SPACE (34);
2133 /* We test `*p == '^' twice, instead of using an if
2134 statement, so we only need one BUF_PUSH. */
2135 BUF_PUSH (*p == '^' ? charset_not : charset);
2139 /* Remember the first position in the bracket expression. */
2142 /* Push the number of bytes in the bitmap. */
2143 BUF_PUSH ((1 << BYTEWIDTH) / BYTEWIDTH);
2145 /* Clear the whole map. */
2146 bzero (b, (1 << BYTEWIDTH) / BYTEWIDTH);
2148 /* charset_not matches newline according to a syntax bit. */
2149 if ((re_opcode_t) b[-2] == charset_not
2150 && (syntax & RE_HAT_LISTS_NOT_NEWLINE))
2151 SET_LIST_BIT ('\n');
2153 /* Read in characters and ranges, setting map bits. */
2156 FREE_STACK_RETURN (REG_EBRACK);
2160 /* \ might escape characters inside [...] and [^...]. */
2161 if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\') {
2163 FREE_STACK_RETURN (REG_EESCAPE);
2170 /* Could be the end of the bracket expression. If it's
2171 not (i.e., when the bracket expression is `[]' so
2172 far), the ']' character bit gets set way below. */
2173 if (c == ']' && p != p1 + 1)
2176 /* Look ahead to see if it's a range when the last thing
2177 was a character class. */
2178 if (had_char_class && c == '-' && *p != ']')
2179 FREE_STACK_RETURN (REG_ERANGE);
2181 /* Look ahead to see if it's a range when the last thing
2182 was a character: if this is a hyphen not at the
2183 beginning or the end of a list, then it's the range
2185 if (c == '-' && !(p - 2 >= pattern && p[-2] == '[')
2186 && !(p - 3 >= pattern && p[-3] == '[' && p[-2] == '^')
2189 = compile_range (&p, pend, translate, syntax, b);
2190 if (ret != REG_NOERROR)
2191 FREE_STACK_RETURN (ret);
2194 else if (p[0] == '-' && p[1] != ']') { /* This handles ranges made up of characters only. */
2197 /* Move past the `-'. */
2200 ret = compile_range (&p, pend, translate, syntax, b);
2201 if (ret != REG_NOERROR)
2202 FREE_STACK_RETURN (ret);
2205 /* See if we're at the beginning of a possible character
2208 else if (syntax & RE_CHAR_CLASSES && c == '[' && *p == ':') { /* Leave room for the null. */
2209 char str[CHAR_CLASS_MAX_LENGTH + 1];
2214 /* If pattern is `[[:'. */
2216 FREE_STACK_RETURN (REG_EBRACK);
2220 if (c == ':' || c == ']' || p == pend
2221 || c1 == CHAR_CLASS_MAX_LENGTH)
2227 /* If isn't a word bracketed by `[:' and:`]':
2228 undo the ending character, the letters, and leave
2229 the leading `:' and `[' (but set bits for them). */
2230 if (c == ':' && *p == ']') {
2231 #if defined _LIBC || (defined HAVE_WCTYPE_H && defined HAVE_WCHAR_H)
2232 boolean is_lower = STREQ (str, "lower");
2233 boolean is_upper = STREQ (str, "upper");
2239 FREE_STACK_RETURN (REG_ECTYPE);
2241 /* Throw away the ] at the end of the character
2246 FREE_STACK_RETURN (REG_EBRACK);
2248 for (ch = 0; ch < 1 << BYTEWIDTH; ++ch) {
2249 if (isctype (ch, wt))
2252 if (translate && (is_upper || is_lower)
2253 && (ISUPPER (ch) || ISLOWER (ch)))
2257 had_char_class = true;
2260 boolean is_alnum = STREQ (str, "alnum");
2261 boolean is_alpha = STREQ (str, "alpha");
2262 boolean is_blank = STREQ (str, "blank");
2263 boolean is_cntrl = STREQ (str, "cntrl");
2264 boolean is_digit = STREQ (str, "digit");
2265 boolean is_graph = STREQ (str, "graph");
2266 boolean is_lower = STREQ (str, "lower");
2267 boolean is_print = STREQ (str, "print");
2268 boolean is_punct = STREQ (str, "punct");
2269 boolean is_space = STREQ (str, "space");
2270 boolean is_upper = STREQ (str, "upper");
2271 boolean is_xdigit = STREQ (str, "xdigit");
2273 if (!IS_CHAR_CLASS (str))
2274 FREE_STACK_RETURN (REG_ECTYPE);
2276 /* Throw away the ] at the end of the character
2281 FREE_STACK_RETURN (REG_EBRACK);
2283 for (ch = 0; ch < 1 << BYTEWIDTH; ch++) {
2284 /* This was split into 3 if's to
2285 avoid an arbitrary limit in some compiler. */
2286 if ((is_alnum && ISALNUM (ch))
2287 || (is_alpha && ISALPHA (ch))
2288 || (is_blank && ISBLANK (ch))
2289 || (is_cntrl && ISCNTRL (ch)))
2291 if ((is_digit && ISDIGIT (ch))
2292 || (is_graph && ISGRAPH (ch))
2293 || (is_lower && ISLOWER (ch))
2294 || (is_print && ISPRINT (ch)))
2296 if ((is_punct && ISPUNCT (ch))
2297 || (is_space && ISSPACE (ch))
2298 || (is_upper && ISUPPER (ch))
2299 || (is_xdigit && ISXDIGIT (ch)))
2301 if (translate && (is_upper || is_lower)
2302 && (ISUPPER (ch) || ISLOWER (ch)))
2305 had_char_class = true;
2306 #endif /* libc || wctype.h */
2314 had_char_class = false;
2318 had_char_class = false;
2323 /* Discard any (non)matching list bytes that are all 0 at the
2324 end of the map. Decrease the map-length byte too. */
2325 while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
2333 if (syntax & RE_NO_BK_PARENS)
2340 if (syntax & RE_NO_BK_PARENS)
2347 if (syntax & RE_NEWLINE_ALT)
2354 if (syntax & RE_NO_BK_VBAR)
2361 if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
2362 goto handle_interval;
2369 FREE_STACK_RETURN (REG_EESCAPE);
2371 /* Do not translate the character after the \, so that we can
2372 distinguish, e.g., \B from \b, even if we normally would
2373 translate, e.g., B to b. */
2378 if (syntax & RE_NO_BK_PARENS)
2379 goto normal_backslash;
2385 if (COMPILE_STACK_FULL) {
2386 RETALLOC (compile_stack.stack, compile_stack.size << 1,
2387 compile_stack_elt_t);
2388 if (compile_stack.stack == NULL)
2391 compile_stack.size <<= 1;
2394 /* These are the values to restore when we hit end of this
2395 group. They are all relative offsets, so that if the
2396 whole pattern moves because of realloc, they will still
2398 COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
2399 COMPILE_STACK_TOP.fixup_alt_jump
2400 = fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
2401 COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
2402 COMPILE_STACK_TOP.regnum = regnum;
2404 /* We will eventually replace the 0 with the number of
2405 groups inner to this one. But do not push a
2406 start_memory for groups beyond the last one we can
2407 represent in the compiled pattern. */
2408 if (regnum <= MAX_REGNUM) {
2409 COMPILE_STACK_TOP.inner_group_offset = b - bufp->buffer + 2;
2410 BUF_PUSH_3 (start_memory, regnum, 0);
2413 compile_stack.avail++;
2418 /* If we've reached MAX_REGNUM groups, then this open
2419 won't actually generate any code, so we'll have to
2420 clear pending_exact explicitly. */
2426 if (syntax & RE_NO_BK_PARENS)
2427 goto normal_backslash;
2429 if (COMPILE_STACK_EMPTY) {
2430 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD) {
2431 goto normal_backslash;
2433 FREE_STACK_RETURN (REG_ERPAREN);
2438 if (fixup_alt_jump) { /* Push a dummy failure point at the end of the
2439 alternative for a possible future
2440 `pop_failure_jump' to pop. See comments at
2441 `push_dummy_failure' in `re_match_2'. */
2442 BUF_PUSH (push_dummy_failure);
2444 /* We allocated space for this jump when we assigned
2445 to `fixup_alt_jump', in the `handle_alt' case below. */
2446 STORE_JUMP (jump_past_alt, fixup_alt_jump, b - 1);
2449 /* See similar code for backslashed left paren above. */
2450 if (COMPILE_STACK_EMPTY) {
2451 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD) {
2454 FREE_STACK_RETURN (REG_ERPAREN);
2458 /* Since we just checked for an empty stack above, this
2459 ``can't happen''. */
2460 assert (compile_stack.avail != 0);
2462 /* We don't just want to restore into `regnum', because
2463 later groups should continue to be numbered higher,
2464 as in `(ab)c(de)' -- the second group is #2. */
2465 regnum_t this_group_regnum;
2467 compile_stack.avail--;
2468 begalt = bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
2470 = COMPILE_STACK_TOP.fixup_alt_jump
2471 ? bufp->buffer + COMPILE_STACK_TOP.fixup_alt_jump - 1 : 0;
2472 laststart = bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
2473 this_group_regnum = COMPILE_STACK_TOP.regnum;
2474 /* If we've reached MAX_REGNUM groups, then this open
2475 won't actually generate any code, so we'll have to
2476 clear pending_exact explicitly. */
2479 /* We're at the end of the group, so now we know how many
2480 groups were inside this one. */
2481 if (this_group_regnum <= MAX_REGNUM) {
2482 unsigned char *inner_group_loc
2483 = bufp->buffer + COMPILE_STACK_TOP.inner_group_offset;
2485 *inner_group_loc = regnum - this_group_regnum;
2486 BUF_PUSH_3 (stop_memory, this_group_regnum,
2487 regnum - this_group_regnum);
2493 case '|': /* `\|'. */
2494 if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
2495 goto normal_backslash;
2497 if (syntax & RE_LIMITED_OPS)
2500 /* Insert before the previous alternative a jump which
2501 jumps to this alternative if the former fails. */
2502 GET_BUFFER_SPACE (3);
2503 INSERT_JUMP (on_failure_jump, begalt, b + 6);
2507 /* The alternative before this one has a jump after it
2508 which gets executed if it gets matched. Adjust that
2509 jump so it will jump to this alternative's analogous
2510 jump (put in below, which in turn will jump to the next
2511 (if any) alternative's such jump, etc.). The last such
2512 jump jumps to the correct final destination. A picture:
2518 If we are at `b', then fixup_alt_jump right now points to a
2519 three-byte space after `a'. We'll put in the jump, set
2520 fixup_alt_jump to right after `b', and leave behind three
2521 bytes which we'll fill in when we get to after `c'. */
2524 STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
2526 /* Mark and leave space for a jump after this alternative,
2527 to be filled in later either by next alternative or
2528 when know we're at the end of a series of alternatives. */
2530 GET_BUFFER_SPACE (3);
2539 /* If \{ is a literal. */
2540 if (!(syntax & RE_INTERVALS)
2541 /* If we're at `\{' and it's not the open-interval
2543 || ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
2544 || (p - 2 == pattern && p == pend))
2545 goto normal_backslash;
2549 /* If got here, then the syntax allows intervals. */
2551 /* At least (most) this many matches must be made. */
2552 int lower_bound = -1, upper_bound = -1;
2554 beg_interval = p - 1;
2557 if (syntax & RE_NO_BK_BRACES)
2558 goto unfetch_interval;
2560 FREE_STACK_RETURN (REG_EBRACE);
2563 GET_UNSIGNED_NUMBER (lower_bound);
2566 GET_UNSIGNED_NUMBER (upper_bound);
2567 if (upper_bound < 0)
2568 upper_bound = RE_DUP_MAX;
2571 /* Interval such as `{1}' => match exactly once. */
2572 upper_bound = lower_bound;
2574 if (lower_bound < 0 || upper_bound > RE_DUP_MAX
2575 || lower_bound > upper_bound) {
2576 if (syntax & RE_NO_BK_BRACES)
2577 goto unfetch_interval;
2579 FREE_STACK_RETURN (REG_BADBR);
2582 if (!(syntax & RE_NO_BK_BRACES)) {
2584 FREE_STACK_RETURN (REG_EBRACE);
2590 if (syntax & RE_NO_BK_BRACES)
2591 goto unfetch_interval;
2593 FREE_STACK_RETURN (REG_BADBR);
2596 /* We just parsed a valid interval. */
2598 /* If it's invalid to have no preceding re. */
2600 if (syntax & RE_CONTEXT_INVALID_OPS)
2601 FREE_STACK_RETURN (REG_BADRPT);
2602 else if (syntax & RE_CONTEXT_INDEP_OPS)
2605 goto unfetch_interval;
2608 /* If the upper bound is zero, don't want to succeed at
2609 all; jump from `laststart' to `b + 3', which will be
2610 the end of the buffer after we insert the jump. */
2611 if (upper_bound == 0) {
2612 GET_BUFFER_SPACE (3);
2613 INSERT_JUMP (jump, laststart, b + 3);
2617 /* Otherwise, we have a nontrivial interval. When
2618 we're all done, the pattern will look like:
2619 set_number_at <jump count> <upper bound>
2620 set_number_at <succeed_n count> <lower bound>
2621 succeed_n <after jump addr> <succeed_n count>
2623 jump_n <succeed_n addr> <jump count>
2624 (The upper bound and `jump_n' are omitted if
2625 `upper_bound' is 1, though.) */
2626 else { /* If the upper bound is > 1, we need to insert
2627 more at the end of the loop. */
2628 unsigned nbytes = 10 + (upper_bound > 1) * 10;
2630 GET_BUFFER_SPACE (nbytes);
2632 /* Initialize lower bound of the `succeed_n', even
2633 though it will be set during matching by its
2634 attendant `set_number_at' (inserted next),
2635 because `re_compile_fastmap' needs to know.
2636 Jump to the `jump_n' we might insert below. */
2637 INSERT_JUMP2 (succeed_n, laststart,
2638 b + 5 + (upper_bound > 1) * 5, lower_bound);
2641 /* Code to initialize the lower bound. Insert
2642 before the `succeed_n'. The `5' is the last two
2643 bytes of this `set_number_at', plus 3 bytes of
2644 the following `succeed_n'. */
2645 insert_op2 (set_number_at, laststart, 5, lower_bound, b);
2648 if (upper_bound > 1) { /* More than one repetition is allowed, so
2649 append a backward jump to the `succeed_n'
2650 that starts this interval.
2652 When we've reached this during matching,
2653 we'll have matched the interval once, so
2654 jump back only `upper_bound - 1' times. */
2655 STORE_JUMP2 (jump_n, b, laststart + 5, upper_bound - 1);
2658 /* The location we want to set is the second
2659 parameter of the `jump_n'; that is `b-2' as
2660 an absolute address. `laststart' will be
2661 the `set_number_at' we're about to insert;
2662 `laststart+3' the number to set, the source
2663 for the relative address. But we are
2664 inserting into the middle of the pattern --
2665 so everything is getting moved up by 5.
2666 Conclusion: (b - 2) - (laststart + 3) + 5,
2667 i.e., b - laststart.
2669 We insert this at the beginning of the loop
2670 so that if we fail during matching, we'll
2671 reinitialize the bounds. */
2672 insert_op2 (set_number_at, laststart, b - laststart,
2673 upper_bound - 1, b);
2678 beg_interval = NULL;
2683 /* If an invalid interval, match the characters as literals. */
2684 assert (beg_interval);
2686 beg_interval = NULL;
2688 /* normal_char and normal_backslash need `c'. */
2691 if (!(syntax & RE_NO_BK_BRACES)) {
2692 if (p > pattern && p[-1] == '\\')
2693 goto normal_backslash;
2698 /* There is no way to specify the before_dot and after_dot
2699 operators. rms says this is ok. --karl */
2707 BUF_PUSH_2 (syntaxspec, syntax_spec_code[c]);
2713 BUF_PUSH_2 (notsyntaxspec, syntax_spec_code[c]);
2719 if (re_syntax_options & RE_NO_GNU_OPS)
2722 BUF_PUSH (wordchar);
2727 if (re_syntax_options & RE_NO_GNU_OPS)
2730 BUF_PUSH (notwordchar);
2735 if (re_syntax_options & RE_NO_GNU_OPS)
2741 if (re_syntax_options & RE_NO_GNU_OPS)
2747 if (re_syntax_options & RE_NO_GNU_OPS)
2749 BUF_PUSH (wordbound);
2753 if (re_syntax_options & RE_NO_GNU_OPS)
2755 BUF_PUSH (notwordbound);
2759 if (re_syntax_options & RE_NO_GNU_OPS)
2765 if (re_syntax_options & RE_NO_GNU_OPS)
2779 if (syntax & RE_NO_BK_REFS)
2785 FREE_STACK_RETURN (REG_ESUBREG);
2787 /* Can't back reference to a subexpression if inside of it. */
2788 if (group_in_compile_stack (compile_stack, (regnum_t) c1))
2792 BUF_PUSH_2 (duplicate, c1);
2798 if (syntax & RE_BK_PLUS_QM)
2801 goto normal_backslash;
2805 /* You might think it would be useful for \ to mean
2806 not to translate; but if we don't translate it
2807 it will never match anything. */
2815 /* Expects the character in `c'. */
2817 /* If no exactn currently being built. */
2819 /* If last exactn not at current position. */
2820 || pending_exact + *pending_exact + 1 != b
2821 /* We have only one byte following the exactn for the count. */
2822 || *pending_exact == (1 << BYTEWIDTH) - 1
2823 /* If followed by a repetition operator. */
2824 || *p == '*' || *p == '^' || ((syntax & RE_BK_PLUS_QM)
2825 ? *p == '\\' && (p[1] == '+'
2827 : (*p == '+' || *p == '?'))
2828 || ((syntax & RE_INTERVALS)
2829 && ((syntax & RE_NO_BK_BRACES)
2830 ? *p == '{' : (p[0] == '\\' && p[1] == '{')))) {
2831 /* Start building a new exactn. */
2835 BUF_PUSH_2 (exactn, 0);
2836 pending_exact = b - 1;
2843 } /* while p != pend */
2846 /* Through the pattern now. */
2849 STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
2851 if (!COMPILE_STACK_EMPTY)
2852 FREE_STACK_RETURN (REG_EPAREN);
2854 /* If we don't want backtracking, force success
2855 the first time we reach the end of the compiled pattern. */
2856 if (syntax & RE_NO_POSIX_BACKTRACKING)
2859 free (compile_stack.stack); /* __MEM_CHECKED__ */
2861 /* We have succeeded; set the length of the buffer. */
2862 bufp->used = b - bufp->buffer;
2866 DEBUG_PRINT1 ("\nCompiled pattern: \n");
2867 print_compiled_pattern (bufp);
2871 #ifndef MATCH_MAY_ALLOCATE
2872 /* Initialize the failure stack to the largest possible stack. This
2873 isn't necessary unless we're trying to avoid calling alloca in
2874 the search and match routines. */
2876 int num_regs = bufp->re_nsub + 1;
2878 /* Since DOUBLE_FAIL_STACK refuses to double only if the current size
2879 is strictly greater than re_max_failures, the largest possible stack
2880 is 2 * re_max_failures failure points. */
2881 if (fail_stack.size < (2 * re_max_failures * MAX_FAILURE_ITEMS)) {
2882 fail_stack.size = (2 * re_max_failures * MAX_FAILURE_ITEMS);
2885 if (!fail_stack.stack)
2887 = (fail_stack_elt_t *) xmalloc (fail_stack.size
2888 * sizeof (fail_stack_elt_t));
2891 = (fail_stack_elt_t *) xrealloc (fail_stack.stack,
2893 * sizeof (fail_stack_elt_t)));
2894 #else /* not emacs */
2895 if (!fail_stack.stack)
2896 fail_stack.stack = (fail_stack_elt_t *) malloc (fail_stack.size /* __MEM_CHECKED__ */
2899 (fail_stack_elt_t));
2901 fail_stack.stack = (fail_stack_elt_t *) realloc (fail_stack.stack, /* __MEM_CHECKED__ */
2905 (fail_stack_elt_t)));
2906 #endif /* not emacs */
2909 regex_grow_registers (num_regs);
2911 #endif /* not MATCH_MAY_ALLOCATE */
2914 } /* regex_compile */
2916 /* Subroutines for `regex_compile'. */
2918 /* Store OP at LOC followed by two-byte integer parameter ARG. */
2920 static void store_op1 (op, loc, arg)
2925 *loc = (unsigned char) op;
2926 STORE_NUMBER (loc + 1, arg);
2930 /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
2932 static void store_op2 (op, loc, arg1, arg2)
2937 *loc = (unsigned char) op;
2938 STORE_NUMBER (loc + 1, arg1);
2939 STORE_NUMBER (loc + 3, arg2);
2943 /* Copy the bytes from LOC to END to open up three bytes of space at LOC
2944 for OP followed by two-byte integer parameter ARG. */
2946 static void insert_op1 (op, loc, arg, end)
2952 register unsigned char *pfrom = end;
2953 register unsigned char *pto = end + 3;
2955 while (pfrom != loc)
2958 store_op1 (op, loc, arg);
2962 /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
2964 static void insert_op2 (op, loc, arg1, arg2, end)
2970 register unsigned char *pfrom = end;
2971 register unsigned char *pto = end + 5;
2973 while (pfrom != loc)
2976 store_op2 (op, loc, arg1, arg2);
2980 /* P points to just after a ^ in PATTERN. Return true if that ^ comes
2981 after an alternative or a begin-subexpression. We assume there is at
2982 least one character before the ^. */
2984 static boolean at_begline_loc_p (pattern, p, syntax)
2985 const char *pattern, *p;
2986 reg_syntax_t syntax;
2988 const char *prev = p - 2;
2989 boolean prev_prev_backslash = prev > pattern && prev[-1] == '\\';
2992 /* After a subexpression? */
2993 (*prev == '(' && (syntax & RE_NO_BK_PARENS || prev_prev_backslash))
2994 /* After an alternative? */
2995 || (*prev == '|' && (syntax & RE_NO_BK_VBAR || prev_prev_backslash));
2999 /* The dual of at_begline_loc_p. This one is for $. We assume there is
3000 at least one character after the $, i.e., `P < PEND'. */
3002 static boolean at_endline_loc_p (p, pend, syntax)
3003 const char *p, *pend;
3004 reg_syntax_t syntax;
3006 const char *next = p;
3007 boolean next_backslash = *next == '\\';
3008 const char *next_next = p + 1 < pend ? p + 1 : 0;
3011 /* Before a subexpression? */
3012 (syntax & RE_NO_BK_PARENS ? *next == ')'
3013 : next_backslash && next_next && *next_next == ')')
3014 /* Before an alternative? */
3015 || (syntax & RE_NO_BK_VBAR ? *next == '|'
3016 : next_backslash && next_next && *next_next == '|');
3020 /* Returns true if REGNUM is in one of COMPILE_STACK's elements and
3021 false if it's not. */
3023 static boolean group_in_compile_stack (compile_stack, regnum)
3024 compile_stack_type compile_stack;
3029 for (this_element = compile_stack.avail - 1;
3030 this_element >= 0; this_element--)
3031 if (compile_stack.stack[this_element].regnum == regnum)
3038 /* Read the ending character of a range (in a bracket expression) from the
3039 uncompiled pattern *P_PTR (which ends at PEND). We assume the
3040 starting character is in `P[-2]'. (`P[-1]' is the character `-'.)
3041 Then we set the translation of all bits between the starting and
3042 ending characters (inclusive) in the compiled pattern B.
3044 Return an error code.
3046 We use these short variable names so we can use the same macros as
3047 `regex_compile' itself. */
3049 static reg_errcode_t compile_range (p_ptr, pend, translate, syntax, b)
3050 const char **p_ptr, *pend;
3051 RE_TRANSLATE_TYPE translate;
3052 reg_syntax_t syntax;
3057 const char *p = *p_ptr;
3058 unsigned int range_start, range_end;
3063 /* Even though the pattern is a signed `char *', we need to fetch
3064 with unsigned char *'s; if the high bit of the pattern character
3065 is set, the range endpoints will be negative if we fetch using a
3068 We also want to fetch the endpoints without translating them; the
3069 appropriate translation is done in the bit-setting loop below. */
3070 /* The SVR4 compiler on the 3B2 had trouble with unsigned const char *. */
3071 range_start = ((const unsigned char *) p)[-2];
3072 range_end = ((const unsigned char *) p)[0];
3074 /* Have to increment the pointer into the pattern string, so the
3075 caller isn't still at the ending character. */
3078 /* If the start is after the end, the range is empty. */
3079 if (range_start > range_end)
3080 return syntax & RE_NO_EMPTY_RANGES ? REG_ERANGE : REG_NOERROR;
3082 /* Here we see why `this_char' has to be larger than an `unsigned
3083 char' -- the range is inclusive, so if `range_end' == 0xff
3084 (assuming 8-bit characters), we would otherwise go into an infinite
3085 loop, since all characters <= 0xff. */
3086 for (this_char = range_start; this_char <= range_end; this_char++) {
3087 SET_LIST_BIT (TRANSLATE (this_char));
3093 /* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
3094 BUFP. A fastmap records which of the (1 << BYTEWIDTH) possible
3095 characters can start a string that matches the pattern. This fastmap
3096 is used by re_search to skip quickly over impossible starting points.
3098 The caller must supply the address of a (1 << BYTEWIDTH)-byte data
3099 area as BUFP->fastmap.
3101 We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
3104 Returns 0 if we succeed, -2 if an internal error. */
3106 int re_compile_fastmap (bufp)
3107 struct re_pattern_buffer *bufp;
3111 #ifdef MATCH_MAY_ALLOCATE
3112 fail_stack_type fail_stack;
3114 #ifndef REGEX_MALLOC
3117 /* We don't push any register information onto the failure stack. */
3118 unsigned num_regs = 0;
3120 register char *fastmap = bufp->fastmap;
3121 unsigned char *pattern = bufp->buffer;
3122 unsigned char *p = pattern;
3123 register unsigned char *pend = pattern + bufp->used;
3126 /* This holds the pointer to the failure stack, when
3127 it is allocated relocatably. */
3128 fail_stack_elt_t *failure_stack_ptr;
3131 /* Assume that each path through the pattern can be null until
3132 proven otherwise. We set this false at the bottom of switch
3133 statement, to which we get only if a particular path doesn't
3134 match the empty string. */
3135 boolean path_can_be_null = true;
3137 /* We aren't doing a `succeed_n' to begin with. */
3138 boolean succeed_n_p = false;
3140 assert (fastmap != NULL && p != NULL);
3143 bzero (fastmap, 1 << BYTEWIDTH); /* Assume nothing's valid. */
3144 bufp->fastmap_accurate = 1; /* It will be when we're done. */
3145 bufp->can_be_null = 0;
3148 if (p == pend || *p == succeed) {
3149 /* We have reached the (effective) end of pattern. */
3150 if (!FAIL_STACK_EMPTY ()) {
3151 bufp->can_be_null |= path_can_be_null;
3153 /* Reset for next path. */
3154 path_can_be_null = true;
3156 p = fail_stack.stack[--fail_stack.avail].pointer;
3164 /* We should never be about to go beyond the end of the pattern. */
3167 switch (SWITCH_ENUM_CAST ((re_opcode_t) * p++)) {
3169 /* I guess the idea here is to simply not bother with a fastmap
3170 if a backreference is used, since it's too hard to figure out
3171 the fastmap for the corresponding group. Setting
3172 `can_be_null' stops `re_search_2' from using the fastmap, so
3173 that is all we do. */
3175 bufp->can_be_null = 1;
3179 /* Following are the cases which match a character. These end
3188 for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
3189 if (p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH)))
3195 /* Chars beyond end of map must be allowed. */
3196 for (j = *p * BYTEWIDTH; j < (1 << BYTEWIDTH); j++)
3199 for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
3200 if (!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))))
3206 for (j = 0; j < (1 << BYTEWIDTH); j++)
3207 if (SYNTAX (j) == Sword)
3213 for (j = 0; j < (1 << BYTEWIDTH); j++)
3214 if (SYNTAX (j) != Sword)
3221 int fastmap_newline = fastmap['\n'];
3223 /* `.' matches anything ... */
3224 for (j = 0; j < (1 << BYTEWIDTH); j++)
3227 /* ... except perhaps newline. */
3228 if (!(bufp->syntax & RE_DOT_NEWLINE))
3229 fastmap['\n'] = fastmap_newline;
3231 /* Return if we have already set `can_be_null'; if we have,
3232 then the fastmap is irrelevant. Something's wrong here. */
3233 else if (bufp->can_be_null)
3236 /* Otherwise, have to check alternative paths. */
3243 for (j = 0; j < (1 << BYTEWIDTH); j++)
3244 if (SYNTAX (j) == (enum syntaxcode) k)
3251 for (j = 0; j < (1 << BYTEWIDTH); j++)
3252 if (SYNTAX (j) != (enum syntaxcode) k)
3257 /* All cases after this match the empty string. These end with
3277 case push_dummy_failure:
3282 case pop_failure_jump:
3283 case maybe_pop_jump:
3286 case dummy_failure_jump:
3287 EXTRACT_NUMBER_AND_INCR (j, p);
3292 /* Jump backward implies we just went through the body of a
3293 loop and matched nothing. Opcode jumped to should be
3294 `on_failure_jump' or `succeed_n'. Just treat it like an
3295 ordinary jump. For a * loop, it has pushed its failure
3296 point already; if so, discard that as redundant. */
3297 if ((re_opcode_t) * p != on_failure_jump
3298 && (re_opcode_t) * p != succeed_n)
3302 EXTRACT_NUMBER_AND_INCR (j, p);
3305 /* If what's on the stack is where we are now, pop it. */
3306 if (!FAIL_STACK_EMPTY ()
3307 && fail_stack.stack[fail_stack.avail - 1].pointer == p)
3313 case on_failure_jump:
3314 case on_failure_keep_string_jump:
3315 handle_on_failure_jump:
3316 EXTRACT_NUMBER_AND_INCR (j, p);
3318 /* For some patterns, e.g., `(a?)?', `p+j' here points to the
3319 end of the pattern. We don't want to push such a point,
3320 since when we restore it above, entering the switch will
3321 increment `p' past the end of the pattern. We don't need
3322 to push such a point since we obviously won't find any more
3323 fastmap entries beyond `pend'. Such a pattern can match
3324 the null string, though. */
3326 if (!PUSH_PATTERN_OP (p + j, fail_stack)) {
3327 RESET_FAIL_STACK ();
3332 bufp->can_be_null = 1;
3335 EXTRACT_NUMBER_AND_INCR (k, p); /* Skip the n. */
3336 succeed_n_p = false;
3343 /* Get to the number of times to succeed. */
3346 /* Increment p past the n for when k != 0. */
3347 EXTRACT_NUMBER_AND_INCR (k, p);
3350 succeed_n_p = true; /* Spaghetti code alert. */
3351 goto handle_on_failure_jump;
3368 abort (); /* We have listed all the cases. */
3371 /* Getting here means we have found the possible starting
3372 characters for one path of the pattern -- and that the empty
3373 string does not match. We need not follow this path further.
3374 Instead, look at the next alternative (remembered on the
3375 stack), or quit if no more. The test at the top of the loop
3376 does these things. */
3377 path_can_be_null = false;
3381 /* Set `can_be_null' for the last path (also the first path, if the
3382 pattern is empty). */
3383 bufp->can_be_null |= path_can_be_null;
3386 RESET_FAIL_STACK ();
3388 } /* re_compile_fastmap */
3390 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
3391 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
3392 this memory for recording register information. STARTS and ENDS
3393 must be allocated using the malloc library routine, and must each
3394 be at least NUM_REGS * sizeof (regoff_t) bytes long.
3396 If NUM_REGS == 0, then subsequent matches should allocate their own
3399 Unless this function is called, the first search or match using
3400 PATTERN_BUFFER will allocate its own register data, without
3401 freeing the old data. */
3403 void re_set_registers (bufp, regs, num_regs, starts, ends)
3404 struct re_pattern_buffer *bufp;
3405 struct re_registers *regs;
3407 regoff_t *starts, *ends;
3410 bufp->regs_allocated = REGS_REALLOCATE;
3411 regs->num_regs = num_regs;
3412 regs->start = starts;
3416 bufp->regs_allocated = REGS_UNALLOCATED;
3418 regs->start = regs->end = (regoff_t *) 0;
3422 /* Searching routines. */
3424 /* Like re_search_2, below, but only one string is specified, and
3425 doesn't let you say where to stop matching. */
3427 int re_search (bufp, string, size, startpos, range, regs)
3428 struct re_pattern_buffer *bufp;
3430 int size, startpos, range;
3431 struct re_registers *regs;
3433 return re_search_2 (bufp, NULL, 0, string, size, startpos, range,
3438 /* Using the compiled pattern in BUFP->buffer, first tries to match the
3439 virtual concatenation of STRING1 and STRING2, starting first at index
3440 STARTPOS, then at STARTPOS + 1, and so on.
3442 STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
3444 RANGE is how far to scan while trying to match. RANGE = 0 means try
3445 only at STARTPOS; in general, the last start tried is STARTPOS +
3448 In REGS, return the indices of the virtual concatenation of STRING1
3449 and STRING2 that matched the entire BUFP->buffer and its contained
3452 Do not consider matching one past the index STOP in the virtual
3453 concatenation of STRING1 and STRING2.
3455 We return either the position in the strings at which the match was
3456 found, -1 if no match, or -2 if error (such as failure
3460 re_search_2 (bufp, string1, size1, string2, size2, startpos, range, regs,
3462 struct re_pattern_buffer *bufp;
3463 const char *string1, *string2;
3467 struct re_registers *regs;
3471 register char *fastmap = bufp->fastmap;
3472 register RE_TRANSLATE_TYPE translate = bufp->translate;
3473 int total_size = size1 + size2;
3474 int endpos = startpos + range;
3476 /* Check for out-of-range STARTPOS. */
3477 if (startpos < 0 || startpos > total_size)
3480 /* Fix up RANGE if it might eventually take us outside
3481 the virtual concatenation of STRING1 and STRING2.
3482 Make sure we won't move STARTPOS below 0 or above TOTAL_SIZE. */
3484 range = 0 - startpos;
3485 else if (endpos > total_size)
3486 range = total_size - startpos;
3488 /* If the search isn't to be a backwards one, don't waste time in a
3489 search for a pattern that must be anchored. */
3490 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == begbuf && range > 0) {
3498 /* In a forward search for something that starts with \=.
3499 don't keep searching past point. */
3500 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == at_dot && range > 0) {
3501 range = PT - startpos;
3507 /* Update the fastmap now if not correct already. */
3508 if (fastmap && !bufp->fastmap_accurate)
3509 if (re_compile_fastmap (bufp) == -2)
3512 /* Loop through the string, looking for a place to start matching. */
3514 /* If a fastmap is supplied, skip quickly over characters that
3515 cannot be the start of a match. If the pattern can match the
3516 null string, however, we don't need to skip characters; we want
3517 the first null string. */
3518 if (fastmap && startpos < total_size && !bufp->can_be_null) {
3519 if (range > 0) { /* Searching forwards. */
3520 register const char *d;
3521 register int lim = 0;
3524 if (startpos < size1 && startpos + range >= size1)
3525 lim = range - (size1 - startpos);
3527 d = (startpos >= size1 ? string2 - size1 : string1) + startpos;
3529 /* Written out as an if-else to avoid testing `translate'
3532 while (range > lim && !fastmap[(unsigned char)
3533 translate[(unsigned char) *d++]])
3536 while (range > lim && !fastmap[(unsigned char) *d++])
3539 startpos += irange - range;
3541 else { /* Searching backwards. */
3543 register char c = (size1 == 0 || startpos >= size1
3544 ? string2[startpos - size1]
3545 : string1[startpos]);
3547 if (!fastmap[(unsigned char) TRANSLATE (c)])
3552 /* If can't match the null string, and that's all we have left, fail. */
3553 if (range >= 0 && startpos == total_size && fastmap && !bufp->can_be_null)
3556 val = re_match_2_internal (bufp, string1, size1, string2, size2,
3557 startpos, regs, stop);
3558 #ifndef REGEX_MALLOC
3573 else if (range > 0) {
3585 /* This converts PTR, a pointer into one of the search strings `string1'
3586 and `string2' into an offset from the beginning of that string. */
3587 #define POINTER_TO_OFFSET(ptr) \
3588 (FIRST_STRING_P (ptr) \
3589 ? ((regoff_t) ((ptr) - string1)) \
3590 : ((regoff_t) ((ptr) - string2 + size1)))
3592 /* Macros for dealing with the split strings in re_match_2. */
3594 #define MATCHING_IN_FIRST_STRING (dend == end_match_1)
3596 /* Call before fetching a character with *d. This switches over to
3597 string2 if necessary. */
3598 #define PREFETCH() \
3601 /* End of string2 => fail. */ \
3602 if (dend == end_match_2) \
3604 /* End of string1 => advance to string2. */ \
3606 dend = end_match_2; \
3610 /* Test if at very beginning or at very end of the virtual concatenation
3611 of `string1' and `string2'. If only one string, it's `string2'. */
3612 #define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
3613 #define AT_STRINGS_END(d) ((d) == end2)
3616 /* Test if D points to a character which is word-constituent. We have
3617 two special cases to check for: if past the end of string1, look at
3618 the first character in string2; and if before the beginning of
3619 string2, look at the last character in string1. */
3620 #define WORDCHAR_P(d) \
3621 (SYNTAX ((d) == end1 ? *string2 \
3622 : (d) == string2 - 1 ? *(end1 - 1) : *(d)) \
3625 /* Disabled due to a compiler bug -- see comment at case wordbound */
3627 /* Test if the character before D and the one at D differ with respect
3628 to being word-constituent. */
3629 #define AT_WORD_BOUNDARY(d) \
3630 (AT_STRINGS_BEG (d) || AT_STRINGS_END (d) \
3631 || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
3634 /* Free everything we malloc. */
3635 #ifdef MATCH_MAY_ALLOCATE
3636 #define FREE_VAR(var) if (var) REGEX_FREE (var); var = NULL
3637 #define FREE_VARIABLES() \
3639 REGEX_FREE_STACK (fail_stack.stack); \
3640 FREE_VAR (regstart); \
3641 FREE_VAR (regend); \
3642 FREE_VAR (old_regstart); \
3643 FREE_VAR (old_regend); \
3644 FREE_VAR (best_regstart); \
3645 FREE_VAR (best_regend); \
3646 FREE_VAR (reg_info); \
3647 FREE_VAR (reg_dummy); \
3648 FREE_VAR (reg_info_dummy); \
3651 #define FREE_VARIABLES() ((void)0) /* Do nothing! But inhibit gcc warning. */
3652 #endif /* not MATCH_MAY_ALLOCATE */
3654 /* These values must meet several constraints. They must not be valid
3655 register values; since we have a limit of 255 registers (because
3656 we use only one byte in the pattern for the register number), we can
3657 use numbers larger than 255. They must differ by 1, because of
3658 NUM_FAILURE_ITEMS above. And the value for the lowest register must
3659 be larger than the value for the highest register, so we do not try
3660 to actually save any registers when none are active. */
3661 #define NO_HIGHEST_ACTIVE_REG (1 << BYTEWIDTH)
3662 #define NO_LOWEST_ACTIVE_REG (NO_HIGHEST_ACTIVE_REG + 1)
3664 /* Matching routines. */
3666 #ifndef emacs /* Emacs never uses this. */
3667 /* re_match is like re_match_2 except it takes only a single string. */
3669 int re_match (bufp, string, size, pos, regs)
3670 struct re_pattern_buffer *bufp;
3673 struct re_registers *regs;
3675 int result = re_match_2_internal (bufp, NULL, 0, string, size,
3678 #ifndef REGEX_MALLOC
3685 #endif /* not emacs */
3687 static boolean group_match_null_string_p _RE_ARGS ((unsigned char **p,
3689 register_info_type *
3691 static boolean alt_match_null_string_p
3692 _RE_ARGS ((unsigned char *p, unsigned char *end,
3693 register_info_type * reg_info));
3694 static boolean common_op_match_null_string_p
3695 _RE_ARGS ((unsigned char **p, unsigned char *end,
3696 register_info_type * reg_info));
3697 static int bcmp_translate
3698 _RE_ARGS ((const char *s1, const char *s2, int len, char *translate));
3700 /* re_match_2 matches the compiled pattern in BUFP against the
3701 the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
3702 and SIZE2, respectively). We start matching at POS, and stop
3705 If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
3706 store offsets for the substring each group matched in REGS. See the
3707 documentation for exactly how many groups we fill.
3709 We return -1 if no match, -2 if an internal error (such as the
3710 failure stack overflowing). Otherwise, we return the length of the
3711 matched substring. */
3713 int re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
3714 struct re_pattern_buffer *bufp;
3715 const char *string1, *string2;
3718 struct re_registers *regs;
3721 int result = re_match_2_internal (bufp, string1, size1, string2, size2,
3724 #ifndef REGEX_MALLOC
3732 /* This is a separate function so that we can force an alloca cleanup
3735 re_match_2_internal (bufp, string1, size1, string2, size2, pos, regs, stop)
3736 struct re_pattern_buffer *bufp;
3737 const char *string1, *string2;
3740 struct re_registers *regs;
3743 /* General temporaries. */
3747 /* Just past the end of the corresponding string. */
3748 const char *end1, *end2;
3750 /* Pointers into string1 and string2, just past the last characters in
3751 each to consider matching. */
3752 const char *end_match_1, *end_match_2;
3754 /* Where we are in the data, and the end of the current string. */
3755 const char *d, *dend;
3757 /* Where we are in the pattern, and the end of the pattern. */
3758 unsigned char *p = bufp->buffer;
3759 register unsigned char *pend = p + bufp->used;
3761 /* Mark the opcode just after a start_memory, so we can test for an
3762 empty subpattern when we get to the stop_memory. */
3763 unsigned char *just_past_start_mem = 0;
3765 /* We use this to map every character in the string. */
3766 RE_TRANSLATE_TYPE translate = bufp->translate;
3768 /* Failure point stack. Each place that can handle a failure further
3769 down the line pushes a failure point on this stack. It consists of
3770 restart, regend, and reg_info for all registers corresponding to
3771 the subexpressions we're currently inside, plus the number of such
3772 registers, and, finally, two char *'s. The first char * is where
3773 to resume scanning the pattern; the second one is where to resume
3774 scanning the strings. If the latter is zero, the failure point is
3775 a ``dummy''; if a failure happens and the failure point is a dummy,
3776 it gets discarded and the next next one is tried. */
3777 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
3778 fail_stack_type fail_stack;
3781 static unsigned failure_id = 0;
3782 unsigned nfailure_points_pushed = 0, nfailure_points_popped = 0;
3786 /* This holds the pointer to the failure stack, when
3787 it is allocated relocatably. */
3788 fail_stack_elt_t *failure_stack_ptr;
3791 /* We fill all the registers internally, independent of what we
3792 return, for use in backreferences. The number here includes
3793 an element for register zero. */
3794 size_t num_regs = bufp->re_nsub + 1;
3796 /* The currently active registers. */
3797 active_reg_t lowest_active_reg = NO_LOWEST_ACTIVE_REG;
3798 active_reg_t highest_active_reg = NO_HIGHEST_ACTIVE_REG;
3800 /* Information on the contents of registers. These are pointers into
3801 the input strings; they record just what was matched (on this
3802 attempt) by a subexpression part of the pattern, that is, the
3803 regnum-th regstart pointer points to where in the pattern we began
3804 matching and the regnum-th regend points to right after where we
3805 stopped matching the regnum-th subexpression. (The zeroth register
3806 keeps track of what the whole pattern matches.) */
3807 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3808 const char **regstart, **regend;
3811 /* If a group that's operated upon by a repetition operator fails to
3812 match anything, then the register for its start will need to be
3813 restored because it will have been set to wherever in the string we
3814 are when we last see its open-group operator. Similarly for a
3816 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3817 const char **old_regstart, **old_regend;
3820 /* The is_active field of reg_info helps us keep track of which (possibly
3821 nested) subexpressions we are currently in. The matched_something
3822 field of reg_info[reg_num] helps us tell whether or not we have
3823 matched any of the pattern so far this time through the reg_num-th
3824 subexpression. These two fields get reset each time through any
3825 loop their register is in. */
3826 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
3827 register_info_type *reg_info;
3830 /* The following record the register info as found in the above
3831 variables when we find a match better than any we've seen before.
3832 This happens as we backtrack through the failure points, which in
3833 turn happens only if we have not yet matched the entire string. */
3834 unsigned best_regs_set = false;
3836 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3837 const char **best_regstart, **best_regend;
3840 /* Logically, this is `best_regend[0]'. But we don't want to have to
3841 allocate space for that if we're not allocating space for anything
3842 else (see below). Also, we never need info about register 0 for
3843 any of the other register vectors, and it seems rather a kludge to
3844 treat `best_regend' differently than the rest. So we keep track of
3845 the end of the best match so far in a separate variable. We
3846 initialize this to NULL so that when we backtrack the first time
3847 and need to test it, it's not garbage. */
3848 const char *match_end = NULL;
3850 /* This helps SET_REGS_MATCHED avoid doing redundant work. */
3851 int set_regs_matched_done = 0;
3853 /* Used when we pop values we don't care about. */
3854 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3855 const char **reg_dummy;
3856 register_info_type *reg_info_dummy;
3860 /* Counts the total number of registers pushed. */
3861 unsigned num_regs_pushed = 0;
3864 DEBUG_PRINT1 ("\n\nEntering re_match_2.\n");
3868 #ifdef MATCH_MAY_ALLOCATE
3869 /* Do not bother to initialize all the register variables if there are
3870 no groups in the pattern, as it takes a fair amount of time. If
3871 there are groups, we include space for register 0 (the whole
3872 pattern), even though we never use it, since it simplifies the
3873 array indexing. We should fix this. */
3874 if (bufp->re_nsub) {
3875 regstart = REGEX_TALLOC (num_regs, const char *);
3876 regend = REGEX_TALLOC (num_regs, const char *);
3877 old_regstart = REGEX_TALLOC (num_regs, const char *);
3878 old_regend = REGEX_TALLOC (num_regs, const char *);
3879 best_regstart = REGEX_TALLOC (num_regs, const char *);
3880 best_regend = REGEX_TALLOC (num_regs, const char *);
3882 reg_info = REGEX_TALLOC (num_regs, register_info_type);
3883 reg_dummy = REGEX_TALLOC (num_regs, const char *);
3885 reg_info_dummy = REGEX_TALLOC (num_regs, register_info_type);
3887 if (!(regstart && regend && old_regstart && old_regend && reg_info
3888 && best_regstart && best_regend && reg_dummy && reg_info_dummy)) {
3894 /* We must initialize all our variables to NULL, so that
3895 `FREE_VARIABLES' doesn't try to free them. */
3896 regstart = regend = old_regstart = old_regend = best_regstart
3897 = best_regend = reg_dummy = NULL;
3898 reg_info = reg_info_dummy = (register_info_type *) NULL;
3900 #endif /* MATCH_MAY_ALLOCATE */
3902 /* The starting position is bogus. */
3903 if (pos < 0 || pos > size1 + size2) {
3908 /* Initialize subexpression text positions to -1 to mark ones that no
3909 start_memory/stop_memory has been seen for. Also initialize the
3910 register information struct. */
3911 for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++) {
3912 regstart[mcnt] = regend[mcnt]
3913 = old_regstart[mcnt] = old_regend[mcnt] = REG_UNSET_VALUE;
3915 REG_MATCH_NULL_STRING_P (reg_info[mcnt]) = MATCH_NULL_UNSET_VALUE;
3916 IS_ACTIVE (reg_info[mcnt]) = 0;
3917 MATCHED_SOMETHING (reg_info[mcnt]) = 0;
3918 EVER_MATCHED_SOMETHING (reg_info[mcnt]) = 0;
3921 /* We move `string1' into `string2' if the latter's empty -- but not if
3922 `string1' is null. */
3923 if (size2 == 0 && string1 != NULL) {
3929 end1 = string1 + size1;
3930 end2 = string2 + size2;
3932 /* Compute where to stop matching, within the two strings. */
3933 if (stop <= size1) {
3934 end_match_1 = string1 + stop;
3935 end_match_2 = string2;
3939 end_match_2 = string2 + stop - size1;
3942 /* `p' scans through the pattern as `d' scans through the data.
3943 `dend' is the end of the input string that `d' points within. `d'
3944 is advanced into the following input string whenever necessary, but
3945 this happens before fetching; therefore, at the beginning of the
3946 loop, `d' can be pointing at the end of a string, but it cannot
3948 if (size1 > 0 && pos <= size1) {
3953 d = string2 + pos - size1;
3957 DEBUG_PRINT1 ("The compiled pattern is:\n");
3958 DEBUG_PRINT_COMPILED_PATTERN (bufp, p, pend);
3959 DEBUG_PRINT1 ("The string to match is: `");
3960 DEBUG_PRINT_DOUBLE_STRING (d, string1, size1, string2, size2);
3961 DEBUG_PRINT1 ("'\n");
3963 /* This loops over pattern commands. It exits by returning from the
3964 function if the match is complete, or it drops through if the match
3965 fails at this starting point in the input data. */
3968 DEBUG_PRINT2 ("\n%p: ", p);
3970 DEBUG_PRINT2 ("\n0x%x: ", p);
3973 if (p == pend) { /* End of pattern means we might have succeeded. */
3974 DEBUG_PRINT1 ("end of pattern ... ");
3976 /* If we haven't matched the entire string, and we want the
3977 longest match, try backtracking. */
3978 if (d != end_match_2) {
3979 /* 1 if this match ends in the same string (string1 or string2)
3980 as the best previous match. */
3981 boolean same_str_p = (FIRST_STRING_P (match_end)
3982 == MATCHING_IN_FIRST_STRING);
3984 /* 1 if this match is the best seen so far. */
3985 boolean best_match_p;
3987 /* AIX compiler got confused when this was combined
3988 with the previous declaration. */
3990 best_match_p = d > match_end;
3992 best_match_p = !MATCHING_IN_FIRST_STRING;
3994 DEBUG_PRINT1 ("backtracking.\n");
3996 if (!FAIL_STACK_EMPTY ()) { /* More failure points to try. */
3998 /* If exceeds best match so far, save it. */
3999 if (!best_regs_set || best_match_p) {
4000 best_regs_set = true;
4003 DEBUG_PRINT1 ("\nSAVING match as best so far.\n");
4005 for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++) {
4006 best_regstart[mcnt] = regstart[mcnt];
4007 best_regend[mcnt] = regend[mcnt];
4013 /* If no failure points, don't restore garbage. And if
4014 last match is real best match, don't restore second
4016 else if (best_regs_set && !best_match_p) {
4018 /* Restore best match. It may happen that `dend ==
4019 end_match_1' while the restored d is in string2.
4020 For example, the pattern `x.*y.*z' against the
4021 strings `x-' and `y-z-', if the two strings are
4022 not consecutive in memory. */
4023 DEBUG_PRINT1 ("Restoring best registers.\n");
4026 dend = ((d >= string1 && d <= end1)
4027 ? end_match_1 : end_match_2);
4029 for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++) {
4030 regstart[mcnt] = best_regstart[mcnt];
4031 regend[mcnt] = best_regend[mcnt];
4034 } /* d != end_match_2 */
4037 DEBUG_PRINT1 ("Accepting match.\n");
4039 /* If caller wants register contents data back, do it. */
4040 if (regs && !bufp->no_sub) {
4041 /* Have the register data arrays been allocated? */
4042 if (bufp->regs_allocated == REGS_UNALLOCATED) { /* No. So allocate them with malloc. We need one
4043 extra element beyond `num_regs' for the `-1' marker
4045 regs->num_regs = MAX (RE_NREGS, num_regs + 1);
4046 regs->start = TALLOC (regs->num_regs, regoff_t);
4047 regs->end = TALLOC (regs->num_regs, regoff_t);
4048 if (regs->start == NULL || regs->end == NULL) {
4052 bufp->regs_allocated = REGS_REALLOCATE;
4054 else if (bufp->regs_allocated == REGS_REALLOCATE) { /* Yes. If we need more elements than were already
4055 allocated, reallocate them. If we need fewer, just
4057 if (regs->num_regs < num_regs + 1) {
4058 regs->num_regs = num_regs + 1;
4059 RETALLOC (regs->start, regs->num_regs, regoff_t);
4060 RETALLOC (regs->end, regs->num_regs, regoff_t);
4061 if (regs->start == NULL || regs->end == NULL) {
4068 /* These braces fend off a "empty body in an else-statement"
4069 warning under GCC when assert expands to nothing. */
4070 assert (bufp->regs_allocated == REGS_FIXED);
4073 /* Convert the pointer data in `regstart' and `regend' to
4074 indices. Register zero has to be set differently,
4075 since we haven't kept track of any info for it. */
4076 if (regs->num_regs > 0) {
4077 regs->start[0] = pos;
4078 regs->end[0] = (MATCHING_IN_FIRST_STRING
4079 ? ((regoff_t) (d - string1))
4080 : ((regoff_t) (d - string2 + size1)));
4083 /* Go through the first `min (num_regs, regs->num_regs)'
4084 registers, since that is all we initialized. */
4085 for (mcnt = 1; (unsigned) mcnt < MIN (num_regs, regs->num_regs);
4087 if (REG_UNSET (regstart[mcnt]) || REG_UNSET (regend[mcnt]))
4088 regs->start[mcnt] = regs->end[mcnt] = -1;
4091 = (regoff_t) POINTER_TO_OFFSET (regstart[mcnt]);
4093 = (regoff_t) POINTER_TO_OFFSET (regend[mcnt]);
4097 /* If the regs structure we return has more elements than
4098 were in the pattern, set the extra elements to -1. If
4099 we (re)allocated the registers, this is the case,
4100 because we always allocate enough to have at least one
4102 for (mcnt = num_regs; (unsigned) mcnt < regs->num_regs; mcnt++)
4103 regs->start[mcnt] = regs->end[mcnt] = -1;
4104 } /* regs && !bufp->no_sub */
4106 DEBUG_PRINT4 ("%u failure points pushed, %u popped (%u remain).\n",
4107 nfailure_points_pushed, nfailure_points_popped,
4108 nfailure_points_pushed - nfailure_points_popped);
4109 DEBUG_PRINT2 ("%u registers pushed.\n", num_regs_pushed);
4111 mcnt = d - pos - (MATCHING_IN_FIRST_STRING ? string1 : string2 - size1);
4113 DEBUG_PRINT2 ("Returning %d from re_match_2.\n", mcnt);
4119 /* Otherwise match next pattern command. */
4120 switch (SWITCH_ENUM_CAST ((re_opcode_t) * p++)) {
4121 /* Ignore these. Used to ignore the n of succeed_n's which
4122 currently have n == 0. */
4124 DEBUG_PRINT1 ("EXECUTING no_op.\n");
4128 DEBUG_PRINT1 ("EXECUTING succeed.\n");
4131 /* Match the next n pattern characters exactly. The following
4132 byte in the pattern defines n, and the n bytes after that
4133 are the characters to match. */
4136 DEBUG_PRINT2 ("EXECUTING exactn %d.\n", mcnt);
4138 /* This is written out as an if-else so we don't waste time
4139 testing `translate' inside the loop. */
4143 if ((unsigned char) translate[(unsigned char) *d++]
4144 != (unsigned char) *p++)
4152 if (*d++ != (char) *p++)
4157 SET_REGS_MATCHED ();
4161 /* Match any character except possibly a newline or a null. */
4163 DEBUG_PRINT1 ("EXECUTING anychar.\n");
4167 if ((!(bufp->syntax & RE_DOT_NEWLINE) && TRANSLATE (*d) == '\n')
4168 || (bufp->syntax & RE_DOT_NOT_NULL && TRANSLATE (*d) == '\000'))
4171 SET_REGS_MATCHED ();
4172 DEBUG_PRINT2 (" Matched `%d'.\n", *d);
4180 register unsigned char c;
4181 boolean not = (re_opcode_t) * (p - 1) == charset_not;
4183 DEBUG_PRINT2 ("EXECUTING charset%s.\n", not ? "_not" : "");
4186 c = TRANSLATE (*d); /* The character to match. */
4188 /* Cast to `unsigned' instead of `unsigned char' in case the
4189 bit list is a full 32 bytes long. */
4190 if (c < (unsigned) (*p * BYTEWIDTH)
4191 && p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4199 SET_REGS_MATCHED ();
4205 /* The beginning of a group is represented by start_memory.
4206 The arguments are the register number in the next byte, and the
4207 number of groups inner to this one in the next. The text
4208 matched within the group is recorded (in the internal
4209 registers data structure) under the register number. */
4211 DEBUG_PRINT3 ("EXECUTING start_memory %d (%d):\n", *p, p[1]);
4213 /* Find out if this group can match the empty string. */
4214 p1 = p; /* To send to group_match_null_string_p. */
4216 if (REG_MATCH_NULL_STRING_P (reg_info[*p]) == MATCH_NULL_UNSET_VALUE)
4217 REG_MATCH_NULL_STRING_P (reg_info[*p])
4218 = group_match_null_string_p (&p1, pend, reg_info);
4220 /* Save the position in the string where we were the last time
4221 we were at this open-group operator in case the group is
4222 operated upon by a repetition operator, e.g., with `(a*)*b'
4223 against `ab'; then we want to ignore where we are now in
4224 the string in case this attempt to match fails. */
4225 old_regstart[*p] = REG_MATCH_NULL_STRING_P (reg_info[*p])
4226 ? REG_UNSET (regstart[*p]) ? d : regstart[*p]
4228 DEBUG_PRINT2 (" old_regstart: %d\n",
4229 POINTER_TO_OFFSET (old_regstart[*p]));
4232 DEBUG_PRINT2 (" regstart: %d\n", POINTER_TO_OFFSET (regstart[*p]));
4234 IS_ACTIVE (reg_info[*p]) = 1;
4235 MATCHED_SOMETHING (reg_info[*p]) = 0;
4237 /* Clear this whenever we change the register activity status. */
4238 set_regs_matched_done = 0;
4240 /* This is the new highest active register. */
4241 highest_active_reg = *p;
4243 /* If nothing was active before, this is the new lowest active
4245 if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
4246 lowest_active_reg = *p;
4248 /* Move past the register number and inner group count. */
4250 just_past_start_mem = p;
4255 /* The stop_memory opcode represents the end of a group. Its
4256 arguments are the same as start_memory's: the register
4257 number, and the number of inner groups. */
4259 DEBUG_PRINT3 ("EXECUTING stop_memory %d (%d):\n", *p, p[1]);
4261 /* We need to save the string position the last time we were at
4262 this close-group operator in case the group is operated
4263 upon by a repetition operator, e.g., with `((a*)*(b*)*)*'
4264 against `aba'; then we want to ignore where we are now in
4265 the string in case this attempt to match fails. */
4266 old_regend[*p] = REG_MATCH_NULL_STRING_P (reg_info[*p])
4267 ? REG_UNSET (regend[*p]) ? d : regend[*p]
4269 DEBUG_PRINT2 (" old_regend: %d\n",
4270 POINTER_TO_OFFSET (old_regend[*p]));
4273 DEBUG_PRINT2 (" regend: %d\n", POINTER_TO_OFFSET (regend[*p]));
4275 /* This register isn't active anymore. */
4276 IS_ACTIVE (reg_info[*p]) = 0;
4278 /* Clear this whenever we change the register activity status. */
4279 set_regs_matched_done = 0;
4281 /* If this was the only register active, nothing is active
4283 if (lowest_active_reg == highest_active_reg) {
4284 lowest_active_reg = NO_LOWEST_ACTIVE_REG;
4285 highest_active_reg = NO_HIGHEST_ACTIVE_REG;
4287 else { /* We must scan for the new highest active register, since
4288 it isn't necessarily one less than now: consider
4289 (a(b)c(d(e)f)g). When group 3 ends, after the f), the
4290 new highest active register is 1. */
4291 unsigned char r = *p - 1;
4293 while (r > 0 && !IS_ACTIVE (reg_info[r]))
4296 /* If we end up at register zero, that means that we saved
4297 the registers as the result of an `on_failure_jump', not
4298 a `start_memory', and we jumped to past the innermost
4299 `stop_memory'. For example, in ((.)*) we save
4300 registers 1 and 2 as a result of the *, but when we pop
4301 back to the second ), we are at the stop_memory 1.
4302 Thus, nothing is active. */
4304 lowest_active_reg = NO_LOWEST_ACTIVE_REG;
4305 highest_active_reg = NO_HIGHEST_ACTIVE_REG;
4308 highest_active_reg = r;
4311 /* If just failed to match something this time around with a
4312 group that's operated on by a repetition operator, try to
4313 force exit from the ``loop'', and restore the register
4314 information for this group that we had before trying this
4316 if ((!MATCHED_SOMETHING (reg_info[*p])
4317 || just_past_start_mem == p - 1)
4318 && (p + 2) < pend) {
4319 boolean is_a_jump_n = false;
4323 switch ((re_opcode_t) * p1++) {
4326 case pop_failure_jump:
4327 case maybe_pop_jump:
4329 case dummy_failure_jump:
4330 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4340 /* If the next operation is a jump backwards in the pattern
4341 to an on_failure_jump right before the start_memory
4342 corresponding to this stop_memory, exit from the loop
4343 by forcing a failure after pushing on the stack the
4344 on_failure_jump's jump in the pattern, and d. */
4345 if (mcnt < 0 && (re_opcode_t) * p1 == on_failure_jump
4346 && (re_opcode_t) p1[3] == start_memory && p1[4] == *p) {
4347 /* If this group ever matched anything, then restore
4348 what its registers were before trying this last
4349 failed match, e.g., with `(a*)*b' against `ab' for
4350 regstart[1], and, e.g., with `((a*)*(b*)*)*'
4351 against `aba' for regend[3].
4353 Also restore the registers for inner groups for,
4354 e.g., `((a*)(b*))*' against `aba' (register 3 would
4355 otherwise get trashed). */
4357 if (EVER_MATCHED_SOMETHING (reg_info[*p])) {
4360 EVER_MATCHED_SOMETHING (reg_info[*p]) = 0;
4362 /* Restore this and inner groups' (if any) registers. */
4363 for (r = *p; r < (unsigned) *p + (unsigned) *(p + 1); r++) {
4364 regstart[r] = old_regstart[r];
4366 /* xx why this test? */
4367 if (old_regend[r] >= regstart[r])
4368 regend[r] = old_regend[r];
4372 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4373 PUSH_FAILURE_POINT (p1 + mcnt, d, -2);
4379 /* Move past the register number and the inner group count. */
4384 /* \<digit> has been turned into a `duplicate' command which is
4385 followed by the numeric value of <digit> as the register number. */
4388 register const char *d2, *dend2;
4389 int regno = *p++; /* Get which register to match against. */
4391 DEBUG_PRINT2 ("EXECUTING duplicate %d.\n", regno);
4393 /* Can't back reference a group which we've never matched. */
4394 if (REG_UNSET (regstart[regno]) || REG_UNSET (regend[regno]))
4397 /* Where in input to try to start matching. */
4398 d2 = regstart[regno];
4400 /* Where to stop matching; if both the place to start and
4401 the place to stop matching are in the same string, then
4402 set to the place to stop, otherwise, for now have to use
4403 the end of the first string. */
4405 dend2 = ((FIRST_STRING_P (regstart[regno])
4406 == FIRST_STRING_P (regend[regno]))
4407 ? regend[regno] : end_match_1);
4409 /* If necessary, advance to next segment in register
4411 while (d2 == dend2) {
4412 if (dend2 == end_match_2)
4414 if (dend2 == regend[regno])
4417 /* End of string1 => advance to string2. */
4419 dend2 = regend[regno];
4421 /* At end of register contents => success */
4425 /* If necessary, advance to next segment in data. */
4428 /* How many characters left in this segment to match. */
4431 /* Want how many consecutive characters we can match in
4432 one shot, so, if necessary, adjust the count. */
4433 if (mcnt > dend2 - d2)
4436 /* Compare that many; failure if mismatch, else move
4438 if (translate ? bcmp_translate (d, d2, mcnt, translate)
4439 : bcmp (d, d2, mcnt))
4441 d += mcnt, d2 += mcnt;
4443 /* Do this because we've match some characters. */
4444 SET_REGS_MATCHED ();
4450 /* begline matches the empty string at the beginning of the string
4451 (unless `not_bol' is set in `bufp'), and, if
4452 `newline_anchor' is set, after newlines. */
4454 DEBUG_PRINT1 ("EXECUTING begline.\n");
4456 if (AT_STRINGS_BEG (d)) {
4460 else if (d[-1] == '\n' && bufp->newline_anchor) {
4463 /* In all other cases, we fail. */
4467 /* endline is the dual of begline. */
4469 DEBUG_PRINT1 ("EXECUTING endline.\n");
4471 if (AT_STRINGS_END (d)) {
4476 /* We have to ``prefetch'' the next character. */
4477 else if ((d == end1 ? *string2 : *d) == '\n' && bufp->newline_anchor) {
4483 /* Match at the very beginning of the data. */
4485 DEBUG_PRINT1 ("EXECUTING begbuf.\n");
4486 if (AT_STRINGS_BEG (d))
4491 /* Match at the very end of the data. */
4493 DEBUG_PRINT1 ("EXECUTING endbuf.\n");
4494 if (AT_STRINGS_END (d))
4499 /* on_failure_keep_string_jump is used to optimize `.*\n'. It
4500 pushes NULL as the value for the string on the stack. Then
4501 `pop_failure_point' will keep the current value for the
4502 string, instead of restoring it. To see why, consider
4503 matching `foo\nbar' against `.*\n'. The .* matches the foo;
4504 then the . fails against the \n. But the next thing we want
4505 to do is match the \n against the \n; if we restored the
4506 string value, we would be back at the foo.
4508 Because this is used only in specific cases, we don't need to
4509 check all the things that `on_failure_jump' does, to make
4510 sure the right things get saved on the stack. Hence we don't
4511 share its code. The only reason to push anything on the
4512 stack at all is that otherwise we would have to change
4513 `anychar's code to do something besides goto fail in this
4514 case; that seems worse than this. */
4515 case on_failure_keep_string_jump:
4516 DEBUG_PRINT1 ("EXECUTING on_failure_keep_string_jump");
4518 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4520 DEBUG_PRINT3 (" %d (to %p):\n", mcnt, p + mcnt);
4522 DEBUG_PRINT3 (" %d (to 0x%x):\n", mcnt, p + mcnt);
4525 PUSH_FAILURE_POINT (p + mcnt, NULL, -2);
4529 /* Uses of on_failure_jump:
4531 Each alternative starts with an on_failure_jump that points
4532 to the beginning of the next alternative. Each alternative
4533 except the last ends with a jump that in effect jumps past
4534 the rest of the alternatives. (They really jump to the
4535 ending jump of the following alternative, because tensioning
4536 these jumps is a hassle.)
4538 Repeats start with an on_failure_jump that points past both
4539 the repetition text and either the following jump or
4540 pop_failure_jump back to this on_failure_jump. */
4541 case on_failure_jump:
4543 DEBUG_PRINT1 ("EXECUTING on_failure_jump");
4545 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4547 DEBUG_PRINT3 (" %d (to %p)", mcnt, p + mcnt);
4549 DEBUG_PRINT3 (" %d (to 0x%x)", mcnt, p + mcnt);
4552 /* If this on_failure_jump comes right before a group (i.e.,
4553 the original * applied to a group), save the information
4554 for that group and all inner ones, so that if we fail back
4555 to this point, the group's information will be correct.
4556 For example, in \(a*\)*\1, we need the preceding group,
4557 and in \(zz\(a*\)b*\)\2, we need the inner group. */
4559 /* We can't use `p' to check ahead because we push
4560 a failure point to `p + mcnt' after we do this. */
4563 /* We need to skip no_op's before we look for the
4564 start_memory in case this on_failure_jump is happening as
4565 the result of a completed succeed_n, as in \(a\)\{1,3\}b\1
4567 while (p1 < pend && (re_opcode_t) * p1 == no_op)
4570 if (p1 < pend && (re_opcode_t) * p1 == start_memory) {
4571 /* We have a new highest active register now. This will
4572 get reset at the start_memory we are about to get to,
4573 but we will have saved all the registers relevant to
4574 this repetition op, as described above. */
4575 highest_active_reg = *(p1 + 1) + *(p1 + 2);
4576 if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
4577 lowest_active_reg = *(p1 + 1);
4580 DEBUG_PRINT1 (":\n");
4581 PUSH_FAILURE_POINT (p + mcnt, d, -2);
4585 /* A smart repeat ends with `maybe_pop_jump'.
4586 We change it to either `pop_failure_jump' or `jump'. */
4587 case maybe_pop_jump:
4588 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4589 DEBUG_PRINT2 ("EXECUTING maybe_pop_jump %d.\n", mcnt);
4591 register unsigned char *p2 = p;
4593 /* Compare the beginning of the repeat with what in the
4594 pattern follows its end. If we can establish that there
4595 is nothing that they would both match, i.e., that we
4596 would have to backtrack because of (as in, e.g., `a*a')
4597 then we can change to pop_failure_jump, because we'll
4598 never have to backtrack.
4600 This is not true in the case of alternatives: in
4601 `(a|ab)*' we do need to backtrack to the `ab' alternative
4602 (e.g., if the string was `ab'). But instead of trying to
4603 detect that here, the alternative has put on a dummy
4604 failure point which is what we will end up popping. */
4606 /* Skip over open/close-group commands.
4607 If what follows this loop is a ...+ construct,
4608 look at what begins its body, since we will have to
4609 match at least one of that. */
4612 && ((re_opcode_t) * p2 == stop_memory
4613 || (re_opcode_t) * p2 == start_memory))
4615 else if (p2 + 6 < pend && (re_opcode_t) * p2 == dummy_failure_jump)
4622 /* p1[0] ... p1[2] are the `on_failure_jump' corresponding
4623 to the `maybe_finalize_jump' of this case. Examine what
4626 /* If we're at the end of the pattern, we can change. */
4628 /* Consider what happens when matching ":\(.*\)"
4629 against ":/". I don't really understand this code
4631 p[-3] = (unsigned char) pop_failure_jump;
4632 DEBUG_PRINT1 (" End of pattern: change to `pop_failure_jump'.\n");
4635 else if ((re_opcode_t) * p2 == exactn
4636 || (bufp->newline_anchor && (re_opcode_t) * p2 == endline)) {
4637 register unsigned char c
4638 = *p2 == (unsigned char) endline ? '\n' : p2[2];
4640 if ((re_opcode_t) p1[3] == exactn && p1[5] != c) {
4641 p[-3] = (unsigned char) pop_failure_jump;
4642 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n", c, p1[5]);
4645 else if ((re_opcode_t) p1[3] == charset
4646 || (re_opcode_t) p1[3] == charset_not) {
4647 int not = (re_opcode_t) p1[3] == charset_not;
4649 if (c < (unsigned char) (p1[4] * BYTEWIDTH)
4650 && p1[5 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4653 /* `not' is equal to 1 if c would match, which means
4654 that we can't change to pop_failure_jump. */
4656 p[-3] = (unsigned char) pop_failure_jump;
4657 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4661 else if ((re_opcode_t) * p2 == charset) {
4663 register unsigned char c
4664 = *p2 == (unsigned char) endline ? '\n' : p2[2];
4668 if ((re_opcode_t) p1[3] == exactn
4669 && !((int) p2[1] * BYTEWIDTH > (int) p1[5]
4670 && (p2[2 + p1[5] / BYTEWIDTH]
4671 & (1 << (p1[5] % BYTEWIDTH)))))
4673 if ((re_opcode_t) p1[3] == exactn
4674 && !((int) p2[1] * BYTEWIDTH > (int) p1[4]
4675 && (p2[2 + p1[4] / BYTEWIDTH]
4676 & (1 << (p1[4] % BYTEWIDTH)))))
4679 p[-3] = (unsigned char) pop_failure_jump;
4680 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n", c, p1[5]);
4683 else if ((re_opcode_t) p1[3] == charset_not) {
4686 /* We win if the charset_not inside the loop
4687 lists every character listed in the charset after. */
4688 for (idx = 0; idx < (int) p2[1]; idx++)
4689 if (!(p2[2 + idx] == 0 || (idx < (int) p1[4]
4690 && ((p2[2 + idx] & ~p1[5 + idx]) ==
4695 p[-3] = (unsigned char) pop_failure_jump;
4696 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4699 else if ((re_opcode_t) p1[3] == charset) {
4702 /* We win if the charset inside the loop
4703 has no overlap with the one after the loop. */
4704 for (idx = 0; idx < (int) p2[1] && idx < (int) p1[4]; idx++)
4705 if ((p2[2 + idx] & p1[5 + idx]) != 0)
4708 if (idx == p2[1] || idx == p1[4]) {
4709 p[-3] = (unsigned char) pop_failure_jump;
4710 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4715 p -= 2; /* Point at relative address again. */
4716 if ((re_opcode_t) p[-1] != pop_failure_jump) {
4717 p[-1] = (unsigned char) jump;
4718 DEBUG_PRINT1 (" Match => jump.\n");
4719 goto unconditional_jump;
4721 /* Note fall through. */
4724 /* The end of a simple repeat has a pop_failure_jump back to
4725 its matching on_failure_jump, where the latter will push a
4726 failure point. The pop_failure_jump takes off failure
4727 points put on by this pop_failure_jump's matching
4728 on_failure_jump; we got through the pattern to here from the
4729 matching on_failure_jump, so didn't fail. */
4730 case pop_failure_jump:
4732 /* We need to pass separate storage for the lowest and
4733 highest registers, even though we don't care about the
4734 actual values. Otherwise, we will restore only one
4735 register from the stack, since lowest will == highest in
4736 `pop_failure_point'. */
4737 active_reg_t dummy_low_reg, dummy_high_reg;
4738 unsigned char *pdummy;
4741 DEBUG_PRINT1 ("EXECUTING pop_failure_jump.\n");
4742 POP_FAILURE_POINT (sdummy, pdummy,
4743 dummy_low_reg, dummy_high_reg,
4744 reg_dummy, reg_dummy, reg_info_dummy);
4746 /* Note fall through. */
4750 DEBUG_PRINT2 ("\n%p: ", p);
4752 DEBUG_PRINT2 ("\n0x%x: ", p);
4754 /* Note fall through. */
4756 /* Unconditionally jump (without popping any failure points). */
4758 EXTRACT_NUMBER_AND_INCR (mcnt, p); /* Get the amount to jump. */
4759 DEBUG_PRINT2 ("EXECUTING jump %d ", mcnt);
4760 p += mcnt; /* Do the jump. */
4762 DEBUG_PRINT2 ("(to %p).\n", p);
4764 DEBUG_PRINT2 ("(to 0x%x).\n", p);
4769 /* We need this opcode so we can detect where alternatives end
4770 in `group_match_null_string_p' et al. */
4772 DEBUG_PRINT1 ("EXECUTING jump_past_alt.\n");
4773 goto unconditional_jump;
4776 /* Normally, the on_failure_jump pushes a failure point, which
4777 then gets popped at pop_failure_jump. We will end up at
4778 pop_failure_jump, also, and with a pattern of, say, `a+', we
4779 are skipping over the on_failure_jump, so we have to push
4780 something meaningless for pop_failure_jump to pop. */
4781 case dummy_failure_jump:
4782 DEBUG_PRINT1 ("EXECUTING dummy_failure_jump.\n");
4783 /* It doesn't matter what we push for the string here. What
4784 the code at `fail' tests is the value for the pattern. */
4785 PUSH_FAILURE_POINT (0, 0, -2);
4786 goto unconditional_jump;
4789 /* At the end of an alternative, we need to push a dummy failure
4790 point in case we are followed by a `pop_failure_jump', because
4791 we don't want the failure point for the alternative to be
4792 popped. For example, matching `(a|ab)*' against `aab'
4793 requires that we match the `ab' alternative. */
4794 case push_dummy_failure:
4795 DEBUG_PRINT1 ("EXECUTING push_dummy_failure.\n");
4796 /* See comments just above at `dummy_failure_jump' about the
4798 PUSH_FAILURE_POINT (0, 0, -2);
4801 /* Have to succeed matching what follows at least n times.
4802 After that, handle like `on_failure_jump'. */
4804 EXTRACT_NUMBER (mcnt, p + 2);
4805 DEBUG_PRINT2 ("EXECUTING succeed_n %d.\n", mcnt);
4808 /* Originally, this is how many times we HAVE to succeed. */
4812 STORE_NUMBER_AND_INCR (p, mcnt);
4814 DEBUG_PRINT3 (" Setting %p to %d.\n", p - 2, mcnt);
4816 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p - 2, mcnt);
4819 else if (mcnt == 0) {
4821 DEBUG_PRINT2 (" Setting two bytes from %p to no_op.\n", p + 2);
4823 DEBUG_PRINT2 (" Setting two bytes from 0x%x to no_op.\n", p + 2);
4825 p[2] = (unsigned char) no_op;
4826 p[3] = (unsigned char) no_op;
4832 EXTRACT_NUMBER (mcnt, p + 2);
4833 DEBUG_PRINT2 ("EXECUTING jump_n %d.\n", mcnt);
4835 /* Originally, this is how many times we CAN jump. */
4838 STORE_NUMBER (p + 2, mcnt);
4840 DEBUG_PRINT3 (" Setting %p to %d.\n", p + 2, mcnt);
4842 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p + 2, mcnt);
4844 goto unconditional_jump;
4846 /* If don't have to jump any more, skip over the rest of command. */
4853 DEBUG_PRINT1 ("EXECUTING set_number_at.\n");
4855 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4857 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4859 DEBUG_PRINT3 (" Setting %p to %d.\n", p1, mcnt);
4861 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p1, mcnt);
4863 STORE_NUMBER (p1, mcnt);
4868 /* The DEC Alpha C compiler 3.x generates incorrect code for the
4869 test WORDCHAR_P (d - 1) != WORDCHAR_P (d) in the expansion of
4870 AT_WORD_BOUNDARY, so this code is disabled. Expanding the
4871 macro and introducing temporary variables works around the bug. */
4874 DEBUG_PRINT1 ("EXECUTING wordbound.\n");
4875 if (AT_WORD_BOUNDARY (d))
4880 DEBUG_PRINT1 ("EXECUTING notwordbound.\n");
4881 if (AT_WORD_BOUNDARY (d))
4887 boolean prevchar, thischar;
4889 DEBUG_PRINT1 ("EXECUTING wordbound.\n");
4890 if (AT_STRINGS_BEG (d) || AT_STRINGS_END (d))
4893 prevchar = WORDCHAR_P (d - 1);
4894 thischar = WORDCHAR_P (d);
4895 if (prevchar != thischar)
4902 boolean prevchar, thischar;
4904 DEBUG_PRINT1 ("EXECUTING notwordbound.\n");
4905 if (AT_STRINGS_BEG (d) || AT_STRINGS_END (d))
4908 prevchar = WORDCHAR_P (d - 1);
4909 thischar = WORDCHAR_P (d);
4910 if (prevchar != thischar)
4917 DEBUG_PRINT1 ("EXECUTING wordbeg.\n");
4918 if (WORDCHAR_P (d) && (AT_STRINGS_BEG (d) || !WORDCHAR_P (d - 1)))
4923 DEBUG_PRINT1 ("EXECUTING wordend.\n");
4924 if (!AT_STRINGS_BEG (d) && WORDCHAR_P (d - 1)
4925 && (!WORDCHAR_P (d) || AT_STRINGS_END (d)))
4931 DEBUG_PRINT1 ("EXECUTING before_dot.\n");
4932 if (PTR_CHAR_POS ((unsigned char *) d) >= point)
4937 DEBUG_PRINT1 ("EXECUTING at_dot.\n");
4938 if (PTR_CHAR_POS ((unsigned char *) d) != point)
4943 DEBUG_PRINT1 ("EXECUTING after_dot.\n");
4944 if (PTR_CHAR_POS ((unsigned char *) d) <= point)
4949 DEBUG_PRINT2 ("EXECUTING syntaxspec %d.\n", mcnt);
4954 DEBUG_PRINT1 ("EXECUTING Emacs wordchar.\n");
4958 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
4960 if (SYNTAX (d[-1]) != (enum syntaxcode) mcnt)
4962 SET_REGS_MATCHED ();
4966 DEBUG_PRINT2 ("EXECUTING notsyntaxspec %d.\n", mcnt);
4968 goto matchnotsyntax;
4971 DEBUG_PRINT1 ("EXECUTING Emacs notwordchar.\n");
4975 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
4977 if (SYNTAX (d[-1]) == (enum syntaxcode) mcnt)
4979 SET_REGS_MATCHED ();
4982 #else /* not emacs */
4984 DEBUG_PRINT1 ("EXECUTING non-Emacs wordchar.\n");
4986 if (!WORDCHAR_P (d))
4988 SET_REGS_MATCHED ();
4993 DEBUG_PRINT1 ("EXECUTING non-Emacs notwordchar.\n");
4997 SET_REGS_MATCHED ();
5000 #endif /* not emacs */
5005 continue; /* Successfully executed one pattern command; keep going. */
5008 /* We goto here if a matching operation fails. */
5010 if (!FAIL_STACK_EMPTY ()) { /* A restart point is known. Restore to that state. */
5011 DEBUG_PRINT1 ("\nFAIL:\n");
5012 POP_FAILURE_POINT (d, p,
5013 lowest_active_reg, highest_active_reg,
5014 regstart, regend, reg_info);
5016 /* If this failure point is a dummy, try the next one. */
5020 /* If we failed to the end of the pattern, don't examine *p. */
5023 boolean is_a_jump_n = false;
5025 /* If failed to a backwards jump that's part of a repetition
5026 loop, need to pop this failure point and use the next one. */
5027 switch ((re_opcode_t) * p) {
5030 case maybe_pop_jump:
5031 case pop_failure_jump:
5034 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5037 if ((is_a_jump_n && (re_opcode_t) * p1 == succeed_n)
5038 || (!is_a_jump_n && (re_opcode_t) * p1 == on_failure_jump))
5046 if (d >= string1 && d <= end1)
5050 break; /* Matching at this starting point really fails. */
5054 goto restore_best_regs;
5058 return -1; /* Failure to match. */
5061 /* Subroutine definitions for re_match_2. */
5064 /* We are passed P pointing to a register number after a start_memory.
5066 Return true if the pattern up to the corresponding stop_memory can
5067 match the empty string, and false otherwise.
5069 If we find the matching stop_memory, sets P to point to one past its number.
5070 Otherwise, sets P to an undefined byte less than or equal to END.
5072 We don't handle duplicates properly (yet). */
5074 static boolean group_match_null_string_p (p, end, reg_info)
5075 unsigned char **p, *end;
5076 register_info_type *reg_info;
5080 /* Point to after the args to the start_memory. */
5081 unsigned char *p1 = *p + 2;
5084 /* Skip over opcodes that can match nothing, and return true or
5085 false, as appropriate, when we get to one that can't, or to the
5086 matching stop_memory. */
5088 switch ((re_opcode_t) * p1) {
5089 /* Could be either a loop or a series of alternatives. */
5090 case on_failure_jump:
5092 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5094 /* If the next operation is not a jump backwards in the
5098 /* Go through the on_failure_jumps of the alternatives,
5099 seeing if any of the alternatives cannot match nothing.
5100 The last alternative starts with only a jump,
5101 whereas the rest start with on_failure_jump and end
5102 with a jump, e.g., here is the pattern for `a|b|c':
5104 /on_failure_jump/0/6/exactn/1/a/jump_past_alt/0/6
5105 /on_failure_jump/0/6/exactn/1/b/jump_past_alt/0/3
5108 So, we have to first go through the first (n-1)
5109 alternatives and then deal with the last one separately. */
5112 /* Deal with the first (n-1) alternatives, which start
5113 with an on_failure_jump (see above) that jumps to right
5114 past a jump_past_alt. */
5116 while ((re_opcode_t) p1[mcnt - 3] == jump_past_alt) {
5117 /* `mcnt' holds how many bytes long the alternative
5118 is, including the ending `jump_past_alt' and
5121 if (!alt_match_null_string_p (p1, p1 + mcnt - 3, reg_info))
5124 /* Move to right after this alternative, including the
5128 /* Break if it's the beginning of an n-th alternative
5129 that doesn't begin with an on_failure_jump. */
5130 if ((re_opcode_t) * p1 != on_failure_jump)
5133 /* Still have to check that it's not an n-th
5134 alternative that starts with an on_failure_jump. */
5136 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5137 if ((re_opcode_t) p1[mcnt - 3] != jump_past_alt) {
5138 /* Get to the beginning of the n-th alternative. */
5144 /* Deal with the last alternative: go back and get number
5145 of the `jump_past_alt' just before it. `mcnt' contains
5146 the length of the alternative. */
5147 EXTRACT_NUMBER (mcnt, p1 - 2);
5149 if (!alt_match_null_string_p (p1, p1 + mcnt, reg_info))
5152 p1 += mcnt; /* Get past the n-th alternative. */
5158 assert (p1[1] == **p);
5164 if (!common_op_match_null_string_p (&p1, end, reg_info))
5167 } /* while p1 < end */
5170 } /* group_match_null_string_p */
5173 /* Similar to group_match_null_string_p, but doesn't deal with alternatives:
5174 It expects P to be the first byte of a single alternative and END one
5175 byte past the last. The alternative can contain groups. */
5177 static boolean alt_match_null_string_p (p, end, reg_info)
5178 unsigned char *p, *end;
5179 register_info_type *reg_info;
5182 unsigned char *p1 = p;
5185 /* Skip over opcodes that can match nothing, and break when we get
5186 to one that can't. */
5188 switch ((re_opcode_t) * p1) {
5190 case on_failure_jump:
5192 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5197 if (!common_op_match_null_string_p (&p1, end, reg_info))
5200 } /* while p1 < end */
5203 } /* alt_match_null_string_p */
5206 /* Deals with the ops common to group_match_null_string_p and
5207 alt_match_null_string_p.
5209 Sets P to one after the op and its arguments, if any. */
5211 static boolean common_op_match_null_string_p (p, end, reg_info)
5212 unsigned char **p, *end;
5213 register_info_type *reg_info;
5218 unsigned char *p1 = *p;
5220 switch ((re_opcode_t) * p1++) {
5239 assert (reg_no > 0 && reg_no <= MAX_REGNUM);
5240 ret = group_match_null_string_p (&p1, end, reg_info);
5242 /* Have to set this here in case we're checking a group which
5243 contains a group and a back reference to it. */
5245 if (REG_MATCH_NULL_STRING_P (reg_info[reg_no]) == MATCH_NULL_UNSET_VALUE)
5246 REG_MATCH_NULL_STRING_P (reg_info[reg_no]) = ret;
5252 /* If this is an optimized succeed_n for zero times, make the jump. */
5254 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5262 /* Get to the number of times to succeed. */
5264 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5268 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5276 if (!REG_MATCH_NULL_STRING_P (reg_info[*p1]))
5284 /* All other opcodes mean we cannot match the empty string. */
5290 } /* common_op_match_null_string_p */
5293 /* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
5294 bytes; nonzero otherwise. */
5296 static int bcmp_translate (s1, s2, len, translate)
5297 const char *s1, *s2;
5299 RE_TRANSLATE_TYPE translate;
5301 register const unsigned char *p1 = (const unsigned char *) s1;
5302 register const unsigned char *p2 = (const unsigned char *) s2;
5305 if (translate[*p1++] != translate[*p2++])
5312 /* Entry points for GNU code. */
5314 /* re_compile_pattern is the GNU regular expression compiler: it
5315 compiles PATTERN (of length SIZE) and puts the result in BUFP.
5316 Returns 0 if the pattern was valid, otherwise an error string.
5318 Assumes the `allocated' (and perhaps `buffer') and `translate' fields
5319 are set in BUFP on entry.
5321 We call regex_compile to do the actual compilation. */
5323 const char *re_compile_pattern (pattern, length, bufp)
5324 const char *pattern;
5326 struct re_pattern_buffer *bufp;
5330 /* GNU code is written to assume at least RE_NREGS registers will be set
5331 (and at least one extra will be -1). */
5332 bufp->regs_allocated = REGS_UNALLOCATED;
5334 /* And GNU code determines whether or not to get register information
5335 by passing null for the REGS argument to re_match, etc., not by
5339 /* Match anchors at newline. */
5340 bufp->newline_anchor = 1;
5342 ret = regex_compile (pattern, length, re_syntax_options, bufp);
5346 return gettext (re_error_msgid[(int) ret]);
5349 /* Entry points compatible with 4.2 BSD regex library. We don't define
5350 them unless specifically requested. */
5352 #if defined (_REGEX_RE_COMP) || defined (_LIBC)
5354 /* BSD has one and only one pattern buffer. */
5355 static struct re_pattern_buffer re_comp_buf;
5359 /* Make these definitions weak in libc, so POSIX programs can redefine
5360 these names if they don't use our functions, and still use
5361 regcomp/regexec below without link errors. */
5370 if (!re_comp_buf.buffer)
5371 return gettext ("No previous regular expression");
5375 if (!re_comp_buf.buffer) {
5376 re_comp_buf.buffer = (unsigned char *) malloc (200); /* __MEM_CHECKED__ */
5377 if (re_comp_buf.buffer == NULL)
5378 return gettext (re_error_msgid[(int) REG_ESPACE]);
5379 re_comp_buf.allocated = 200;
5381 re_comp_buf.fastmap = (char *) malloc (1 << BYTEWIDTH); /* __MEM_CHECKED__ */
5382 if (re_comp_buf.fastmap == NULL)
5383 return gettext (re_error_msgid[(int) REG_ESPACE]);
5386 /* Since `re_exec' always passes NULL for the `regs' argument, we
5387 don't need to initialize the pattern buffer fields which affect it. */
5389 /* Match anchors at newlines. */
5390 re_comp_buf.newline_anchor = 1;
5392 ret = regex_compile (s, mutt_strlen (s), re_syntax_options, &re_comp_buf);
5397 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
5398 return (char *) gettext (re_error_msgid[(int) ret]);
5409 const int len = mutt_strlen (s);
5412 0 <= re_search (&re_comp_buf, s, len, 0, len, (struct re_registers *) 0);
5415 #endif /* _REGEX_RE_COMP */
5417 /* POSIX.2 functions. Don't define these for Emacs. */
5421 /* regcomp takes a regular expression as a string and compiles it.
5423 PREG is a regex_t *. We do not expect any fields to be initialized,
5424 since POSIX says we shouldn't. Thus, we set
5426 `buffer' to the compiled pattern;
5427 `used' to the length of the compiled pattern;
5428 `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
5429 REG_EXTENDED bit in CFLAGS is set; otherwise, to
5430 RE_SYNTAX_POSIX_BASIC;
5431 `newline_anchor' to REG_NEWLINE being set in CFLAGS;
5432 `fastmap' and `fastmap_accurate' to zero;
5433 `re_nsub' to the number of subexpressions in PATTERN.
5435 PATTERN is the address of the pattern string.
5437 CFLAGS is a series of bits which affect compilation.
5439 If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
5440 use POSIX basic syntax.
5442 If REG_NEWLINE is set, then . and [^...] don't match newline.
5443 Also, regexec will try a match beginning after every newline.
5445 If REG_ICASE is set, then we considers upper- and lowercase
5446 versions of letters to be equivalent when matching.
5448 If REG_NOSUB is set, then when PREG is passed to regexec, that
5449 routine will report only success or failure, and nothing about the
5452 It returns 0 if it succeeds, nonzero if it doesn't. (See regex.h for
5453 the return codes and their meanings.) */
5455 int regcomp (preg, pattern, cflags)
5457 const char *pattern;
5462 = (cflags & REG_EXTENDED) ?
5463 RE_SYNTAX_POSIX_EXTENDED : RE_SYNTAX_POSIX_BASIC;
5465 /* regex_compile will allocate the space for the compiled pattern. */
5467 preg->allocated = 0;
5470 /* Don't bother to use a fastmap when searching. This simplifies the
5471 REG_NEWLINE case: if we used a fastmap, we'd have to put all the
5472 characters after newlines into the fastmap. This way, we just try
5476 if (cflags & REG_ICASE) {
5479 preg->translate = (RE_TRANSLATE_TYPE) malloc (CHAR_SET_SIZE /* __MEM_CHECKED__ */
5481 sizeof (*(RE_TRANSLATE_TYPE)
5483 if (preg->translate == NULL)
5484 return (int) REG_ESPACE;
5486 /* Map uppercase characters to corresponding lowercase ones. */
5487 for (i = 0; i < CHAR_SET_SIZE; i++)
5488 preg->translate[i] = ISUPPER (i) ? tolower (i) : i;
5491 preg->translate = NULL;
5493 /* If REG_NEWLINE is set, newlines are treated differently. */
5494 if (cflags & REG_NEWLINE) { /* REG_NEWLINE implies neither . nor [^...] match newline. */
5495 syntax &= ~RE_DOT_NEWLINE;
5496 syntax |= RE_HAT_LISTS_NOT_NEWLINE;
5497 /* It also changes the matching behavior. */
5498 preg->newline_anchor = 1;
5501 preg->newline_anchor = 0;
5503 preg->no_sub = !!(cflags & REG_NOSUB);
5505 /* POSIX says a null character in the pattern terminates it, so we
5506 can use mutt_strlen here in compiling the pattern. */
5507 ret = regex_compile (pattern, mutt_strlen (pattern), syntax, preg);
5509 /* POSIX doesn't distinguish between an unmatched open-group and an
5510 unmatched close-group: both are REG_EPAREN. */
5511 if (ret == REG_ERPAREN)
5518 /* regexec searches for a given pattern, specified by PREG, in the
5521 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
5522 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
5523 least NMATCH elements, and we set them to the offsets of the
5524 corresponding matched substrings.
5526 EFLAGS specifies `execution flags' which affect matching: if
5527 REG_NOTBOL is set, then ^ does not match at the beginning of the
5528 string; if REG_NOTEOL is set, then $ does not match at the end.
5530 We return 0 if we find a match and REG_NOMATCH if not. */
5532 int regexec (preg, string, nmatch, pmatch, eflags)
5533 const regex_t *preg;
5536 regmatch_t pmatch[];
5540 struct re_registers regs;
5541 regex_t private_preg;
5542 int len = mutt_strlen (string);
5543 boolean want_reg_info = !preg->no_sub && nmatch > 0;
5545 private_preg = *preg;
5547 private_preg.not_bol = !!(eflags & REG_NOTBOL);
5548 private_preg.not_eol = !!(eflags & REG_NOTEOL);
5550 /* The user has told us exactly how many registers to return
5551 information about, via `nmatch'. We have to pass that on to the
5552 matching routines. */
5553 private_preg.regs_allocated = REGS_FIXED;
5555 if (want_reg_info) {
5556 regs.num_regs = nmatch;
5557 regs.start = TALLOC (nmatch, regoff_t);
5558 regs.end = TALLOC (nmatch, regoff_t);
5559 if (regs.start == NULL || regs.end == NULL)
5560 return (int) REG_NOMATCH;
5563 /* Perform the searching operation. */
5564 ret = re_search (&private_preg, string, len,
5565 /* start: */ 0, /* range: */ len,
5566 want_reg_info ? ®s : (struct re_registers *) 0);
5568 /* Copy the register information to the POSIX structure. */
5569 if (want_reg_info) {
5573 for (r = 0; r < nmatch; r++) {
5574 pmatch[r].rm_so = regs.start[r];
5575 pmatch[r].rm_eo = regs.end[r];
5579 /* If we needed the temporary register info, free the space now. */
5580 free (regs.start); /* __MEM_CHECKED__ */
5581 free (regs.end); /* __MEM_CHECKED__ */
5584 /* We want zero return to mean success, unlike `re_search'. */
5585 return ret >= 0 ? (int) REG_NOERROR : (int) REG_NOMATCH;
5589 /* Returns a message corresponding to an error code, ERRCODE, returned
5590 from either regcomp or regexec. We don't use PREG here. */
5592 size_t regerror (errcode, preg, errbuf, errbuf_size)
5594 const regex_t *preg;
5601 if (errcode < 0 || errcode >= (int) (sizeof (re_error_msgid)
5602 / sizeof (re_error_msgid[0])))
5603 /* Only error codes returned by the rest of the code should be passed
5604 to this routine. If we are given anything else, or if other regex
5605 code generates an invalid error code, then the program has a bug.
5606 Dump core so we can fix it. */
5609 msg = gettext (re_error_msgid[errcode]);
5611 msg_size = mutt_strlen (msg) + 1; /* Includes the null. */
5613 if (errbuf_size != 0) {
5614 if (msg_size > errbuf_size) {
5615 strncpy (errbuf, msg, errbuf_size - 1);
5616 errbuf[errbuf_size - 1] = 0;
5619 strcpy (errbuf, msg); /* __STRCPY_CHECKED__ */
5626 /* Free dynamically allocated space used by PREG. */
5631 if (preg->buffer != NULL)
5632 free (preg->buffer); /* __MEM_CHECKED__ */
5633 preg->buffer = NULL;
5635 preg->allocated = 0;
5638 if (preg->fastmap != NULL)
5639 free (preg->fastmap); /* __MEM_CHECKED__ */
5640 preg->fastmap = NULL;
5641 preg->fastmap_accurate = 0;
5643 if (preg->translate != NULL)
5644 free (preg->translate); /* __MEM_CHECKED__ */
5645 preg->translate = NULL;
5648 #endif /* not emacs */