1 /* Extended regular expression matching and search library,
3 (Implements POSIX draft P1003.2/D11.2, except for some of the
4 internationalization features.)
5 Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998
6 Free Software Foundation, Inc.
8 NOTE: The canonical source of this file is maintained with the
9 GNU C Library. Bugs can be reported to bug-glibc@prep.ai.mit.edu.
11 This program is free software; you can redistribute it and/or modify it
12 under the terms of the GNU General Public License as published by the
13 Free Software Foundation; either version 2, or (at your option) any
16 This program 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
19 GNU General Public License for more details.
21 You should have received a copy of the GNU General Public License
22 along with this program; if not, write to the Free Software Foundation,
23 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
32 /* GCC LOCAL: we don't need NLS here. */
34 /* GCC LOCAL: to handle defining alloca. */
35 #include "libiberty.h"
37 /* Do not use a C alloca, we will leak memory and crash. */
42 /* AIX requires this to be the first thing in the file. */
43 #if defined _AIX && !defined REGEX_MALLOC
48 # if defined __GNUC__ || (defined __STDC__ && __STDC__)
49 # define PARAMS(args) args
51 # define PARAMS(args) ()
53 #endif /* Not PARAMS. */
55 #if defined STDC_HEADERS && !defined emacs
58 /* We need this for `gnu-regex.h', and perhaps for the Emacs include files. */
59 # include <sys/types.h>
62 /* For platform which support the ISO C amendement 1 functionality we
63 support user defined character classes. */
64 #if defined _LIBC || (defined HAVE_WCTYPE_H && defined HAVE_WCHAR_H)
65 /* Solaris 2.5 has a bug: <wchar.h> must be included before <wctype.h>. */
70 /* This is for other GNU distributions with internationalized messages. */
71 /* GCC LOCAL: ../intl will handle this for us */
75 # define gettext(msgid) (msgid)
79 /* This define is so xgettext can find the internationalizable
81 # define gettext_noop(String) String
84 # if !defined(volatile) && !defined(HAVE_VOLATILE)
88 /* If we are not linking with Emacs proper,
89 we can't use the relocating allocator
90 even if config.h says that we can. */
93 # if defined STDC_HEADERS || defined _LIBC
100 /* When used in Emacs's lib-src, we need to get bzero and bcopy somehow.
101 If nothing else has been done, use the method below. */
102 # ifdef INHIBIT_STRING_HEADER
103 # if !(defined HAVE_BZERO && defined HAVE_BCOPY)
104 # if !defined bzero && !defined bcopy
105 # undef INHIBIT_STRING_HEADER
110 /* This is the normal way of making sure we have a bcopy and a bzero.
111 This is used in most programs--a few other programs avoid this
112 by defining INHIBIT_STRING_HEADER. */
113 # ifndef INHIBIT_STRING_HEADER
114 # if defined HAVE_STRING_H || defined STDC_HEADERS || defined _LIBC
118 # define bzero(s, n) (memset (s, '\0', n), (s))
120 # define bzero(s, n) __bzero (s, n)
124 # include <strings.h>
126 # define memcmp(s1, s2, n) bcmp (s1, s2, n)
129 # define memcpy(d, s, n) (bcopy (s, d, n), (d))
134 /* Define the syntax stuff for \<, \>, etc. */
136 /* This must be nonzero for the wordchar and notwordchar pattern
137 commands in re_match_2. */
142 # ifdef SWITCH_ENUM_BUG
143 # define SWITCH_ENUM_CAST(x) ((int)(x))
145 # define SWITCH_ENUM_CAST(x) (x)
148 /* How many characters in the character set. */
149 # define CHAR_SET_SIZE 256
153 extern char *re_syntax_table;
155 # else /* not SYNTAX_TABLE */
157 static char re_syntax_table[CHAR_SET_SIZE];
168 bzero (re_syntax_table, sizeof re_syntax_table);
170 for (c = 'a'; c <= 'z'; c++)
171 re_syntax_table[c] = Sword;
173 for (c = 'A'; c <= 'Z'; c++)
174 re_syntax_table[c] = Sword;
176 for (c = '0'; c <= '9'; c++)
177 re_syntax_table[c] = Sword;
179 re_syntax_table['_'] = Sword;
184 # endif /* not SYNTAX_TABLE */
186 # define SYNTAX(c) re_syntax_table[c]
188 /* Get the interface, including the syntax bits. */
189 /* GCC LOCAL: call it gnu-regex.h, not regex.h, to avoid name conflicts */
190 #include "gnu-regex.h"
192 /* ISALPHA etc. are used for the character classes. */
193 /* GCC LOCAL: use libiberty's safe-ctype.h, don't bother defining
194 wrapper macros ourselves. */
195 #include <safe-ctype.h>
198 # define NULL (void *)0
201 /* We remove any previous definition of `SIGN_EXTEND_CHAR',
202 since ours (we hope) works properly with all combinations of
203 machines, compilers, `char' and `unsigned char' argument types.
204 (Per Bothner suggested the basic approach.) */
205 #undef SIGN_EXTEND_CHAR
207 # define SIGN_EXTEND_CHAR(c) ((signed char) (c))
208 #else /* not __STDC__ */
209 /* As in Harbison and Steele. */
210 # define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128)
213 /* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we
214 use `alloca' instead of `malloc'. This is because using malloc in
215 re_search* or re_match* could cause memory leaks when C-g is used in
216 Emacs; also, malloc is slower and causes storage fragmentation. On
217 the other hand, malloc is more portable, and easier to debug.
219 Because we sometimes use alloca, some routines have to be macros,
220 not functions -- `alloca'-allocated space disappears at the end of the
221 function it is called in. */
225 # define REGEX_ALLOCATE malloc
226 # define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
227 # define REGEX_FREE free
229 #else /* not REGEX_MALLOC */
231 /* Emacs already defines alloca, sometimes. */
234 /* Make alloca work the best possible way. */
236 # define alloca __builtin_alloca
237 # else /* not __GNUC__ */
240 # endif /* HAVE_ALLOCA_H */
241 # endif /* not __GNUC__ */
243 # endif /* not alloca */
245 # define REGEX_ALLOCATE alloca
247 /* Assumes a `char *destination' variable. */
248 # define REGEX_REALLOCATE(source, osize, nsize) \
249 (destination = (char *) alloca (nsize), \
250 memcpy (destination, source, osize))
252 /* No need to do anything to free, after alloca. */
253 # define REGEX_FREE(arg) ((void)0) /* Do nothing! But inhibit gcc warning. */
255 #endif /* not REGEX_MALLOC */
257 /* Define how to allocate the failure stack. */
259 #if defined REL_ALLOC && defined REGEX_MALLOC
261 # define REGEX_ALLOCATE_STACK(size) \
262 r_alloc (&failure_stack_ptr, (size))
263 # define REGEX_REALLOCATE_STACK(source, osize, nsize) \
264 r_re_alloc (&failure_stack_ptr, (nsize))
265 # define REGEX_FREE_STACK(ptr) \
266 r_alloc_free (&failure_stack_ptr)
268 #else /* not using relocating allocator */
272 # define REGEX_ALLOCATE_STACK malloc
273 # define REGEX_REALLOCATE_STACK(source, osize, nsize) realloc (source, nsize)
274 # define REGEX_FREE_STACK free
276 # else /* not REGEX_MALLOC */
278 # define REGEX_ALLOCATE_STACK alloca
280 # define REGEX_REALLOCATE_STACK(source, osize, nsize) \
281 REGEX_REALLOCATE (source, osize, nsize)
282 /* No need to explicitly free anything. */
283 # define REGEX_FREE_STACK(arg)
285 # endif /* not REGEX_MALLOC */
286 #endif /* not using relocating allocator */
289 /* True if `size1' is non-NULL and PTR is pointing anywhere inside
290 `string1' or just past its end. This works if PTR is NULL, which is
292 #define FIRST_STRING_P(ptr) \
293 (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
295 /* (Re)Allocate N items of type T using malloc, or fail. */
296 #define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
297 #define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
298 #define RETALLOC_IF(addr, n, t) \
299 if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
300 #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
302 #define BYTEWIDTH 8 /* In bits. */
304 #define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
308 #define MAX(a, b) ((a) > (b) ? (a) : (b))
309 #define MIN(a, b) ((a) < (b) ? (a) : (b))
311 typedef char boolean;
315 static int re_match_2_internal PARAMS ((struct re_pattern_buffer *bufp,
316 const char *string1, int size1,
317 const char *string2, int size2,
319 struct re_registers *regs,
322 /* These are the command codes that appear in compiled regular
323 expressions. Some opcodes are followed by argument bytes. A
324 command code can specify any interpretation whatsoever for its
325 arguments. Zero bytes may appear in the compiled regular expression. */
331 /* Succeed right away--no more backtracking. */
334 /* Followed by one byte giving n, then by n literal bytes. */
337 /* Matches any (more or less) character. */
340 /* Matches any one char belonging to specified set. First
341 following byte is number of bitmap bytes. Then come bytes
342 for a bitmap saying which chars are in. Bits in each byte
343 are ordered low-bit-first. A character is in the set if its
344 bit is 1. A character too large to have a bit in the map is
345 automatically not in the set. */
348 /* Same parameters as charset, but match any character that is
349 not one of those specified. */
352 /* Start remembering the text that is matched, for storing in a
353 register. Followed by one byte with the register number, in
354 the range 0 to one less than the pattern buffer's re_nsub
355 field. Then followed by one byte with the number of groups
356 inner to this one. (This last has to be part of the
357 start_memory only because we need it in the on_failure_jump
361 /* Stop remembering the text that is matched and store it in a
362 memory register. Followed by one byte with the register
363 number, in the range 0 to one less than `re_nsub' in the
364 pattern buffer, and one byte with the number of inner groups,
365 just like `start_memory'. (We need the number of inner
366 groups here because we don't have any easy way of finding the
367 corresponding start_memory when we're at a stop_memory.) */
370 /* Match a duplicate of something remembered. Followed by one
371 byte containing the register number. */
374 /* Fail unless at beginning of line. */
377 /* Fail unless at end of line. */
380 /* Succeeds if at beginning of buffer (if emacs) or at beginning
381 of string to be matched (if not). */
384 /* Analogously, for end of buffer/string. */
387 /* Followed by two byte relative address to which to jump. */
390 /* Same as jump, but marks the end of an alternative. */
393 /* Followed by two-byte relative address of place to resume at
394 in case of failure. */
397 /* Like on_failure_jump, but pushes a placeholder instead of the
398 current string position when executed. */
399 on_failure_keep_string_jump,
401 /* Throw away latest failure point and then jump to following
402 two-byte relative address. */
405 /* Change to pop_failure_jump if know won't have to backtrack to
406 match; otherwise change to jump. This is used to jump
407 back to the beginning of a repeat. If what follows this jump
408 clearly won't match what the repeat does, such that we can be
409 sure that there is no use backtracking out of repetitions
410 already matched, then we change it to a pop_failure_jump.
411 Followed by two-byte address. */
414 /* Jump to following two-byte address, and push a dummy failure
415 point. This failure point will be thrown away if an attempt
416 is made to use it for a failure. A `+' construct makes this
417 before the first repeat. Also used as an intermediary kind
418 of jump when compiling an alternative. */
421 /* Push a dummy failure point and continue. Used at the end of
425 /* Followed by two-byte relative address and two-byte number n.
426 After matching N times, jump to the address upon failure. */
429 /* Followed by two-byte relative address, and two-byte number n.
430 Jump to the address N times, then fail. */
433 /* Set the following two-byte relative address to the
434 subsequent two-byte number. The address *includes* the two
438 wordchar, /* Matches any word-constituent character. */
439 notwordchar, /* Matches any char that is not a word-constituent. */
441 wordbeg, /* Succeeds if at word beginning. */
442 wordend, /* Succeeds if at word end. */
444 wordbound, /* Succeeds if at a word boundary. */
445 notwordbound /* Succeeds if not at a word boundary. */
448 ,before_dot, /* Succeeds if before point. */
449 at_dot, /* Succeeds if at point. */
450 after_dot, /* Succeeds if after point. */
452 /* Matches any character whose syntax is specified. Followed by
453 a byte which contains a syntax code, e.g., Sword. */
456 /* Matches any character whose syntax is not that specified. */
461 /* Common operations on the compiled pattern. */
463 /* Store NUMBER in two contiguous bytes starting at DESTINATION. */
465 #define STORE_NUMBER(destination, number) \
467 (destination)[0] = (number) & 0377; \
468 (destination)[1] = (number) >> 8; \
471 /* Same as STORE_NUMBER, except increment DESTINATION to
472 the byte after where the number is stored. Therefore, DESTINATION
473 must be an lvalue. */
475 #define STORE_NUMBER_AND_INCR(destination, number) \
477 STORE_NUMBER (destination, number); \
478 (destination) += 2; \
481 /* Put into DESTINATION a number stored in two contiguous bytes starting
484 #define EXTRACT_NUMBER(destination, source) \
486 (destination) = *(source) & 0377; \
487 (destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8; \
491 static void extract_number _RE_ARGS ((int *dest, unsigned char *source));
493 extract_number (dest, source)
495 unsigned char *source;
497 int temp = SIGN_EXTEND_CHAR (*(source + 1));
498 *dest = *source & 0377;
502 # ifndef EXTRACT_MACROS /* To debug the macros. */
503 # undef EXTRACT_NUMBER
504 # define EXTRACT_NUMBER(dest, src) extract_number (&dest, src)
505 # endif /* not EXTRACT_MACROS */
509 /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
510 SOURCE must be an lvalue. */
512 #define EXTRACT_NUMBER_AND_INCR(destination, source) \
514 EXTRACT_NUMBER (destination, source); \
519 static void extract_number_and_incr _RE_ARGS ((int *destination,
520 unsigned char **source));
522 extract_number_and_incr (destination, source)
524 unsigned char **source;
526 extract_number (destination, *source);
530 # ifndef EXTRACT_MACROS
531 # undef EXTRACT_NUMBER_AND_INCR
532 # define EXTRACT_NUMBER_AND_INCR(dest, src) \
533 extract_number_and_incr (&dest, &src)
534 # endif /* not EXTRACT_MACROS */
538 /* If DEBUG is defined, Regex prints many voluminous messages about what
539 it is doing (if the variable `debug' is nonzero). If linked with the
540 main program in `iregex.c', you can enter patterns and strings
541 interactively. And if linked with the main program in `main.c' and
542 the other test files, you can run the already-written tests. */
546 /* We use standard I/O for debugging. */
549 /* It is useful to test things that ``must'' be true when debugging. */
552 static int debug = 0;
554 # define DEBUG_STATEMENT(e) e
555 # define DEBUG_PRINT1(x) if (debug) printf (x)
556 # define DEBUG_PRINT2(x1, x2) if (debug) printf (x1, x2)
557 # define DEBUG_PRINT3(x1, x2, x3) if (debug) printf (x1, x2, x3)
558 # define DEBUG_PRINT4(x1, x2, x3, x4) if (debug) printf (x1, x2, x3, x4)
559 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) \
560 if (debug) print_partial_compiled_pattern (s, e)
561 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) \
562 if (debug) print_double_string (w, s1, sz1, s2, sz2)
565 /* Print the fastmap in human-readable form. */
568 print_fastmap (fastmap)
571 unsigned was_a_range = 0;
574 while (i < (1 << BYTEWIDTH))
580 while (i < (1 << BYTEWIDTH) && fastmap[i])
596 /* Print a compiled pattern string in human-readable form, starting at
597 the START pointer into it and ending just before the pointer END. */
600 print_partial_compiled_pattern (start, end)
601 unsigned char *start;
606 unsigned char *p = start;
607 unsigned char *pend = end;
615 /* Loop over pattern commands. */
618 printf ("%d:\t", p - start);
620 switch ((re_opcode_t) *p++)
628 printf ("/exactn/%d", mcnt);
639 printf ("/start_memory/%d/%d", mcnt, *p++);
644 printf ("/stop_memory/%d/%d", mcnt, *p++);
648 printf ("/duplicate/%d", *p++);
658 register int c, last = -100;
659 register int in_range = 0;
661 printf ("/charset [%s",
662 (re_opcode_t) *(p - 1) == charset_not ? "^" : "");
664 assert (p + *p < pend);
666 for (c = 0; c < 256; c++)
668 && (p[1 + (c/8)] & (1 << (c % 8))))
670 /* Are we starting a range? */
671 if (last + 1 == c && ! in_range)
676 /* Have we broken a range? */
677 else if (last + 1 != c && in_range)
706 case on_failure_jump:
707 extract_number_and_incr (&mcnt, &p);
708 printf ("/on_failure_jump to %d", p + mcnt - start);
711 case on_failure_keep_string_jump:
712 extract_number_and_incr (&mcnt, &p);
713 printf ("/on_failure_keep_string_jump to %d", p + mcnt - start);
716 case dummy_failure_jump:
717 extract_number_and_incr (&mcnt, &p);
718 printf ("/dummy_failure_jump to %d", p + mcnt - start);
721 case push_dummy_failure:
722 printf ("/push_dummy_failure");
726 extract_number_and_incr (&mcnt, &p);
727 printf ("/maybe_pop_jump to %d", p + mcnt - start);
730 case pop_failure_jump:
731 extract_number_and_incr (&mcnt, &p);
732 printf ("/pop_failure_jump to %d", p + mcnt - start);
736 extract_number_and_incr (&mcnt, &p);
737 printf ("/jump_past_alt to %d", p + mcnt - start);
741 extract_number_and_incr (&mcnt, &p);
742 printf ("/jump to %d", p + mcnt - start);
746 extract_number_and_incr (&mcnt, &p);
748 extract_number_and_incr (&mcnt2, &p);
749 printf ("/succeed_n to %d, %d times", p1 - start, mcnt2);
753 extract_number_and_incr (&mcnt, &p);
755 extract_number_and_incr (&mcnt2, &p);
756 printf ("/jump_n to %d, %d times", p1 - start, mcnt2);
760 extract_number_and_incr (&mcnt, &p);
762 extract_number_and_incr (&mcnt2, &p);
763 printf ("/set_number_at location %d to %d", p1 - start, mcnt2);
767 printf ("/wordbound");
771 printf ("/notwordbound");
783 printf ("/before_dot");
791 printf ("/after_dot");
795 printf ("/syntaxspec");
797 printf ("/%d", mcnt);
801 printf ("/notsyntaxspec");
803 printf ("/%d", mcnt);
808 printf ("/wordchar");
812 printf ("/notwordchar");
824 printf ("?%d", *(p-1));
830 printf ("%d:\tend of pattern.\n", p - start);
835 print_compiled_pattern (bufp)
836 struct re_pattern_buffer *bufp;
838 unsigned char *buffer = bufp->buffer;
840 print_partial_compiled_pattern (buffer, buffer + bufp->used);
841 printf ("%ld bytes used/%ld bytes allocated.\n",
842 bufp->used, bufp->allocated);
844 if (bufp->fastmap_accurate && bufp->fastmap)
846 printf ("fastmap: ");
847 print_fastmap (bufp->fastmap);
850 printf ("re_nsub: %d\t", bufp->re_nsub);
851 printf ("regs_alloc: %d\t", bufp->regs_allocated);
852 printf ("can_be_null: %d\t", bufp->can_be_null);
853 printf ("newline_anchor: %d\n", bufp->newline_anchor);
854 printf ("no_sub: %d\t", bufp->no_sub);
855 printf ("not_bol: %d\t", bufp->not_bol);
856 printf ("not_eol: %d\t", bufp->not_eol);
857 printf ("syntax: %lx\n", bufp->syntax);
858 /* Perhaps we should print the translate table? */
863 print_double_string (where, string1, size1, string2, size2)
876 if (FIRST_STRING_P (where))
878 for (this_char = where - string1; this_char < size1; this_char++)
879 putchar (string1[this_char]);
884 for (this_char = where - string2; this_char < size2; this_char++)
885 putchar (string2[this_char]);
896 #else /* not DEBUG */
901 # define DEBUG_STATEMENT(e)
902 # define DEBUG_PRINT1(x)
903 # define DEBUG_PRINT2(x1, x2)
904 # define DEBUG_PRINT3(x1, x2, x3)
905 # define DEBUG_PRINT4(x1, x2, x3, x4)
906 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
907 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
909 #endif /* not DEBUG */
911 /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
912 also be assigned to arbitrarily: each pattern buffer stores its own
913 syntax, so it can be changed between regex compilations. */
914 /* This has no initializer because initialized variables in Emacs
915 become read-only after dumping. */
916 reg_syntax_t re_syntax_options;
919 /* Specify the precise syntax of regexps for compilation. This provides
920 for compatibility for various utilities which historically have
921 different, incompatible syntaxes.
923 The argument SYNTAX is a bit mask comprised of the various bits
924 defined in gnu-regex.h. We return the old syntax. */
927 re_set_syntax (syntax)
930 reg_syntax_t ret = re_syntax_options;
932 re_syntax_options = syntax;
934 if (syntax & RE_DEBUG)
936 else if (debug) /* was on but now is not */
942 weak_alias (__re_set_syntax, re_set_syntax)
945 /* This table gives an error message for each of the error codes listed
946 in gnu-regex.h. Obviously the order here has to be same as there.
947 POSIX doesn't require that we do anything for REG_NOERROR,
948 but why not be nice? */
950 static const char *re_error_msgid[] =
952 gettext_noop ("Success"), /* REG_NOERROR */
953 gettext_noop ("No match"), /* REG_NOMATCH */
954 gettext_noop ("Invalid regular expression"), /* REG_BADPAT */
955 gettext_noop ("Invalid collation character"), /* REG_ECOLLATE */
956 gettext_noop ("Invalid character class name"), /* REG_ECTYPE */
957 gettext_noop ("Trailing backslash"), /* REG_EESCAPE */
958 gettext_noop ("Invalid back reference"), /* REG_ESUBREG */
959 gettext_noop ("Unmatched [ or [^"), /* REG_EBRACK */
960 gettext_noop ("Unmatched ( or \\("), /* REG_EPAREN */
961 gettext_noop ("Unmatched \\{"), /* REG_EBRACE */
962 gettext_noop ("Invalid content of \\{\\}"), /* REG_BADBR */
963 gettext_noop ("Invalid range end"), /* REG_ERANGE */
964 gettext_noop ("Memory exhausted"), /* REG_ESPACE */
965 gettext_noop ("Invalid preceding regular expression"), /* REG_BADRPT */
966 gettext_noop ("Premature end of regular expression"), /* REG_EEND */
967 gettext_noop ("Regular expression too big"), /* REG_ESIZE */
968 gettext_noop ("Unmatched ) or \\)"), /* REG_ERPAREN */
971 /* Avoiding alloca during matching, to placate r_alloc. */
973 /* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
974 searching and matching functions should not call alloca. On some
975 systems, alloca is implemented in terms of malloc, and if we're
976 using the relocating allocator routines, then malloc could cause a
977 relocation, which might (if the strings being searched are in the
978 ralloc heap) shift the data out from underneath the regexp
981 Here's another reason to avoid allocation: Emacs
982 processes input from X in a signal handler; processing X input may
983 call malloc; if input arrives while a matching routine is calling
984 malloc, then we're scrod. But Emacs can't just block input while
985 calling matching routines; then we don't notice interrupts when
986 they come in. So, Emacs blocks input around all regexp calls
987 except the matching calls, which it leaves unprotected, in the
988 faith that they will not malloc. */
990 /* Normally, this is fine. */
991 #define MATCH_MAY_ALLOCATE
993 /* When using GNU C, we are not REALLY using the C alloca, no matter
994 what config.h may say. So don't take precautions for it. */
999 /* The match routines may not allocate if (1) they would do it with malloc
1000 and (2) it's not safe for them to use malloc.
1001 Note that if REL_ALLOC is defined, matching would not use malloc for the
1002 failure stack, but we would still use it for the register vectors;
1003 so REL_ALLOC should not affect this. */
1004 #if (defined C_ALLOCA || defined REGEX_MALLOC) && defined emacs
1005 # undef MATCH_MAY_ALLOCATE
1009 /* Failure stack declarations and macros; both re_compile_fastmap and
1010 re_match_2 use a failure stack. These have to be macros because of
1011 REGEX_ALLOCATE_STACK. */
1014 /* Number of failure points for which to initially allocate space
1015 when matching. If this number is exceeded, we allocate more
1016 space, so it is not a hard limit. */
1017 #ifndef INIT_FAILURE_ALLOC
1018 # define INIT_FAILURE_ALLOC 5
1021 /* Roughly the maximum number of failure points on the stack. Would be
1022 exactly that if always used MAX_FAILURE_ITEMS items each time we failed.
1023 This is a variable only so users of regex can assign to it; we never
1024 change it ourselves. */
1028 # if defined MATCH_MAY_ALLOCATE
1029 /* 4400 was enough to cause a crash on Alpha OSF/1,
1030 whose default stack limit is 2mb. */
1031 long int re_max_failures = 4000;
1033 long int re_max_failures = 2000;
1036 union fail_stack_elt
1038 unsigned char *pointer;
1042 typedef union fail_stack_elt fail_stack_elt_t;
1046 fail_stack_elt_t *stack;
1047 unsigned long int size;
1048 unsigned long int avail; /* Offset of next open position. */
1051 #else /* not INT_IS_16BIT */
1053 # if defined MATCH_MAY_ALLOCATE
1054 /* 4400 was enough to cause a crash on Alpha OSF/1,
1055 whose default stack limit is 2mb. */
1056 int re_max_failures = 20000;
1058 int re_max_failures = 2000;
1061 union fail_stack_elt
1063 unsigned char *pointer;
1067 typedef union fail_stack_elt fail_stack_elt_t;
1071 fail_stack_elt_t *stack;
1073 unsigned avail; /* Offset of next open position. */
1076 #endif /* INT_IS_16BIT */
1078 #define FAIL_STACK_EMPTY() (fail_stack.avail == 0)
1079 #define FAIL_STACK_PTR_EMPTY() (fail_stack_ptr->avail == 0)
1080 #define FAIL_STACK_FULL() (fail_stack.avail == fail_stack.size)
1083 /* Define macros to initialize and free the failure stack.
1084 Do `return -2' if the alloc fails. */
1086 #ifdef MATCH_MAY_ALLOCATE
1087 # define INIT_FAIL_STACK() \
1089 fail_stack.stack = (fail_stack_elt_t *) \
1090 REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * sizeof (fail_stack_elt_t)); \
1092 if (fail_stack.stack == NULL) \
1095 fail_stack.size = INIT_FAILURE_ALLOC; \
1096 fail_stack.avail = 0; \
1099 # define RESET_FAIL_STACK() REGEX_FREE_STACK (fail_stack.stack)
1101 # define INIT_FAIL_STACK() \
1103 fail_stack.avail = 0; \
1106 # define RESET_FAIL_STACK()
1110 /* Double the size of FAIL_STACK, up to approximately `re_max_failures' items.
1112 Return 1 if succeeds, and 0 if either ran out of memory
1113 allocating space for it or it was already too large.
1115 REGEX_REALLOCATE_STACK requires `destination' be declared. */
1117 #define DOUBLE_FAIL_STACK(fail_stack) \
1118 ((fail_stack).size > (unsigned) (re_max_failures * MAX_FAILURE_ITEMS) \
1120 : ((fail_stack).stack = (fail_stack_elt_t *) \
1121 REGEX_REALLOCATE_STACK ((fail_stack).stack, \
1122 (fail_stack).size * sizeof (fail_stack_elt_t), \
1123 ((fail_stack).size << 1) * sizeof (fail_stack_elt_t)), \
1125 (fail_stack).stack == NULL \
1127 : ((fail_stack).size <<= 1, \
1131 /* Push pointer POINTER on FAIL_STACK.
1132 Return 1 if was able to do so and 0 if ran out of memory allocating
1134 #define PUSH_PATTERN_OP(POINTER, FAIL_STACK) \
1135 ((FAIL_STACK_FULL () \
1136 && !DOUBLE_FAIL_STACK (FAIL_STACK)) \
1138 : ((FAIL_STACK).stack[(FAIL_STACK).avail++].pointer = POINTER, \
1141 /* Push a pointer value onto the failure stack.
1142 Assumes the variable `fail_stack'. Probably should only
1143 be called from within `PUSH_FAILURE_POINT'. */
1144 #define PUSH_FAILURE_POINTER(item) \
1145 fail_stack.stack[fail_stack.avail++].pointer = (unsigned char *) (item)
1147 /* This pushes an integer-valued item onto the failure stack.
1148 Assumes the variable `fail_stack'. Probably should only
1149 be called from within `PUSH_FAILURE_POINT'. */
1150 #define PUSH_FAILURE_INT(item) \
1151 fail_stack.stack[fail_stack.avail++].integer = (item)
1153 /* Push a fail_stack_elt_t value onto the failure stack.
1154 Assumes the variable `fail_stack'. Probably should only
1155 be called from within `PUSH_FAILURE_POINT'. */
1156 #define PUSH_FAILURE_ELT(item) \
1157 fail_stack.stack[fail_stack.avail++] = (item)
1159 /* These three POP... operations complement the three PUSH... operations.
1160 All assume that `fail_stack' is nonempty. */
1161 #define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
1162 #define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
1163 #define POP_FAILURE_ELT() fail_stack.stack[--fail_stack.avail]
1165 /* Used to omit pushing failure point id's when we're not debugging. */
1167 # define DEBUG_PUSH PUSH_FAILURE_INT
1168 # define DEBUG_POP(item_addr) *(item_addr) = POP_FAILURE_INT ()
1170 # define DEBUG_PUSH(item)
1171 # define DEBUG_POP(item_addr)
1175 /* Push the information about the state we will need
1176 if we ever fail back to it.
1178 Requires variables fail_stack, regstart, regend, reg_info, and
1179 num_regs_pushed be declared. DOUBLE_FAIL_STACK requires `destination'
1182 Does `return FAILURE_CODE' if runs out of memory. */
1184 #define PUSH_FAILURE_POINT(pattern_place, string_place, failure_code) \
1186 char *destination; \
1187 /* Must be int, so when we don't save any registers, the arithmetic \
1188 of 0 + -1 isn't done as unsigned. */ \
1189 /* Can't be int, since there is not a shred of a guarantee that int \
1190 is wide enough to hold a value of something to which pointer can \
1192 active_reg_t this_reg; \
1194 DEBUG_STATEMENT (failure_id++); \
1195 DEBUG_STATEMENT (nfailure_points_pushed++); \
1196 DEBUG_PRINT2 ("\nPUSH_FAILURE_POINT #%u:\n", failure_id); \
1197 DEBUG_PRINT2 (" Before push, next avail: %d\n", (fail_stack).avail);\
1198 DEBUG_PRINT2 (" size: %d\n", (fail_stack).size);\
1200 DEBUG_PRINT2 (" slots needed: %ld\n", NUM_FAILURE_ITEMS); \
1201 DEBUG_PRINT2 (" available: %d\n", REMAINING_AVAIL_SLOTS); \
1203 /* Ensure we have enough space allocated for what we will push. */ \
1204 while (REMAINING_AVAIL_SLOTS < NUM_FAILURE_ITEMS) \
1206 if (!DOUBLE_FAIL_STACK (fail_stack)) \
1207 return failure_code; \
1209 DEBUG_PRINT2 ("\n Doubled stack; size now: %d\n", \
1210 (fail_stack).size); \
1211 DEBUG_PRINT2 (" slots available: %d\n", REMAINING_AVAIL_SLOTS);\
1214 /* Push the info, starting with the registers. */ \
1215 DEBUG_PRINT1 ("\n"); \
1218 for (this_reg = lowest_active_reg; this_reg <= highest_active_reg; \
1221 DEBUG_PRINT2 (" Pushing reg: %lu\n", this_reg); \
1222 DEBUG_STATEMENT (num_regs_pushed++); \
1224 DEBUG_PRINT2 (" start: %p\n", regstart[this_reg]); \
1225 PUSH_FAILURE_POINTER (regstart[this_reg]); \
1227 DEBUG_PRINT2 (" end: %p\n", regend[this_reg]); \
1228 PUSH_FAILURE_POINTER (regend[this_reg]); \
1230 DEBUG_PRINT2 (" info: %p\n ", \
1231 reg_info[this_reg].word.pointer); \
1232 DEBUG_PRINT2 (" match_null=%d", \
1233 REG_MATCH_NULL_STRING_P (reg_info[this_reg])); \
1234 DEBUG_PRINT2 (" active=%d", IS_ACTIVE (reg_info[this_reg])); \
1235 DEBUG_PRINT2 (" matched_something=%d", \
1236 MATCHED_SOMETHING (reg_info[this_reg])); \
1237 DEBUG_PRINT2 (" ever_matched=%d", \
1238 EVER_MATCHED_SOMETHING (reg_info[this_reg])); \
1239 DEBUG_PRINT1 ("\n"); \
1240 PUSH_FAILURE_ELT (reg_info[this_reg].word); \
1243 DEBUG_PRINT2 (" Pushing low active reg: %ld\n", lowest_active_reg);\
1244 PUSH_FAILURE_INT (lowest_active_reg); \
1246 DEBUG_PRINT2 (" Pushing high active reg: %ld\n", highest_active_reg);\
1247 PUSH_FAILURE_INT (highest_active_reg); \
1249 DEBUG_PRINT2 (" Pushing pattern %p:\n", pattern_place); \
1250 DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern_place, pend); \
1251 PUSH_FAILURE_POINTER (pattern_place); \
1253 DEBUG_PRINT2 (" Pushing string %p: `", string_place); \
1254 DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2, \
1256 DEBUG_PRINT1 ("'\n"); \
1257 PUSH_FAILURE_POINTER (string_place); \
1259 DEBUG_PRINT2 (" Pushing failure id: %u\n", failure_id); \
1260 DEBUG_PUSH (failure_id); \
1263 /* This is the number of items that are pushed and popped on the stack
1264 for each register. */
1265 #define NUM_REG_ITEMS 3
1267 /* Individual items aside from the registers. */
1269 # define NUM_NONREG_ITEMS 5 /* Includes failure point id. */
1271 # define NUM_NONREG_ITEMS 4
1274 /* We push at most this many items on the stack. */
1275 /* We used to use (num_regs - 1), which is the number of registers
1276 this regexp will save; but that was changed to 5
1277 to avoid stack overflow for a regexp with lots of parens. */
1278 #define MAX_FAILURE_ITEMS (5 * NUM_REG_ITEMS + NUM_NONREG_ITEMS)
1280 /* We actually push this many items. */
1281 #define NUM_FAILURE_ITEMS \
1283 ? 0 : highest_active_reg - lowest_active_reg + 1) \
1287 /* How many items can still be added to the stack without overflowing it. */
1288 #define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
1291 /* Pops what PUSH_FAIL_STACK pushes.
1293 We restore into the parameters, all of which should be lvalues:
1294 STR -- the saved data position.
1295 PAT -- the saved pattern position.
1296 LOW_REG, HIGH_REG -- the highest and lowest active registers.
1297 REGSTART, REGEND -- arrays of string positions.
1298 REG_INFO -- array of information about each subexpression.
1300 Also assumes the variables `fail_stack' and (if debugging), `bufp',
1301 `pend', `string1', `size1', `string2', and `size2'. */
1303 #define POP_FAILURE_POINT(str, pat, low_reg, high_reg, regstart, regend, reg_info)\
1305 DEBUG_STATEMENT (unsigned failure_id;) \
1306 active_reg_t this_reg; \
1307 const unsigned char *string_temp; \
1309 assert (!FAIL_STACK_EMPTY ()); \
1311 /* Remove failure points and point to how many regs pushed. */ \
1312 DEBUG_PRINT1 ("POP_FAILURE_POINT:\n"); \
1313 DEBUG_PRINT2 (" Before pop, next avail: %d\n", fail_stack.avail); \
1314 DEBUG_PRINT2 (" size: %d\n", fail_stack.size); \
1316 assert (fail_stack.avail >= NUM_NONREG_ITEMS); \
1318 DEBUG_POP (&failure_id); \
1319 DEBUG_PRINT2 (" Popping failure id: %u\n", failure_id); \
1321 /* If the saved string location is NULL, it came from an \
1322 on_failure_keep_string_jump opcode, and we want to throw away the \
1323 saved NULL, thus retaining our current position in the string. */ \
1324 string_temp = POP_FAILURE_POINTER (); \
1325 if (string_temp != NULL) \
1326 str = (const char *) string_temp; \
1328 DEBUG_PRINT2 (" Popping string %p: `", str); \
1329 DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2); \
1330 DEBUG_PRINT1 ("'\n"); \
1332 pat = (unsigned char *) POP_FAILURE_POINTER (); \
1333 DEBUG_PRINT2 (" Popping pattern %p:\n", pat); \
1334 DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend); \
1336 /* Restore register info. */ \
1337 high_reg = (active_reg_t) POP_FAILURE_INT (); \
1338 DEBUG_PRINT2 (" Popping high active reg: %ld\n", high_reg); \
1340 low_reg = (active_reg_t) POP_FAILURE_INT (); \
1341 DEBUG_PRINT2 (" Popping low active reg: %ld\n", low_reg); \
1344 for (this_reg = high_reg; this_reg >= low_reg; this_reg--) \
1346 DEBUG_PRINT2 (" Popping reg: %ld\n", this_reg); \
1348 reg_info[this_reg].word = POP_FAILURE_ELT (); \
1349 DEBUG_PRINT2 (" info: %p\n", \
1350 reg_info[this_reg].word.pointer); \
1352 regend[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1353 DEBUG_PRINT2 (" end: %p\n", regend[this_reg]); \
1355 regstart[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1356 DEBUG_PRINT2 (" start: %p\n", regstart[this_reg]); \
1360 for (this_reg = highest_active_reg; this_reg > high_reg; this_reg--) \
1362 reg_info[this_reg].word.integer = 0; \
1363 regend[this_reg] = 0; \
1364 regstart[this_reg] = 0; \
1366 highest_active_reg = high_reg; \
1369 set_regs_matched_done = 0; \
1370 DEBUG_STATEMENT (nfailure_points_popped++); \
1371 } /* POP_FAILURE_POINT */
1375 /* Structure for per-register (a.k.a. per-group) information.
1376 Other register information, such as the
1377 starting and ending positions (which are addresses), and the list of
1378 inner groups (which is a bits list) are maintained in separate
1381 We are making a (strictly speaking) nonportable assumption here: that
1382 the compiler will pack our bit fields into something that fits into
1383 the type of `word', i.e., is something that fits into one item on the
1387 /* Declarations and macros for re_match_2. */
1391 fail_stack_elt_t word;
1394 /* This field is one if this group can match the empty string,
1395 zero if not. If not yet determined, `MATCH_NULL_UNSET_VALUE'. */
1396 #define MATCH_NULL_UNSET_VALUE 3
1397 unsigned match_null_string_p : 2;
1398 unsigned is_active : 1;
1399 unsigned matched_something : 1;
1400 unsigned ever_matched_something : 1;
1402 } register_info_type;
1404 #define REG_MATCH_NULL_STRING_P(R) ((R).bits.match_null_string_p)
1405 #define IS_ACTIVE(R) ((R).bits.is_active)
1406 #define MATCHED_SOMETHING(R) ((R).bits.matched_something)
1407 #define EVER_MATCHED_SOMETHING(R) ((R).bits.ever_matched_something)
1410 /* Call this when have matched a real character; it sets `matched' flags
1411 for the subexpressions which we are currently inside. Also records
1412 that those subexprs have matched. */
1413 #define SET_REGS_MATCHED() \
1416 if (!set_regs_matched_done) \
1419 set_regs_matched_done = 1; \
1420 for (r = lowest_active_reg; r <= highest_active_reg; r++) \
1422 MATCHED_SOMETHING (reg_info[r]) \
1423 = EVER_MATCHED_SOMETHING (reg_info[r]) \
1430 /* Registers are set to a sentinel when they haven't yet matched. */
1431 static char reg_unset_dummy;
1432 #define REG_UNSET_VALUE (®_unset_dummy)
1433 #define REG_UNSET(e) ((e) == REG_UNSET_VALUE)
1435 /* Subroutine declarations and macros for regex_compile. */
1437 static reg_errcode_t regex_compile _RE_ARGS ((const char *pattern, size_t size,
1438 reg_syntax_t syntax,
1439 struct re_pattern_buffer *bufp));
1440 static void store_op1 _RE_ARGS ((re_opcode_t op, unsigned char *loc, int arg));
1441 static void store_op2 _RE_ARGS ((re_opcode_t op, unsigned char *loc,
1442 int arg1, int arg2));
1443 static void insert_op1 _RE_ARGS ((re_opcode_t op, unsigned char *loc,
1444 int arg, unsigned char *end));
1445 static void insert_op2 _RE_ARGS ((re_opcode_t op, unsigned char *loc,
1446 int arg1, int arg2, unsigned char *end));
1447 static boolean at_begline_loc_p _RE_ARGS ((const char *pattern, const char *p,
1448 reg_syntax_t syntax));
1449 static boolean at_endline_loc_p _RE_ARGS ((const char *p, const char *pend,
1450 reg_syntax_t syntax));
1451 static reg_errcode_t compile_range _RE_ARGS ((const char **p_ptr,
1454 reg_syntax_t syntax,
1457 /* Fetch the next character in the uncompiled pattern---translating it
1458 if necessary. Also cast from a signed character in the constant
1459 string passed to us by the user to an unsigned char that we can use
1460 as an array index (in, e.g., `translate'). */
1462 # define PATFETCH(c) \
1463 do {if (p == pend) return REG_EEND; \
1464 c = (unsigned char) *p++; \
1465 if (translate) c = (unsigned char) translate[c]; \
1469 /* Fetch the next character in the uncompiled pattern, with no
1471 #define PATFETCH_RAW(c) \
1472 do {if (p == pend) return REG_EEND; \
1473 c = (unsigned char) *p++; \
1476 /* Go backwards one character in the pattern. */
1477 #define PATUNFETCH p--
1480 /* If `translate' is non-null, return translate[D], else just D. We
1481 cast the subscript to translate because some data is declared as
1482 `char *', to avoid warnings when a string constant is passed. But
1483 when we use a character as a subscript we must make it unsigned. */
1485 # define TRANSLATE(d) \
1486 (translate ? (char) translate[(unsigned char) (d)] : (d))
1490 /* Macros for outputting the compiled pattern into `buffer'. */
1492 /* If the buffer isn't allocated when it comes in, use this. */
1493 #define INIT_BUF_SIZE 32
1495 /* Make sure we have at least N more bytes of space in buffer. */
1496 #define GET_BUFFER_SPACE(n) \
1497 while ((unsigned long) (b - bufp->buffer + (n)) > bufp->allocated) \
1500 /* Make sure we have one more byte of buffer space and then add C to it. */
1501 #define BUF_PUSH(c) \
1503 GET_BUFFER_SPACE (1); \
1504 *b++ = (unsigned char) (c); \
1508 /* Ensure we have two more bytes of buffer space and then append C1 and C2. */
1509 #define BUF_PUSH_2(c1, c2) \
1511 GET_BUFFER_SPACE (2); \
1512 *b++ = (unsigned char) (c1); \
1513 *b++ = (unsigned char) (c2); \
1517 /* As with BUF_PUSH_2, except for three bytes. */
1518 #define BUF_PUSH_3(c1, c2, c3) \
1520 GET_BUFFER_SPACE (3); \
1521 *b++ = (unsigned char) (c1); \
1522 *b++ = (unsigned char) (c2); \
1523 *b++ = (unsigned char) (c3); \
1527 /* Store a jump with opcode OP at LOC to location TO. We store a
1528 relative address offset by the three bytes the jump itself occupies. */
1529 #define STORE_JUMP(op, loc, to) \
1530 store_op1 (op, loc, (int) ((to) - (loc) - 3))
1532 /* Likewise, for a two-argument jump. */
1533 #define STORE_JUMP2(op, loc, to, arg) \
1534 store_op2 (op, loc, (int) ((to) - (loc) - 3), arg)
1536 /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
1537 #define INSERT_JUMP(op, loc, to) \
1538 insert_op1 (op, loc, (int) ((to) - (loc) - 3), b)
1540 /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
1541 #define INSERT_JUMP2(op, loc, to, arg) \
1542 insert_op2 (op, loc, (int) ((to) - (loc) - 3), arg, b)
1545 /* This is not an arbitrary limit: the arguments which represent offsets
1546 into the pattern are two bytes long. So if 2^16 bytes turns out to
1547 be too small, many things would have to change. */
1548 /* Any other compiler which, like MSC, has allocation limit below 2^16
1549 bytes will have to use approach similar to what was done below for
1550 MSC and drop MAX_BUF_SIZE a bit. Otherwise you may end up
1551 reallocating to 0 bytes. Such thing is not going to work too well.
1552 You have been warned!! */
1553 #if defined _MSC_VER && !defined WIN32
1554 /* Microsoft C 16-bit versions limit malloc to approx 65512 bytes.
1555 The REALLOC define eliminates a flurry of conversion warnings,
1556 but is not required. */
1557 # define MAX_BUF_SIZE 65500L
1558 # define REALLOC(p,s) realloc ((p), (size_t) (s))
1560 # define MAX_BUF_SIZE (1L << 16)
1561 # define REALLOC(p,s) realloc ((p), (s))
1564 /* Extend the buffer by twice its current size via realloc and
1565 reset the pointers that pointed into the old block to point to the
1566 correct places in the new one. If extending the buffer results in it
1567 being larger than MAX_BUF_SIZE, then flag memory exhausted. */
1568 #define EXTEND_BUFFER() \
1570 unsigned char *old_buffer = bufp->buffer; \
1571 if (bufp->allocated == MAX_BUF_SIZE) \
1573 bufp->allocated <<= 1; \
1574 if (bufp->allocated > MAX_BUF_SIZE) \
1575 bufp->allocated = MAX_BUF_SIZE; \
1576 bufp->buffer = (unsigned char *) REALLOC (bufp->buffer, bufp->allocated);\
1577 if (bufp->buffer == NULL) \
1578 return REG_ESPACE; \
1579 /* If the buffer moved, move all the pointers into it. */ \
1580 if (old_buffer != bufp->buffer) \
1582 b = (b - old_buffer) + bufp->buffer; \
1583 begalt = (begalt - old_buffer) + bufp->buffer; \
1584 if (fixup_alt_jump) \
1585 fixup_alt_jump = (fixup_alt_jump - old_buffer) + bufp->buffer;\
1587 laststart = (laststart - old_buffer) + bufp->buffer; \
1588 if (pending_exact) \
1589 pending_exact = (pending_exact - old_buffer) + bufp->buffer; \
1594 /* Since we have one byte reserved for the register number argument to
1595 {start,stop}_memory, the maximum number of groups we can report
1596 things about is what fits in that byte. */
1597 #define MAX_REGNUM 255
1599 /* But patterns can have more than `MAX_REGNUM' registers. We just
1600 ignore the excess. */
1601 typedef unsigned regnum_t;
1604 /* Macros for the compile stack. */
1606 /* Since offsets can go either forwards or backwards, this type needs to
1607 be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
1608 /* int may be not enough when sizeof(int) == 2. */
1609 typedef long pattern_offset_t;
1613 pattern_offset_t begalt_offset;
1614 pattern_offset_t fixup_alt_jump;
1615 pattern_offset_t inner_group_offset;
1616 pattern_offset_t laststart_offset;
1618 } compile_stack_elt_t;
1623 compile_stack_elt_t *stack;
1625 unsigned avail; /* Offset of next open position. */
1626 } compile_stack_type;
1629 #define INIT_COMPILE_STACK_SIZE 32
1631 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
1632 #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
1634 /* The next available element. */
1635 #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
1638 /* Set the bit for character C in a list. */
1639 #define SET_LIST_BIT(c) \
1640 (b[((unsigned char) (c)) / BYTEWIDTH] \
1641 |= 1 << (((unsigned char) c) % BYTEWIDTH))
1644 /* Get the next unsigned number in the uncompiled pattern. */
1645 #define GET_UNSIGNED_NUMBER(num) \
1649 while (ISDIGIT (c)) \
1653 num = num * 10 + c - '0'; \
1661 #if defined _LIBC || (defined HAVE_WCTYPE_H && defined HAVE_WCHAR_H)
1662 /* The GNU C library provides support for user-defined character classes
1663 and the functions from ISO C amendement 1. */
1664 # ifdef CHARCLASS_NAME_MAX
1665 # define CHAR_CLASS_MAX_LENGTH CHARCLASS_NAME_MAX
1667 /* This shouldn't happen but some implementation might still have this
1668 problem. Use a reasonable default value. */
1669 # define CHAR_CLASS_MAX_LENGTH 256
1673 # define IS_CHAR_CLASS(string) __wctype (string)
1675 # define IS_CHAR_CLASS(string) wctype (string)
1678 # define CHAR_CLASS_MAX_LENGTH 6 /* Namely, `xdigit'. */
1680 # define IS_CHAR_CLASS(string) \
1681 (STREQ (string, "alpha") || STREQ (string, "upper") \
1682 || STREQ (string, "lower") || STREQ (string, "digit") \
1683 || STREQ (string, "alnum") || STREQ (string, "xdigit") \
1684 || STREQ (string, "space") || STREQ (string, "print") \
1685 || STREQ (string, "punct") || STREQ (string, "graph") \
1686 || STREQ (string, "cntrl") || STREQ (string, "blank"))
1689 #ifndef MATCH_MAY_ALLOCATE
1691 /* If we cannot allocate large objects within re_match_2_internal,
1692 we make the fail stack and register vectors global.
1693 The fail stack, we grow to the maximum size when a regexp
1695 The register vectors, we adjust in size each time we
1696 compile a regexp, according to the number of registers it needs. */
1698 static fail_stack_type fail_stack;
1700 /* Size with which the following vectors are currently allocated.
1701 That is so we can make them bigger as needed,
1702 but never make them smaller. */
1703 static int regs_allocated_size;
1705 static const char ** regstart, ** regend;
1706 static const char ** old_regstart, ** old_regend;
1707 static const char **best_regstart, **best_regend;
1708 static register_info_type *reg_info;
1709 static const char **reg_dummy;
1710 static register_info_type *reg_info_dummy;
1712 /* Make the register vectors big enough for NUM_REGS registers,
1713 but don't make them smaller. */
1716 regex_grow_registers (num_regs)
1719 if (num_regs > regs_allocated_size)
1721 RETALLOC_IF (regstart, num_regs, const char *);
1722 RETALLOC_IF (regend, num_regs, const char *);
1723 RETALLOC_IF (old_regstart, num_regs, const char *);
1724 RETALLOC_IF (old_regend, num_regs, const char *);
1725 RETALLOC_IF (best_regstart, num_regs, const char *);
1726 RETALLOC_IF (best_regend, num_regs, const char *);
1727 RETALLOC_IF (reg_info, num_regs, register_info_type);
1728 RETALLOC_IF (reg_dummy, num_regs, const char *);
1729 RETALLOC_IF (reg_info_dummy, num_regs, register_info_type);
1731 regs_allocated_size = num_regs;
1735 #endif /* not MATCH_MAY_ALLOCATE */
1737 static boolean group_in_compile_stack _RE_ARGS ((compile_stack_type
1741 /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
1742 Returns one of error codes defined in `gnu-regex.h', or zero for success.
1744 Assumes the `allocated' (and perhaps `buffer') and `translate'
1745 fields are set in BUFP on entry.
1747 If it succeeds, results are put in BUFP (if it returns an error, the
1748 contents of BUFP are undefined):
1749 `buffer' is the compiled pattern;
1750 `syntax' is set to SYNTAX;
1751 `used' is set to the length of the compiled pattern;
1752 `fastmap_accurate' is zero;
1753 `re_nsub' is the number of subexpressions in PATTERN;
1754 `not_bol' and `not_eol' are zero;
1756 The `fastmap' and `newline_anchor' fields are neither
1757 examined nor set. */
1759 /* Return, freeing storage we allocated. */
1760 #define FREE_STACK_RETURN(value) \
1761 return (free (compile_stack.stack), value)
1763 static reg_errcode_t
1764 regex_compile (pattern, size, syntax, bufp)
1765 const char *pattern;
1767 reg_syntax_t syntax;
1768 struct re_pattern_buffer *bufp;
1770 /* We fetch characters from PATTERN here. Even though PATTERN is
1771 `char *' (i.e., signed), we declare these variables as unsigned, so
1772 they can be reliably used as array indices. */
1773 register unsigned char c, c1;
1775 /* A random temporary spot in PATTERN. */
1778 /* Points to the end of the buffer, where we should append. */
1779 register unsigned char *b;
1781 /* Keeps track of unclosed groups. */
1782 compile_stack_type compile_stack;
1784 /* Points to the current (ending) position in the pattern. */
1785 const char *p = pattern;
1786 const char *pend = pattern + size;
1788 /* How to translate the characters in the pattern. */
1789 RE_TRANSLATE_TYPE translate = bufp->translate;
1791 /* Address of the count-byte of the most recently inserted `exactn'
1792 command. This makes it possible to tell if a new exact-match
1793 character can be added to that command or if the character requires
1794 a new `exactn' command. */
1795 unsigned char *pending_exact = 0;
1797 /* Address of start of the most recently finished expression.
1798 This tells, e.g., postfix * where to find the start of its
1799 operand. Reset at the beginning of groups and alternatives. */
1800 unsigned char *laststart = 0;
1802 /* Address of beginning of regexp, or inside of last group. */
1803 unsigned char *begalt;
1805 /* Place in the uncompiled pattern (i.e., the {) to
1806 which to go back if the interval is invalid. */
1807 const char *beg_interval;
1809 /* Address of the place where a forward jump should go to the end of
1810 the containing expression. Each alternative of an `or' -- except the
1811 last -- ends with a forward jump of this sort. */
1812 unsigned char *fixup_alt_jump = 0;
1814 /* Counts open-groups as they are encountered. Remembered for the
1815 matching close-group on the compile stack, so the same register
1816 number is put in the stop_memory as the start_memory. */
1817 regnum_t regnum = 0;
1820 DEBUG_PRINT1 ("\nCompiling pattern: ");
1823 unsigned debug_count;
1825 for (debug_count = 0; debug_count < size; debug_count++)
1826 putchar (pattern[debug_count]);
1831 /* Initialize the compile stack. */
1832 compile_stack.stack = TALLOC (INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
1833 if (compile_stack.stack == NULL)
1836 compile_stack.size = INIT_COMPILE_STACK_SIZE;
1837 compile_stack.avail = 0;
1839 /* Initialize the pattern buffer. */
1840 bufp->syntax = syntax;
1841 bufp->fastmap_accurate = 0;
1842 bufp->not_bol = bufp->not_eol = 0;
1844 /* Set `used' to zero, so that if we return an error, the pattern
1845 printer (for debugging) will think there's no pattern. We reset it
1849 /* Always count groups, whether or not bufp->no_sub is set. */
1852 #if !defined emacs && !defined SYNTAX_TABLE
1853 /* Initialize the syntax table. */
1854 init_syntax_once ();
1857 if (bufp->allocated == 0)
1860 { /* If zero allocated, but buffer is non-null, try to realloc
1861 enough space. This loses if buffer's address is bogus, but
1862 that is the user's responsibility. */
1863 RETALLOC (bufp->buffer, INIT_BUF_SIZE, unsigned char);
1866 { /* Caller did not allocate a buffer. Do it for them. */
1867 bufp->buffer = TALLOC (INIT_BUF_SIZE, unsigned char);
1869 if (!bufp->buffer) FREE_STACK_RETURN (REG_ESPACE);
1871 bufp->allocated = INIT_BUF_SIZE;
1874 begalt = b = bufp->buffer;
1876 /* Loop through the uncompiled pattern until we're at the end. */
1885 if ( /* If at start of pattern, it's an operator. */
1887 /* If context independent, it's an operator. */
1888 || syntax & RE_CONTEXT_INDEP_ANCHORS
1889 /* Otherwise, depends on what's come before. */
1890 || at_begline_loc_p (pattern, p, syntax))
1900 if ( /* If at end of pattern, it's an operator. */
1902 /* If context independent, it's an operator. */
1903 || syntax & RE_CONTEXT_INDEP_ANCHORS
1904 /* Otherwise, depends on what's next. */
1905 || at_endline_loc_p (p, pend, syntax))
1915 if ((syntax & RE_BK_PLUS_QM)
1916 || (syntax & RE_LIMITED_OPS))
1920 /* If there is no previous pattern... */
1923 if (syntax & RE_CONTEXT_INVALID_OPS)
1924 FREE_STACK_RETURN (REG_BADRPT);
1925 else if (!(syntax & RE_CONTEXT_INDEP_OPS))
1930 /* Are we optimizing this jump? */
1931 boolean keep_string_p = false;
1933 /* 1 means zero (many) matches is allowed. */
1934 char zero_times_ok = 0, many_times_ok = 0;
1936 /* If there is a sequence of repetition chars, collapse it
1937 down to just one (the right one). We can't combine
1938 interval operators with these because of, e.g., `a{2}*',
1939 which should only match an even number of `a's. */
1943 zero_times_ok |= c != '+';
1944 many_times_ok |= c != '?';
1952 || (!(syntax & RE_BK_PLUS_QM) && (c == '+' || c == '?')))
1955 else if (syntax & RE_BK_PLUS_QM && c == '\\')
1957 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
1960 if (!(c1 == '+' || c1 == '?'))
1975 /* If we get here, we found another repeat character. */
1978 /* Star, etc. applied to an empty pattern is equivalent
1979 to an empty pattern. */
1983 /* Now we know whether or not zero matches is allowed
1984 and also whether or not two or more matches is allowed. */
1986 { /* More than one repetition is allowed, so put in at the
1987 end a backward relative jump from `b' to before the next
1988 jump we're going to put in below (which jumps from
1989 laststart to after this jump).
1991 But if we are at the `*' in the exact sequence `.*\n',
1992 insert an unconditional jump backwards to the .,
1993 instead of the beginning of the loop. This way we only
1994 push a failure point once, instead of every time
1995 through the loop. */
1996 assert (p - 1 > pattern);
1998 /* Allocate the space for the jump. */
1999 GET_BUFFER_SPACE (3);
2001 /* We know we are not at the first character of the pattern,
2002 because laststart was nonzero. And we've already
2003 incremented `p', by the way, to be the character after
2004 the `*'. Do we have to do something analogous here
2005 for null bytes, because of RE_DOT_NOT_NULL? */
2006 if (TRANSLATE (*(p - 2)) == TRANSLATE ('.')
2008 && p < pend && TRANSLATE (*p) == TRANSLATE ('\n')
2009 && !(syntax & RE_DOT_NEWLINE))
2010 { /* We have .*\n. */
2011 STORE_JUMP (jump, b, laststart);
2012 keep_string_p = true;
2015 /* Anything else. */
2016 STORE_JUMP (maybe_pop_jump, b, laststart - 3);
2018 /* We've added more stuff to the buffer. */
2022 /* On failure, jump from laststart to b + 3, which will be the
2023 end of the buffer after this jump is inserted. */
2024 GET_BUFFER_SPACE (3);
2025 INSERT_JUMP (keep_string_p ? on_failure_keep_string_jump
2033 /* At least one repetition is required, so insert a
2034 `dummy_failure_jump' before the initial
2035 `on_failure_jump' instruction of the loop. This
2036 effects a skip over that instruction the first time
2037 we hit that loop. */
2038 GET_BUFFER_SPACE (3);
2039 INSERT_JUMP (dummy_failure_jump, laststart, laststart + 6);
2054 boolean had_char_class = false;
2056 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2058 /* Ensure that we have enough space to push a charset: the
2059 opcode, the length count, and the bitset; 34 bytes in all. */
2060 GET_BUFFER_SPACE (34);
2064 /* We test `*p == '^' twice, instead of using an if
2065 statement, so we only need one BUF_PUSH. */
2066 BUF_PUSH (*p == '^' ? charset_not : charset);
2070 /* Remember the first position in the bracket expression. */
2073 /* Push the number of bytes in the bitmap. */
2074 BUF_PUSH ((1 << BYTEWIDTH) / BYTEWIDTH);
2076 /* Clear the whole map. */
2077 bzero (b, (1 << BYTEWIDTH) / BYTEWIDTH);
2079 /* charset_not matches newline according to a syntax bit. */
2080 if ((re_opcode_t) b[-2] == charset_not
2081 && (syntax & RE_HAT_LISTS_NOT_NEWLINE))
2082 SET_LIST_BIT ('\n');
2084 /* Read in characters and ranges, setting map bits. */
2087 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2091 /* \ might escape characters inside [...] and [^...]. */
2092 if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\')
2094 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2101 /* Could be the end of the bracket expression. If it's
2102 not (i.e., when the bracket expression is `[]' so
2103 far), the ']' character bit gets set way below. */
2104 if (c == ']' && p != p1 + 1)
2107 /* Look ahead to see if it's a range when the last thing
2108 was a character class. */
2109 if (had_char_class && c == '-' && *p != ']')
2110 FREE_STACK_RETURN (REG_ERANGE);
2112 /* Look ahead to see if it's a range when the last thing
2113 was a character: if this is a hyphen not at the
2114 beginning or the end of a list, then it's the range
2117 && !(p - 2 >= pattern && p[-2] == '[')
2118 && !(p - 3 >= pattern && p[-3] == '[' && p[-2] == '^')
2122 = compile_range (&p, pend, translate, syntax, b);
2123 if (ret != REG_NOERROR) FREE_STACK_RETURN (ret);
2126 else if (p[0] == '-' && p[1] != ']')
2127 { /* This handles ranges made up of characters only. */
2130 /* Move past the `-'. */
2133 ret = compile_range (&p, pend, translate, syntax, b);
2134 if (ret != REG_NOERROR) FREE_STACK_RETURN (ret);
2137 /* See if we're at the beginning of a possible character
2140 else if (syntax & RE_CHAR_CLASSES && c == '[' && *p == ':')
2141 { /* Leave room for the null. */
2142 char str[CHAR_CLASS_MAX_LENGTH + 1];
2147 /* If pattern is `[[:'. */
2148 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2153 if ((c == ':' && *p == ']') || p == pend
2154 || c1 == CHAR_CLASS_MAX_LENGTH)
2160 /* If isn't a word bracketed by `[:' and `:]':
2161 undo the ending character, the letters, and leave
2162 the leading `:' and `[' (but set bits for them). */
2163 if (c == ':' && *p == ']')
2165 /* GCC LOCAL: Skip this code if we don't have btowc(). btowc() is */
2166 /* defined in the 1994 Amendment 1 to ISO C and may not be present on */
2167 /* systems where we have wchar.h and wctype.h. */
2168 #if defined _LIBC || (defined HAVE_WCTYPE_H && defined HAVE_WCHAR_H && defined HAVE_BTOWC)
2169 boolean is_lower = STREQ (str, "lower");
2170 boolean is_upper = STREQ (str, "upper");
2174 wt = IS_CHAR_CLASS (str);
2176 FREE_STACK_RETURN (REG_ECTYPE);
2178 /* Throw away the ] at the end of the character
2182 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2184 for (ch = 0; ch < 1 << BYTEWIDTH; ++ch)
2187 if (__iswctype (__btowc (ch), wt))
2190 if (iswctype (btowc (ch), wt))
2194 if (translate && (is_upper || is_lower)
2195 && (ISUPPER (ch) || ISLOWER (ch)))
2199 had_char_class = true;
2202 boolean is_alnum = STREQ (str, "alnum");
2203 boolean is_alpha = STREQ (str, "alpha");
2204 boolean is_blank = STREQ (str, "blank");
2205 boolean is_cntrl = STREQ (str, "cntrl");
2206 boolean is_digit = STREQ (str, "digit");
2207 boolean is_graph = STREQ (str, "graph");
2208 boolean is_lower = STREQ (str, "lower");
2209 boolean is_print = STREQ (str, "print");
2210 boolean is_punct = STREQ (str, "punct");
2211 boolean is_space = STREQ (str, "space");
2212 boolean is_upper = STREQ (str, "upper");
2213 boolean is_xdigit = STREQ (str, "xdigit");
2215 if (!IS_CHAR_CLASS (str))
2216 FREE_STACK_RETURN (REG_ECTYPE);
2218 /* Throw away the ] at the end of the character
2222 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2224 for (ch = 0; ch < 1 << BYTEWIDTH; ch++)
2226 /* This was split into 3 if's to
2227 avoid an arbitrary limit in some compiler. */
2228 if ( (is_alnum && ISALNUM (ch))
2229 || (is_alpha && ISALPHA (ch))
2230 || (is_blank && ISBLANK (ch))
2231 || (is_cntrl && ISCNTRL (ch)))
2233 if ( (is_digit && ISDIGIT (ch))
2234 || (is_graph && ISGRAPH (ch))
2235 || (is_lower && ISLOWER (ch))
2236 || (is_print && ISPRINT (ch)))
2238 if ( (is_punct && ISPUNCT (ch))
2239 || (is_space && ISSPACE (ch))
2240 || (is_upper && ISUPPER (ch))
2241 || (is_xdigit && ISXDIGIT (ch)))
2243 if ( translate && (is_upper || is_lower)
2244 && (ISUPPER (ch) || ISLOWER (ch)))
2247 had_char_class = true;
2248 #endif /* libc || wctype.h */
2257 had_char_class = false;
2262 had_char_class = false;
2267 /* Discard any (non)matching list bytes that are all 0 at the
2268 end of the map. Decrease the map-length byte too. */
2269 while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
2277 if (syntax & RE_NO_BK_PARENS)
2284 if (syntax & RE_NO_BK_PARENS)
2291 if (syntax & RE_NEWLINE_ALT)
2298 if (syntax & RE_NO_BK_VBAR)
2305 if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
2306 goto handle_interval;
2312 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2314 /* Do not translate the character after the \, so that we can
2315 distinguish, e.g., \B from \b, even if we normally would
2316 translate, e.g., B to b. */
2322 if (syntax & RE_NO_BK_PARENS)
2323 goto normal_backslash;
2329 if (COMPILE_STACK_FULL)
2331 RETALLOC (compile_stack.stack, compile_stack.size << 1,
2332 compile_stack_elt_t);
2333 if (compile_stack.stack == NULL) return REG_ESPACE;
2335 compile_stack.size <<= 1;
2338 /* These are the values to restore when we hit end of this
2339 group. They are all relative offsets, so that if the
2340 whole pattern moves because of realloc, they will still
2342 COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
2343 COMPILE_STACK_TOP.fixup_alt_jump
2344 = fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
2345 COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
2346 COMPILE_STACK_TOP.regnum = regnum;
2348 /* We will eventually replace the 0 with the number of
2349 groups inner to this one. But do not push a
2350 start_memory for groups beyond the last one we can
2351 represent in the compiled pattern. */
2352 if (regnum <= MAX_REGNUM)
2354 COMPILE_STACK_TOP.inner_group_offset = b - bufp->buffer + 2;
2355 BUF_PUSH_3 (start_memory, regnum, 0);
2358 compile_stack.avail++;
2363 /* If we've reached MAX_REGNUM groups, then this open
2364 won't actually generate any code, so we'll have to
2365 clear pending_exact explicitly. */
2371 if (syntax & RE_NO_BK_PARENS) goto normal_backslash;
2373 if (COMPILE_STACK_EMPTY)
2375 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
2376 goto normal_backslash;
2378 FREE_STACK_RETURN (REG_ERPAREN);
2383 { /* Push a dummy failure point at the end of the
2384 alternative for a possible future
2385 `pop_failure_jump' to pop. See comments at
2386 `push_dummy_failure' in `re_match_2'. */
2387 BUF_PUSH (push_dummy_failure);
2389 /* We allocated space for this jump when we assigned
2390 to `fixup_alt_jump', in the `handle_alt' case below. */
2391 STORE_JUMP (jump_past_alt, fixup_alt_jump, b - 1);
2394 /* See similar code for backslashed left paren above. */
2395 if (COMPILE_STACK_EMPTY)
2397 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
2400 FREE_STACK_RETURN (REG_ERPAREN);
2403 /* Since we just checked for an empty stack above, this
2404 ``can't happen''. */
2405 assert (compile_stack.avail != 0);
2407 /* We don't just want to restore into `regnum', because
2408 later groups should continue to be numbered higher,
2409 as in `(ab)c(de)' -- the second group is #2. */
2410 regnum_t this_group_regnum;
2412 compile_stack.avail--;
2413 begalt = bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
2415 = COMPILE_STACK_TOP.fixup_alt_jump
2416 ? bufp->buffer + COMPILE_STACK_TOP.fixup_alt_jump - 1
2418 laststart = bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
2419 this_group_regnum = COMPILE_STACK_TOP.regnum;
2420 /* If we've reached MAX_REGNUM groups, then this open
2421 won't actually generate any code, so we'll have to
2422 clear pending_exact explicitly. */
2425 /* We're at the end of the group, so now we know how many
2426 groups were inside this one. */
2427 if (this_group_regnum <= MAX_REGNUM)
2429 unsigned char *inner_group_loc
2430 = bufp->buffer + COMPILE_STACK_TOP.inner_group_offset;
2432 *inner_group_loc = regnum - this_group_regnum;
2433 BUF_PUSH_3 (stop_memory, this_group_regnum,
2434 regnum - this_group_regnum);
2440 case '|': /* `\|'. */
2441 if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
2442 goto normal_backslash;
2444 if (syntax & RE_LIMITED_OPS)
2447 /* Insert before the previous alternative a jump which
2448 jumps to this alternative if the former fails. */
2449 GET_BUFFER_SPACE (3);
2450 INSERT_JUMP (on_failure_jump, begalt, b + 6);
2454 /* The alternative before this one has a jump after it
2455 which gets executed if it gets matched. Adjust that
2456 jump so it will jump to this alternative's analogous
2457 jump (put in below, which in turn will jump to the next
2458 (if any) alternative's such jump, etc.). The last such
2459 jump jumps to the correct final destination. A picture:
2465 If we are at `b', then fixup_alt_jump right now points to a
2466 three-byte space after `a'. We'll put in the jump, set
2467 fixup_alt_jump to right after `b', and leave behind three
2468 bytes which we'll fill in when we get to after `c'. */
2471 STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
2473 /* Mark and leave space for a jump after this alternative,
2474 to be filled in later either by next alternative or
2475 when know we're at the end of a series of alternatives. */
2477 GET_BUFFER_SPACE (3);
2486 /* If \{ is a literal. */
2487 if (!(syntax & RE_INTERVALS)
2488 /* If we're at `\{' and it's not the open-interval
2490 || ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
2491 || (p - 2 == pattern && p == pend))
2492 goto normal_backslash;
2496 /* If got here, then the syntax allows intervals. */
2498 /* At least (most) this many matches must be made. */
2499 int lower_bound = -1, upper_bound = -1;
2501 beg_interval = p - 1;
2505 if (syntax & RE_NO_BK_BRACES)
2506 goto unfetch_interval;
2508 FREE_STACK_RETURN (REG_EBRACE);
2511 GET_UNSIGNED_NUMBER (lower_bound);
2515 GET_UNSIGNED_NUMBER (upper_bound);
2516 if (upper_bound < 0) upper_bound = RE_DUP_MAX;
2519 /* Interval such as `{1}' => match exactly once. */
2520 upper_bound = lower_bound;
2522 if (lower_bound < 0 || upper_bound > RE_DUP_MAX
2523 || lower_bound > upper_bound)
2525 if (syntax & RE_NO_BK_BRACES)
2526 goto unfetch_interval;
2528 FREE_STACK_RETURN (REG_BADBR);
2531 if (!(syntax & RE_NO_BK_BRACES))
2533 if (c != '\\') FREE_STACK_RETURN (REG_EBRACE);
2540 if (syntax & RE_NO_BK_BRACES)
2541 goto unfetch_interval;
2543 FREE_STACK_RETURN (REG_BADBR);
2546 /* We just parsed a valid interval. */
2548 /* If it's invalid to have no preceding re. */
2551 if (syntax & RE_CONTEXT_INVALID_OPS)
2552 FREE_STACK_RETURN (REG_BADRPT);
2553 else if (syntax & RE_CONTEXT_INDEP_OPS)
2556 goto unfetch_interval;
2559 /* If the upper bound is zero, don't want to succeed at
2560 all; jump from `laststart' to `b + 3', which will be
2561 the end of the buffer after we insert the jump. */
2562 if (upper_bound == 0)
2564 GET_BUFFER_SPACE (3);
2565 INSERT_JUMP (jump, laststart, b + 3);
2569 /* Otherwise, we have a nontrivial interval. When
2570 we're all done, the pattern will look like:
2571 set_number_at <jump count> <upper bound>
2572 set_number_at <succeed_n count> <lower bound>
2573 succeed_n <after jump addr> <succeed_n count>
2575 jump_n <succeed_n addr> <jump count>
2576 (The upper bound and `jump_n' are omitted if
2577 `upper_bound' is 1, though.) */
2579 { /* If the upper bound is > 1, we need to insert
2580 more at the end of the loop. */
2581 unsigned nbytes = 10 + (upper_bound > 1) * 10;
2583 GET_BUFFER_SPACE (nbytes);
2585 /* Initialize lower bound of the `succeed_n', even
2586 though it will be set during matching by its
2587 attendant `set_number_at' (inserted next),
2588 because `re_compile_fastmap' needs to know.
2589 Jump to the `jump_n' we might insert below. */
2590 INSERT_JUMP2 (succeed_n, laststart,
2591 b + 5 + (upper_bound > 1) * 5,
2595 /* Code to initialize the lower bound. Insert
2596 before the `succeed_n'. The `5' is the last two
2597 bytes of this `set_number_at', plus 3 bytes of
2598 the following `succeed_n'. */
2599 insert_op2 (set_number_at, laststart, 5, lower_bound, b);
2602 if (upper_bound > 1)
2603 { /* More than one repetition is allowed, so
2604 append a backward jump to the `succeed_n'
2605 that starts this interval.
2607 When we've reached this during matching,
2608 we'll have matched the interval once, so
2609 jump back only `upper_bound - 1' times. */
2610 STORE_JUMP2 (jump_n, b, laststart + 5,
2614 /* The location we want to set is the second
2615 parameter of the `jump_n'; that is `b-2' as
2616 an absolute address. `laststart' will be
2617 the `set_number_at' we're about to insert;
2618 `laststart+3' the number to set, the source
2619 for the relative address. But we are
2620 inserting into the middle of the pattern --
2621 so everything is getting moved up by 5.
2622 Conclusion: (b - 2) - (laststart + 3) + 5,
2623 i.e., b - laststart.
2625 We insert this at the beginning of the loop
2626 so that if we fail during matching, we'll
2627 reinitialize the bounds. */
2628 insert_op2 (set_number_at, laststart, b - laststart,
2629 upper_bound - 1, b);
2634 beg_interval = NULL;
2639 /* If an invalid interval, match the characters as literals. */
2640 assert (beg_interval);
2642 beg_interval = NULL;
2644 /* normal_char and normal_backslash need `c'. */
2647 if (!(syntax & RE_NO_BK_BRACES))
2649 if (p > pattern && p[-1] == '\\')
2650 goto normal_backslash;
2655 /* There is no way to specify the before_dot and after_dot
2656 operators. rms says this is ok. --karl */
2664 BUF_PUSH_2 (syntaxspec, syntax_spec_code[c]);
2670 BUF_PUSH_2 (notsyntaxspec, syntax_spec_code[c]);
2676 if (syntax & RE_NO_GNU_OPS)
2679 BUF_PUSH (wordchar);
2684 if (syntax & RE_NO_GNU_OPS)
2687 BUF_PUSH (notwordchar);
2692 if (syntax & RE_NO_GNU_OPS)
2698 if (syntax & RE_NO_GNU_OPS)
2704 if (syntax & RE_NO_GNU_OPS)
2706 BUF_PUSH (wordbound);
2710 if (syntax & RE_NO_GNU_OPS)
2712 BUF_PUSH (notwordbound);
2716 if (syntax & RE_NO_GNU_OPS)
2722 if (syntax & RE_NO_GNU_OPS)
2727 case '1': case '2': case '3': case '4': case '5':
2728 case '6': case '7': case '8': case '9':
2729 if (syntax & RE_NO_BK_REFS)
2735 FREE_STACK_RETURN (REG_ESUBREG);
2737 /* Can't back reference to a subexpression if inside of it. */
2738 if (group_in_compile_stack (compile_stack, (regnum_t) c1))
2742 BUF_PUSH_2 (duplicate, c1);
2748 if (syntax & RE_BK_PLUS_QM)
2751 goto normal_backslash;
2755 /* You might think it would be useful for \ to mean
2756 not to translate; but if we don't translate it
2757 it will never match anything. */
2765 /* Expects the character in `c'. */
2767 /* If no exactn currently being built. */
2770 /* If last exactn not at current position. */
2771 || pending_exact + *pending_exact + 1 != b
2773 /* We have only one byte following the exactn for the count. */
2774 || *pending_exact == (1 << BYTEWIDTH) - 1
2776 /* If followed by a repetition operator. */
2777 || *p == '*' || *p == '^'
2778 || ((syntax & RE_BK_PLUS_QM)
2779 ? *p == '\\' && (p[1] == '+' || p[1] == '?')
2780 : (*p == '+' || *p == '?'))
2781 || ((syntax & RE_INTERVALS)
2782 && ((syntax & RE_NO_BK_BRACES)
2784 : (p[0] == '\\' && p[1] == '{'))))
2786 /* Start building a new exactn. */
2790 BUF_PUSH_2 (exactn, 0);
2791 pending_exact = b - 1;
2798 } /* while p != pend */
2801 /* Through the pattern now. */
2804 STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
2806 if (!COMPILE_STACK_EMPTY)
2807 FREE_STACK_RETURN (REG_EPAREN);
2809 /* If we don't want backtracking, force success
2810 the first time we reach the end of the compiled pattern. */
2811 if (syntax & RE_NO_POSIX_BACKTRACKING)
2814 free (compile_stack.stack);
2816 /* We have succeeded; set the length of the buffer. */
2817 bufp->used = b - bufp->buffer;
2822 DEBUG_PRINT1 ("\nCompiled pattern: \n");
2823 print_compiled_pattern (bufp);
2827 #ifndef MATCH_MAY_ALLOCATE
2828 /* Initialize the failure stack to the largest possible stack. This
2829 isn't necessary unless we're trying to avoid calling alloca in
2830 the search and match routines. */
2832 int num_regs = bufp->re_nsub + 1;
2834 /* Since DOUBLE_FAIL_STACK refuses to double only if the current size
2835 is strictly greater than re_max_failures, the largest possible stack
2836 is 2 * re_max_failures failure points. */
2837 if (fail_stack.size < (2 * re_max_failures * MAX_FAILURE_ITEMS))
2839 fail_stack.size = (2 * re_max_failures * MAX_FAILURE_ITEMS);
2842 if (! fail_stack.stack)
2844 = (fail_stack_elt_t *) xmalloc (fail_stack.size
2845 * sizeof (fail_stack_elt_t));
2848 = (fail_stack_elt_t *) xrealloc (fail_stack.stack,
2850 * sizeof (fail_stack_elt_t)));
2851 # else /* not emacs */
2852 if (! fail_stack.stack)
2854 = (fail_stack_elt_t *) malloc (fail_stack.size
2855 * sizeof (fail_stack_elt_t));
2858 = (fail_stack_elt_t *) realloc (fail_stack.stack,
2860 * sizeof (fail_stack_elt_t)));
2861 # endif /* not emacs */
2864 regex_grow_registers (num_regs);
2866 #endif /* not MATCH_MAY_ALLOCATE */
2869 } /* regex_compile */
2871 /* Subroutines for `regex_compile'. */
2873 /* Store OP at LOC followed by two-byte integer parameter ARG. */
2876 store_op1 (op, loc, arg)
2881 *loc = (unsigned char) op;
2882 STORE_NUMBER (loc + 1, arg);
2886 /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
2889 store_op2 (op, loc, arg1, arg2)
2894 *loc = (unsigned char) op;
2895 STORE_NUMBER (loc + 1, arg1);
2896 STORE_NUMBER (loc + 3, arg2);
2900 /* Copy the bytes from LOC to END to open up three bytes of space at LOC
2901 for OP followed by two-byte integer parameter ARG. */
2904 insert_op1 (op, loc, arg, end)
2910 register unsigned char *pfrom = end;
2911 register unsigned char *pto = end + 3;
2913 while (pfrom != loc)
2916 store_op1 (op, loc, arg);
2920 /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
2923 insert_op2 (op, loc, arg1, arg2, end)
2929 register unsigned char *pfrom = end;
2930 register unsigned char *pto = end + 5;
2932 while (pfrom != loc)
2935 store_op2 (op, loc, arg1, arg2);
2939 /* P points to just after a ^ in PATTERN. Return true if that ^ comes
2940 after an alternative or a begin-subexpression. We assume there is at
2941 least one character before the ^. */
2944 at_begline_loc_p (pattern, p, syntax)
2945 const char *pattern, *p;
2946 reg_syntax_t syntax;
2948 const char *prev = p - 2;
2949 boolean prev_prev_backslash = prev > pattern && prev[-1] == '\\';
2952 /* After a subexpression? */
2953 (*prev == '(' && (syntax & RE_NO_BK_PARENS || prev_prev_backslash))
2954 /* After an alternative? */
2955 || (*prev == '|' && (syntax & RE_NO_BK_VBAR || prev_prev_backslash));
2959 /* The dual of at_begline_loc_p. This one is for $. We assume there is
2960 at least one character after the $, i.e., `P < PEND'. */
2963 at_endline_loc_p (p, pend, syntax)
2964 const char *p, *pend;
2965 reg_syntax_t syntax;
2967 const char *next = p;
2968 boolean next_backslash = *next == '\\';
2969 const char *next_next = p + 1 < pend ? p + 1 : 0;
2972 /* Before a subexpression? */
2973 (syntax & RE_NO_BK_PARENS ? *next == ')'
2974 : next_backslash && next_next && *next_next == ')')
2975 /* Before an alternative? */
2976 || (syntax & RE_NO_BK_VBAR ? *next == '|'
2977 : next_backslash && next_next && *next_next == '|');
2981 /* Returns true if REGNUM is in one of COMPILE_STACK's elements and
2982 false if it's not. */
2985 group_in_compile_stack (compile_stack, regnum)
2986 compile_stack_type compile_stack;
2991 for (this_element = compile_stack.avail - 1;
2994 if (compile_stack.stack[this_element].regnum == regnum)
3001 /* Read the ending character of a range (in a bracket expression) from the
3002 uncompiled pattern *P_PTR (which ends at PEND). We assume the
3003 starting character is in `P[-2]'. (`P[-1]' is the character `-'.)
3004 Then we set the translation of all bits between the starting and
3005 ending characters (inclusive) in the compiled pattern B.
3007 Return an error code.
3009 We use these short variable names so we can use the same macros as
3010 `regex_compile' itself. */
3012 static reg_errcode_t
3013 compile_range (p_ptr, pend, translate, syntax, b)
3014 const char **p_ptr, *pend;
3015 RE_TRANSLATE_TYPE translate;
3016 reg_syntax_t syntax;
3021 const char *p = *p_ptr;
3022 unsigned int range_start, range_end;
3027 /* Even though the pattern is a signed `char *', we need to fetch
3028 with unsigned char *'s; if the high bit of the pattern character
3029 is set, the range endpoints will be negative if we fetch using a
3032 We also want to fetch the endpoints without translating them; the
3033 appropriate translation is done in the bit-setting loop below. */
3034 /* The SVR4 compiler on the 3B2 had trouble with unsigned const char *. */
3035 range_start = ((const unsigned char *) p)[-2];
3036 range_end = ((const unsigned char *) p)[0];
3038 /* Have to increment the pointer into the pattern string, so the
3039 caller isn't still at the ending character. */
3042 /* If the start is after the end, the range is empty. */
3043 if (range_start > range_end)
3044 return syntax & RE_NO_EMPTY_RANGES ? REG_ERANGE : REG_NOERROR;
3046 /* Here we see why `this_char' has to be larger than an `unsigned
3047 char' -- the range is inclusive, so if `range_end' == 0xff
3048 (assuming 8-bit characters), we would otherwise go into an infinite
3049 loop, since all characters <= 0xff. */
3050 for (this_char = range_start; this_char <= range_end; this_char++)
3052 SET_LIST_BIT (TRANSLATE (this_char));
3058 /* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
3059 BUFP. A fastmap records which of the (1 << BYTEWIDTH) possible
3060 characters can start a string that matches the pattern. This fastmap
3061 is used by re_search to skip quickly over impossible starting points.
3063 The caller must supply the address of a (1 << BYTEWIDTH)-byte data
3064 area as BUFP->fastmap.
3066 We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
3069 Returns 0 if we succeed, -2 if an internal error. */
3072 re_compile_fastmap (bufp)
3073 struct re_pattern_buffer *bufp;
3076 #ifdef MATCH_MAY_ALLOCATE
3077 fail_stack_type fail_stack;
3079 #ifndef REGEX_MALLOC
3083 register char *fastmap = bufp->fastmap;
3084 unsigned char *pattern = bufp->buffer;
3085 unsigned char *p = pattern;
3086 register unsigned char *pend = pattern + bufp->used;
3089 /* This holds the pointer to the failure stack, when
3090 it is allocated relocatably. */
3091 fail_stack_elt_t *failure_stack_ptr;
3094 /* Assume that each path through the pattern can be null until
3095 proven otherwise. We set this false at the bottom of switch
3096 statement, to which we get only if a particular path doesn't
3097 match the empty string. */
3098 boolean path_can_be_null = true;
3100 /* We aren't doing a `succeed_n' to begin with. */
3101 boolean succeed_n_p = false;
3103 assert (fastmap != NULL && p != NULL);
3106 bzero (fastmap, 1 << BYTEWIDTH); /* Assume nothing's valid. */
3107 bufp->fastmap_accurate = 1; /* It will be when we're done. */
3108 bufp->can_be_null = 0;
3112 if (p == pend || *p == succeed)
3114 /* We have reached the (effective) end of pattern. */
3115 if (!FAIL_STACK_EMPTY ())
3117 bufp->can_be_null |= path_can_be_null;
3119 /* Reset for next path. */
3120 path_can_be_null = true;
3122 p = fail_stack.stack[--fail_stack.avail].pointer;
3130 /* We should never be about to go beyond the end of the pattern. */
3133 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
3136 /* I guess the idea here is to simply not bother with a fastmap
3137 if a backreference is used, since it's too hard to figure out
3138 the fastmap for the corresponding group. Setting
3139 `can_be_null' stops `re_search_2' from using the fastmap, so
3140 that is all we do. */
3142 bufp->can_be_null = 1;
3146 /* Following are the cases which match a character. These end
3155 for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
3156 if (p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH)))
3162 /* Chars beyond end of map must be allowed. */
3163 for (j = *p * BYTEWIDTH; j < (1 << BYTEWIDTH); j++)
3166 for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
3167 if (!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))))
3173 for (j = 0; j < (1 << BYTEWIDTH); j++)
3174 if (SYNTAX (j) == Sword)
3180 for (j = 0; j < (1 << BYTEWIDTH); j++)
3181 if (SYNTAX (j) != Sword)
3188 int fastmap_newline = fastmap['\n'];
3190 /* `.' matches anything ... */
3191 for (j = 0; j < (1 << BYTEWIDTH); j++)
3194 /* ... except perhaps newline. */
3195 if (!(bufp->syntax & RE_DOT_NEWLINE))
3196 fastmap['\n'] = fastmap_newline;
3198 /* Return if we have already set `can_be_null'; if we have,
3199 then the fastmap is irrelevant. Something's wrong here. */
3200 else if (bufp->can_be_null)
3203 /* Otherwise, have to check alternative paths. */
3210 for (j = 0; j < (1 << BYTEWIDTH); j++)
3211 if (SYNTAX (j) == (enum syntaxcode) k)
3218 for (j = 0; j < (1 << BYTEWIDTH); j++)
3219 if (SYNTAX (j) != (enum syntaxcode) k)
3224 /* All cases after this match the empty string. These end with
3244 case push_dummy_failure:
3249 case pop_failure_jump:
3250 case maybe_pop_jump:
3253 case dummy_failure_jump:
3254 EXTRACT_NUMBER_AND_INCR (j, p);
3259 /* Jump backward implies we just went through the body of a
3260 loop and matched nothing. Opcode jumped to should be
3261 `on_failure_jump' or `succeed_n'. Just treat it like an
3262 ordinary jump. For a * loop, it has pushed its failure
3263 point already; if so, discard that as redundant. */
3264 if ((re_opcode_t) *p != on_failure_jump
3265 && (re_opcode_t) *p != succeed_n)
3269 EXTRACT_NUMBER_AND_INCR (j, p);
3272 /* If what's on the stack is where we are now, pop it. */
3273 if (!FAIL_STACK_EMPTY ()
3274 && fail_stack.stack[fail_stack.avail - 1].pointer == p)
3280 case on_failure_jump:
3281 case on_failure_keep_string_jump:
3282 handle_on_failure_jump:
3283 EXTRACT_NUMBER_AND_INCR (j, p);
3285 /* For some patterns, e.g., `(a?)?', `p+j' here points to the
3286 end of the pattern. We don't want to push such a point,
3287 since when we restore it above, entering the switch will
3288 increment `p' past the end of the pattern. We don't need
3289 to push such a point since we obviously won't find any more
3290 fastmap entries beyond `pend'. Such a pattern can match
3291 the null string, though. */
3294 if (!PUSH_PATTERN_OP (p + j, fail_stack))
3296 RESET_FAIL_STACK ();
3301 bufp->can_be_null = 1;
3305 EXTRACT_NUMBER_AND_INCR (k, p); /* Skip the n. */
3306 succeed_n_p = false;
3313 /* Get to the number of times to succeed. */
3316 /* Increment p past the n for when k != 0. */
3317 EXTRACT_NUMBER_AND_INCR (k, p);
3321 succeed_n_p = true; /* Spaghetti code alert. */
3322 goto handle_on_failure_jump;
3339 abort (); /* We have listed all the cases. */
3342 /* Getting here means we have found the possible starting
3343 characters for one path of the pattern -- and that the empty
3344 string does not match. We need not follow this path further.
3345 Instead, look at the next alternative (remembered on the
3346 stack), or quit if no more. The test at the top of the loop
3347 does these things. */
3348 path_can_be_null = false;
3352 /* Set `can_be_null' for the last path (also the first path, if the
3353 pattern is empty). */
3354 bufp->can_be_null |= path_can_be_null;
3357 RESET_FAIL_STACK ();
3359 } /* re_compile_fastmap */
3361 weak_alias (__re_compile_fastmap, re_compile_fastmap)
3364 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
3365 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
3366 this memory for recording register information. STARTS and ENDS
3367 must be allocated using the malloc library routine, and must each
3368 be at least NUM_REGS * sizeof (regoff_t) bytes long.
3370 If NUM_REGS == 0, then subsequent matches should allocate their own
3373 Unless this function is called, the first search or match using
3374 PATTERN_BUFFER will allocate its own register data, without
3375 freeing the old data. */
3378 re_set_registers (bufp, regs, num_regs, starts, ends)
3379 struct re_pattern_buffer *bufp;
3380 struct re_registers *regs;
3382 regoff_t *starts, *ends;
3386 bufp->regs_allocated = REGS_REALLOCATE;
3387 regs->num_regs = num_regs;
3388 regs->start = starts;
3393 bufp->regs_allocated = REGS_UNALLOCATED;
3395 regs->start = regs->end = (regoff_t *) 0;
3399 weak_alias (__re_set_registers, re_set_registers)
3402 /* Searching routines. */
3404 /* Like re_search_2, below, but only one string is specified, and
3405 doesn't let you say where to stop matching. */
3408 re_search (bufp, string, size, startpos, range, regs)
3409 struct re_pattern_buffer *bufp;
3411 int size, startpos, range;
3412 struct re_registers *regs;
3414 return re_search_2 (bufp, NULL, 0, string, size, startpos, range,
3418 weak_alias (__re_search, re_search)
3422 /* Using the compiled pattern in BUFP->buffer, first tries to match the
3423 virtual concatenation of STRING1 and STRING2, starting first at index
3424 STARTPOS, then at STARTPOS + 1, and so on.
3426 STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
3428 RANGE is how far to scan while trying to match. RANGE = 0 means try
3429 only at STARTPOS; in general, the last start tried is STARTPOS +
3432 In REGS, return the indices of the virtual concatenation of STRING1
3433 and STRING2 that matched the entire BUFP->buffer and its contained
3436 Do not consider matching one past the index STOP in the virtual
3437 concatenation of STRING1 and STRING2.
3439 We return either the position in the strings at which the match was
3440 found, -1 if no match, or -2 if error (such as failure
3444 re_search_2 (bufp, string1, size1, string2, size2, startpos, range, regs, stop)
3445 struct re_pattern_buffer *bufp;
3446 const char *string1, *string2;
3450 struct re_registers *regs;
3454 register char *fastmap = bufp->fastmap;
3455 register RE_TRANSLATE_TYPE translate = bufp->translate;
3456 int total_size = size1 + size2;
3457 int endpos = startpos + range;
3459 /* Check for out-of-range STARTPOS. */
3460 if (startpos < 0 || startpos > total_size)
3463 /* Fix up RANGE if it might eventually take us outside
3464 the virtual concatenation of STRING1 and STRING2.
3465 Make sure we won't move STARTPOS below 0 or above TOTAL_SIZE. */
3467 range = 0 - startpos;
3468 else if (endpos > total_size)
3469 range = total_size - startpos;
3471 /* If the search isn't to be a backwards one, don't waste time in a
3472 search for a pattern that must be anchored. */
3473 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == begbuf && range > 0)
3482 /* In a forward search for something that starts with \=.
3483 don't keep searching past point. */
3484 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == at_dot && range > 0)
3486 range = PT - startpos;
3492 /* Update the fastmap now if not correct already. */
3493 if (fastmap && !bufp->fastmap_accurate)
3494 if (re_compile_fastmap (bufp) == -2)
3497 /* Loop through the string, looking for a place to start matching. */
3500 /* If a fastmap is supplied, skip quickly over characters that
3501 cannot be the start of a match. If the pattern can match the
3502 null string, however, we don't need to skip characters; we want
3503 the first null string. */
3504 if (fastmap && startpos < total_size && !bufp->can_be_null)
3506 if (range > 0) /* Searching forwards. */
3508 register const char *d;
3509 register int lim = 0;
3512 if (startpos < size1 && startpos + range >= size1)
3513 lim = range - (size1 - startpos);
3515 d = (startpos >= size1 ? string2 - size1 : string1) + startpos;
3517 /* Written out as an if-else to avoid testing `translate'
3521 && !fastmap[(unsigned char)
3522 translate[(unsigned char) *d++]])
3525 while (range > lim && !fastmap[(unsigned char) *d++])
3528 startpos += irange - range;
3530 else /* Searching backwards. */
3532 register char c = (size1 == 0 || startpos >= size1
3533 ? string2[startpos - size1]
3534 : string1[startpos]);
3536 if (!fastmap[(unsigned char) TRANSLATE (c)])
3541 /* If can't match the null string, and that's all we have left, fail. */
3542 if (range >= 0 && startpos == total_size && fastmap
3543 && !bufp->can_be_null)
3546 val = re_match_2_internal (bufp, string1, size1, string2, size2,
3547 startpos, regs, stop);
3548 #ifndef REGEX_MALLOC
3577 weak_alias (__re_search_2, re_search_2)
3580 /* This converts PTR, a pointer into one of the search strings `string1'
3581 and `string2' into an offset from the beginning of that string. */
3582 #define POINTER_TO_OFFSET(ptr) \
3583 (FIRST_STRING_P (ptr) \
3584 ? ((regoff_t) ((ptr) - string1)) \
3585 : ((regoff_t) ((ptr) - string2 + size1)))
3587 /* Macros for dealing with the split strings in re_match_2. */
3589 #define MATCHING_IN_FIRST_STRING (dend == end_match_1)
3591 /* Call before fetching a character with *d. This switches over to
3592 string2 if necessary. */
3593 #define PREFETCH() \
3596 /* End of string2 => fail. */ \
3597 if (dend == end_match_2) \
3599 /* End of string1 => advance to string2. */ \
3601 dend = end_match_2; \
3605 /* Test if at very beginning or at very end of the virtual concatenation
3606 of `string1' and `string2'. If only one string, it's `string2'. */
3607 #define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
3608 #define AT_STRINGS_END(d) ((d) == end2)
3611 /* Test if D points to a character which is word-constituent. We have
3612 two special cases to check for: if past the end of string1, look at
3613 the first character in string2; and if before the beginning of
3614 string2, look at the last character in string1. */
3615 #define WORDCHAR_P(d) \
3616 (SYNTAX ((d) == end1 ? *string2 \
3617 : (d) == string2 - 1 ? *(end1 - 1) : *(d)) \
3620 /* Disabled due to a compiler bug -- see comment at case wordbound */
3622 /* Test if the character before D and the one at D differ with respect
3623 to being word-constituent. */
3624 #define AT_WORD_BOUNDARY(d) \
3625 (AT_STRINGS_BEG (d) || AT_STRINGS_END (d) \
3626 || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
3629 /* Free everything we malloc. */
3630 #ifdef MATCH_MAY_ALLOCATE
3631 # define FREE_VAR(var) if (var) REGEX_FREE (var); var = NULL
3632 # define FREE_VARIABLES() \
3634 REGEX_FREE_STACK (fail_stack.stack); \
3635 FREE_VAR (regstart); \
3636 FREE_VAR (regend); \
3637 FREE_VAR (old_regstart); \
3638 FREE_VAR (old_regend); \
3639 FREE_VAR (best_regstart); \
3640 FREE_VAR (best_regend); \
3641 FREE_VAR (reg_info); \
3642 FREE_VAR (reg_dummy); \
3643 FREE_VAR (reg_info_dummy); \
3646 # define FREE_VARIABLES() ((void)0) /* Do nothing! But inhibit gcc warning. */
3647 #endif /* not MATCH_MAY_ALLOCATE */
3649 /* These values must meet several constraints. They must not be valid
3650 register values; since we have a limit of 255 registers (because
3651 we use only one byte in the pattern for the register number), we can
3652 use numbers larger than 255. They must differ by 1, because of
3653 NUM_FAILURE_ITEMS above. And the value for the lowest register must
3654 be larger than the value for the highest register, so we do not try
3655 to actually save any registers when none are active. */
3656 #define NO_HIGHEST_ACTIVE_REG (1 << BYTEWIDTH)
3657 #define NO_LOWEST_ACTIVE_REG (NO_HIGHEST_ACTIVE_REG + 1)
3659 /* Matching routines. */
3661 #ifndef emacs /* Emacs never uses this. */
3662 /* re_match is like re_match_2 except it takes only a single string. */
3665 re_match (bufp, string, size, pos, regs)
3666 struct re_pattern_buffer *bufp;
3669 struct re_registers *regs;
3671 int result = re_match_2_internal (bufp, NULL, 0, string, size,
3673 # ifndef REGEX_MALLOC
3681 weak_alias (__re_match, re_match)
3683 #endif /* not emacs */
3685 static boolean group_match_null_string_p _RE_ARGS ((unsigned char **p,
3687 register_info_type *reg_info));
3688 static boolean alt_match_null_string_p _RE_ARGS ((unsigned char *p,
3690 register_info_type *reg_info));
3691 static boolean common_op_match_null_string_p _RE_ARGS ((unsigned char **p,
3693 register_info_type *reg_info));
3694 static int bcmp_translate _RE_ARGS ((const char *s1, const char *s2,
3695 int len, char *translate));
3697 /* re_match_2 matches the compiled pattern in BUFP against the
3698 the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
3699 and SIZE2, respectively). We start matching at POS, and stop
3702 If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
3703 store offsets for the substring each group matched in REGS. See the
3704 documentation for exactly how many groups we fill.
3706 We return -1 if no match, -2 if an internal error (such as the
3707 failure stack overflowing). Otherwise, we return the length of the
3708 matched substring. */
3711 re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
3712 struct re_pattern_buffer *bufp;
3713 const char *string1, *string2;
3716 struct re_registers *regs;
3719 int result = re_match_2_internal (bufp, string1, size1, string2, size2,
3721 #ifndef REGEX_MALLOC
3729 weak_alias (__re_match_2, re_match_2)
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;
3835 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3836 const char **best_regstart, **best_regend;
3839 /* Logically, this is `best_regend[0]'. But we don't want to have to
3840 allocate space for that if we're not allocating space for anything
3841 else (see below). Also, we never need info about register 0 for
3842 any of the other register vectors, and it seems rather a kludge to
3843 treat `best_regend' differently than the rest. So we keep track of
3844 the end of the best match so far in a separate variable. We
3845 initialize this to NULL so that when we backtrack the first time
3846 and need to test it, it's not garbage. */
3847 const char *match_end = NULL;
3849 /* This helps SET_REGS_MATCHED avoid doing redundant work. */
3850 int set_regs_matched_done = 0;
3852 /* Used when we pop values we don't care about. */
3853 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3854 const char **reg_dummy;
3855 register_info_type *reg_info_dummy;
3859 /* Counts the total number of registers pushed. */
3860 unsigned num_regs_pushed = 0;
3863 DEBUG_PRINT1 ("\n\nEntering re_match_2.\n");
3867 #ifdef MATCH_MAY_ALLOCATE
3868 /* Do not bother to initialize all the register variables if there are
3869 no groups in the pattern, as it takes a fair amount of time. If
3870 there are groups, we include space for register 0 (the whole
3871 pattern), even though we never use it, since it simplifies the
3872 array indexing. We should fix this. */
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 *);
3881 reg_info = REGEX_TALLOC (num_regs, register_info_type);
3882 reg_dummy = REGEX_TALLOC (num_regs, const char *);
3883 reg_info_dummy = REGEX_TALLOC (num_regs, register_info_type);
3885 if (!(regstart && regend && old_regstart && old_regend && reg_info
3886 && 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)
3909 /* Initialize subexpression text positions to -1 to mark ones that no
3910 start_memory/stop_memory has been seen for. Also initialize the
3911 register information struct. */
3912 for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++)
3914 regstart[mcnt] = regend[mcnt]
3915 = old_regstart[mcnt] = old_regend[mcnt] = REG_UNSET_VALUE;
3917 REG_MATCH_NULL_STRING_P (reg_info[mcnt]) = MATCH_NULL_UNSET_VALUE;
3918 IS_ACTIVE (reg_info[mcnt]) = 0;
3919 MATCHED_SOMETHING (reg_info[mcnt]) = 0;
3920 EVER_MATCHED_SOMETHING (reg_info[mcnt]) = 0;
3923 /* We move `string1' into `string2' if the latter's empty -- but not if
3924 `string1' is null. */
3925 if (size2 == 0 && string1 != NULL)
3932 end1 = string1 + size1;
3933 end2 = string2 + size2;
3935 /* Compute where to stop matching, within the two strings. */
3938 end_match_1 = string1 + stop;
3939 end_match_2 = string2;
3944 end_match_2 = string2 + stop - size1;
3947 /* `p' scans through the pattern as `d' scans through the data.
3948 `dend' is the end of the input string that `d' points within. `d'
3949 is advanced into the following input string whenever necessary, but
3950 this happens before fetching; therefore, at the beginning of the
3951 loop, `d' can be pointing at the end of a string, but it cannot
3953 if (size1 > 0 && pos <= size1)
3960 d = string2 + pos - size1;
3964 DEBUG_PRINT1 ("The compiled pattern is:\n");
3965 DEBUG_PRINT_COMPILED_PATTERN (bufp, p, pend);
3966 DEBUG_PRINT1 ("The string to match is: `");
3967 DEBUG_PRINT_DOUBLE_STRING (d, string1, size1, string2, size2);
3968 DEBUG_PRINT1 ("'\n");
3970 /* This loops over pattern commands. It exits by returning from the
3971 function if the match is complete, or it drops through if the match
3972 fails at this starting point in the input data. */
3976 DEBUG_PRINT2 ("\n%p: ", p);
3978 DEBUG_PRINT2 ("\n0x%x: ", p);
3982 { /* End of pattern means we might have succeeded. */
3983 DEBUG_PRINT1 ("end of pattern ... ");
3985 /* If we haven't matched the entire string, and we want the
3986 longest match, try backtracking. */
3987 if (d != end_match_2)
3989 /* 1 if this match ends in the same string (string1 or string2)
3990 as the best previous match. */
3991 boolean same_str_p = (FIRST_STRING_P (match_end)
3992 == MATCHING_IN_FIRST_STRING);
3993 /* 1 if this match is the best seen so far. */
3994 boolean best_match_p;
3996 /* AIX compiler got confused when this was combined
3997 with the previous declaration. */
3999 best_match_p = d > match_end;
4001 best_match_p = !MATCHING_IN_FIRST_STRING;
4003 DEBUG_PRINT1 ("backtracking.\n");
4005 if (!FAIL_STACK_EMPTY ())
4006 { /* More failure points to try. */
4008 /* If exceeds best match so far, save it. */
4009 if (!best_regs_set || best_match_p)
4011 best_regs_set = true;
4014 DEBUG_PRINT1 ("\nSAVING match as best so far.\n");
4016 for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++)
4018 best_regstart[mcnt] = regstart[mcnt];
4019 best_regend[mcnt] = regend[mcnt];
4025 /* If no failure points, don't restore garbage. And if
4026 last match is real best match, don't restore second
4028 else if (best_regs_set && !best_match_p)
4031 /* Restore best match. It may happen that `dend ==
4032 end_match_1' while the restored d is in string2.
4033 For example, the pattern `x.*y.*z' against the
4034 strings `x-' and `y-z-', if the two strings are
4035 not consecutive in memory. */
4036 DEBUG_PRINT1 ("Restoring best registers.\n");
4039 dend = ((d >= string1 && d <= end1)
4040 ? end_match_1 : end_match_2);
4042 for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++)
4044 regstart[mcnt] = best_regstart[mcnt];
4045 regend[mcnt] = best_regend[mcnt];
4048 } /* d != end_match_2 */
4051 DEBUG_PRINT1 ("Accepting match.\n");
4053 /* If caller wants register contents data back, do it. */
4054 if (regs && !bufp->no_sub)
4056 /* Have the register data arrays been allocated? */
4057 if (bufp->regs_allocated == REGS_UNALLOCATED)
4058 { /* No. So allocate them with malloc. We need one
4059 extra element beyond `num_regs' for the `-1' marker
4061 regs->num_regs = MAX (RE_NREGS, num_regs + 1);
4062 regs->start = TALLOC (regs->num_regs, regoff_t);
4063 regs->end = TALLOC (regs->num_regs, regoff_t);
4064 if (regs->start == NULL || regs->end == NULL)
4069 bufp->regs_allocated = REGS_REALLOCATE;
4071 else if (bufp->regs_allocated == REGS_REALLOCATE)
4072 { /* Yes. If we need more elements than were already
4073 allocated, reallocate them. If we need fewer, just
4075 if (regs->num_regs < num_regs + 1)
4077 regs->num_regs = num_regs + 1;
4078 RETALLOC (regs->start, regs->num_regs, regoff_t);
4079 RETALLOC (regs->end, regs->num_regs, regoff_t);
4080 if (regs->start == NULL || regs->end == NULL)
4089 /* These braces fend off a "empty body in an else-statement"
4090 warning under GCC when assert expands to nothing. */
4091 assert (bufp->regs_allocated == REGS_FIXED);
4094 /* Convert the pointer data in `regstart' and `regend' to
4095 indices. Register zero has to be set differently,
4096 since we haven't kept track of any info for it. */
4097 if (regs->num_regs > 0)
4099 regs->start[0] = pos;
4100 regs->end[0] = (MATCHING_IN_FIRST_STRING
4101 ? ((regoff_t) (d - string1))
4102 : ((regoff_t) (d - string2 + size1)));
4105 /* Go through the first `min (num_regs, regs->num_regs)'
4106 registers, since that is all we initialized. */
4107 for (mcnt = 1; (unsigned) mcnt < MIN (num_regs, regs->num_regs);
4110 if (REG_UNSET (regstart[mcnt]) || REG_UNSET (regend[mcnt]))
4111 regs->start[mcnt] = regs->end[mcnt] = -1;
4115 = (regoff_t) POINTER_TO_OFFSET (regstart[mcnt]);
4117 = (regoff_t) POINTER_TO_OFFSET (regend[mcnt]);
4121 /* If the regs structure we return has more elements than
4122 were in the pattern, set the extra elements to -1. If
4123 we (re)allocated the registers, this is the case,
4124 because we always allocate enough to have at least one
4126 for (mcnt = num_regs; (unsigned) mcnt < regs->num_regs; mcnt++)
4127 regs->start[mcnt] = regs->end[mcnt] = -1;
4128 } /* regs && !bufp->no_sub */
4130 DEBUG_PRINT4 ("%u failure points pushed, %u popped (%u remain).\n",
4131 nfailure_points_pushed, nfailure_points_popped,
4132 nfailure_points_pushed - nfailure_points_popped);
4133 DEBUG_PRINT2 ("%u registers pushed.\n", num_regs_pushed);
4135 mcnt = d - pos - (MATCHING_IN_FIRST_STRING
4139 DEBUG_PRINT2 ("Returning %d from re_match_2.\n", mcnt);
4145 /* Otherwise match next pattern command. */
4146 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
4148 /* Ignore these. Used to ignore the n of succeed_n's which
4149 currently have n == 0. */
4151 DEBUG_PRINT1 ("EXECUTING no_op.\n");
4155 DEBUG_PRINT1 ("EXECUTING succeed.\n");
4158 /* Match the next n pattern characters exactly. The following
4159 byte in the pattern defines n, and the n bytes after that
4160 are the characters to match. */
4163 DEBUG_PRINT2 ("EXECUTING exactn %d.\n", mcnt);
4165 /* This is written out as an if-else so we don't waste time
4166 testing `translate' inside the loop. */
4172 if ((unsigned char) translate[(unsigned char) *d++]
4173 != (unsigned char) *p++)
4183 if (*d++ != (char) *p++) goto fail;
4187 SET_REGS_MATCHED ();
4191 /* Match any character except possibly a newline or a null. */
4193 DEBUG_PRINT1 ("EXECUTING anychar.\n");
4197 if ((!(bufp->syntax & RE_DOT_NEWLINE) && TRANSLATE (*d) == '\n')
4198 || (bufp->syntax & RE_DOT_NOT_NULL && TRANSLATE (*d) == '\000'))
4201 SET_REGS_MATCHED ();
4202 DEBUG_PRINT2 (" Matched `%d'.\n", *d);
4210 register unsigned char c;
4211 boolean not = (re_opcode_t) *(p - 1) == charset_not;
4213 DEBUG_PRINT2 ("EXECUTING charset%s.\n", not ? "_not" : "");
4216 c = TRANSLATE (*d); /* The character to match. */
4218 /* Cast to `unsigned' instead of `unsigned char' in case the
4219 bit list is a full 32 bytes long. */
4220 if (c < (unsigned) (*p * BYTEWIDTH)
4221 && p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4226 if (!not) goto fail;
4228 SET_REGS_MATCHED ();
4234 /* The beginning of a group is represented by start_memory.
4235 The arguments are the register number in the next byte, and the
4236 number of groups inner to this one in the next. The text
4237 matched within the group is recorded (in the internal
4238 registers data structure) under the register number. */
4240 DEBUG_PRINT3 ("EXECUTING start_memory %d (%d):\n", *p, p[1]);
4242 /* Find out if this group can match the empty string. */
4243 p1 = p; /* To send to group_match_null_string_p. */
4245 if (REG_MATCH_NULL_STRING_P (reg_info[*p]) == MATCH_NULL_UNSET_VALUE)
4246 REG_MATCH_NULL_STRING_P (reg_info[*p])
4247 = group_match_null_string_p (&p1, pend, reg_info);
4249 /* Save the position in the string where we were the last time
4250 we were at this open-group operator in case the group is
4251 operated upon by a repetition operator, e.g., with `(a*)*b'
4252 against `ab'; then we want to ignore where we are now in
4253 the string in case this attempt to match fails. */
4254 old_regstart[*p] = REG_MATCH_NULL_STRING_P (reg_info[*p])
4255 ? REG_UNSET (regstart[*p]) ? d : regstart[*p]
4257 DEBUG_PRINT2 (" old_regstart: %d\n",
4258 POINTER_TO_OFFSET (old_regstart[*p]));
4261 DEBUG_PRINT2 (" regstart: %d\n", POINTER_TO_OFFSET (regstart[*p]));
4263 IS_ACTIVE (reg_info[*p]) = 1;
4264 MATCHED_SOMETHING (reg_info[*p]) = 0;
4266 /* Clear this whenever we change the register activity status. */
4267 set_regs_matched_done = 0;
4269 /* This is the new highest active register. */
4270 highest_active_reg = *p;
4272 /* If nothing was active before, this is the new lowest active
4274 if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
4275 lowest_active_reg = *p;
4277 /* Move past the register number and inner group count. */
4279 just_past_start_mem = p;
4284 /* The stop_memory opcode represents the end of a group. Its
4285 arguments are the same as start_memory's: the register
4286 number, and the number of inner groups. */
4288 DEBUG_PRINT3 ("EXECUTING stop_memory %d (%d):\n", *p, p[1]);
4290 /* We need to save the string position the last time we were at
4291 this close-group operator in case the group is operated
4292 upon by a repetition operator, e.g., with `((a*)*(b*)*)*'
4293 against `aba'; then we want to ignore where we are now in
4294 the string in case this attempt to match fails. */
4295 old_regend[*p] = REG_MATCH_NULL_STRING_P (reg_info[*p])
4296 ? REG_UNSET (regend[*p]) ? d : regend[*p]
4298 DEBUG_PRINT2 (" old_regend: %d\n",
4299 POINTER_TO_OFFSET (old_regend[*p]));
4302 DEBUG_PRINT2 (" regend: %d\n", POINTER_TO_OFFSET (regend[*p]));
4304 /* This register isn't active anymore. */
4305 IS_ACTIVE (reg_info[*p]) = 0;
4307 /* Clear this whenever we change the register activity status. */
4308 set_regs_matched_done = 0;
4310 /* If this was the only register active, nothing is active
4312 if (lowest_active_reg == highest_active_reg)
4314 lowest_active_reg = NO_LOWEST_ACTIVE_REG;
4315 highest_active_reg = NO_HIGHEST_ACTIVE_REG;
4318 { /* We must scan for the new highest active register, since
4319 it isn't necessarily one less than now: consider
4320 (a(b)c(d(e)f)g). When group 3 ends, after the f), the
4321 new highest active register is 1. */
4322 unsigned char r = *p - 1;
4323 while (r > 0 && !IS_ACTIVE (reg_info[r]))
4326 /* If we end up at register zero, that means that we saved
4327 the registers as the result of an `on_failure_jump', not
4328 a `start_memory', and we jumped to past the innermost
4329 `stop_memory'. For example, in ((.)*) we save
4330 registers 1 and 2 as a result of the *, but when we pop
4331 back to the second ), we are at the stop_memory 1.
4332 Thus, nothing is active. */
4335 lowest_active_reg = NO_LOWEST_ACTIVE_REG;
4336 highest_active_reg = NO_HIGHEST_ACTIVE_REG;
4339 highest_active_reg = r;
4342 /* If just failed to match something this time around with a
4343 group that's operated on by a repetition operator, try to
4344 force exit from the ``loop'', and restore the register
4345 information for this group that we had before trying this
4347 if ((!MATCHED_SOMETHING (reg_info[*p])
4348 || just_past_start_mem == p - 1)
4351 boolean is_a_jump_n = false;
4355 switch ((re_opcode_t) *p1++)
4359 case pop_failure_jump:
4360 case maybe_pop_jump:
4362 case dummy_failure_jump:
4363 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4373 /* If the next operation is a jump backwards in the pattern
4374 to an on_failure_jump right before the start_memory
4375 corresponding to this stop_memory, exit from the loop
4376 by forcing a failure after pushing on the stack the
4377 on_failure_jump's jump in the pattern, and d. */
4378 if (mcnt < 0 && (re_opcode_t) *p1 == on_failure_jump
4379 && (re_opcode_t) p1[3] == start_memory && p1[4] == *p)
4381 /* If this group ever matched anything, then restore
4382 what its registers were before trying this last
4383 failed match, e.g., with `(a*)*b' against `ab' for
4384 regstart[1], and, e.g., with `((a*)*(b*)*)*'
4385 against `aba' for regend[3].
4387 Also restore the registers for inner groups for,
4388 e.g., `((a*)(b*))*' against `aba' (register 3 would
4389 otherwise get trashed). */
4391 if (EVER_MATCHED_SOMETHING (reg_info[*p]))
4395 EVER_MATCHED_SOMETHING (reg_info[*p]) = 0;
4397 /* Restore this and inner groups' (if any) registers. */
4398 for (r = *p; r < (unsigned) *p + (unsigned) *(p + 1);
4401 regstart[r] = old_regstart[r];
4403 /* xx why this test? */
4404 if (old_regend[r] >= regstart[r])
4405 regend[r] = old_regend[r];
4409 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4410 PUSH_FAILURE_POINT (p1 + mcnt, d, -2);
4416 /* Move past the register number and the inner group count. */
4421 /* \<digit> has been turned into a `duplicate' command which is
4422 followed by the numeric value of <digit> as the register number. */
4425 register const char *d2, *dend2;
4426 int regno = *p++; /* Get which register to match against. */
4427 DEBUG_PRINT2 ("EXECUTING duplicate %d.\n", regno);
4429 /* Can't back reference a group which we've never matched. */
4430 if (REG_UNSET (regstart[regno]) || REG_UNSET (regend[regno]))
4433 /* Where in input to try to start matching. */
4434 d2 = regstart[regno];
4436 /* Where to stop matching; if both the place to start and
4437 the place to stop matching are in the same string, then
4438 set to the place to stop, otherwise, for now have to use
4439 the end of the first string. */
4441 dend2 = ((FIRST_STRING_P (regstart[regno])
4442 == FIRST_STRING_P (regend[regno]))
4443 ? regend[regno] : end_match_1);
4446 /* If necessary, advance to next segment in register
4450 if (dend2 == end_match_2) break;
4451 if (dend2 == regend[regno]) break;
4453 /* End of string1 => advance to string2. */
4455 dend2 = regend[regno];
4457 /* At end of register contents => success */
4458 if (d2 == dend2) break;
4460 /* If necessary, advance to next segment in data. */
4463 /* How many characters left in this segment to match. */
4466 /* Want how many consecutive characters we can match in
4467 one shot, so, if necessary, adjust the count. */
4468 if (mcnt > dend2 - d2)
4471 /* Compare that many; failure if mismatch, else move
4474 ? bcmp_translate (d, d2, mcnt, translate)
4475 : memcmp (d, d2, mcnt))
4477 d += mcnt, d2 += mcnt;
4479 /* Do this because we've match some characters. */
4480 SET_REGS_MATCHED ();
4486 /* begline matches the empty string at the beginning of the string
4487 (unless `not_bol' is set in `bufp'), and, if
4488 `newline_anchor' is set, after newlines. */
4490 DEBUG_PRINT1 ("EXECUTING begline.\n");
4492 if (AT_STRINGS_BEG (d))
4494 if (!bufp->not_bol) break;
4496 else if (d[-1] == '\n' && bufp->newline_anchor)
4500 /* In all other cases, we fail. */
4504 /* endline is the dual of begline. */
4506 DEBUG_PRINT1 ("EXECUTING endline.\n");
4508 if (AT_STRINGS_END (d))
4510 if (!bufp->not_eol) break;
4513 /* We have to ``prefetch'' the next character. */
4514 else if ((d == end1 ? *string2 : *d) == '\n'
4515 && bufp->newline_anchor)
4522 /* Match at the very beginning of the data. */
4524 DEBUG_PRINT1 ("EXECUTING begbuf.\n");
4525 if (AT_STRINGS_BEG (d))
4530 /* Match at the very end of the data. */
4532 DEBUG_PRINT1 ("EXECUTING endbuf.\n");
4533 if (AT_STRINGS_END (d))
4538 /* on_failure_keep_string_jump is used to optimize `.*\n'. It
4539 pushes NULL as the value for the string on the stack. Then
4540 `pop_failure_point' will keep the current value for the
4541 string, instead of restoring it. To see why, consider
4542 matching `foo\nbar' against `.*\n'. The .* matches the foo;
4543 then the . fails against the \n. But the next thing we want
4544 to do is match the \n against the \n; if we restored the
4545 string value, we would be back at the foo.
4547 Because this is used only in specific cases, we don't need to
4548 check all the things that `on_failure_jump' does, to make
4549 sure the right things get saved on the stack. Hence we don't
4550 share its code. The only reason to push anything on the
4551 stack at all is that otherwise we would have to change
4552 `anychar's code to do something besides goto fail in this
4553 case; that seems worse than this. */
4554 case on_failure_keep_string_jump:
4555 DEBUG_PRINT1 ("EXECUTING on_failure_keep_string_jump");
4557 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4559 DEBUG_PRINT3 (" %d (to %p):\n", mcnt, p + mcnt);
4561 DEBUG_PRINT3 (" %d (to 0x%x):\n", mcnt, p + mcnt);
4564 PUSH_FAILURE_POINT (p + mcnt, NULL, -2);
4568 /* Uses of on_failure_jump:
4570 Each alternative starts with an on_failure_jump that points
4571 to the beginning of the next alternative. Each alternative
4572 except the last ends with a jump that in effect jumps past
4573 the rest of the alternatives. (They really jump to the
4574 ending jump of the following alternative, because tensioning
4575 these jumps is a hassle.)
4577 Repeats start with an on_failure_jump that points past both
4578 the repetition text and either the following jump or
4579 pop_failure_jump back to this on_failure_jump. */
4580 case on_failure_jump:
4582 DEBUG_PRINT1 ("EXECUTING on_failure_jump");
4584 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4586 DEBUG_PRINT3 (" %d (to %p)", mcnt, p + mcnt);
4588 DEBUG_PRINT3 (" %d (to 0x%x)", mcnt, p + mcnt);
4591 /* If this on_failure_jump comes right before a group (i.e.,
4592 the original * applied to a group), save the information
4593 for that group and all inner ones, so that if we fail back
4594 to this point, the group's information will be correct.
4595 For example, in \(a*\)*\1, we need the preceding group,
4596 and in \(zz\(a*\)b*\)\2, we need the inner group. */
4598 /* We can't use `p' to check ahead because we push
4599 a failure point to `p + mcnt' after we do this. */
4602 /* We need to skip no_op's before we look for the
4603 start_memory in case this on_failure_jump is happening as
4604 the result of a completed succeed_n, as in \(a\)\{1,3\}b\1
4606 while (p1 < pend && (re_opcode_t) *p1 == no_op)
4609 if (p1 < pend && (re_opcode_t) *p1 == start_memory)
4611 /* We have a new highest active register now. This will
4612 get reset at the start_memory we are about to get to,
4613 but we will have saved all the registers relevant to
4614 this repetition op, as described above. */
4615 highest_active_reg = *(p1 + 1) + *(p1 + 2);
4616 if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
4617 lowest_active_reg = *(p1 + 1);
4620 DEBUG_PRINT1 (":\n");
4621 PUSH_FAILURE_POINT (p + mcnt, d, -2);
4625 /* A smart repeat ends with `maybe_pop_jump'.
4626 We change it to either `pop_failure_jump' or `jump'. */
4627 case maybe_pop_jump:
4628 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4629 DEBUG_PRINT2 ("EXECUTING maybe_pop_jump %d.\n", mcnt);
4631 register unsigned char *p2 = p;
4633 /* Compare the beginning of the repeat with what in the
4634 pattern follows its end. If we can establish that there
4635 is nothing that they would both match, i.e., that we
4636 would have to backtrack because of (as in, e.g., `a*a')
4637 then we can change to pop_failure_jump, because we'll
4638 never have to backtrack.
4640 This is not true in the case of alternatives: in
4641 `(a|ab)*' we do need to backtrack to the `ab' alternative
4642 (e.g., if the string was `ab'). But instead of trying to
4643 detect that here, the alternative has put on a dummy
4644 failure point which is what we will end up popping. */
4646 /* Skip over open/close-group commands.
4647 If what follows this loop is a ...+ construct,
4648 look at what begins its body, since we will have to
4649 match at least one of that. */
4653 && ((re_opcode_t) *p2 == stop_memory
4654 || (re_opcode_t) *p2 == start_memory))
4656 else if (p2 + 6 < pend
4657 && (re_opcode_t) *p2 == dummy_failure_jump)
4664 /* p1[0] ... p1[2] are the `on_failure_jump' corresponding
4665 to the `maybe_finalize_jump' of this case. Examine what
4668 /* If we're at the end of the pattern, we can change. */
4671 /* Consider what happens when matching ":\(.*\)"
4672 against ":/". I don't really understand this code
4674 p[-3] = (unsigned char) pop_failure_jump;
4676 (" End of pattern: change to `pop_failure_jump'.\n");
4679 else if ((re_opcode_t) *p2 == exactn
4680 || (bufp->newline_anchor && (re_opcode_t) *p2 == endline))
4682 register unsigned char c
4683 = *p2 == (unsigned char) endline ? '\n' : p2[2];
4685 if ((re_opcode_t) p1[3] == exactn && p1[5] != c)
4687 p[-3] = (unsigned char) pop_failure_jump;
4688 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n",
4692 else if ((re_opcode_t) p1[3] == charset
4693 || (re_opcode_t) p1[3] == charset_not)
4695 int not = (re_opcode_t) p1[3] == charset_not;
4697 if (c < (unsigned char) (p1[4] * BYTEWIDTH)
4698 && p1[5 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4701 /* `not' is equal to 1 if c would match, which means
4702 that we can't change to pop_failure_jump. */
4705 p[-3] = (unsigned char) pop_failure_jump;
4706 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4710 else if ((re_opcode_t) *p2 == charset)
4713 register unsigned char c
4714 = *p2 == (unsigned char) endline ? '\n' : p2[2];
4718 if ((re_opcode_t) p1[3] == exactn
4719 && ! ((int) p2[1] * BYTEWIDTH > (int) p1[5]
4720 && (p2[2 + p1[5] / BYTEWIDTH]
4721 & (1 << (p1[5] % BYTEWIDTH)))))
4723 if ((re_opcode_t) p1[3] == exactn
4724 && ! ((int) p2[1] * BYTEWIDTH > (int) p1[4]
4725 && (p2[2 + p1[4] / BYTEWIDTH]
4726 & (1 << (p1[4] % BYTEWIDTH)))))
4729 p[-3] = (unsigned char) pop_failure_jump;
4730 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n",
4734 else if ((re_opcode_t) p1[3] == charset_not)
4737 /* We win if the charset_not inside the loop
4738 lists every character listed in the charset after. */
4739 for (idx = 0; idx < (int) p2[1]; idx++)
4740 if (! (p2[2 + idx] == 0
4741 || (idx < (int) p1[4]
4742 && ((p2[2 + idx] & ~ p1[5 + idx]) == 0))))
4747 p[-3] = (unsigned char) pop_failure_jump;
4748 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4751 else if ((re_opcode_t) p1[3] == charset)
4754 /* We win if the charset inside the loop
4755 has no overlap with the one after the loop. */
4757 idx < (int) p2[1] && idx < (int) p1[4];
4759 if ((p2[2 + idx] & p1[5 + idx]) != 0)
4762 if (idx == p2[1] || idx == p1[4])
4764 p[-3] = (unsigned char) pop_failure_jump;
4765 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4770 p -= 2; /* Point at relative address again. */
4771 if ((re_opcode_t) p[-1] != pop_failure_jump)
4773 p[-1] = (unsigned char) jump;
4774 DEBUG_PRINT1 (" Match => jump.\n");
4775 goto unconditional_jump;
4777 /* Note fall through. */
4780 /* The end of a simple repeat has a pop_failure_jump back to
4781 its matching on_failure_jump, where the latter will push a
4782 failure point. The pop_failure_jump takes off failure
4783 points put on by this pop_failure_jump's matching
4784 on_failure_jump; we got through the pattern to here from the
4785 matching on_failure_jump, so didn't fail. */
4786 case pop_failure_jump:
4788 /* We need to pass separate storage for the lowest and
4789 highest registers, even though we don't care about the
4790 actual values. Otherwise, we will restore only one
4791 register from the stack, since lowest will == highest in
4792 `pop_failure_point'. */
4793 active_reg_t dummy_low_reg, dummy_high_reg;
4794 unsigned char *pdummy;
4797 DEBUG_PRINT1 ("EXECUTING pop_failure_jump.\n");
4798 POP_FAILURE_POINT (sdummy, pdummy,
4799 dummy_low_reg, dummy_high_reg,
4800 reg_dummy, reg_dummy, reg_info_dummy);
4802 /* Note fall through. */
4806 DEBUG_PRINT2 ("\n%p: ", p);
4808 DEBUG_PRINT2 ("\n0x%x: ", p);
4810 /* Note fall through. */
4812 /* Unconditionally jump (without popping any failure points). */
4814 EXTRACT_NUMBER_AND_INCR (mcnt, p); /* Get the amount to jump. */
4815 DEBUG_PRINT2 ("EXECUTING jump %d ", mcnt);
4816 p += mcnt; /* Do the jump. */
4818 DEBUG_PRINT2 ("(to %p).\n", p);
4820 DEBUG_PRINT2 ("(to 0x%x).\n", p);
4825 /* We need this opcode so we can detect where alternatives end
4826 in `group_match_null_string_p' et al. */
4828 DEBUG_PRINT1 ("EXECUTING jump_past_alt.\n");
4829 goto unconditional_jump;
4832 /* Normally, the on_failure_jump pushes a failure point, which
4833 then gets popped at pop_failure_jump. We will end up at
4834 pop_failure_jump, also, and with a pattern of, say, `a+', we
4835 are skipping over the on_failure_jump, so we have to push
4836 something meaningless for pop_failure_jump to pop. */
4837 case dummy_failure_jump:
4838 DEBUG_PRINT1 ("EXECUTING dummy_failure_jump.\n");
4839 /* It doesn't matter what we push for the string here. What
4840 the code at `fail' tests is the value for the pattern. */
4841 PUSH_FAILURE_POINT (NULL, NULL, -2);
4842 goto unconditional_jump;
4845 /* At the end of an alternative, we need to push a dummy failure
4846 point in case we are followed by a `pop_failure_jump', because
4847 we don't want the failure point for the alternative to be
4848 popped. For example, matching `(a|ab)*' against `aab'
4849 requires that we match the `ab' alternative. */
4850 case push_dummy_failure:
4851 DEBUG_PRINT1 ("EXECUTING push_dummy_failure.\n");
4852 /* See comments just above at `dummy_failure_jump' about the
4854 PUSH_FAILURE_POINT (NULL, NULL, -2);
4857 /* Have to succeed matching what follows at least n times.
4858 After that, handle like `on_failure_jump'. */
4860 EXTRACT_NUMBER (mcnt, p + 2);
4861 DEBUG_PRINT2 ("EXECUTING succeed_n %d.\n", mcnt);
4864 /* Originally, this is how many times we HAVE to succeed. */
4869 STORE_NUMBER_AND_INCR (p, mcnt);
4871 DEBUG_PRINT3 (" Setting %p to %d.\n", p - 2, mcnt);
4873 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p - 2, mcnt);
4879 DEBUG_PRINT2 (" Setting two bytes from %p to no_op.\n", p+2);
4881 DEBUG_PRINT2 (" Setting two bytes from 0x%x to no_op.\n", p+2);
4883 p[2] = (unsigned char) no_op;
4884 p[3] = (unsigned char) no_op;
4890 EXTRACT_NUMBER (mcnt, p + 2);
4891 DEBUG_PRINT2 ("EXECUTING jump_n %d.\n", mcnt);
4893 /* Originally, this is how many times we CAN jump. */
4897 STORE_NUMBER (p + 2, mcnt);
4899 DEBUG_PRINT3 (" Setting %p to %d.\n", p + 2, mcnt);
4901 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p + 2, mcnt);
4903 goto unconditional_jump;
4905 /* If don't have to jump any more, skip over the rest of command. */
4912 DEBUG_PRINT1 ("EXECUTING set_number_at.\n");
4914 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4916 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4918 DEBUG_PRINT3 (" Setting %p to %d.\n", p1, mcnt);
4920 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p1, mcnt);
4922 STORE_NUMBER (p1, mcnt);
4927 /* The DEC Alpha C compiler 3.x generates incorrect code for the
4928 test WORDCHAR_P (d - 1) != WORDCHAR_P (d) in the expansion of
4929 AT_WORD_BOUNDARY, so this code is disabled. Expanding the
4930 macro and introducing temporary variables works around the bug. */
4933 DEBUG_PRINT1 ("EXECUTING wordbound.\n");
4934 if (AT_WORD_BOUNDARY (d))
4939 DEBUG_PRINT1 ("EXECUTING notwordbound.\n");
4940 if (AT_WORD_BOUNDARY (d))
4946 boolean prevchar, thischar;
4948 DEBUG_PRINT1 ("EXECUTING wordbound.\n");
4949 if (AT_STRINGS_BEG (d) || AT_STRINGS_END (d))
4952 prevchar = WORDCHAR_P (d - 1);
4953 thischar = WORDCHAR_P (d);
4954 if (prevchar != thischar)
4961 boolean prevchar, thischar;
4963 DEBUG_PRINT1 ("EXECUTING notwordbound.\n");
4964 if (AT_STRINGS_BEG (d) || AT_STRINGS_END (d))
4967 prevchar = WORDCHAR_P (d - 1);
4968 thischar = WORDCHAR_P (d);
4969 if (prevchar != thischar)
4976 DEBUG_PRINT1 ("EXECUTING wordbeg.\n");
4977 if (WORDCHAR_P (d) && (AT_STRINGS_BEG (d) || !WORDCHAR_P (d - 1)))
4982 DEBUG_PRINT1 ("EXECUTING wordend.\n");
4983 if (!AT_STRINGS_BEG (d) && WORDCHAR_P (d - 1)
4984 && (!WORDCHAR_P (d) || AT_STRINGS_END (d)))
4990 DEBUG_PRINT1 ("EXECUTING before_dot.\n");
4991 if (PTR_CHAR_POS ((unsigned char *) d) >= point)
4996 DEBUG_PRINT1 ("EXECUTING at_dot.\n");
4997 if (PTR_CHAR_POS ((unsigned char *) d) != point)
5002 DEBUG_PRINT1 ("EXECUTING after_dot.\n");
5003 if (PTR_CHAR_POS ((unsigned char *) d) <= point)
5008 DEBUG_PRINT2 ("EXECUTING syntaxspec %d.\n", mcnt);
5013 DEBUG_PRINT1 ("EXECUTING Emacs wordchar.\n");
5017 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
5019 if (SYNTAX (d[-1]) != (enum syntaxcode) mcnt)
5021 SET_REGS_MATCHED ();
5025 DEBUG_PRINT2 ("EXECUTING notsyntaxspec %d.\n", mcnt);
5027 goto matchnotsyntax;
5030 DEBUG_PRINT1 ("EXECUTING Emacs notwordchar.\n");
5034 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
5036 if (SYNTAX (d[-1]) == (enum syntaxcode) mcnt)
5038 SET_REGS_MATCHED ();
5041 #else /* not emacs */
5043 DEBUG_PRINT1 ("EXECUTING non-Emacs wordchar.\n");
5045 if (!WORDCHAR_P (d))
5047 SET_REGS_MATCHED ();
5052 DEBUG_PRINT1 ("EXECUTING non-Emacs notwordchar.\n");
5056 SET_REGS_MATCHED ();
5059 #endif /* not emacs */
5064 continue; /* Successfully executed one pattern command; keep going. */
5067 /* We goto here if a matching operation fails. */
5069 if (!FAIL_STACK_EMPTY ())
5070 { /* A restart point is known. Restore to that state. */
5071 DEBUG_PRINT1 ("\nFAIL:\n");
5072 POP_FAILURE_POINT (d, p,
5073 lowest_active_reg, highest_active_reg,
5074 regstart, regend, reg_info);
5076 /* If this failure point is a dummy, try the next one. */
5080 /* If we failed to the end of the pattern, don't examine *p. */
5084 boolean is_a_jump_n = false;
5086 /* If failed to a backwards jump that's part of a repetition
5087 loop, need to pop this failure point and use the next one. */
5088 switch ((re_opcode_t) *p)
5092 case maybe_pop_jump:
5093 case pop_failure_jump:
5096 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5099 if ((is_a_jump_n && (re_opcode_t) *p1 == succeed_n)
5101 && (re_opcode_t) *p1 == on_failure_jump))
5109 if (d >= string1 && d <= end1)
5113 break; /* Matching at this starting point really fails. */
5117 goto restore_best_regs;
5121 return -1; /* Failure to match. */
5124 /* Subroutine definitions for re_match_2. */
5127 /* We are passed P pointing to a register number after a start_memory.
5129 Return true if the pattern up to the corresponding stop_memory can
5130 match the empty string, and false otherwise.
5132 If we find the matching stop_memory, sets P to point to one past its number.
5133 Otherwise, sets P to an undefined byte less than or equal to END.
5135 We don't handle duplicates properly (yet). */
5138 group_match_null_string_p (p, end, reg_info)
5139 unsigned char **p, *end;
5140 register_info_type *reg_info;
5143 /* Point to after the args to the start_memory. */
5144 unsigned char *p1 = *p + 2;
5148 /* Skip over opcodes that can match nothing, and return true or
5149 false, as appropriate, when we get to one that can't, or to the
5150 matching stop_memory. */
5152 switch ((re_opcode_t) *p1)
5154 /* Could be either a loop or a series of alternatives. */
5155 case on_failure_jump:
5157 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5159 /* If the next operation is not a jump backwards in the
5164 /* Go through the on_failure_jumps of the alternatives,
5165 seeing if any of the alternatives cannot match nothing.
5166 The last alternative starts with only a jump,
5167 whereas the rest start with on_failure_jump and end
5168 with a jump, e.g., here is the pattern for `a|b|c':
5170 /on_failure_jump/0/6/exactn/1/a/jump_past_alt/0/6
5171 /on_failure_jump/0/6/exactn/1/b/jump_past_alt/0/3
5174 So, we have to first go through the first (n-1)
5175 alternatives and then deal with the last one separately. */
5178 /* Deal with the first (n-1) alternatives, which start
5179 with an on_failure_jump (see above) that jumps to right
5180 past a jump_past_alt. */
5182 while ((re_opcode_t) p1[mcnt-3] == jump_past_alt)
5184 /* `mcnt' holds how many bytes long the alternative
5185 is, including the ending `jump_past_alt' and
5188 if (!alt_match_null_string_p (p1, p1 + mcnt - 3,
5192 /* Move to right after this alternative, including the
5196 /* Break if it's the beginning of an n-th alternative
5197 that doesn't begin with an on_failure_jump. */
5198 if ((re_opcode_t) *p1 != on_failure_jump)
5201 /* Still have to check that it's not an n-th
5202 alternative that starts with an on_failure_jump. */
5204 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5205 if ((re_opcode_t) p1[mcnt-3] != jump_past_alt)
5207 /* Get to the beginning of the n-th alternative. */
5213 /* Deal with the last alternative: go back and get number
5214 of the `jump_past_alt' just before it. `mcnt' contains
5215 the length of the alternative. */
5216 EXTRACT_NUMBER (mcnt, p1 - 2);
5218 if (!alt_match_null_string_p (p1, p1 + mcnt, reg_info))
5221 p1 += mcnt; /* Get past the n-th alternative. */
5227 assert (p1[1] == **p);
5233 if (!common_op_match_null_string_p (&p1, end, reg_info))
5236 } /* while p1 < end */
5239 } /* group_match_null_string_p */
5242 /* Similar to group_match_null_string_p, but doesn't deal with alternatives:
5243 It expects P to be the first byte of a single alternative and END one
5244 byte past the last. The alternative can contain groups. */
5247 alt_match_null_string_p (p, end, reg_info)
5248 unsigned char *p, *end;
5249 register_info_type *reg_info;
5252 unsigned char *p1 = p;
5256 /* Skip over opcodes that can match nothing, and break when we get
5257 to one that can't. */
5259 switch ((re_opcode_t) *p1)
5262 case on_failure_jump:
5264 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5269 if (!common_op_match_null_string_p (&p1, end, reg_info))
5272 } /* while p1 < end */
5275 } /* alt_match_null_string_p */
5278 /* Deals with the ops common to group_match_null_string_p and
5279 alt_match_null_string_p.
5281 Sets P to one after the op and its arguments, if any. */
5284 common_op_match_null_string_p (p, end, reg_info)
5285 unsigned char **p, *end;
5286 register_info_type *reg_info;
5291 unsigned char *p1 = *p;
5293 switch ((re_opcode_t) *p1++)
5313 assert (reg_no > 0 && reg_no <= MAX_REGNUM);
5314 ret = group_match_null_string_p (&p1, end, reg_info);
5316 /* Have to set this here in case we're checking a group which
5317 contains a group and a back reference to it. */
5319 if (REG_MATCH_NULL_STRING_P (reg_info[reg_no]) == MATCH_NULL_UNSET_VALUE)
5320 REG_MATCH_NULL_STRING_P (reg_info[reg_no]) = ret;
5326 /* If this is an optimized succeed_n for zero times, make the jump. */
5328 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5336 /* Get to the number of times to succeed. */
5338 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5343 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5351 if (!REG_MATCH_NULL_STRING_P (reg_info[*p1]))
5359 /* All other opcodes mean we cannot match the empty string. */
5365 } /* common_op_match_null_string_p */
5368 /* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
5369 bytes; nonzero otherwise. */
5372 bcmp_translate (s1, s2, len, translate)
5373 const char *s1, *s2;
5375 RE_TRANSLATE_TYPE translate;
5377 register const unsigned char *p1 = (const unsigned char *) s1;
5378 register const unsigned char *p2 = (const unsigned char *) s2;
5381 if (translate[*p1++] != translate[*p2++]) return 1;
5387 /* Entry points for GNU code. */
5389 /* re_compile_pattern is the GNU regular expression compiler: it
5390 compiles PATTERN (of length SIZE) and puts the result in BUFP.
5391 Returns 0 if the pattern was valid, otherwise an error string.
5393 Assumes the `allocated' (and perhaps `buffer') and `translate' fields
5394 are set in BUFP on entry.
5396 We call regex_compile to do the actual compilation. */
5399 re_compile_pattern (pattern, length, bufp)
5400 const char *pattern;
5402 struct re_pattern_buffer *bufp;
5406 /* GNU code is written to assume at least RE_NREGS registers will be set
5407 (and at least one extra will be -1). */
5408 bufp->regs_allocated = REGS_UNALLOCATED;
5410 /* And GNU code determines whether or not to get register information
5411 by passing null for the REGS argument to re_match, etc., not by
5415 /* Match anchors at newline. */
5416 bufp->newline_anchor = 1;
5418 ret = regex_compile (pattern, length, re_syntax_options, bufp);
5422 return gettext (re_error_msgid[(int) ret]);
5425 weak_alias (__re_compile_pattern, re_compile_pattern)
5428 /* Entry points compatible with 4.2 BSD regex library. We don't define
5429 them unless specifically requested. */
5431 #if defined _REGEX_RE_COMP || defined _LIBC
5433 /* BSD has one and only one pattern buffer. */
5434 static struct re_pattern_buffer re_comp_buf;
5438 /* Make these definitions weak in libc, so POSIX programs can redefine
5439 these names if they don't use our functions, and still use
5440 regcomp/regexec below without link errors. */
5450 if (!re_comp_buf.buffer)
5451 return gettext ("No previous regular expression");
5455 if (!re_comp_buf.buffer)
5457 re_comp_buf.buffer = (unsigned char *) malloc (200);
5458 if (re_comp_buf.buffer == NULL)
5459 return (char *) gettext (re_error_msgid[(int) REG_ESPACE]);
5460 re_comp_buf.allocated = 200;
5462 re_comp_buf.fastmap = (char *) malloc (1 << BYTEWIDTH);
5463 if (re_comp_buf.fastmap == NULL)
5464 return (char *) gettext (re_error_msgid[(int) REG_ESPACE]);
5467 /* Since `re_exec' always passes NULL for the `regs' argument, we
5468 don't need to initialize the pattern buffer fields which affect it. */
5470 /* Match anchors at newlines. */
5471 re_comp_buf.newline_anchor = 1;
5473 ret = regex_compile (s, strlen (s), re_syntax_options, &re_comp_buf);
5478 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
5479 return (char *) gettext (re_error_msgid[(int) ret]);
5490 const int len = strlen (s);
5492 0 <= re_search (&re_comp_buf, s, len, 0, len, (struct re_registers *) 0);
5495 #endif /* _REGEX_RE_COMP */
5497 /* POSIX.2 functions. Don't define these for Emacs. */
5501 /* regcomp takes a regular expression as a string and compiles it.
5503 PREG is a regex_t *. We do not expect any fields to be initialized,
5504 since POSIX says we shouldn't. Thus, we set
5506 `buffer' to the compiled pattern;
5507 `used' to the length of the compiled pattern;
5508 `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
5509 REG_EXTENDED bit in CFLAGS is set; otherwise, to
5510 RE_SYNTAX_POSIX_BASIC;
5511 `newline_anchor' to REG_NEWLINE being set in CFLAGS;
5512 `fastmap' to an allocated space for the fastmap;
5513 `fastmap_accurate' to 1;
5514 `re_nsub' to the number of subexpressions in PATTERN.
5516 PATTERN is the address of the pattern string.
5518 CFLAGS is a series of bits which affect compilation.
5520 If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
5521 use POSIX basic syntax.
5523 If REG_NEWLINE is set, then . and [^...] don't match newline.
5524 Also, regexec will try a match beginning after every newline.
5526 If REG_ICASE is set, then we considers upper- and lowercase
5527 versions of letters to be equivalent when matching.
5529 If REG_NOSUB is set, then when PREG is passed to regexec, that
5530 routine will report only success or failure, and nothing about the
5533 It returns 0 if it succeeds, nonzero if it doesn't. (See gnu-regex.h for
5534 the return codes and their meanings.) */
5537 regcomp (preg, pattern, cflags)
5539 const char *pattern;
5544 = (cflags & REG_EXTENDED) ?
5545 RE_SYNTAX_POSIX_EXTENDED : RE_SYNTAX_POSIX_BASIC;
5547 /* regex_compile will allocate the space for the compiled pattern. */
5549 preg->allocated = 0;
5552 /* Try to allocate space for the fastmap. */
5553 preg->fastmap = (char *) malloc (1 << BYTEWIDTH);
5555 if (cflags & REG_ICASE)
5560 = (RE_TRANSLATE_TYPE) malloc (CHAR_SET_SIZE
5561 * sizeof (*(RE_TRANSLATE_TYPE)0));
5562 if (preg->translate == NULL)
5563 return (int) REG_ESPACE;
5565 /* Map uppercase characters to corresponding lowercase ones. */
5566 for (i = 0; i < CHAR_SET_SIZE; i++)
5567 preg->translate[i] = TOLOWER (i);
5570 preg->translate = NULL;
5572 /* If REG_NEWLINE is set, newlines are treated differently. */
5573 if (cflags & REG_NEWLINE)
5574 { /* REG_NEWLINE implies neither . nor [^...] match newline. */
5575 syntax &= ~RE_DOT_NEWLINE;
5576 syntax |= RE_HAT_LISTS_NOT_NEWLINE;
5577 /* It also changes the matching behavior. */
5578 preg->newline_anchor = 1;
5581 preg->newline_anchor = 0;
5583 preg->no_sub = !!(cflags & REG_NOSUB);
5585 /* POSIX says a null character in the pattern terminates it, so we
5586 can use strlen here in compiling the pattern. */
5587 ret = regex_compile (pattern, strlen (pattern), syntax, preg);
5589 /* POSIX doesn't distinguish between an unmatched open-group and an
5590 unmatched close-group: both are REG_EPAREN. */
5591 if (ret == REG_ERPAREN) ret = REG_EPAREN;
5593 if (ret == REG_NOERROR && preg->fastmap)
5595 /* Compute the fastmap now, since regexec cannot modify the pattern
5597 if (re_compile_fastmap (preg) == -2)
5599 /* Some error occured while computing the fastmap, just forget
5601 free (preg->fastmap);
5602 preg->fastmap = NULL;
5609 weak_alias (__regcomp, regcomp)
5613 /* regexec searches for a given pattern, specified by PREG, in the
5616 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
5617 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
5618 least NMATCH elements, and we set them to the offsets of the
5619 corresponding matched substrings.
5621 EFLAGS specifies `execution flags' which affect matching: if
5622 REG_NOTBOL is set, then ^ does not match at the beginning of the
5623 string; if REG_NOTEOL is set, then $ does not match at the end.
5625 We return 0 if we find a match and REG_NOMATCH if not. */
5628 regexec (preg, string, nmatch, pmatch, eflags)
5629 const regex_t *preg;
5632 regmatch_t pmatch[];
5636 struct re_registers regs;
5637 regex_t private_preg;
5638 int len = strlen (string);
5639 boolean want_reg_info = !preg->no_sub && nmatch > 0;
5641 private_preg = *preg;
5643 private_preg.not_bol = !!(eflags & REG_NOTBOL);
5644 private_preg.not_eol = !!(eflags & REG_NOTEOL);
5646 /* The user has told us exactly how many registers to return
5647 information about, via `nmatch'. We have to pass that on to the
5648 matching routines. */
5649 private_preg.regs_allocated = REGS_FIXED;
5653 regs.num_regs = nmatch;
5654 regs.start = TALLOC (nmatch, regoff_t);
5655 regs.end = TALLOC (nmatch, regoff_t);
5656 if (regs.start == NULL || regs.end == NULL)
5657 return (int) REG_NOMATCH;
5660 /* Perform the searching operation. */
5661 ret = re_search (&private_preg, string, len,
5662 /* start: */ 0, /* range: */ len,
5663 want_reg_info ? ®s : (struct re_registers *) 0);
5665 /* Copy the register information to the POSIX structure. */
5672 for (r = 0; r < nmatch; r++)
5674 pmatch[r].rm_so = regs.start[r];
5675 pmatch[r].rm_eo = regs.end[r];
5679 /* If we needed the temporary register info, free the space now. */
5684 /* We want zero return to mean success, unlike `re_search'. */
5685 return ret >= 0 ? (int) REG_NOERROR : (int) REG_NOMATCH;
5688 weak_alias (__regexec, regexec)
5692 /* Returns a message corresponding to an error code, ERRCODE, returned
5693 from either regcomp or regexec. We don't use PREG here. */
5696 regerror (errcode, preg, errbuf, errbuf_size)
5698 const regex_t *preg;
5707 || errcode >= (int) (sizeof (re_error_msgid)
5708 / sizeof (re_error_msgid[0])))
5709 /* Only error codes returned by the rest of the code should be passed
5710 to this routine. If we are given anything else, or if other regex
5711 code generates an invalid error code, then the program has a bug.
5712 Dump core so we can fix it. */
5715 msg = gettext (re_error_msgid[errcode]);
5717 msg_size = strlen (msg) + 1; /* Includes the null. */
5719 if (errbuf_size != 0)
5721 if (msg_size > errbuf_size)
5723 #if defined HAVE_MEMPCPY || defined _LIBC
5724 *((char *) __mempcpy (errbuf, msg, errbuf_size - 1)) = '\0';
5726 memcpy (errbuf, msg, errbuf_size - 1);
5727 errbuf[errbuf_size - 1] = 0;
5731 memcpy (errbuf, msg, msg_size);
5737 weak_alias (__regerror, regerror)
5741 /* Free dynamically allocated space used by PREG. */
5747 if (preg->buffer != NULL)
5748 free (preg->buffer);
5749 preg->buffer = NULL;
5751 preg->allocated = 0;
5754 if (preg->fastmap != NULL)
5755 free (preg->fastmap);
5756 preg->fastmap = NULL;
5757 preg->fastmap_accurate = 0;
5759 if (preg->translate != NULL)
5760 free (preg->translate);
5761 preg->translate = NULL;
5764 weak_alias (__regfree, regfree)
5767 #endif /* not emacs */
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