1 /* Extended regular expression matching and search library,
3 (Implements POSIX draft P10003.2/D11.2, except for
4 internationalization features.)
6 Copyright (C) 1993, 1994, 1995 Free Software Foundation, Inc.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
22 /* AIX requires this to be the first thing in the file. */
23 #if defined (_AIX) && !defined (REGEX_MALLOC)
33 /* We need this for `regex.h', and perhaps for the Emacs include files. */
34 #include <sys/types.h>
36 /* This is for other GNU distributions with internationalized messages. */
37 #if HAVE_LIBINTL_H || defined (_LIBC)
40 # define gettext(msgid) (msgid)
43 /* The `emacs' switch turns on certain matching commands
44 that make sense only in Emacs. */
53 /* If we are not linking with Emacs proper,
54 we can't use the relocating allocator
55 even if config.h says that we can. */
58 #if defined (STDC_HEADERS) || defined (_LIBC)
65 /* When used in Emacs's lib-src, we need to get bzero and bcopy somehow.
66 If nothing else has been done, use the method below. */
67 #ifdef INHIBIT_STRING_HEADER
68 #if !(defined (HAVE_BZERO) && defined (HAVE_BCOPY))
69 #if !defined (bzero) && !defined (bcopy)
70 #undef INHIBIT_STRING_HEADER
75 /* This is the normal way of making sure we have a bcopy and a bzero.
76 This is used in most programs--a few other programs avoid this
77 by defining INHIBIT_STRING_HEADER. */
78 #ifndef INHIBIT_STRING_HEADER
79 #if defined (HAVE_STRING_H) || defined (STDC_HEADERS) || defined (_LIBC)
82 #define bcmp(s1, s2, n) memcmp ((s1), (s2), (n))
85 #define bcopy(s, d, n) memcpy ((d), (s), (n))
88 #define bzero(s, n) memset ((s), 0, (n))
95 /* Define the syntax stuff for \<, \>, etc. */
97 /* This must be nonzero for the wordchar and notwordchar pattern
98 commands in re_match_2. */
103 #ifdef SWITCH_ENUM_BUG
104 #define SWITCH_ENUM_CAST(x) ((int)(x))
106 #define SWITCH_ENUM_CAST(x) (x)
111 extern char *re_syntax_table;
113 #else /* not SYNTAX_TABLE */
115 /* How many characters in the character set. */
116 #define CHAR_SET_SIZE 256
118 static char re_syntax_table[CHAR_SET_SIZE];
129 bzero (re_syntax_table, sizeof re_syntax_table);
131 for (c = 'a'; c <= 'z'; c++)
132 re_syntax_table[c] = Sword;
134 for (c = 'A'; c <= 'Z'; c++)
135 re_syntax_table[c] = Sword;
137 for (c = '0'; c <= '9'; c++)
138 re_syntax_table[c] = Sword;
140 re_syntax_table['_'] = Sword;
145 #endif /* not SYNTAX_TABLE */
147 #define SYNTAX(c) re_syntax_table[c]
149 #endif /* not emacs */
151 /* Get the interface, including the syntax bits. */
154 /* isalpha etc. are used for the character classes. */
157 /* Jim Meyering writes:
159 "... Some ctype macros are valid only for character codes that
160 isascii says are ASCII (SGI's IRIX-4.0.5 is one such system --when
161 using /bin/cc or gcc but without giving an ansi option). So, all
162 ctype uses should be through macros like ISPRINT... If
163 STDC_HEADERS is defined, then autoconf has verified that the ctype
164 macros don't need to be guarded with references to isascii. ...
165 Defining isascii to 1 should let any compiler worth its salt
166 eliminate the && through constant folding." */
168 #if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII))
171 #define ISASCII(c) isascii(c)
175 #define ISBLANK(c) (ISASCII (c) && isblank (c))
177 #define ISBLANK(c) ((c) == ' ' || (c) == '\t')
180 #define ISGRAPH(c) (ISASCII (c) && isgraph (c))
182 #define ISGRAPH(c) (ISASCII (c) && isprint (c) && !isspace (c))
185 #define ISPRINT(c) (ISASCII (c) && isprint (c))
186 #define ISDIGIT(c) (ISASCII (c) && isdigit (c))
187 #define ISALNUM(c) (ISASCII (c) && isalnum (c))
188 #define ISALPHA(c) (ISASCII (c) && isalpha (c))
189 #define ISCNTRL(c) (ISASCII (c) && iscntrl (c))
190 #define ISLOWER(c) (ISASCII (c) && islower (c))
191 #define ISPUNCT(c) (ISASCII (c) && ispunct (c))
192 #define ISSPACE(c) (ISASCII (c) && isspace (c))
193 #define ISUPPER(c) (ISASCII (c) && isupper (c))
194 #define ISXDIGIT(c) (ISASCII (c) && isxdigit (c))
197 #define NULL (void *)0
200 /* We remove any previous definition of `SIGN_EXTEND_CHAR',
201 since ours (we hope) works properly with all combinations of
202 machines, compilers, `char' and `unsigned char' argument types.
203 (Per Bothner suggested the basic approach.) */
204 #undef SIGN_EXTEND_CHAR
206 #define SIGN_EXTEND_CHAR(c) ((signed char) (c))
207 #else /* not __STDC__ */
208 /* As in Harbison and Steele. */
209 #define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128)
212 /* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we
213 use `alloca' instead of `malloc'. This is because using malloc in
214 re_search* or re_match* could cause memory leaks when C-g is used in
215 Emacs; also, malloc is slower and causes storage fragmentation. On
216 the other hand, malloc is more portable, and easier to debug.
218 Because we sometimes use alloca, some routines have to be macros,
219 not functions -- `alloca'-allocated space disappears at the end of the
220 function it is called in. */
224 #define REGEX_ALLOCATE malloc
225 #define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
226 #define REGEX_FREE free
228 #else /* not REGEX_MALLOC */
230 /* Emacs already defines alloca, sometimes. */
233 /* Make alloca work the best possible way. */
235 #define alloca __builtin_alloca
236 #else /* not __GNUC__ */
239 #else /* not __GNUC__ or HAVE_ALLOCA_H */
240 #ifndef _AIX /* Already did AIX, up at the top. */
241 #if defined (__STDC__) && __STDC__
246 #endif /* not _AIX */
247 #endif /* not HAVE_ALLOCA_H */
248 #endif /* not __GNUC__ */
250 #endif /* not alloca */
252 #define REGEX_ALLOCATE alloca
254 /* Assumes a `char *destination' variable. */
255 #define REGEX_REALLOCATE(source, osize, nsize) \
256 (destination = (char *) alloca (nsize), \
257 bcopy (source, destination, osize), \
260 /* No need to do anything to free, after alloca. */
261 #define REGEX_FREE(arg) ((void)0) /* Do nothing! But inhibit gcc warning. */
263 #endif /* not REGEX_MALLOC */
265 /* Define how to allocate the failure stack. */
267 #if defined (REL_ALLOC) && defined (REGEX_MALLOC)
269 #define REGEX_ALLOCATE_STACK(size) \
270 r_alloc (&failure_stack_ptr, (size))
271 #define REGEX_REALLOCATE_STACK(source, osize, nsize) \
272 r_re_alloc (&failure_stack_ptr, (nsize))
273 #define REGEX_FREE_STACK(ptr) \
274 r_alloc_free (&failure_stack_ptr)
276 #else /* not using relocating allocator */
280 #define REGEX_ALLOCATE_STACK malloc
281 #define REGEX_REALLOCATE_STACK(source, osize, nsize) realloc (source, nsize)
282 #define REGEX_FREE_STACK free
284 #else /* not REGEX_MALLOC */
286 #define REGEX_ALLOCATE_STACK alloca
288 #define REGEX_REALLOCATE_STACK(source, osize, nsize) \
289 REGEX_REALLOCATE (source, osize, nsize)
290 /* No need to explicitly free anything. */
291 #define REGEX_FREE_STACK(arg)
293 #endif /* not REGEX_MALLOC */
294 #endif /* not using relocating allocator */
297 /* True if `size1' is non-NULL and PTR is pointing anywhere inside
298 `string1' or just past its end. This works if PTR is NULL, which is
300 #define FIRST_STRING_P(ptr) \
301 (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
303 /* (Re)Allocate N items of type T using malloc, or fail. */
304 #define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
305 #define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
306 #define RETALLOC_IF(addr, n, t) \
307 if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
308 #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
310 #define BYTEWIDTH 8 /* In bits. */
312 #define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
316 #define MAX(a, b) ((a) > (b) ? (a) : (b))
317 #define MIN(a, b) ((a) < (b) ? (a) : (b))
319 typedef char boolean;
323 static int re_match_2_internal ();
325 /* These are the command codes that appear in compiled regular
326 expressions. Some opcodes are followed by argument bytes. A
327 command code can specify any interpretation whatsoever for its
328 arguments. Zero bytes may appear in the compiled regular expression. */
334 /* Succeed right away--no more backtracking. */
337 /* Followed by one byte giving n, then by n literal bytes. */
340 /* Matches any (more or less) character. */
343 /* Matches any one char belonging to specified set. First
344 following byte is number of bitmap bytes. Then come bytes
345 for a bitmap saying which chars are in. Bits in each byte
346 are ordered low-bit-first. A character is in the set if its
347 bit is 1. A character too large to have a bit in the map is
348 automatically not in the set. */
351 /* Same parameters as charset, but match any character that is
352 not one of those specified. */
355 /* Start remembering the text that is matched, for storing in a
356 register. Followed by one byte with the register number, in
357 the range 0 to one less than the pattern buffer's re_nsub
358 field. Then followed by one byte with the number of groups
359 inner to this one. (This last has to be part of the
360 start_memory only because we need it in the on_failure_jump
364 /* Stop remembering the text that is matched and store it in a
365 memory register. Followed by one byte with the register
366 number, in the range 0 to one less than `re_nsub' in the
367 pattern buffer, and one byte with the number of inner groups,
368 just like `start_memory'. (We need the number of inner
369 groups here because we don't have any easy way of finding the
370 corresponding start_memory when we're at a stop_memory.) */
373 /* Match a duplicate of something remembered. Followed by one
374 byte containing the register number. */
377 /* Fail unless at beginning of line. */
380 /* Fail unless at end of line. */
383 /* Succeeds if at beginning of buffer (if emacs) or at beginning
384 of string to be matched (if not). */
387 /* Analogously, for end of buffer/string. */
390 /* Followed by two byte relative address to which to jump. */
393 /* Same as jump, but marks the end of an alternative. */
396 /* Followed by two-byte relative address of place to resume at
397 in case of failure. */
400 /* Like on_failure_jump, but pushes a placeholder instead of the
401 current string position when executed. */
402 on_failure_keep_string_jump,
404 /* Throw away latest failure point and then jump to following
405 two-byte relative address. */
408 /* Change to pop_failure_jump if know won't have to backtrack to
409 match; otherwise change to jump. This is used to jump
410 back to the beginning of a repeat. If what follows this jump
411 clearly won't match what the repeat does, such that we can be
412 sure that there is no use backtracking out of repetitions
413 already matched, then we change it to a pop_failure_jump.
414 Followed by two-byte address. */
417 /* Jump to following two-byte address, and push a dummy failure
418 point. This failure point will be thrown away if an attempt
419 is made to use it for a failure. A `+' construct makes this
420 before the first repeat. Also used as an intermediary kind
421 of jump when compiling an alternative. */
424 /* Push a dummy failure point and continue. Used at the end of
428 /* Followed by two-byte relative address and two-byte number n.
429 After matching N times, jump to the address upon failure. */
432 /* Followed by two-byte relative address, and two-byte number n.
433 Jump to the address N times, then fail. */
436 /* Set the following two-byte relative address to the
437 subsequent two-byte number. The address *includes* the two
441 wordchar, /* Matches any word-constituent character. */
442 notwordchar, /* Matches any char that is not a word-constituent. */
444 wordbeg, /* Succeeds if at word beginning. */
445 wordend, /* Succeeds if at word end. */
447 wordbound, /* Succeeds if at a word boundary. */
448 notwordbound /* Succeeds if not at a word boundary. */
451 ,before_dot, /* Succeeds if before point. */
452 at_dot, /* Succeeds if at point. */
453 after_dot, /* Succeeds if after point. */
455 /* Matches any character whose syntax is specified. Followed by
456 a byte which contains a syntax code, e.g., Sword. */
459 /* Matches any character whose syntax is not that specified. */
464 /* Common operations on the compiled pattern. */
466 /* Store NUMBER in two contiguous bytes starting at DESTINATION. */
468 #define STORE_NUMBER(destination, number) \
470 (destination)[0] = (number) & 0377; \
471 (destination)[1] = (number) >> 8; \
474 /* Same as STORE_NUMBER, except increment DESTINATION to
475 the byte after where the number is stored. Therefore, DESTINATION
476 must be an lvalue. */
478 #define STORE_NUMBER_AND_INCR(destination, number) \
480 STORE_NUMBER (destination, number); \
481 (destination) += 2; \
484 /* Put into DESTINATION a number stored in two contiguous bytes starting
487 #define EXTRACT_NUMBER(destination, source) \
489 (destination) = *(source) & 0377; \
490 (destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8; \
495 extract_number (dest, source)
497 unsigned char *source;
499 int temp = SIGN_EXTEND_CHAR (*(source + 1));
500 *dest = *source & 0377;
504 #ifndef EXTRACT_MACROS /* To debug the macros. */
505 #undef EXTRACT_NUMBER
506 #define EXTRACT_NUMBER(dest, src) extract_number (&dest, src)
507 #endif /* not EXTRACT_MACROS */
511 /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
512 SOURCE must be an lvalue. */
514 #define EXTRACT_NUMBER_AND_INCR(destination, source) \
516 EXTRACT_NUMBER (destination, 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;
605 unsigned char *p = start;
606 unsigned char *pend = end;
614 /* Loop over pattern commands. */
617 printf ("%d:\t", p - start);
619 switch ((re_opcode_t) *p++)
627 printf ("/exactn/%d", mcnt);
638 printf ("/start_memory/%d/%d", mcnt, *p++);
643 printf ("/stop_memory/%d/%d", mcnt, *p++);
647 printf ("/duplicate/%d", *p++);
657 register int c, last = -100;
658 register int in_range = 0;
660 printf ("/charset [%s",
661 (re_opcode_t) *(p - 1) == charset_not ? "^" : "");
663 assert (p + *p < pend);
665 for (c = 0; c < 256; c++)
667 && (p[1 + (c/8)] & (1 << (c % 8))))
669 /* Are we starting a range? */
670 if (last + 1 == c && ! in_range)
675 /* Have we broken a range? */
676 else if (last + 1 != c && in_range)
705 case on_failure_jump:
706 extract_number_and_incr (&mcnt, &p);
707 printf ("/on_failure_jump to %d", p + mcnt - start);
710 case on_failure_keep_string_jump:
711 extract_number_and_incr (&mcnt, &p);
712 printf ("/on_failure_keep_string_jump to %d", p + mcnt - start);
715 case dummy_failure_jump:
716 extract_number_and_incr (&mcnt, &p);
717 printf ("/dummy_failure_jump to %d", p + mcnt - start);
720 case push_dummy_failure:
721 printf ("/push_dummy_failure");
725 extract_number_and_incr (&mcnt, &p);
726 printf ("/maybe_pop_jump to %d", p + mcnt - start);
729 case pop_failure_jump:
730 extract_number_and_incr (&mcnt, &p);
731 printf ("/pop_failure_jump to %d", p + mcnt - start);
735 extract_number_and_incr (&mcnt, &p);
736 printf ("/jump_past_alt to %d", p + mcnt - start);
740 extract_number_and_incr (&mcnt, &p);
741 printf ("/jump to %d", p + mcnt - start);
745 extract_number_and_incr (&mcnt, &p);
746 extract_number_and_incr (&mcnt2, &p);
747 printf ("/succeed_n to %d, %d times", p + mcnt - start, mcnt2);
751 extract_number_and_incr (&mcnt, &p);
752 extract_number_and_incr (&mcnt2, &p);
753 printf ("/jump_n to %d, %d times", p + mcnt - start, mcnt2);
757 extract_number_and_incr (&mcnt, &p);
758 extract_number_and_incr (&mcnt2, &p);
759 printf ("/set_number_at location %d to %d", p + mcnt - start, mcnt2);
763 printf ("/wordbound");
767 printf ("/notwordbound");
779 printf ("/before_dot");
787 printf ("/after_dot");
791 printf ("/syntaxspec");
793 printf ("/%d", mcnt);
797 printf ("/notsyntaxspec");
799 printf ("/%d", mcnt);
804 printf ("/wordchar");
808 printf ("/notwordchar");
820 printf ("?%d", *(p-1));
826 printf ("%d:\tend of pattern.\n", p - start);
831 print_compiled_pattern (bufp)
832 struct re_pattern_buffer *bufp;
834 unsigned char *buffer = bufp->buffer;
836 print_partial_compiled_pattern (buffer, buffer + bufp->used);
837 printf ("%d bytes used/%d bytes allocated.\n", bufp->used, bufp->allocated);
839 if (bufp->fastmap_accurate && bufp->fastmap)
841 printf ("fastmap: ");
842 print_fastmap (bufp->fastmap);
845 printf ("re_nsub: %d\t", bufp->re_nsub);
846 printf ("regs_alloc: %d\t", bufp->regs_allocated);
847 printf ("can_be_null: %d\t", bufp->can_be_null);
848 printf ("newline_anchor: %d\n", bufp->newline_anchor);
849 printf ("no_sub: %d\t", bufp->no_sub);
850 printf ("not_bol: %d\t", bufp->not_bol);
851 printf ("not_eol: %d\t", bufp->not_eol);
852 printf ("syntax: %d\n", bufp->syntax);
853 /* Perhaps we should print the translate table? */
858 print_double_string (where, string1, size1, string2, size2)
871 if (FIRST_STRING_P (where))
873 for (this_char = where - string1; this_char < size1; this_char++)
874 putchar (string1[this_char]);
879 for (this_char = where - string2; this_char < size2; this_char++)
880 putchar (string2[this_char]);
884 #else /* not DEBUG */
889 #define DEBUG_STATEMENT(e)
890 #define DEBUG_PRINT1(x)
891 #define DEBUG_PRINT2(x1, x2)
892 #define DEBUG_PRINT3(x1, x2, x3)
893 #define DEBUG_PRINT4(x1, x2, x3, x4)
894 #define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
895 #define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
897 #endif /* not DEBUG */
899 /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
900 also be assigned to arbitrarily: each pattern buffer stores its own
901 syntax, so it can be changed between regex compilations. */
902 /* This has no initializer because initialized variables in Emacs
903 become read-only after dumping. */
904 reg_syntax_t re_syntax_options;
907 /* Specify the precise syntax of regexps for compilation. This provides
908 for compatibility for various utilities which historically have
909 different, incompatible syntaxes.
911 The argument SYNTAX is a bit mask comprised of the various bits
912 defined in regex.h. We return the old syntax. */
915 re_set_syntax (syntax)
918 reg_syntax_t ret = re_syntax_options;
920 re_syntax_options = syntax;
924 /* This table gives an error message for each of the error codes listed
925 in regex.h. Obviously the order here has to be same as there.
926 POSIX doesn't require that we do anything for REG_NOERROR,
927 but why not be nice? */
929 static const char *re_error_msgid[] =
930 { "Success", /* REG_NOERROR */
931 "No match", /* REG_NOMATCH */
932 "Invalid regular expression", /* REG_BADPAT */
933 "Invalid collation character", /* REG_ECOLLATE */
934 "Invalid character class name", /* REG_ECTYPE */
935 "Trailing backslash", /* REG_EESCAPE */
936 "Invalid back reference", /* REG_ESUBREG */
937 "Unmatched [ or [^", /* REG_EBRACK */
938 "Unmatched ( or \\(", /* REG_EPAREN */
939 "Unmatched \\{", /* REG_EBRACE */
940 "Invalid content of \\{\\}", /* REG_BADBR */
941 "Invalid range end", /* REG_ERANGE */
942 "Memory exhausted", /* REG_ESPACE */
943 "Invalid preceding regular expression", /* REG_BADRPT */
944 "Premature end of regular expression", /* REG_EEND */
945 "Regular expression too big", /* REG_ESIZE */
946 "Unmatched ) or \\)", /* REG_ERPAREN */
949 /* Avoiding alloca during matching, to placate r_alloc. */
951 /* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
952 searching and matching functions should not call alloca. On some
953 systems, alloca is implemented in terms of malloc, and if we're
954 using the relocating allocator routines, then malloc could cause a
955 relocation, which might (if the strings being searched are in the
956 ralloc heap) shift the data out from underneath the regexp
959 Here's another reason to avoid allocation: Emacs
960 processes input from X in a signal handler; processing X input may
961 call malloc; if input arrives while a matching routine is calling
962 malloc, then we're scrod. But Emacs can't just block input while
963 calling matching routines; then we don't notice interrupts when
964 they come in. So, Emacs blocks input around all regexp calls
965 except the matching calls, which it leaves unprotected, in the
966 faith that they will not malloc. */
968 /* Normally, this is fine. */
969 #define MATCH_MAY_ALLOCATE
971 /* When using GNU C, we are not REALLY using the C alloca, no matter
972 what config.h may say. So don't take precautions for it. */
977 /* The match routines may not allocate if (1) they would do it with malloc
978 and (2) it's not safe for them to use malloc.
979 Note that if REL_ALLOC is defined, matching would not use malloc for the
980 failure stack, but we would still use it for the register vectors;
981 so REL_ALLOC should not affect this. */
982 #if (defined (C_ALLOCA) || defined (REGEX_MALLOC)) && defined (emacs)
983 #undef MATCH_MAY_ALLOCATE
987 /* Failure stack declarations and macros; both re_compile_fastmap and
988 re_match_2 use a failure stack. These have to be macros because of
989 REGEX_ALLOCATE_STACK. */
992 /* Number of failure points for which to initially allocate space
993 when matching. If this number is exceeded, we allocate more
994 space, so it is not a hard limit. */
995 #ifndef INIT_FAILURE_ALLOC
996 #define INIT_FAILURE_ALLOC 5
999 /* Roughly the maximum number of failure points on the stack. Would be
1000 exactly that if always used MAX_FAILURE_SPACE each time we failed.
1001 This is a variable only so users of regex can assign to it; we never
1002 change it ourselves. */
1003 #if defined (MATCH_MAY_ALLOCATE)
1004 int re_max_failures = 200000;
1006 int re_max_failures = 2000;
1009 union fail_stack_elt
1011 unsigned char *pointer;
1015 typedef union fail_stack_elt fail_stack_elt_t;
1019 fail_stack_elt_t *stack;
1021 unsigned avail; /* Offset of next open position. */
1024 #define FAIL_STACK_EMPTY() (fail_stack.avail == 0)
1025 #define FAIL_STACK_PTR_EMPTY() (fail_stack_ptr->avail == 0)
1026 #define FAIL_STACK_FULL() (fail_stack.avail == fail_stack.size)
1029 /* Define macros to initialize and free the failure stack.
1030 Do `return -2' if the alloc fails. */
1032 #ifdef MATCH_MAY_ALLOCATE
1033 #define INIT_FAIL_STACK() \
1035 fail_stack.stack = (fail_stack_elt_t *) \
1036 REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * sizeof (fail_stack_elt_t)); \
1038 if (fail_stack.stack == NULL) \
1041 fail_stack.size = INIT_FAILURE_ALLOC; \
1042 fail_stack.avail = 0; \
1045 #define RESET_FAIL_STACK() REGEX_FREE_STACK (fail_stack.stack)
1047 #define INIT_FAIL_STACK() \
1049 fail_stack.avail = 0; \
1052 #define RESET_FAIL_STACK()
1056 /* Double the size of FAIL_STACK, up to approximately `re_max_failures' items.
1058 Return 1 if succeeds, and 0 if either ran out of memory
1059 allocating space for it or it was already too large.
1061 REGEX_REALLOCATE_STACK requires `destination' be declared. */
1063 #define DOUBLE_FAIL_STACK(fail_stack) \
1064 ((fail_stack).size > re_max_failures * MAX_FAILURE_ITEMS \
1066 : ((fail_stack).stack = (fail_stack_elt_t *) \
1067 REGEX_REALLOCATE_STACK ((fail_stack).stack, \
1068 (fail_stack).size * sizeof (fail_stack_elt_t), \
1069 ((fail_stack).size << 1) * sizeof (fail_stack_elt_t)), \
1071 (fail_stack).stack == NULL \
1073 : ((fail_stack).size <<= 1, \
1077 /* Push pointer POINTER on FAIL_STACK.
1078 Return 1 if was able to do so and 0 if ran out of memory allocating
1080 #define PUSH_PATTERN_OP(POINTER, FAIL_STACK) \
1081 ((FAIL_STACK_FULL () \
1082 && !DOUBLE_FAIL_STACK (FAIL_STACK)) \
1084 : ((FAIL_STACK).stack[(FAIL_STACK).avail++].pointer = POINTER, \
1087 /* Push a pointer value onto the failure stack.
1088 Assumes the variable `fail_stack'. Probably should only
1089 be called from within `PUSH_FAILURE_POINT'. */
1090 #define PUSH_FAILURE_POINTER(item) \
1091 fail_stack.stack[fail_stack.avail++].pointer = (unsigned char *) (item)
1093 /* This pushes an integer-valued item onto the failure stack.
1094 Assumes the variable `fail_stack'. Probably should only
1095 be called from within `PUSH_FAILURE_POINT'. */
1096 #define PUSH_FAILURE_INT(item) \
1097 fail_stack.stack[fail_stack.avail++].integer = (item)
1099 /* Push a fail_stack_elt_t value onto the failure stack.
1100 Assumes the variable `fail_stack'. Probably should only
1101 be called from within `PUSH_FAILURE_POINT'. */
1102 #define PUSH_FAILURE_ELT(item) \
1103 fail_stack.stack[fail_stack.avail++] = (item)
1105 /* These three POP... operations complement the three PUSH... operations.
1106 All assume that `fail_stack' is nonempty. */
1107 #define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
1108 #define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
1109 #define POP_FAILURE_ELT() fail_stack.stack[--fail_stack.avail]
1111 /* Used to omit pushing failure point id's when we're not debugging. */
1113 #define DEBUG_PUSH PUSH_FAILURE_INT
1114 #define DEBUG_POP(item_addr) *(item_addr) = POP_FAILURE_INT ()
1116 #define DEBUG_PUSH(item)
1117 #define DEBUG_POP(item_addr)
1121 /* Push the information about the state we will need
1122 if we ever fail back to it.
1124 Requires variables fail_stack, regstart, regend, reg_info, and
1125 num_regs be declared. DOUBLE_FAIL_STACK requires `destination' be
1128 Does `return FAILURE_CODE' if runs out of memory. */
1130 #define PUSH_FAILURE_POINT(pattern_place, string_place, failure_code) \
1132 char *destination; \
1133 /* Must be int, so when we don't save any registers, the arithmetic \
1134 of 0 + -1 isn't done as unsigned. */ \
1137 DEBUG_STATEMENT (failure_id++); \
1138 DEBUG_STATEMENT (nfailure_points_pushed++); \
1139 DEBUG_PRINT2 ("\nPUSH_FAILURE_POINT #%u:\n", failure_id); \
1140 DEBUG_PRINT2 (" Before push, next avail: %d\n", (fail_stack).avail);\
1141 DEBUG_PRINT2 (" size: %d\n", (fail_stack).size);\
1143 DEBUG_PRINT2 (" slots needed: %d\n", NUM_FAILURE_ITEMS); \
1144 DEBUG_PRINT2 (" available: %d\n", REMAINING_AVAIL_SLOTS); \
1146 /* Ensure we have enough space allocated for what we will push. */ \
1147 while (REMAINING_AVAIL_SLOTS < NUM_FAILURE_ITEMS) \
1149 if (!DOUBLE_FAIL_STACK (fail_stack)) \
1150 return failure_code; \
1152 DEBUG_PRINT2 ("\n Doubled stack; size now: %d\n", \
1153 (fail_stack).size); \
1154 DEBUG_PRINT2 (" slots available: %d\n", REMAINING_AVAIL_SLOTS);\
1157 /* Push the info, starting with the registers. */ \
1158 DEBUG_PRINT1 ("\n"); \
1160 if (!(RE_NO_POSIX_BACKTRACKING & bufp->syntax)) \
1161 for (this_reg = lowest_active_reg; this_reg <= highest_active_reg; \
1164 DEBUG_PRINT2 (" Pushing reg: %d\n", this_reg); \
1165 DEBUG_STATEMENT (num_regs_pushed++); \
1167 DEBUG_PRINT2 (" start: 0x%x\n", regstart[this_reg]); \
1168 PUSH_FAILURE_POINTER (regstart[this_reg]); \
1170 DEBUG_PRINT2 (" end: 0x%x\n", regend[this_reg]); \
1171 PUSH_FAILURE_POINTER (regend[this_reg]); \
1173 DEBUG_PRINT2 (" info: 0x%x\n ", reg_info[this_reg]); \
1174 DEBUG_PRINT2 (" match_null=%d", \
1175 REG_MATCH_NULL_STRING_P (reg_info[this_reg])); \
1176 DEBUG_PRINT2 (" active=%d", IS_ACTIVE (reg_info[this_reg])); \
1177 DEBUG_PRINT2 (" matched_something=%d", \
1178 MATCHED_SOMETHING (reg_info[this_reg])); \
1179 DEBUG_PRINT2 (" ever_matched=%d", \
1180 EVER_MATCHED_SOMETHING (reg_info[this_reg])); \
1181 DEBUG_PRINT1 ("\n"); \
1182 PUSH_FAILURE_ELT (reg_info[this_reg].word); \
1185 DEBUG_PRINT2 (" Pushing low active reg: %d\n", lowest_active_reg);\
1186 PUSH_FAILURE_INT (lowest_active_reg); \
1188 DEBUG_PRINT2 (" Pushing high active reg: %d\n", highest_active_reg);\
1189 PUSH_FAILURE_INT (highest_active_reg); \
1191 DEBUG_PRINT2 (" Pushing pattern 0x%x: ", pattern_place); \
1192 DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern_place, pend); \
1193 PUSH_FAILURE_POINTER (pattern_place); \
1195 DEBUG_PRINT2 (" Pushing string 0x%x: `", string_place); \
1196 DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2, \
1198 DEBUG_PRINT1 ("'\n"); \
1199 PUSH_FAILURE_POINTER (string_place); \
1201 DEBUG_PRINT2 (" Pushing failure id: %u\n", failure_id); \
1202 DEBUG_PUSH (failure_id); \
1205 /* This is the number of items that are pushed and popped on the stack
1206 for each register. */
1207 #define NUM_REG_ITEMS 3
1209 /* Individual items aside from the registers. */
1211 #define NUM_NONREG_ITEMS 5 /* Includes failure point id. */
1213 #define NUM_NONREG_ITEMS 4
1216 /* We push at most this many items on the stack. */
1217 #define MAX_FAILURE_ITEMS ((num_regs - 1) * NUM_REG_ITEMS + NUM_NONREG_ITEMS)
1219 /* We actually push this many items. */
1220 #define NUM_FAILURE_ITEMS \
1221 (((RE_NO_POSIX_BACKTRACKING & bufp->syntax \
1222 ? 0 : highest_active_reg - lowest_active_reg + 1) \
1226 /* How many items can still be added to the stack without overflowing it. */
1227 #define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
1230 /* Pops what PUSH_FAIL_STACK pushes.
1232 We restore into the parameters, all of which should be lvalues:
1233 STR -- the saved data position.
1234 PAT -- the saved pattern position.
1235 LOW_REG, HIGH_REG -- the highest and lowest active registers.
1236 REGSTART, REGEND -- arrays of string positions.
1237 REG_INFO -- array of information about each subexpression.
1239 Also assumes the variables `fail_stack' and (if debugging), `bufp',
1240 `pend', `string1', `size1', `string2', and `size2'. */
1242 #define POP_FAILURE_POINT(str, pat, low_reg, high_reg, regstart, regend, reg_info)\
1244 DEBUG_STATEMENT (fail_stack_elt_t failure_id;) \
1246 const unsigned char *string_temp; \
1248 assert (!FAIL_STACK_EMPTY ()); \
1250 /* Remove failure points and point to how many regs pushed. */ \
1251 DEBUG_PRINT1 ("POP_FAILURE_POINT:\n"); \
1252 DEBUG_PRINT2 (" Before pop, next avail: %d\n", fail_stack.avail); \
1253 DEBUG_PRINT2 (" size: %d\n", fail_stack.size); \
1255 assert (fail_stack.avail >= NUM_NONREG_ITEMS); \
1257 DEBUG_POP (&failure_id); \
1258 DEBUG_PRINT2 (" Popping failure id: %u\n", failure_id); \
1260 /* If the saved string location is NULL, it came from an \
1261 on_failure_keep_string_jump opcode, and we want to throw away the \
1262 saved NULL, thus retaining our current position in the string. */ \
1263 string_temp = POP_FAILURE_POINTER (); \
1264 if (string_temp != NULL) \
1265 str = (const char *) string_temp; \
1267 DEBUG_PRINT2 (" Popping string 0x%x: `", str); \
1268 DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2); \
1269 DEBUG_PRINT1 ("'\n"); \
1271 pat = (unsigned char *) POP_FAILURE_POINTER (); \
1272 DEBUG_PRINT2 (" Popping pattern 0x%x: ", pat); \
1273 DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend); \
1275 /* Restore register info. */ \
1276 high_reg = (unsigned) POP_FAILURE_INT (); \
1277 DEBUG_PRINT2 (" Popping high active reg: %d\n", high_reg); \
1279 low_reg = (unsigned) POP_FAILURE_INT (); \
1280 DEBUG_PRINT2 (" Popping low active reg: %d\n", low_reg); \
1282 if (!(RE_NO_POSIX_BACKTRACKING & bufp->syntax)) \
1283 for (this_reg = high_reg; this_reg >= low_reg; this_reg--) \
1285 DEBUG_PRINT2 (" Popping reg: %d\n", this_reg); \
1287 reg_info[this_reg].word = POP_FAILURE_ELT (); \
1288 DEBUG_PRINT2 (" info: 0x%x\n", reg_info[this_reg]); \
1290 regend[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1291 DEBUG_PRINT2 (" end: 0x%x\n", regend[this_reg]); \
1293 regstart[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1294 DEBUG_PRINT2 (" start: 0x%x\n", regstart[this_reg]); \
1298 for (this_reg = highest_active_reg; this_reg > high_reg; this_reg--) \
1300 reg_info[this_reg].word = 0; \
1301 regend[this_reg] = 0; \
1302 regstart[this_reg] = 0; \
1304 highest_active_reg = high_reg; \
1307 set_regs_matched_done = 0; \
1308 DEBUG_STATEMENT (nfailure_points_popped++); \
1309 } /* POP_FAILURE_POINT */
1313 /* Structure for per-register (a.k.a. per-group) information.
1314 Other register information, such as the
1315 starting and ending positions (which are addresses), and the list of
1316 inner groups (which is a bits list) are maintained in separate
1319 We are making a (strictly speaking) nonportable assumption here: that
1320 the compiler will pack our bit fields into something that fits into
1321 the type of `word', i.e., is something that fits into one item on the
1326 fail_stack_elt_t word;
1329 /* This field is one if this group can match the empty string,
1330 zero if not. If not yet determined, `MATCH_NULL_UNSET_VALUE'. */
1331 #define MATCH_NULL_UNSET_VALUE 3
1332 unsigned match_null_string_p : 2;
1333 unsigned is_active : 1;
1334 unsigned matched_something : 1;
1335 unsigned ever_matched_something : 1;
1337 } register_info_type;
1339 #define REG_MATCH_NULL_STRING_P(R) ((R).bits.match_null_string_p)
1340 #define IS_ACTIVE(R) ((R).bits.is_active)
1341 #define MATCHED_SOMETHING(R) ((R).bits.matched_something)
1342 #define EVER_MATCHED_SOMETHING(R) ((R).bits.ever_matched_something)
1345 /* Call this when have matched a real character; it sets `matched' flags
1346 for the subexpressions which we are currently inside. Also records
1347 that those subexprs have matched. */
1348 #define SET_REGS_MATCHED() \
1351 if (!set_regs_matched_done) \
1354 set_regs_matched_done = 1; \
1355 for (r = lowest_active_reg; r <= highest_active_reg; r++) \
1357 MATCHED_SOMETHING (reg_info[r]) \
1358 = EVER_MATCHED_SOMETHING (reg_info[r]) \
1365 /* Registers are set to a sentinel when they haven't yet matched. */
1366 static char reg_unset_dummy;
1367 #define REG_UNSET_VALUE (®_unset_dummy)
1368 #define REG_UNSET(e) ((e) == REG_UNSET_VALUE)
1370 /* Subroutine declarations and macros for regex_compile. */
1372 static void store_op1 (), store_op2 ();
1373 static void insert_op1 (), insert_op2 ();
1374 static boolean at_begline_loc_p (), at_endline_loc_p ();
1375 static boolean group_in_compile_stack ();
1376 static reg_errcode_t compile_range ();
1378 /* Fetch the next character in the uncompiled pattern---translating it
1379 if necessary. Also cast from a signed character in the constant
1380 string passed to us by the user to an unsigned char that we can use
1381 as an array index (in, e.g., `translate'). */
1383 #define PATFETCH(c) \
1384 do {if (p == pend) return REG_EEND; \
1385 c = (unsigned char) *p++; \
1386 if (translate) c = (unsigned char) translate[c]; \
1390 /* Fetch the next character in the uncompiled pattern, with no
1392 #define PATFETCH_RAW(c) \
1393 do {if (p == pend) return REG_EEND; \
1394 c = (unsigned char) *p++; \
1397 /* Go backwards one character in the pattern. */
1398 #define PATUNFETCH p--
1401 /* If `translate' is non-null, return translate[D], else just D. We
1402 cast the subscript to translate because some data is declared as
1403 `char *', to avoid warnings when a string constant is passed. But
1404 when we use a character as a subscript we must make it unsigned. */
1406 #define TRANSLATE(d) \
1407 (translate ? (char) translate[(unsigned char) (d)] : (d))
1411 /* Macros for outputting the compiled pattern into `buffer'. */
1413 /* If the buffer isn't allocated when it comes in, use this. */
1414 #define INIT_BUF_SIZE 32
1416 /* Make sure we have at least N more bytes of space in buffer. */
1417 #define GET_BUFFER_SPACE(n) \
1418 while (b - bufp->buffer + (n) > bufp->allocated) \
1421 /* Make sure we have one more byte of buffer space and then add C to it. */
1422 #define BUF_PUSH(c) \
1424 GET_BUFFER_SPACE (1); \
1425 *b++ = (unsigned char) (c); \
1429 /* Ensure we have two more bytes of buffer space and then append C1 and C2. */
1430 #define BUF_PUSH_2(c1, c2) \
1432 GET_BUFFER_SPACE (2); \
1433 *b++ = (unsigned char) (c1); \
1434 *b++ = (unsigned char) (c2); \
1438 /* As with BUF_PUSH_2, except for three bytes. */
1439 #define BUF_PUSH_3(c1, c2, c3) \
1441 GET_BUFFER_SPACE (3); \
1442 *b++ = (unsigned char) (c1); \
1443 *b++ = (unsigned char) (c2); \
1444 *b++ = (unsigned char) (c3); \
1448 /* Store a jump with opcode OP at LOC to location TO. We store a
1449 relative address offset by the three bytes the jump itself occupies. */
1450 #define STORE_JUMP(op, loc, to) \
1451 store_op1 (op, loc, (to) - (loc) - 3)
1453 /* Likewise, for a two-argument jump. */
1454 #define STORE_JUMP2(op, loc, to, arg) \
1455 store_op2 (op, loc, (to) - (loc) - 3, arg)
1457 /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
1458 #define INSERT_JUMP(op, loc, to) \
1459 insert_op1 (op, loc, (to) - (loc) - 3, b)
1461 /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
1462 #define INSERT_JUMP2(op, loc, to, arg) \
1463 insert_op2 (op, loc, (to) - (loc) - 3, arg, b)
1466 /* This is not an arbitrary limit: the arguments which represent offsets
1467 into the pattern are two bytes long. So if 2^16 bytes turns out to
1468 be too small, many things would have to change. */
1469 #define MAX_BUF_SIZE (1L << 16)
1472 /* Extend the buffer by twice its current size via realloc and
1473 reset the pointers that pointed into the old block to point to the
1474 correct places in the new one. If extending the buffer results in it
1475 being larger than MAX_BUF_SIZE, then flag memory exhausted. */
1476 #define EXTEND_BUFFER() \
1478 unsigned char *old_buffer = bufp->buffer; \
1479 if (bufp->allocated == MAX_BUF_SIZE) \
1481 bufp->allocated <<= 1; \
1482 if (bufp->allocated > MAX_BUF_SIZE) \
1483 bufp->allocated = MAX_BUF_SIZE; \
1484 bufp->buffer = (unsigned char *) realloc (bufp->buffer, bufp->allocated);\
1485 if (bufp->buffer == NULL) \
1486 return REG_ESPACE; \
1487 /* If the buffer moved, move all the pointers into it. */ \
1488 if (old_buffer != bufp->buffer) \
1490 b = (b - old_buffer) + bufp->buffer; \
1491 begalt = (begalt - old_buffer) + bufp->buffer; \
1492 if (fixup_alt_jump) \
1493 fixup_alt_jump = (fixup_alt_jump - old_buffer) + bufp->buffer;\
1495 laststart = (laststart - old_buffer) + bufp->buffer; \
1496 if (pending_exact) \
1497 pending_exact = (pending_exact - old_buffer) + bufp->buffer; \
1502 /* Since we have one byte reserved for the register number argument to
1503 {start,stop}_memory, the maximum number of groups we can report
1504 things about is what fits in that byte. */
1505 #define MAX_REGNUM 255
1507 /* But patterns can have more than `MAX_REGNUM' registers. We just
1508 ignore the excess. */
1509 typedef unsigned regnum_t;
1512 /* Macros for the compile stack. */
1514 /* Since offsets can go either forwards or backwards, this type needs to
1515 be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
1516 typedef int pattern_offset_t;
1520 pattern_offset_t begalt_offset;
1521 pattern_offset_t fixup_alt_jump;
1522 pattern_offset_t inner_group_offset;
1523 pattern_offset_t laststart_offset;
1525 } compile_stack_elt_t;
1530 compile_stack_elt_t *stack;
1532 unsigned avail; /* Offset of next open position. */
1533 } compile_stack_type;
1536 #define INIT_COMPILE_STACK_SIZE 32
1538 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
1539 #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
1541 /* The next available element. */
1542 #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
1545 /* Set the bit for character C in a list. */
1546 #define SET_LIST_BIT(c) \
1547 (b[((unsigned char) (c)) / BYTEWIDTH] \
1548 |= 1 << (((unsigned char) c) % BYTEWIDTH))
1551 /* Get the next unsigned number in the uncompiled pattern. */
1552 #define GET_UNSIGNED_NUMBER(num) \
1556 while (ISDIGIT (c)) \
1560 num = num * 10 + c - '0'; \
1568 #define CHAR_CLASS_MAX_LENGTH 6 /* Namely, `xdigit'. */
1570 #define IS_CHAR_CLASS(string) \
1571 (STREQ (string, "alpha") || STREQ (string, "upper") \
1572 || STREQ (string, "lower") || STREQ (string, "digit") \
1573 || STREQ (string, "alnum") || STREQ (string, "xdigit") \
1574 || STREQ (string, "space") || STREQ (string, "print") \
1575 || STREQ (string, "punct") || STREQ (string, "graph") \
1576 || STREQ (string, "cntrl") || STREQ (string, "blank"))
1578 #ifndef MATCH_MAY_ALLOCATE
1580 /* If we cannot allocate large objects within re_match_2_internal,
1581 we make the fail stack and register vectors global.
1582 The fail stack, we grow to the maximum size when a regexp
1584 The register vectors, we adjust in size each time we
1585 compile a regexp, according to the number of registers it needs. */
1587 static fail_stack_type fail_stack;
1589 /* Size with which the following vectors are currently allocated.
1590 That is so we can make them bigger as needed,
1591 but never make them smaller. */
1592 static int regs_allocated_size;
1594 static const char ** regstart, ** regend;
1595 static const char ** old_regstart, ** old_regend;
1596 static const char **best_regstart, **best_regend;
1597 static register_info_type *reg_info;
1598 static const char **reg_dummy;
1599 static register_info_type *reg_info_dummy;
1601 /* Make the register vectors big enough for NUM_REGS registers,
1602 but don't make them smaller. */
1605 regex_grow_registers (num_regs)
1608 if (num_regs > regs_allocated_size)
1610 RETALLOC_IF (regstart, num_regs, const char *);
1611 RETALLOC_IF (regend, num_regs, const char *);
1612 RETALLOC_IF (old_regstart, num_regs, const char *);
1613 RETALLOC_IF (old_regend, num_regs, const char *);
1614 RETALLOC_IF (best_regstart, num_regs, const char *);
1615 RETALLOC_IF (best_regend, num_regs, const char *);
1616 RETALLOC_IF (reg_info, num_regs, register_info_type);
1617 RETALLOC_IF (reg_dummy, num_regs, const char *);
1618 RETALLOC_IF (reg_info_dummy, num_regs, register_info_type);
1620 regs_allocated_size = num_regs;
1624 #endif /* not MATCH_MAY_ALLOCATE */
1626 /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
1627 Returns one of error codes defined in `regex.h', or zero for success.
1629 Assumes the `allocated' (and perhaps `buffer') and `translate'
1630 fields are set in BUFP on entry.
1632 If it succeeds, results are put in BUFP (if it returns an error, the
1633 contents of BUFP are undefined):
1634 `buffer' is the compiled pattern;
1635 `syntax' is set to SYNTAX;
1636 `used' is set to the length of the compiled pattern;
1637 `fastmap_accurate' is zero;
1638 `re_nsub' is the number of subexpressions in PATTERN;
1639 `not_bol' and `not_eol' are zero;
1641 The `fastmap' and `newline_anchor' fields are neither
1642 examined nor set. */
1644 /* Return, freeing storage we allocated. */
1645 #define FREE_STACK_RETURN(value) \
1646 return (free (compile_stack.stack), value)
1648 static reg_errcode_t
1649 regex_compile (pattern, size, syntax, bufp)
1650 const char *pattern;
1652 reg_syntax_t syntax;
1653 struct re_pattern_buffer *bufp;
1655 /* We fetch characters from PATTERN here. Even though PATTERN is
1656 `char *' (i.e., signed), we declare these variables as unsigned, so
1657 they can be reliably used as array indices. */
1658 register unsigned char c, c1;
1660 /* A random temporary spot in PATTERN. */
1663 /* Points to the end of the buffer, where we should append. */
1664 register unsigned char *b;
1666 /* Keeps track of unclosed groups. */
1667 compile_stack_type compile_stack;
1669 /* Points to the current (ending) position in the pattern. */
1670 const char *p = pattern;
1671 const char *pend = pattern + size;
1673 /* How to translate the characters in the pattern. */
1674 RE_TRANSLATE_TYPE translate = bufp->translate;
1676 /* Address of the count-byte of the most recently inserted `exactn'
1677 command. This makes it possible to tell if a new exact-match
1678 character can be added to that command or if the character requires
1679 a new `exactn' command. */
1680 unsigned char *pending_exact = 0;
1682 /* Address of start of the most recently finished expression.
1683 This tells, e.g., postfix * where to find the start of its
1684 operand. Reset at the beginning of groups and alternatives. */
1685 unsigned char *laststart = 0;
1687 /* Address of beginning of regexp, or inside of last group. */
1688 unsigned char *begalt;
1690 /* Place in the uncompiled pattern (i.e., the {) to
1691 which to go back if the interval is invalid. */
1692 const char *beg_interval;
1694 /* Address of the place where a forward jump should go to the end of
1695 the containing expression. Each alternative of an `or' -- except the
1696 last -- ends with a forward jump of this sort. */
1697 unsigned char *fixup_alt_jump = 0;
1699 /* Counts open-groups as they are encountered. Remembered for the
1700 matching close-group on the compile stack, so the same register
1701 number is put in the stop_memory as the start_memory. */
1702 regnum_t regnum = 0;
1705 DEBUG_PRINT1 ("\nCompiling pattern: ");
1708 unsigned debug_count;
1710 for (debug_count = 0; debug_count < size; debug_count++)
1711 putchar (pattern[debug_count]);
1716 /* Initialize the compile stack. */
1717 compile_stack.stack = TALLOC (INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
1718 if (compile_stack.stack == NULL)
1721 compile_stack.size = INIT_COMPILE_STACK_SIZE;
1722 compile_stack.avail = 0;
1724 /* Initialize the pattern buffer. */
1725 bufp->syntax = syntax;
1726 bufp->fastmap_accurate = 0;
1727 bufp->not_bol = bufp->not_eol = 0;
1729 /* Set `used' to zero, so that if we return an error, the pattern
1730 printer (for debugging) will think there's no pattern. We reset it
1734 /* Always count groups, whether or not bufp->no_sub is set. */
1737 #if !defined (emacs) && !defined (SYNTAX_TABLE)
1738 /* Initialize the syntax table. */
1739 init_syntax_once ();
1742 if (bufp->allocated == 0)
1745 { /* If zero allocated, but buffer is non-null, try to realloc
1746 enough space. This loses if buffer's address is bogus, but
1747 that is the user's responsibility. */
1748 RETALLOC (bufp->buffer, INIT_BUF_SIZE, unsigned char);
1751 { /* Caller did not allocate a buffer. Do it for them. */
1752 bufp->buffer = TALLOC (INIT_BUF_SIZE, unsigned char);
1754 if (!bufp->buffer) FREE_STACK_RETURN (REG_ESPACE);
1756 bufp->allocated = INIT_BUF_SIZE;
1759 begalt = b = bufp->buffer;
1761 /* Loop through the uncompiled pattern until we're at the end. */
1770 if ( /* If at start of pattern, it's an operator. */
1772 /* If context independent, it's an operator. */
1773 || syntax & RE_CONTEXT_INDEP_ANCHORS
1774 /* Otherwise, depends on what's come before. */
1775 || at_begline_loc_p (pattern, p, syntax))
1785 if ( /* If at end of pattern, it's an operator. */
1787 /* If context independent, it's an operator. */
1788 || syntax & RE_CONTEXT_INDEP_ANCHORS
1789 /* Otherwise, depends on what's next. */
1790 || at_endline_loc_p (p, pend, syntax))
1800 if ((syntax & RE_BK_PLUS_QM)
1801 || (syntax & RE_LIMITED_OPS))
1805 /* If there is no previous pattern... */
1808 if (syntax & RE_CONTEXT_INVALID_OPS)
1809 FREE_STACK_RETURN (REG_BADRPT);
1810 else if (!(syntax & RE_CONTEXT_INDEP_OPS))
1815 /* Are we optimizing this jump? */
1816 boolean keep_string_p = false;
1818 /* 1 means zero (many) matches is allowed. */
1819 char zero_times_ok = 0, many_times_ok = 0;
1821 /* If there is a sequence of repetition chars, collapse it
1822 down to just one (the right one). We can't combine
1823 interval operators with these because of, e.g., `a{2}*',
1824 which should only match an even number of `a's. */
1828 zero_times_ok |= c != '+';
1829 many_times_ok |= c != '?';
1837 || (!(syntax & RE_BK_PLUS_QM) && (c == '+' || c == '?')))
1840 else if (syntax & RE_BK_PLUS_QM && c == '\\')
1842 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
1845 if (!(c1 == '+' || c1 == '?'))
1860 /* If we get here, we found another repeat character. */
1863 /* Star, etc. applied to an empty pattern is equivalent
1864 to an empty pattern. */
1868 /* Now we know whether or not zero matches is allowed
1869 and also whether or not two or more matches is allowed. */
1871 { /* More than one repetition is allowed, so put in at the
1872 end a backward relative jump from `b' to before the next
1873 jump we're going to put in below (which jumps from
1874 laststart to after this jump).
1876 But if we are at the `*' in the exact sequence `.*\n',
1877 insert an unconditional jump backwards to the .,
1878 instead of the beginning of the loop. This way we only
1879 push a failure point once, instead of every time
1880 through the loop. */
1881 assert (p - 1 > pattern);
1883 /* Allocate the space for the jump. */
1884 GET_BUFFER_SPACE (3);
1886 /* We know we are not at the first character of the pattern,
1887 because laststart was nonzero. And we've already
1888 incremented `p', by the way, to be the character after
1889 the `*'. Do we have to do something analogous here
1890 for null bytes, because of RE_DOT_NOT_NULL? */
1891 if (TRANSLATE (*(p - 2)) == TRANSLATE ('.')
1893 && p < pend && TRANSLATE (*p) == TRANSLATE ('\n')
1894 && !(syntax & RE_DOT_NEWLINE))
1895 { /* We have .*\n. */
1896 STORE_JUMP (jump, b, laststart);
1897 keep_string_p = true;
1900 /* Anything else. */
1901 STORE_JUMP (maybe_pop_jump, b, laststart - 3);
1903 /* We've added more stuff to the buffer. */
1907 /* On failure, jump from laststart to b + 3, which will be the
1908 end of the buffer after this jump is inserted. */
1909 GET_BUFFER_SPACE (3);
1910 INSERT_JUMP (keep_string_p ? on_failure_keep_string_jump
1918 /* At least one repetition is required, so insert a
1919 `dummy_failure_jump' before the initial
1920 `on_failure_jump' instruction of the loop. This
1921 effects a skip over that instruction the first time
1922 we hit that loop. */
1923 GET_BUFFER_SPACE (3);
1924 INSERT_JUMP (dummy_failure_jump, laststart, laststart + 6);
1939 boolean had_char_class = false;
1941 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
1943 /* Ensure that we have enough space to push a charset: the
1944 opcode, the length count, and the bitset; 34 bytes in all. */
1945 GET_BUFFER_SPACE (34);
1949 /* We test `*p == '^' twice, instead of using an if
1950 statement, so we only need one BUF_PUSH. */
1951 BUF_PUSH (*p == '^' ? charset_not : charset);
1955 /* Remember the first position in the bracket expression. */
1958 /* Push the number of bytes in the bitmap. */
1959 BUF_PUSH ((1 << BYTEWIDTH) / BYTEWIDTH);
1961 /* Clear the whole map. */
1962 bzero (b, (1 << BYTEWIDTH) / BYTEWIDTH);
1964 /* charset_not matches newline according to a syntax bit. */
1965 if ((re_opcode_t) b[-2] == charset_not
1966 && (syntax & RE_HAT_LISTS_NOT_NEWLINE))
1967 SET_LIST_BIT ('\n');
1969 /* Read in characters and ranges, setting map bits. */
1972 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
1976 /* \ might escape characters inside [...] and [^...]. */
1977 if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\')
1979 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
1986 /* Could be the end of the bracket expression. If it's
1987 not (i.e., when the bracket expression is `[]' so
1988 far), the ']' character bit gets set way below. */
1989 if (c == ']' && p != p1 + 1)
1992 /* Look ahead to see if it's a range when the last thing
1993 was a character class. */
1994 if (had_char_class && c == '-' && *p != ']')
1995 FREE_STACK_RETURN (REG_ERANGE);
1997 /* Look ahead to see if it's a range when the last thing
1998 was a character: if this is a hyphen not at the
1999 beginning or the end of a list, then it's the range
2002 && !(p - 2 >= pattern && p[-2] == '[')
2003 && !(p - 3 >= pattern && p[-3] == '[' && p[-2] == '^')
2007 = compile_range (&p, pend, translate, syntax, b);
2008 if (ret != REG_NOERROR) FREE_STACK_RETURN (ret);
2011 else if (p[0] == '-' && p[1] != ']')
2012 { /* This handles ranges made up of characters only. */
2015 /* Move past the `-'. */
2018 ret = compile_range (&p, pend, translate, syntax, b);
2019 if (ret != REG_NOERROR) FREE_STACK_RETURN (ret);
2022 /* See if we're at the beginning of a possible character
2025 else if (syntax & RE_CHAR_CLASSES && c == '[' && *p == ':')
2026 { /* Leave room for the null. */
2027 char str[CHAR_CLASS_MAX_LENGTH + 1];
2032 /* If pattern is `[[:'. */
2033 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2038 if (c == ':' || c == ']' || p == pend
2039 || c1 == CHAR_CLASS_MAX_LENGTH)
2045 /* If isn't a word bracketed by `[:' and:`]':
2046 undo the ending character, the letters, and leave
2047 the leading `:' and `[' (but set bits for them). */
2048 if (c == ':' && *p == ']')
2051 boolean is_alnum = STREQ (str, "alnum");
2052 boolean is_alpha = STREQ (str, "alpha");
2053 boolean is_blank = STREQ (str, "blank");
2054 boolean is_cntrl = STREQ (str, "cntrl");
2055 boolean is_digit = STREQ (str, "digit");
2056 boolean is_graph = STREQ (str, "graph");
2057 boolean is_lower = STREQ (str, "lower");
2058 boolean is_print = STREQ (str, "print");
2059 boolean is_punct = STREQ (str, "punct");
2060 boolean is_space = STREQ (str, "space");
2061 boolean is_upper = STREQ (str, "upper");
2062 boolean is_xdigit = STREQ (str, "xdigit");
2064 if (!IS_CHAR_CLASS (str))
2065 FREE_STACK_RETURN (REG_ECTYPE);
2067 /* Throw away the ] at the end of the character
2071 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2073 for (ch = 0; ch < 1 << BYTEWIDTH; ch++)
2075 /* This was split into 3 if's to
2076 avoid an arbitrary limit in some compiler. */
2077 if ( (is_alnum && ISALNUM (ch))
2078 || (is_alpha && ISALPHA (ch))
2079 || (is_blank && ISBLANK (ch))
2080 || (is_cntrl && ISCNTRL (ch)))
2082 if ( (is_digit && ISDIGIT (ch))
2083 || (is_graph && ISGRAPH (ch))
2084 || (is_lower && ISLOWER (ch))
2085 || (is_print && ISPRINT (ch)))
2087 if ( (is_punct && ISPUNCT (ch))
2088 || (is_space && ISSPACE (ch))
2089 || (is_upper && ISUPPER (ch))
2090 || (is_xdigit && ISXDIGIT (ch)))
2093 had_char_class = true;
2102 had_char_class = false;
2107 had_char_class = false;
2112 /* Discard any (non)matching list bytes that are all 0 at the
2113 end of the map. Decrease the map-length byte too. */
2114 while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
2122 if (syntax & RE_NO_BK_PARENS)
2129 if (syntax & RE_NO_BK_PARENS)
2136 if (syntax & RE_NEWLINE_ALT)
2143 if (syntax & RE_NO_BK_VBAR)
2150 if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
2151 goto handle_interval;
2157 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2159 /* Do not translate the character after the \, so that we can
2160 distinguish, e.g., \B from \b, even if we normally would
2161 translate, e.g., B to b. */
2167 if (syntax & RE_NO_BK_PARENS)
2168 goto normal_backslash;
2174 if (COMPILE_STACK_FULL)
2176 RETALLOC (compile_stack.stack, compile_stack.size << 1,
2177 compile_stack_elt_t);
2178 if (compile_stack.stack == NULL) return REG_ESPACE;
2180 compile_stack.size <<= 1;
2183 /* These are the values to restore when we hit end of this
2184 group. They are all relative offsets, so that if the
2185 whole pattern moves because of realloc, they will still
2187 COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
2188 COMPILE_STACK_TOP.fixup_alt_jump
2189 = fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
2190 COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
2191 COMPILE_STACK_TOP.regnum = regnum;
2193 /* We will eventually replace the 0 with the number of
2194 groups inner to this one. But do not push a
2195 start_memory for groups beyond the last one we can
2196 represent in the compiled pattern. */
2197 if (regnum <= MAX_REGNUM)
2199 COMPILE_STACK_TOP.inner_group_offset = b - bufp->buffer + 2;
2200 BUF_PUSH_3 (start_memory, regnum, 0);
2203 compile_stack.avail++;
2208 /* If we've reached MAX_REGNUM groups, then this open
2209 won't actually generate any code, so we'll have to
2210 clear pending_exact explicitly. */
2216 if (syntax & RE_NO_BK_PARENS) goto normal_backslash;
2218 if (COMPILE_STACK_EMPTY)
2219 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
2220 goto normal_backslash;
2222 FREE_STACK_RETURN (REG_ERPAREN);
2226 { /* Push a dummy failure point at the end of the
2227 alternative for a possible future
2228 `pop_failure_jump' to pop. See comments at
2229 `push_dummy_failure' in `re_match_2'. */
2230 BUF_PUSH (push_dummy_failure);
2232 /* We allocated space for this jump when we assigned
2233 to `fixup_alt_jump', in the `handle_alt' case below. */
2234 STORE_JUMP (jump_past_alt, fixup_alt_jump, b - 1);
2237 /* See similar code for backslashed left paren above. */
2238 if (COMPILE_STACK_EMPTY)
2239 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
2242 FREE_STACK_RETURN (REG_ERPAREN);
2244 /* Since we just checked for an empty stack above, this
2245 ``can't happen''. */
2246 assert (compile_stack.avail != 0);
2248 /* We don't just want to restore into `regnum', because
2249 later groups should continue to be numbered higher,
2250 as in `(ab)c(de)' -- the second group is #2. */
2251 regnum_t this_group_regnum;
2253 compile_stack.avail--;
2254 begalt = bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
2256 = COMPILE_STACK_TOP.fixup_alt_jump
2257 ? bufp->buffer + COMPILE_STACK_TOP.fixup_alt_jump - 1
2259 laststart = bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
2260 this_group_regnum = COMPILE_STACK_TOP.regnum;
2261 /* If we've reached MAX_REGNUM groups, then this open
2262 won't actually generate any code, so we'll have to
2263 clear pending_exact explicitly. */
2266 /* We're at the end of the group, so now we know how many
2267 groups were inside this one. */
2268 if (this_group_regnum <= MAX_REGNUM)
2270 unsigned char *inner_group_loc
2271 = bufp->buffer + COMPILE_STACK_TOP.inner_group_offset;
2273 *inner_group_loc = regnum - this_group_regnum;
2274 BUF_PUSH_3 (stop_memory, this_group_regnum,
2275 regnum - this_group_regnum);
2281 case '|': /* `\|'. */
2282 if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
2283 goto normal_backslash;
2285 if (syntax & RE_LIMITED_OPS)
2288 /* Insert before the previous alternative a jump which
2289 jumps to this alternative if the former fails. */
2290 GET_BUFFER_SPACE (3);
2291 INSERT_JUMP (on_failure_jump, begalt, b + 6);
2295 /* The alternative before this one has a jump after it
2296 which gets executed if it gets matched. Adjust that
2297 jump so it will jump to this alternative's analogous
2298 jump (put in below, which in turn will jump to the next
2299 (if any) alternative's such jump, etc.). The last such
2300 jump jumps to the correct final destination. A picture:
2306 If we are at `b', then fixup_alt_jump right now points to a
2307 three-byte space after `a'. We'll put in the jump, set
2308 fixup_alt_jump to right after `b', and leave behind three
2309 bytes which we'll fill in when we get to after `c'. */
2312 STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
2314 /* Mark and leave space for a jump after this alternative,
2315 to be filled in later either by next alternative or
2316 when know we're at the end of a series of alternatives. */
2318 GET_BUFFER_SPACE (3);
2327 /* If \{ is a literal. */
2328 if (!(syntax & RE_INTERVALS)
2329 /* If we're at `\{' and it's not the open-interval
2331 || ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
2332 || (p - 2 == pattern && p == pend))
2333 goto normal_backslash;
2337 /* If got here, then the syntax allows intervals. */
2339 /* At least (most) this many matches must be made. */
2340 int lower_bound = -1, upper_bound = -1;
2342 beg_interval = p - 1;
2346 if (syntax & RE_NO_BK_BRACES)
2347 goto unfetch_interval;
2349 FREE_STACK_RETURN (REG_EBRACE);
2352 GET_UNSIGNED_NUMBER (lower_bound);
2356 GET_UNSIGNED_NUMBER (upper_bound);
2357 if (upper_bound < 0) upper_bound = RE_DUP_MAX;
2360 /* Interval such as `{1}' => match exactly once. */
2361 upper_bound = lower_bound;
2363 if (lower_bound < 0 || upper_bound > RE_DUP_MAX
2364 || lower_bound > upper_bound)
2366 if (syntax & RE_NO_BK_BRACES)
2367 goto unfetch_interval;
2369 FREE_STACK_RETURN (REG_BADBR);
2372 if (!(syntax & RE_NO_BK_BRACES))
2374 if (c != '\\') FREE_STACK_RETURN (REG_EBRACE);
2381 if (syntax & RE_NO_BK_BRACES)
2382 goto unfetch_interval;
2384 FREE_STACK_RETURN (REG_BADBR);
2387 /* We just parsed a valid interval. */
2389 /* If it's invalid to have no preceding re. */
2392 if (syntax & RE_CONTEXT_INVALID_OPS)
2393 FREE_STACK_RETURN (REG_BADRPT);
2394 else if (syntax & RE_CONTEXT_INDEP_OPS)
2397 goto unfetch_interval;
2400 /* If the upper bound is zero, don't want to succeed at
2401 all; jump from `laststart' to `b + 3', which will be
2402 the end of the buffer after we insert the jump. */
2403 if (upper_bound == 0)
2405 GET_BUFFER_SPACE (3);
2406 INSERT_JUMP (jump, laststart, b + 3);
2410 /* Otherwise, we have a nontrivial interval. When
2411 we're all done, the pattern will look like:
2412 set_number_at <jump count> <upper bound>
2413 set_number_at <succeed_n count> <lower bound>
2414 succeed_n <after jump addr> <succeed_n count>
2416 jump_n <succeed_n addr> <jump count>
2417 (The upper bound and `jump_n' are omitted if
2418 `upper_bound' is 1, though.) */
2420 { /* If the upper bound is > 1, we need to insert
2421 more at the end of the loop. */
2422 unsigned nbytes = 10 + (upper_bound > 1) * 10;
2424 GET_BUFFER_SPACE (nbytes);
2426 /* Initialize lower bound of the `succeed_n', even
2427 though it will be set during matching by its
2428 attendant `set_number_at' (inserted next),
2429 because `re_compile_fastmap' needs to know.
2430 Jump to the `jump_n' we might insert below. */
2431 INSERT_JUMP2 (succeed_n, laststart,
2432 b + 5 + (upper_bound > 1) * 5,
2436 /* Code to initialize the lower bound. Insert
2437 before the `succeed_n'. The `5' is the last two
2438 bytes of this `set_number_at', plus 3 bytes of
2439 the following `succeed_n'. */
2440 insert_op2 (set_number_at, laststart, 5, lower_bound, b);
2443 if (upper_bound > 1)
2444 { /* More than one repetition is allowed, so
2445 append a backward jump to the `succeed_n'
2446 that starts this interval.
2448 When we've reached this during matching,
2449 we'll have matched the interval once, so
2450 jump back only `upper_bound - 1' times. */
2451 STORE_JUMP2 (jump_n, b, laststart + 5,
2455 /* The location we want to set is the second
2456 parameter of the `jump_n'; that is `b-2' as
2457 an absolute address. `laststart' will be
2458 the `set_number_at' we're about to insert;
2459 `laststart+3' the number to set, the source
2460 for the relative address. But we are
2461 inserting into the middle of the pattern --
2462 so everything is getting moved up by 5.
2463 Conclusion: (b - 2) - (laststart + 3) + 5,
2464 i.e., b - laststart.
2466 We insert this at the beginning of the loop
2467 so that if we fail during matching, we'll
2468 reinitialize the bounds. */
2469 insert_op2 (set_number_at, laststart, b - laststart,
2470 upper_bound - 1, b);
2475 beg_interval = NULL;
2480 /* If an invalid interval, match the characters as literals. */
2481 assert (beg_interval);
2483 beg_interval = NULL;
2485 /* normal_char and normal_backslash need `c'. */
2488 if (!(syntax & RE_NO_BK_BRACES))
2490 if (p > pattern && p[-1] == '\\')
2491 goto normal_backslash;
2496 /* There is no way to specify the before_dot and after_dot
2497 operators. rms says this is ok. --karl */
2505 BUF_PUSH_2 (syntaxspec, syntax_spec_code[c]);
2511 BUF_PUSH_2 (notsyntaxspec, syntax_spec_code[c]);
2518 BUF_PUSH (wordchar);
2524 BUF_PUSH (notwordchar);
2537 BUF_PUSH (wordbound);
2541 BUF_PUSH (notwordbound);
2552 case '1': case '2': case '3': case '4': case '5':
2553 case '6': case '7': case '8': case '9':
2554 if (syntax & RE_NO_BK_REFS)
2560 FREE_STACK_RETURN (REG_ESUBREG);
2562 /* Can't back reference to a subexpression if inside of it. */
2563 if (group_in_compile_stack (compile_stack, c1))
2567 BUF_PUSH_2 (duplicate, c1);
2573 if (syntax & RE_BK_PLUS_QM)
2576 goto normal_backslash;
2580 /* You might think it would be useful for \ to mean
2581 not to translate; but if we don't translate it
2582 it will never match anything. */
2590 /* Expects the character in `c'. */
2592 /* If no exactn currently being built. */
2595 /* If last exactn not at current position. */
2596 || pending_exact + *pending_exact + 1 != b
2598 /* We have only one byte following the exactn for the count. */
2599 || *pending_exact == (1 << BYTEWIDTH) - 1
2601 /* If followed by a repetition operator. */
2602 || *p == '*' || *p == '^'
2603 || ((syntax & RE_BK_PLUS_QM)
2604 ? *p == '\\' && (p[1] == '+' || p[1] == '?')
2605 : (*p == '+' || *p == '?'))
2606 || ((syntax & RE_INTERVALS)
2607 && ((syntax & RE_NO_BK_BRACES)
2609 : (p[0] == '\\' && p[1] == '{'))))
2611 /* Start building a new exactn. */
2615 BUF_PUSH_2 (exactn, 0);
2616 pending_exact = b - 1;
2623 } /* while p != pend */
2626 /* Through the pattern now. */
2629 STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
2631 if (!COMPILE_STACK_EMPTY)
2632 FREE_STACK_RETURN (REG_EPAREN);
2634 /* If we don't want backtracking, force success
2635 the first time we reach the end of the compiled pattern. */
2636 if (syntax & RE_NO_POSIX_BACKTRACKING)
2639 free (compile_stack.stack);
2641 /* We have succeeded; set the length of the buffer. */
2642 bufp->used = b - bufp->buffer;
2647 DEBUG_PRINT1 ("\nCompiled pattern: \n");
2648 print_compiled_pattern (bufp);
2652 #ifndef MATCH_MAY_ALLOCATE
2653 /* Initialize the failure stack to the largest possible stack. This
2654 isn't necessary unless we're trying to avoid calling alloca in
2655 the search and match routines. */
2657 int num_regs = bufp->re_nsub + 1;
2659 /* Since DOUBLE_FAIL_STACK refuses to double only if the current size
2660 is strictly greater than re_max_failures, the largest possible stack
2661 is 2 * re_max_failures failure points. */
2662 if (fail_stack.size < (2 * re_max_failures * MAX_FAILURE_ITEMS))
2664 fail_stack.size = (2 * re_max_failures * MAX_FAILURE_ITEMS);
2667 if (! fail_stack.stack)
2669 = (fail_stack_elt_t *) xmalloc (fail_stack.size
2670 * sizeof (fail_stack_elt_t));
2673 = (fail_stack_elt_t *) xrealloc (fail_stack.stack,
2675 * sizeof (fail_stack_elt_t)));
2676 #else /* not emacs */
2677 if (! fail_stack.stack)
2679 = (fail_stack_elt_t *) malloc (fail_stack.size
2680 * sizeof (fail_stack_elt_t));
2683 = (fail_stack_elt_t *) realloc (fail_stack.stack,
2685 * sizeof (fail_stack_elt_t)));
2686 #endif /* not emacs */
2689 regex_grow_registers (num_regs);
2691 #endif /* not MATCH_MAY_ALLOCATE */
2694 } /* regex_compile */
2696 /* Subroutines for `regex_compile'. */
2698 /* Store OP at LOC followed by two-byte integer parameter ARG. */
2701 store_op1 (op, loc, arg)
2706 *loc = (unsigned char) op;
2707 STORE_NUMBER (loc + 1, arg);
2711 /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
2714 store_op2 (op, loc, arg1, arg2)
2719 *loc = (unsigned char) op;
2720 STORE_NUMBER (loc + 1, arg1);
2721 STORE_NUMBER (loc + 3, arg2);
2725 /* Copy the bytes from LOC to END to open up three bytes of space at LOC
2726 for OP followed by two-byte integer parameter ARG. */
2729 insert_op1 (op, loc, arg, end)
2735 register unsigned char *pfrom = end;
2736 register unsigned char *pto = end + 3;
2738 while (pfrom != loc)
2741 store_op1 (op, loc, arg);
2745 /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
2748 insert_op2 (op, loc, arg1, arg2, end)
2754 register unsigned char *pfrom = end;
2755 register unsigned char *pto = end + 5;
2757 while (pfrom != loc)
2760 store_op2 (op, loc, arg1, arg2);
2764 /* P points to just after a ^ in PATTERN. Return true if that ^ comes
2765 after an alternative or a begin-subexpression. We assume there is at
2766 least one character before the ^. */
2769 at_begline_loc_p (pattern, p, syntax)
2770 const char *pattern, *p;
2771 reg_syntax_t syntax;
2773 const char *prev = p - 2;
2774 boolean prev_prev_backslash = prev > pattern && prev[-1] == '\\';
2777 /* After a subexpression? */
2778 (*prev == '(' && (syntax & RE_NO_BK_PARENS || prev_prev_backslash))
2779 /* After an alternative? */
2780 || (*prev == '|' && (syntax & RE_NO_BK_VBAR || prev_prev_backslash));
2784 /* The dual of at_begline_loc_p. This one is for $. We assume there is
2785 at least one character after the $, i.e., `P < PEND'. */
2788 at_endline_loc_p (p, pend, syntax)
2789 const char *p, *pend;
2792 const char *next = p;
2793 boolean next_backslash = *next == '\\';
2794 const char *next_next = p + 1 < pend ? p + 1 : 0;
2797 /* Before a subexpression? */
2798 (syntax & RE_NO_BK_PARENS ? *next == ')'
2799 : next_backslash && next_next && *next_next == ')')
2800 /* Before an alternative? */
2801 || (syntax & RE_NO_BK_VBAR ? *next == '|'
2802 : next_backslash && next_next && *next_next == '|');
2806 /* Returns true if REGNUM is in one of COMPILE_STACK's elements and
2807 false if it's not. */
2810 group_in_compile_stack (compile_stack, regnum)
2811 compile_stack_type compile_stack;
2816 for (this_element = compile_stack.avail - 1;
2819 if (compile_stack.stack[this_element].regnum == regnum)
2826 /* Read the ending character of a range (in a bracket expression) from the
2827 uncompiled pattern *P_PTR (which ends at PEND). We assume the
2828 starting character is in `P[-2]'. (`P[-1]' is the character `-'.)
2829 Then we set the translation of all bits between the starting and
2830 ending characters (inclusive) in the compiled pattern B.
2832 Return an error code.
2834 We use these short variable names so we can use the same macros as
2835 `regex_compile' itself. */
2837 static reg_errcode_t
2838 compile_range (p_ptr, pend, translate, syntax, b)
2839 const char **p_ptr, *pend;
2840 RE_TRANSLATE_TYPE translate;
2841 reg_syntax_t syntax;
2846 const char *p = *p_ptr;
2847 int range_start, range_end;
2852 /* Even though the pattern is a signed `char *', we need to fetch
2853 with unsigned char *'s; if the high bit of the pattern character
2854 is set, the range endpoints will be negative if we fetch using a
2857 We also want to fetch the endpoints without translating them; the
2858 appropriate translation is done in the bit-setting loop below. */
2859 /* The SVR4 compiler on the 3B2 had trouble with unsigned const char *. */
2860 range_start = ((const unsigned char *) p)[-2];
2861 range_end = ((const unsigned char *) p)[0];
2863 /* Have to increment the pointer into the pattern string, so the
2864 caller isn't still at the ending character. */
2867 /* If the start is after the end, the range is empty. */
2868 if (range_start > range_end)
2869 return syntax & RE_NO_EMPTY_RANGES ? REG_ERANGE : REG_NOERROR;
2871 /* Here we see why `this_char' has to be larger than an `unsigned
2872 char' -- the range is inclusive, so if `range_end' == 0xff
2873 (assuming 8-bit characters), we would otherwise go into an infinite
2874 loop, since all characters <= 0xff. */
2875 for (this_char = range_start; this_char <= range_end; this_char++)
2877 SET_LIST_BIT (TRANSLATE (this_char));
2883 /* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
2884 BUFP. A fastmap records which of the (1 << BYTEWIDTH) possible
2885 characters can start a string that matches the pattern. This fastmap
2886 is used by re_search to skip quickly over impossible starting points.
2888 The caller must supply the address of a (1 << BYTEWIDTH)-byte data
2889 area as BUFP->fastmap.
2891 We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
2894 Returns 0 if we succeed, -2 if an internal error. */
2897 re_compile_fastmap (bufp)
2898 struct re_pattern_buffer *bufp;
2901 #ifdef MATCH_MAY_ALLOCATE
2902 fail_stack_type fail_stack;
2904 #ifndef REGEX_MALLOC
2907 /* We don't push any register information onto the failure stack. */
2908 unsigned num_regs = 0;
2910 register char *fastmap = bufp->fastmap;
2911 unsigned char *pattern = bufp->buffer;
2912 unsigned long size = bufp->used;
2913 unsigned char *p = pattern;
2914 register unsigned char *pend = pattern + size;
2916 /* This holds the pointer to the failure stack, when
2917 it is allocated relocatably. */
2919 fail_stack_elt_t *failure_stack_ptr;
2922 /* Assume that each path through the pattern can be null until
2923 proven otherwise. We set this false at the bottom of switch
2924 statement, to which we get only if a particular path doesn't
2925 match the empty string. */
2926 boolean path_can_be_null = true;
2928 /* We aren't doing a `succeed_n' to begin with. */
2929 boolean succeed_n_p = false;
2931 assert (fastmap != NULL && p != NULL);
2934 bzero (fastmap, 1 << BYTEWIDTH); /* Assume nothing's valid. */
2935 bufp->fastmap_accurate = 1; /* It will be when we're done. */
2936 bufp->can_be_null = 0;
2940 if (p == pend || *p == succeed)
2942 /* We have reached the (effective) end of pattern. */
2943 if (!FAIL_STACK_EMPTY ())
2945 bufp->can_be_null |= path_can_be_null;
2947 /* Reset for next path. */
2948 path_can_be_null = true;
2950 p = fail_stack.stack[--fail_stack.avail].pointer;
2958 /* We should never be about to go beyond the end of the pattern. */
2961 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
2964 /* I guess the idea here is to simply not bother with a fastmap
2965 if a backreference is used, since it's too hard to figure out
2966 the fastmap for the corresponding group. Setting
2967 `can_be_null' stops `re_search_2' from using the fastmap, so
2968 that is all we do. */
2970 bufp->can_be_null = 1;
2974 /* Following are the cases which match a character. These end
2983 for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
2984 if (p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH)))
2990 /* Chars beyond end of map must be allowed. */
2991 for (j = *p * BYTEWIDTH; j < (1 << BYTEWIDTH); j++)
2994 for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
2995 if (!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))))
3001 for (j = 0; j < (1 << BYTEWIDTH); j++)
3002 if (SYNTAX (j) == Sword)
3008 for (j = 0; j < (1 << BYTEWIDTH); j++)
3009 if (SYNTAX (j) != Sword)
3016 int fastmap_newline = fastmap['\n'];
3018 /* `.' matches anything ... */
3019 for (j = 0; j < (1 << BYTEWIDTH); j++)
3022 /* ... except perhaps newline. */
3023 if (!(bufp->syntax & RE_DOT_NEWLINE))
3024 fastmap['\n'] = fastmap_newline;
3026 /* Return if we have already set `can_be_null'; if we have,
3027 then the fastmap is irrelevant. Something's wrong here. */
3028 else if (bufp->can_be_null)
3031 /* Otherwise, have to check alternative paths. */
3038 for (j = 0; j < (1 << BYTEWIDTH); j++)
3039 if (SYNTAX (j) == (enum syntaxcode) k)
3046 for (j = 0; j < (1 << BYTEWIDTH); j++)
3047 if (SYNTAX (j) != (enum syntaxcode) k)
3052 /* All cases after this match the empty string. These end with
3072 case push_dummy_failure:
3077 case pop_failure_jump:
3078 case maybe_pop_jump:
3081 case dummy_failure_jump:
3082 EXTRACT_NUMBER_AND_INCR (j, p);
3087 /* Jump backward implies we just went through the body of a
3088 loop and matched nothing. Opcode jumped to should be
3089 `on_failure_jump' or `succeed_n'. Just treat it like an
3090 ordinary jump. For a * loop, it has pushed its failure
3091 point already; if so, discard that as redundant. */
3092 if ((re_opcode_t) *p != on_failure_jump
3093 && (re_opcode_t) *p != succeed_n)
3097 EXTRACT_NUMBER_AND_INCR (j, p);
3100 /* If what's on the stack is where we are now, pop it. */
3101 if (!FAIL_STACK_EMPTY ()
3102 && fail_stack.stack[fail_stack.avail - 1].pointer == p)
3108 case on_failure_jump:
3109 case on_failure_keep_string_jump:
3110 handle_on_failure_jump:
3111 EXTRACT_NUMBER_AND_INCR (j, p);
3113 /* For some patterns, e.g., `(a?)?', `p+j' here points to the
3114 end of the pattern. We don't want to push such a point,
3115 since when we restore it above, entering the switch will
3116 increment `p' past the end of the pattern. We don't need
3117 to push such a point since we obviously won't find any more
3118 fastmap entries beyond `pend'. Such a pattern can match
3119 the null string, though. */
3122 if (!PUSH_PATTERN_OP (p + j, fail_stack))
3124 RESET_FAIL_STACK ();
3129 bufp->can_be_null = 1;
3133 EXTRACT_NUMBER_AND_INCR (k, p); /* Skip the n. */
3134 succeed_n_p = false;
3141 /* Get to the number of times to succeed. */
3144 /* Increment p past the n for when k != 0. */
3145 EXTRACT_NUMBER_AND_INCR (k, p);
3149 succeed_n_p = true; /* Spaghetti code alert. */
3150 goto handle_on_failure_jump;
3167 abort (); /* We have listed all the cases. */
3170 /* Getting here means we have found the possible starting
3171 characters for one path of the pattern -- and that the empty
3172 string does not match. We need not follow this path further.
3173 Instead, look at the next alternative (remembered on the
3174 stack), or quit if no more. The test at the top of the loop
3175 does these things. */
3176 path_can_be_null = false;
3180 /* Set `can_be_null' for the last path (also the first path, if the
3181 pattern is empty). */
3182 bufp->can_be_null |= path_can_be_null;
3185 RESET_FAIL_STACK ();
3187 } /* re_compile_fastmap */
3189 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
3190 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
3191 this memory for recording register information. STARTS and ENDS
3192 must be allocated using the malloc library routine, and must each
3193 be at least NUM_REGS * sizeof (regoff_t) bytes long.
3195 If NUM_REGS == 0, then subsequent matches should allocate their own
3198 Unless this function is called, the first search or match using
3199 PATTERN_BUFFER will allocate its own register data, without
3200 freeing the old data. */
3203 re_set_registers (bufp, regs, num_regs, starts, ends)
3204 struct re_pattern_buffer *bufp;
3205 struct re_registers *regs;
3207 regoff_t *starts, *ends;
3211 bufp->regs_allocated = REGS_REALLOCATE;
3212 regs->num_regs = num_regs;
3213 regs->start = starts;
3218 bufp->regs_allocated = REGS_UNALLOCATED;
3220 regs->start = regs->end = (regoff_t *) 0;
3224 /* Searching routines. */
3226 /* Like re_search_2, below, but only one string is specified, and
3227 doesn't let you say where to stop matching. */
3230 re_search (bufp, string, size, startpos, range, regs)
3231 struct re_pattern_buffer *bufp;
3233 int size, startpos, range;
3234 struct re_registers *regs;
3236 return re_search_2 (bufp, NULL, 0, string, size, startpos, range,
3241 /* Using the compiled pattern in BUFP->buffer, first tries to match the
3242 virtual concatenation of STRING1 and STRING2, starting first at index
3243 STARTPOS, then at STARTPOS + 1, and so on.
3245 STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
3247 RANGE is how far to scan while trying to match. RANGE = 0 means try
3248 only at STARTPOS; in general, the last start tried is STARTPOS +
3251 In REGS, return the indices of the virtual concatenation of STRING1
3252 and STRING2 that matched the entire BUFP->buffer and its contained
3255 Do not consider matching one past the index STOP in the virtual
3256 concatenation of STRING1 and STRING2.
3258 We return either the position in the strings at which the match was
3259 found, -1 if no match, or -2 if error (such as failure
3263 re_search_2 (bufp, string1, size1, string2, size2, startpos, range, regs, stop)
3264 struct re_pattern_buffer *bufp;
3265 const char *string1, *string2;
3269 struct re_registers *regs;
3273 register char *fastmap = bufp->fastmap;
3274 register RE_TRANSLATE_TYPE translate = bufp->translate;
3275 int total_size = size1 + size2;
3276 int endpos = startpos + range;
3278 /* Check for out-of-range STARTPOS. */
3279 if (startpos < 0 || startpos > total_size)
3282 /* Fix up RANGE if it might eventually take us outside
3283 the virtual concatenation of STRING1 and STRING2.
3284 Make sure we won't move STARTPOS below 0 or above TOTAL_SIZE. */
3286 range = 0 - startpos;
3287 else if (endpos > total_size)
3288 range = total_size - startpos;
3290 /* If the search isn't to be a backwards one, don't waste time in a
3291 search for a pattern that must be anchored. */
3292 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == begbuf && range > 0)
3301 /* In a forward search for something that starts with \=.
3302 don't keep searching past point. */
3303 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == at_dot && range > 0)
3305 range = PT - startpos;
3311 /* Update the fastmap now if not correct already. */
3312 if (fastmap && !bufp->fastmap_accurate)
3313 if (re_compile_fastmap (bufp) == -2)
3316 /* Loop through the string, looking for a place to start matching. */
3319 /* If a fastmap is supplied, skip quickly over characters that
3320 cannot be the start of a match. If the pattern can match the
3321 null string, however, we don't need to skip characters; we want
3322 the first null string. */
3323 if (fastmap && startpos < total_size && !bufp->can_be_null)
3325 if (range > 0) /* Searching forwards. */
3327 register const char *d;
3328 register int lim = 0;
3331 if (startpos < size1 && startpos + range >= size1)
3332 lim = range - (size1 - startpos);
3334 d = (startpos >= size1 ? string2 - size1 : string1) + startpos;
3336 /* Written out as an if-else to avoid testing `translate'
3340 && !fastmap[(unsigned char)
3341 translate[(unsigned char) *d++]])
3344 while (range > lim && !fastmap[(unsigned char) *d++])
3347 startpos += irange - range;
3349 else /* Searching backwards. */
3351 register char c = (size1 == 0 || startpos >= size1
3352 ? string2[startpos - size1]
3353 : string1[startpos]);
3355 if (!fastmap[(unsigned char) TRANSLATE (c)])
3360 /* If can't match the null string, and that's all we have left, fail. */
3361 if (range >= 0 && startpos == total_size && fastmap
3362 && !bufp->can_be_null)
3365 val = re_match_2_internal (bufp, string1, size1, string2, size2,
3366 startpos, regs, stop);
3367 #ifndef REGEX_MALLOC
3396 /* Declarations and macros for re_match_2. */
3398 static int bcmp_translate ();
3399 static boolean alt_match_null_string_p (),
3400 common_op_match_null_string_p (),
3401 group_match_null_string_p ();
3403 /* This converts PTR, a pointer into one of the search strings `string1'
3404 and `string2' into an offset from the beginning of that string. */
3405 #define POINTER_TO_OFFSET(ptr) \
3406 (FIRST_STRING_P (ptr) \
3407 ? ((regoff_t) ((ptr) - string1)) \
3408 : ((regoff_t) ((ptr) - string2 + size1)))
3410 /* Macros for dealing with the split strings in re_match_2. */
3412 #define MATCHING_IN_FIRST_STRING (dend == end_match_1)
3414 /* Call before fetching a character with *d. This switches over to
3415 string2 if necessary. */
3416 #define PREFETCH() \
3419 /* End of string2 => fail. */ \
3420 if (dend == end_match_2) \
3422 /* End of string1 => advance to string2. */ \
3424 dend = end_match_2; \
3428 /* Test if at very beginning or at very end of the virtual concatenation
3429 of `string1' and `string2'. If only one string, it's `string2'. */
3430 #define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
3431 #define AT_STRINGS_END(d) ((d) == end2)
3434 /* Test if D points to a character which is word-constituent. We have
3435 two special cases to check for: if past the end of string1, look at
3436 the first character in string2; and if before the beginning of
3437 string2, look at the last character in string1. */
3438 #define WORDCHAR_P(d) \
3439 (SYNTAX ((d) == end1 ? *string2 \
3440 : (d) == string2 - 1 ? *(end1 - 1) : *(d)) \
3443 /* Test if the character before D and the one at D differ with respect
3444 to being word-constituent. */
3445 #define AT_WORD_BOUNDARY(d) \
3446 (AT_STRINGS_BEG (d) || AT_STRINGS_END (d) \
3447 || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
3450 /* Free everything we malloc. */
3451 #ifdef MATCH_MAY_ALLOCATE
3452 #define FREE_VAR(var) if (var) REGEX_FREE (var); var = NULL
3453 #define FREE_VARIABLES() \
3455 REGEX_FREE_STACK (fail_stack.stack); \
3456 FREE_VAR (regstart); \
3457 FREE_VAR (regend); \
3458 FREE_VAR (old_regstart); \
3459 FREE_VAR (old_regend); \
3460 FREE_VAR (best_regstart); \
3461 FREE_VAR (best_regend); \
3462 FREE_VAR (reg_info); \
3463 FREE_VAR (reg_dummy); \
3464 FREE_VAR (reg_info_dummy); \
3467 #define FREE_VARIABLES() ((void)0) /* Do nothing! But inhibit gcc warning. */
3468 #endif /* not MATCH_MAY_ALLOCATE */
3470 /* These values must meet several constraints. They must not be valid
3471 register values; since we have a limit of 255 registers (because
3472 we use only one byte in the pattern for the register number), we can
3473 use numbers larger than 255. They must differ by 1, because of
3474 NUM_FAILURE_ITEMS above. And the value for the lowest register must
3475 be larger than the value for the highest register, so we do not try
3476 to actually save any registers when none are active. */
3477 #define NO_HIGHEST_ACTIVE_REG (1 << BYTEWIDTH)
3478 #define NO_LOWEST_ACTIVE_REG (NO_HIGHEST_ACTIVE_REG + 1)
3480 /* Matching routines. */
3482 #ifndef emacs /* Emacs never uses this. */
3483 /* re_match is like re_match_2 except it takes only a single string. */
3486 re_match (bufp, string, size, pos, regs)
3487 struct re_pattern_buffer *bufp;
3490 struct re_registers *regs;
3492 int result = re_match_2_internal (bufp, NULL, 0, string, size,
3497 #endif /* not emacs */
3500 /* re_match_2 matches the compiled pattern in BUFP against the
3501 the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
3502 and SIZE2, respectively). We start matching at POS, and stop
3505 If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
3506 store offsets for the substring each group matched in REGS. See the
3507 documentation for exactly how many groups we fill.
3509 We return -1 if no match, -2 if an internal error (such as the
3510 failure stack overflowing). Otherwise, we return the length of the
3511 matched substring. */
3514 re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
3515 struct re_pattern_buffer *bufp;
3516 const char *string1, *string2;
3519 struct re_registers *regs;
3522 int result = re_match_2_internal (bufp, string1, size1, string2, size2,
3528 /* This is a separate function so that we can force an alloca cleanup
3531 re_match_2_internal (bufp, string1, size1, string2, size2, pos, regs, stop)
3532 struct re_pattern_buffer *bufp;
3533 const char *string1, *string2;
3536 struct re_registers *regs;
3539 /* General temporaries. */
3543 /* Just past the end of the corresponding string. */
3544 const char *end1, *end2;
3546 /* Pointers into string1 and string2, just past the last characters in
3547 each to consider matching. */
3548 const char *end_match_1, *end_match_2;
3550 /* Where we are in the data, and the end of the current string. */
3551 const char *d, *dend;
3553 /* Where we are in the pattern, and the end of the pattern. */
3554 unsigned char *p = bufp->buffer;
3555 register unsigned char *pend = p + bufp->used;
3557 /* Mark the opcode just after a start_memory, so we can test for an
3558 empty subpattern when we get to the stop_memory. */
3559 unsigned char *just_past_start_mem = 0;
3561 /* We use this to map every character in the string. */
3562 RE_TRANSLATE_TYPE translate = bufp->translate;
3564 /* Failure point stack. Each place that can handle a failure further
3565 down the line pushes a failure point on this stack. It consists of
3566 restart, regend, and reg_info for all registers corresponding to
3567 the subexpressions we're currently inside, plus the number of such
3568 registers, and, finally, two char *'s. The first char * is where
3569 to resume scanning the pattern; the second one is where to resume
3570 scanning the strings. If the latter is zero, the failure point is
3571 a ``dummy''; if a failure happens and the failure point is a dummy,
3572 it gets discarded and the next next one is tried. */
3573 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
3574 fail_stack_type fail_stack;
3577 static unsigned failure_id = 0;
3578 unsigned nfailure_points_pushed = 0, nfailure_points_popped = 0;
3581 /* This holds the pointer to the failure stack, when
3582 it is allocated relocatably. */
3584 fail_stack_elt_t *failure_stack_ptr;
3587 /* We fill all the registers internally, independent of what we
3588 return, for use in backreferences. The number here includes
3589 an element for register zero. */
3590 unsigned num_regs = bufp->re_nsub + 1;
3592 /* The currently active registers. */
3593 unsigned lowest_active_reg = NO_LOWEST_ACTIVE_REG;
3594 unsigned highest_active_reg = NO_HIGHEST_ACTIVE_REG;
3596 /* Information on the contents of registers. These are pointers into
3597 the input strings; they record just what was matched (on this
3598 attempt) by a subexpression part of the pattern, that is, the
3599 regnum-th regstart pointer points to where in the pattern we began
3600 matching and the regnum-th regend points to right after where we
3601 stopped matching the regnum-th subexpression. (The zeroth register
3602 keeps track of what the whole pattern matches.) */
3603 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3604 const char **regstart, **regend;
3607 /* If a group that's operated upon by a repetition operator fails to
3608 match anything, then the register for its start will need to be
3609 restored because it will have been set to wherever in the string we
3610 are when we last see its open-group operator. Similarly for a
3612 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3613 const char **old_regstart, **old_regend;
3616 /* The is_active field of reg_info helps us keep track of which (possibly
3617 nested) subexpressions we are currently in. The matched_something
3618 field of reg_info[reg_num] helps us tell whether or not we have
3619 matched any of the pattern so far this time through the reg_num-th
3620 subexpression. These two fields get reset each time through any
3621 loop their register is in. */
3622 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
3623 register_info_type *reg_info;
3626 /* The following record the register info as found in the above
3627 variables when we find a match better than any we've seen before.
3628 This happens as we backtrack through the failure points, which in
3629 turn happens only if we have not yet matched the entire string. */
3630 unsigned best_regs_set = false;
3631 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3632 const char **best_regstart, **best_regend;
3635 /* Logically, this is `best_regend[0]'. But we don't want to have to
3636 allocate space for that if we're not allocating space for anything
3637 else (see below). Also, we never need info about register 0 for
3638 any of the other register vectors, and it seems rather a kludge to
3639 treat `best_regend' differently than the rest. So we keep track of
3640 the end of the best match so far in a separate variable. We
3641 initialize this to NULL so that when we backtrack the first time
3642 and need to test it, it's not garbage. */
3643 const char *match_end = NULL;
3645 /* This helps SET_REGS_MATCHED avoid doing redundant work. */
3646 int set_regs_matched_done = 0;
3648 /* Used when we pop values we don't care about. */
3649 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3650 const char **reg_dummy;
3651 register_info_type *reg_info_dummy;
3655 /* Counts the total number of registers pushed. */
3656 unsigned num_regs_pushed = 0;
3659 DEBUG_PRINT1 ("\n\nEntering re_match_2.\n");
3663 #ifdef MATCH_MAY_ALLOCATE
3664 /* Do not bother to initialize all the register variables if there are
3665 no groups in the pattern, as it takes a fair amount of time. If
3666 there are groups, we include space for register 0 (the whole
3667 pattern), even though we never use it, since it simplifies the
3668 array indexing. We should fix this. */
3671 regstart = REGEX_TALLOC (num_regs, const char *);
3672 regend = REGEX_TALLOC (num_regs, const char *);
3673 old_regstart = REGEX_TALLOC (num_regs, const char *);
3674 old_regend = REGEX_TALLOC (num_regs, const char *);
3675 best_regstart = REGEX_TALLOC (num_regs, const char *);
3676 best_regend = REGEX_TALLOC (num_regs, const char *);
3677 reg_info = REGEX_TALLOC (num_regs, register_info_type);
3678 reg_dummy = REGEX_TALLOC (num_regs, const char *);
3679 reg_info_dummy = REGEX_TALLOC (num_regs, register_info_type);
3681 if (!(regstart && regend && old_regstart && old_regend && reg_info
3682 && best_regstart && best_regend && reg_dummy && reg_info_dummy))
3690 /* We must initialize all our variables to NULL, so that
3691 `FREE_VARIABLES' doesn't try to free them. */
3692 regstart = regend = old_regstart = old_regend = best_regstart
3693 = best_regend = reg_dummy = NULL;
3694 reg_info = reg_info_dummy = (register_info_type *) NULL;
3696 #endif /* MATCH_MAY_ALLOCATE */
3698 /* The starting position is bogus. */
3699 if (pos < 0 || pos > size1 + size2)
3705 /* Initialize subexpression text positions to -1 to mark ones that no
3706 start_memory/stop_memory has been seen for. Also initialize the
3707 register information struct. */
3708 for (mcnt = 1; mcnt < num_regs; mcnt++)
3710 regstart[mcnt] = regend[mcnt]
3711 = old_regstart[mcnt] = old_regend[mcnt] = REG_UNSET_VALUE;
3713 REG_MATCH_NULL_STRING_P (reg_info[mcnt]) = MATCH_NULL_UNSET_VALUE;
3714 IS_ACTIVE (reg_info[mcnt]) = 0;
3715 MATCHED_SOMETHING (reg_info[mcnt]) = 0;
3716 EVER_MATCHED_SOMETHING (reg_info[mcnt]) = 0;
3719 /* We move `string1' into `string2' if the latter's empty -- but not if
3720 `string1' is null. */
3721 if (size2 == 0 && string1 != NULL)
3728 end1 = string1 + size1;
3729 end2 = string2 + size2;
3731 /* Compute where to stop matching, within the two strings. */
3734 end_match_1 = string1 + stop;
3735 end_match_2 = string2;
3740 end_match_2 = string2 + stop - size1;
3743 /* `p' scans through the pattern as `d' scans through the data.
3744 `dend' is the end of the input string that `d' points within. `d'
3745 is advanced into the following input string whenever necessary, but
3746 this happens before fetching; therefore, at the beginning of the
3747 loop, `d' can be pointing at the end of a string, but it cannot
3749 if (size1 > 0 && pos <= size1)
3756 d = string2 + pos - size1;
3760 DEBUG_PRINT1 ("The compiled pattern is: ");
3761 DEBUG_PRINT_COMPILED_PATTERN (bufp, p, pend);
3762 DEBUG_PRINT1 ("The string to match is: `");
3763 DEBUG_PRINT_DOUBLE_STRING (d, string1, size1, string2, size2);
3764 DEBUG_PRINT1 ("'\n");
3766 /* This loops over pattern commands. It exits by returning from the
3767 function if the match is complete, or it drops through if the match
3768 fails at this starting point in the input data. */
3771 DEBUG_PRINT2 ("\n0x%x: ", p);
3774 { /* End of pattern means we might have succeeded. */
3775 DEBUG_PRINT1 ("end of pattern ... ");
3777 /* If we haven't matched the entire string, and we want the
3778 longest match, try backtracking. */
3779 if (d != end_match_2)
3781 /* 1 if this match ends in the same string (string1 or string2)
3782 as the best previous match. */
3783 boolean same_str_p = (FIRST_STRING_P (match_end)
3784 == MATCHING_IN_FIRST_STRING);
3785 /* 1 if this match is the best seen so far. */
3786 boolean best_match_p;
3788 /* AIX compiler got confused when this was combined
3789 with the previous declaration. */
3791 best_match_p = d > match_end;
3793 best_match_p = !MATCHING_IN_FIRST_STRING;
3795 DEBUG_PRINT1 ("backtracking.\n");
3797 if (!FAIL_STACK_EMPTY ())
3798 { /* More failure points to try. */
3800 /* If exceeds best match so far, save it. */
3801 if (!best_regs_set || best_match_p)
3803 best_regs_set = true;
3806 DEBUG_PRINT1 ("\nSAVING match as best so far.\n");
3808 for (mcnt = 1; mcnt < num_regs; mcnt++)
3810 best_regstart[mcnt] = regstart[mcnt];
3811 best_regend[mcnt] = regend[mcnt];
3817 /* If no failure points, don't restore garbage. And if
3818 last match is real best match, don't restore second
3820 else if (best_regs_set && !best_match_p)
3823 /* Restore best match. It may happen that `dend ==
3824 end_match_1' while the restored d is in string2.
3825 For example, the pattern `x.*y.*z' against the
3826 strings `x-' and `y-z-', if the two strings are
3827 not consecutive in memory. */
3828 DEBUG_PRINT1 ("Restoring best registers.\n");
3831 dend = ((d >= string1 && d <= end1)
3832 ? end_match_1 : end_match_2);
3834 for (mcnt = 1; mcnt < num_regs; mcnt++)
3836 regstart[mcnt] = best_regstart[mcnt];
3837 regend[mcnt] = best_regend[mcnt];
3840 } /* d != end_match_2 */
3843 DEBUG_PRINT1 ("Accepting match.\n");
3845 /* If caller wants register contents data back, do it. */
3846 if (regs && !bufp->no_sub)
3848 /* Have the register data arrays been allocated? */
3849 if (bufp->regs_allocated == REGS_UNALLOCATED)
3850 { /* No. So allocate them with malloc. We need one
3851 extra element beyond `num_regs' for the `-1' marker
3853 regs->num_regs = MAX (RE_NREGS, num_regs + 1);
3854 regs->start = TALLOC (regs->num_regs, regoff_t);
3855 regs->end = TALLOC (regs->num_regs, regoff_t);
3856 if (regs->start == NULL || regs->end == NULL)
3861 bufp->regs_allocated = REGS_REALLOCATE;
3863 else if (bufp->regs_allocated == REGS_REALLOCATE)
3864 { /* Yes. If we need more elements than were already
3865 allocated, reallocate them. If we need fewer, just
3867 if (regs->num_regs < num_regs + 1)
3869 regs->num_regs = num_regs + 1;
3870 RETALLOC (regs->start, regs->num_regs, regoff_t);
3871 RETALLOC (regs->end, regs->num_regs, regoff_t);
3872 if (regs->start == NULL || regs->end == NULL)
3881 /* These braces fend off a "empty body in an else-statement"
3882 warning under GCC when assert expands to nothing. */
3883 assert (bufp->regs_allocated == REGS_FIXED);
3886 /* Convert the pointer data in `regstart' and `regend' to
3887 indices. Register zero has to be set differently,
3888 since we haven't kept track of any info for it. */
3889 if (regs->num_regs > 0)
3891 regs->start[0] = pos;
3892 regs->end[0] = (MATCHING_IN_FIRST_STRING
3893 ? ((regoff_t) (d - string1))
3894 : ((regoff_t) (d - string2 + size1)));
3897 /* Go through the first `min (num_regs, regs->num_regs)'
3898 registers, since that is all we initialized. */
3899 for (mcnt = 1; mcnt < MIN (num_regs, regs->num_regs); mcnt++)
3901 if (REG_UNSET (regstart[mcnt]) || REG_UNSET (regend[mcnt]))
3902 regs->start[mcnt] = regs->end[mcnt] = -1;
3906 = (regoff_t) POINTER_TO_OFFSET (regstart[mcnt]);
3908 = (regoff_t) POINTER_TO_OFFSET (regend[mcnt]);
3912 /* If the regs structure we return has more elements than
3913 were in the pattern, set the extra elements to -1. If
3914 we (re)allocated the registers, this is the case,
3915 because we always allocate enough to have at least one
3917 for (mcnt = num_regs; mcnt < regs->num_regs; mcnt++)
3918 regs->start[mcnt] = regs->end[mcnt] = -1;
3919 } /* regs && !bufp->no_sub */
3921 DEBUG_PRINT4 ("%u failure points pushed, %u popped (%u remain).\n",
3922 nfailure_points_pushed, nfailure_points_popped,
3923 nfailure_points_pushed - nfailure_points_popped);
3924 DEBUG_PRINT2 ("%u registers pushed.\n", num_regs_pushed);
3926 mcnt = d - pos - (MATCHING_IN_FIRST_STRING
3930 DEBUG_PRINT2 ("Returning %d from re_match_2.\n", mcnt);
3936 /* Otherwise match next pattern command. */
3937 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
3939 /* Ignore these. Used to ignore the n of succeed_n's which
3940 currently have n == 0. */
3942 DEBUG_PRINT1 ("EXECUTING no_op.\n");
3946 DEBUG_PRINT1 ("EXECUTING succeed.\n");
3949 /* Match the next n pattern characters exactly. The following
3950 byte in the pattern defines n, and the n bytes after that
3951 are the characters to match. */
3954 DEBUG_PRINT2 ("EXECUTING exactn %d.\n", mcnt);
3956 /* This is written out as an if-else so we don't waste time
3957 testing `translate' inside the loop. */
3963 if ((unsigned char) translate[(unsigned char) *d++]
3964 != (unsigned char) *p++)
3974 if (*d++ != (char) *p++) goto fail;
3978 SET_REGS_MATCHED ();
3982 /* Match any character except possibly a newline or a null. */
3984 DEBUG_PRINT1 ("EXECUTING anychar.\n");
3988 if ((!(bufp->syntax & RE_DOT_NEWLINE) && TRANSLATE (*d) == '\n')
3989 || (bufp->syntax & RE_DOT_NOT_NULL && TRANSLATE (*d) == '\000'))
3992 SET_REGS_MATCHED ();
3993 DEBUG_PRINT2 (" Matched `%d'.\n", *d);
4001 register unsigned char c;
4002 boolean not = (re_opcode_t) *(p - 1) == charset_not;
4004 DEBUG_PRINT2 ("EXECUTING charset%s.\n", not ? "_not" : "");
4007 c = TRANSLATE (*d); /* The character to match. */
4009 /* Cast to `unsigned' instead of `unsigned char' in case the
4010 bit list is a full 32 bytes long. */
4011 if (c < (unsigned) (*p * BYTEWIDTH)
4012 && p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4017 if (!not) goto fail;
4019 SET_REGS_MATCHED ();
4025 /* The beginning of a group is represented by start_memory.
4026 The arguments are the register number in the next byte, and the
4027 number of groups inner to this one in the next. The text
4028 matched within the group is recorded (in the internal
4029 registers data structure) under the register number. */
4031 DEBUG_PRINT3 ("EXECUTING start_memory %d (%d):\n", *p, p[1]);
4033 /* Find out if this group can match the empty string. */
4034 p1 = p; /* To send to group_match_null_string_p. */
4036 if (REG_MATCH_NULL_STRING_P (reg_info[*p]) == MATCH_NULL_UNSET_VALUE)
4037 REG_MATCH_NULL_STRING_P (reg_info[*p])
4038 = group_match_null_string_p (&p1, pend, reg_info);
4040 /* Save the position in the string where we were the last time
4041 we were at this open-group operator in case the group is
4042 operated upon by a repetition operator, e.g., with `(a*)*b'
4043 against `ab'; then we want to ignore where we are now in
4044 the string in case this attempt to match fails. */
4045 old_regstart[*p] = REG_MATCH_NULL_STRING_P (reg_info[*p])
4046 ? REG_UNSET (regstart[*p]) ? d : regstart[*p]
4048 DEBUG_PRINT2 (" old_regstart: %d\n",
4049 POINTER_TO_OFFSET (old_regstart[*p]));
4052 DEBUG_PRINT2 (" regstart: %d\n", POINTER_TO_OFFSET (regstart[*p]));
4054 IS_ACTIVE (reg_info[*p]) = 1;
4055 MATCHED_SOMETHING (reg_info[*p]) = 0;
4057 /* Clear this whenever we change the register activity status. */
4058 set_regs_matched_done = 0;
4060 /* This is the new highest active register. */
4061 highest_active_reg = *p;
4063 /* If nothing was active before, this is the new lowest active
4065 if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
4066 lowest_active_reg = *p;
4068 /* Move past the register number and inner group count. */
4070 just_past_start_mem = p;
4075 /* The stop_memory opcode represents the end of a group. Its
4076 arguments are the same as start_memory's: the register
4077 number, and the number of inner groups. */
4079 DEBUG_PRINT3 ("EXECUTING stop_memory %d (%d):\n", *p, p[1]);
4081 /* We need to save the string position the last time we were at
4082 this close-group operator in case the group is operated
4083 upon by a repetition operator, e.g., with `((a*)*(b*)*)*'
4084 against `aba'; then we want to ignore where we are now in
4085 the string in case this attempt to match fails. */
4086 old_regend[*p] = REG_MATCH_NULL_STRING_P (reg_info[*p])
4087 ? REG_UNSET (regend[*p]) ? d : regend[*p]
4089 DEBUG_PRINT2 (" old_regend: %d\n",
4090 POINTER_TO_OFFSET (old_regend[*p]));
4093 DEBUG_PRINT2 (" regend: %d\n", POINTER_TO_OFFSET (regend[*p]));
4095 /* This register isn't active anymore. */
4096 IS_ACTIVE (reg_info[*p]) = 0;
4098 /* Clear this whenever we change the register activity status. */
4099 set_regs_matched_done = 0;
4101 /* If this was the only register active, nothing is active
4103 if (lowest_active_reg == highest_active_reg)
4105 lowest_active_reg = NO_LOWEST_ACTIVE_REG;
4106 highest_active_reg = NO_HIGHEST_ACTIVE_REG;
4109 { /* We must scan for the new highest active register, since
4110 it isn't necessarily one less than now: consider
4111 (a(b)c(d(e)f)g). When group 3 ends, after the f), the
4112 new highest active register is 1. */
4113 unsigned char r = *p - 1;
4114 while (r > 0 && !IS_ACTIVE (reg_info[r]))
4117 /* If we end up at register zero, that means that we saved
4118 the registers as the result of an `on_failure_jump', not
4119 a `start_memory', and we jumped to past the innermost
4120 `stop_memory'. For example, in ((.)*) we save
4121 registers 1 and 2 as a result of the *, but when we pop
4122 back to the second ), we are at the stop_memory 1.
4123 Thus, nothing is active. */
4126 lowest_active_reg = NO_LOWEST_ACTIVE_REG;
4127 highest_active_reg = NO_HIGHEST_ACTIVE_REG;
4130 highest_active_reg = r;
4133 /* If just failed to match something this time around with a
4134 group that's operated on by a repetition operator, try to
4135 force exit from the ``loop'', and restore the register
4136 information for this group that we had before trying this
4138 if ((!MATCHED_SOMETHING (reg_info[*p])
4139 || just_past_start_mem == p - 1)
4142 boolean is_a_jump_n = false;
4146 switch ((re_opcode_t) *p1++)
4150 case pop_failure_jump:
4151 case maybe_pop_jump:
4153 case dummy_failure_jump:
4154 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4164 /* If the next operation is a jump backwards in the pattern
4165 to an on_failure_jump right before the start_memory
4166 corresponding to this stop_memory, exit from the loop
4167 by forcing a failure after pushing on the stack the
4168 on_failure_jump's jump in the pattern, and d. */
4169 if (mcnt < 0 && (re_opcode_t) *p1 == on_failure_jump
4170 && (re_opcode_t) p1[3] == start_memory && p1[4] == *p)
4172 /* If this group ever matched anything, then restore
4173 what its registers were before trying this last
4174 failed match, e.g., with `(a*)*b' against `ab' for
4175 regstart[1], and, e.g., with `((a*)*(b*)*)*'
4176 against `aba' for regend[3].
4178 Also restore the registers for inner groups for,
4179 e.g., `((a*)(b*))*' against `aba' (register 3 would
4180 otherwise get trashed). */
4182 if (EVER_MATCHED_SOMETHING (reg_info[*p]))
4186 EVER_MATCHED_SOMETHING (reg_info[*p]) = 0;
4188 /* Restore this and inner groups' (if any) registers. */
4189 for (r = *p; r < *p + *(p + 1); r++)
4191 regstart[r] = old_regstart[r];
4193 /* xx why this test? */
4194 if (old_regend[r] >= regstart[r])
4195 regend[r] = old_regend[r];
4199 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4200 PUSH_FAILURE_POINT (p1 + mcnt, d, -2);
4206 /* Move past the register number and the inner group count. */
4211 /* \<digit> has been turned into a `duplicate' command which is
4212 followed by the numeric value of <digit> as the register number. */
4215 register const char *d2, *dend2;
4216 int regno = *p++; /* Get which register to match against. */
4217 DEBUG_PRINT2 ("EXECUTING duplicate %d.\n", regno);
4219 /* Can't back reference a group which we've never matched. */
4220 if (REG_UNSET (regstart[regno]) || REG_UNSET (regend[regno]))
4223 /* Where in input to try to start matching. */
4224 d2 = regstart[regno];
4226 /* Where to stop matching; if both the place to start and
4227 the place to stop matching are in the same string, then
4228 set to the place to stop, otherwise, for now have to use
4229 the end of the first string. */
4231 dend2 = ((FIRST_STRING_P (regstart[regno])
4232 == FIRST_STRING_P (regend[regno]))
4233 ? regend[regno] : end_match_1);
4236 /* If necessary, advance to next segment in register
4240 if (dend2 == end_match_2) break;
4241 if (dend2 == regend[regno]) break;
4243 /* End of string1 => advance to string2. */
4245 dend2 = regend[regno];
4247 /* At end of register contents => success */
4248 if (d2 == dend2) break;
4250 /* If necessary, advance to next segment in data. */
4253 /* How many characters left in this segment to match. */
4256 /* Want how many consecutive characters we can match in
4257 one shot, so, if necessary, adjust the count. */
4258 if (mcnt > dend2 - d2)
4261 /* Compare that many; failure if mismatch, else move
4264 ? bcmp_translate (d, d2, mcnt, translate)
4265 : bcmp (d, d2, mcnt))
4267 d += mcnt, d2 += mcnt;
4269 /* Do this because we've match some characters. */
4270 SET_REGS_MATCHED ();
4276 /* begline matches the empty string at the beginning of the string
4277 (unless `not_bol' is set in `bufp'), and, if
4278 `newline_anchor' is set, after newlines. */
4280 DEBUG_PRINT1 ("EXECUTING begline.\n");
4282 if (AT_STRINGS_BEG (d))
4284 if (!bufp->not_bol) break;
4286 else if (d[-1] == '\n' && bufp->newline_anchor)
4290 /* In all other cases, we fail. */
4294 /* endline is the dual of begline. */
4296 DEBUG_PRINT1 ("EXECUTING endline.\n");
4298 if (AT_STRINGS_END (d))
4300 if (!bufp->not_eol) break;
4303 /* We have to ``prefetch'' the next character. */
4304 else if ((d == end1 ? *string2 : *d) == '\n'
4305 && bufp->newline_anchor)
4312 /* Match at the very beginning of the data. */
4314 DEBUG_PRINT1 ("EXECUTING begbuf.\n");
4315 if (AT_STRINGS_BEG (d))
4320 /* Match at the very end of the data. */
4322 DEBUG_PRINT1 ("EXECUTING endbuf.\n");
4323 if (AT_STRINGS_END (d))
4328 /* on_failure_keep_string_jump is used to optimize `.*\n'. It
4329 pushes NULL as the value for the string on the stack. Then
4330 `pop_failure_point' will keep the current value for the
4331 string, instead of restoring it. To see why, consider
4332 matching `foo\nbar' against `.*\n'. The .* matches the foo;
4333 then the . fails against the \n. But the next thing we want
4334 to do is match the \n against the \n; if we restored the
4335 string value, we would be back at the foo.
4337 Because this is used only in specific cases, we don't need to
4338 check all the things that `on_failure_jump' does, to make
4339 sure the right things get saved on the stack. Hence we don't
4340 share its code. The only reason to push anything on the
4341 stack at all is that otherwise we would have to change
4342 `anychar's code to do something besides goto fail in this
4343 case; that seems worse than this. */
4344 case on_failure_keep_string_jump:
4345 DEBUG_PRINT1 ("EXECUTING on_failure_keep_string_jump");
4347 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4348 DEBUG_PRINT3 (" %d (to 0x%x):\n", mcnt, p + mcnt);
4350 PUSH_FAILURE_POINT (p + mcnt, NULL, -2);
4354 /* Uses of on_failure_jump:
4356 Each alternative starts with an on_failure_jump that points
4357 to the beginning of the next alternative. Each alternative
4358 except the last ends with a jump that in effect jumps past
4359 the rest of the alternatives. (They really jump to the
4360 ending jump of the following alternative, because tensioning
4361 these jumps is a hassle.)
4363 Repeats start with an on_failure_jump that points past both
4364 the repetition text and either the following jump or
4365 pop_failure_jump back to this on_failure_jump. */
4366 case on_failure_jump:
4368 DEBUG_PRINT1 ("EXECUTING on_failure_jump");
4370 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4371 DEBUG_PRINT3 (" %d (to 0x%x)", mcnt, p + mcnt);
4373 /* If this on_failure_jump comes right before a group (i.e.,
4374 the original * applied to a group), save the information
4375 for that group and all inner ones, so that if we fail back
4376 to this point, the group's information will be correct.
4377 For example, in \(a*\)*\1, we need the preceding group,
4378 and in \(zz\(a*\)b*\)\2, we need the inner group. */
4380 /* We can't use `p' to check ahead because we push
4381 a failure point to `p + mcnt' after we do this. */
4384 /* We need to skip no_op's before we look for the
4385 start_memory in case this on_failure_jump is happening as
4386 the result of a completed succeed_n, as in \(a\)\{1,3\}b\1
4388 while (p1 < pend && (re_opcode_t) *p1 == no_op)
4391 if (p1 < pend && (re_opcode_t) *p1 == start_memory)
4393 /* We have a new highest active register now. This will
4394 get reset at the start_memory we are about to get to,
4395 but we will have saved all the registers relevant to
4396 this repetition op, as described above. */
4397 highest_active_reg = *(p1 + 1) + *(p1 + 2);
4398 if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
4399 lowest_active_reg = *(p1 + 1);
4402 DEBUG_PRINT1 (":\n");
4403 PUSH_FAILURE_POINT (p + mcnt, d, -2);
4407 /* A smart repeat ends with `maybe_pop_jump'.
4408 We change it to either `pop_failure_jump' or `jump'. */
4409 case maybe_pop_jump:
4410 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4411 DEBUG_PRINT2 ("EXECUTING maybe_pop_jump %d.\n", mcnt);
4413 register unsigned char *p2 = p;
4415 /* Compare the beginning of the repeat with what in the
4416 pattern follows its end. If we can establish that there
4417 is nothing that they would both match, i.e., that we
4418 would have to backtrack because of (as in, e.g., `a*a')
4419 then we can change to pop_failure_jump, because we'll
4420 never have to backtrack.
4422 This is not true in the case of alternatives: in
4423 `(a|ab)*' we do need to backtrack to the `ab' alternative
4424 (e.g., if the string was `ab'). But instead of trying to
4425 detect that here, the alternative has put on a dummy
4426 failure point which is what we will end up popping. */
4428 /* Skip over open/close-group commands.
4429 If what follows this loop is a ...+ construct,
4430 look at what begins its body, since we will have to
4431 match at least one of that. */
4435 && ((re_opcode_t) *p2 == stop_memory
4436 || (re_opcode_t) *p2 == start_memory))
4438 else if (p2 + 6 < pend
4439 && (re_opcode_t) *p2 == dummy_failure_jump)
4446 /* p1[0] ... p1[2] are the `on_failure_jump' corresponding
4447 to the `maybe_finalize_jump' of this case. Examine what
4450 /* If we're at the end of the pattern, we can change. */
4453 /* Consider what happens when matching ":\(.*\)"
4454 against ":/". I don't really understand this code
4456 p[-3] = (unsigned char) pop_failure_jump;
4458 (" End of pattern: change to `pop_failure_jump'.\n");
4461 else if ((re_opcode_t) *p2 == exactn
4462 || (bufp->newline_anchor && (re_opcode_t) *p2 == endline))
4464 register unsigned char c
4465 = *p2 == (unsigned char) endline ? '\n' : p2[2];
4467 if ((re_opcode_t) p1[3] == exactn && p1[5] != c)
4469 p[-3] = (unsigned char) pop_failure_jump;
4470 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n",
4474 else if ((re_opcode_t) p1[3] == charset
4475 || (re_opcode_t) p1[3] == charset_not)
4477 int not = (re_opcode_t) p1[3] == charset_not;
4479 if (c < (unsigned char) (p1[4] * BYTEWIDTH)
4480 && p1[5 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4483 /* `not' is equal to 1 if c would match, which means
4484 that we can't change to pop_failure_jump. */
4487 p[-3] = (unsigned char) pop_failure_jump;
4488 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4492 else if ((re_opcode_t) *p2 == charset)
4495 register unsigned char c
4496 = *p2 == (unsigned char) endline ? '\n' : p2[2];
4499 if ((re_opcode_t) p1[3] == exactn
4500 && ! ((int) p2[1] * BYTEWIDTH > (int) p1[4]
4501 && (p2[1 + p1[4] / BYTEWIDTH]
4502 & (1 << (p1[4] % BYTEWIDTH)))))
4504 p[-3] = (unsigned char) pop_failure_jump;
4505 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n",
4509 else if ((re_opcode_t) p1[3] == charset_not)
4512 /* We win if the charset_not inside the loop
4513 lists every character listed in the charset after. */
4514 for (idx = 0; idx < (int) p2[1]; idx++)
4515 if (! (p2[2 + idx] == 0
4516 || (idx < (int) p1[4]
4517 && ((p2[2 + idx] & ~ p1[5 + idx]) == 0))))
4522 p[-3] = (unsigned char) pop_failure_jump;
4523 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4526 else if ((re_opcode_t) p1[3] == charset)
4529 /* We win if the charset inside the loop
4530 has no overlap with the one after the loop. */
4532 idx < (int) p2[1] && idx < (int) p1[4];
4534 if ((p2[2 + idx] & p1[5 + idx]) != 0)
4537 if (idx == p2[1] || idx == p1[4])
4539 p[-3] = (unsigned char) pop_failure_jump;
4540 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4545 p -= 2; /* Point at relative address again. */
4546 if ((re_opcode_t) p[-1] != pop_failure_jump)
4548 p[-1] = (unsigned char) jump;
4549 DEBUG_PRINT1 (" Match => jump.\n");
4550 goto unconditional_jump;
4552 /* Note fall through. */
4555 /* The end of a simple repeat has a pop_failure_jump back to
4556 its matching on_failure_jump, where the latter will push a
4557 failure point. The pop_failure_jump takes off failure
4558 points put on by this pop_failure_jump's matching
4559 on_failure_jump; we got through the pattern to here from the
4560 matching on_failure_jump, so didn't fail. */
4561 case pop_failure_jump:
4563 /* We need to pass separate storage for the lowest and
4564 highest registers, even though we don't care about the
4565 actual values. Otherwise, we will restore only one
4566 register from the stack, since lowest will == highest in
4567 `pop_failure_point'. */
4568 unsigned dummy_low_reg, dummy_high_reg;
4569 unsigned char *pdummy;
4572 DEBUG_PRINT1 ("EXECUTING pop_failure_jump.\n");
4573 POP_FAILURE_POINT (sdummy, pdummy,
4574 dummy_low_reg, dummy_high_reg,
4575 reg_dummy, reg_dummy, reg_info_dummy);
4577 /* Note fall through. */
4580 /* Unconditionally jump (without popping any failure points). */
4583 EXTRACT_NUMBER_AND_INCR (mcnt, p); /* Get the amount to jump. */
4584 DEBUG_PRINT2 ("EXECUTING jump %d ", mcnt);
4585 p += mcnt; /* Do the jump. */
4586 DEBUG_PRINT2 ("(to 0x%x).\n", p);
4590 /* We need this opcode so we can detect where alternatives end
4591 in `group_match_null_string_p' et al. */
4593 DEBUG_PRINT1 ("EXECUTING jump_past_alt.\n");
4594 goto unconditional_jump;
4597 /* Normally, the on_failure_jump pushes a failure point, which
4598 then gets popped at pop_failure_jump. We will end up at
4599 pop_failure_jump, also, and with a pattern of, say, `a+', we
4600 are skipping over the on_failure_jump, so we have to push
4601 something meaningless for pop_failure_jump to pop. */
4602 case dummy_failure_jump:
4603 DEBUG_PRINT1 ("EXECUTING dummy_failure_jump.\n");
4604 /* It doesn't matter what we push for the string here. What
4605 the code at `fail' tests is the value for the pattern. */
4606 PUSH_FAILURE_POINT (0, 0, -2);
4607 goto unconditional_jump;
4610 /* At the end of an alternative, we need to push a dummy failure
4611 point in case we are followed by a `pop_failure_jump', because
4612 we don't want the failure point for the alternative to be
4613 popped. For example, matching `(a|ab)*' against `aab'
4614 requires that we match the `ab' alternative. */
4615 case push_dummy_failure:
4616 DEBUG_PRINT1 ("EXECUTING push_dummy_failure.\n");
4617 /* See comments just above at `dummy_failure_jump' about the
4619 PUSH_FAILURE_POINT (0, 0, -2);
4622 /* Have to succeed matching what follows at least n times.
4623 After that, handle like `on_failure_jump'. */
4625 EXTRACT_NUMBER (mcnt, p + 2);
4626 DEBUG_PRINT2 ("EXECUTING succeed_n %d.\n", mcnt);
4629 /* Originally, this is how many times we HAVE to succeed. */
4634 STORE_NUMBER_AND_INCR (p, mcnt);
4635 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p, mcnt);
4639 DEBUG_PRINT2 (" Setting two bytes from 0x%x to no_op.\n", p+2);
4640 p[2] = (unsigned char) no_op;
4641 p[3] = (unsigned char) no_op;
4647 EXTRACT_NUMBER (mcnt, p + 2);
4648 DEBUG_PRINT2 ("EXECUTING jump_n %d.\n", mcnt);
4650 /* Originally, this is how many times we CAN jump. */
4654 STORE_NUMBER (p + 2, mcnt);
4655 goto unconditional_jump;
4657 /* If don't have to jump any more, skip over the rest of command. */
4664 DEBUG_PRINT1 ("EXECUTING set_number_at.\n");
4666 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4668 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4669 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p1, mcnt);
4670 STORE_NUMBER (p1, mcnt);
4675 DEBUG_PRINT1 ("EXECUTING wordbound.\n");
4676 if (AT_WORD_BOUNDARY (d))
4681 DEBUG_PRINT1 ("EXECUTING notwordbound.\n");
4682 if (AT_WORD_BOUNDARY (d))
4687 DEBUG_PRINT1 ("EXECUTING wordbeg.\n");
4688 if (WORDCHAR_P (d) && (AT_STRINGS_BEG (d) || !WORDCHAR_P (d - 1)))
4693 DEBUG_PRINT1 ("EXECUTING wordend.\n");
4694 if (!AT_STRINGS_BEG (d) && WORDCHAR_P (d - 1)
4695 && (!WORDCHAR_P (d) || AT_STRINGS_END (d)))
4701 DEBUG_PRINT1 ("EXECUTING before_dot.\n");
4702 if (PTR_CHAR_POS ((unsigned char *) d) >= point)
4707 DEBUG_PRINT1 ("EXECUTING at_dot.\n");
4708 if (PTR_CHAR_POS ((unsigned char *) d) != point)
4713 DEBUG_PRINT1 ("EXECUTING after_dot.\n");
4714 if (PTR_CHAR_POS ((unsigned char *) d) <= point)
4719 DEBUG_PRINT2 ("EXECUTING syntaxspec %d.\n", mcnt);
4724 DEBUG_PRINT1 ("EXECUTING Emacs wordchar.\n");
4728 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
4730 if (SYNTAX (d[-1]) != (enum syntaxcode) mcnt)
4732 SET_REGS_MATCHED ();
4736 DEBUG_PRINT2 ("EXECUTING notsyntaxspec %d.\n", mcnt);
4738 goto matchnotsyntax;
4741 DEBUG_PRINT1 ("EXECUTING Emacs notwordchar.\n");
4745 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
4747 if (SYNTAX (d[-1]) == (enum syntaxcode) mcnt)
4749 SET_REGS_MATCHED ();
4752 #else /* not emacs */
4754 DEBUG_PRINT1 ("EXECUTING non-Emacs wordchar.\n");
4756 if (!WORDCHAR_P (d))
4758 SET_REGS_MATCHED ();
4763 DEBUG_PRINT1 ("EXECUTING non-Emacs notwordchar.\n");
4767 SET_REGS_MATCHED ();
4770 #endif /* not emacs */
4775 continue; /* Successfully executed one pattern command; keep going. */
4778 /* We goto here if a matching operation fails. */
4780 if (!FAIL_STACK_EMPTY ())
4781 { /* A restart point is known. Restore to that state. */
4782 DEBUG_PRINT1 ("\nFAIL:\n");
4783 POP_FAILURE_POINT (d, p,
4784 lowest_active_reg, highest_active_reg,
4785 regstart, regend, reg_info);
4787 /* If this failure point is a dummy, try the next one. */
4791 /* If we failed to the end of the pattern, don't examine *p. */
4795 boolean is_a_jump_n = false;
4797 /* If failed to a backwards jump that's part of a repetition
4798 loop, need to pop this failure point and use the next one. */
4799 switch ((re_opcode_t) *p)
4803 case maybe_pop_jump:
4804 case pop_failure_jump:
4807 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4810 if ((is_a_jump_n && (re_opcode_t) *p1 == succeed_n)
4812 && (re_opcode_t) *p1 == on_failure_jump))
4820 if (d >= string1 && d <= end1)
4824 break; /* Matching at this starting point really fails. */
4828 goto restore_best_regs;
4832 return -1; /* Failure to match. */
4835 /* Subroutine definitions for re_match_2. */
4838 /* We are passed P pointing to a register number after a start_memory.
4840 Return true if the pattern up to the corresponding stop_memory can
4841 match the empty string, and false otherwise.
4843 If we find the matching stop_memory, sets P to point to one past its number.
4844 Otherwise, sets P to an undefined byte less than or equal to END.
4846 We don't handle duplicates properly (yet). */
4849 group_match_null_string_p (p, end, reg_info)
4850 unsigned char **p, *end;
4851 register_info_type *reg_info;
4854 /* Point to after the args to the start_memory. */
4855 unsigned char *p1 = *p + 2;
4859 /* Skip over opcodes that can match nothing, and return true or
4860 false, as appropriate, when we get to one that can't, or to the
4861 matching stop_memory. */
4863 switch ((re_opcode_t) *p1)
4865 /* Could be either a loop or a series of alternatives. */
4866 case on_failure_jump:
4868 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4870 /* If the next operation is not a jump backwards in the
4875 /* Go through the on_failure_jumps of the alternatives,
4876 seeing if any of the alternatives cannot match nothing.
4877 The last alternative starts with only a jump,
4878 whereas the rest start with on_failure_jump and end
4879 with a jump, e.g., here is the pattern for `a|b|c':
4881 /on_failure_jump/0/6/exactn/1/a/jump_past_alt/0/6
4882 /on_failure_jump/0/6/exactn/1/b/jump_past_alt/0/3
4885 So, we have to first go through the first (n-1)
4886 alternatives and then deal with the last one separately. */
4889 /* Deal with the first (n-1) alternatives, which start
4890 with an on_failure_jump (see above) that jumps to right
4891 past a jump_past_alt. */
4893 while ((re_opcode_t) p1[mcnt-3] == jump_past_alt)
4895 /* `mcnt' holds how many bytes long the alternative
4896 is, including the ending `jump_past_alt' and
4899 if (!alt_match_null_string_p (p1, p1 + mcnt - 3,
4903 /* Move to right after this alternative, including the
4907 /* Break if it's the beginning of an n-th alternative
4908 that doesn't begin with an on_failure_jump. */
4909 if ((re_opcode_t) *p1 != on_failure_jump)
4912 /* Still have to check that it's not an n-th
4913 alternative that starts with an on_failure_jump. */
4915 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4916 if ((re_opcode_t) p1[mcnt-3] != jump_past_alt)
4918 /* Get to the beginning of the n-th alternative. */
4924 /* Deal with the last alternative: go back and get number
4925 of the `jump_past_alt' just before it. `mcnt' contains
4926 the length of the alternative. */
4927 EXTRACT_NUMBER (mcnt, p1 - 2);
4929 if (!alt_match_null_string_p (p1, p1 + mcnt, reg_info))
4932 p1 += mcnt; /* Get past the n-th alternative. */
4938 assert (p1[1] == **p);
4944 if (!common_op_match_null_string_p (&p1, end, reg_info))
4947 } /* while p1 < end */
4950 } /* group_match_null_string_p */
4953 /* Similar to group_match_null_string_p, but doesn't deal with alternatives:
4954 It expects P to be the first byte of a single alternative and END one
4955 byte past the last. The alternative can contain groups. */
4958 alt_match_null_string_p (p, end, reg_info)
4959 unsigned char *p, *end;
4960 register_info_type *reg_info;
4963 unsigned char *p1 = p;
4967 /* Skip over opcodes that can match nothing, and break when we get
4968 to one that can't. */
4970 switch ((re_opcode_t) *p1)
4973 case on_failure_jump:
4975 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4980 if (!common_op_match_null_string_p (&p1, end, reg_info))
4983 } /* while p1 < end */
4986 } /* alt_match_null_string_p */
4989 /* Deals with the ops common to group_match_null_string_p and
4990 alt_match_null_string_p.
4992 Sets P to one after the op and its arguments, if any. */
4995 common_op_match_null_string_p (p, end, reg_info)
4996 unsigned char **p, *end;
4997 register_info_type *reg_info;
5002 unsigned char *p1 = *p;
5004 switch ((re_opcode_t) *p1++)
5024 assert (reg_no > 0 && reg_no <= MAX_REGNUM);
5025 ret = group_match_null_string_p (&p1, end, reg_info);
5027 /* Have to set this here in case we're checking a group which
5028 contains a group and a back reference to it. */
5030 if (REG_MATCH_NULL_STRING_P (reg_info[reg_no]) == MATCH_NULL_UNSET_VALUE)
5031 REG_MATCH_NULL_STRING_P (reg_info[reg_no]) = ret;
5037 /* If this is an optimized succeed_n for zero times, make the jump. */
5039 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5047 /* Get to the number of times to succeed. */
5049 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5054 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5062 if (!REG_MATCH_NULL_STRING_P (reg_info[*p1]))
5070 /* All other opcodes mean we cannot match the empty string. */
5076 } /* common_op_match_null_string_p */
5079 /* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
5080 bytes; nonzero otherwise. */
5083 bcmp_translate (s1, s2, len, translate)
5084 unsigned char *s1, *s2;
5086 RE_TRANSLATE_TYPE translate;
5088 register unsigned char *p1 = s1, *p2 = s2;
5091 if (translate[*p1++] != translate[*p2++]) return 1;
5097 /* Entry points for GNU code. */
5099 /* re_compile_pattern is the GNU regular expression compiler: it
5100 compiles PATTERN (of length SIZE) and puts the result in BUFP.
5101 Returns 0 if the pattern was valid, otherwise an error string.
5103 Assumes the `allocated' (and perhaps `buffer') and `translate' fields
5104 are set in BUFP on entry.
5106 We call regex_compile to do the actual compilation. */
5109 re_compile_pattern (pattern, length, bufp)
5110 const char *pattern;
5112 struct re_pattern_buffer *bufp;
5116 /* GNU code is written to assume at least RE_NREGS registers will be set
5117 (and at least one extra will be -1). */
5118 bufp->regs_allocated = REGS_UNALLOCATED;
5120 /* And GNU code determines whether or not to get register information
5121 by passing null for the REGS argument to re_match, etc., not by
5125 /* Match anchors at newline. */
5126 bufp->newline_anchor = 1;
5128 ret = regex_compile (pattern, length, re_syntax_options, bufp);
5132 return gettext (re_error_msgid[(int) ret]);
5135 /* Entry points compatible with 4.2 BSD regex library. We don't define
5136 them unless specifically requested. */
5138 #ifdef _REGEX_RE_COMP
5140 /* BSD has one and only one pattern buffer. */
5141 static struct re_pattern_buffer re_comp_buf;
5151 if (!re_comp_buf.buffer)
5152 return gettext ("No previous regular expression");
5156 if (!re_comp_buf.buffer)
5158 re_comp_buf.buffer = (unsigned char *) malloc (200);
5159 if (re_comp_buf.buffer == NULL)
5160 return gettext (re_error_msgid[(int) REG_ESPACE]);
5161 re_comp_buf.allocated = 200;
5163 re_comp_buf.fastmap = (char *) malloc (1 << BYTEWIDTH);
5164 if (re_comp_buf.fastmap == NULL)
5165 return gettext (re_error_msgid[(int) REG_ESPACE]);
5168 /* Since `re_exec' always passes NULL for the `regs' argument, we
5169 don't need to initialize the pattern buffer fields which affect it. */
5171 /* Match anchors at newlines. */
5172 re_comp_buf.newline_anchor = 1;
5174 ret = regex_compile (s, strlen (s), re_syntax_options, &re_comp_buf);
5179 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
5180 return (char *) gettext (re_error_msgid[(int) ret]);
5188 const int len = strlen (s);
5190 0 <= re_search (&re_comp_buf, s, len, 0, len, (struct re_registers *) 0);
5192 #endif /* _REGEX_RE_COMP */
5194 /* POSIX.2 functions. Don't define these for Emacs. */
5198 /* regcomp takes a regular expression as a string and compiles it.
5200 PREG is a regex_t *. We do not expect any fields to be initialized,
5201 since POSIX says we shouldn't. Thus, we set
5203 `buffer' to the compiled pattern;
5204 `used' to the length of the compiled pattern;
5205 `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
5206 REG_EXTENDED bit in CFLAGS is set; otherwise, to
5207 RE_SYNTAX_POSIX_BASIC;
5208 `newline_anchor' to REG_NEWLINE being set in CFLAGS;
5209 `fastmap' and `fastmap_accurate' to zero;
5210 `re_nsub' to the number of subexpressions in PATTERN.
5212 PATTERN is the address of the pattern string.
5214 CFLAGS is a series of bits which affect compilation.
5216 If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
5217 use POSIX basic syntax.
5219 If REG_NEWLINE is set, then . and [^...] don't match newline.
5220 Also, regexec will try a match beginning after every newline.
5222 If REG_ICASE is set, then we considers upper- and lowercase
5223 versions of letters to be equivalent when matching.
5225 If REG_NOSUB is set, then when PREG is passed to regexec, that
5226 routine will report only success or failure, and nothing about the
5229 It returns 0 if it succeeds, nonzero if it doesn't. (See regex.h for
5230 the return codes and their meanings.) */
5233 regcomp (preg, pattern, cflags)
5235 const char *pattern;
5240 = (cflags & REG_EXTENDED) ?
5241 RE_SYNTAX_POSIX_EXTENDED : RE_SYNTAX_POSIX_BASIC;
5243 /* regex_compile will allocate the space for the compiled pattern. */
5245 preg->allocated = 0;
5248 /* Don't bother to use a fastmap when searching. This simplifies the
5249 REG_NEWLINE case: if we used a fastmap, we'd have to put all the
5250 characters after newlines into the fastmap. This way, we just try
5254 if (cflags & REG_ICASE)
5259 = (RE_TRANSLATE_TYPE) malloc (CHAR_SET_SIZE
5260 * sizeof (*(RE_TRANSLATE_TYPE)0));
5261 if (preg->translate == NULL)
5262 return (int) REG_ESPACE;
5264 /* Map uppercase characters to corresponding lowercase ones. */
5265 for (i = 0; i < CHAR_SET_SIZE; i++)
5266 preg->translate[i] = ISUPPER (i) ? tolower (i) : i;
5269 preg->translate = NULL;
5271 /* If REG_NEWLINE is set, newlines are treated differently. */
5272 if (cflags & REG_NEWLINE)
5273 { /* REG_NEWLINE implies neither . nor [^...] match newline. */
5274 syntax &= ~RE_DOT_NEWLINE;
5275 syntax |= RE_HAT_LISTS_NOT_NEWLINE;
5276 /* It also changes the matching behavior. */
5277 preg->newline_anchor = 1;
5280 preg->newline_anchor = 0;
5282 preg->no_sub = !!(cflags & REG_NOSUB);
5284 /* POSIX says a null character in the pattern terminates it, so we
5285 can use strlen here in compiling the pattern. */
5286 ret = regex_compile (pattern, strlen (pattern), syntax, preg);
5288 /* POSIX doesn't distinguish between an unmatched open-group and an
5289 unmatched close-group: both are REG_EPAREN. */
5290 if (ret == REG_ERPAREN) ret = REG_EPAREN;
5296 /* regexec searches for a given pattern, specified by PREG, in the
5299 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
5300 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
5301 least NMATCH elements, and we set them to the offsets of the
5302 corresponding matched substrings.
5304 EFLAGS specifies `execution flags' which affect matching: if
5305 REG_NOTBOL is set, then ^ does not match at the beginning of the
5306 string; if REG_NOTEOL is set, then $ does not match at the end.
5308 We return 0 if we find a match and REG_NOMATCH if not. */
5311 regexec (preg, string, nmatch, pmatch, eflags)
5312 const regex_t *preg;
5315 regmatch_t pmatch[];
5319 struct re_registers regs;
5320 regex_t private_preg;
5321 int len = strlen (string);
5322 boolean want_reg_info = !preg->no_sub && nmatch > 0;
5324 private_preg = *preg;
5326 private_preg.not_bol = !!(eflags & REG_NOTBOL);
5327 private_preg.not_eol = !!(eflags & REG_NOTEOL);
5329 /* The user has told us exactly how many registers to return
5330 information about, via `nmatch'. We have to pass that on to the
5331 matching routines. */
5332 private_preg.regs_allocated = REGS_FIXED;
5336 regs.num_regs = nmatch;
5337 regs.start = TALLOC (nmatch, regoff_t);
5338 regs.end = TALLOC (nmatch, regoff_t);
5339 if (regs.start == NULL || regs.end == NULL)
5340 return (int) REG_NOMATCH;
5343 /* Perform the searching operation. */
5344 ret = re_search (&private_preg, string, len,
5345 /* start: */ 0, /* range: */ len,
5346 want_reg_info ? ®s : (struct re_registers *) 0);
5348 /* Copy the register information to the POSIX structure. */
5355 for (r = 0; r < nmatch; r++)
5357 pmatch[r].rm_so = regs.start[r];
5358 pmatch[r].rm_eo = regs.end[r];
5362 /* If we needed the temporary register info, free the space now. */
5367 /* We want zero return to mean success, unlike `re_search'. */
5368 return ret >= 0 ? (int) REG_NOERROR : (int) REG_NOMATCH;
5372 /* Returns a message corresponding to an error code, ERRCODE, returned
5373 from either regcomp or regexec. We don't use PREG here. */
5376 regerror (errcode, preg, errbuf, errbuf_size)
5378 const regex_t *preg;
5386 || errcode >= (sizeof (re_error_msgid) / sizeof (re_error_msgid[0])))
5387 /* Only error codes returned by the rest of the code should be passed
5388 to this routine. If we are given anything else, or if other regex
5389 code generates an invalid error code, then the program has a bug.
5390 Dump core so we can fix it. */
5393 msg = gettext (re_error_msgid[errcode]);
5395 msg_size = strlen (msg) + 1; /* Includes the null. */
5397 if (errbuf_size != 0)
5399 if (msg_size > errbuf_size)
5401 strncpy (errbuf, msg, errbuf_size - 1);
5402 errbuf[errbuf_size - 1] = 0;
5405 strcpy (errbuf, msg);
5412 /* Free dynamically allocated space used by PREG. */
5418 if (preg->buffer != NULL)
5419 free (preg->buffer);
5420 preg->buffer = NULL;
5422 preg->allocated = 0;
5425 if (preg->fastmap != NULL)
5426 free (preg->fastmap);
5427 preg->fastmap = NULL;
5428 preg->fastmap_accurate = 0;
5430 if (preg->translate != NULL)
5431 free (preg->translate);
5432 preg->translate = NULL;
5435 #endif /* not emacs */
5439 make-backup-files: t
5441 trim-versions-without-asking: nil