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 HAVE_STRING_H || 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. */
242 #endif /* not _AIX */
243 #endif /* not HAVE_ALLOCA_H */
244 #endif /* not __GNUC__ */
246 #endif /* not alloca */
248 #define REGEX_ALLOCATE alloca
250 /* Assumes a `char *destination' variable. */
251 #define REGEX_REALLOCATE(source, osize, nsize) \
252 (destination = (char *) alloca (nsize), \
253 bcopy (source, destination, osize), \
256 /* No need to do anything to free, after alloca. */
257 #define REGEX_FREE(arg) ((void)0) /* Do nothing! But inhibit gcc warning. */
259 #endif /* not REGEX_MALLOC */
261 /* Define how to allocate the failure stack. */
264 #define REGEX_ALLOCATE_STACK(size) \
265 r_alloc (&failure_stack_ptr, (size))
266 #define REGEX_REALLOCATE_STACK(source, osize, nsize) \
267 r_re_alloc (&failure_stack_ptr, (nsize))
268 #define REGEX_FREE_STACK(ptr) \
269 r_alloc_free (&failure_stack_ptr)
271 #else /* not REL_ALLOC */
275 #define REGEX_ALLOCATE_STACK malloc
276 #define REGEX_REALLOCATE_STACK(source, osize, nsize) realloc (source, nsize)
277 #define REGEX_FREE_STACK free
279 #else /* not REGEX_MALLOC */
281 #define REGEX_ALLOCATE_STACK alloca
283 #define REGEX_REALLOCATE_STACK(source, osize, nsize) \
284 REGEX_REALLOCATE (source, osize, nsize)
285 /* No need to explicitly free anything. */
286 #define REGEX_FREE_STACK(arg)
288 #endif /* not REGEX_MALLOC */
289 #endif /* not REL_ALLOC */
292 /* True if `size1' is non-NULL and PTR is pointing anywhere inside
293 `string1' or just past its end. This works if PTR is NULL, which is
295 #define FIRST_STRING_P(ptr) \
296 (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
298 /* (Re)Allocate N items of type T using malloc, or fail. */
299 #define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
300 #define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
301 #define RETALLOC_IF(addr, n, t) \
302 if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
303 #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
305 #define BYTEWIDTH 8 /* In bits. */
307 #define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
311 #define MAX(a, b) ((a) > (b) ? (a) : (b))
312 #define MIN(a, b) ((a) < (b) ? (a) : (b))
314 typedef char boolean;
318 static int re_match_2_internal ();
320 /* These are the command codes that appear in compiled regular
321 expressions. Some opcodes are followed by argument bytes. A
322 command code can specify any interpretation whatsoever for its
323 arguments. Zero bytes may appear in the compiled regular expression. */
329 /* Succeed right away--no more backtracking. */
332 /* Followed by one byte giving n, then by n literal bytes. */
335 /* Matches any (more or less) character. */
338 /* Matches any one char belonging to specified set. First
339 following byte is number of bitmap bytes. Then come bytes
340 for a bitmap saying which chars are in. Bits in each byte
341 are ordered low-bit-first. A character is in the set if its
342 bit is 1. A character too large to have a bit in the map is
343 automatically not in the set. */
346 /* Same parameters as charset, but match any character that is
347 not one of those specified. */
350 /* Start remembering the text that is matched, for storing in a
351 register. Followed by one byte with the register number, in
352 the range 0 to one less than the pattern buffer's re_nsub
353 field. Then followed by one byte with the number of groups
354 inner to this one. (This last has to be part of the
355 start_memory only because we need it in the on_failure_jump
359 /* Stop remembering the text that is matched and store it in a
360 memory register. Followed by one byte with the register
361 number, in the range 0 to one less than `re_nsub' in the
362 pattern buffer, and one byte with the number of inner groups,
363 just like `start_memory'. (We need the number of inner
364 groups here because we don't have any easy way of finding the
365 corresponding start_memory when we're at a stop_memory.) */
368 /* Match a duplicate of something remembered. Followed by one
369 byte containing the register number. */
372 /* Fail unless at beginning of line. */
375 /* Fail unless at end of line. */
378 /* Succeeds if at beginning of buffer (if emacs) or at beginning
379 of string to be matched (if not). */
382 /* Analogously, for end of buffer/string. */
385 /* Followed by two byte relative address to which to jump. */
388 /* Same as jump, but marks the end of an alternative. */
391 /* Followed by two-byte relative address of place to resume at
392 in case of failure. */
395 /* Like on_failure_jump, but pushes a placeholder instead of the
396 current string position when executed. */
397 on_failure_keep_string_jump,
399 /* Throw away latest failure point and then jump to following
400 two-byte relative address. */
403 /* Change to pop_failure_jump if know won't have to backtrack to
404 match; otherwise change to jump. This is used to jump
405 back to the beginning of a repeat. If what follows this jump
406 clearly won't match what the repeat does, such that we can be
407 sure that there is no use backtracking out of repetitions
408 already matched, then we change it to a pop_failure_jump.
409 Followed by two-byte address. */
412 /* Jump to following two-byte address, and push a dummy failure
413 point. This failure point will be thrown away if an attempt
414 is made to use it for a failure. A `+' construct makes this
415 before the first repeat. Also used as an intermediary kind
416 of jump when compiling an alternative. */
419 /* Push a dummy failure point and continue. Used at the end of
423 /* Followed by two-byte relative address and two-byte number n.
424 After matching N times, jump to the address upon failure. */
427 /* Followed by two-byte relative address, and two-byte number n.
428 Jump to the address N times, then fail. */
431 /* Set the following two-byte relative address to the
432 subsequent two-byte number. The address *includes* the two
436 wordchar, /* Matches any word-constituent character. */
437 notwordchar, /* Matches any char that is not a word-constituent. */
439 wordbeg, /* Succeeds if at word beginning. */
440 wordend, /* Succeeds if at word end. */
442 wordbound, /* Succeeds if at a word boundary. */
443 notwordbound /* Succeeds if not at a word boundary. */
446 ,before_dot, /* Succeeds if before point. */
447 at_dot, /* Succeeds if at point. */
448 after_dot, /* Succeeds if after point. */
450 /* Matches any character whose syntax is specified. Followed by
451 a byte which contains a syntax code, e.g., Sword. */
454 /* Matches any character whose syntax is not that specified. */
459 /* Common operations on the compiled pattern. */
461 /* Store NUMBER in two contiguous bytes starting at DESTINATION. */
463 #define STORE_NUMBER(destination, number) \
465 (destination)[0] = (number) & 0377; \
466 (destination)[1] = (number) >> 8; \
469 /* Same as STORE_NUMBER, except increment DESTINATION to
470 the byte after where the number is stored. Therefore, DESTINATION
471 must be an lvalue. */
473 #define STORE_NUMBER_AND_INCR(destination, number) \
475 STORE_NUMBER (destination, number); \
476 (destination) += 2; \
479 /* Put into DESTINATION a number stored in two contiguous bytes starting
482 #define EXTRACT_NUMBER(destination, source) \
484 (destination) = *(source) & 0377; \
485 (destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8; \
490 extract_number (dest, source)
492 unsigned char *source;
494 int temp = SIGN_EXTEND_CHAR (*(source + 1));
495 *dest = *source & 0377;
499 #ifndef EXTRACT_MACROS /* To debug the macros. */
500 #undef EXTRACT_NUMBER
501 #define EXTRACT_NUMBER(dest, src) extract_number (&dest, src)
502 #endif /* not EXTRACT_MACROS */
506 /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
507 SOURCE must be an lvalue. */
509 #define EXTRACT_NUMBER_AND_INCR(destination, source) \
511 EXTRACT_NUMBER (destination, source); \
517 extract_number_and_incr (destination, source)
519 unsigned char **source;
521 extract_number (destination, *source);
525 #ifndef EXTRACT_MACROS
526 #undef EXTRACT_NUMBER_AND_INCR
527 #define EXTRACT_NUMBER_AND_INCR(dest, src) \
528 extract_number_and_incr (&dest, &src)
529 #endif /* not EXTRACT_MACROS */
533 /* If DEBUG is defined, Regex prints many voluminous messages about what
534 it is doing (if the variable `debug' is nonzero). If linked with the
535 main program in `iregex.c', you can enter patterns and strings
536 interactively. And if linked with the main program in `main.c' and
537 the other test files, you can run the already-written tests. */
541 /* We use standard I/O for debugging. */
544 /* It is useful to test things that ``must'' be true when debugging. */
547 static int debug = 0;
549 #define DEBUG_STATEMENT(e) e
550 #define DEBUG_PRINT1(x) if (debug) printf (x)
551 #define DEBUG_PRINT2(x1, x2) if (debug) printf (x1, x2)
552 #define DEBUG_PRINT3(x1, x2, x3) if (debug) printf (x1, x2, x3)
553 #define DEBUG_PRINT4(x1, x2, x3, x4) if (debug) printf (x1, x2, x3, x4)
554 #define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) \
555 if (debug) print_partial_compiled_pattern (s, e)
556 #define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) \
557 if (debug) print_double_string (w, s1, sz1, s2, sz2)
560 /* Print the fastmap in human-readable form. */
563 print_fastmap (fastmap)
566 unsigned was_a_range = 0;
569 while (i < (1 << BYTEWIDTH))
575 while (i < (1 << BYTEWIDTH) && fastmap[i])
591 /* Print a compiled pattern string in human-readable form, starting at
592 the START pointer into it and ending just before the pointer END. */
595 print_partial_compiled_pattern (start, end)
596 unsigned char *start;
600 unsigned char *p = start;
601 unsigned char *pend = end;
609 /* Loop over pattern commands. */
612 printf ("%d:\t", p - start);
614 switch ((re_opcode_t) *p++)
622 printf ("/exactn/%d", mcnt);
633 printf ("/start_memory/%d/%d", mcnt, *p++);
638 printf ("/stop_memory/%d/%d", mcnt, *p++);
642 printf ("/duplicate/%d", *p++);
652 register int c, last = -100;
653 register int in_range = 0;
655 printf ("/charset [%s",
656 (re_opcode_t) *(p - 1) == charset_not ? "^" : "");
658 assert (p + *p < pend);
660 for (c = 0; c < 256; c++)
662 && (p[1 + (c/8)] & (1 << (c % 8))))
664 /* Are we starting a range? */
665 if (last + 1 == c && ! in_range)
670 /* Have we broken a range? */
671 else if (last + 1 != c && in_range)
700 case on_failure_jump:
701 extract_number_and_incr (&mcnt, &p);
702 printf ("/on_failure_jump to %d", p + mcnt - start);
705 case on_failure_keep_string_jump:
706 extract_number_and_incr (&mcnt, &p);
707 printf ("/on_failure_keep_string_jump to %d", p + mcnt - start);
710 case dummy_failure_jump:
711 extract_number_and_incr (&mcnt, &p);
712 printf ("/dummy_failure_jump to %d", p + mcnt - start);
715 case push_dummy_failure:
716 printf ("/push_dummy_failure");
720 extract_number_and_incr (&mcnt, &p);
721 printf ("/maybe_pop_jump to %d", p + mcnt - start);
724 case pop_failure_jump:
725 extract_number_and_incr (&mcnt, &p);
726 printf ("/pop_failure_jump to %d", p + mcnt - start);
730 extract_number_and_incr (&mcnt, &p);
731 printf ("/jump_past_alt to %d", p + mcnt - start);
735 extract_number_and_incr (&mcnt, &p);
736 printf ("/jump to %d", p + mcnt - start);
740 extract_number_and_incr (&mcnt, &p);
741 extract_number_and_incr (&mcnt2, &p);
742 printf ("/succeed_n to %d, %d times", p + mcnt - start, mcnt2);
746 extract_number_and_incr (&mcnt, &p);
747 extract_number_and_incr (&mcnt2, &p);
748 printf ("/jump_n to %d, %d times", p + mcnt - start, mcnt2);
752 extract_number_and_incr (&mcnt, &p);
753 extract_number_and_incr (&mcnt2, &p);
754 printf ("/set_number_at location %d to %d", p + mcnt - start, mcnt2);
758 printf ("/wordbound");
762 printf ("/notwordbound");
774 printf ("/before_dot");
782 printf ("/after_dot");
786 printf ("/syntaxspec");
788 printf ("/%d", mcnt);
792 printf ("/notsyntaxspec");
794 printf ("/%d", mcnt);
799 printf ("/wordchar");
803 printf ("/notwordchar");
815 printf ("?%d", *(p-1));
821 printf ("%d:\tend of pattern.\n", p - start);
826 print_compiled_pattern (bufp)
827 struct re_pattern_buffer *bufp;
829 unsigned char *buffer = bufp->buffer;
831 print_partial_compiled_pattern (buffer, buffer + bufp->used);
832 printf ("%d bytes used/%d bytes allocated.\n", bufp->used, bufp->allocated);
834 if (bufp->fastmap_accurate && bufp->fastmap)
836 printf ("fastmap: ");
837 print_fastmap (bufp->fastmap);
840 printf ("re_nsub: %d\t", bufp->re_nsub);
841 printf ("regs_alloc: %d\t", bufp->regs_allocated);
842 printf ("can_be_null: %d\t", bufp->can_be_null);
843 printf ("newline_anchor: %d\n", bufp->newline_anchor);
844 printf ("no_sub: %d\t", bufp->no_sub);
845 printf ("not_bol: %d\t", bufp->not_bol);
846 printf ("not_eol: %d\t", bufp->not_eol);
847 printf ("syntax: %d\n", bufp->syntax);
848 /* Perhaps we should print the translate table? */
853 print_double_string (where, string1, size1, string2, size2)
866 if (FIRST_STRING_P (where))
868 for (this_char = where - string1; this_char < size1; this_char++)
869 putchar (string1[this_char]);
874 for (this_char = where - string2; this_char < size2; this_char++)
875 putchar (string2[this_char]);
879 #else /* not DEBUG */
884 #define DEBUG_STATEMENT(e)
885 #define DEBUG_PRINT1(x)
886 #define DEBUG_PRINT2(x1, x2)
887 #define DEBUG_PRINT3(x1, x2, x3)
888 #define DEBUG_PRINT4(x1, x2, x3, x4)
889 #define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
890 #define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
892 #endif /* not DEBUG */
894 /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
895 also be assigned to arbitrarily: each pattern buffer stores its own
896 syntax, so it can be changed between regex compilations. */
897 /* This has no initializer because initialized variables in Emacs
898 become read-only after dumping. */
899 reg_syntax_t re_syntax_options;
902 /* Specify the precise syntax of regexps for compilation. This provides
903 for compatibility for various utilities which historically have
904 different, incompatible syntaxes.
906 The argument SYNTAX is a bit mask comprised of the various bits
907 defined in regex.h. We return the old syntax. */
910 re_set_syntax (syntax)
913 reg_syntax_t ret = re_syntax_options;
915 re_syntax_options = syntax;
919 /* This table gives an error message for each of the error codes listed
920 in regex.h. Obviously the order here has to be same as there.
921 POSIX doesn't require that we do anything for REG_NOERROR,
922 but why not be nice? */
924 static const char *re_error_msgid[] =
925 { "Success", /* REG_NOERROR */
926 "No match", /* REG_NOMATCH */
927 "Invalid regular expression", /* REG_BADPAT */
928 "Invalid collation character", /* REG_ECOLLATE */
929 "Invalid character class name", /* REG_ECTYPE */
930 "Trailing backslash", /* REG_EESCAPE */
931 "Invalid back reference", /* REG_ESUBREG */
932 "Unmatched [ or [^", /* REG_EBRACK */
933 "Unmatched ( or \\(", /* REG_EPAREN */
934 "Unmatched \\{", /* REG_EBRACE */
935 "Invalid content of \\{\\}", /* REG_BADBR */
936 "Invalid range end", /* REG_ERANGE */
937 "Memory exhausted", /* REG_ESPACE */
938 "Invalid preceding regular expression", /* REG_BADRPT */
939 "Premature end of regular expression", /* REG_EEND */
940 "Regular expression too big", /* REG_ESIZE */
941 "Unmatched ) or \\)", /* REG_ERPAREN */
944 /* Avoiding alloca during matching, to placate r_alloc. */
946 /* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
947 searching and matching functions should not call alloca. On some
948 systems, alloca is implemented in terms of malloc, and if we're
949 using the relocating allocator routines, then malloc could cause a
950 relocation, which might (if the strings being searched are in the
951 ralloc heap) shift the data out from underneath the regexp
954 Here's another reason to avoid allocation: Emacs
955 processes input from X in a signal handler; processing X input may
956 call malloc; if input arrives while a matching routine is calling
957 malloc, then we're scrod. But Emacs can't just block input while
958 calling matching routines; then we don't notice interrupts when
959 they come in. So, Emacs blocks input around all regexp calls
960 except the matching calls, which it leaves unprotected, in the
961 faith that they will not malloc. */
963 /* Normally, this is fine. */
964 #define MATCH_MAY_ALLOCATE
966 /* When using GNU C, we are not REALLY using the C alloca, no matter
967 what config.h may say. So don't take precautions for it. */
972 /* The match routines may not allocate if (1) they would do it with malloc
973 and (2) it's not safe for them to use malloc.
974 Note that if REL_ALLOC is defined, matching would not use malloc for the
975 failure stack, but we would still use it for the register vectors;
976 so REL_ALLOC should not affect this. */
977 #if (defined (C_ALLOCA) || defined (REGEX_MALLOC)) && defined (emacs)
978 #undef MATCH_MAY_ALLOCATE
982 /* Failure stack declarations and macros; both re_compile_fastmap and
983 re_match_2 use a failure stack. These have to be macros because of
984 REGEX_ALLOCATE_STACK. */
987 /* Number of failure points for which to initially allocate space
988 when matching. If this number is exceeded, we allocate more
989 space, so it is not a hard limit. */
990 #ifndef INIT_FAILURE_ALLOC
991 #define INIT_FAILURE_ALLOC 5
994 /* Roughly the maximum number of failure points on the stack. Would be
995 exactly that if always used MAX_FAILURE_SPACE each time we failed.
996 This is a variable only so users of regex can assign to it; we never
997 change it ourselves. */
998 #if defined (MATCH_MAY_ALLOCATE)
999 int re_max_failures = 200000;
1001 int re_max_failures = 2000;
1004 union fail_stack_elt
1006 unsigned char *pointer;
1010 typedef union fail_stack_elt fail_stack_elt_t;
1014 fail_stack_elt_t *stack;
1016 unsigned avail; /* Offset of next open position. */
1019 #define FAIL_STACK_EMPTY() (fail_stack.avail == 0)
1020 #define FAIL_STACK_PTR_EMPTY() (fail_stack_ptr->avail == 0)
1021 #define FAIL_STACK_FULL() (fail_stack.avail == fail_stack.size)
1024 /* Define macros to initialize and free the failure stack.
1025 Do `return -2' if the alloc fails. */
1027 #ifdef MATCH_MAY_ALLOCATE
1028 #define INIT_FAIL_STACK() \
1030 fail_stack.stack = (fail_stack_elt_t *) \
1031 REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * sizeof (fail_stack_elt_t)); \
1033 if (fail_stack.stack == NULL) \
1036 fail_stack.size = INIT_FAILURE_ALLOC; \
1037 fail_stack.avail = 0; \
1040 #define RESET_FAIL_STACK() REGEX_FREE_STACK (fail_stack.stack)
1042 #define INIT_FAIL_STACK() \
1044 fail_stack.avail = 0; \
1047 #define RESET_FAIL_STACK()
1051 /* Double the size of FAIL_STACK, up to approximately `re_max_failures' items.
1053 Return 1 if succeeds, and 0 if either ran out of memory
1054 allocating space for it or it was already too large.
1056 REGEX_REALLOCATE_STACK requires `destination' be declared. */
1058 #define DOUBLE_FAIL_STACK(fail_stack) \
1059 ((fail_stack).size > re_max_failures * MAX_FAILURE_ITEMS \
1061 : ((fail_stack).stack = (fail_stack_elt_t *) \
1062 REGEX_REALLOCATE_STACK ((fail_stack).stack, \
1063 (fail_stack).size * sizeof (fail_stack_elt_t), \
1064 ((fail_stack).size << 1) * sizeof (fail_stack_elt_t)), \
1066 (fail_stack).stack == NULL \
1068 : ((fail_stack).size <<= 1, \
1072 /* Push pointer POINTER on FAIL_STACK.
1073 Return 1 if was able to do so and 0 if ran out of memory allocating
1075 #define PUSH_PATTERN_OP(POINTER, FAIL_STACK) \
1076 ((FAIL_STACK_FULL () \
1077 && !DOUBLE_FAIL_STACK (FAIL_STACK)) \
1079 : ((FAIL_STACK).stack[(FAIL_STACK).avail++].pointer = POINTER, \
1082 /* Push a pointer value onto the failure stack.
1083 Assumes the variable `fail_stack'. Probably should only
1084 be called from within `PUSH_FAILURE_POINT'. */
1085 #define PUSH_FAILURE_POINTER(item) \
1086 fail_stack.stack[fail_stack.avail++].pointer = (unsigned char *) (item)
1088 /* This pushes an integer-valued item onto the failure stack.
1089 Assumes the variable `fail_stack'. Probably should only
1090 be called from within `PUSH_FAILURE_POINT'. */
1091 #define PUSH_FAILURE_INT(item) \
1092 fail_stack.stack[fail_stack.avail++].integer = (item)
1094 /* Push a fail_stack_elt_t value onto the failure stack.
1095 Assumes the variable `fail_stack'. Probably should only
1096 be called from within `PUSH_FAILURE_POINT'. */
1097 #define PUSH_FAILURE_ELT(item) \
1098 fail_stack.stack[fail_stack.avail++] = (item)
1100 /* These three POP... operations complement the three PUSH... operations.
1101 All assume that `fail_stack' is nonempty. */
1102 #define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
1103 #define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
1104 #define POP_FAILURE_ELT() fail_stack.stack[--fail_stack.avail]
1106 /* Used to omit pushing failure point id's when we're not debugging. */
1108 #define DEBUG_PUSH PUSH_FAILURE_INT
1109 #define DEBUG_POP(item_addr) *(item_addr) = POP_FAILURE_INT ()
1111 #define DEBUG_PUSH(item)
1112 #define DEBUG_POP(item_addr)
1116 /* Push the information about the state we will need
1117 if we ever fail back to it.
1119 Requires variables fail_stack, regstart, regend, reg_info, and
1120 num_regs be declared. DOUBLE_FAIL_STACK requires `destination' be
1123 Does `return FAILURE_CODE' if runs out of memory. */
1125 #define PUSH_FAILURE_POINT(pattern_place, string_place, failure_code) \
1127 char *destination; \
1128 /* Must be int, so when we don't save any registers, the arithmetic \
1129 of 0 + -1 isn't done as unsigned. */ \
1132 DEBUG_STATEMENT (failure_id++); \
1133 DEBUG_STATEMENT (nfailure_points_pushed++); \
1134 DEBUG_PRINT2 ("\nPUSH_FAILURE_POINT #%u:\n", failure_id); \
1135 DEBUG_PRINT2 (" Before push, next avail: %d\n", (fail_stack).avail);\
1136 DEBUG_PRINT2 (" size: %d\n", (fail_stack).size);\
1138 DEBUG_PRINT2 (" slots needed: %d\n", NUM_FAILURE_ITEMS); \
1139 DEBUG_PRINT2 (" available: %d\n", REMAINING_AVAIL_SLOTS); \
1141 /* Ensure we have enough space allocated for what we will push. */ \
1142 while (REMAINING_AVAIL_SLOTS < NUM_FAILURE_ITEMS) \
1144 if (!DOUBLE_FAIL_STACK (fail_stack)) \
1145 return failure_code; \
1147 DEBUG_PRINT2 ("\n Doubled stack; size now: %d\n", \
1148 (fail_stack).size); \
1149 DEBUG_PRINT2 (" slots available: %d\n", REMAINING_AVAIL_SLOTS);\
1152 /* Push the info, starting with the registers. */ \
1153 DEBUG_PRINT1 ("\n"); \
1155 for (this_reg = lowest_active_reg; this_reg <= highest_active_reg; \
1158 DEBUG_PRINT2 (" Pushing reg: %d\n", this_reg); \
1159 DEBUG_STATEMENT (num_regs_pushed++); \
1161 DEBUG_PRINT2 (" start: 0x%x\n", regstart[this_reg]); \
1162 PUSH_FAILURE_POINTER (regstart[this_reg]); \
1164 DEBUG_PRINT2 (" end: 0x%x\n", regend[this_reg]); \
1165 PUSH_FAILURE_POINTER (regend[this_reg]); \
1167 DEBUG_PRINT2 (" info: 0x%x\n ", reg_info[this_reg]); \
1168 DEBUG_PRINT2 (" match_null=%d", \
1169 REG_MATCH_NULL_STRING_P (reg_info[this_reg])); \
1170 DEBUG_PRINT2 (" active=%d", IS_ACTIVE (reg_info[this_reg])); \
1171 DEBUG_PRINT2 (" matched_something=%d", \
1172 MATCHED_SOMETHING (reg_info[this_reg])); \
1173 DEBUG_PRINT2 (" ever_matched=%d", \
1174 EVER_MATCHED_SOMETHING (reg_info[this_reg])); \
1175 DEBUG_PRINT1 ("\n"); \
1176 PUSH_FAILURE_ELT (reg_info[this_reg].word); \
1179 DEBUG_PRINT2 (" Pushing low active reg: %d\n", lowest_active_reg);\
1180 PUSH_FAILURE_INT (lowest_active_reg); \
1182 DEBUG_PRINT2 (" Pushing high active reg: %d\n", highest_active_reg);\
1183 PUSH_FAILURE_INT (highest_active_reg); \
1185 DEBUG_PRINT2 (" Pushing pattern 0x%x: ", pattern_place); \
1186 DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern_place, pend); \
1187 PUSH_FAILURE_POINTER (pattern_place); \
1189 DEBUG_PRINT2 (" Pushing string 0x%x: `", string_place); \
1190 DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2, \
1192 DEBUG_PRINT1 ("'\n"); \
1193 PUSH_FAILURE_POINTER (string_place); \
1195 DEBUG_PRINT2 (" Pushing failure id: %u\n", failure_id); \
1196 DEBUG_PUSH (failure_id); \
1199 /* This is the number of items that are pushed and popped on the stack
1200 for each register. */
1201 #define NUM_REG_ITEMS 3
1203 /* Individual items aside from the registers. */
1205 #define NUM_NONREG_ITEMS 5 /* Includes failure point id. */
1207 #define NUM_NONREG_ITEMS 4
1210 /* We push at most this many items on the stack. */
1211 #define MAX_FAILURE_ITEMS ((num_regs - 1) * NUM_REG_ITEMS + NUM_NONREG_ITEMS)
1213 /* We actually push this many items. */
1214 #define NUM_FAILURE_ITEMS \
1215 ((highest_active_reg - lowest_active_reg + 1) * NUM_REG_ITEMS \
1218 /* How many items can still be added to the stack without overflowing it. */
1219 #define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
1222 /* Pops what PUSH_FAIL_STACK pushes.
1224 We restore into the parameters, all of which should be lvalues:
1225 STR -- the saved data position.
1226 PAT -- the saved pattern position.
1227 LOW_REG, HIGH_REG -- the highest and lowest active registers.
1228 REGSTART, REGEND -- arrays of string positions.
1229 REG_INFO -- array of information about each subexpression.
1231 Also assumes the variables `fail_stack' and (if debugging), `bufp',
1232 `pend', `string1', `size1', `string2', and `size2'. */
1234 #define POP_FAILURE_POINT(str, pat, low_reg, high_reg, regstart, regend, reg_info)\
1236 DEBUG_STATEMENT (fail_stack_elt_t failure_id;) \
1238 const unsigned char *string_temp; \
1240 assert (!FAIL_STACK_EMPTY ()); \
1242 /* Remove failure points and point to how many regs pushed. */ \
1243 DEBUG_PRINT1 ("POP_FAILURE_POINT:\n"); \
1244 DEBUG_PRINT2 (" Before pop, next avail: %d\n", fail_stack.avail); \
1245 DEBUG_PRINT2 (" size: %d\n", fail_stack.size); \
1247 assert (fail_stack.avail >= NUM_NONREG_ITEMS); \
1249 DEBUG_POP (&failure_id); \
1250 DEBUG_PRINT2 (" Popping failure id: %u\n", failure_id); \
1252 /* If the saved string location is NULL, it came from an \
1253 on_failure_keep_string_jump opcode, and we want to throw away the \
1254 saved NULL, thus retaining our current position in the string. */ \
1255 string_temp = POP_FAILURE_POINTER (); \
1256 if (string_temp != NULL) \
1257 str = (const char *) string_temp; \
1259 DEBUG_PRINT2 (" Popping string 0x%x: `", str); \
1260 DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2); \
1261 DEBUG_PRINT1 ("'\n"); \
1263 pat = (unsigned char *) POP_FAILURE_POINTER (); \
1264 DEBUG_PRINT2 (" Popping pattern 0x%x: ", pat); \
1265 DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend); \
1267 /* Restore register info. */ \
1268 high_reg = (unsigned) POP_FAILURE_INT (); \
1269 DEBUG_PRINT2 (" Popping high active reg: %d\n", high_reg); \
1271 low_reg = (unsigned) POP_FAILURE_INT (); \
1272 DEBUG_PRINT2 (" Popping low active reg: %d\n", low_reg); \
1274 for (this_reg = high_reg; this_reg >= low_reg; this_reg--) \
1276 DEBUG_PRINT2 (" Popping reg: %d\n", this_reg); \
1278 reg_info[this_reg].word = POP_FAILURE_ELT (); \
1279 DEBUG_PRINT2 (" info: 0x%x\n", reg_info[this_reg]); \
1281 regend[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1282 DEBUG_PRINT2 (" end: 0x%x\n", regend[this_reg]); \
1284 regstart[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1285 DEBUG_PRINT2 (" start: 0x%x\n", regstart[this_reg]); \
1288 set_regs_matched_done = 0; \
1289 DEBUG_STATEMENT (nfailure_points_popped++); \
1290 } /* POP_FAILURE_POINT */
1294 /* Structure for per-register (a.k.a. per-group) information.
1295 Other register information, such as the
1296 starting and ending positions (which are addresses), and the list of
1297 inner groups (which is a bits list) are maintained in separate
1300 We are making a (strictly speaking) nonportable assumption here: that
1301 the compiler will pack our bit fields into something that fits into
1302 the type of `word', i.e., is something that fits into one item on the
1307 fail_stack_elt_t word;
1310 /* This field is one if this group can match the empty string,
1311 zero if not. If not yet determined, `MATCH_NULL_UNSET_VALUE'. */
1312 #define MATCH_NULL_UNSET_VALUE 3
1313 unsigned match_null_string_p : 2;
1314 unsigned is_active : 1;
1315 unsigned matched_something : 1;
1316 unsigned ever_matched_something : 1;
1318 } register_info_type;
1320 #define REG_MATCH_NULL_STRING_P(R) ((R).bits.match_null_string_p)
1321 #define IS_ACTIVE(R) ((R).bits.is_active)
1322 #define MATCHED_SOMETHING(R) ((R).bits.matched_something)
1323 #define EVER_MATCHED_SOMETHING(R) ((R).bits.ever_matched_something)
1326 /* Call this when have matched a real character; it sets `matched' flags
1327 for the subexpressions which we are currently inside. Also records
1328 that those subexprs have matched. */
1329 #define SET_REGS_MATCHED() \
1332 if (!set_regs_matched_done) \
1335 set_regs_matched_done = 1; \
1336 for (r = lowest_active_reg; r <= highest_active_reg; r++) \
1338 MATCHED_SOMETHING (reg_info[r]) \
1339 = EVER_MATCHED_SOMETHING (reg_info[r]) \
1346 /* Registers are set to a sentinel when they haven't yet matched. */
1347 static char reg_unset_dummy;
1348 #define REG_UNSET_VALUE (®_unset_dummy)
1349 #define REG_UNSET(e) ((e) == REG_UNSET_VALUE)
1351 /* Subroutine declarations and macros for regex_compile. */
1353 static void store_op1 (), store_op2 ();
1354 static void insert_op1 (), insert_op2 ();
1355 static boolean at_begline_loc_p (), at_endline_loc_p ();
1356 static boolean group_in_compile_stack ();
1357 static reg_errcode_t compile_range ();
1359 /* Fetch the next character in the uncompiled pattern---translating it
1360 if necessary. Also cast from a signed character in the constant
1361 string passed to us by the user to an unsigned char that we can use
1362 as an array index (in, e.g., `translate'). */
1363 #define PATFETCH(c) \
1364 do {if (p == pend) return REG_EEND; \
1365 c = (unsigned char) *p++; \
1366 if (translate) c = translate[c]; \
1369 /* Fetch the next character in the uncompiled pattern, with no
1371 #define PATFETCH_RAW(c) \
1372 do {if (p == pend) return REG_EEND; \
1373 c = (unsigned char) *p++; \
1376 /* Go backwards one character in the pattern. */
1377 #define PATUNFETCH p--
1380 /* If `translate' is non-null, return translate[D], else just D. We
1381 cast the subscript to translate because some data is declared as
1382 `char *', to avoid warnings when a string constant is passed. But
1383 when we use a character as a subscript we must make it unsigned. */
1384 #define TRANSLATE(d) (translate ? translate[(unsigned char) (d)] : (d))
1387 /* Macros for outputting the compiled pattern into `buffer'. */
1389 /* If the buffer isn't allocated when it comes in, use this. */
1390 #define INIT_BUF_SIZE 32
1392 /* Make sure we have at least N more bytes of space in buffer. */
1393 #define GET_BUFFER_SPACE(n) \
1394 while (b - bufp->buffer + (n) > bufp->allocated) \
1397 /* Make sure we have one more byte of buffer space and then add C to it. */
1398 #define BUF_PUSH(c) \
1400 GET_BUFFER_SPACE (1); \
1401 *b++ = (unsigned char) (c); \
1405 /* Ensure we have two more bytes of buffer space and then append C1 and C2. */
1406 #define BUF_PUSH_2(c1, c2) \
1408 GET_BUFFER_SPACE (2); \
1409 *b++ = (unsigned char) (c1); \
1410 *b++ = (unsigned char) (c2); \
1414 /* As with BUF_PUSH_2, except for three bytes. */
1415 #define BUF_PUSH_3(c1, c2, c3) \
1417 GET_BUFFER_SPACE (3); \
1418 *b++ = (unsigned char) (c1); \
1419 *b++ = (unsigned char) (c2); \
1420 *b++ = (unsigned char) (c3); \
1424 /* Store a jump with opcode OP at LOC to location TO. We store a
1425 relative address offset by the three bytes the jump itself occupies. */
1426 #define STORE_JUMP(op, loc, to) \
1427 store_op1 (op, loc, (to) - (loc) - 3)
1429 /* Likewise, for a two-argument jump. */
1430 #define STORE_JUMP2(op, loc, to, arg) \
1431 store_op2 (op, loc, (to) - (loc) - 3, arg)
1433 /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
1434 #define INSERT_JUMP(op, loc, to) \
1435 insert_op1 (op, loc, (to) - (loc) - 3, b)
1437 /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
1438 #define INSERT_JUMP2(op, loc, to, arg) \
1439 insert_op2 (op, loc, (to) - (loc) - 3, arg, b)
1442 /* This is not an arbitrary limit: the arguments which represent offsets
1443 into the pattern are two bytes long. So if 2^16 bytes turns out to
1444 be too small, many things would have to change. */
1445 #define MAX_BUF_SIZE (1L << 16)
1448 /* Extend the buffer by twice its current size via realloc and
1449 reset the pointers that pointed into the old block to point to the
1450 correct places in the new one. If extending the buffer results in it
1451 being larger than MAX_BUF_SIZE, then flag memory exhausted. */
1452 #define EXTEND_BUFFER() \
1454 unsigned char *old_buffer = bufp->buffer; \
1455 if (bufp->allocated == MAX_BUF_SIZE) \
1457 bufp->allocated <<= 1; \
1458 if (bufp->allocated > MAX_BUF_SIZE) \
1459 bufp->allocated = MAX_BUF_SIZE; \
1460 bufp->buffer = (unsigned char *) realloc (bufp->buffer, bufp->allocated);\
1461 if (bufp->buffer == NULL) \
1462 return REG_ESPACE; \
1463 /* If the buffer moved, move all the pointers into it. */ \
1464 if (old_buffer != bufp->buffer) \
1466 b = (b - old_buffer) + bufp->buffer; \
1467 begalt = (begalt - old_buffer) + bufp->buffer; \
1468 if (fixup_alt_jump) \
1469 fixup_alt_jump = (fixup_alt_jump - old_buffer) + bufp->buffer;\
1471 laststart = (laststart - old_buffer) + bufp->buffer; \
1472 if (pending_exact) \
1473 pending_exact = (pending_exact - old_buffer) + bufp->buffer; \
1478 /* Since we have one byte reserved for the register number argument to
1479 {start,stop}_memory, the maximum number of groups we can report
1480 things about is what fits in that byte. */
1481 #define MAX_REGNUM 255
1483 /* But patterns can have more than `MAX_REGNUM' registers. We just
1484 ignore the excess. */
1485 typedef unsigned regnum_t;
1488 /* Macros for the compile stack. */
1490 /* Since offsets can go either forwards or backwards, this type needs to
1491 be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
1492 typedef int pattern_offset_t;
1496 pattern_offset_t begalt_offset;
1497 pattern_offset_t fixup_alt_jump;
1498 pattern_offset_t inner_group_offset;
1499 pattern_offset_t laststart_offset;
1501 } compile_stack_elt_t;
1506 compile_stack_elt_t *stack;
1508 unsigned avail; /* Offset of next open position. */
1509 } compile_stack_type;
1512 #define INIT_COMPILE_STACK_SIZE 32
1514 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
1515 #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
1517 /* The next available element. */
1518 #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
1521 /* Set the bit for character C in a list. */
1522 #define SET_LIST_BIT(c) \
1523 (b[((unsigned char) (c)) / BYTEWIDTH] \
1524 |= 1 << (((unsigned char) c) % BYTEWIDTH))
1527 /* Get the next unsigned number in the uncompiled pattern. */
1528 #define GET_UNSIGNED_NUMBER(num) \
1532 while (ISDIGIT (c)) \
1536 num = num * 10 + c - '0'; \
1544 #define CHAR_CLASS_MAX_LENGTH 6 /* Namely, `xdigit'. */
1546 #define IS_CHAR_CLASS(string) \
1547 (STREQ (string, "alpha") || STREQ (string, "upper") \
1548 || STREQ (string, "lower") || STREQ (string, "digit") \
1549 || STREQ (string, "alnum") || STREQ (string, "xdigit") \
1550 || STREQ (string, "space") || STREQ (string, "print") \
1551 || STREQ (string, "punct") || STREQ (string, "graph") \
1552 || STREQ (string, "cntrl") || STREQ (string, "blank"))
1554 #ifndef MATCH_MAY_ALLOCATE
1556 /* If we cannot allocate large objects within re_match_2_internal,
1557 we make the fail stack and register vectors global.
1558 The fail stack, we grow to the maximum size when a regexp
1560 The register vectors, we adjust in size each time we
1561 compile a regexp, according to the number of registers it needs. */
1563 static fail_stack_type fail_stack;
1565 /* Size with which the following vectors are currently allocated.
1566 That is so we can make them bigger as needed,
1567 but never make them smaller. */
1568 static int regs_allocated_size;
1570 static const char ** regstart, ** regend;
1571 static const char ** old_regstart, ** old_regend;
1572 static const char **best_regstart, **best_regend;
1573 static register_info_type *reg_info;
1574 static const char **reg_dummy;
1575 static register_info_type *reg_info_dummy;
1577 /* Make the register vectors big enough for NUM_REGS registers,
1578 but don't make them smaller. */
1581 regex_grow_registers (num_regs)
1584 if (num_regs > regs_allocated_size)
1586 RETALLOC_IF (regstart, num_regs, const char *);
1587 RETALLOC_IF (regend, num_regs, const char *);
1588 RETALLOC_IF (old_regstart, num_regs, const char *);
1589 RETALLOC_IF (old_regend, num_regs, const char *);
1590 RETALLOC_IF (best_regstart, num_regs, const char *);
1591 RETALLOC_IF (best_regend, num_regs, const char *);
1592 RETALLOC_IF (reg_info, num_regs, register_info_type);
1593 RETALLOC_IF (reg_dummy, num_regs, const char *);
1594 RETALLOC_IF (reg_info_dummy, num_regs, register_info_type);
1596 regs_allocated_size = num_regs;
1600 #endif /* not MATCH_MAY_ALLOCATE */
1602 /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
1603 Returns one of error codes defined in `regex.h', or zero for success.
1605 Assumes the `allocated' (and perhaps `buffer') and `translate'
1606 fields are set in BUFP on entry.
1608 If it succeeds, results are put in BUFP (if it returns an error, the
1609 contents of BUFP are undefined):
1610 `buffer' is the compiled pattern;
1611 `syntax' is set to SYNTAX;
1612 `used' is set to the length of the compiled pattern;
1613 `fastmap_accurate' is zero;
1614 `re_nsub' is the number of subexpressions in PATTERN;
1615 `not_bol' and `not_eol' are zero;
1617 The `fastmap' and `newline_anchor' fields are neither
1618 examined nor set. */
1620 /* Return, freeing storage we allocated. */
1621 #define FREE_STACK_RETURN(value) \
1622 return (free (compile_stack.stack), value)
1624 static reg_errcode_t
1625 regex_compile (pattern, size, syntax, bufp)
1626 const char *pattern;
1628 reg_syntax_t syntax;
1629 struct re_pattern_buffer *bufp;
1631 /* We fetch characters from PATTERN here. Even though PATTERN is
1632 `char *' (i.e., signed), we declare these variables as unsigned, so
1633 they can be reliably used as array indices. */
1634 register unsigned char c, c1;
1636 /* A random temporary spot in PATTERN. */
1639 /* Points to the end of the buffer, where we should append. */
1640 register unsigned char *b;
1642 /* Keeps track of unclosed groups. */
1643 compile_stack_type compile_stack;
1645 /* Points to the current (ending) position in the pattern. */
1646 const char *p = pattern;
1647 const char *pend = pattern + size;
1649 /* How to translate the characters in the pattern. */
1650 char *translate = bufp->translate;
1652 /* Address of the count-byte of the most recently inserted `exactn'
1653 command. This makes it possible to tell if a new exact-match
1654 character can be added to that command or if the character requires
1655 a new `exactn' command. */
1656 unsigned char *pending_exact = 0;
1658 /* Address of start of the most recently finished expression.
1659 This tells, e.g., postfix * where to find the start of its
1660 operand. Reset at the beginning of groups and alternatives. */
1661 unsigned char *laststart = 0;
1663 /* Address of beginning of regexp, or inside of last group. */
1664 unsigned char *begalt;
1666 /* Place in the uncompiled pattern (i.e., the {) to
1667 which to go back if the interval is invalid. */
1668 const char *beg_interval;
1670 /* Address of the place where a forward jump should go to the end of
1671 the containing expression. Each alternative of an `or' -- except the
1672 last -- ends with a forward jump of this sort. */
1673 unsigned char *fixup_alt_jump = 0;
1675 /* Counts open-groups as they are encountered. Remembered for the
1676 matching close-group on the compile stack, so the same register
1677 number is put in the stop_memory as the start_memory. */
1678 regnum_t regnum = 0;
1681 DEBUG_PRINT1 ("\nCompiling pattern: ");
1684 unsigned debug_count;
1686 for (debug_count = 0; debug_count < size; debug_count++)
1687 putchar (pattern[debug_count]);
1692 /* Initialize the compile stack. */
1693 compile_stack.stack = TALLOC (INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
1694 if (compile_stack.stack == NULL)
1697 compile_stack.size = INIT_COMPILE_STACK_SIZE;
1698 compile_stack.avail = 0;
1700 /* Initialize the pattern buffer. */
1701 bufp->syntax = syntax;
1702 bufp->fastmap_accurate = 0;
1703 bufp->not_bol = bufp->not_eol = 0;
1705 /* Set `used' to zero, so that if we return an error, the pattern
1706 printer (for debugging) will think there's no pattern. We reset it
1710 /* Always count groups, whether or not bufp->no_sub is set. */
1713 #if !defined (emacs) && !defined (SYNTAX_TABLE)
1714 /* Initialize the syntax table. */
1715 init_syntax_once ();
1718 if (bufp->allocated == 0)
1721 { /* If zero allocated, but buffer is non-null, try to realloc
1722 enough space. This loses if buffer's address is bogus, but
1723 that is the user's responsibility. */
1724 RETALLOC (bufp->buffer, INIT_BUF_SIZE, unsigned char);
1727 { /* Caller did not allocate a buffer. Do it for them. */
1728 bufp->buffer = TALLOC (INIT_BUF_SIZE, unsigned char);
1730 if (!bufp->buffer) FREE_STACK_RETURN (REG_ESPACE);
1732 bufp->allocated = INIT_BUF_SIZE;
1735 begalt = b = bufp->buffer;
1737 /* Loop through the uncompiled pattern until we're at the end. */
1746 if ( /* If at start of pattern, it's an operator. */
1748 /* If context independent, it's an operator. */
1749 || syntax & RE_CONTEXT_INDEP_ANCHORS
1750 /* Otherwise, depends on what's come before. */
1751 || at_begline_loc_p (pattern, p, syntax))
1761 if ( /* If at end of pattern, it's an operator. */
1763 /* If context independent, it's an operator. */
1764 || syntax & RE_CONTEXT_INDEP_ANCHORS
1765 /* Otherwise, depends on what's next. */
1766 || at_endline_loc_p (p, pend, syntax))
1776 if ((syntax & RE_BK_PLUS_QM)
1777 || (syntax & RE_LIMITED_OPS))
1781 /* If there is no previous pattern... */
1784 if (syntax & RE_CONTEXT_INVALID_OPS)
1785 FREE_STACK_RETURN (REG_BADRPT);
1786 else if (!(syntax & RE_CONTEXT_INDEP_OPS))
1791 /* Are we optimizing this jump? */
1792 boolean keep_string_p = false;
1794 /* 1 means zero (many) matches is allowed. */
1795 char zero_times_ok = 0, many_times_ok = 0;
1797 /* If there is a sequence of repetition chars, collapse it
1798 down to just one (the right one). We can't combine
1799 interval operators with these because of, e.g., `a{2}*',
1800 which should only match an even number of `a's. */
1804 zero_times_ok |= c != '+';
1805 many_times_ok |= c != '?';
1813 || (!(syntax & RE_BK_PLUS_QM) && (c == '+' || c == '?')))
1816 else if (syntax & RE_BK_PLUS_QM && c == '\\')
1818 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
1821 if (!(c1 == '+' || c1 == '?'))
1836 /* If we get here, we found another repeat character. */
1839 /* Star, etc. applied to an empty pattern is equivalent
1840 to an empty pattern. */
1844 /* Now we know whether or not zero matches is allowed
1845 and also whether or not two or more matches is allowed. */
1847 { /* More than one repetition is allowed, so put in at the
1848 end a backward relative jump from `b' to before the next
1849 jump we're going to put in below (which jumps from
1850 laststart to after this jump).
1852 But if we are at the `*' in the exact sequence `.*\n',
1853 insert an unconditional jump backwards to the .,
1854 instead of the beginning of the loop. This way we only
1855 push a failure point once, instead of every time
1856 through the loop. */
1857 assert (p - 1 > pattern);
1859 /* Allocate the space for the jump. */
1860 GET_BUFFER_SPACE (3);
1862 /* We know we are not at the first character of the pattern,
1863 because laststart was nonzero. And we've already
1864 incremented `p', by the way, to be the character after
1865 the `*'. Do we have to do something analogous here
1866 for null bytes, because of RE_DOT_NOT_NULL? */
1867 if (TRANSLATE (*(p - 2)) == TRANSLATE ('.')
1869 && p < pend && TRANSLATE (*p) == TRANSLATE ('\n')
1870 && !(syntax & RE_DOT_NEWLINE))
1871 { /* We have .*\n. */
1872 STORE_JUMP (jump, b, laststart);
1873 keep_string_p = true;
1876 /* Anything else. */
1877 STORE_JUMP (maybe_pop_jump, b, laststart - 3);
1879 /* We've added more stuff to the buffer. */
1883 /* On failure, jump from laststart to b + 3, which will be the
1884 end of the buffer after this jump is inserted. */
1885 GET_BUFFER_SPACE (3);
1886 INSERT_JUMP (keep_string_p ? on_failure_keep_string_jump
1894 /* At least one repetition is required, so insert a
1895 `dummy_failure_jump' before the initial
1896 `on_failure_jump' instruction of the loop. This
1897 effects a skip over that instruction the first time
1898 we hit that loop. */
1899 GET_BUFFER_SPACE (3);
1900 INSERT_JUMP (dummy_failure_jump, laststart, laststart + 6);
1915 boolean had_char_class = false;
1917 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
1919 /* Ensure that we have enough space to push a charset: the
1920 opcode, the length count, and the bitset; 34 bytes in all. */
1921 GET_BUFFER_SPACE (34);
1925 /* We test `*p == '^' twice, instead of using an if
1926 statement, so we only need one BUF_PUSH. */
1927 BUF_PUSH (*p == '^' ? charset_not : charset);
1931 /* Remember the first position in the bracket expression. */
1934 /* Push the number of bytes in the bitmap. */
1935 BUF_PUSH ((1 << BYTEWIDTH) / BYTEWIDTH);
1937 /* Clear the whole map. */
1938 bzero (b, (1 << BYTEWIDTH) / BYTEWIDTH);
1940 /* charset_not matches newline according to a syntax bit. */
1941 if ((re_opcode_t) b[-2] == charset_not
1942 && (syntax & RE_HAT_LISTS_NOT_NEWLINE))
1943 SET_LIST_BIT ('\n');
1945 /* Read in characters and ranges, setting map bits. */
1948 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
1952 /* \ might escape characters inside [...] and [^...]. */
1953 if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\')
1955 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
1962 /* Could be the end of the bracket expression. If it's
1963 not (i.e., when the bracket expression is `[]' so
1964 far), the ']' character bit gets set way below. */
1965 if (c == ']' && p != p1 + 1)
1968 /* Look ahead to see if it's a range when the last thing
1969 was a character class. */
1970 if (had_char_class && c == '-' && *p != ']')
1971 FREE_STACK_RETURN (REG_ERANGE);
1973 /* Look ahead to see if it's a range when the last thing
1974 was a character: if this is a hyphen not at the
1975 beginning or the end of a list, then it's the range
1978 && !(p - 2 >= pattern && p[-2] == '[')
1979 && !(p - 3 >= pattern && p[-3] == '[' && p[-2] == '^')
1983 = compile_range (&p, pend, translate, syntax, b);
1984 if (ret != REG_NOERROR) FREE_STACK_RETURN (ret);
1987 else if (p[0] == '-' && p[1] != ']')
1988 { /* This handles ranges made up of characters only. */
1991 /* Move past the `-'. */
1994 ret = compile_range (&p, pend, translate, syntax, b);
1995 if (ret != REG_NOERROR) FREE_STACK_RETURN (ret);
1998 /* See if we're at the beginning of a possible character
2001 else if (syntax & RE_CHAR_CLASSES && c == '[' && *p == ':')
2002 { /* Leave room for the null. */
2003 char str[CHAR_CLASS_MAX_LENGTH + 1];
2008 /* If pattern is `[[:'. */
2009 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2014 if (c == ':' || c == ']' || p == pend
2015 || c1 == CHAR_CLASS_MAX_LENGTH)
2021 /* If isn't a word bracketed by `[:' and:`]':
2022 undo the ending character, the letters, and leave
2023 the leading `:' and `[' (but set bits for them). */
2024 if (c == ':' && *p == ']')
2027 boolean is_alnum = STREQ (str, "alnum");
2028 boolean is_alpha = STREQ (str, "alpha");
2029 boolean is_blank = STREQ (str, "blank");
2030 boolean is_cntrl = STREQ (str, "cntrl");
2031 boolean is_digit = STREQ (str, "digit");
2032 boolean is_graph = STREQ (str, "graph");
2033 boolean is_lower = STREQ (str, "lower");
2034 boolean is_print = STREQ (str, "print");
2035 boolean is_punct = STREQ (str, "punct");
2036 boolean is_space = STREQ (str, "space");
2037 boolean is_upper = STREQ (str, "upper");
2038 boolean is_xdigit = STREQ (str, "xdigit");
2040 if (!IS_CHAR_CLASS (str))
2041 FREE_STACK_RETURN (REG_ECTYPE);
2043 /* Throw away the ] at the end of the character
2047 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2049 for (ch = 0; ch < 1 << BYTEWIDTH; ch++)
2051 /* This was split into 3 if's to
2052 avoid an arbitrary limit in some compiler. */
2053 if ( (is_alnum && ISALNUM (ch))
2054 || (is_alpha && ISALPHA (ch))
2055 || (is_blank && ISBLANK (ch))
2056 || (is_cntrl && ISCNTRL (ch)))
2058 if ( (is_digit && ISDIGIT (ch))
2059 || (is_graph && ISGRAPH (ch))
2060 || (is_lower && ISLOWER (ch))
2061 || (is_print && ISPRINT (ch)))
2063 if ( (is_punct && ISPUNCT (ch))
2064 || (is_space && ISSPACE (ch))
2065 || (is_upper && ISUPPER (ch))
2066 || (is_xdigit && ISXDIGIT (ch)))
2069 had_char_class = true;
2078 had_char_class = false;
2083 had_char_class = false;
2088 /* Discard any (non)matching list bytes that are all 0 at the
2089 end of the map. Decrease the map-length byte too. */
2090 while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
2098 if (syntax & RE_NO_BK_PARENS)
2105 if (syntax & RE_NO_BK_PARENS)
2112 if (syntax & RE_NEWLINE_ALT)
2119 if (syntax & RE_NO_BK_VBAR)
2126 if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
2127 goto handle_interval;
2133 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2135 /* Do not translate the character after the \, so that we can
2136 distinguish, e.g., \B from \b, even if we normally would
2137 translate, e.g., B to b. */
2143 if (syntax & RE_NO_BK_PARENS)
2144 goto normal_backslash;
2150 if (COMPILE_STACK_FULL)
2152 RETALLOC (compile_stack.stack, compile_stack.size << 1,
2153 compile_stack_elt_t);
2154 if (compile_stack.stack == NULL) return REG_ESPACE;
2156 compile_stack.size <<= 1;
2159 /* These are the values to restore when we hit end of this
2160 group. They are all relative offsets, so that if the
2161 whole pattern moves because of realloc, they will still
2163 COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
2164 COMPILE_STACK_TOP.fixup_alt_jump
2165 = fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
2166 COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
2167 COMPILE_STACK_TOP.regnum = regnum;
2169 /* We will eventually replace the 0 with the number of
2170 groups inner to this one. But do not push a
2171 start_memory for groups beyond the last one we can
2172 represent in the compiled pattern. */
2173 if (regnum <= MAX_REGNUM)
2175 COMPILE_STACK_TOP.inner_group_offset = b - bufp->buffer + 2;
2176 BUF_PUSH_3 (start_memory, regnum, 0);
2179 compile_stack.avail++;
2184 /* If we've reached MAX_REGNUM groups, then this open
2185 won't actually generate any code, so we'll have to
2186 clear pending_exact explicitly. */
2192 if (syntax & RE_NO_BK_PARENS) goto normal_backslash;
2194 if (COMPILE_STACK_EMPTY)
2195 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
2196 goto normal_backslash;
2198 FREE_STACK_RETURN (REG_ERPAREN);
2202 { /* Push a dummy failure point at the end of the
2203 alternative for a possible future
2204 `pop_failure_jump' to pop. See comments at
2205 `push_dummy_failure' in `re_match_2'. */
2206 BUF_PUSH (push_dummy_failure);
2208 /* We allocated space for this jump when we assigned
2209 to `fixup_alt_jump', in the `handle_alt' case below. */
2210 STORE_JUMP (jump_past_alt, fixup_alt_jump, b - 1);
2213 /* See similar code for backslashed left paren above. */
2214 if (COMPILE_STACK_EMPTY)
2215 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
2218 FREE_STACK_RETURN (REG_ERPAREN);
2220 /* Since we just checked for an empty stack above, this
2221 ``can't happen''. */
2222 assert (compile_stack.avail != 0);
2224 /* We don't just want to restore into `regnum', because
2225 later groups should continue to be numbered higher,
2226 as in `(ab)c(de)' -- the second group is #2. */
2227 regnum_t this_group_regnum;
2229 compile_stack.avail--;
2230 begalt = bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
2232 = COMPILE_STACK_TOP.fixup_alt_jump
2233 ? bufp->buffer + COMPILE_STACK_TOP.fixup_alt_jump - 1
2235 laststart = bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
2236 this_group_regnum = COMPILE_STACK_TOP.regnum;
2237 /* If we've reached MAX_REGNUM groups, then this open
2238 won't actually generate any code, so we'll have to
2239 clear pending_exact explicitly. */
2242 /* We're at the end of the group, so now we know how many
2243 groups were inside this one. */
2244 if (this_group_regnum <= MAX_REGNUM)
2246 unsigned char *inner_group_loc
2247 = bufp->buffer + COMPILE_STACK_TOP.inner_group_offset;
2249 *inner_group_loc = regnum - this_group_regnum;
2250 BUF_PUSH_3 (stop_memory, this_group_regnum,
2251 regnum - this_group_regnum);
2257 case '|': /* `\|'. */
2258 if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
2259 goto normal_backslash;
2261 if (syntax & RE_LIMITED_OPS)
2264 /* Insert before the previous alternative a jump which
2265 jumps to this alternative if the former fails. */
2266 GET_BUFFER_SPACE (3);
2267 INSERT_JUMP (on_failure_jump, begalt, b + 6);
2271 /* The alternative before this one has a jump after it
2272 which gets executed if it gets matched. Adjust that
2273 jump so it will jump to this alternative's analogous
2274 jump (put in below, which in turn will jump to the next
2275 (if any) alternative's such jump, etc.). The last such
2276 jump jumps to the correct final destination. A picture:
2282 If we are at `b', then fixup_alt_jump right now points to a
2283 three-byte space after `a'. We'll put in the jump, set
2284 fixup_alt_jump to right after `b', and leave behind three
2285 bytes which we'll fill in when we get to after `c'. */
2288 STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
2290 /* Mark and leave space for a jump after this alternative,
2291 to be filled in later either by next alternative or
2292 when know we're at the end of a series of alternatives. */
2294 GET_BUFFER_SPACE (3);
2303 /* If \{ is a literal. */
2304 if (!(syntax & RE_INTERVALS)
2305 /* If we're at `\{' and it's not the open-interval
2307 || ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
2308 || (p - 2 == pattern && p == pend))
2309 goto normal_backslash;
2313 /* If got here, then the syntax allows intervals. */
2315 /* At least (most) this many matches must be made. */
2316 int lower_bound = -1, upper_bound = -1;
2318 beg_interval = p - 1;
2322 if (syntax & RE_NO_BK_BRACES)
2323 goto unfetch_interval;
2325 FREE_STACK_RETURN (REG_EBRACE);
2328 GET_UNSIGNED_NUMBER (lower_bound);
2332 GET_UNSIGNED_NUMBER (upper_bound);
2333 if (upper_bound < 0) upper_bound = RE_DUP_MAX;
2336 /* Interval such as `{1}' => match exactly once. */
2337 upper_bound = lower_bound;
2339 if (lower_bound < 0 || upper_bound > RE_DUP_MAX
2340 || lower_bound > upper_bound)
2342 if (syntax & RE_NO_BK_BRACES)
2343 goto unfetch_interval;
2345 FREE_STACK_RETURN (REG_BADBR);
2348 if (!(syntax & RE_NO_BK_BRACES))
2350 if (c != '\\') FREE_STACK_RETURN (REG_EBRACE);
2357 if (syntax & RE_NO_BK_BRACES)
2358 goto unfetch_interval;
2360 FREE_STACK_RETURN (REG_BADBR);
2363 /* We just parsed a valid interval. */
2365 /* If it's invalid to have no preceding re. */
2368 if (syntax & RE_CONTEXT_INVALID_OPS)
2369 FREE_STACK_RETURN (REG_BADRPT);
2370 else if (syntax & RE_CONTEXT_INDEP_OPS)
2373 goto unfetch_interval;
2376 /* If the upper bound is zero, don't want to succeed at
2377 all; jump from `laststart' to `b + 3', which will be
2378 the end of the buffer after we insert the jump. */
2379 if (upper_bound == 0)
2381 GET_BUFFER_SPACE (3);
2382 INSERT_JUMP (jump, laststart, b + 3);
2386 /* Otherwise, we have a nontrivial interval. When
2387 we're all done, the pattern will look like:
2388 set_number_at <jump count> <upper bound>
2389 set_number_at <succeed_n count> <lower bound>
2390 succeed_n <after jump addr> <succeed_n count>
2392 jump_n <succeed_n addr> <jump count>
2393 (The upper bound and `jump_n' are omitted if
2394 `upper_bound' is 1, though.) */
2396 { /* If the upper bound is > 1, we need to insert
2397 more at the end of the loop. */
2398 unsigned nbytes = 10 + (upper_bound > 1) * 10;
2400 GET_BUFFER_SPACE (nbytes);
2402 /* Initialize lower bound of the `succeed_n', even
2403 though it will be set during matching by its
2404 attendant `set_number_at' (inserted next),
2405 because `re_compile_fastmap' needs to know.
2406 Jump to the `jump_n' we might insert below. */
2407 INSERT_JUMP2 (succeed_n, laststart,
2408 b + 5 + (upper_bound > 1) * 5,
2412 /* Code to initialize the lower bound. Insert
2413 before the `succeed_n'. The `5' is the last two
2414 bytes of this `set_number_at', plus 3 bytes of
2415 the following `succeed_n'. */
2416 insert_op2 (set_number_at, laststart, 5, lower_bound, b);
2419 if (upper_bound > 1)
2420 { /* More than one repetition is allowed, so
2421 append a backward jump to the `succeed_n'
2422 that starts this interval.
2424 When we've reached this during matching,
2425 we'll have matched the interval once, so
2426 jump back only `upper_bound - 1' times. */
2427 STORE_JUMP2 (jump_n, b, laststart + 5,
2431 /* The location we want to set is the second
2432 parameter of the `jump_n'; that is `b-2' as
2433 an absolute address. `laststart' will be
2434 the `set_number_at' we're about to insert;
2435 `laststart+3' the number to set, the source
2436 for the relative address. But we are
2437 inserting into the middle of the pattern --
2438 so everything is getting moved up by 5.
2439 Conclusion: (b - 2) - (laststart + 3) + 5,
2440 i.e., b - laststart.
2442 We insert this at the beginning of the loop
2443 so that if we fail during matching, we'll
2444 reinitialize the bounds. */
2445 insert_op2 (set_number_at, laststart, b - laststart,
2446 upper_bound - 1, b);
2451 beg_interval = NULL;
2456 /* If an invalid interval, match the characters as literals. */
2457 assert (beg_interval);
2459 beg_interval = NULL;
2461 /* normal_char and normal_backslash need `c'. */
2464 if (!(syntax & RE_NO_BK_BRACES))
2466 if (p > pattern && p[-1] == '\\')
2467 goto normal_backslash;
2472 /* There is no way to specify the before_dot and after_dot
2473 operators. rms says this is ok. --karl */
2481 BUF_PUSH_2 (syntaxspec, syntax_spec_code[c]);
2487 BUF_PUSH_2 (notsyntaxspec, syntax_spec_code[c]);
2494 BUF_PUSH (wordchar);
2500 BUF_PUSH (notwordchar);
2513 BUF_PUSH (wordbound);
2517 BUF_PUSH (notwordbound);
2528 case '1': case '2': case '3': case '4': case '5':
2529 case '6': case '7': case '8': case '9':
2530 if (syntax & RE_NO_BK_REFS)
2536 FREE_STACK_RETURN (REG_ESUBREG);
2538 /* Can't back reference to a subexpression if inside of it. */
2539 if (group_in_compile_stack (compile_stack, c1))
2543 BUF_PUSH_2 (duplicate, c1);
2549 if (syntax & RE_BK_PLUS_QM)
2552 goto normal_backslash;
2556 /* You might think it would be useful for \ to mean
2557 not to translate; but if we don't translate it
2558 it will never match anything. */
2566 /* Expects the character in `c'. */
2568 /* If no exactn currently being built. */
2571 /* If last exactn not at current position. */
2572 || pending_exact + *pending_exact + 1 != b
2574 /* We have only one byte following the exactn for the count. */
2575 || *pending_exact == (1 << BYTEWIDTH) - 1
2577 /* If followed by a repetition operator. */
2578 || *p == '*' || *p == '^'
2579 || ((syntax & RE_BK_PLUS_QM)
2580 ? *p == '\\' && (p[1] == '+' || p[1] == '?')
2581 : (*p == '+' || *p == '?'))
2582 || ((syntax & RE_INTERVALS)
2583 && ((syntax & RE_NO_BK_BRACES)
2585 : (p[0] == '\\' && p[1] == '{'))))
2587 /* Start building a new exactn. */
2591 BUF_PUSH_2 (exactn, 0);
2592 pending_exact = b - 1;
2599 } /* while p != pend */
2602 /* Through the pattern now. */
2605 STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
2607 if (!COMPILE_STACK_EMPTY)
2608 FREE_STACK_RETURN (REG_EPAREN);
2610 /* If we don't want backtracking, force success
2611 the first time we reach the end of the compiled pattern. */
2612 if (syntax & RE_NO_POSIX_BACKTRACKING)
2615 free (compile_stack.stack);
2617 /* We have succeeded; set the length of the buffer. */
2618 bufp->used = b - bufp->buffer;
2623 DEBUG_PRINT1 ("\nCompiled pattern: \n");
2624 print_compiled_pattern (bufp);
2628 #ifndef MATCH_MAY_ALLOCATE
2629 /* Initialize the failure stack to the largest possible stack. This
2630 isn't necessary unless we're trying to avoid calling alloca in
2631 the search and match routines. */
2633 int num_regs = bufp->re_nsub + 1;
2635 /* Since DOUBLE_FAIL_STACK refuses to double only if the current size
2636 is strictly greater than re_max_failures, the largest possible stack
2637 is 2 * re_max_failures failure points. */
2638 if (fail_stack.size < (2 * re_max_failures * MAX_FAILURE_ITEMS))
2640 fail_stack.size = (2 * re_max_failures * MAX_FAILURE_ITEMS);
2643 if (! fail_stack.stack)
2645 = (fail_stack_elt_t *) xmalloc (fail_stack.size
2646 * sizeof (fail_stack_elt_t));
2649 = (fail_stack_elt_t *) xrealloc (fail_stack.stack,
2651 * sizeof (fail_stack_elt_t)));
2652 #else /* not emacs */
2653 if (! fail_stack.stack)
2655 = (fail_stack_elt_t *) malloc (fail_stack.size
2656 * sizeof (fail_stack_elt_t));
2659 = (fail_stack_elt_t *) realloc (fail_stack.stack,
2661 * sizeof (fail_stack_elt_t)));
2662 #endif /* not emacs */
2665 regex_grow_registers (num_regs);
2667 #endif /* not MATCH_MAY_ALLOCATE */
2670 } /* regex_compile */
2672 /* Subroutines for `regex_compile'. */
2674 /* Store OP at LOC followed by two-byte integer parameter ARG. */
2677 store_op1 (op, loc, arg)
2682 *loc = (unsigned char) op;
2683 STORE_NUMBER (loc + 1, arg);
2687 /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
2690 store_op2 (op, loc, arg1, arg2)
2695 *loc = (unsigned char) op;
2696 STORE_NUMBER (loc + 1, arg1);
2697 STORE_NUMBER (loc + 3, arg2);
2701 /* Copy the bytes from LOC to END to open up three bytes of space at LOC
2702 for OP followed by two-byte integer parameter ARG. */
2705 insert_op1 (op, loc, arg, end)
2711 register unsigned char *pfrom = end;
2712 register unsigned char *pto = end + 3;
2714 while (pfrom != loc)
2717 store_op1 (op, loc, arg);
2721 /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
2724 insert_op2 (op, loc, arg1, arg2, end)
2730 register unsigned char *pfrom = end;
2731 register unsigned char *pto = end + 5;
2733 while (pfrom != loc)
2736 store_op2 (op, loc, arg1, arg2);
2740 /* P points to just after a ^ in PATTERN. Return true if that ^ comes
2741 after an alternative or a begin-subexpression. We assume there is at
2742 least one character before the ^. */
2745 at_begline_loc_p (pattern, p, syntax)
2746 const char *pattern, *p;
2747 reg_syntax_t syntax;
2749 const char *prev = p - 2;
2750 boolean prev_prev_backslash = prev > pattern && prev[-1] == '\\';
2753 /* After a subexpression? */
2754 (*prev == '(' && (syntax & RE_NO_BK_PARENS || prev_prev_backslash))
2755 /* After an alternative? */
2756 || (*prev == '|' && (syntax & RE_NO_BK_VBAR || prev_prev_backslash));
2760 /* The dual of at_begline_loc_p. This one is for $. We assume there is
2761 at least one character after the $, i.e., `P < PEND'. */
2764 at_endline_loc_p (p, pend, syntax)
2765 const char *p, *pend;
2768 const char *next = p;
2769 boolean next_backslash = *next == '\\';
2770 const char *next_next = p + 1 < pend ? p + 1 : 0;
2773 /* Before a subexpression? */
2774 (syntax & RE_NO_BK_PARENS ? *next == ')'
2775 : next_backslash && next_next && *next_next == ')')
2776 /* Before an alternative? */
2777 || (syntax & RE_NO_BK_VBAR ? *next == '|'
2778 : next_backslash && next_next && *next_next == '|');
2782 /* Returns true if REGNUM is in one of COMPILE_STACK's elements and
2783 false if it's not. */
2786 group_in_compile_stack (compile_stack, regnum)
2787 compile_stack_type compile_stack;
2792 for (this_element = compile_stack.avail - 1;
2795 if (compile_stack.stack[this_element].regnum == regnum)
2802 /* Read the ending character of a range (in a bracket expression) from the
2803 uncompiled pattern *P_PTR (which ends at PEND). We assume the
2804 starting character is in `P[-2]'. (`P[-1]' is the character `-'.)
2805 Then we set the translation of all bits between the starting and
2806 ending characters (inclusive) in the compiled pattern B.
2808 Return an error code.
2810 We use these short variable names so we can use the same macros as
2811 `regex_compile' itself. */
2813 static reg_errcode_t
2814 compile_range (p_ptr, pend, translate, syntax, b)
2815 const char **p_ptr, *pend;
2817 reg_syntax_t syntax;
2822 const char *p = *p_ptr;
2823 int range_start, range_end;
2828 /* Even though the pattern is a signed `char *', we need to fetch
2829 with unsigned char *'s; if the high bit of the pattern character
2830 is set, the range endpoints will be negative if we fetch using a
2833 We also want to fetch the endpoints without translating them; the
2834 appropriate translation is done in the bit-setting loop below. */
2835 /* The SVR4 compiler on the 3B2 had trouble with unsigned const char *. */
2836 range_start = ((const unsigned char *) p)[-2];
2837 range_end = ((const unsigned char *) p)[0];
2839 /* Have to increment the pointer into the pattern string, so the
2840 caller isn't still at the ending character. */
2843 /* If the start is after the end, the range is empty. */
2844 if (range_start > range_end)
2845 return syntax & RE_NO_EMPTY_RANGES ? REG_ERANGE : REG_NOERROR;
2847 /* Here we see why `this_char' has to be larger than an `unsigned
2848 char' -- the range is inclusive, so if `range_end' == 0xff
2849 (assuming 8-bit characters), we would otherwise go into an infinite
2850 loop, since all characters <= 0xff. */
2851 for (this_char = range_start; this_char <= range_end; this_char++)
2853 SET_LIST_BIT (TRANSLATE (this_char));
2859 /* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
2860 BUFP. A fastmap records which of the (1 << BYTEWIDTH) possible
2861 characters can start a string that matches the pattern. This fastmap
2862 is used by re_search to skip quickly over impossible starting points.
2864 The caller must supply the address of a (1 << BYTEWIDTH)-byte data
2865 area as BUFP->fastmap.
2867 We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
2870 Returns 0 if we succeed, -2 if an internal error. */
2873 re_compile_fastmap (bufp)
2874 struct re_pattern_buffer *bufp;
2877 #ifdef MATCH_MAY_ALLOCATE
2878 fail_stack_type fail_stack;
2880 #ifndef REGEX_MALLOC
2883 /* We don't push any register information onto the failure stack. */
2884 unsigned num_regs = 0;
2886 register char *fastmap = bufp->fastmap;
2887 unsigned char *pattern = bufp->buffer;
2888 unsigned long size = bufp->used;
2889 unsigned char *p = pattern;
2890 register unsigned char *pend = pattern + size;
2892 /* This holds the pointer to the failure stack, when
2893 it is allocated relocatably. */
2894 fail_stack_elt_t *failure_stack_ptr;
2896 /* Assume that each path through the pattern can be null until
2897 proven otherwise. We set this false at the bottom of switch
2898 statement, to which we get only if a particular path doesn't
2899 match the empty string. */
2900 boolean path_can_be_null = true;
2902 /* We aren't doing a `succeed_n' to begin with. */
2903 boolean succeed_n_p = false;
2905 assert (fastmap != NULL && p != NULL);
2908 bzero (fastmap, 1 << BYTEWIDTH); /* Assume nothing's valid. */
2909 bufp->fastmap_accurate = 1; /* It will be when we're done. */
2910 bufp->can_be_null = 0;
2914 if (p == pend || *p == succeed)
2916 /* We have reached the (effective) end of pattern. */
2917 if (!FAIL_STACK_EMPTY ())
2919 bufp->can_be_null |= path_can_be_null;
2921 /* Reset for next path. */
2922 path_can_be_null = true;
2924 p = fail_stack.stack[--fail_stack.avail].pointer;
2932 /* We should never be about to go beyond the end of the pattern. */
2935 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
2938 /* I guess the idea here is to simply not bother with a fastmap
2939 if a backreference is used, since it's too hard to figure out
2940 the fastmap for the corresponding group. Setting
2941 `can_be_null' stops `re_search_2' from using the fastmap, so
2942 that is all we do. */
2944 bufp->can_be_null = 1;
2948 /* Following are the cases which match a character. These end
2957 for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
2958 if (p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH)))
2964 /* Chars beyond end of map must be allowed. */
2965 for (j = *p * BYTEWIDTH; j < (1 << BYTEWIDTH); j++)
2968 for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
2969 if (!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))))
2975 for (j = 0; j < (1 << BYTEWIDTH); j++)
2976 if (SYNTAX (j) == Sword)
2982 for (j = 0; j < (1 << BYTEWIDTH); j++)
2983 if (SYNTAX (j) != Sword)
2990 int fastmap_newline = fastmap['\n'];
2992 /* `.' matches anything ... */
2993 for (j = 0; j < (1 << BYTEWIDTH); j++)
2996 /* ... except perhaps newline. */
2997 if (!(bufp->syntax & RE_DOT_NEWLINE))
2998 fastmap['\n'] = fastmap_newline;
3000 /* Return if we have already set `can_be_null'; if we have,
3001 then the fastmap is irrelevant. Something's wrong here. */
3002 else if (bufp->can_be_null)
3005 /* Otherwise, have to check alternative paths. */
3012 for (j = 0; j < (1 << BYTEWIDTH); j++)
3013 if (SYNTAX (j) == (enum syntaxcode) k)
3020 for (j = 0; j < (1 << BYTEWIDTH); j++)
3021 if (SYNTAX (j) != (enum syntaxcode) k)
3026 /* All cases after this match the empty string. These end with
3034 #endif /* not emacs */
3046 case push_dummy_failure:
3051 case pop_failure_jump:
3052 case maybe_pop_jump:
3055 case dummy_failure_jump:
3056 EXTRACT_NUMBER_AND_INCR (j, p);
3061 /* Jump backward implies we just went through the body of a
3062 loop and matched nothing. Opcode jumped to should be
3063 `on_failure_jump' or `succeed_n'. Just treat it like an
3064 ordinary jump. For a * loop, it has pushed its failure
3065 point already; if so, discard that as redundant. */
3066 if ((re_opcode_t) *p != on_failure_jump
3067 && (re_opcode_t) *p != succeed_n)
3071 EXTRACT_NUMBER_AND_INCR (j, p);
3074 /* If what's on the stack is where we are now, pop it. */
3075 if (!FAIL_STACK_EMPTY ()
3076 && fail_stack.stack[fail_stack.avail - 1].pointer == p)
3082 case on_failure_jump:
3083 case on_failure_keep_string_jump:
3084 handle_on_failure_jump:
3085 EXTRACT_NUMBER_AND_INCR (j, p);
3087 /* For some patterns, e.g., `(a?)?', `p+j' here points to the
3088 end of the pattern. We don't want to push such a point,
3089 since when we restore it above, entering the switch will
3090 increment `p' past the end of the pattern. We don't need
3091 to push such a point since we obviously won't find any more
3092 fastmap entries beyond `pend'. Such a pattern can match
3093 the null string, though. */
3096 if (!PUSH_PATTERN_OP (p + j, fail_stack))
3098 RESET_FAIL_STACK ();
3103 bufp->can_be_null = 1;
3107 EXTRACT_NUMBER_AND_INCR (k, p); /* Skip the n. */
3108 succeed_n_p = false;
3115 /* Get to the number of times to succeed. */
3118 /* Increment p past the n for when k != 0. */
3119 EXTRACT_NUMBER_AND_INCR (k, p);
3123 succeed_n_p = true; /* Spaghetti code alert. */
3124 goto handle_on_failure_jump;
3141 abort (); /* We have listed all the cases. */
3144 /* Getting here means we have found the possible starting
3145 characters for one path of the pattern -- and that the empty
3146 string does not match. We need not follow this path further.
3147 Instead, look at the next alternative (remembered on the
3148 stack), or quit if no more. The test at the top of the loop
3149 does these things. */
3150 path_can_be_null = false;
3154 /* Set `can_be_null' for the last path (also the first path, if the
3155 pattern is empty). */
3156 bufp->can_be_null |= path_can_be_null;
3159 RESET_FAIL_STACK ();
3161 } /* re_compile_fastmap */
3163 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
3164 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
3165 this memory for recording register information. STARTS and ENDS
3166 must be allocated using the malloc library routine, and must each
3167 be at least NUM_REGS * sizeof (regoff_t) bytes long.
3169 If NUM_REGS == 0, then subsequent matches should allocate their own
3172 Unless this function is called, the first search or match using
3173 PATTERN_BUFFER will allocate its own register data, without
3174 freeing the old data. */
3177 re_set_registers (bufp, regs, num_regs, starts, ends)
3178 struct re_pattern_buffer *bufp;
3179 struct re_registers *regs;
3181 regoff_t *starts, *ends;
3185 bufp->regs_allocated = REGS_REALLOCATE;
3186 regs->num_regs = num_regs;
3187 regs->start = starts;
3192 bufp->regs_allocated = REGS_UNALLOCATED;
3194 regs->start = regs->end = (regoff_t *) 0;
3198 /* Searching routines. */
3200 /* Like re_search_2, below, but only one string is specified, and
3201 doesn't let you say where to stop matching. */
3204 re_search (bufp, string, size, startpos, range, regs)
3205 struct re_pattern_buffer *bufp;
3207 int size, startpos, range;
3208 struct re_registers *regs;
3210 return re_search_2 (bufp, NULL, 0, string, size, startpos, range,
3215 /* Using the compiled pattern in BUFP->buffer, first tries to match the
3216 virtual concatenation of STRING1 and STRING2, starting first at index
3217 STARTPOS, then at STARTPOS + 1, and so on.
3219 STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
3221 RANGE is how far to scan while trying to match. RANGE = 0 means try
3222 only at STARTPOS; in general, the last start tried is STARTPOS +
3225 In REGS, return the indices of the virtual concatenation of STRING1
3226 and STRING2 that matched the entire BUFP->buffer and its contained
3229 Do not consider matching one past the index STOP in the virtual
3230 concatenation of STRING1 and STRING2.
3232 We return either the position in the strings at which the match was
3233 found, -1 if no match, or -2 if error (such as failure
3237 re_search_2 (bufp, string1, size1, string2, size2, startpos, range, regs, stop)
3238 struct re_pattern_buffer *bufp;
3239 const char *string1, *string2;
3243 struct re_registers *regs;
3247 register char *fastmap = bufp->fastmap;
3248 register char *translate = bufp->translate;
3249 int total_size = size1 + size2;
3250 int endpos = startpos + range;
3252 /* Check for out-of-range STARTPOS. */
3253 if (startpos < 0 || startpos > total_size)
3256 /* Fix up RANGE if it might eventually take us outside
3257 the virtual concatenation of STRING1 and STRING2. */
3259 range = -1 - startpos;
3260 else if (endpos > total_size)
3261 range = total_size - startpos;
3263 /* If the search isn't to be a backwards one, don't waste time in a
3264 search for a pattern that must be anchored. */
3265 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == begbuf && range > 0)
3273 /* Update the fastmap now if not correct already. */
3274 if (fastmap && !bufp->fastmap_accurate)
3275 if (re_compile_fastmap (bufp) == -2)
3278 /* Loop through the string, looking for a place to start matching. */
3281 /* If a fastmap is supplied, skip quickly over characters that
3282 cannot be the start of a match. If the pattern can match the
3283 null string, however, we don't need to skip characters; we want
3284 the first null string. */
3285 if (fastmap && startpos < total_size && !bufp->can_be_null)
3287 if (range > 0) /* Searching forwards. */
3289 register const char *d;
3290 register int lim = 0;
3293 if (startpos < size1 && startpos + range >= size1)
3294 lim = range - (size1 - startpos);
3296 d = (startpos >= size1 ? string2 - size1 : string1) + startpos;
3298 /* Written out as an if-else to avoid testing `translate'
3302 && !fastmap[(unsigned char)
3303 translate[(unsigned char) *d++]])
3306 while (range > lim && !fastmap[(unsigned char) *d++])
3309 startpos += irange - range;
3311 else /* Searching backwards. */
3313 register char c = (size1 == 0 || startpos >= size1
3314 ? string2[startpos - size1]
3315 : string1[startpos]);
3317 if (!fastmap[(unsigned char) TRANSLATE (c)])
3322 /* If can't match the null string, and that's all we have left, fail. */
3323 if (range >= 0 && startpos == total_size && fastmap
3324 && !bufp->can_be_null)
3327 val = re_match_2_internal (bufp, string1, size1, string2, size2,
3328 startpos, regs, stop);
3329 #ifndef REGEX_MALLOC
3358 /* Declarations and macros for re_match_2. */
3360 static int bcmp_translate ();
3361 static boolean alt_match_null_string_p (),
3362 common_op_match_null_string_p (),
3363 group_match_null_string_p ();
3365 /* This converts PTR, a pointer into one of the search strings `string1'
3366 and `string2' into an offset from the beginning of that string. */
3367 #define POINTER_TO_OFFSET(ptr) \
3368 (FIRST_STRING_P (ptr) \
3369 ? ((regoff_t) ((ptr) - string1)) \
3370 : ((regoff_t) ((ptr) - string2 + size1)))
3372 /* Macros for dealing with the split strings in re_match_2. */
3374 #define MATCHING_IN_FIRST_STRING (dend == end_match_1)
3376 /* Call before fetching a character with *d. This switches over to
3377 string2 if necessary. */
3378 #define PREFETCH() \
3381 /* End of string2 => fail. */ \
3382 if (dend == end_match_2) \
3384 /* End of string1 => advance to string2. */ \
3386 dend = end_match_2; \
3390 /* Test if at very beginning or at very end of the virtual concatenation
3391 of `string1' and `string2'. If only one string, it's `string2'. */
3392 #define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
3393 #define AT_STRINGS_END(d) ((d) == end2)
3396 /* Test if D points to a character which is word-constituent. We have
3397 two special cases to check for: if past the end of string1, look at
3398 the first character in string2; and if before the beginning of
3399 string2, look at the last character in string1. */
3400 #define WORDCHAR_P(d) \
3401 (SYNTAX ((d) == end1 ? *string2 \
3402 : (d) == string2 - 1 ? *(end1 - 1) : *(d)) \
3405 /* Test if the character before D and the one at D differ with respect
3406 to being word-constituent. */
3407 #define AT_WORD_BOUNDARY(d) \
3408 (AT_STRINGS_BEG (d) || AT_STRINGS_END (d) \
3409 || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
3412 /* Free everything we malloc. */
3413 #ifdef MATCH_MAY_ALLOCATE
3414 #define FREE_VAR(var) if (var) REGEX_FREE (var); var = NULL
3415 #define FREE_VARIABLES() \
3417 REGEX_FREE_STACK (fail_stack.stack); \
3418 FREE_VAR (regstart); \
3419 FREE_VAR (regend); \
3420 FREE_VAR (old_regstart); \
3421 FREE_VAR (old_regend); \
3422 FREE_VAR (best_regstart); \
3423 FREE_VAR (best_regend); \
3424 FREE_VAR (reg_info); \
3425 FREE_VAR (reg_dummy); \
3426 FREE_VAR (reg_info_dummy); \
3429 #define FREE_VARIABLES() ((void)0) /* Do nothing! But inhibit gcc warning. */
3430 #endif /* not MATCH_MAY_ALLOCATE */
3432 /* These values must meet several constraints. They must not be valid
3433 register values; since we have a limit of 255 registers (because
3434 we use only one byte in the pattern for the register number), we can
3435 use numbers larger than 255. They must differ by 1, because of
3436 NUM_FAILURE_ITEMS above. And the value for the lowest register must
3437 be larger than the value for the highest register, so we do not try
3438 to actually save any registers when none are active. */
3439 #define NO_HIGHEST_ACTIVE_REG (1 << BYTEWIDTH)
3440 #define NO_LOWEST_ACTIVE_REG (NO_HIGHEST_ACTIVE_REG + 1)
3442 /* Matching routines. */
3444 #ifndef emacs /* Emacs never uses this. */
3445 /* re_match is like re_match_2 except it takes only a single string. */
3448 re_match (bufp, string, size, pos, regs)
3449 struct re_pattern_buffer *bufp;
3452 struct re_registers *regs;
3454 int result = re_match_2_internal (bufp, NULL, 0, string, size,
3459 #endif /* not emacs */
3462 /* re_match_2 matches the compiled pattern in BUFP against the
3463 the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
3464 and SIZE2, respectively). We start matching at POS, and stop
3467 If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
3468 store offsets for the substring each group matched in REGS. See the
3469 documentation for exactly how many groups we fill.
3471 We return -1 if no match, -2 if an internal error (such as the
3472 failure stack overflowing). Otherwise, we return the length of the
3473 matched substring. */
3476 re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
3477 struct re_pattern_buffer *bufp;
3478 const char *string1, *string2;
3481 struct re_registers *regs;
3484 int result = re_match_2_internal (bufp, string1, size1, string2, size2,
3490 /* This is a separate function so that we can force an alloca cleanup
3493 re_match_2_internal (bufp, string1, size1, string2, size2, pos, regs, stop)
3494 struct re_pattern_buffer *bufp;
3495 const char *string1, *string2;
3498 struct re_registers *regs;
3501 /* General temporaries. */
3505 /* Just past the end of the corresponding string. */
3506 const char *end1, *end2;
3508 /* Pointers into string1 and string2, just past the last characters in
3509 each to consider matching. */
3510 const char *end_match_1, *end_match_2;
3512 /* Where we are in the data, and the end of the current string. */
3513 const char *d, *dend;
3515 /* Where we are in the pattern, and the end of the pattern. */
3516 unsigned char *p = bufp->buffer;
3517 register unsigned char *pend = p + bufp->used;
3519 /* Mark the opcode just after a start_memory, so we can test for an
3520 empty subpattern when we get to the stop_memory. */
3521 unsigned char *just_past_start_mem = 0;
3523 /* We use this to map every character in the string. */
3524 char *translate = bufp->translate;
3526 /* Failure point stack. Each place that can handle a failure further
3527 down the line pushes a failure point on this stack. It consists of
3528 restart, regend, and reg_info for all registers corresponding to
3529 the subexpressions we're currently inside, plus the number of such
3530 registers, and, finally, two char *'s. The first char * is where
3531 to resume scanning the pattern; the second one is where to resume
3532 scanning the strings. If the latter is zero, the failure point is
3533 a ``dummy''; if a failure happens and the failure point is a dummy,
3534 it gets discarded and the next next one is tried. */
3535 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
3536 fail_stack_type fail_stack;
3539 static unsigned failure_id = 0;
3540 unsigned nfailure_points_pushed = 0, nfailure_points_popped = 0;
3543 /* This holds the pointer to the failure stack, when
3544 it is allocated relocatably. */
3545 fail_stack_elt_t *failure_stack_ptr;
3547 /* We fill all the registers internally, independent of what we
3548 return, for use in backreferences. The number here includes
3549 an element for register zero. */
3550 unsigned num_regs = bufp->re_nsub + 1;
3552 /* The currently active registers. */
3553 unsigned lowest_active_reg = NO_LOWEST_ACTIVE_REG;
3554 unsigned highest_active_reg = NO_HIGHEST_ACTIVE_REG;
3556 /* Information on the contents of registers. These are pointers into
3557 the input strings; they record just what was matched (on this
3558 attempt) by a subexpression part of the pattern, that is, the
3559 regnum-th regstart pointer points to where in the pattern we began
3560 matching and the regnum-th regend points to right after where we
3561 stopped matching the regnum-th subexpression. (The zeroth register
3562 keeps track of what the whole pattern matches.) */
3563 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3564 const char **regstart, **regend;
3567 /* If a group that's operated upon by a repetition operator fails to
3568 match anything, then the register for its start will need to be
3569 restored because it will have been set to wherever in the string we
3570 are when we last see its open-group operator. Similarly for a
3572 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3573 const char **old_regstart, **old_regend;
3576 /* The is_active field of reg_info helps us keep track of which (possibly
3577 nested) subexpressions we are currently in. The matched_something
3578 field of reg_info[reg_num] helps us tell whether or not we have
3579 matched any of the pattern so far this time through the reg_num-th
3580 subexpression. These two fields get reset each time through any
3581 loop their register is in. */
3582 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
3583 register_info_type *reg_info;
3586 /* The following record the register info as found in the above
3587 variables when we find a match better than any we've seen before.
3588 This happens as we backtrack through the failure points, which in
3589 turn happens only if we have not yet matched the entire string. */
3590 unsigned best_regs_set = false;
3591 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3592 const char **best_regstart, **best_regend;
3595 /* Logically, this is `best_regend[0]'. But we don't want to have to
3596 allocate space for that if we're not allocating space for anything
3597 else (see below). Also, we never need info about register 0 for
3598 any of the other register vectors, and it seems rather a kludge to
3599 treat `best_regend' differently than the rest. So we keep track of
3600 the end of the best match so far in a separate variable. We
3601 initialize this to NULL so that when we backtrack the first time
3602 and need to test it, it's not garbage. */
3603 const char *match_end = NULL;
3605 /* This helps SET_REGS_MATCHED avoid doing redundant work. */
3606 int set_regs_matched_done = 0;
3608 /* Used when we pop values we don't care about. */
3609 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3610 const char **reg_dummy;
3611 register_info_type *reg_info_dummy;
3615 /* Counts the total number of registers pushed. */
3616 unsigned num_regs_pushed = 0;
3619 DEBUG_PRINT1 ("\n\nEntering re_match_2.\n");
3623 #ifdef MATCH_MAY_ALLOCATE
3624 /* Do not bother to initialize all the register variables if there are
3625 no groups in the pattern, as it takes a fair amount of time. If
3626 there are groups, we include space for register 0 (the whole
3627 pattern), even though we never use it, since it simplifies the
3628 array indexing. We should fix this. */
3631 regstart = REGEX_TALLOC (num_regs, const char *);
3632 regend = REGEX_TALLOC (num_regs, const char *);
3633 old_regstart = REGEX_TALLOC (num_regs, const char *);
3634 old_regend = REGEX_TALLOC (num_regs, const char *);
3635 best_regstart = REGEX_TALLOC (num_regs, const char *);
3636 best_regend = REGEX_TALLOC (num_regs, const char *);
3637 reg_info = REGEX_TALLOC (num_regs, register_info_type);
3638 reg_dummy = REGEX_TALLOC (num_regs, const char *);
3639 reg_info_dummy = REGEX_TALLOC (num_regs, register_info_type);
3641 if (!(regstart && regend && old_regstart && old_regend && reg_info
3642 && best_regstart && best_regend && reg_dummy && reg_info_dummy))
3650 /* We must initialize all our variables to NULL, so that
3651 `FREE_VARIABLES' doesn't try to free them. */
3652 regstart = regend = old_regstart = old_regend = best_regstart
3653 = best_regend = reg_dummy = NULL;
3654 reg_info = reg_info_dummy = (register_info_type *) NULL;
3656 #endif /* MATCH_MAY_ALLOCATE */
3658 /* The starting position is bogus. */
3659 if (pos < 0 || pos > size1 + size2)
3665 /* Initialize subexpression text positions to -1 to mark ones that no
3666 start_memory/stop_memory has been seen for. Also initialize the
3667 register information struct. */
3668 for (mcnt = 1; mcnt < num_regs; mcnt++)
3670 regstart[mcnt] = regend[mcnt]
3671 = old_regstart[mcnt] = old_regend[mcnt] = REG_UNSET_VALUE;
3673 REG_MATCH_NULL_STRING_P (reg_info[mcnt]) = MATCH_NULL_UNSET_VALUE;
3674 IS_ACTIVE (reg_info[mcnt]) = 0;
3675 MATCHED_SOMETHING (reg_info[mcnt]) = 0;
3676 EVER_MATCHED_SOMETHING (reg_info[mcnt]) = 0;
3679 /* We move `string1' into `string2' if the latter's empty -- but not if
3680 `string1' is null. */
3681 if (size2 == 0 && string1 != NULL)
3688 end1 = string1 + size1;
3689 end2 = string2 + size2;
3691 /* Compute where to stop matching, within the two strings. */
3694 end_match_1 = string1 + stop;
3695 end_match_2 = string2;
3700 end_match_2 = string2 + stop - size1;
3703 /* `p' scans through the pattern as `d' scans through the data.
3704 `dend' is the end of the input string that `d' points within. `d'
3705 is advanced into the following input string whenever necessary, but
3706 this happens before fetching; therefore, at the beginning of the
3707 loop, `d' can be pointing at the end of a string, but it cannot
3709 if (size1 > 0 && pos <= size1)
3716 d = string2 + pos - size1;
3720 DEBUG_PRINT1 ("The compiled pattern is: ");
3721 DEBUG_PRINT_COMPILED_PATTERN (bufp, p, pend);
3722 DEBUG_PRINT1 ("The string to match is: `");
3723 DEBUG_PRINT_DOUBLE_STRING (d, string1, size1, string2, size2);
3724 DEBUG_PRINT1 ("'\n");
3726 /* This loops over pattern commands. It exits by returning from the
3727 function if the match is complete, or it drops through if the match
3728 fails at this starting point in the input data. */
3731 DEBUG_PRINT2 ("\n0x%x: ", p);
3734 { /* End of pattern means we might have succeeded. */
3735 DEBUG_PRINT1 ("end of pattern ... ");
3737 /* If we haven't matched the entire string, and we want the
3738 longest match, try backtracking. */
3739 if (d != end_match_2)
3741 /* 1 if this match ends in the same string (string1 or string2)
3742 as the best previous match. */
3743 boolean same_str_p = (FIRST_STRING_P (match_end)
3744 == MATCHING_IN_FIRST_STRING);
3745 /* 1 if this match is the best seen so far. */
3746 boolean best_match_p;
3748 /* AIX compiler got confused when this was combined
3749 with the previous declaration. */
3751 best_match_p = d > match_end;
3753 best_match_p = !MATCHING_IN_FIRST_STRING;
3755 DEBUG_PRINT1 ("backtracking.\n");
3757 if (!FAIL_STACK_EMPTY ())
3758 { /* More failure points to try. */
3760 /* If exceeds best match so far, save it. */
3761 if (!best_regs_set || best_match_p)
3763 best_regs_set = true;
3766 DEBUG_PRINT1 ("\nSAVING match as best so far.\n");
3768 for (mcnt = 1; mcnt < num_regs; mcnt++)
3770 best_regstart[mcnt] = regstart[mcnt];
3771 best_regend[mcnt] = regend[mcnt];
3777 /* If no failure points, don't restore garbage. And if
3778 last match is real best match, don't restore second
3780 else if (best_regs_set && !best_match_p)
3783 /* Restore best match. It may happen that `dend ==
3784 end_match_1' while the restored d is in string2.
3785 For example, the pattern `x.*y.*z' against the
3786 strings `x-' and `y-z-', if the two strings are
3787 not consecutive in memory. */
3788 DEBUG_PRINT1 ("Restoring best registers.\n");
3791 dend = ((d >= string1 && d <= end1)
3792 ? end_match_1 : end_match_2);
3794 for (mcnt = 1; mcnt < num_regs; mcnt++)
3796 regstart[mcnt] = best_regstart[mcnt];
3797 regend[mcnt] = best_regend[mcnt];
3800 } /* d != end_match_2 */
3803 DEBUG_PRINT1 ("Accepting match.\n");
3805 /* If caller wants register contents data back, do it. */
3806 if (regs && !bufp->no_sub)
3808 /* Have the register data arrays been allocated? */
3809 if (bufp->regs_allocated == REGS_UNALLOCATED)
3810 { /* No. So allocate them with malloc. We need one
3811 extra element beyond `num_regs' for the `-1' marker
3813 regs->num_regs = MAX (RE_NREGS, num_regs + 1);
3814 regs->start = TALLOC (regs->num_regs, regoff_t);
3815 regs->end = TALLOC (regs->num_regs, regoff_t);
3816 if (regs->start == NULL || regs->end == NULL)
3821 bufp->regs_allocated = REGS_REALLOCATE;
3823 else if (bufp->regs_allocated == REGS_REALLOCATE)
3824 { /* Yes. If we need more elements than were already
3825 allocated, reallocate them. If we need fewer, just
3827 if (regs->num_regs < num_regs + 1)
3829 regs->num_regs = num_regs + 1;
3830 RETALLOC (regs->start, regs->num_regs, regoff_t);
3831 RETALLOC (regs->end, regs->num_regs, regoff_t);
3832 if (regs->start == NULL || regs->end == NULL)
3841 /* These braces fend off a "empty body in an else-statement"
3842 warning under GCC when assert expands to nothing. */
3843 assert (bufp->regs_allocated == REGS_FIXED);
3846 /* Convert the pointer data in `regstart' and `regend' to
3847 indices. Register zero has to be set differently,
3848 since we haven't kept track of any info for it. */
3849 if (regs->num_regs > 0)
3851 regs->start[0] = pos;
3852 regs->end[0] = (MATCHING_IN_FIRST_STRING
3853 ? ((regoff_t) (d - string1))
3854 : ((regoff_t) (d - string2 + size1)));
3857 /* Go through the first `min (num_regs, regs->num_regs)'
3858 registers, since that is all we initialized. */
3859 for (mcnt = 1; mcnt < MIN (num_regs, regs->num_regs); mcnt++)
3861 if (REG_UNSET (regstart[mcnt]) || REG_UNSET (regend[mcnt]))
3862 regs->start[mcnt] = regs->end[mcnt] = -1;
3866 = (regoff_t) POINTER_TO_OFFSET (regstart[mcnt]);
3868 = (regoff_t) POINTER_TO_OFFSET (regend[mcnt]);
3872 /* If the regs structure we return has more elements than
3873 were in the pattern, set the extra elements to -1. If
3874 we (re)allocated the registers, this is the case,
3875 because we always allocate enough to have at least one
3877 for (mcnt = num_regs; mcnt < regs->num_regs; mcnt++)
3878 regs->start[mcnt] = regs->end[mcnt] = -1;
3879 } /* regs && !bufp->no_sub */
3881 DEBUG_PRINT4 ("%u failure points pushed, %u popped (%u remain).\n",
3882 nfailure_points_pushed, nfailure_points_popped,
3883 nfailure_points_pushed - nfailure_points_popped);
3884 DEBUG_PRINT2 ("%u registers pushed.\n", num_regs_pushed);
3886 mcnt = d - pos - (MATCHING_IN_FIRST_STRING
3890 DEBUG_PRINT2 ("Returning %d from re_match_2.\n", mcnt);
3896 /* Otherwise match next pattern command. */
3897 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
3899 /* Ignore these. Used to ignore the n of succeed_n's which
3900 currently have n == 0. */
3902 DEBUG_PRINT1 ("EXECUTING no_op.\n");
3906 DEBUG_PRINT1 ("EXECUTING succeed.\n");
3909 /* Match the next n pattern characters exactly. The following
3910 byte in the pattern defines n, and the n bytes after that
3911 are the characters to match. */
3914 DEBUG_PRINT2 ("EXECUTING exactn %d.\n", mcnt);
3916 /* This is written out as an if-else so we don't waste time
3917 testing `translate' inside the loop. */
3923 if (translate[(unsigned char) *d++] != (char) *p++)
3933 if (*d++ != (char) *p++) goto fail;
3937 SET_REGS_MATCHED ();
3941 /* Match any character except possibly a newline or a null. */
3943 DEBUG_PRINT1 ("EXECUTING anychar.\n");
3947 if ((!(bufp->syntax & RE_DOT_NEWLINE) && TRANSLATE (*d) == '\n')
3948 || (bufp->syntax & RE_DOT_NOT_NULL && TRANSLATE (*d) == '\000'))
3951 SET_REGS_MATCHED ();
3952 DEBUG_PRINT2 (" Matched `%d'.\n", *d);
3960 register unsigned char c;
3961 boolean not = (re_opcode_t) *(p - 1) == charset_not;
3963 DEBUG_PRINT2 ("EXECUTING charset%s.\n", not ? "_not" : "");
3966 c = TRANSLATE (*d); /* The character to match. */
3968 /* Cast to `unsigned' instead of `unsigned char' in case the
3969 bit list is a full 32 bytes long. */
3970 if (c < (unsigned) (*p * BYTEWIDTH)
3971 && p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
3976 if (!not) goto fail;
3978 SET_REGS_MATCHED ();
3984 /* The beginning of a group is represented by start_memory.
3985 The arguments are the register number in the next byte, and the
3986 number of groups inner to this one in the next. The text
3987 matched within the group is recorded (in the internal
3988 registers data structure) under the register number. */
3990 DEBUG_PRINT3 ("EXECUTING start_memory %d (%d):\n", *p, p[1]);
3992 /* Find out if this group can match the empty string. */
3993 p1 = p; /* To send to group_match_null_string_p. */
3995 if (REG_MATCH_NULL_STRING_P (reg_info[*p]) == MATCH_NULL_UNSET_VALUE)
3996 REG_MATCH_NULL_STRING_P (reg_info[*p])
3997 = group_match_null_string_p (&p1, pend, reg_info);
3999 /* Save the position in the string where we were the last time
4000 we were at this open-group operator in case the group is
4001 operated upon by a repetition operator, e.g., with `(a*)*b'
4002 against `ab'; then we want to ignore where we are now in
4003 the string in case this attempt to match fails. */
4004 old_regstart[*p] = REG_MATCH_NULL_STRING_P (reg_info[*p])
4005 ? REG_UNSET (regstart[*p]) ? d : regstart[*p]
4007 DEBUG_PRINT2 (" old_regstart: %d\n",
4008 POINTER_TO_OFFSET (old_regstart[*p]));
4011 DEBUG_PRINT2 (" regstart: %d\n", POINTER_TO_OFFSET (regstart[*p]));
4013 IS_ACTIVE (reg_info[*p]) = 1;
4014 MATCHED_SOMETHING (reg_info[*p]) = 0;
4016 /* Clear this whenever we change the register activity status. */
4017 set_regs_matched_done = 0;
4019 /* This is the new highest active register. */
4020 highest_active_reg = *p;
4022 /* If nothing was active before, this is the new lowest active
4024 if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
4025 lowest_active_reg = *p;
4027 /* Move past the register number and inner group count. */
4029 just_past_start_mem = p;
4034 /* The stop_memory opcode represents the end of a group. Its
4035 arguments are the same as start_memory's: the register
4036 number, and the number of inner groups. */
4038 DEBUG_PRINT3 ("EXECUTING stop_memory %d (%d):\n", *p, p[1]);
4040 /* We need to save the string position the last time we were at
4041 this close-group operator in case the group is operated
4042 upon by a repetition operator, e.g., with `((a*)*(b*)*)*'
4043 against `aba'; then we want to ignore where we are now in
4044 the string in case this attempt to match fails. */
4045 old_regend[*p] = REG_MATCH_NULL_STRING_P (reg_info[*p])
4046 ? REG_UNSET (regend[*p]) ? d : regend[*p]
4048 DEBUG_PRINT2 (" old_regend: %d\n",
4049 POINTER_TO_OFFSET (old_regend[*p]));
4052 DEBUG_PRINT2 (" regend: %d\n", POINTER_TO_OFFSET (regend[*p]));
4054 /* This register isn't active anymore. */
4055 IS_ACTIVE (reg_info[*p]) = 0;
4057 /* Clear this whenever we change the register activity status. */
4058 set_regs_matched_done = 0;
4060 /* If this was the only register active, nothing is active
4062 if (lowest_active_reg == highest_active_reg)
4064 lowest_active_reg = NO_LOWEST_ACTIVE_REG;
4065 highest_active_reg = NO_HIGHEST_ACTIVE_REG;
4068 { /* We must scan for the new highest active register, since
4069 it isn't necessarily one less than now: consider
4070 (a(b)c(d(e)f)g). When group 3 ends, after the f), the
4071 new highest active register is 1. */
4072 unsigned char r = *p - 1;
4073 while (r > 0 && !IS_ACTIVE (reg_info[r]))
4076 /* If we end up at register zero, that means that we saved
4077 the registers as the result of an `on_failure_jump', not
4078 a `start_memory', and we jumped to past the innermost
4079 `stop_memory'. For example, in ((.)*) we save
4080 registers 1 and 2 as a result of the *, but when we pop
4081 back to the second ), we are at the stop_memory 1.
4082 Thus, nothing is active. */
4085 lowest_active_reg = NO_LOWEST_ACTIVE_REG;
4086 highest_active_reg = NO_HIGHEST_ACTIVE_REG;
4089 highest_active_reg = r;
4092 /* If just failed to match something this time around with a
4093 group that's operated on by a repetition operator, try to
4094 force exit from the ``loop'', and restore the register
4095 information for this group that we had before trying this
4097 if ((!MATCHED_SOMETHING (reg_info[*p])
4098 || just_past_start_mem == p - 1)
4101 boolean is_a_jump_n = false;
4105 switch ((re_opcode_t) *p1++)
4109 case pop_failure_jump:
4110 case maybe_pop_jump:
4112 case dummy_failure_jump:
4113 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4123 /* If the next operation is a jump backwards in the pattern
4124 to an on_failure_jump right before the start_memory
4125 corresponding to this stop_memory, exit from the loop
4126 by forcing a failure after pushing on the stack the
4127 on_failure_jump's jump in the pattern, and d. */
4128 if (mcnt < 0 && (re_opcode_t) *p1 == on_failure_jump
4129 && (re_opcode_t) p1[3] == start_memory && p1[4] == *p)
4131 /* If this group ever matched anything, then restore
4132 what its registers were before trying this last
4133 failed match, e.g., with `(a*)*b' against `ab' for
4134 regstart[1], and, e.g., with `((a*)*(b*)*)*'
4135 against `aba' for regend[3].
4137 Also restore the registers for inner groups for,
4138 e.g., `((a*)(b*))*' against `aba' (register 3 would
4139 otherwise get trashed). */
4141 if (EVER_MATCHED_SOMETHING (reg_info[*p]))
4145 EVER_MATCHED_SOMETHING (reg_info[*p]) = 0;
4147 /* Restore this and inner groups' (if any) registers. */
4148 for (r = *p; r < *p + *(p + 1); r++)
4150 regstart[r] = old_regstart[r];
4152 /* xx why this test? */
4153 if (old_regend[r] >= regstart[r])
4154 regend[r] = old_regend[r];
4158 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4159 PUSH_FAILURE_POINT (p1 + mcnt, d, -2);
4165 /* Move past the register number and the inner group count. */
4170 /* \<digit> has been turned into a `duplicate' command which is
4171 followed by the numeric value of <digit> as the register number. */
4174 register const char *d2, *dend2;
4175 int regno = *p++; /* Get which register to match against. */
4176 DEBUG_PRINT2 ("EXECUTING duplicate %d.\n", regno);
4178 /* Can't back reference a group which we've never matched. */
4179 if (REG_UNSET (regstart[regno]) || REG_UNSET (regend[regno]))
4182 /* Where in input to try to start matching. */
4183 d2 = regstart[regno];
4185 /* Where to stop matching; if both the place to start and
4186 the place to stop matching are in the same string, then
4187 set to the place to stop, otherwise, for now have to use
4188 the end of the first string. */
4190 dend2 = ((FIRST_STRING_P (regstart[regno])
4191 == FIRST_STRING_P (regend[regno]))
4192 ? regend[regno] : end_match_1);
4195 /* If necessary, advance to next segment in register
4199 if (dend2 == end_match_2) break;
4200 if (dend2 == regend[regno]) break;
4202 /* End of string1 => advance to string2. */
4204 dend2 = regend[regno];
4206 /* At end of register contents => success */
4207 if (d2 == dend2) break;
4209 /* If necessary, advance to next segment in data. */
4212 /* How many characters left in this segment to match. */
4215 /* Want how many consecutive characters we can match in
4216 one shot, so, if necessary, adjust the count. */
4217 if (mcnt > dend2 - d2)
4220 /* Compare that many; failure if mismatch, else move
4223 ? bcmp_translate (d, d2, mcnt, translate)
4224 : bcmp (d, d2, mcnt))
4226 d += mcnt, d2 += mcnt;
4228 /* Do this because we've match some characters. */
4229 SET_REGS_MATCHED ();
4235 /* begline matches the empty string at the beginning of the string
4236 (unless `not_bol' is set in `bufp'), and, if
4237 `newline_anchor' is set, after newlines. */
4239 DEBUG_PRINT1 ("EXECUTING begline.\n");
4241 if (AT_STRINGS_BEG (d))
4243 if (!bufp->not_bol) break;
4245 else if (d[-1] == '\n' && bufp->newline_anchor)
4249 /* In all other cases, we fail. */
4253 /* endline is the dual of begline. */
4255 DEBUG_PRINT1 ("EXECUTING endline.\n");
4257 if (AT_STRINGS_END (d))
4259 if (!bufp->not_eol) break;
4262 /* We have to ``prefetch'' the next character. */
4263 else if ((d == end1 ? *string2 : *d) == '\n'
4264 && bufp->newline_anchor)
4271 /* Match at the very beginning of the data. */
4273 DEBUG_PRINT1 ("EXECUTING begbuf.\n");
4274 if (AT_STRINGS_BEG (d))
4279 /* Match at the very end of the data. */
4281 DEBUG_PRINT1 ("EXECUTING endbuf.\n");
4282 if (AT_STRINGS_END (d))
4287 /* on_failure_keep_string_jump is used to optimize `.*\n'. It
4288 pushes NULL as the value for the string on the stack. Then
4289 `pop_failure_point' will keep the current value for the
4290 string, instead of restoring it. To see why, consider
4291 matching `foo\nbar' against `.*\n'. The .* matches the foo;
4292 then the . fails against the \n. But the next thing we want
4293 to do is match the \n against the \n; if we restored the
4294 string value, we would be back at the foo.
4296 Because this is used only in specific cases, we don't need to
4297 check all the things that `on_failure_jump' does, to make
4298 sure the right things get saved on the stack. Hence we don't
4299 share its code. The only reason to push anything on the
4300 stack at all is that otherwise we would have to change
4301 `anychar's code to do something besides goto fail in this
4302 case; that seems worse than this. */
4303 case on_failure_keep_string_jump:
4304 DEBUG_PRINT1 ("EXECUTING on_failure_keep_string_jump");
4306 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4307 DEBUG_PRINT3 (" %d (to 0x%x):\n", mcnt, p + mcnt);
4309 PUSH_FAILURE_POINT (p + mcnt, NULL, -2);
4313 /* Uses of on_failure_jump:
4315 Each alternative starts with an on_failure_jump that points
4316 to the beginning of the next alternative. Each alternative
4317 except the last ends with a jump that in effect jumps past
4318 the rest of the alternatives. (They really jump to the
4319 ending jump of the following alternative, because tensioning
4320 these jumps is a hassle.)
4322 Repeats start with an on_failure_jump that points past both
4323 the repetition text and either the following jump or
4324 pop_failure_jump back to this on_failure_jump. */
4325 case on_failure_jump:
4327 DEBUG_PRINT1 ("EXECUTING on_failure_jump");
4329 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4330 DEBUG_PRINT3 (" %d (to 0x%x)", mcnt, p + mcnt);
4332 /* If this on_failure_jump comes right before a group (i.e.,
4333 the original * applied to a group), save the information
4334 for that group and all inner ones, so that if we fail back
4335 to this point, the group's information will be correct.
4336 For example, in \(a*\)*\1, we need the preceding group,
4337 and in \(\(a*\)b*\)\2, we need the inner group. */
4339 /* We can't use `p' to check ahead because we push
4340 a failure point to `p + mcnt' after we do this. */
4343 /* We need to skip no_op's before we look for the
4344 start_memory in case this on_failure_jump is happening as
4345 the result of a completed succeed_n, as in \(a\)\{1,3\}b\1
4347 while (p1 < pend && (re_opcode_t) *p1 == no_op)
4350 if (p1 < pend && (re_opcode_t) *p1 == start_memory)
4352 /* We have a new highest active register now. This will
4353 get reset at the start_memory we are about to get to,
4354 but we will have saved all the registers relevant to
4355 this repetition op, as described above. */
4356 highest_active_reg = *(p1 + 1) + *(p1 + 2);
4357 if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
4358 lowest_active_reg = *(p1 + 1);
4361 DEBUG_PRINT1 (":\n");
4362 PUSH_FAILURE_POINT (p + mcnt, d, -2);
4366 /* A smart repeat ends with `maybe_pop_jump'.
4367 We change it to either `pop_failure_jump' or `jump'. */
4368 case maybe_pop_jump:
4369 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4370 DEBUG_PRINT2 ("EXECUTING maybe_pop_jump %d.\n", mcnt);
4372 register unsigned char *p2 = p;
4374 /* Compare the beginning of the repeat with what in the
4375 pattern follows its end. If we can establish that there
4376 is nothing that they would both match, i.e., that we
4377 would have to backtrack because of (as in, e.g., `a*a')
4378 then we can change to pop_failure_jump, because we'll
4379 never have to backtrack.
4381 This is not true in the case of alternatives: in
4382 `(a|ab)*' we do need to backtrack to the `ab' alternative
4383 (e.g., if the string was `ab'). But instead of trying to
4384 detect that here, the alternative has put on a dummy
4385 failure point which is what we will end up popping. */
4387 /* Skip over open/close-group commands.
4388 If what follows this loop is a ...+ construct,
4389 look at what begins its body, since we will have to
4390 match at least one of that. */
4394 && ((re_opcode_t) *p2 == stop_memory
4395 || (re_opcode_t) *p2 == start_memory))
4397 else if (p2 + 6 < pend
4398 && (re_opcode_t) *p2 == dummy_failure_jump)
4405 /* p1[0] ... p1[2] are the `on_failure_jump' corresponding
4406 to the `maybe_finalize_jump' of this case. Examine what
4409 /* If we're at the end of the pattern, we can change. */
4412 /* Consider what happens when matching ":\(.*\)"
4413 against ":/". I don't really understand this code
4415 p[-3] = (unsigned char) pop_failure_jump;
4417 (" End of pattern: change to `pop_failure_jump'.\n");
4420 else if ((re_opcode_t) *p2 == exactn
4421 || (bufp->newline_anchor && (re_opcode_t) *p2 == endline))
4423 register unsigned char c
4424 = *p2 == (unsigned char) endline ? '\n' : p2[2];
4426 if ((re_opcode_t) p1[3] == exactn && p1[5] != c)
4428 p[-3] = (unsigned char) pop_failure_jump;
4429 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n",
4433 else if ((re_opcode_t) p1[3] == charset
4434 || (re_opcode_t) p1[3] == charset_not)
4436 int not = (re_opcode_t) p1[3] == charset_not;
4438 if (c < (unsigned char) (p1[4] * BYTEWIDTH)
4439 && p1[5 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4442 /* `not' is equal to 1 if c would match, which means
4443 that we can't change to pop_failure_jump. */
4446 p[-3] = (unsigned char) pop_failure_jump;
4447 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4451 else if ((re_opcode_t) *p2 == charset)
4454 register unsigned char c
4455 = *p2 == (unsigned char) endline ? '\n' : p2[2];
4458 if ((re_opcode_t) p1[3] == exactn
4459 && ! ((int) p2[1] * BYTEWIDTH > (int) p1[4]
4460 && (p2[1 + p1[4] / BYTEWIDTH]
4461 & (1 << (p1[4] % BYTEWIDTH)))))
4463 p[-3] = (unsigned char) pop_failure_jump;
4464 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n",
4468 else if ((re_opcode_t) p1[3] == charset_not)
4471 /* We win if the charset_not inside the loop
4472 lists every character listed in the charset after. */
4473 for (idx = 0; idx < (int) p2[1]; idx++)
4474 if (! (p2[2 + idx] == 0
4475 || (idx < (int) p1[4]
4476 && ((p2[2 + idx] & ~ p1[5 + idx]) == 0))))
4481 p[-3] = (unsigned char) pop_failure_jump;
4482 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4485 else if ((re_opcode_t) p1[3] == charset)
4488 /* We win if the charset inside the loop
4489 has no overlap with the one after the loop. */
4491 idx < (int) p2[1] && idx < (int) p1[4];
4493 if ((p2[2 + idx] & p1[5 + idx]) != 0)
4496 if (idx == p2[1] || idx == p1[4])
4498 p[-3] = (unsigned char) pop_failure_jump;
4499 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4504 p -= 2; /* Point at relative address again. */
4505 if ((re_opcode_t) p[-1] != pop_failure_jump)
4507 p[-1] = (unsigned char) jump;
4508 DEBUG_PRINT1 (" Match => jump.\n");
4509 goto unconditional_jump;
4511 /* Note fall through. */
4514 /* The end of a simple repeat has a pop_failure_jump back to
4515 its matching on_failure_jump, where the latter will push a
4516 failure point. The pop_failure_jump takes off failure
4517 points put on by this pop_failure_jump's matching
4518 on_failure_jump; we got through the pattern to here from the
4519 matching on_failure_jump, so didn't fail. */
4520 case pop_failure_jump:
4522 /* We need to pass separate storage for the lowest and
4523 highest registers, even though we don't care about the
4524 actual values. Otherwise, we will restore only one
4525 register from the stack, since lowest will == highest in
4526 `pop_failure_point'. */
4527 unsigned dummy_low_reg, dummy_high_reg;
4528 unsigned char *pdummy;
4531 DEBUG_PRINT1 ("EXECUTING pop_failure_jump.\n");
4532 POP_FAILURE_POINT (sdummy, pdummy,
4533 dummy_low_reg, dummy_high_reg,
4534 reg_dummy, reg_dummy, reg_info_dummy);
4536 /* Note fall through. */
4539 /* Unconditionally jump (without popping any failure points). */
4542 EXTRACT_NUMBER_AND_INCR (mcnt, p); /* Get the amount to jump. */
4543 DEBUG_PRINT2 ("EXECUTING jump %d ", mcnt);
4544 p += mcnt; /* Do the jump. */
4545 DEBUG_PRINT2 ("(to 0x%x).\n", p);
4549 /* We need this opcode so we can detect where alternatives end
4550 in `group_match_null_string_p' et al. */
4552 DEBUG_PRINT1 ("EXECUTING jump_past_alt.\n");
4553 goto unconditional_jump;
4556 /* Normally, the on_failure_jump pushes a failure point, which
4557 then gets popped at pop_failure_jump. We will end up at
4558 pop_failure_jump, also, and with a pattern of, say, `a+', we
4559 are skipping over the on_failure_jump, so we have to push
4560 something meaningless for pop_failure_jump to pop. */
4561 case dummy_failure_jump:
4562 DEBUG_PRINT1 ("EXECUTING dummy_failure_jump.\n");
4563 /* It doesn't matter what we push for the string here. What
4564 the code at `fail' tests is the value for the pattern. */
4565 PUSH_FAILURE_POINT (0, 0, -2);
4566 goto unconditional_jump;
4569 /* At the end of an alternative, we need to push a dummy failure
4570 point in case we are followed by a `pop_failure_jump', because
4571 we don't want the failure point for the alternative to be
4572 popped. For example, matching `(a|ab)*' against `aab'
4573 requires that we match the `ab' alternative. */
4574 case push_dummy_failure:
4575 DEBUG_PRINT1 ("EXECUTING push_dummy_failure.\n");
4576 /* See comments just above at `dummy_failure_jump' about the
4578 PUSH_FAILURE_POINT (0, 0, -2);
4581 /* Have to succeed matching what follows at least n times.
4582 After that, handle like `on_failure_jump'. */
4584 EXTRACT_NUMBER (mcnt, p + 2);
4585 DEBUG_PRINT2 ("EXECUTING succeed_n %d.\n", mcnt);
4588 /* Originally, this is how many times we HAVE to succeed. */
4593 STORE_NUMBER_AND_INCR (p, mcnt);
4594 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p, mcnt);
4598 DEBUG_PRINT2 (" Setting two bytes from 0x%x to no_op.\n", p+2);
4599 p[2] = (unsigned char) no_op;
4600 p[3] = (unsigned char) no_op;
4606 EXTRACT_NUMBER (mcnt, p + 2);
4607 DEBUG_PRINT2 ("EXECUTING jump_n %d.\n", mcnt);
4609 /* Originally, this is how many times we CAN jump. */
4613 STORE_NUMBER (p + 2, mcnt);
4614 goto unconditional_jump;
4616 /* If don't have to jump any more, skip over the rest of command. */
4623 DEBUG_PRINT1 ("EXECUTING set_number_at.\n");
4625 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4627 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4628 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p1, mcnt);
4629 STORE_NUMBER (p1, mcnt);
4634 DEBUG_PRINT1 ("EXECUTING wordbound.\n");
4635 if (AT_WORD_BOUNDARY (d))
4640 DEBUG_PRINT1 ("EXECUTING notwordbound.\n");
4641 if (AT_WORD_BOUNDARY (d))
4646 DEBUG_PRINT1 ("EXECUTING wordbeg.\n");
4647 if (WORDCHAR_P (d) && (AT_STRINGS_BEG (d) || !WORDCHAR_P (d - 1)))
4652 DEBUG_PRINT1 ("EXECUTING wordend.\n");
4653 if (!AT_STRINGS_BEG (d) && WORDCHAR_P (d - 1)
4654 && (!WORDCHAR_P (d) || AT_STRINGS_END (d)))
4660 DEBUG_PRINT1 ("EXECUTING before_dot.\n");
4661 if (PTR_CHAR_POS ((unsigned char *) d) >= point)
4666 DEBUG_PRINT1 ("EXECUTING at_dot.\n");
4667 if (PTR_CHAR_POS ((unsigned char *) d) != point)
4672 DEBUG_PRINT1 ("EXECUTING after_dot.\n");
4673 if (PTR_CHAR_POS ((unsigned char *) d) <= point)
4676 #if 0 /* not emacs19 */
4678 DEBUG_PRINT1 ("EXECUTING at_dot.\n");
4679 if (PTR_CHAR_POS ((unsigned char *) d) + 1 != point)
4682 #endif /* not emacs19 */
4685 DEBUG_PRINT2 ("EXECUTING syntaxspec %d.\n", mcnt);
4690 DEBUG_PRINT1 ("EXECUTING Emacs wordchar.\n");
4694 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
4696 if (SYNTAX (d[-1]) != (enum syntaxcode) mcnt)
4698 SET_REGS_MATCHED ();
4702 DEBUG_PRINT2 ("EXECUTING notsyntaxspec %d.\n", mcnt);
4704 goto matchnotsyntax;
4707 DEBUG_PRINT1 ("EXECUTING Emacs notwordchar.\n");
4711 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
4713 if (SYNTAX (d[-1]) == (enum syntaxcode) mcnt)
4715 SET_REGS_MATCHED ();
4718 #else /* not emacs */
4720 DEBUG_PRINT1 ("EXECUTING non-Emacs wordchar.\n");
4722 if (!WORDCHAR_P (d))
4724 SET_REGS_MATCHED ();
4729 DEBUG_PRINT1 ("EXECUTING non-Emacs notwordchar.\n");
4733 SET_REGS_MATCHED ();
4736 #endif /* not emacs */
4741 continue; /* Successfully executed one pattern command; keep going. */
4744 /* We goto here if a matching operation fails. */
4746 if (!FAIL_STACK_EMPTY ())
4747 { /* A restart point is known. Restore to that state. */
4748 DEBUG_PRINT1 ("\nFAIL:\n");
4749 POP_FAILURE_POINT (d, p,
4750 lowest_active_reg, highest_active_reg,
4751 regstart, regend, reg_info);
4753 /* If this failure point is a dummy, try the next one. */
4757 /* If we failed to the end of the pattern, don't examine *p. */
4761 boolean is_a_jump_n = false;
4763 /* If failed to a backwards jump that's part of a repetition
4764 loop, need to pop this failure point and use the next one. */
4765 switch ((re_opcode_t) *p)
4769 case maybe_pop_jump:
4770 case pop_failure_jump:
4773 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4776 if ((is_a_jump_n && (re_opcode_t) *p1 == succeed_n)
4778 && (re_opcode_t) *p1 == on_failure_jump))
4786 if (d >= string1 && d <= end1)
4790 break; /* Matching at this starting point really fails. */
4794 goto restore_best_regs;
4798 return -1; /* Failure to match. */
4801 /* Subroutine definitions for re_match_2. */
4804 /* We are passed P pointing to a register number after a start_memory.
4806 Return true if the pattern up to the corresponding stop_memory can
4807 match the empty string, and false otherwise.
4809 If we find the matching stop_memory, sets P to point to one past its number.
4810 Otherwise, sets P to an undefined byte less than or equal to END.
4812 We don't handle duplicates properly (yet). */
4815 group_match_null_string_p (p, end, reg_info)
4816 unsigned char **p, *end;
4817 register_info_type *reg_info;
4820 /* Point to after the args to the start_memory. */
4821 unsigned char *p1 = *p + 2;
4825 /* Skip over opcodes that can match nothing, and return true or
4826 false, as appropriate, when we get to one that can't, or to the
4827 matching stop_memory. */
4829 switch ((re_opcode_t) *p1)
4831 /* Could be either a loop or a series of alternatives. */
4832 case on_failure_jump:
4834 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4836 /* If the next operation is not a jump backwards in the
4841 /* Go through the on_failure_jumps of the alternatives,
4842 seeing if any of the alternatives cannot match nothing.
4843 The last alternative starts with only a jump,
4844 whereas the rest start with on_failure_jump and end
4845 with a jump, e.g., here is the pattern for `a|b|c':
4847 /on_failure_jump/0/6/exactn/1/a/jump_past_alt/0/6
4848 /on_failure_jump/0/6/exactn/1/b/jump_past_alt/0/3
4851 So, we have to first go through the first (n-1)
4852 alternatives and then deal with the last one separately. */
4855 /* Deal with the first (n-1) alternatives, which start
4856 with an on_failure_jump (see above) that jumps to right
4857 past a jump_past_alt. */
4859 while ((re_opcode_t) p1[mcnt-3] == jump_past_alt)
4861 /* `mcnt' holds how many bytes long the alternative
4862 is, including the ending `jump_past_alt' and
4865 if (!alt_match_null_string_p (p1, p1 + mcnt - 3,
4869 /* Move to right after this alternative, including the
4873 /* Break if it's the beginning of an n-th alternative
4874 that doesn't begin with an on_failure_jump. */
4875 if ((re_opcode_t) *p1 != on_failure_jump)
4878 /* Still have to check that it's not an n-th
4879 alternative that starts with an on_failure_jump. */
4881 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4882 if ((re_opcode_t) p1[mcnt-3] != jump_past_alt)
4884 /* Get to the beginning of the n-th alternative. */
4890 /* Deal with the last alternative: go back and get number
4891 of the `jump_past_alt' just before it. `mcnt' contains
4892 the length of the alternative. */
4893 EXTRACT_NUMBER (mcnt, p1 - 2);
4895 if (!alt_match_null_string_p (p1, p1 + mcnt, reg_info))
4898 p1 += mcnt; /* Get past the n-th alternative. */
4904 assert (p1[1] == **p);
4910 if (!common_op_match_null_string_p (&p1, end, reg_info))
4913 } /* while p1 < end */
4916 } /* group_match_null_string_p */
4919 /* Similar to group_match_null_string_p, but doesn't deal with alternatives:
4920 It expects P to be the first byte of a single alternative and END one
4921 byte past the last. The alternative can contain groups. */
4924 alt_match_null_string_p (p, end, reg_info)
4925 unsigned char *p, *end;
4926 register_info_type *reg_info;
4929 unsigned char *p1 = p;
4933 /* Skip over opcodes that can match nothing, and break when we get
4934 to one that can't. */
4936 switch ((re_opcode_t) *p1)
4939 case on_failure_jump:
4941 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4946 if (!common_op_match_null_string_p (&p1, end, reg_info))
4949 } /* while p1 < end */
4952 } /* alt_match_null_string_p */
4955 /* Deals with the ops common to group_match_null_string_p and
4956 alt_match_null_string_p.
4958 Sets P to one after the op and its arguments, if any. */
4961 common_op_match_null_string_p (p, end, reg_info)
4962 unsigned char **p, *end;
4963 register_info_type *reg_info;
4968 unsigned char *p1 = *p;
4970 switch ((re_opcode_t) *p1++)
4990 assert (reg_no > 0 && reg_no <= MAX_REGNUM);
4991 ret = group_match_null_string_p (&p1, end, reg_info);
4993 /* Have to set this here in case we're checking a group which
4994 contains a group and a back reference to it. */
4996 if (REG_MATCH_NULL_STRING_P (reg_info[reg_no]) == MATCH_NULL_UNSET_VALUE)
4997 REG_MATCH_NULL_STRING_P (reg_info[reg_no]) = ret;
5003 /* If this is an optimized succeed_n for zero times, make the jump. */
5005 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5013 /* Get to the number of times to succeed. */
5015 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5020 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5028 if (!REG_MATCH_NULL_STRING_P (reg_info[*p1]))
5036 /* All other opcodes mean we cannot match the empty string. */
5042 } /* common_op_match_null_string_p */
5045 /* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
5046 bytes; nonzero otherwise. */
5049 bcmp_translate (s1, s2, len, translate)
5050 unsigned char *s1, *s2;
5054 register unsigned char *p1 = s1, *p2 = s2;
5057 if (translate[*p1++] != translate[*p2++]) return 1;
5063 /* Entry points for GNU code. */
5065 /* re_compile_pattern is the GNU regular expression compiler: it
5066 compiles PATTERN (of length SIZE) and puts the result in BUFP.
5067 Returns 0 if the pattern was valid, otherwise an error string.
5069 Assumes the `allocated' (and perhaps `buffer') and `translate' fields
5070 are set in BUFP on entry.
5072 We call regex_compile to do the actual compilation. */
5075 re_compile_pattern (pattern, length, bufp)
5076 const char *pattern;
5078 struct re_pattern_buffer *bufp;
5082 /* GNU code is written to assume at least RE_NREGS registers will be set
5083 (and at least one extra will be -1). */
5084 bufp->regs_allocated = REGS_UNALLOCATED;
5086 /* And GNU code determines whether or not to get register information
5087 by passing null for the REGS argument to re_match, etc., not by
5091 /* Match anchors at newline. */
5092 bufp->newline_anchor = 1;
5094 ret = regex_compile (pattern, length, re_syntax_options, bufp);
5098 return gettext (re_error_msgid[(int) ret]);
5101 /* Entry points compatible with 4.2 BSD regex library. We don't define
5102 them unless specifically requested. */
5104 #ifdef _REGEX_RE_COMP
5106 /* BSD has one and only one pattern buffer. */
5107 static struct re_pattern_buffer re_comp_buf;
5117 if (!re_comp_buf.buffer)
5118 return gettext ("No previous regular expression");
5122 if (!re_comp_buf.buffer)
5124 re_comp_buf.buffer = (unsigned char *) malloc (200);
5125 if (re_comp_buf.buffer == NULL)
5126 return gettext (re_error_msgid[(int) REG_ESPACE]);
5127 re_comp_buf.allocated = 200;
5129 re_comp_buf.fastmap = (char *) malloc (1 << BYTEWIDTH);
5130 if (re_comp_buf.fastmap == NULL)
5131 return gettext (re_error_msgid[(int) REG_ESPACE]);
5134 /* Since `re_exec' always passes NULL for the `regs' argument, we
5135 don't need to initialize the pattern buffer fields which affect it. */
5137 /* Match anchors at newlines. */
5138 re_comp_buf.newline_anchor = 1;
5140 ret = regex_compile (s, strlen (s), re_syntax_options, &re_comp_buf);
5145 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
5146 return (char *) gettext (re_error_msgid[(int) ret]);
5154 const int len = strlen (s);
5156 0 <= re_search (&re_comp_buf, s, len, 0, len, (struct re_registers *) 0);
5158 #endif /* _REGEX_RE_COMP */
5160 /* POSIX.2 functions. Don't define these for Emacs. */
5164 /* regcomp takes a regular expression as a string and compiles it.
5166 PREG is a regex_t *. We do not expect any fields to be initialized,
5167 since POSIX says we shouldn't. Thus, we set
5169 `buffer' to the compiled pattern;
5170 `used' to the length of the compiled pattern;
5171 `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
5172 REG_EXTENDED bit in CFLAGS is set; otherwise, to
5173 RE_SYNTAX_POSIX_BASIC;
5174 `newline_anchor' to REG_NEWLINE being set in CFLAGS;
5175 `fastmap' and `fastmap_accurate' to zero;
5176 `re_nsub' to the number of subexpressions in PATTERN.
5178 PATTERN is the address of the pattern string.
5180 CFLAGS is a series of bits which affect compilation.
5182 If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
5183 use POSIX basic syntax.
5185 If REG_NEWLINE is set, then . and [^...] don't match newline.
5186 Also, regexec will try a match beginning after every newline.
5188 If REG_ICASE is set, then we considers upper- and lowercase
5189 versions of letters to be equivalent when matching.
5191 If REG_NOSUB is set, then when PREG is passed to regexec, that
5192 routine will report only success or failure, and nothing about the
5195 It returns 0 if it succeeds, nonzero if it doesn't. (See regex.h for
5196 the return codes and their meanings.) */
5199 regcomp (preg, pattern, cflags)
5201 const char *pattern;
5206 = (cflags & REG_EXTENDED) ?
5207 RE_SYNTAX_POSIX_EXTENDED : RE_SYNTAX_POSIX_BASIC;
5209 /* regex_compile will allocate the space for the compiled pattern. */
5211 preg->allocated = 0;
5214 /* Don't bother to use a fastmap when searching. This simplifies the
5215 REG_NEWLINE case: if we used a fastmap, we'd have to put all the
5216 characters after newlines into the fastmap. This way, we just try
5220 if (cflags & REG_ICASE)
5224 preg->translate = (char *) malloc (CHAR_SET_SIZE);
5225 if (preg->translate == NULL)
5226 return (int) REG_ESPACE;
5228 /* Map uppercase characters to corresponding lowercase ones. */
5229 for (i = 0; i < CHAR_SET_SIZE; i++)
5230 preg->translate[i] = ISUPPER (i) ? tolower (i) : i;
5233 preg->translate = NULL;
5235 /* If REG_NEWLINE is set, newlines are treated differently. */
5236 if (cflags & REG_NEWLINE)
5237 { /* REG_NEWLINE implies neither . nor [^...] match newline. */
5238 syntax &= ~RE_DOT_NEWLINE;
5239 syntax |= RE_HAT_LISTS_NOT_NEWLINE;
5240 /* It also changes the matching behavior. */
5241 preg->newline_anchor = 1;
5244 preg->newline_anchor = 0;
5246 preg->no_sub = !!(cflags & REG_NOSUB);
5248 /* POSIX says a null character in the pattern terminates it, so we
5249 can use strlen here in compiling the pattern. */
5250 ret = regex_compile (pattern, strlen (pattern), syntax, preg);
5252 /* POSIX doesn't distinguish between an unmatched open-group and an
5253 unmatched close-group: both are REG_EPAREN. */
5254 if (ret == REG_ERPAREN) ret = REG_EPAREN;
5260 /* regexec searches for a given pattern, specified by PREG, in the
5263 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
5264 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
5265 least NMATCH elements, and we set them to the offsets of the
5266 corresponding matched substrings.
5268 EFLAGS specifies `execution flags' which affect matching: if
5269 REG_NOTBOL is set, then ^ does not match at the beginning of the
5270 string; if REG_NOTEOL is set, then $ does not match at the end.
5272 We return 0 if we find a match and REG_NOMATCH if not. */
5275 regexec (preg, string, nmatch, pmatch, eflags)
5276 const regex_t *preg;
5279 regmatch_t pmatch[];
5283 struct re_registers regs;
5284 regex_t private_preg;
5285 int len = strlen (string);
5286 boolean want_reg_info = !preg->no_sub && nmatch > 0;
5288 private_preg = *preg;
5290 private_preg.not_bol = !!(eflags & REG_NOTBOL);
5291 private_preg.not_eol = !!(eflags & REG_NOTEOL);
5293 /* The user has told us exactly how many registers to return
5294 information about, via `nmatch'. We have to pass that on to the
5295 matching routines. */
5296 private_preg.regs_allocated = REGS_FIXED;
5300 regs.num_regs = nmatch;
5301 regs.start = TALLOC (nmatch, regoff_t);
5302 regs.end = TALLOC (nmatch, regoff_t);
5303 if (regs.start == NULL || regs.end == NULL)
5304 return (int) REG_NOMATCH;
5307 /* Perform the searching operation. */
5308 ret = re_search (&private_preg, string, len,
5309 /* start: */ 0, /* range: */ len,
5310 want_reg_info ? ®s : (struct re_registers *) 0);
5312 /* Copy the register information to the POSIX structure. */
5319 for (r = 0; r < nmatch; r++)
5321 pmatch[r].rm_so = regs.start[r];
5322 pmatch[r].rm_eo = regs.end[r];
5326 /* If we needed the temporary register info, free the space now. */
5331 /* We want zero return to mean success, unlike `re_search'. */
5332 return ret >= 0 ? (int) REG_NOERROR : (int) REG_NOMATCH;
5336 /* Returns a message corresponding to an error code, ERRCODE, returned
5337 from either regcomp or regexec. We don't use PREG here. */
5340 regerror (errcode, preg, errbuf, errbuf_size)
5342 const regex_t *preg;
5350 || errcode >= (sizeof (re_error_msgid) / sizeof (re_error_msgid[0])))
5351 /* Only error codes returned by the rest of the code should be passed
5352 to this routine. If we are given anything else, or if other regex
5353 code generates an invalid error code, then the program has a bug.
5354 Dump core so we can fix it. */
5357 msg = gettext (re_error_msgid[errcode]);
5359 msg_size = strlen (msg) + 1; /* Includes the null. */
5361 if (errbuf_size != 0)
5363 if (msg_size > errbuf_size)
5365 strncpy (errbuf, msg, errbuf_size - 1);
5366 errbuf[errbuf_size - 1] = 0;
5369 strcpy (errbuf, msg);
5376 /* Free dynamically allocated space used by PREG. */
5382 if (preg->buffer != NULL)
5383 free (preg->buffer);
5384 preg->buffer = NULL;
5386 preg->allocated = 0;
5389 if (preg->fastmap != NULL)
5390 free (preg->fastmap);
5391 preg->fastmap = NULL;
5392 preg->fastmap_accurate = 0;
5394 if (preg->translate != NULL)
5395 free (preg->translate);
5396 preg->translate = NULL;
5399 #endif /* not emacs */
5403 make-backup-files: t
5405 trim-versions-without-asking: nil