1 /* Extended regular expression matching and search library,
3 (Implements POSIX draft P10003.2/D11.2, except for
4 internationalization features.)
6 Copyright (C) 1993, 1994, 1995 Free Software Foundation, Inc.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
22 /* AIX requires this to be the first thing in the file. */
23 #if defined (_AIX) && !defined (REGEX_MALLOC)
33 /* We need this for `regex.h', and perhaps for the Emacs include files. */
34 #include <sys/types.h>
36 /* This is for other GNU distributions with internationalized messages. */
37 #if HAVE_LIBINTL_H || defined (_LIBC)
40 # define gettext(msgid) (msgid)
43 /* The `emacs' switch turns on certain matching commands
44 that make sense only in Emacs. */
53 /* If we are not linking with Emacs proper,
54 we can't use the relocating allocator
55 even if config.h says that we can. */
58 #if defined (STDC_HEADERS) || defined (_LIBC)
65 /* When used in Emacs's lib-src, we need to get bzero and bcopy somehow.
66 If nothing else has been done, use the method below. */
67 #ifdef INHIBIT_STRING_HEADER
68 #if !(defined (HAVE_BZERO) && defined (HAVE_BCOPY))
69 #if !defined (bzero) && !defined (bcopy)
70 #undef INHIBIT_STRING_HEADER
75 /* This is the normal way of making sure we have a bcopy and a bzero.
76 This is used in most programs--a few other programs avoid this
77 by defining INHIBIT_STRING_HEADER. */
78 #ifndef INHIBIT_STRING_HEADER
79 #if defined (HAVE_STRING_H) || defined (STDC_HEADERS) || defined (_LIBC)
82 #define bcmp(s1, s2, n) memcmp ((s1), (s2), (n))
85 #define bcopy(s, d, n) memcpy ((d), (s), (n))
88 #define bzero(s, n) memset ((s), 0, (n))
95 /* Define the syntax stuff for \<, \>, etc. */
97 /* This must be nonzero for the wordchar and notwordchar pattern
98 commands in re_match_2. */
103 #ifdef SWITCH_ENUM_BUG
104 #define SWITCH_ENUM_CAST(x) ((int)(x))
106 #define SWITCH_ENUM_CAST(x) (x)
111 extern char *re_syntax_table
;
113 #else /* not SYNTAX_TABLE */
115 /* How many characters in the character set. */
116 #define CHAR_SET_SIZE 256
118 static char re_syntax_table
[CHAR_SET_SIZE
];
129 bzero (re_syntax_table
, sizeof re_syntax_table
);
131 for (c
= 'a'; c
<= 'z'; c
++)
132 re_syntax_table
[c
] = Sword
;
134 for (c
= 'A'; c
<= 'Z'; c
++)
135 re_syntax_table
[c
] = Sword
;
137 for (c
= '0'; c
<= '9'; c
++)
138 re_syntax_table
[c
] = Sword
;
140 re_syntax_table
['_'] = Sword
;
145 #endif /* not SYNTAX_TABLE */
147 #define SYNTAX(c) re_syntax_table[c]
149 #endif /* not emacs */
151 /* Get the interface, including the syntax bits. */
154 /* isalpha etc. are used for the character classes. */
157 /* Jim Meyering writes:
159 "... Some ctype macros are valid only for character codes that
160 isascii says are ASCII (SGI's IRIX-4.0.5 is one such system --when
161 using /bin/cc or gcc but without giving an ansi option). So, all
162 ctype uses should be through macros like ISPRINT... If
163 STDC_HEADERS is defined, then autoconf has verified that the ctype
164 macros don't need to be guarded with references to isascii. ...
165 Defining isascii to 1 should let any compiler worth its salt
166 eliminate the && through constant folding." */
168 #if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII))
171 #define ISASCII(c) isascii(c)
175 #define ISBLANK(c) (ISASCII (c) && isblank (c))
177 #define ISBLANK(c) ((c) == ' ' || (c) == '\t')
180 #define ISGRAPH(c) (ISASCII (c) && isgraph (c))
182 #define ISGRAPH(c) (ISASCII (c) && isprint (c) && !isspace (c))
185 #define ISPRINT(c) (ISASCII (c) && isprint (c))
186 #define ISDIGIT(c) (ISASCII (c) && isdigit (c))
187 #define ISALNUM(c) (ISASCII (c) && isalnum (c))
188 #define ISALPHA(c) (ISASCII (c) && isalpha (c))
189 #define ISCNTRL(c) (ISASCII (c) && iscntrl (c))
190 #define ISLOWER(c) (ISASCII (c) && islower (c))
191 #define ISPUNCT(c) (ISASCII (c) && ispunct (c))
192 #define ISSPACE(c) (ISASCII (c) && isspace (c))
193 #define ISUPPER(c) (ISASCII (c) && isupper (c))
194 #define ISXDIGIT(c) (ISASCII (c) && isxdigit (c))
197 #define NULL (void *)0
200 /* We remove any previous definition of `SIGN_EXTEND_CHAR',
201 since ours (we hope) works properly with all combinations of
202 machines, compilers, `char' and `unsigned char' argument types.
203 (Per Bothner suggested the basic approach.) */
204 #undef SIGN_EXTEND_CHAR
206 #define SIGN_EXTEND_CHAR(c) ((signed char) (c))
207 #else /* not __STDC__ */
208 /* As in Harbison and Steele. */
209 #define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128)
212 /* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we
213 use `alloca' instead of `malloc'. This is because using malloc in
214 re_search* or re_match* could cause memory leaks when C-g is used in
215 Emacs; also, malloc is slower and causes storage fragmentation. On
216 the other hand, malloc is more portable, and easier to debug.
218 Because we sometimes use alloca, some routines have to be macros,
219 not functions -- `alloca'-allocated space disappears at the end of the
220 function it is called in. */
224 #define REGEX_ALLOCATE malloc
225 #define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
226 #define REGEX_FREE free
228 #else /* not REGEX_MALLOC */
230 /* Emacs already defines alloca, sometimes. */
233 /* Make alloca work the best possible way. */
235 #define alloca __builtin_alloca
236 #else /* not __GNUC__ */
239 #else /* not __GNUC__ or HAVE_ALLOCA_H */
240 #ifndef _AIX /* Already did AIX, up at the top. */
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. */
263 #if defined (REL_ALLOC) && defined (REGEX_MALLOC)
265 #define REGEX_ALLOCATE_STACK(size) \
266 r_alloc (&failure_stack_ptr, (size))
267 #define REGEX_REALLOCATE_STACK(source, osize, nsize) \
268 r_re_alloc (&failure_stack_ptr, (nsize))
269 #define REGEX_FREE_STACK(ptr) \
270 r_alloc_free (&failure_stack_ptr)
272 #else /* not using relocating allocator */
276 #define REGEX_ALLOCATE_STACK malloc
277 #define REGEX_REALLOCATE_STACK(source, osize, nsize) realloc (source, nsize)
278 #define REGEX_FREE_STACK free
280 #else /* not REGEX_MALLOC */
282 #define REGEX_ALLOCATE_STACK alloca
284 #define REGEX_REALLOCATE_STACK(source, osize, nsize) \
285 REGEX_REALLOCATE (source, osize, nsize)
286 /* No need to explicitly free anything. */
287 #define REGEX_FREE_STACK(arg)
289 #endif /* not REGEX_MALLOC */
290 #endif /* not using relocating allocator */
293 /* True if `size1' is non-NULL and PTR is pointing anywhere inside
294 `string1' or just past its end. This works if PTR is NULL, which is
296 #define FIRST_STRING_P(ptr) \
297 (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
299 /* (Re)Allocate N items of type T using malloc, or fail. */
300 #define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
301 #define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
302 #define RETALLOC_IF(addr, n, t) \
303 if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
304 #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
306 #define BYTEWIDTH 8 /* In bits. */
308 #define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
312 #define MAX(a, b) ((a) > (b) ? (a) : (b))
313 #define MIN(a, b) ((a) < (b) ? (a) : (b))
315 typedef char boolean
;
319 static int re_match_2_internal ();
321 /* These are the command codes that appear in compiled regular
322 expressions. Some opcodes are followed by argument bytes. A
323 command code can specify any interpretation whatsoever for its
324 arguments. Zero bytes may appear in the compiled regular expression. */
330 /* Succeed right away--no more backtracking. */
333 /* Followed by one byte giving n, then by n literal bytes. */
336 /* Matches any (more or less) character. */
339 /* Matches any one char belonging to specified set. First
340 following byte is number of bitmap bytes. Then come bytes
341 for a bitmap saying which chars are in. Bits in each byte
342 are ordered low-bit-first. A character is in the set if its
343 bit is 1. A character too large to have a bit in the map is
344 automatically not in the set. */
347 /* Same parameters as charset, but match any character that is
348 not one of those specified. */
351 /* Start remembering the text that is matched, for storing in a
352 register. Followed by one byte with the register number, in
353 the range 0 to one less than the pattern buffer's re_nsub
354 field. Then followed by one byte with the number of groups
355 inner to this one. (This last has to be part of the
356 start_memory only because we need it in the on_failure_jump
360 /* Stop remembering the text that is matched and store it in a
361 memory register. Followed by one byte with the register
362 number, in the range 0 to one less than `re_nsub' in the
363 pattern buffer, and one byte with the number of inner groups,
364 just like `start_memory'. (We need the number of inner
365 groups here because we don't have any easy way of finding the
366 corresponding start_memory when we're at a stop_memory.) */
369 /* Match a duplicate of something remembered. Followed by one
370 byte containing the register number. */
373 /* Fail unless at beginning of line. */
376 /* Fail unless at end of line. */
379 /* Succeeds if at beginning of buffer (if emacs) or at beginning
380 of string to be matched (if not). */
383 /* Analogously, for end of buffer/string. */
386 /* Followed by two byte relative address to which to jump. */
389 /* Same as jump, but marks the end of an alternative. */
392 /* Followed by two-byte relative address of place to resume at
393 in case of failure. */
396 /* Like on_failure_jump, but pushes a placeholder instead of the
397 current string position when executed. */
398 on_failure_keep_string_jump
,
400 /* Throw away latest failure point and then jump to following
401 two-byte relative address. */
404 /* Change to pop_failure_jump if know won't have to backtrack to
405 match; otherwise change to jump. This is used to jump
406 back to the beginning of a repeat. If what follows this jump
407 clearly won't match what the repeat does, such that we can be
408 sure that there is no use backtracking out of repetitions
409 already matched, then we change it to a pop_failure_jump.
410 Followed by two-byte address. */
413 /* Jump to following two-byte address, and push a dummy failure
414 point. This failure point will be thrown away if an attempt
415 is made to use it for a failure. A `+' construct makes this
416 before the first repeat. Also used as an intermediary kind
417 of jump when compiling an alternative. */
420 /* Push a dummy failure point and continue. Used at the end of
424 /* Followed by two-byte relative address and two-byte number n.
425 After matching N times, jump to the address upon failure. */
428 /* Followed by two-byte relative address, and two-byte number n.
429 Jump to the address N times, then fail. */
432 /* Set the following two-byte relative address to the
433 subsequent two-byte number. The address *includes* the two
437 wordchar
, /* Matches any word-constituent character. */
438 notwordchar
, /* Matches any char that is not a word-constituent. */
440 wordbeg
, /* Succeeds if at word beginning. */
441 wordend
, /* Succeeds if at word end. */
443 wordbound
, /* Succeeds if at a word boundary. */
444 notwordbound
/* Succeeds if not at a word boundary. */
447 ,before_dot
, /* Succeeds if before point. */
448 at_dot
, /* Succeeds if at point. */
449 after_dot
, /* Succeeds if after point. */
451 /* Matches any character whose syntax is specified. Followed by
452 a byte which contains a syntax code, e.g., Sword. */
455 /* Matches any character whose syntax is not that specified. */
460 /* Common operations on the compiled pattern. */
462 /* Store NUMBER in two contiguous bytes starting at DESTINATION. */
464 #define STORE_NUMBER(destination, number) \
466 (destination)[0] = (number) & 0377; \
467 (destination)[1] = (number) >> 8; \
470 /* Same as STORE_NUMBER, except increment DESTINATION to
471 the byte after where the number is stored. Therefore, DESTINATION
472 must be an lvalue. */
474 #define STORE_NUMBER_AND_INCR(destination, number) \
476 STORE_NUMBER (destination, number); \
477 (destination) += 2; \
480 /* Put into DESTINATION a number stored in two contiguous bytes starting
483 #define EXTRACT_NUMBER(destination, source) \
485 (destination) = *(source) & 0377; \
486 (destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8; \
491 extract_number (dest
, source
)
493 unsigned char *source
;
495 int temp
= SIGN_EXTEND_CHAR (*(source
+ 1));
496 *dest
= *source
& 0377;
500 #ifndef EXTRACT_MACROS /* To debug the macros. */
501 #undef EXTRACT_NUMBER
502 #define EXTRACT_NUMBER(dest, src) extract_number (&dest, src)
503 #endif /* not EXTRACT_MACROS */
507 /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
508 SOURCE must be an lvalue. */
510 #define EXTRACT_NUMBER_AND_INCR(destination, source) \
512 EXTRACT_NUMBER (destination, source); \
518 extract_number_and_incr (destination
, source
)
520 unsigned char **source
;
522 extract_number (destination
, *source
);
526 #ifndef EXTRACT_MACROS
527 #undef EXTRACT_NUMBER_AND_INCR
528 #define EXTRACT_NUMBER_AND_INCR(dest, src) \
529 extract_number_and_incr (&dest, &src)
530 #endif /* not EXTRACT_MACROS */
534 /* If DEBUG is defined, Regex prints many voluminous messages about what
535 it is doing (if the variable `debug' is nonzero). If linked with the
536 main program in `iregex.c', you can enter patterns and strings
537 interactively. And if linked with the main program in `main.c' and
538 the other test files, you can run the already-written tests. */
542 /* We use standard I/O for debugging. */
545 /* It is useful to test things that ``must'' be true when debugging. */
548 static int debug
= 0;
550 #define DEBUG_STATEMENT(e) e
551 #define DEBUG_PRINT1(x) if (debug) printf (x)
552 #define DEBUG_PRINT2(x1, x2) if (debug) printf (x1, x2)
553 #define DEBUG_PRINT3(x1, x2, x3) if (debug) printf (x1, x2, x3)
554 #define DEBUG_PRINT4(x1, x2, x3, x4) if (debug) printf (x1, x2, x3, x4)
555 #define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) \
556 if (debug) print_partial_compiled_pattern (s, e)
557 #define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) \
558 if (debug) print_double_string (w, s1, sz1, s2, sz2)
561 /* Print the fastmap in human-readable form. */
564 print_fastmap (fastmap
)
567 unsigned was_a_range
= 0;
570 while (i
< (1 << BYTEWIDTH
))
576 while (i
< (1 << BYTEWIDTH
) && fastmap
[i
])
592 /* Print a compiled pattern string in human-readable form, starting at
593 the START pointer into it and ending just before the pointer END. */
596 print_partial_compiled_pattern (start
, end
)
597 unsigned char *start
;
601 unsigned char *p
= start
;
602 unsigned char *pend
= end
;
610 /* Loop over pattern commands. */
613 printf ("%d:\t", p
- start
);
615 switch ((re_opcode_t
) *p
++)
623 printf ("/exactn/%d", mcnt
);
634 printf ("/start_memory/%d/%d", mcnt
, *p
++);
639 printf ("/stop_memory/%d/%d", mcnt
, *p
++);
643 printf ("/duplicate/%d", *p
++);
653 register int c
, last
= -100;
654 register int in_range
= 0;
656 printf ("/charset [%s",
657 (re_opcode_t
) *(p
- 1) == charset_not
? "^" : "");
659 assert (p
+ *p
< pend
);
661 for (c
= 0; c
< 256; c
++)
663 && (p
[1 + (c
/8)] & (1 << (c
% 8))))
665 /* Are we starting a range? */
666 if (last
+ 1 == c
&& ! in_range
)
671 /* Have we broken a range? */
672 else if (last
+ 1 != c
&& in_range
)
701 case on_failure_jump
:
702 extract_number_and_incr (&mcnt
, &p
);
703 printf ("/on_failure_jump to %d", p
+ mcnt
- start
);
706 case on_failure_keep_string_jump
:
707 extract_number_and_incr (&mcnt
, &p
);
708 printf ("/on_failure_keep_string_jump to %d", p
+ mcnt
- start
);
711 case dummy_failure_jump
:
712 extract_number_and_incr (&mcnt
, &p
);
713 printf ("/dummy_failure_jump to %d", p
+ mcnt
- start
);
716 case push_dummy_failure
:
717 printf ("/push_dummy_failure");
721 extract_number_and_incr (&mcnt
, &p
);
722 printf ("/maybe_pop_jump to %d", p
+ mcnt
- start
);
725 case pop_failure_jump
:
726 extract_number_and_incr (&mcnt
, &p
);
727 printf ("/pop_failure_jump to %d", p
+ mcnt
- start
);
731 extract_number_and_incr (&mcnt
, &p
);
732 printf ("/jump_past_alt to %d", p
+ mcnt
- start
);
736 extract_number_and_incr (&mcnt
, &p
);
737 printf ("/jump to %d", p
+ mcnt
- start
);
741 extract_number_and_incr (&mcnt
, &p
);
742 extract_number_and_incr (&mcnt2
, &p
);
743 printf ("/succeed_n to %d, %d times", p
+ mcnt
- start
, mcnt2
);
747 extract_number_and_incr (&mcnt
, &p
);
748 extract_number_and_incr (&mcnt2
, &p
);
749 printf ("/jump_n to %d, %d times", p
+ mcnt
- start
, mcnt2
);
753 extract_number_and_incr (&mcnt
, &p
);
754 extract_number_and_incr (&mcnt2
, &p
);
755 printf ("/set_number_at location %d to %d", p
+ mcnt
- start
, mcnt2
);
759 printf ("/wordbound");
763 printf ("/notwordbound");
775 printf ("/before_dot");
783 printf ("/after_dot");
787 printf ("/syntaxspec");
789 printf ("/%d", mcnt
);
793 printf ("/notsyntaxspec");
795 printf ("/%d", mcnt
);
800 printf ("/wordchar");
804 printf ("/notwordchar");
816 printf ("?%d", *(p
-1));
822 printf ("%d:\tend of pattern.\n", p
- start
);
827 print_compiled_pattern (bufp
)
828 struct re_pattern_buffer
*bufp
;
830 unsigned char *buffer
= bufp
->buffer
;
832 print_partial_compiled_pattern (buffer
, buffer
+ bufp
->used
);
833 printf ("%d bytes used/%d bytes allocated.\n", bufp
->used
, bufp
->allocated
);
835 if (bufp
->fastmap_accurate
&& bufp
->fastmap
)
837 printf ("fastmap: ");
838 print_fastmap (bufp
->fastmap
);
841 printf ("re_nsub: %d\t", bufp
->re_nsub
);
842 printf ("regs_alloc: %d\t", bufp
->regs_allocated
);
843 printf ("can_be_null: %d\t", bufp
->can_be_null
);
844 printf ("newline_anchor: %d\n", bufp
->newline_anchor
);
845 printf ("no_sub: %d\t", bufp
->no_sub
);
846 printf ("not_bol: %d\t", bufp
->not_bol
);
847 printf ("not_eol: %d\t", bufp
->not_eol
);
848 printf ("syntax: %d\n", bufp
->syntax
);
849 /* Perhaps we should print the translate table? */
854 print_double_string (where
, string1
, size1
, string2
, size2
)
867 if (FIRST_STRING_P (where
))
869 for (this_char
= where
- string1
; this_char
< size1
; this_char
++)
870 putchar (string1
[this_char
]);
875 for (this_char
= where
- string2
; this_char
< size2
; this_char
++)
876 putchar (string2
[this_char
]);
880 #else /* not DEBUG */
885 #define DEBUG_STATEMENT(e)
886 #define DEBUG_PRINT1(x)
887 #define DEBUG_PRINT2(x1, x2)
888 #define DEBUG_PRINT3(x1, x2, x3)
889 #define DEBUG_PRINT4(x1, x2, x3, x4)
890 #define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
891 #define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
893 #endif /* not DEBUG */
895 /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
896 also be assigned to arbitrarily: each pattern buffer stores its own
897 syntax, so it can be changed between regex compilations. */
898 /* This has no initializer because initialized variables in Emacs
899 become read-only after dumping. */
900 reg_syntax_t re_syntax_options
;
903 /* Specify the precise syntax of regexps for compilation. This provides
904 for compatibility for various utilities which historically have
905 different, incompatible syntaxes.
907 The argument SYNTAX is a bit mask comprised of the various bits
908 defined in regex.h. We return the old syntax. */
911 re_set_syntax (syntax
)
914 reg_syntax_t ret
= re_syntax_options
;
916 re_syntax_options
= syntax
;
920 /* This table gives an error message for each of the error codes listed
921 in regex.h. Obviously the order here has to be same as there.
922 POSIX doesn't require that we do anything for REG_NOERROR,
923 but why not be nice? */
925 static const char *re_error_msgid
[] =
926 { "Success", /* REG_NOERROR */
927 "No match", /* REG_NOMATCH */
928 "Invalid regular expression", /* REG_BADPAT */
929 "Invalid collation character", /* REG_ECOLLATE */
930 "Invalid character class name", /* REG_ECTYPE */
931 "Trailing backslash", /* REG_EESCAPE */
932 "Invalid back reference", /* REG_ESUBREG */
933 "Unmatched [ or [^", /* REG_EBRACK */
934 "Unmatched ( or \\(", /* REG_EPAREN */
935 "Unmatched \\{", /* REG_EBRACE */
936 "Invalid content of \\{\\}", /* REG_BADBR */
937 "Invalid range end", /* REG_ERANGE */
938 "Memory exhausted", /* REG_ESPACE */
939 "Invalid preceding regular expression", /* REG_BADRPT */
940 "Premature end of regular expression", /* REG_EEND */
941 "Regular expression too big", /* REG_ESIZE */
942 "Unmatched ) or \\)", /* REG_ERPAREN */
945 /* Avoiding alloca during matching, to placate r_alloc. */
947 /* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
948 searching and matching functions should not call alloca. On some
949 systems, alloca is implemented in terms of malloc, and if we're
950 using the relocating allocator routines, then malloc could cause a
951 relocation, which might (if the strings being searched are in the
952 ralloc heap) shift the data out from underneath the regexp
955 Here's another reason to avoid allocation: Emacs
956 processes input from X in a signal handler; processing X input may
957 call malloc; if input arrives while a matching routine is calling
958 malloc, then we're scrod. But Emacs can't just block input while
959 calling matching routines; then we don't notice interrupts when
960 they come in. So, Emacs blocks input around all regexp calls
961 except the matching calls, which it leaves unprotected, in the
962 faith that they will not malloc. */
964 /* Normally, this is fine. */
965 #define MATCH_MAY_ALLOCATE
967 /* When using GNU C, we are not REALLY using the C alloca, no matter
968 what config.h may say. So don't take precautions for it. */
973 /* The match routines may not allocate if (1) they would do it with malloc
974 and (2) it's not safe for them to use malloc.
975 Note that if REL_ALLOC is defined, matching would not use malloc for the
976 failure stack, but we would still use it for the register vectors;
977 so REL_ALLOC should not affect this. */
978 #if (defined (C_ALLOCA) || defined (REGEX_MALLOC)) && defined (emacs)
979 #undef MATCH_MAY_ALLOCATE
983 /* Failure stack declarations and macros; both re_compile_fastmap and
984 re_match_2 use a failure stack. These have to be macros because of
985 REGEX_ALLOCATE_STACK. */
988 /* Number of failure points for which to initially allocate space
989 when matching. If this number is exceeded, we allocate more
990 space, so it is not a hard limit. */
991 #ifndef INIT_FAILURE_ALLOC
992 #define INIT_FAILURE_ALLOC 5
995 /* Roughly the maximum number of failure points on the stack. Would be
996 exactly that if always used MAX_FAILURE_SPACE each time we failed.
997 This is a variable only so users of regex can assign to it; we never
998 change it ourselves. */
999 #if defined (MATCH_MAY_ALLOCATE)
1000 int re_max_failures
= 200000;
1002 int re_max_failures
= 2000;
1005 union fail_stack_elt
1007 unsigned char *pointer
;
1011 typedef union fail_stack_elt fail_stack_elt_t
;
1015 fail_stack_elt_t
*stack
;
1017 unsigned avail
; /* Offset of next open position. */
1020 #define FAIL_STACK_EMPTY() (fail_stack.avail == 0)
1021 #define FAIL_STACK_PTR_EMPTY() (fail_stack_ptr->avail == 0)
1022 #define FAIL_STACK_FULL() (fail_stack.avail == fail_stack.size)
1025 /* Define macros to initialize and free the failure stack.
1026 Do `return -2' if the alloc fails. */
1028 #ifdef MATCH_MAY_ALLOCATE
1029 #define INIT_FAIL_STACK() \
1031 fail_stack.stack = (fail_stack_elt_t *) \
1032 REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * sizeof (fail_stack_elt_t)); \
1034 if (fail_stack.stack == NULL) \
1037 fail_stack.size = INIT_FAILURE_ALLOC; \
1038 fail_stack.avail = 0; \
1041 #define RESET_FAIL_STACK() REGEX_FREE_STACK (fail_stack.stack)
1043 #define INIT_FAIL_STACK() \
1045 fail_stack.avail = 0; \
1048 #define RESET_FAIL_STACK()
1052 /* Double the size of FAIL_STACK, up to approximately `re_max_failures' items.
1054 Return 1 if succeeds, and 0 if either ran out of memory
1055 allocating space for it or it was already too large.
1057 REGEX_REALLOCATE_STACK requires `destination' be declared. */
1059 #define DOUBLE_FAIL_STACK(fail_stack) \
1060 ((fail_stack).size > re_max_failures * MAX_FAILURE_ITEMS \
1062 : ((fail_stack).stack = (fail_stack_elt_t *) \
1063 REGEX_REALLOCATE_STACK ((fail_stack).stack, \
1064 (fail_stack).size * sizeof (fail_stack_elt_t), \
1065 ((fail_stack).size << 1) * sizeof (fail_stack_elt_t)), \
1067 (fail_stack).stack == NULL \
1069 : ((fail_stack).size <<= 1, \
1073 /* Push pointer POINTER on FAIL_STACK.
1074 Return 1 if was able to do so and 0 if ran out of memory allocating
1076 #define PUSH_PATTERN_OP(POINTER, FAIL_STACK) \
1077 ((FAIL_STACK_FULL () \
1078 && !DOUBLE_FAIL_STACK (FAIL_STACK)) \
1080 : ((FAIL_STACK).stack[(FAIL_STACK).avail++].pointer = POINTER, \
1083 /* Push a pointer value onto the failure stack.
1084 Assumes the variable `fail_stack'. Probably should only
1085 be called from within `PUSH_FAILURE_POINT'. */
1086 #define PUSH_FAILURE_POINTER(item) \
1087 fail_stack.stack[fail_stack.avail++].pointer = (unsigned char *) (item)
1089 /* This pushes an integer-valued item onto the failure stack.
1090 Assumes the variable `fail_stack'. Probably should only
1091 be called from within `PUSH_FAILURE_POINT'. */
1092 #define PUSH_FAILURE_INT(item) \
1093 fail_stack.stack[fail_stack.avail++].integer = (item)
1095 /* Push a fail_stack_elt_t value onto the failure stack.
1096 Assumes the variable `fail_stack'. Probably should only
1097 be called from within `PUSH_FAILURE_POINT'. */
1098 #define PUSH_FAILURE_ELT(item) \
1099 fail_stack.stack[fail_stack.avail++] = (item)
1101 /* These three POP... operations complement the three PUSH... operations.
1102 All assume that `fail_stack' is nonempty. */
1103 #define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
1104 #define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
1105 #define POP_FAILURE_ELT() fail_stack.stack[--fail_stack.avail]
1107 /* Used to omit pushing failure point id's when we're not debugging. */
1109 #define DEBUG_PUSH PUSH_FAILURE_INT
1110 #define DEBUG_POP(item_addr) *(item_addr) = POP_FAILURE_INT ()
1112 #define DEBUG_PUSH(item)
1113 #define DEBUG_POP(item_addr)
1117 /* Push the information about the state we will need
1118 if we ever fail back to it.
1120 Requires variables fail_stack, regstart, regend, reg_info, and
1121 num_regs be declared. DOUBLE_FAIL_STACK requires `destination' be
1124 Does `return FAILURE_CODE' if runs out of memory. */
1126 #define PUSH_FAILURE_POINT(pattern_place, string_place, failure_code) \
1128 char *destination; \
1129 /* Must be int, so when we don't save any registers, the arithmetic \
1130 of 0 + -1 isn't done as unsigned. */ \
1133 DEBUG_STATEMENT (failure_id++); \
1134 DEBUG_STATEMENT (nfailure_points_pushed++); \
1135 DEBUG_PRINT2 ("\nPUSH_FAILURE_POINT #%u:\n", failure_id); \
1136 DEBUG_PRINT2 (" Before push, next avail: %d\n", (fail_stack).avail);\
1137 DEBUG_PRINT2 (" size: %d\n", (fail_stack).size);\
1139 DEBUG_PRINT2 (" slots needed: %d\n", NUM_FAILURE_ITEMS); \
1140 DEBUG_PRINT2 (" available: %d\n", REMAINING_AVAIL_SLOTS); \
1142 /* Ensure we have enough space allocated for what we will push. */ \
1143 while (REMAINING_AVAIL_SLOTS < NUM_FAILURE_ITEMS) \
1145 if (!DOUBLE_FAIL_STACK (fail_stack)) \
1146 return failure_code; \
1148 DEBUG_PRINT2 ("\n Doubled stack; size now: %d\n", \
1149 (fail_stack).size); \
1150 DEBUG_PRINT2 (" slots available: %d\n", REMAINING_AVAIL_SLOTS);\
1153 /* Push the info, starting with the registers. */ \
1154 DEBUG_PRINT1 ("\n"); \
1156 for (this_reg = lowest_active_reg; this_reg <= highest_active_reg; \
1159 DEBUG_PRINT2 (" Pushing reg: %d\n", this_reg); \
1160 DEBUG_STATEMENT (num_regs_pushed++); \
1162 DEBUG_PRINT2 (" start: 0x%x\n", regstart[this_reg]); \
1163 PUSH_FAILURE_POINTER (regstart[this_reg]); \
1165 DEBUG_PRINT2 (" end: 0x%x\n", regend[this_reg]); \
1166 PUSH_FAILURE_POINTER (regend[this_reg]); \
1168 DEBUG_PRINT2 (" info: 0x%x\n ", reg_info[this_reg]); \
1169 DEBUG_PRINT2 (" match_null=%d", \
1170 REG_MATCH_NULL_STRING_P (reg_info[this_reg])); \
1171 DEBUG_PRINT2 (" active=%d", IS_ACTIVE (reg_info[this_reg])); \
1172 DEBUG_PRINT2 (" matched_something=%d", \
1173 MATCHED_SOMETHING (reg_info[this_reg])); \
1174 DEBUG_PRINT2 (" ever_matched=%d", \
1175 EVER_MATCHED_SOMETHING (reg_info[this_reg])); \
1176 DEBUG_PRINT1 ("\n"); \
1177 PUSH_FAILURE_ELT (reg_info[this_reg].word); \
1180 DEBUG_PRINT2 (" Pushing low active reg: %d\n", lowest_active_reg);\
1181 PUSH_FAILURE_INT (lowest_active_reg); \
1183 DEBUG_PRINT2 (" Pushing high active reg: %d\n", highest_active_reg);\
1184 PUSH_FAILURE_INT (highest_active_reg); \
1186 DEBUG_PRINT2 (" Pushing pattern 0x%x: ", pattern_place); \
1187 DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern_place, pend); \
1188 PUSH_FAILURE_POINTER (pattern_place); \
1190 DEBUG_PRINT2 (" Pushing string 0x%x: `", string_place); \
1191 DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2, \
1193 DEBUG_PRINT1 ("'\n"); \
1194 PUSH_FAILURE_POINTER (string_place); \
1196 DEBUG_PRINT2 (" Pushing failure id: %u\n", failure_id); \
1197 DEBUG_PUSH (failure_id); \
1200 /* This is the number of items that are pushed and popped on the stack
1201 for each register. */
1202 #define NUM_REG_ITEMS 3
1204 /* Individual items aside from the registers. */
1206 #define NUM_NONREG_ITEMS 5 /* Includes failure point id. */
1208 #define NUM_NONREG_ITEMS 4
1211 /* We push at most this many items on the stack. */
1212 #define MAX_FAILURE_ITEMS ((num_regs - 1) * NUM_REG_ITEMS + NUM_NONREG_ITEMS)
1214 /* We actually push this many items. */
1215 #define NUM_FAILURE_ITEMS \
1216 ((highest_active_reg - lowest_active_reg + 1) * NUM_REG_ITEMS \
1219 /* How many items can still be added to the stack without overflowing it. */
1220 #define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
1223 /* Pops what PUSH_FAIL_STACK pushes.
1225 We restore into the parameters, all of which should be lvalues:
1226 STR -- the saved data position.
1227 PAT -- the saved pattern position.
1228 LOW_REG, HIGH_REG -- the highest and lowest active registers.
1229 REGSTART, REGEND -- arrays of string positions.
1230 REG_INFO -- array of information about each subexpression.
1232 Also assumes the variables `fail_stack' and (if debugging), `bufp',
1233 `pend', `string1', `size1', `string2', and `size2'. */
1235 #define POP_FAILURE_POINT(str, pat, low_reg, high_reg, regstart, regend, reg_info)\
1237 DEBUG_STATEMENT (fail_stack_elt_t failure_id;) \
1239 const unsigned char *string_temp; \
1241 assert (!FAIL_STACK_EMPTY ()); \
1243 /* Remove failure points and point to how many regs pushed. */ \
1244 DEBUG_PRINT1 ("POP_FAILURE_POINT:\n"); \
1245 DEBUG_PRINT2 (" Before pop, next avail: %d\n", fail_stack.avail); \
1246 DEBUG_PRINT2 (" size: %d\n", fail_stack.size); \
1248 assert (fail_stack.avail >= NUM_NONREG_ITEMS); \
1250 DEBUG_POP (&failure_id); \
1251 DEBUG_PRINT2 (" Popping failure id: %u\n", failure_id); \
1253 /* If the saved string location is NULL, it came from an \
1254 on_failure_keep_string_jump opcode, and we want to throw away the \
1255 saved NULL, thus retaining our current position in the string. */ \
1256 string_temp = POP_FAILURE_POINTER (); \
1257 if (string_temp != NULL) \
1258 str = (const char *) string_temp; \
1260 DEBUG_PRINT2 (" Popping string 0x%x: `", str); \
1261 DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2); \
1262 DEBUG_PRINT1 ("'\n"); \
1264 pat = (unsigned char *) POP_FAILURE_POINTER (); \
1265 DEBUG_PRINT2 (" Popping pattern 0x%x: ", pat); \
1266 DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend); \
1268 /* Restore register info. */ \
1269 high_reg = (unsigned) POP_FAILURE_INT (); \
1270 DEBUG_PRINT2 (" Popping high active reg: %d\n", high_reg); \
1272 low_reg = (unsigned) POP_FAILURE_INT (); \
1273 DEBUG_PRINT2 (" Popping low active reg: %d\n", low_reg); \
1275 for (this_reg = high_reg; this_reg >= low_reg; this_reg--) \
1277 DEBUG_PRINT2 (" Popping reg: %d\n", this_reg); \
1279 reg_info[this_reg].word = POP_FAILURE_ELT (); \
1280 DEBUG_PRINT2 (" info: 0x%x\n", reg_info[this_reg]); \
1282 regend[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1283 DEBUG_PRINT2 (" end: 0x%x\n", regend[this_reg]); \
1285 regstart[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1286 DEBUG_PRINT2 (" start: 0x%x\n", regstart[this_reg]); \
1289 set_regs_matched_done = 0; \
1290 DEBUG_STATEMENT (nfailure_points_popped++); \
1291 } /* POP_FAILURE_POINT */
1295 /* Structure for per-register (a.k.a. per-group) information.
1296 Other register information, such as the
1297 starting and ending positions (which are addresses), and the list of
1298 inner groups (which is a bits list) are maintained in separate
1301 We are making a (strictly speaking) nonportable assumption here: that
1302 the compiler will pack our bit fields into something that fits into
1303 the type of `word', i.e., is something that fits into one item on the
1308 fail_stack_elt_t word
;
1311 /* This field is one if this group can match the empty string,
1312 zero if not. If not yet determined, `MATCH_NULL_UNSET_VALUE'. */
1313 #define MATCH_NULL_UNSET_VALUE 3
1314 unsigned match_null_string_p
: 2;
1315 unsigned is_active
: 1;
1316 unsigned matched_something
: 1;
1317 unsigned ever_matched_something
: 1;
1319 } register_info_type
;
1321 #define REG_MATCH_NULL_STRING_P(R) ((R).bits.match_null_string_p)
1322 #define IS_ACTIVE(R) ((R).bits.is_active)
1323 #define MATCHED_SOMETHING(R) ((R).bits.matched_something)
1324 #define EVER_MATCHED_SOMETHING(R) ((R).bits.ever_matched_something)
1327 /* Call this when have matched a real character; it sets `matched' flags
1328 for the subexpressions which we are currently inside. Also records
1329 that those subexprs have matched. */
1330 #define SET_REGS_MATCHED() \
1333 if (!set_regs_matched_done) \
1336 set_regs_matched_done = 1; \
1337 for (r = lowest_active_reg; r <= highest_active_reg; r++) \
1339 MATCHED_SOMETHING (reg_info[r]) \
1340 = EVER_MATCHED_SOMETHING (reg_info[r]) \
1347 /* Registers are set to a sentinel when they haven't yet matched. */
1348 static char reg_unset_dummy
;
1349 #define REG_UNSET_VALUE (®_unset_dummy)
1350 #define REG_UNSET(e) ((e) == REG_UNSET_VALUE)
1352 /* Subroutine declarations and macros for regex_compile. */
1354 static void store_op1 (), store_op2 ();
1355 static void insert_op1 (), insert_op2 ();
1356 static boolean
at_begline_loc_p (), at_endline_loc_p ();
1357 static boolean
group_in_compile_stack ();
1358 static reg_errcode_t
compile_range ();
1360 /* Fetch the next character in the uncompiled pattern---translating it
1361 if necessary. Also cast from a signed character in the constant
1362 string passed to us by the user to an unsigned char that we can use
1363 as an array index (in, e.g., `translate'). */
1364 #define PATFETCH(c) \
1365 do {if (p == pend) return REG_EEND; \
1366 c = (unsigned char) *p++; \
1367 if (translate) c = translate[c]; \
1370 /* Fetch the next character in the uncompiled pattern, with no
1372 #define PATFETCH_RAW(c) \
1373 do {if (p == pend) return REG_EEND; \
1374 c = (unsigned char) *p++; \
1377 /* Go backwards one character in the pattern. */
1378 #define PATUNFETCH p--
1381 /* If `translate' is non-null, return translate[D], else just D. We
1382 cast the subscript to translate because some data is declared as
1383 `char *', to avoid warnings when a string constant is passed. But
1384 when we use a character as a subscript we must make it unsigned. */
1385 #define TRANSLATE(d) (translate ? translate[(unsigned char) (d)] : (d))
1388 /* Macros for outputting the compiled pattern into `buffer'. */
1390 /* If the buffer isn't allocated when it comes in, use this. */
1391 #define INIT_BUF_SIZE 32
1393 /* Make sure we have at least N more bytes of space in buffer. */
1394 #define GET_BUFFER_SPACE(n) \
1395 while (b - bufp->buffer + (n) > bufp->allocated) \
1398 /* Make sure we have one more byte of buffer space and then add C to it. */
1399 #define BUF_PUSH(c) \
1401 GET_BUFFER_SPACE (1); \
1402 *b++ = (unsigned char) (c); \
1406 /* Ensure we have two more bytes of buffer space and then append C1 and C2. */
1407 #define BUF_PUSH_2(c1, c2) \
1409 GET_BUFFER_SPACE (2); \
1410 *b++ = (unsigned char) (c1); \
1411 *b++ = (unsigned char) (c2); \
1415 /* As with BUF_PUSH_2, except for three bytes. */
1416 #define BUF_PUSH_3(c1, c2, c3) \
1418 GET_BUFFER_SPACE (3); \
1419 *b++ = (unsigned char) (c1); \
1420 *b++ = (unsigned char) (c2); \
1421 *b++ = (unsigned char) (c3); \
1425 /* Store a jump with opcode OP at LOC to location TO. We store a
1426 relative address offset by the three bytes the jump itself occupies. */
1427 #define STORE_JUMP(op, loc, to) \
1428 store_op1 (op, loc, (to) - (loc) - 3)
1430 /* Likewise, for a two-argument jump. */
1431 #define STORE_JUMP2(op, loc, to, arg) \
1432 store_op2 (op, loc, (to) - (loc) - 3, arg)
1434 /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
1435 #define INSERT_JUMP(op, loc, to) \
1436 insert_op1 (op, loc, (to) - (loc) - 3, b)
1438 /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
1439 #define INSERT_JUMP2(op, loc, to, arg) \
1440 insert_op2 (op, loc, (to) - (loc) - 3, arg, b)
1443 /* This is not an arbitrary limit: the arguments which represent offsets
1444 into the pattern are two bytes long. So if 2^16 bytes turns out to
1445 be too small, many things would have to change. */
1446 #define MAX_BUF_SIZE (1L << 16)
1449 /* Extend the buffer by twice its current size via realloc and
1450 reset the pointers that pointed into the old block to point to the
1451 correct places in the new one. If extending the buffer results in it
1452 being larger than MAX_BUF_SIZE, then flag memory exhausted. */
1453 #define EXTEND_BUFFER() \
1455 unsigned char *old_buffer = bufp->buffer; \
1456 if (bufp->allocated == MAX_BUF_SIZE) \
1458 bufp->allocated <<= 1; \
1459 if (bufp->allocated > MAX_BUF_SIZE) \
1460 bufp->allocated = MAX_BUF_SIZE; \
1461 bufp->buffer = (unsigned char *) realloc (bufp->buffer, bufp->allocated);\
1462 if (bufp->buffer == NULL) \
1463 return REG_ESPACE; \
1464 /* If the buffer moved, move all the pointers into it. */ \
1465 if (old_buffer != bufp->buffer) \
1467 b = (b - old_buffer) + bufp->buffer; \
1468 begalt = (begalt - old_buffer) + bufp->buffer; \
1469 if (fixup_alt_jump) \
1470 fixup_alt_jump = (fixup_alt_jump - old_buffer) + bufp->buffer;\
1472 laststart = (laststart - old_buffer) + bufp->buffer; \
1473 if (pending_exact) \
1474 pending_exact = (pending_exact - old_buffer) + bufp->buffer; \
1479 /* Since we have one byte reserved for the register number argument to
1480 {start,stop}_memory, the maximum number of groups we can report
1481 things about is what fits in that byte. */
1482 #define MAX_REGNUM 255
1484 /* But patterns can have more than `MAX_REGNUM' registers. We just
1485 ignore the excess. */
1486 typedef unsigned regnum_t
;
1489 /* Macros for the compile stack. */
1491 /* Since offsets can go either forwards or backwards, this type needs to
1492 be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
1493 typedef int pattern_offset_t
;
1497 pattern_offset_t begalt_offset
;
1498 pattern_offset_t fixup_alt_jump
;
1499 pattern_offset_t inner_group_offset
;
1500 pattern_offset_t laststart_offset
;
1502 } compile_stack_elt_t
;
1507 compile_stack_elt_t
*stack
;
1509 unsigned avail
; /* Offset of next open position. */
1510 } compile_stack_type
;
1513 #define INIT_COMPILE_STACK_SIZE 32
1515 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
1516 #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
1518 /* The next available element. */
1519 #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
1522 /* Set the bit for character C in a list. */
1523 #define SET_LIST_BIT(c) \
1524 (b[((unsigned char) (c)) / BYTEWIDTH] \
1525 |= 1 << (((unsigned char) c) % BYTEWIDTH))
1528 /* Get the next unsigned number in the uncompiled pattern. */
1529 #define GET_UNSIGNED_NUMBER(num) \
1533 while (ISDIGIT (c)) \
1537 num = num * 10 + c - '0'; \
1545 #define CHAR_CLASS_MAX_LENGTH 6 /* Namely, `xdigit'. */
1547 #define IS_CHAR_CLASS(string) \
1548 (STREQ (string, "alpha") || STREQ (string, "upper") \
1549 || STREQ (string, "lower") || STREQ (string, "digit") \
1550 || STREQ (string, "alnum") || STREQ (string, "xdigit") \
1551 || STREQ (string, "space") || STREQ (string, "print") \
1552 || STREQ (string, "punct") || STREQ (string, "graph") \
1553 || STREQ (string, "cntrl") || STREQ (string, "blank"))
1555 #ifndef MATCH_MAY_ALLOCATE
1557 /* If we cannot allocate large objects within re_match_2_internal,
1558 we make the fail stack and register vectors global.
1559 The fail stack, we grow to the maximum size when a regexp
1561 The register vectors, we adjust in size each time we
1562 compile a regexp, according to the number of registers it needs. */
1564 static fail_stack_type fail_stack
;
1566 /* Size with which the following vectors are currently allocated.
1567 That is so we can make them bigger as needed,
1568 but never make them smaller. */
1569 static int regs_allocated_size
;
1571 static const char ** regstart
, ** regend
;
1572 static const char ** old_regstart
, ** old_regend
;
1573 static const char **best_regstart
, **best_regend
;
1574 static register_info_type
*reg_info
;
1575 static const char **reg_dummy
;
1576 static register_info_type
*reg_info_dummy
;
1578 /* Make the register vectors big enough for NUM_REGS registers,
1579 but don't make them smaller. */
1582 regex_grow_registers (num_regs
)
1585 if (num_regs
> regs_allocated_size
)
1587 RETALLOC_IF (regstart
, num_regs
, const char *);
1588 RETALLOC_IF (regend
, num_regs
, const char *);
1589 RETALLOC_IF (old_regstart
, num_regs
, const char *);
1590 RETALLOC_IF (old_regend
, num_regs
, const char *);
1591 RETALLOC_IF (best_regstart
, num_regs
, const char *);
1592 RETALLOC_IF (best_regend
, num_regs
, const char *);
1593 RETALLOC_IF (reg_info
, num_regs
, register_info_type
);
1594 RETALLOC_IF (reg_dummy
, num_regs
, const char *);
1595 RETALLOC_IF (reg_info_dummy
, num_regs
, register_info_type
);
1597 regs_allocated_size
= num_regs
;
1601 #endif /* not MATCH_MAY_ALLOCATE */
1603 /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
1604 Returns one of error codes defined in `regex.h', or zero for success.
1606 Assumes the `allocated' (and perhaps `buffer') and `translate'
1607 fields are set in BUFP on entry.
1609 If it succeeds, results are put in BUFP (if it returns an error, the
1610 contents of BUFP are undefined):
1611 `buffer' is the compiled pattern;
1612 `syntax' is set to SYNTAX;
1613 `used' is set to the length of the compiled pattern;
1614 `fastmap_accurate' is zero;
1615 `re_nsub' is the number of subexpressions in PATTERN;
1616 `not_bol' and `not_eol' are zero;
1618 The `fastmap' and `newline_anchor' fields are neither
1619 examined nor set. */
1621 /* Return, freeing storage we allocated. */
1622 #define FREE_STACK_RETURN(value) \
1623 return (free (compile_stack.stack), value)
1625 static reg_errcode_t
1626 regex_compile (pattern
, size
, syntax
, bufp
)
1627 const char *pattern
;
1629 reg_syntax_t syntax
;
1630 struct re_pattern_buffer
*bufp
;
1632 /* We fetch characters from PATTERN here. Even though PATTERN is
1633 `char *' (i.e., signed), we declare these variables as unsigned, so
1634 they can be reliably used as array indices. */
1635 register unsigned char c
, c1
;
1637 /* A random temporary spot in PATTERN. */
1640 /* Points to the end of the buffer, where we should append. */
1641 register unsigned char *b
;
1643 /* Keeps track of unclosed groups. */
1644 compile_stack_type compile_stack
;
1646 /* Points to the current (ending) position in the pattern. */
1647 const char *p
= pattern
;
1648 const char *pend
= pattern
+ size
;
1650 /* How to translate the characters in the pattern. */
1651 char *translate
= bufp
->translate
;
1653 /* Address of the count-byte of the most recently inserted `exactn'
1654 command. This makes it possible to tell if a new exact-match
1655 character can be added to that command or if the character requires
1656 a new `exactn' command. */
1657 unsigned char *pending_exact
= 0;
1659 /* Address of start of the most recently finished expression.
1660 This tells, e.g., postfix * where to find the start of its
1661 operand. Reset at the beginning of groups and alternatives. */
1662 unsigned char *laststart
= 0;
1664 /* Address of beginning of regexp, or inside of last group. */
1665 unsigned char *begalt
;
1667 /* Place in the uncompiled pattern (i.e., the {) to
1668 which to go back if the interval is invalid. */
1669 const char *beg_interval
;
1671 /* Address of the place where a forward jump should go to the end of
1672 the containing expression. Each alternative of an `or' -- except the
1673 last -- ends with a forward jump of this sort. */
1674 unsigned char *fixup_alt_jump
= 0;
1676 /* Counts open-groups as they are encountered. Remembered for the
1677 matching close-group on the compile stack, so the same register
1678 number is put in the stop_memory as the start_memory. */
1679 regnum_t regnum
= 0;
1682 DEBUG_PRINT1 ("\nCompiling pattern: ");
1685 unsigned debug_count
;
1687 for (debug_count
= 0; debug_count
< size
; debug_count
++)
1688 putchar (pattern
[debug_count
]);
1693 /* Initialize the compile stack. */
1694 compile_stack
.stack
= TALLOC (INIT_COMPILE_STACK_SIZE
, compile_stack_elt_t
);
1695 if (compile_stack
.stack
== NULL
)
1698 compile_stack
.size
= INIT_COMPILE_STACK_SIZE
;
1699 compile_stack
.avail
= 0;
1701 /* Initialize the pattern buffer. */
1702 bufp
->syntax
= syntax
;
1703 bufp
->fastmap_accurate
= 0;
1704 bufp
->not_bol
= bufp
->not_eol
= 0;
1706 /* Set `used' to zero, so that if we return an error, the pattern
1707 printer (for debugging) will think there's no pattern. We reset it
1711 /* Always count groups, whether or not bufp->no_sub is set. */
1714 #if !defined (emacs) && !defined (SYNTAX_TABLE)
1715 /* Initialize the syntax table. */
1716 init_syntax_once ();
1719 if (bufp
->allocated
== 0)
1722 { /* If zero allocated, but buffer is non-null, try to realloc
1723 enough space. This loses if buffer's address is bogus, but
1724 that is the user's responsibility. */
1725 RETALLOC (bufp
->buffer
, INIT_BUF_SIZE
, unsigned char);
1728 { /* Caller did not allocate a buffer. Do it for them. */
1729 bufp
->buffer
= TALLOC (INIT_BUF_SIZE
, unsigned char);
1731 if (!bufp
->buffer
) FREE_STACK_RETURN (REG_ESPACE
);
1733 bufp
->allocated
= INIT_BUF_SIZE
;
1736 begalt
= b
= bufp
->buffer
;
1738 /* Loop through the uncompiled pattern until we're at the end. */
1747 if ( /* If at start of pattern, it's an operator. */
1749 /* If context independent, it's an operator. */
1750 || syntax
& RE_CONTEXT_INDEP_ANCHORS
1751 /* Otherwise, depends on what's come before. */
1752 || at_begline_loc_p (pattern
, p
, syntax
))
1762 if ( /* If at end of pattern, it's an operator. */
1764 /* If context independent, it's an operator. */
1765 || syntax
& RE_CONTEXT_INDEP_ANCHORS
1766 /* Otherwise, depends on what's next. */
1767 || at_endline_loc_p (p
, pend
, syntax
))
1777 if ((syntax
& RE_BK_PLUS_QM
)
1778 || (syntax
& RE_LIMITED_OPS
))
1782 /* If there is no previous pattern... */
1785 if (syntax
& RE_CONTEXT_INVALID_OPS
)
1786 FREE_STACK_RETURN (REG_BADRPT
);
1787 else if (!(syntax
& RE_CONTEXT_INDEP_OPS
))
1792 /* Are we optimizing this jump? */
1793 boolean keep_string_p
= false;
1795 /* 1 means zero (many) matches is allowed. */
1796 char zero_times_ok
= 0, many_times_ok
= 0;
1798 /* If there is a sequence of repetition chars, collapse it
1799 down to just one (the right one). We can't combine
1800 interval operators with these because of, e.g., `a{2}*',
1801 which should only match an even number of `a's. */
1805 zero_times_ok
|= c
!= '+';
1806 many_times_ok
|= c
!= '?';
1814 || (!(syntax
& RE_BK_PLUS_QM
) && (c
== '+' || c
== '?')))
1817 else if (syntax
& RE_BK_PLUS_QM
&& c
== '\\')
1819 if (p
== pend
) FREE_STACK_RETURN (REG_EESCAPE
);
1822 if (!(c1
== '+' || c1
== '?'))
1837 /* If we get here, we found another repeat character. */
1840 /* Star, etc. applied to an empty pattern is equivalent
1841 to an empty pattern. */
1845 /* Now we know whether or not zero matches is allowed
1846 and also whether or not two or more matches is allowed. */
1848 { /* More than one repetition is allowed, so put in at the
1849 end a backward relative jump from `b' to before the next
1850 jump we're going to put in below (which jumps from
1851 laststart to after this jump).
1853 But if we are at the `*' in the exact sequence `.*\n',
1854 insert an unconditional jump backwards to the .,
1855 instead of the beginning of the loop. This way we only
1856 push a failure point once, instead of every time
1857 through the loop. */
1858 assert (p
- 1 > pattern
);
1860 /* Allocate the space for the jump. */
1861 GET_BUFFER_SPACE (3);
1863 /* We know we are not at the first character of the pattern,
1864 because laststart was nonzero. And we've already
1865 incremented `p', by the way, to be the character after
1866 the `*'. Do we have to do something analogous here
1867 for null bytes, because of RE_DOT_NOT_NULL? */
1868 if (TRANSLATE (*(p
- 2)) == TRANSLATE ('.')
1870 && p
< pend
&& TRANSLATE (*p
) == TRANSLATE ('\n')
1871 && !(syntax
& RE_DOT_NEWLINE
))
1872 { /* We have .*\n. */
1873 STORE_JUMP (jump
, b
, laststart
);
1874 keep_string_p
= true;
1877 /* Anything else. */
1878 STORE_JUMP (maybe_pop_jump
, b
, laststart
- 3);
1880 /* We've added more stuff to the buffer. */
1884 /* On failure, jump from laststart to b + 3, which will be the
1885 end of the buffer after this jump is inserted. */
1886 GET_BUFFER_SPACE (3);
1887 INSERT_JUMP (keep_string_p
? on_failure_keep_string_jump
1895 /* At least one repetition is required, so insert a
1896 `dummy_failure_jump' before the initial
1897 `on_failure_jump' instruction of the loop. This
1898 effects a skip over that instruction the first time
1899 we hit that loop. */
1900 GET_BUFFER_SPACE (3);
1901 INSERT_JUMP (dummy_failure_jump
, laststart
, laststart
+ 6);
1916 boolean had_char_class
= false;
1918 if (p
== pend
) FREE_STACK_RETURN (REG_EBRACK
);
1920 /* Ensure that we have enough space to push a charset: the
1921 opcode, the length count, and the bitset; 34 bytes in all. */
1922 GET_BUFFER_SPACE (34);
1926 /* We test `*p == '^' twice, instead of using an if
1927 statement, so we only need one BUF_PUSH. */
1928 BUF_PUSH (*p
== '^' ? charset_not
: charset
);
1932 /* Remember the first position in the bracket expression. */
1935 /* Push the number of bytes in the bitmap. */
1936 BUF_PUSH ((1 << BYTEWIDTH
) / BYTEWIDTH
);
1938 /* Clear the whole map. */
1939 bzero (b
, (1 << BYTEWIDTH
) / BYTEWIDTH
);
1941 /* charset_not matches newline according to a syntax bit. */
1942 if ((re_opcode_t
) b
[-2] == charset_not
1943 && (syntax
& RE_HAT_LISTS_NOT_NEWLINE
))
1944 SET_LIST_BIT ('\n');
1946 /* Read in characters and ranges, setting map bits. */
1949 if (p
== pend
) FREE_STACK_RETURN (REG_EBRACK
);
1953 /* \ might escape characters inside [...] and [^...]. */
1954 if ((syntax
& RE_BACKSLASH_ESCAPE_IN_LISTS
) && c
== '\\')
1956 if (p
== pend
) FREE_STACK_RETURN (REG_EESCAPE
);
1963 /* Could be the end of the bracket expression. If it's
1964 not (i.e., when the bracket expression is `[]' so
1965 far), the ']' character bit gets set way below. */
1966 if (c
== ']' && p
!= p1
+ 1)
1969 /* Look ahead to see if it's a range when the last thing
1970 was a character class. */
1971 if (had_char_class
&& c
== '-' && *p
!= ']')
1972 FREE_STACK_RETURN (REG_ERANGE
);
1974 /* Look ahead to see if it's a range when the last thing
1975 was a character: if this is a hyphen not at the
1976 beginning or the end of a list, then it's the range
1979 && !(p
- 2 >= pattern
&& p
[-2] == '[')
1980 && !(p
- 3 >= pattern
&& p
[-3] == '[' && p
[-2] == '^')
1984 = compile_range (&p
, pend
, translate
, syntax
, b
);
1985 if (ret
!= REG_NOERROR
) FREE_STACK_RETURN (ret
);
1988 else if (p
[0] == '-' && p
[1] != ']')
1989 { /* This handles ranges made up of characters only. */
1992 /* Move past the `-'. */
1995 ret
= compile_range (&p
, pend
, translate
, syntax
, b
);
1996 if (ret
!= REG_NOERROR
) FREE_STACK_RETURN (ret
);
1999 /* See if we're at the beginning of a possible character
2002 else if (syntax
& RE_CHAR_CLASSES
&& c
== '[' && *p
== ':')
2003 { /* Leave room for the null. */
2004 char str
[CHAR_CLASS_MAX_LENGTH
+ 1];
2009 /* If pattern is `[[:'. */
2010 if (p
== pend
) FREE_STACK_RETURN (REG_EBRACK
);
2015 if (c
== ':' || c
== ']' || p
== pend
2016 || c1
== CHAR_CLASS_MAX_LENGTH
)
2022 /* If isn't a word bracketed by `[:' and:`]':
2023 undo the ending character, the letters, and leave
2024 the leading `:' and `[' (but set bits for them). */
2025 if (c
== ':' && *p
== ']')
2028 boolean is_alnum
= STREQ (str
, "alnum");
2029 boolean is_alpha
= STREQ (str
, "alpha");
2030 boolean is_blank
= STREQ (str
, "blank");
2031 boolean is_cntrl
= STREQ (str
, "cntrl");
2032 boolean is_digit
= STREQ (str
, "digit");
2033 boolean is_graph
= STREQ (str
, "graph");
2034 boolean is_lower
= STREQ (str
, "lower");
2035 boolean is_print
= STREQ (str
, "print");
2036 boolean is_punct
= STREQ (str
, "punct");
2037 boolean is_space
= STREQ (str
, "space");
2038 boolean is_upper
= STREQ (str
, "upper");
2039 boolean is_xdigit
= STREQ (str
, "xdigit");
2041 if (!IS_CHAR_CLASS (str
))
2042 FREE_STACK_RETURN (REG_ECTYPE
);
2044 /* Throw away the ] at the end of the character
2048 if (p
== pend
) FREE_STACK_RETURN (REG_EBRACK
);
2050 for (ch
= 0; ch
< 1 << BYTEWIDTH
; ch
++)
2052 /* This was split into 3 if's to
2053 avoid an arbitrary limit in some compiler. */
2054 if ( (is_alnum
&& ISALNUM (ch
))
2055 || (is_alpha
&& ISALPHA (ch
))
2056 || (is_blank
&& ISBLANK (ch
))
2057 || (is_cntrl
&& ISCNTRL (ch
)))
2059 if ( (is_digit
&& ISDIGIT (ch
))
2060 || (is_graph
&& ISGRAPH (ch
))
2061 || (is_lower
&& ISLOWER (ch
))
2062 || (is_print
&& ISPRINT (ch
)))
2064 if ( (is_punct
&& ISPUNCT (ch
))
2065 || (is_space
&& ISSPACE (ch
))
2066 || (is_upper
&& ISUPPER (ch
))
2067 || (is_xdigit
&& ISXDIGIT (ch
)))
2070 had_char_class
= true;
2079 had_char_class
= false;
2084 had_char_class
= false;
2089 /* Discard any (non)matching list bytes that are all 0 at the
2090 end of the map. Decrease the map-length byte too. */
2091 while ((int) b
[-1] > 0 && b
[b
[-1] - 1] == 0)
2099 if (syntax
& RE_NO_BK_PARENS
)
2106 if (syntax
& RE_NO_BK_PARENS
)
2113 if (syntax
& RE_NEWLINE_ALT
)
2120 if (syntax
& RE_NO_BK_VBAR
)
2127 if (syntax
& RE_INTERVALS
&& syntax
& RE_NO_BK_BRACES
)
2128 goto handle_interval
;
2134 if (p
== pend
) FREE_STACK_RETURN (REG_EESCAPE
);
2136 /* Do not translate the character after the \, so that we can
2137 distinguish, e.g., \B from \b, even if we normally would
2138 translate, e.g., B to b. */
2144 if (syntax
& RE_NO_BK_PARENS
)
2145 goto normal_backslash
;
2151 if (COMPILE_STACK_FULL
)
2153 RETALLOC (compile_stack
.stack
, compile_stack
.size
<< 1,
2154 compile_stack_elt_t
);
2155 if (compile_stack
.stack
== NULL
) return REG_ESPACE
;
2157 compile_stack
.size
<<= 1;
2160 /* These are the values to restore when we hit end of this
2161 group. They are all relative offsets, so that if the
2162 whole pattern moves because of realloc, they will still
2164 COMPILE_STACK_TOP
.begalt_offset
= begalt
- bufp
->buffer
;
2165 COMPILE_STACK_TOP
.fixup_alt_jump
2166 = fixup_alt_jump
? fixup_alt_jump
- bufp
->buffer
+ 1 : 0;
2167 COMPILE_STACK_TOP
.laststart_offset
= b
- bufp
->buffer
;
2168 COMPILE_STACK_TOP
.regnum
= regnum
;
2170 /* We will eventually replace the 0 with the number of
2171 groups inner to this one. But do not push a
2172 start_memory for groups beyond the last one we can
2173 represent in the compiled pattern. */
2174 if (regnum
<= MAX_REGNUM
)
2176 COMPILE_STACK_TOP
.inner_group_offset
= b
- bufp
->buffer
+ 2;
2177 BUF_PUSH_3 (start_memory
, regnum
, 0);
2180 compile_stack
.avail
++;
2185 /* If we've reached MAX_REGNUM groups, then this open
2186 won't actually generate any code, so we'll have to
2187 clear pending_exact explicitly. */
2193 if (syntax
& RE_NO_BK_PARENS
) goto normal_backslash
;
2195 if (COMPILE_STACK_EMPTY
)
2196 if (syntax
& RE_UNMATCHED_RIGHT_PAREN_ORD
)
2197 goto normal_backslash
;
2199 FREE_STACK_RETURN (REG_ERPAREN
);
2203 { /* Push a dummy failure point at the end of the
2204 alternative for a possible future
2205 `pop_failure_jump' to pop. See comments at
2206 `push_dummy_failure' in `re_match_2'. */
2207 BUF_PUSH (push_dummy_failure
);
2209 /* We allocated space for this jump when we assigned
2210 to `fixup_alt_jump', in the `handle_alt' case below. */
2211 STORE_JUMP (jump_past_alt
, fixup_alt_jump
, b
- 1);
2214 /* See similar code for backslashed left paren above. */
2215 if (COMPILE_STACK_EMPTY
)
2216 if (syntax
& RE_UNMATCHED_RIGHT_PAREN_ORD
)
2219 FREE_STACK_RETURN (REG_ERPAREN
);
2221 /* Since we just checked for an empty stack above, this
2222 ``can't happen''. */
2223 assert (compile_stack
.avail
!= 0);
2225 /* We don't just want to restore into `regnum', because
2226 later groups should continue to be numbered higher,
2227 as in `(ab)c(de)' -- the second group is #2. */
2228 regnum_t this_group_regnum
;
2230 compile_stack
.avail
--;
2231 begalt
= bufp
->buffer
+ COMPILE_STACK_TOP
.begalt_offset
;
2233 = COMPILE_STACK_TOP
.fixup_alt_jump
2234 ? bufp
->buffer
+ COMPILE_STACK_TOP
.fixup_alt_jump
- 1
2236 laststart
= bufp
->buffer
+ COMPILE_STACK_TOP
.laststart_offset
;
2237 this_group_regnum
= COMPILE_STACK_TOP
.regnum
;
2238 /* If we've reached MAX_REGNUM groups, then this open
2239 won't actually generate any code, so we'll have to
2240 clear pending_exact explicitly. */
2243 /* We're at the end of the group, so now we know how many
2244 groups were inside this one. */
2245 if (this_group_regnum
<= MAX_REGNUM
)
2247 unsigned char *inner_group_loc
2248 = bufp
->buffer
+ COMPILE_STACK_TOP
.inner_group_offset
;
2250 *inner_group_loc
= regnum
- this_group_regnum
;
2251 BUF_PUSH_3 (stop_memory
, this_group_regnum
,
2252 regnum
- this_group_regnum
);
2258 case '|': /* `\|'. */
2259 if (syntax
& RE_LIMITED_OPS
|| syntax
& RE_NO_BK_VBAR
)
2260 goto normal_backslash
;
2262 if (syntax
& RE_LIMITED_OPS
)
2265 /* Insert before the previous alternative a jump which
2266 jumps to this alternative if the former fails. */
2267 GET_BUFFER_SPACE (3);
2268 INSERT_JUMP (on_failure_jump
, begalt
, b
+ 6);
2272 /* The alternative before this one has a jump after it
2273 which gets executed if it gets matched. Adjust that
2274 jump so it will jump to this alternative's analogous
2275 jump (put in below, which in turn will jump to the next
2276 (if any) alternative's such jump, etc.). The last such
2277 jump jumps to the correct final destination. A picture:
2283 If we are at `b', then fixup_alt_jump right now points to a
2284 three-byte space after `a'. We'll put in the jump, set
2285 fixup_alt_jump to right after `b', and leave behind three
2286 bytes which we'll fill in when we get to after `c'. */
2289 STORE_JUMP (jump_past_alt
, fixup_alt_jump
, b
);
2291 /* Mark and leave space for a jump after this alternative,
2292 to be filled in later either by next alternative or
2293 when know we're at the end of a series of alternatives. */
2295 GET_BUFFER_SPACE (3);
2304 /* If \{ is a literal. */
2305 if (!(syntax
& RE_INTERVALS
)
2306 /* If we're at `\{' and it's not the open-interval
2308 || ((syntax
& RE_INTERVALS
) && (syntax
& RE_NO_BK_BRACES
))
2309 || (p
- 2 == pattern
&& p
== pend
))
2310 goto normal_backslash
;
2314 /* If got here, then the syntax allows intervals. */
2316 /* At least (most) this many matches must be made. */
2317 int lower_bound
= -1, upper_bound
= -1;
2319 beg_interval
= p
- 1;
2323 if (syntax
& RE_NO_BK_BRACES
)
2324 goto unfetch_interval
;
2326 FREE_STACK_RETURN (REG_EBRACE
);
2329 GET_UNSIGNED_NUMBER (lower_bound
);
2333 GET_UNSIGNED_NUMBER (upper_bound
);
2334 if (upper_bound
< 0) upper_bound
= RE_DUP_MAX
;
2337 /* Interval such as `{1}' => match exactly once. */
2338 upper_bound
= lower_bound
;
2340 if (lower_bound
< 0 || upper_bound
> RE_DUP_MAX
2341 || lower_bound
> upper_bound
)
2343 if (syntax
& RE_NO_BK_BRACES
)
2344 goto unfetch_interval
;
2346 FREE_STACK_RETURN (REG_BADBR
);
2349 if (!(syntax
& RE_NO_BK_BRACES
))
2351 if (c
!= '\\') FREE_STACK_RETURN (REG_EBRACE
);
2358 if (syntax
& RE_NO_BK_BRACES
)
2359 goto unfetch_interval
;
2361 FREE_STACK_RETURN (REG_BADBR
);
2364 /* We just parsed a valid interval. */
2366 /* If it's invalid to have no preceding re. */
2369 if (syntax
& RE_CONTEXT_INVALID_OPS
)
2370 FREE_STACK_RETURN (REG_BADRPT
);
2371 else if (syntax
& RE_CONTEXT_INDEP_OPS
)
2374 goto unfetch_interval
;
2377 /* If the upper bound is zero, don't want to succeed at
2378 all; jump from `laststart' to `b + 3', which will be
2379 the end of the buffer after we insert the jump. */
2380 if (upper_bound
== 0)
2382 GET_BUFFER_SPACE (3);
2383 INSERT_JUMP (jump
, laststart
, b
+ 3);
2387 /* Otherwise, we have a nontrivial interval. When
2388 we're all done, the pattern will look like:
2389 set_number_at <jump count> <upper bound>
2390 set_number_at <succeed_n count> <lower bound>
2391 succeed_n <after jump addr> <succeed_n count>
2393 jump_n <succeed_n addr> <jump count>
2394 (The upper bound and `jump_n' are omitted if
2395 `upper_bound' is 1, though.) */
2397 { /* If the upper bound is > 1, we need to insert
2398 more at the end of the loop. */
2399 unsigned nbytes
= 10 + (upper_bound
> 1) * 10;
2401 GET_BUFFER_SPACE (nbytes
);
2403 /* Initialize lower bound of the `succeed_n', even
2404 though it will be set during matching by its
2405 attendant `set_number_at' (inserted next),
2406 because `re_compile_fastmap' needs to know.
2407 Jump to the `jump_n' we might insert below. */
2408 INSERT_JUMP2 (succeed_n
, laststart
,
2409 b
+ 5 + (upper_bound
> 1) * 5,
2413 /* Code to initialize the lower bound. Insert
2414 before the `succeed_n'. The `5' is the last two
2415 bytes of this `set_number_at', plus 3 bytes of
2416 the following `succeed_n'. */
2417 insert_op2 (set_number_at
, laststart
, 5, lower_bound
, b
);
2420 if (upper_bound
> 1)
2421 { /* More than one repetition is allowed, so
2422 append a backward jump to the `succeed_n'
2423 that starts this interval.
2425 When we've reached this during matching,
2426 we'll have matched the interval once, so
2427 jump back only `upper_bound - 1' times. */
2428 STORE_JUMP2 (jump_n
, b
, laststart
+ 5,
2432 /* The location we want to set is the second
2433 parameter of the `jump_n'; that is `b-2' as
2434 an absolute address. `laststart' will be
2435 the `set_number_at' we're about to insert;
2436 `laststart+3' the number to set, the source
2437 for the relative address. But we are
2438 inserting into the middle of the pattern --
2439 so everything is getting moved up by 5.
2440 Conclusion: (b - 2) - (laststart + 3) + 5,
2441 i.e., b - laststart.
2443 We insert this at the beginning of the loop
2444 so that if we fail during matching, we'll
2445 reinitialize the bounds. */
2446 insert_op2 (set_number_at
, laststart
, b
- laststart
,
2447 upper_bound
- 1, b
);
2452 beg_interval
= NULL
;
2457 /* If an invalid interval, match the characters as literals. */
2458 assert (beg_interval
);
2460 beg_interval
= NULL
;
2462 /* normal_char and normal_backslash need `c'. */
2465 if (!(syntax
& RE_NO_BK_BRACES
))
2467 if (p
> pattern
&& p
[-1] == '\\')
2468 goto normal_backslash
;
2473 /* There is no way to specify the before_dot and after_dot
2474 operators. rms says this is ok. --karl */
2482 BUF_PUSH_2 (syntaxspec
, syntax_spec_code
[c
]);
2488 BUF_PUSH_2 (notsyntaxspec
, syntax_spec_code
[c
]);
2495 BUF_PUSH (wordchar
);
2501 BUF_PUSH (notwordchar
);
2514 BUF_PUSH (wordbound
);
2518 BUF_PUSH (notwordbound
);
2529 case '1': case '2': case '3': case '4': case '5':
2530 case '6': case '7': case '8': case '9':
2531 if (syntax
& RE_NO_BK_REFS
)
2537 FREE_STACK_RETURN (REG_ESUBREG
);
2539 /* Can't back reference to a subexpression if inside of it. */
2540 if (group_in_compile_stack (compile_stack
, c1
))
2544 BUF_PUSH_2 (duplicate
, c1
);
2550 if (syntax
& RE_BK_PLUS_QM
)
2553 goto normal_backslash
;
2557 /* You might think it would be useful for \ to mean
2558 not to translate; but if we don't translate it
2559 it will never match anything. */
2567 /* Expects the character in `c'. */
2569 /* If no exactn currently being built. */
2572 /* If last exactn not at current position. */
2573 || pending_exact
+ *pending_exact
+ 1 != b
2575 /* We have only one byte following the exactn for the count. */
2576 || *pending_exact
== (1 << BYTEWIDTH
) - 1
2578 /* If followed by a repetition operator. */
2579 || *p
== '*' || *p
== '^'
2580 || ((syntax
& RE_BK_PLUS_QM
)
2581 ? *p
== '\\' && (p
[1] == '+' || p
[1] == '?')
2582 : (*p
== '+' || *p
== '?'))
2583 || ((syntax
& RE_INTERVALS
)
2584 && ((syntax
& RE_NO_BK_BRACES
)
2586 : (p
[0] == '\\' && p
[1] == '{'))))
2588 /* Start building a new exactn. */
2592 BUF_PUSH_2 (exactn
, 0);
2593 pending_exact
= b
- 1;
2600 } /* while p != pend */
2603 /* Through the pattern now. */
2606 STORE_JUMP (jump_past_alt
, fixup_alt_jump
, b
);
2608 if (!COMPILE_STACK_EMPTY
)
2609 FREE_STACK_RETURN (REG_EPAREN
);
2611 /* If we don't want backtracking, force success
2612 the first time we reach the end of the compiled pattern. */
2613 if (syntax
& RE_NO_POSIX_BACKTRACKING
)
2616 free (compile_stack
.stack
);
2618 /* We have succeeded; set the length of the buffer. */
2619 bufp
->used
= b
- bufp
->buffer
;
2624 DEBUG_PRINT1 ("\nCompiled pattern: \n");
2625 print_compiled_pattern (bufp
);
2629 #ifndef MATCH_MAY_ALLOCATE
2630 /* Initialize the failure stack to the largest possible stack. This
2631 isn't necessary unless we're trying to avoid calling alloca in
2632 the search and match routines. */
2634 int num_regs
= bufp
->re_nsub
+ 1;
2636 /* Since DOUBLE_FAIL_STACK refuses to double only if the current size
2637 is strictly greater than re_max_failures, the largest possible stack
2638 is 2 * re_max_failures failure points. */
2639 if (fail_stack
.size
< (2 * re_max_failures
* MAX_FAILURE_ITEMS
))
2641 fail_stack
.size
= (2 * re_max_failures
* MAX_FAILURE_ITEMS
);
2644 if (! fail_stack
.stack
)
2646 = (fail_stack_elt_t
*) xmalloc (fail_stack
.size
2647 * sizeof (fail_stack_elt_t
));
2650 = (fail_stack_elt_t
*) xrealloc (fail_stack
.stack
,
2652 * sizeof (fail_stack_elt_t
)));
2653 #else /* not emacs */
2654 if (! fail_stack
.stack
)
2656 = (fail_stack_elt_t
*) malloc (fail_stack
.size
2657 * sizeof (fail_stack_elt_t
));
2660 = (fail_stack_elt_t
*) realloc (fail_stack
.stack
,
2662 * sizeof (fail_stack_elt_t
)));
2663 #endif /* not emacs */
2666 regex_grow_registers (num_regs
);
2668 #endif /* not MATCH_MAY_ALLOCATE */
2671 } /* regex_compile */
2673 /* Subroutines for `regex_compile'. */
2675 /* Store OP at LOC followed by two-byte integer parameter ARG. */
2678 store_op1 (op
, loc
, arg
)
2683 *loc
= (unsigned char) op
;
2684 STORE_NUMBER (loc
+ 1, arg
);
2688 /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
2691 store_op2 (op
, loc
, arg1
, arg2
)
2696 *loc
= (unsigned char) op
;
2697 STORE_NUMBER (loc
+ 1, arg1
);
2698 STORE_NUMBER (loc
+ 3, arg2
);
2702 /* Copy the bytes from LOC to END to open up three bytes of space at LOC
2703 for OP followed by two-byte integer parameter ARG. */
2706 insert_op1 (op
, loc
, arg
, end
)
2712 register unsigned char *pfrom
= end
;
2713 register unsigned char *pto
= end
+ 3;
2715 while (pfrom
!= loc
)
2718 store_op1 (op
, loc
, arg
);
2722 /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
2725 insert_op2 (op
, loc
, arg1
, arg2
, end
)
2731 register unsigned char *pfrom
= end
;
2732 register unsigned char *pto
= end
+ 5;
2734 while (pfrom
!= loc
)
2737 store_op2 (op
, loc
, arg1
, arg2
);
2741 /* P points to just after a ^ in PATTERN. Return true if that ^ comes
2742 after an alternative or a begin-subexpression. We assume there is at
2743 least one character before the ^. */
2746 at_begline_loc_p (pattern
, p
, syntax
)
2747 const char *pattern
, *p
;
2748 reg_syntax_t syntax
;
2750 const char *prev
= p
- 2;
2751 boolean prev_prev_backslash
= prev
> pattern
&& prev
[-1] == '\\';
2754 /* After a subexpression? */
2755 (*prev
== '(' && (syntax
& RE_NO_BK_PARENS
|| prev_prev_backslash
))
2756 /* After an alternative? */
2757 || (*prev
== '|' && (syntax
& RE_NO_BK_VBAR
|| prev_prev_backslash
));
2761 /* The dual of at_begline_loc_p. This one is for $. We assume there is
2762 at least one character after the $, i.e., `P < PEND'. */
2765 at_endline_loc_p (p
, pend
, syntax
)
2766 const char *p
, *pend
;
2769 const char *next
= p
;
2770 boolean next_backslash
= *next
== '\\';
2771 const char *next_next
= p
+ 1 < pend
? p
+ 1 : 0;
2774 /* Before a subexpression? */
2775 (syntax
& RE_NO_BK_PARENS
? *next
== ')'
2776 : next_backslash
&& next_next
&& *next_next
== ')')
2777 /* Before an alternative? */
2778 || (syntax
& RE_NO_BK_VBAR
? *next
== '|'
2779 : next_backslash
&& next_next
&& *next_next
== '|');
2783 /* Returns true if REGNUM is in one of COMPILE_STACK's elements and
2784 false if it's not. */
2787 group_in_compile_stack (compile_stack
, regnum
)
2788 compile_stack_type compile_stack
;
2793 for (this_element
= compile_stack
.avail
- 1;
2796 if (compile_stack
.stack
[this_element
].regnum
== regnum
)
2803 /* Read the ending character of a range (in a bracket expression) from the
2804 uncompiled pattern *P_PTR (which ends at PEND). We assume the
2805 starting character is in `P[-2]'. (`P[-1]' is the character `-'.)
2806 Then we set the translation of all bits between the starting and
2807 ending characters (inclusive) in the compiled pattern B.
2809 Return an error code.
2811 We use these short variable names so we can use the same macros as
2812 `regex_compile' itself. */
2814 static reg_errcode_t
2815 compile_range (p_ptr
, pend
, translate
, syntax
, b
)
2816 const char **p_ptr
, *pend
;
2818 reg_syntax_t syntax
;
2823 const char *p
= *p_ptr
;
2824 int range_start
, range_end
;
2829 /* Even though the pattern is a signed `char *', we need to fetch
2830 with unsigned char *'s; if the high bit of the pattern character
2831 is set, the range endpoints will be negative if we fetch using a
2834 We also want to fetch the endpoints without translating them; the
2835 appropriate translation is done in the bit-setting loop below. */
2836 /* The SVR4 compiler on the 3B2 had trouble with unsigned const char *. */
2837 range_start
= ((const unsigned char *) p
)[-2];
2838 range_end
= ((const unsigned char *) p
)[0];
2840 /* Have to increment the pointer into the pattern string, so the
2841 caller isn't still at the ending character. */
2844 /* If the start is after the end, the range is empty. */
2845 if (range_start
> range_end
)
2846 return syntax
& RE_NO_EMPTY_RANGES
? REG_ERANGE
: REG_NOERROR
;
2848 /* Here we see why `this_char' has to be larger than an `unsigned
2849 char' -- the range is inclusive, so if `range_end' == 0xff
2850 (assuming 8-bit characters), we would otherwise go into an infinite
2851 loop, since all characters <= 0xff. */
2852 for (this_char
= range_start
; this_char
<= range_end
; this_char
++)
2854 SET_LIST_BIT (TRANSLATE (this_char
));
2860 /* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
2861 BUFP. A fastmap records which of the (1 << BYTEWIDTH) possible
2862 characters can start a string that matches the pattern. This fastmap
2863 is used by re_search to skip quickly over impossible starting points.
2865 The caller must supply the address of a (1 << BYTEWIDTH)-byte data
2866 area as BUFP->fastmap.
2868 We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
2871 Returns 0 if we succeed, -2 if an internal error. */
2874 re_compile_fastmap (bufp
)
2875 struct re_pattern_buffer
*bufp
;
2878 #ifdef MATCH_MAY_ALLOCATE
2879 fail_stack_type fail_stack
;
2881 #ifndef REGEX_MALLOC
2884 /* We don't push any register information onto the failure stack. */
2885 unsigned num_regs
= 0;
2887 register char *fastmap
= bufp
->fastmap
;
2888 unsigned char *pattern
= bufp
->buffer
;
2889 unsigned long size
= bufp
->used
;
2890 unsigned char *p
= pattern
;
2891 register unsigned char *pend
= pattern
+ size
;
2893 /* This holds the pointer to the failure stack, when
2894 it is allocated relocatably. */
2895 fail_stack_elt_t
*failure_stack_ptr
;
2897 /* Assume that each path through the pattern can be null until
2898 proven otherwise. We set this false at the bottom of switch
2899 statement, to which we get only if a particular path doesn't
2900 match the empty string. */
2901 boolean path_can_be_null
= true;
2903 /* We aren't doing a `succeed_n' to begin with. */
2904 boolean succeed_n_p
= false;
2906 assert (fastmap
!= NULL
&& p
!= NULL
);
2909 bzero (fastmap
, 1 << BYTEWIDTH
); /* Assume nothing's valid. */
2910 bufp
->fastmap_accurate
= 1; /* It will be when we're done. */
2911 bufp
->can_be_null
= 0;
2915 if (p
== pend
|| *p
== succeed
)
2917 /* We have reached the (effective) end of pattern. */
2918 if (!FAIL_STACK_EMPTY ())
2920 bufp
->can_be_null
|= path_can_be_null
;
2922 /* Reset for next path. */
2923 path_can_be_null
= true;
2925 p
= fail_stack
.stack
[--fail_stack
.avail
].pointer
;
2933 /* We should never be about to go beyond the end of the pattern. */
2936 switch (SWITCH_ENUM_CAST ((re_opcode_t
) *p
++))
2939 /* I guess the idea here is to simply not bother with a fastmap
2940 if a backreference is used, since it's too hard to figure out
2941 the fastmap for the corresponding group. Setting
2942 `can_be_null' stops `re_search_2' from using the fastmap, so
2943 that is all we do. */
2945 bufp
->can_be_null
= 1;
2949 /* Following are the cases which match a character. These end
2958 for (j
= *p
++ * BYTEWIDTH
- 1; j
>= 0; j
--)
2959 if (p
[j
/ BYTEWIDTH
] & (1 << (j
% BYTEWIDTH
)))
2965 /* Chars beyond end of map must be allowed. */
2966 for (j
= *p
* BYTEWIDTH
; j
< (1 << BYTEWIDTH
); j
++)
2969 for (j
= *p
++ * BYTEWIDTH
- 1; j
>= 0; j
--)
2970 if (!(p
[j
/ BYTEWIDTH
] & (1 << (j
% BYTEWIDTH
))))
2976 for (j
= 0; j
< (1 << BYTEWIDTH
); j
++)
2977 if (SYNTAX (j
) == Sword
)
2983 for (j
= 0; j
< (1 << BYTEWIDTH
); j
++)
2984 if (SYNTAX (j
) != Sword
)
2991 int fastmap_newline
= fastmap
['\n'];
2993 /* `.' matches anything ... */
2994 for (j
= 0; j
< (1 << BYTEWIDTH
); j
++)
2997 /* ... except perhaps newline. */
2998 if (!(bufp
->syntax
& RE_DOT_NEWLINE
))
2999 fastmap
['\n'] = fastmap_newline
;
3001 /* Return if we have already set `can_be_null'; if we have,
3002 then the fastmap is irrelevant. Something's wrong here. */
3003 else if (bufp
->can_be_null
)
3006 /* Otherwise, have to check alternative paths. */
3013 for (j
= 0; j
< (1 << BYTEWIDTH
); j
++)
3014 if (SYNTAX (j
) == (enum syntaxcode
) k
)
3021 for (j
= 0; j
< (1 << BYTEWIDTH
); j
++)
3022 if (SYNTAX (j
) != (enum syntaxcode
) k
)
3027 /* All cases after this match the empty string. These end with
3035 #endif /* not emacs */
3047 case push_dummy_failure
:
3052 case pop_failure_jump
:
3053 case maybe_pop_jump
:
3056 case dummy_failure_jump
:
3057 EXTRACT_NUMBER_AND_INCR (j
, p
);
3062 /* Jump backward implies we just went through the body of a
3063 loop and matched nothing. Opcode jumped to should be
3064 `on_failure_jump' or `succeed_n'. Just treat it like an
3065 ordinary jump. For a * loop, it has pushed its failure
3066 point already; if so, discard that as redundant. */
3067 if ((re_opcode_t
) *p
!= on_failure_jump
3068 && (re_opcode_t
) *p
!= succeed_n
)
3072 EXTRACT_NUMBER_AND_INCR (j
, p
);
3075 /* If what's on the stack is where we are now, pop it. */
3076 if (!FAIL_STACK_EMPTY ()
3077 && fail_stack
.stack
[fail_stack
.avail
- 1].pointer
== p
)
3083 case on_failure_jump
:
3084 case on_failure_keep_string_jump
:
3085 handle_on_failure_jump
:
3086 EXTRACT_NUMBER_AND_INCR (j
, p
);
3088 /* For some patterns, e.g., `(a?)?', `p+j' here points to the
3089 end of the pattern. We don't want to push such a point,
3090 since when we restore it above, entering the switch will
3091 increment `p' past the end of the pattern. We don't need
3092 to push such a point since we obviously won't find any more
3093 fastmap entries beyond `pend'. Such a pattern can match
3094 the null string, though. */
3097 if (!PUSH_PATTERN_OP (p
+ j
, fail_stack
))
3099 RESET_FAIL_STACK ();
3104 bufp
->can_be_null
= 1;
3108 EXTRACT_NUMBER_AND_INCR (k
, p
); /* Skip the n. */
3109 succeed_n_p
= false;
3116 /* Get to the number of times to succeed. */
3119 /* Increment p past the n for when k != 0. */
3120 EXTRACT_NUMBER_AND_INCR (k
, p
);
3124 succeed_n_p
= true; /* Spaghetti code alert. */
3125 goto handle_on_failure_jump
;
3142 abort (); /* We have listed all the cases. */
3145 /* Getting here means we have found the possible starting
3146 characters for one path of the pattern -- and that the empty
3147 string does not match. We need not follow this path further.
3148 Instead, look at the next alternative (remembered on the
3149 stack), or quit if no more. The test at the top of the loop
3150 does these things. */
3151 path_can_be_null
= false;
3155 /* Set `can_be_null' for the last path (also the first path, if the
3156 pattern is empty). */
3157 bufp
->can_be_null
|= path_can_be_null
;
3160 RESET_FAIL_STACK ();
3162 } /* re_compile_fastmap */
3164 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
3165 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
3166 this memory for recording register information. STARTS and ENDS
3167 must be allocated using the malloc library routine, and must each
3168 be at least NUM_REGS * sizeof (regoff_t) bytes long.
3170 If NUM_REGS == 0, then subsequent matches should allocate their own
3173 Unless this function is called, the first search or match using
3174 PATTERN_BUFFER will allocate its own register data, without
3175 freeing the old data. */
3178 re_set_registers (bufp
, regs
, num_regs
, starts
, ends
)
3179 struct re_pattern_buffer
*bufp
;
3180 struct re_registers
*regs
;
3182 regoff_t
*starts
, *ends
;
3186 bufp
->regs_allocated
= REGS_REALLOCATE
;
3187 regs
->num_regs
= num_regs
;
3188 regs
->start
= starts
;
3193 bufp
->regs_allocated
= REGS_UNALLOCATED
;
3195 regs
->start
= regs
->end
= (regoff_t
*) 0;
3199 /* Searching routines. */
3201 /* Like re_search_2, below, but only one string is specified, and
3202 doesn't let you say where to stop matching. */
3205 re_search (bufp
, string
, size
, startpos
, range
, regs
)
3206 struct re_pattern_buffer
*bufp
;
3208 int size
, startpos
, range
;
3209 struct re_registers
*regs
;
3211 return re_search_2 (bufp
, NULL
, 0, string
, size
, startpos
, range
,
3216 /* Using the compiled pattern in BUFP->buffer, first tries to match the
3217 virtual concatenation of STRING1 and STRING2, starting first at index
3218 STARTPOS, then at STARTPOS + 1, and so on.
3220 STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
3222 RANGE is how far to scan while trying to match. RANGE = 0 means try
3223 only at STARTPOS; in general, the last start tried is STARTPOS +
3226 In REGS, return the indices of the virtual concatenation of STRING1
3227 and STRING2 that matched the entire BUFP->buffer and its contained
3230 Do not consider matching one past the index STOP in the virtual
3231 concatenation of STRING1 and STRING2.
3233 We return either the position in the strings at which the match was
3234 found, -1 if no match, or -2 if error (such as failure
3238 re_search_2 (bufp
, string1
, size1
, string2
, size2
, startpos
, range
, regs
, stop
)
3239 struct re_pattern_buffer
*bufp
;
3240 const char *string1
, *string2
;
3244 struct re_registers
*regs
;
3248 register char *fastmap
= bufp
->fastmap
;
3249 register char *translate
= bufp
->translate
;
3250 int total_size
= size1
+ size2
;
3251 int endpos
= startpos
+ range
;
3253 /* Check for out-of-range STARTPOS. */
3254 if (startpos
< 0 || startpos
> total_size
)
3257 /* Fix up RANGE if it might eventually take us outside
3258 the virtual concatenation of STRING1 and STRING2. */
3260 range
= -1 - startpos
;
3261 else if (endpos
> total_size
)
3262 range
= total_size
- startpos
;
3264 /* If the search isn't to be a backwards one, don't waste time in a
3265 search for a pattern that must be anchored. */
3266 if (bufp
->used
> 0 && (re_opcode_t
) bufp
->buffer
[0] == begbuf
&& range
> 0)
3274 /* Update the fastmap now if not correct already. */
3275 if (fastmap
&& !bufp
->fastmap_accurate
)
3276 if (re_compile_fastmap (bufp
) == -2)
3279 /* Loop through the string, looking for a place to start matching. */
3282 /* If a fastmap is supplied, skip quickly over characters that
3283 cannot be the start of a match. If the pattern can match the
3284 null string, however, we don't need to skip characters; we want
3285 the first null string. */
3286 if (fastmap
&& startpos
< total_size
&& !bufp
->can_be_null
)
3288 if (range
> 0) /* Searching forwards. */
3290 register const char *d
;
3291 register int lim
= 0;
3294 if (startpos
< size1
&& startpos
+ range
>= size1
)
3295 lim
= range
- (size1
- startpos
);
3297 d
= (startpos
>= size1
? string2
- size1
: string1
) + startpos
;
3299 /* Written out as an if-else to avoid testing `translate'
3303 && !fastmap
[(unsigned char)
3304 translate
[(unsigned char) *d
++]])
3307 while (range
> lim
&& !fastmap
[(unsigned char) *d
++])
3310 startpos
+= irange
- range
;
3312 else /* Searching backwards. */
3314 register char c
= (size1
== 0 || startpos
>= size1
3315 ? string2
[startpos
- size1
]
3316 : string1
[startpos
]);
3318 if (!fastmap
[(unsigned char) TRANSLATE (c
)])
3323 /* If can't match the null string, and that's all we have left, fail. */
3324 if (range
>= 0 && startpos
== total_size
&& fastmap
3325 && !bufp
->can_be_null
)
3328 val
= re_match_2_internal (bufp
, string1
, size1
, string2
, size2
,
3329 startpos
, regs
, stop
);
3330 #ifndef REGEX_MALLOC
3359 /* Declarations and macros for re_match_2. */
3361 static int bcmp_translate ();
3362 static boolean
alt_match_null_string_p (),
3363 common_op_match_null_string_p (),
3364 group_match_null_string_p ();
3366 /* This converts PTR, a pointer into one of the search strings `string1'
3367 and `string2' into an offset from the beginning of that string. */
3368 #define POINTER_TO_OFFSET(ptr) \
3369 (FIRST_STRING_P (ptr) \
3370 ? ((regoff_t) ((ptr) - string1)) \
3371 : ((regoff_t) ((ptr) - string2 + size1)))
3373 /* Macros for dealing with the split strings in re_match_2. */
3375 #define MATCHING_IN_FIRST_STRING (dend == end_match_1)
3377 /* Call before fetching a character with *d. This switches over to
3378 string2 if necessary. */
3379 #define PREFETCH() \
3382 /* End of string2 => fail. */ \
3383 if (dend == end_match_2) \
3385 /* End of string1 => advance to string2. */ \
3387 dend = end_match_2; \
3391 /* Test if at very beginning or at very end of the virtual concatenation
3392 of `string1' and `string2'. If only one string, it's `string2'. */
3393 #define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
3394 #define AT_STRINGS_END(d) ((d) == end2)
3397 /* Test if D points to a character which is word-constituent. We have
3398 two special cases to check for: if past the end of string1, look at
3399 the first character in string2; and if before the beginning of
3400 string2, look at the last character in string1. */
3401 #define WORDCHAR_P(d) \
3402 (SYNTAX ((d) == end1 ? *string2 \
3403 : (d) == string2 - 1 ? *(end1 - 1) : *(d)) \
3406 /* Test if the character before D and the one at D differ with respect
3407 to being word-constituent. */
3408 #define AT_WORD_BOUNDARY(d) \
3409 (AT_STRINGS_BEG (d) || AT_STRINGS_END (d) \
3410 || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
3413 /* Free everything we malloc. */
3414 #ifdef MATCH_MAY_ALLOCATE
3415 #define FREE_VAR(var) if (var) REGEX_FREE (var); var = NULL
3416 #define FREE_VARIABLES() \
3418 REGEX_FREE_STACK (fail_stack.stack); \
3419 FREE_VAR (regstart); \
3420 FREE_VAR (regend); \
3421 FREE_VAR (old_regstart); \
3422 FREE_VAR (old_regend); \
3423 FREE_VAR (best_regstart); \
3424 FREE_VAR (best_regend); \
3425 FREE_VAR (reg_info); \
3426 FREE_VAR (reg_dummy); \
3427 FREE_VAR (reg_info_dummy); \
3430 #define FREE_VARIABLES() ((void)0) /* Do nothing! But inhibit gcc warning. */
3431 #endif /* not MATCH_MAY_ALLOCATE */
3433 /* These values must meet several constraints. They must not be valid
3434 register values; since we have a limit of 255 registers (because
3435 we use only one byte in the pattern for the register number), we can
3436 use numbers larger than 255. They must differ by 1, because of
3437 NUM_FAILURE_ITEMS above. And the value for the lowest register must
3438 be larger than the value for the highest register, so we do not try
3439 to actually save any registers when none are active. */
3440 #define NO_HIGHEST_ACTIVE_REG (1 << BYTEWIDTH)
3441 #define NO_LOWEST_ACTIVE_REG (NO_HIGHEST_ACTIVE_REG + 1)
3443 /* Matching routines. */
3445 #ifndef emacs /* Emacs never uses this. */
3446 /* re_match is like re_match_2 except it takes only a single string. */
3449 re_match (bufp
, string
, size
, pos
, regs
)
3450 struct re_pattern_buffer
*bufp
;
3453 struct re_registers
*regs
;
3455 int result
= re_match_2_internal (bufp
, NULL
, 0, string
, size
,
3460 #endif /* not emacs */
3463 /* re_match_2 matches the compiled pattern in BUFP against the
3464 the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
3465 and SIZE2, respectively). We start matching at POS, and stop
3468 If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
3469 store offsets for the substring each group matched in REGS. See the
3470 documentation for exactly how many groups we fill.
3472 We return -1 if no match, -2 if an internal error (such as the
3473 failure stack overflowing). Otherwise, we return the length of the
3474 matched substring. */
3477 re_match_2 (bufp
, string1
, size1
, string2
, size2
, pos
, regs
, stop
)
3478 struct re_pattern_buffer
*bufp
;
3479 const char *string1
, *string2
;
3482 struct re_registers
*regs
;
3485 int result
= re_match_2_internal (bufp
, string1
, size1
, string2
, size2
,
3491 /* This is a separate function so that we can force an alloca cleanup
3494 re_match_2_internal (bufp
, string1
, size1
, string2
, size2
, pos
, regs
, stop
)
3495 struct re_pattern_buffer
*bufp
;
3496 const char *string1
, *string2
;
3499 struct re_registers
*regs
;
3502 /* General temporaries. */
3506 /* Just past the end of the corresponding string. */
3507 const char *end1
, *end2
;
3509 /* Pointers into string1 and string2, just past the last characters in
3510 each to consider matching. */
3511 const char *end_match_1
, *end_match_2
;
3513 /* Where we are in the data, and the end of the current string. */
3514 const char *d
, *dend
;
3516 /* Where we are in the pattern, and the end of the pattern. */
3517 unsigned char *p
= bufp
->buffer
;
3518 register unsigned char *pend
= p
+ bufp
->used
;
3520 /* Mark the opcode just after a start_memory, so we can test for an
3521 empty subpattern when we get to the stop_memory. */
3522 unsigned char *just_past_start_mem
= 0;
3524 /* We use this to map every character in the string. */
3525 char *translate
= bufp
->translate
;
3527 /* Failure point stack. Each place that can handle a failure further
3528 down the line pushes a failure point on this stack. It consists of
3529 restart, regend, and reg_info for all registers corresponding to
3530 the subexpressions we're currently inside, plus the number of such
3531 registers, and, finally, two char *'s. The first char * is where
3532 to resume scanning the pattern; the second one is where to resume
3533 scanning the strings. If the latter is zero, the failure point is
3534 a ``dummy''; if a failure happens and the failure point is a dummy,
3535 it gets discarded and the next next one is tried. */
3536 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
3537 fail_stack_type fail_stack
;
3540 static unsigned failure_id
= 0;
3541 unsigned nfailure_points_pushed
= 0, nfailure_points_popped
= 0;
3544 /* This holds the pointer to the failure stack, when
3545 it is allocated relocatably. */
3546 fail_stack_elt_t
*failure_stack_ptr
;
3548 /* We fill all the registers internally, independent of what we
3549 return, for use in backreferences. The number here includes
3550 an element for register zero. */
3551 unsigned num_regs
= bufp
->re_nsub
+ 1;
3553 /* The currently active registers. */
3554 unsigned lowest_active_reg
= NO_LOWEST_ACTIVE_REG
;
3555 unsigned highest_active_reg
= NO_HIGHEST_ACTIVE_REG
;
3557 /* Information on the contents of registers. These are pointers into
3558 the input strings; they record just what was matched (on this
3559 attempt) by a subexpression part of the pattern, that is, the
3560 regnum-th regstart pointer points to where in the pattern we began
3561 matching and the regnum-th regend points to right after where we
3562 stopped matching the regnum-th subexpression. (The zeroth register
3563 keeps track of what the whole pattern matches.) */
3564 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3565 const char **regstart
, **regend
;
3568 /* If a group that's operated upon by a repetition operator fails to
3569 match anything, then the register for its start will need to be
3570 restored because it will have been set to wherever in the string we
3571 are when we last see its open-group operator. Similarly for a
3573 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3574 const char **old_regstart
, **old_regend
;
3577 /* The is_active field of reg_info helps us keep track of which (possibly
3578 nested) subexpressions we are currently in. The matched_something
3579 field of reg_info[reg_num] helps us tell whether or not we have
3580 matched any of the pattern so far this time through the reg_num-th
3581 subexpression. These two fields get reset each time through any
3582 loop their register is in. */
3583 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
3584 register_info_type
*reg_info
;
3587 /* The following record the register info as found in the above
3588 variables when we find a match better than any we've seen before.
3589 This happens as we backtrack through the failure points, which in
3590 turn happens only if we have not yet matched the entire string. */
3591 unsigned best_regs_set
= false;
3592 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3593 const char **best_regstart
, **best_regend
;
3596 /* Logically, this is `best_regend[0]'. But we don't want to have to
3597 allocate space for that if we're not allocating space for anything
3598 else (see below). Also, we never need info about register 0 for
3599 any of the other register vectors, and it seems rather a kludge to
3600 treat `best_regend' differently than the rest. So we keep track of
3601 the end of the best match so far in a separate variable. We
3602 initialize this to NULL so that when we backtrack the first time
3603 and need to test it, it's not garbage. */
3604 const char *match_end
= NULL
;
3606 /* This helps SET_REGS_MATCHED avoid doing redundant work. */
3607 int set_regs_matched_done
= 0;
3609 /* Used when we pop values we don't care about. */
3610 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3611 const char **reg_dummy
;
3612 register_info_type
*reg_info_dummy
;
3616 /* Counts the total number of registers pushed. */
3617 unsigned num_regs_pushed
= 0;
3620 DEBUG_PRINT1 ("\n\nEntering re_match_2.\n");
3624 #ifdef MATCH_MAY_ALLOCATE
3625 /* Do not bother to initialize all the register variables if there are
3626 no groups in the pattern, as it takes a fair amount of time. If
3627 there are groups, we include space for register 0 (the whole
3628 pattern), even though we never use it, since it simplifies the
3629 array indexing. We should fix this. */
3632 regstart
= REGEX_TALLOC (num_regs
, const char *);
3633 regend
= REGEX_TALLOC (num_regs
, const char *);
3634 old_regstart
= REGEX_TALLOC (num_regs
, const char *);
3635 old_regend
= REGEX_TALLOC (num_regs
, const char *);
3636 best_regstart
= REGEX_TALLOC (num_regs
, const char *);
3637 best_regend
= REGEX_TALLOC (num_regs
, const char *);
3638 reg_info
= REGEX_TALLOC (num_regs
, register_info_type
);
3639 reg_dummy
= REGEX_TALLOC (num_regs
, const char *);
3640 reg_info_dummy
= REGEX_TALLOC (num_regs
, register_info_type
);
3642 if (!(regstart
&& regend
&& old_regstart
&& old_regend
&& reg_info
3643 && best_regstart
&& best_regend
&& reg_dummy
&& reg_info_dummy
))
3651 /* We must initialize all our variables to NULL, so that
3652 `FREE_VARIABLES' doesn't try to free them. */
3653 regstart
= regend
= old_regstart
= old_regend
= best_regstart
3654 = best_regend
= reg_dummy
= NULL
;
3655 reg_info
= reg_info_dummy
= (register_info_type
*) NULL
;
3657 #endif /* MATCH_MAY_ALLOCATE */
3659 /* The starting position is bogus. */
3660 if (pos
< 0 || pos
> size1
+ size2
)
3666 /* Initialize subexpression text positions to -1 to mark ones that no
3667 start_memory/stop_memory has been seen for. Also initialize the
3668 register information struct. */
3669 for (mcnt
= 1; mcnt
< num_regs
; mcnt
++)
3671 regstart
[mcnt
] = regend
[mcnt
]
3672 = old_regstart
[mcnt
] = old_regend
[mcnt
] = REG_UNSET_VALUE
;
3674 REG_MATCH_NULL_STRING_P (reg_info
[mcnt
]) = MATCH_NULL_UNSET_VALUE
;
3675 IS_ACTIVE (reg_info
[mcnt
]) = 0;
3676 MATCHED_SOMETHING (reg_info
[mcnt
]) = 0;
3677 EVER_MATCHED_SOMETHING (reg_info
[mcnt
]) = 0;
3680 /* We move `string1' into `string2' if the latter's empty -- but not if
3681 `string1' is null. */
3682 if (size2
== 0 && string1
!= NULL
)
3689 end1
= string1
+ size1
;
3690 end2
= string2
+ size2
;
3692 /* Compute where to stop matching, within the two strings. */
3695 end_match_1
= string1
+ stop
;
3696 end_match_2
= string2
;
3701 end_match_2
= string2
+ stop
- size1
;
3704 /* `p' scans through the pattern as `d' scans through the data.
3705 `dend' is the end of the input string that `d' points within. `d'
3706 is advanced into the following input string whenever necessary, but
3707 this happens before fetching; therefore, at the beginning of the
3708 loop, `d' can be pointing at the end of a string, but it cannot
3710 if (size1
> 0 && pos
<= size1
)
3717 d
= string2
+ pos
- size1
;
3721 DEBUG_PRINT1 ("The compiled pattern is: ");
3722 DEBUG_PRINT_COMPILED_PATTERN (bufp
, p
, pend
);
3723 DEBUG_PRINT1 ("The string to match is: `");
3724 DEBUG_PRINT_DOUBLE_STRING (d
, string1
, size1
, string2
, size2
);
3725 DEBUG_PRINT1 ("'\n");
3727 /* This loops over pattern commands. It exits by returning from the
3728 function if the match is complete, or it drops through if the match
3729 fails at this starting point in the input data. */
3732 DEBUG_PRINT2 ("\n0x%x: ", p
);
3735 { /* End of pattern means we might have succeeded. */
3736 DEBUG_PRINT1 ("end of pattern ... ");
3738 /* If we haven't matched the entire string, and we want the
3739 longest match, try backtracking. */
3740 if (d
!= end_match_2
)
3742 /* 1 if this match ends in the same string (string1 or string2)
3743 as the best previous match. */
3744 boolean same_str_p
= (FIRST_STRING_P (match_end
)
3745 == MATCHING_IN_FIRST_STRING
);
3746 /* 1 if this match is the best seen so far. */
3747 boolean best_match_p
;
3749 /* AIX compiler got confused when this was combined
3750 with the previous declaration. */
3752 best_match_p
= d
> match_end
;
3754 best_match_p
= !MATCHING_IN_FIRST_STRING
;
3756 DEBUG_PRINT1 ("backtracking.\n");
3758 if (!FAIL_STACK_EMPTY ())
3759 { /* More failure points to try. */
3761 /* If exceeds best match so far, save it. */
3762 if (!best_regs_set
|| best_match_p
)
3764 best_regs_set
= true;
3767 DEBUG_PRINT1 ("\nSAVING match as best so far.\n");
3769 for (mcnt
= 1; mcnt
< num_regs
; mcnt
++)
3771 best_regstart
[mcnt
] = regstart
[mcnt
];
3772 best_regend
[mcnt
] = regend
[mcnt
];
3778 /* If no failure points, don't restore garbage. And if
3779 last match is real best match, don't restore second
3781 else if (best_regs_set
&& !best_match_p
)
3784 /* Restore best match. It may happen that `dend ==
3785 end_match_1' while the restored d is in string2.
3786 For example, the pattern `x.*y.*z' against the
3787 strings `x-' and `y-z-', if the two strings are
3788 not consecutive in memory. */
3789 DEBUG_PRINT1 ("Restoring best registers.\n");
3792 dend
= ((d
>= string1
&& d
<= end1
)
3793 ? end_match_1
: end_match_2
);
3795 for (mcnt
= 1; mcnt
< num_regs
; mcnt
++)
3797 regstart
[mcnt
] = best_regstart
[mcnt
];
3798 regend
[mcnt
] = best_regend
[mcnt
];
3801 } /* d != end_match_2 */
3804 DEBUG_PRINT1 ("Accepting match.\n");
3806 /* If caller wants register contents data back, do it. */
3807 if (regs
&& !bufp
->no_sub
)
3809 /* Have the register data arrays been allocated? */
3810 if (bufp
->regs_allocated
== REGS_UNALLOCATED
)
3811 { /* No. So allocate them with malloc. We need one
3812 extra element beyond `num_regs' for the `-1' marker
3814 regs
->num_regs
= MAX (RE_NREGS
, num_regs
+ 1);
3815 regs
->start
= TALLOC (regs
->num_regs
, regoff_t
);
3816 regs
->end
= TALLOC (regs
->num_regs
, regoff_t
);
3817 if (regs
->start
== NULL
|| regs
->end
== NULL
)
3822 bufp
->regs_allocated
= REGS_REALLOCATE
;
3824 else if (bufp
->regs_allocated
== REGS_REALLOCATE
)
3825 { /* Yes. If we need more elements than were already
3826 allocated, reallocate them. If we need fewer, just
3828 if (regs
->num_regs
< num_regs
+ 1)
3830 regs
->num_regs
= num_regs
+ 1;
3831 RETALLOC (regs
->start
, regs
->num_regs
, regoff_t
);
3832 RETALLOC (regs
->end
, regs
->num_regs
, regoff_t
);
3833 if (regs
->start
== NULL
|| regs
->end
== NULL
)
3842 /* These braces fend off a "empty body in an else-statement"
3843 warning under GCC when assert expands to nothing. */
3844 assert (bufp
->regs_allocated
== REGS_FIXED
);
3847 /* Convert the pointer data in `regstart' and `regend' to
3848 indices. Register zero has to be set differently,
3849 since we haven't kept track of any info for it. */
3850 if (regs
->num_regs
> 0)
3852 regs
->start
[0] = pos
;
3853 regs
->end
[0] = (MATCHING_IN_FIRST_STRING
3854 ? ((regoff_t
) (d
- string1
))
3855 : ((regoff_t
) (d
- string2
+ size1
)));
3858 /* Go through the first `min (num_regs, regs->num_regs)'
3859 registers, since that is all we initialized. */
3860 for (mcnt
= 1; mcnt
< MIN (num_regs
, regs
->num_regs
); mcnt
++)
3862 if (REG_UNSET (regstart
[mcnt
]) || REG_UNSET (regend
[mcnt
]))
3863 regs
->start
[mcnt
] = regs
->end
[mcnt
] = -1;
3867 = (regoff_t
) POINTER_TO_OFFSET (regstart
[mcnt
]);
3869 = (regoff_t
) POINTER_TO_OFFSET (regend
[mcnt
]);
3873 /* If the regs structure we return has more elements than
3874 were in the pattern, set the extra elements to -1. If
3875 we (re)allocated the registers, this is the case,
3876 because we always allocate enough to have at least one
3878 for (mcnt
= num_regs
; mcnt
< regs
->num_regs
; mcnt
++)
3879 regs
->start
[mcnt
] = regs
->end
[mcnt
] = -1;
3880 } /* regs && !bufp->no_sub */
3882 DEBUG_PRINT4 ("%u failure points pushed, %u popped (%u remain).\n",
3883 nfailure_points_pushed
, nfailure_points_popped
,
3884 nfailure_points_pushed
- nfailure_points_popped
);
3885 DEBUG_PRINT2 ("%u registers pushed.\n", num_regs_pushed
);
3887 mcnt
= d
- pos
- (MATCHING_IN_FIRST_STRING
3891 DEBUG_PRINT2 ("Returning %d from re_match_2.\n", mcnt
);
3897 /* Otherwise match next pattern command. */
3898 switch (SWITCH_ENUM_CAST ((re_opcode_t
) *p
++))
3900 /* Ignore these. Used to ignore the n of succeed_n's which
3901 currently have n == 0. */
3903 DEBUG_PRINT1 ("EXECUTING no_op.\n");
3907 DEBUG_PRINT1 ("EXECUTING succeed.\n");
3910 /* Match the next n pattern characters exactly. The following
3911 byte in the pattern defines n, and the n bytes after that
3912 are the characters to match. */
3915 DEBUG_PRINT2 ("EXECUTING exactn %d.\n", mcnt
);
3917 /* This is written out as an if-else so we don't waste time
3918 testing `translate' inside the loop. */
3924 if (translate
[(unsigned char) *d
++] != (char) *p
++)
3934 if (*d
++ != (char) *p
++) goto fail
;
3938 SET_REGS_MATCHED ();
3942 /* Match any character except possibly a newline or a null. */
3944 DEBUG_PRINT1 ("EXECUTING anychar.\n");
3948 if ((!(bufp
->syntax
& RE_DOT_NEWLINE
) && TRANSLATE (*d
) == '\n')
3949 || (bufp
->syntax
& RE_DOT_NOT_NULL
&& TRANSLATE (*d
) == '\000'))
3952 SET_REGS_MATCHED ();
3953 DEBUG_PRINT2 (" Matched `%d'.\n", *d
);
3961 register unsigned char c
;
3962 boolean
not = (re_opcode_t
) *(p
- 1) == charset_not
;
3964 DEBUG_PRINT2 ("EXECUTING charset%s.\n", not ? "_not" : "");
3967 c
= TRANSLATE (*d
); /* The character to match. */
3969 /* Cast to `unsigned' instead of `unsigned char' in case the
3970 bit list is a full 32 bytes long. */
3971 if (c
< (unsigned) (*p
* BYTEWIDTH
)
3972 && p
[1 + c
/ BYTEWIDTH
] & (1 << (c
% BYTEWIDTH
)))
3977 if (!not) goto fail
;
3979 SET_REGS_MATCHED ();
3985 /* The beginning of a group is represented by start_memory.
3986 The arguments are the register number in the next byte, and the
3987 number of groups inner to this one in the next. The text
3988 matched within the group is recorded (in the internal
3989 registers data structure) under the register number. */
3991 DEBUG_PRINT3 ("EXECUTING start_memory %d (%d):\n", *p
, p
[1]);
3993 /* Find out if this group can match the empty string. */
3994 p1
= p
; /* To send to group_match_null_string_p. */
3996 if (REG_MATCH_NULL_STRING_P (reg_info
[*p
]) == MATCH_NULL_UNSET_VALUE
)
3997 REG_MATCH_NULL_STRING_P (reg_info
[*p
])
3998 = group_match_null_string_p (&p1
, pend
, reg_info
);
4000 /* Save the position in the string where we were the last time
4001 we were at this open-group operator in case the group is
4002 operated upon by a repetition operator, e.g., with `(a*)*b'
4003 against `ab'; then we want to ignore where we are now in
4004 the string in case this attempt to match fails. */
4005 old_regstart
[*p
] = REG_MATCH_NULL_STRING_P (reg_info
[*p
])
4006 ? REG_UNSET (regstart
[*p
]) ? d
: regstart
[*p
]
4008 DEBUG_PRINT2 (" old_regstart: %d\n",
4009 POINTER_TO_OFFSET (old_regstart
[*p
]));
4012 DEBUG_PRINT2 (" regstart: %d\n", POINTER_TO_OFFSET (regstart
[*p
]));
4014 IS_ACTIVE (reg_info
[*p
]) = 1;
4015 MATCHED_SOMETHING (reg_info
[*p
]) = 0;
4017 /* Clear this whenever we change the register activity status. */
4018 set_regs_matched_done
= 0;
4020 /* This is the new highest active register. */
4021 highest_active_reg
= *p
;
4023 /* If nothing was active before, this is the new lowest active
4025 if (lowest_active_reg
== NO_LOWEST_ACTIVE_REG
)
4026 lowest_active_reg
= *p
;
4028 /* Move past the register number and inner group count. */
4030 just_past_start_mem
= p
;
4035 /* The stop_memory opcode represents the end of a group. Its
4036 arguments are the same as start_memory's: the register
4037 number, and the number of inner groups. */
4039 DEBUG_PRINT3 ("EXECUTING stop_memory %d (%d):\n", *p
, p
[1]);
4041 /* We need to save the string position the last time we were at
4042 this close-group operator in case the group is operated
4043 upon by a repetition operator, e.g., with `((a*)*(b*)*)*'
4044 against `aba'; then we want to ignore where we are now in
4045 the string in case this attempt to match fails. */
4046 old_regend
[*p
] = REG_MATCH_NULL_STRING_P (reg_info
[*p
])
4047 ? REG_UNSET (regend
[*p
]) ? d
: regend
[*p
]
4049 DEBUG_PRINT2 (" old_regend: %d\n",
4050 POINTER_TO_OFFSET (old_regend
[*p
]));
4053 DEBUG_PRINT2 (" regend: %d\n", POINTER_TO_OFFSET (regend
[*p
]));
4055 /* This register isn't active anymore. */
4056 IS_ACTIVE (reg_info
[*p
]) = 0;
4058 /* Clear this whenever we change the register activity status. */
4059 set_regs_matched_done
= 0;
4061 /* If this was the only register active, nothing is active
4063 if (lowest_active_reg
== highest_active_reg
)
4065 lowest_active_reg
= NO_LOWEST_ACTIVE_REG
;
4066 highest_active_reg
= NO_HIGHEST_ACTIVE_REG
;
4069 { /* We must scan for the new highest active register, since
4070 it isn't necessarily one less than now: consider
4071 (a(b)c(d(e)f)g). When group 3 ends, after the f), the
4072 new highest active register is 1. */
4073 unsigned char r
= *p
- 1;
4074 while (r
> 0 && !IS_ACTIVE (reg_info
[r
]))
4077 /* If we end up at register zero, that means that we saved
4078 the registers as the result of an `on_failure_jump', not
4079 a `start_memory', and we jumped to past the innermost
4080 `stop_memory'. For example, in ((.)*) we save
4081 registers 1 and 2 as a result of the *, but when we pop
4082 back to the second ), we are at the stop_memory 1.
4083 Thus, nothing is active. */
4086 lowest_active_reg
= NO_LOWEST_ACTIVE_REG
;
4087 highest_active_reg
= NO_HIGHEST_ACTIVE_REG
;
4090 highest_active_reg
= r
;
4093 /* If just failed to match something this time around with a
4094 group that's operated on by a repetition operator, try to
4095 force exit from the ``loop'', and restore the register
4096 information for this group that we had before trying this
4098 if ((!MATCHED_SOMETHING (reg_info
[*p
])
4099 || just_past_start_mem
== p
- 1)
4102 boolean is_a_jump_n
= false;
4106 switch ((re_opcode_t
) *p1
++)
4110 case pop_failure_jump
:
4111 case maybe_pop_jump
:
4113 case dummy_failure_jump
:
4114 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
4124 /* If the next operation is a jump backwards in the pattern
4125 to an on_failure_jump right before the start_memory
4126 corresponding to this stop_memory, exit from the loop
4127 by forcing a failure after pushing on the stack the
4128 on_failure_jump's jump in the pattern, and d. */
4129 if (mcnt
< 0 && (re_opcode_t
) *p1
== on_failure_jump
4130 && (re_opcode_t
) p1
[3] == start_memory
&& p1
[4] == *p
)
4132 /* If this group ever matched anything, then restore
4133 what its registers were before trying this last
4134 failed match, e.g., with `(a*)*b' against `ab' for
4135 regstart[1], and, e.g., with `((a*)*(b*)*)*'
4136 against `aba' for regend[3].
4138 Also restore the registers for inner groups for,
4139 e.g., `((a*)(b*))*' against `aba' (register 3 would
4140 otherwise get trashed). */
4142 if (EVER_MATCHED_SOMETHING (reg_info
[*p
]))
4146 EVER_MATCHED_SOMETHING (reg_info
[*p
]) = 0;
4148 /* Restore this and inner groups' (if any) registers. */
4149 for (r
= *p
; r
< *p
+ *(p
+ 1); r
++)
4151 regstart
[r
] = old_regstart
[r
];
4153 /* xx why this test? */
4154 if (old_regend
[r
] >= regstart
[r
])
4155 regend
[r
] = old_regend
[r
];
4159 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
4160 PUSH_FAILURE_POINT (p1
+ mcnt
, d
, -2);
4166 /* Move past the register number and the inner group count. */
4171 /* \<digit> has been turned into a `duplicate' command which is
4172 followed by the numeric value of <digit> as the register number. */
4175 register const char *d2
, *dend2
;
4176 int regno
= *p
++; /* Get which register to match against. */
4177 DEBUG_PRINT2 ("EXECUTING duplicate %d.\n", regno
);
4179 /* Can't back reference a group which we've never matched. */
4180 if (REG_UNSET (regstart
[regno
]) || REG_UNSET (regend
[regno
]))
4183 /* Where in input to try to start matching. */
4184 d2
= regstart
[regno
];
4186 /* Where to stop matching; if both the place to start and
4187 the place to stop matching are in the same string, then
4188 set to the place to stop, otherwise, for now have to use
4189 the end of the first string. */
4191 dend2
= ((FIRST_STRING_P (regstart
[regno
])
4192 == FIRST_STRING_P (regend
[regno
]))
4193 ? regend
[regno
] : end_match_1
);
4196 /* If necessary, advance to next segment in register
4200 if (dend2
== end_match_2
) break;
4201 if (dend2
== regend
[regno
]) break;
4203 /* End of string1 => advance to string2. */
4205 dend2
= regend
[regno
];
4207 /* At end of register contents => success */
4208 if (d2
== dend2
) break;
4210 /* If necessary, advance to next segment in data. */
4213 /* How many characters left in this segment to match. */
4216 /* Want how many consecutive characters we can match in
4217 one shot, so, if necessary, adjust the count. */
4218 if (mcnt
> dend2
- d2
)
4221 /* Compare that many; failure if mismatch, else move
4224 ? bcmp_translate (d
, d2
, mcnt
, translate
)
4225 : bcmp (d
, d2
, mcnt
))
4227 d
+= mcnt
, d2
+= mcnt
;
4229 /* Do this because we've match some characters. */
4230 SET_REGS_MATCHED ();
4236 /* begline matches the empty string at the beginning of the string
4237 (unless `not_bol' is set in `bufp'), and, if
4238 `newline_anchor' is set, after newlines. */
4240 DEBUG_PRINT1 ("EXECUTING begline.\n");
4242 if (AT_STRINGS_BEG (d
))
4244 if (!bufp
->not_bol
) break;
4246 else if (d
[-1] == '\n' && bufp
->newline_anchor
)
4250 /* In all other cases, we fail. */
4254 /* endline is the dual of begline. */
4256 DEBUG_PRINT1 ("EXECUTING endline.\n");
4258 if (AT_STRINGS_END (d
))
4260 if (!bufp
->not_eol
) break;
4263 /* We have to ``prefetch'' the next character. */
4264 else if ((d
== end1
? *string2
: *d
) == '\n'
4265 && bufp
->newline_anchor
)
4272 /* Match at the very beginning of the data. */
4274 DEBUG_PRINT1 ("EXECUTING begbuf.\n");
4275 if (AT_STRINGS_BEG (d
))
4280 /* Match at the very end of the data. */
4282 DEBUG_PRINT1 ("EXECUTING endbuf.\n");
4283 if (AT_STRINGS_END (d
))
4288 /* on_failure_keep_string_jump is used to optimize `.*\n'. It
4289 pushes NULL as the value for the string on the stack. Then
4290 `pop_failure_point' will keep the current value for the
4291 string, instead of restoring it. To see why, consider
4292 matching `foo\nbar' against `.*\n'. The .* matches the foo;
4293 then the . fails against the \n. But the next thing we want
4294 to do is match the \n against the \n; if we restored the
4295 string value, we would be back at the foo.
4297 Because this is used only in specific cases, we don't need to
4298 check all the things that `on_failure_jump' does, to make
4299 sure the right things get saved on the stack. Hence we don't
4300 share its code. The only reason to push anything on the
4301 stack at all is that otherwise we would have to change
4302 `anychar's code to do something besides goto fail in this
4303 case; that seems worse than this. */
4304 case on_failure_keep_string_jump
:
4305 DEBUG_PRINT1 ("EXECUTING on_failure_keep_string_jump");
4307 EXTRACT_NUMBER_AND_INCR (mcnt
, p
);
4308 DEBUG_PRINT3 (" %d (to 0x%x):\n", mcnt
, p
+ mcnt
);
4310 PUSH_FAILURE_POINT (p
+ mcnt
, NULL
, -2);
4314 /* Uses of on_failure_jump:
4316 Each alternative starts with an on_failure_jump that points
4317 to the beginning of the next alternative. Each alternative
4318 except the last ends with a jump that in effect jumps past
4319 the rest of the alternatives. (They really jump to the
4320 ending jump of the following alternative, because tensioning
4321 these jumps is a hassle.)
4323 Repeats start with an on_failure_jump that points past both
4324 the repetition text and either the following jump or
4325 pop_failure_jump back to this on_failure_jump. */
4326 case on_failure_jump
:
4328 DEBUG_PRINT1 ("EXECUTING on_failure_jump");
4330 EXTRACT_NUMBER_AND_INCR (mcnt
, p
);
4331 DEBUG_PRINT3 (" %d (to 0x%x)", mcnt
, p
+ mcnt
);
4333 /* If this on_failure_jump comes right before a group (i.e.,
4334 the original * applied to a group), save the information
4335 for that group and all inner ones, so that if we fail back
4336 to this point, the group's information will be correct.
4337 For example, in \(a*\)*\1, we need the preceding group,
4338 and in \(\(a*\)b*\)\2, we need the inner group. */
4340 /* We can't use `p' to check ahead because we push
4341 a failure point to `p + mcnt' after we do this. */
4344 /* We need to skip no_op's before we look for the
4345 start_memory in case this on_failure_jump is happening as
4346 the result of a completed succeed_n, as in \(a\)\{1,3\}b\1
4348 while (p1
< pend
&& (re_opcode_t
) *p1
== no_op
)
4351 if (p1
< pend
&& (re_opcode_t
) *p1
== start_memory
)
4353 /* We have a new highest active register now. This will
4354 get reset at the start_memory we are about to get to,
4355 but we will have saved all the registers relevant to
4356 this repetition op, as described above. */
4357 highest_active_reg
= *(p1
+ 1) + *(p1
+ 2);
4358 if (lowest_active_reg
== NO_LOWEST_ACTIVE_REG
)
4359 lowest_active_reg
= *(p1
+ 1);
4362 DEBUG_PRINT1 (":\n");
4363 PUSH_FAILURE_POINT (p
+ mcnt
, d
, -2);
4367 /* A smart repeat ends with `maybe_pop_jump'.
4368 We change it to either `pop_failure_jump' or `jump'. */
4369 case maybe_pop_jump
:
4370 EXTRACT_NUMBER_AND_INCR (mcnt
, p
);
4371 DEBUG_PRINT2 ("EXECUTING maybe_pop_jump %d.\n", mcnt
);
4373 register unsigned char *p2
= p
;
4375 /* Compare the beginning of the repeat with what in the
4376 pattern follows its end. If we can establish that there
4377 is nothing that they would both match, i.e., that we
4378 would have to backtrack because of (as in, e.g., `a*a')
4379 then we can change to pop_failure_jump, because we'll
4380 never have to backtrack.
4382 This is not true in the case of alternatives: in
4383 `(a|ab)*' we do need to backtrack to the `ab' alternative
4384 (e.g., if the string was `ab'). But instead of trying to
4385 detect that here, the alternative has put on a dummy
4386 failure point which is what we will end up popping. */
4388 /* Skip over open/close-group commands.
4389 If what follows this loop is a ...+ construct,
4390 look at what begins its body, since we will have to
4391 match at least one of that. */
4395 && ((re_opcode_t
) *p2
== stop_memory
4396 || (re_opcode_t
) *p2
== start_memory
))
4398 else if (p2
+ 6 < pend
4399 && (re_opcode_t
) *p2
== dummy_failure_jump
)
4406 /* p1[0] ... p1[2] are the `on_failure_jump' corresponding
4407 to the `maybe_finalize_jump' of this case. Examine what
4410 /* If we're at the end of the pattern, we can change. */
4413 /* Consider what happens when matching ":\(.*\)"
4414 against ":/". I don't really understand this code
4416 p
[-3] = (unsigned char) pop_failure_jump
;
4418 (" End of pattern: change to `pop_failure_jump'.\n");
4421 else if ((re_opcode_t
) *p2
== exactn
4422 || (bufp
->newline_anchor
&& (re_opcode_t
) *p2
== endline
))
4424 register unsigned char c
4425 = *p2
== (unsigned char) endline
? '\n' : p2
[2];
4427 if ((re_opcode_t
) p1
[3] == exactn
&& p1
[5] != c
)
4429 p
[-3] = (unsigned char) pop_failure_jump
;
4430 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n",
4434 else if ((re_opcode_t
) p1
[3] == charset
4435 || (re_opcode_t
) p1
[3] == charset_not
)
4437 int not = (re_opcode_t
) p1
[3] == charset_not
;
4439 if (c
< (unsigned char) (p1
[4] * BYTEWIDTH
)
4440 && p1
[5 + c
/ BYTEWIDTH
] & (1 << (c
% BYTEWIDTH
)))
4443 /* `not' is equal to 1 if c would match, which means
4444 that we can't change to pop_failure_jump. */
4447 p
[-3] = (unsigned char) pop_failure_jump
;
4448 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4452 else if ((re_opcode_t
) *p2
== charset
)
4455 register unsigned char c
4456 = *p2
== (unsigned char) endline
? '\n' : p2
[2];
4459 if ((re_opcode_t
) p1
[3] == exactn
4460 && ! ((int) p2
[1] * BYTEWIDTH
> (int) p1
[4]
4461 && (p2
[1 + p1
[4] / BYTEWIDTH
]
4462 & (1 << (p1
[4] % BYTEWIDTH
)))))
4464 p
[-3] = (unsigned char) pop_failure_jump
;
4465 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n",
4469 else if ((re_opcode_t
) p1
[3] == charset_not
)
4472 /* We win if the charset_not inside the loop
4473 lists every character listed in the charset after. */
4474 for (idx
= 0; idx
< (int) p2
[1]; idx
++)
4475 if (! (p2
[2 + idx
] == 0
4476 || (idx
< (int) p1
[4]
4477 && ((p2
[2 + idx
] & ~ p1
[5 + idx
]) == 0))))
4482 p
[-3] = (unsigned char) pop_failure_jump
;
4483 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4486 else if ((re_opcode_t
) p1
[3] == charset
)
4489 /* We win if the charset inside the loop
4490 has no overlap with the one after the loop. */
4492 idx
< (int) p2
[1] && idx
< (int) p1
[4];
4494 if ((p2
[2 + idx
] & p1
[5 + idx
]) != 0)
4497 if (idx
== p2
[1] || idx
== p1
[4])
4499 p
[-3] = (unsigned char) pop_failure_jump
;
4500 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4505 p
-= 2; /* Point at relative address again. */
4506 if ((re_opcode_t
) p
[-1] != pop_failure_jump
)
4508 p
[-1] = (unsigned char) jump
;
4509 DEBUG_PRINT1 (" Match => jump.\n");
4510 goto unconditional_jump
;
4512 /* Note fall through. */
4515 /* The end of a simple repeat has a pop_failure_jump back to
4516 its matching on_failure_jump, where the latter will push a
4517 failure point. The pop_failure_jump takes off failure
4518 points put on by this pop_failure_jump's matching
4519 on_failure_jump; we got through the pattern to here from the
4520 matching on_failure_jump, so didn't fail. */
4521 case pop_failure_jump
:
4523 /* We need to pass separate storage for the lowest and
4524 highest registers, even though we don't care about the
4525 actual values. Otherwise, we will restore only one
4526 register from the stack, since lowest will == highest in
4527 `pop_failure_point'. */
4528 unsigned dummy_low_reg
, dummy_high_reg
;
4529 unsigned char *pdummy
;
4532 DEBUG_PRINT1 ("EXECUTING pop_failure_jump.\n");
4533 POP_FAILURE_POINT (sdummy
, pdummy
,
4534 dummy_low_reg
, dummy_high_reg
,
4535 reg_dummy
, reg_dummy
, reg_info_dummy
);
4537 /* Note fall through. */
4540 /* Unconditionally jump (without popping any failure points). */
4543 EXTRACT_NUMBER_AND_INCR (mcnt
, p
); /* Get the amount to jump. */
4544 DEBUG_PRINT2 ("EXECUTING jump %d ", mcnt
);
4545 p
+= mcnt
; /* Do the jump. */
4546 DEBUG_PRINT2 ("(to 0x%x).\n", p
);
4550 /* We need this opcode so we can detect where alternatives end
4551 in `group_match_null_string_p' et al. */
4553 DEBUG_PRINT1 ("EXECUTING jump_past_alt.\n");
4554 goto unconditional_jump
;
4557 /* Normally, the on_failure_jump pushes a failure point, which
4558 then gets popped at pop_failure_jump. We will end up at
4559 pop_failure_jump, also, and with a pattern of, say, `a+', we
4560 are skipping over the on_failure_jump, so we have to push
4561 something meaningless for pop_failure_jump to pop. */
4562 case dummy_failure_jump
:
4563 DEBUG_PRINT1 ("EXECUTING dummy_failure_jump.\n");
4564 /* It doesn't matter what we push for the string here. What
4565 the code at `fail' tests is the value for the pattern. */
4566 PUSH_FAILURE_POINT (0, 0, -2);
4567 goto unconditional_jump
;
4570 /* At the end of an alternative, we need to push a dummy failure
4571 point in case we are followed by a `pop_failure_jump', because
4572 we don't want the failure point for the alternative to be
4573 popped. For example, matching `(a|ab)*' against `aab'
4574 requires that we match the `ab' alternative. */
4575 case push_dummy_failure
:
4576 DEBUG_PRINT1 ("EXECUTING push_dummy_failure.\n");
4577 /* See comments just above at `dummy_failure_jump' about the
4579 PUSH_FAILURE_POINT (0, 0, -2);
4582 /* Have to succeed matching what follows at least n times.
4583 After that, handle like `on_failure_jump'. */
4585 EXTRACT_NUMBER (mcnt
, p
+ 2);
4586 DEBUG_PRINT2 ("EXECUTING succeed_n %d.\n", mcnt
);
4589 /* Originally, this is how many times we HAVE to succeed. */
4594 STORE_NUMBER_AND_INCR (p
, mcnt
);
4595 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p
, mcnt
);
4599 DEBUG_PRINT2 (" Setting two bytes from 0x%x to no_op.\n", p
+2);
4600 p
[2] = (unsigned char) no_op
;
4601 p
[3] = (unsigned char) no_op
;
4607 EXTRACT_NUMBER (mcnt
, p
+ 2);
4608 DEBUG_PRINT2 ("EXECUTING jump_n %d.\n", mcnt
);
4610 /* Originally, this is how many times we CAN jump. */
4614 STORE_NUMBER (p
+ 2, mcnt
);
4615 goto unconditional_jump
;
4617 /* If don't have to jump any more, skip over the rest of command. */
4624 DEBUG_PRINT1 ("EXECUTING set_number_at.\n");
4626 EXTRACT_NUMBER_AND_INCR (mcnt
, p
);
4628 EXTRACT_NUMBER_AND_INCR (mcnt
, p
);
4629 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p1
, mcnt
);
4630 STORE_NUMBER (p1
, mcnt
);
4635 DEBUG_PRINT1 ("EXECUTING wordbound.\n");
4636 if (AT_WORD_BOUNDARY (d
))
4641 DEBUG_PRINT1 ("EXECUTING notwordbound.\n");
4642 if (AT_WORD_BOUNDARY (d
))
4647 DEBUG_PRINT1 ("EXECUTING wordbeg.\n");
4648 if (WORDCHAR_P (d
) && (AT_STRINGS_BEG (d
) || !WORDCHAR_P (d
- 1)))
4653 DEBUG_PRINT1 ("EXECUTING wordend.\n");
4654 if (!AT_STRINGS_BEG (d
) && WORDCHAR_P (d
- 1)
4655 && (!WORDCHAR_P (d
) || AT_STRINGS_END (d
)))
4661 DEBUG_PRINT1 ("EXECUTING before_dot.\n");
4662 if (PTR_CHAR_POS ((unsigned char *) d
) >= point
)
4667 DEBUG_PRINT1 ("EXECUTING at_dot.\n");
4668 if (PTR_CHAR_POS ((unsigned char *) d
) != point
)
4673 DEBUG_PRINT1 ("EXECUTING after_dot.\n");
4674 if (PTR_CHAR_POS ((unsigned char *) d
) <= point
)
4677 #if 0 /* not emacs19 */
4679 DEBUG_PRINT1 ("EXECUTING at_dot.\n");
4680 if (PTR_CHAR_POS ((unsigned char *) d
) + 1 != point
)
4683 #endif /* not emacs19 */
4686 DEBUG_PRINT2 ("EXECUTING syntaxspec %d.\n", mcnt
);
4691 DEBUG_PRINT1 ("EXECUTING Emacs wordchar.\n");
4695 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
4697 if (SYNTAX (d
[-1]) != (enum syntaxcode
) mcnt
)
4699 SET_REGS_MATCHED ();
4703 DEBUG_PRINT2 ("EXECUTING notsyntaxspec %d.\n", mcnt
);
4705 goto matchnotsyntax
;
4708 DEBUG_PRINT1 ("EXECUTING Emacs notwordchar.\n");
4712 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
4714 if (SYNTAX (d
[-1]) == (enum syntaxcode
) mcnt
)
4716 SET_REGS_MATCHED ();
4719 #else /* not emacs */
4721 DEBUG_PRINT1 ("EXECUTING non-Emacs wordchar.\n");
4723 if (!WORDCHAR_P (d
))
4725 SET_REGS_MATCHED ();
4730 DEBUG_PRINT1 ("EXECUTING non-Emacs notwordchar.\n");
4734 SET_REGS_MATCHED ();
4737 #endif /* not emacs */
4742 continue; /* Successfully executed one pattern command; keep going. */
4745 /* We goto here if a matching operation fails. */
4747 if (!FAIL_STACK_EMPTY ())
4748 { /* A restart point is known. Restore to that state. */
4749 DEBUG_PRINT1 ("\nFAIL:\n");
4750 POP_FAILURE_POINT (d
, p
,
4751 lowest_active_reg
, highest_active_reg
,
4752 regstart
, regend
, reg_info
);
4754 /* If this failure point is a dummy, try the next one. */
4758 /* If we failed to the end of the pattern, don't examine *p. */
4762 boolean is_a_jump_n
= false;
4764 /* If failed to a backwards jump that's part of a repetition
4765 loop, need to pop this failure point and use the next one. */
4766 switch ((re_opcode_t
) *p
)
4770 case maybe_pop_jump
:
4771 case pop_failure_jump
:
4774 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
4777 if ((is_a_jump_n
&& (re_opcode_t
) *p1
== succeed_n
)
4779 && (re_opcode_t
) *p1
== on_failure_jump
))
4787 if (d
>= string1
&& d
<= end1
)
4791 break; /* Matching at this starting point really fails. */
4795 goto restore_best_regs
;
4799 return -1; /* Failure to match. */
4802 /* Subroutine definitions for re_match_2. */
4805 /* We are passed P pointing to a register number after a start_memory.
4807 Return true if the pattern up to the corresponding stop_memory can
4808 match the empty string, and false otherwise.
4810 If we find the matching stop_memory, sets P to point to one past its number.
4811 Otherwise, sets P to an undefined byte less than or equal to END.
4813 We don't handle duplicates properly (yet). */
4816 group_match_null_string_p (p
, end
, reg_info
)
4817 unsigned char **p
, *end
;
4818 register_info_type
*reg_info
;
4821 /* Point to after the args to the start_memory. */
4822 unsigned char *p1
= *p
+ 2;
4826 /* Skip over opcodes that can match nothing, and return true or
4827 false, as appropriate, when we get to one that can't, or to the
4828 matching stop_memory. */
4830 switch ((re_opcode_t
) *p1
)
4832 /* Could be either a loop or a series of alternatives. */
4833 case on_failure_jump
:
4835 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
4837 /* If the next operation is not a jump backwards in the
4842 /* Go through the on_failure_jumps of the alternatives,
4843 seeing if any of the alternatives cannot match nothing.
4844 The last alternative starts with only a jump,
4845 whereas the rest start with on_failure_jump and end
4846 with a jump, e.g., here is the pattern for `a|b|c':
4848 /on_failure_jump/0/6/exactn/1/a/jump_past_alt/0/6
4849 /on_failure_jump/0/6/exactn/1/b/jump_past_alt/0/3
4852 So, we have to first go through the first (n-1)
4853 alternatives and then deal with the last one separately. */
4856 /* Deal with the first (n-1) alternatives, which start
4857 with an on_failure_jump (see above) that jumps to right
4858 past a jump_past_alt. */
4860 while ((re_opcode_t
) p1
[mcnt
-3] == jump_past_alt
)
4862 /* `mcnt' holds how many bytes long the alternative
4863 is, including the ending `jump_past_alt' and
4866 if (!alt_match_null_string_p (p1
, p1
+ mcnt
- 3,
4870 /* Move to right after this alternative, including the
4874 /* Break if it's the beginning of an n-th alternative
4875 that doesn't begin with an on_failure_jump. */
4876 if ((re_opcode_t
) *p1
!= on_failure_jump
)
4879 /* Still have to check that it's not an n-th
4880 alternative that starts with an on_failure_jump. */
4882 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
4883 if ((re_opcode_t
) p1
[mcnt
-3] != jump_past_alt
)
4885 /* Get to the beginning of the n-th alternative. */
4891 /* Deal with the last alternative: go back and get number
4892 of the `jump_past_alt' just before it. `mcnt' contains
4893 the length of the alternative. */
4894 EXTRACT_NUMBER (mcnt
, p1
- 2);
4896 if (!alt_match_null_string_p (p1
, p1
+ mcnt
, reg_info
))
4899 p1
+= mcnt
; /* Get past the n-th alternative. */
4905 assert (p1
[1] == **p
);
4911 if (!common_op_match_null_string_p (&p1
, end
, reg_info
))
4914 } /* while p1 < end */
4917 } /* group_match_null_string_p */
4920 /* Similar to group_match_null_string_p, but doesn't deal with alternatives:
4921 It expects P to be the first byte of a single alternative and END one
4922 byte past the last. The alternative can contain groups. */
4925 alt_match_null_string_p (p
, end
, reg_info
)
4926 unsigned char *p
, *end
;
4927 register_info_type
*reg_info
;
4930 unsigned char *p1
= p
;
4934 /* Skip over opcodes that can match nothing, and break when we get
4935 to one that can't. */
4937 switch ((re_opcode_t
) *p1
)
4940 case on_failure_jump
:
4942 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
4947 if (!common_op_match_null_string_p (&p1
, end
, reg_info
))
4950 } /* while p1 < end */
4953 } /* alt_match_null_string_p */
4956 /* Deals with the ops common to group_match_null_string_p and
4957 alt_match_null_string_p.
4959 Sets P to one after the op and its arguments, if any. */
4962 common_op_match_null_string_p (p
, end
, reg_info
)
4963 unsigned char **p
, *end
;
4964 register_info_type
*reg_info
;
4969 unsigned char *p1
= *p
;
4971 switch ((re_opcode_t
) *p1
++)
4991 assert (reg_no
> 0 && reg_no
<= MAX_REGNUM
);
4992 ret
= group_match_null_string_p (&p1
, end
, reg_info
);
4994 /* Have to set this here in case we're checking a group which
4995 contains a group and a back reference to it. */
4997 if (REG_MATCH_NULL_STRING_P (reg_info
[reg_no
]) == MATCH_NULL_UNSET_VALUE
)
4998 REG_MATCH_NULL_STRING_P (reg_info
[reg_no
]) = ret
;
5004 /* If this is an optimized succeed_n for zero times, make the jump. */
5006 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
5014 /* Get to the number of times to succeed. */
5016 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
5021 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
5029 if (!REG_MATCH_NULL_STRING_P (reg_info
[*p1
]))
5037 /* All other opcodes mean we cannot match the empty string. */
5043 } /* common_op_match_null_string_p */
5046 /* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
5047 bytes; nonzero otherwise. */
5050 bcmp_translate (s1
, s2
, len
, translate
)
5051 unsigned char *s1
, *s2
;
5055 register unsigned char *p1
= s1
, *p2
= s2
;
5058 if (translate
[*p1
++] != translate
[*p2
++]) return 1;
5064 /* Entry points for GNU code. */
5066 /* re_compile_pattern is the GNU regular expression compiler: it
5067 compiles PATTERN (of length SIZE) and puts the result in BUFP.
5068 Returns 0 if the pattern was valid, otherwise an error string.
5070 Assumes the `allocated' (and perhaps `buffer') and `translate' fields
5071 are set in BUFP on entry.
5073 We call regex_compile to do the actual compilation. */
5076 re_compile_pattern (pattern
, length
, bufp
)
5077 const char *pattern
;
5079 struct re_pattern_buffer
*bufp
;
5083 /* GNU code is written to assume at least RE_NREGS registers will be set
5084 (and at least one extra will be -1). */
5085 bufp
->regs_allocated
= REGS_UNALLOCATED
;
5087 /* And GNU code determines whether or not to get register information
5088 by passing null for the REGS argument to re_match, etc., not by
5092 /* Match anchors at newline. */
5093 bufp
->newline_anchor
= 1;
5095 ret
= regex_compile (pattern
, length
, re_syntax_options
, bufp
);
5099 return gettext (re_error_msgid
[(int) ret
]);
5102 /* Entry points compatible with 4.2 BSD regex library. We don't define
5103 them unless specifically requested. */
5105 #ifdef _REGEX_RE_COMP
5107 /* BSD has one and only one pattern buffer. */
5108 static struct re_pattern_buffer re_comp_buf
;
5118 if (!re_comp_buf
.buffer
)
5119 return gettext ("No previous regular expression");
5123 if (!re_comp_buf
.buffer
)
5125 re_comp_buf
.buffer
= (unsigned char *) malloc (200);
5126 if (re_comp_buf
.buffer
== NULL
)
5127 return gettext (re_error_msgid
[(int) REG_ESPACE
]);
5128 re_comp_buf
.allocated
= 200;
5130 re_comp_buf
.fastmap
= (char *) malloc (1 << BYTEWIDTH
);
5131 if (re_comp_buf
.fastmap
== NULL
)
5132 return gettext (re_error_msgid
[(int) REG_ESPACE
]);
5135 /* Since `re_exec' always passes NULL for the `regs' argument, we
5136 don't need to initialize the pattern buffer fields which affect it. */
5138 /* Match anchors at newlines. */
5139 re_comp_buf
.newline_anchor
= 1;
5141 ret
= regex_compile (s
, strlen (s
), re_syntax_options
, &re_comp_buf
);
5146 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
5147 return (char *) gettext (re_error_msgid
[(int) ret
]);
5155 const int len
= strlen (s
);
5157 0 <= re_search (&re_comp_buf
, s
, len
, 0, len
, (struct re_registers
*) 0);
5159 #endif /* _REGEX_RE_COMP */
5161 /* POSIX.2 functions. Don't define these for Emacs. */
5165 /* regcomp takes a regular expression as a string and compiles it.
5167 PREG is a regex_t *. We do not expect any fields to be initialized,
5168 since POSIX says we shouldn't. Thus, we set
5170 `buffer' to the compiled pattern;
5171 `used' to the length of the compiled pattern;
5172 `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
5173 REG_EXTENDED bit in CFLAGS is set; otherwise, to
5174 RE_SYNTAX_POSIX_BASIC;
5175 `newline_anchor' to REG_NEWLINE being set in CFLAGS;
5176 `fastmap' and `fastmap_accurate' to zero;
5177 `re_nsub' to the number of subexpressions in PATTERN.
5179 PATTERN is the address of the pattern string.
5181 CFLAGS is a series of bits which affect compilation.
5183 If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
5184 use POSIX basic syntax.
5186 If REG_NEWLINE is set, then . and [^...] don't match newline.
5187 Also, regexec will try a match beginning after every newline.
5189 If REG_ICASE is set, then we considers upper- and lowercase
5190 versions of letters to be equivalent when matching.
5192 If REG_NOSUB is set, then when PREG is passed to regexec, that
5193 routine will report only success or failure, and nothing about the
5196 It returns 0 if it succeeds, nonzero if it doesn't. (See regex.h for
5197 the return codes and their meanings.) */
5200 regcomp (preg
, pattern
, cflags
)
5202 const char *pattern
;
5207 = (cflags
& REG_EXTENDED
) ?
5208 RE_SYNTAX_POSIX_EXTENDED
: RE_SYNTAX_POSIX_BASIC
;
5210 /* regex_compile will allocate the space for the compiled pattern. */
5212 preg
->allocated
= 0;
5215 /* Don't bother to use a fastmap when searching. This simplifies the
5216 REG_NEWLINE case: if we used a fastmap, we'd have to put all the
5217 characters after newlines into the fastmap. This way, we just try
5221 if (cflags
& REG_ICASE
)
5225 preg
->translate
= (char *) malloc (CHAR_SET_SIZE
);
5226 if (preg
->translate
== NULL
)
5227 return (int) REG_ESPACE
;
5229 /* Map uppercase characters to corresponding lowercase ones. */
5230 for (i
= 0; i
< CHAR_SET_SIZE
; i
++)
5231 preg
->translate
[i
] = ISUPPER (i
) ? tolower (i
) : i
;
5234 preg
->translate
= NULL
;
5236 /* If REG_NEWLINE is set, newlines are treated differently. */
5237 if (cflags
& REG_NEWLINE
)
5238 { /* REG_NEWLINE implies neither . nor [^...] match newline. */
5239 syntax
&= ~RE_DOT_NEWLINE
;
5240 syntax
|= RE_HAT_LISTS_NOT_NEWLINE
;
5241 /* It also changes the matching behavior. */
5242 preg
->newline_anchor
= 1;
5245 preg
->newline_anchor
= 0;
5247 preg
->no_sub
= !!(cflags
& REG_NOSUB
);
5249 /* POSIX says a null character in the pattern terminates it, so we
5250 can use strlen here in compiling the pattern. */
5251 ret
= regex_compile (pattern
, strlen (pattern
), syntax
, preg
);
5253 /* POSIX doesn't distinguish between an unmatched open-group and an
5254 unmatched close-group: both are REG_EPAREN. */
5255 if (ret
== REG_ERPAREN
) ret
= REG_EPAREN
;
5261 /* regexec searches for a given pattern, specified by PREG, in the
5264 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
5265 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
5266 least NMATCH elements, and we set them to the offsets of the
5267 corresponding matched substrings.
5269 EFLAGS specifies `execution flags' which affect matching: if
5270 REG_NOTBOL is set, then ^ does not match at the beginning of the
5271 string; if REG_NOTEOL is set, then $ does not match at the end.
5273 We return 0 if we find a match and REG_NOMATCH if not. */
5276 regexec (preg
, string
, nmatch
, pmatch
, eflags
)
5277 const regex_t
*preg
;
5280 regmatch_t pmatch
[];
5284 struct re_registers regs
;
5285 regex_t private_preg
;
5286 int len
= strlen (string
);
5287 boolean want_reg_info
= !preg
->no_sub
&& nmatch
> 0;
5289 private_preg
= *preg
;
5291 private_preg
.not_bol
= !!(eflags
& REG_NOTBOL
);
5292 private_preg
.not_eol
= !!(eflags
& REG_NOTEOL
);
5294 /* The user has told us exactly how many registers to return
5295 information about, via `nmatch'. We have to pass that on to the
5296 matching routines. */
5297 private_preg
.regs_allocated
= REGS_FIXED
;
5301 regs
.num_regs
= nmatch
;
5302 regs
.start
= TALLOC (nmatch
, regoff_t
);
5303 regs
.end
= TALLOC (nmatch
, regoff_t
);
5304 if (regs
.start
== NULL
|| regs
.end
== NULL
)
5305 return (int) REG_NOMATCH
;
5308 /* Perform the searching operation. */
5309 ret
= re_search (&private_preg
, string
, len
,
5310 /* start: */ 0, /* range: */ len
,
5311 want_reg_info
? ®s
: (struct re_registers
*) 0);
5313 /* Copy the register information to the POSIX structure. */
5320 for (r
= 0; r
< nmatch
; r
++)
5322 pmatch
[r
].rm_so
= regs
.start
[r
];
5323 pmatch
[r
].rm_eo
= regs
.end
[r
];
5327 /* If we needed the temporary register info, free the space now. */
5332 /* We want zero return to mean success, unlike `re_search'. */
5333 return ret
>= 0 ? (int) REG_NOERROR
: (int) REG_NOMATCH
;
5337 /* Returns a message corresponding to an error code, ERRCODE, returned
5338 from either regcomp or regexec. We don't use PREG here. */
5341 regerror (errcode
, preg
, errbuf
, errbuf_size
)
5343 const regex_t
*preg
;
5351 || errcode
>= (sizeof (re_error_msgid
) / sizeof (re_error_msgid
[0])))
5352 /* Only error codes returned by the rest of the code should be passed
5353 to this routine. If we are given anything else, or if other regex
5354 code generates an invalid error code, then the program has a bug.
5355 Dump core so we can fix it. */
5358 msg
= gettext (re_error_msgid
[errcode
]);
5360 msg_size
= strlen (msg
) + 1; /* Includes the null. */
5362 if (errbuf_size
!= 0)
5364 if (msg_size
> errbuf_size
)
5366 strncpy (errbuf
, msg
, errbuf_size
- 1);
5367 errbuf
[errbuf_size
- 1] = 0;
5370 strcpy (errbuf
, msg
);
5377 /* Free dynamically allocated space used by PREG. */
5383 if (preg
->buffer
!= NULL
)
5384 free (preg
->buffer
);
5385 preg
->buffer
= NULL
;
5387 preg
->allocated
= 0;
5390 if (preg
->fastmap
!= NULL
)
5391 free (preg
->fastmap
);
5392 preg
->fastmap
= NULL
;
5393 preg
->fastmap_accurate
= 0;
5395 if (preg
->translate
!= NULL
)
5396 free (preg
->translate
);
5397 preg
->translate
= NULL
;
5400 #endif /* not emacs */
5404 make-backup-files: t
5406 trim-versions-without-asking: nil