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 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)
30 #if defined (emacs) || defined (CONFIG_BROKETS)
31 /* We use <config.h> instead of "config.h" so that a compilation
32 using -I. -I$srcdir will use ./config.h rather than $srcdir/config.h
33 (which it would do because it found this file in $srcdir). */
40 /* We need this for `regex.h', and perhaps for the Emacs include files. */
41 #include <sys/types.h>
43 /* The `emacs' switch turns on certain matching commands
44 that make sense only in Emacs. */
51 /* Emacs uses `NULL' as a predicate. */
64 /* We used to test for `BSTRING' here, but only GCC and Emacs define
65 `BSTRING', as far as I know, and neither of them use this code. */
66 #ifndef INHIBIT_STRING_HEADER
67 #if HAVE_STRING_H || STDC_HEADERS
70 #define bcmp(s1, s2, n) memcmp ((s1), (s2), (n))
73 #define bcopy(s, d, n) memcpy ((d), (s), (n))
76 #define bzero(s, n) memset ((s), 0, (n))
83 /* Define the syntax stuff for \<, \>, etc. */
85 /* This must be nonzero for the wordchar and notwordchar pattern
86 commands in re_match_2. */
93 extern char *re_syntax_table
;
95 #else /* not SYNTAX_TABLE */
97 /* How many characters in the character set. */
98 #define CHAR_SET_SIZE 256
100 static char re_syntax_table
[CHAR_SET_SIZE
];
111 bzero (re_syntax_table
, sizeof re_syntax_table
);
113 for (c
= 'a'; c
<= 'z'; c
++)
114 re_syntax_table
[c
] = Sword
;
116 for (c
= 'A'; c
<= 'Z'; c
++)
117 re_syntax_table
[c
] = Sword
;
119 for (c
= '0'; c
<= '9'; c
++)
120 re_syntax_table
[c
] = Sword
;
122 re_syntax_table
['_'] = Sword
;
127 #endif /* not SYNTAX_TABLE */
129 #define SYNTAX(c) re_syntax_table[c]
131 #endif /* not emacs */
133 /* Get the interface, including the syntax bits. */
136 /* isalpha etc. are used for the character classes. */
139 /* Jim Meyering writes:
141 "... Some ctype macros are valid only for character codes that
142 isascii says are ASCII (SGI's IRIX-4.0.5 is one such system --when
143 using /bin/cc or gcc but without giving an ansi option). So, all
144 ctype uses should be through macros like ISPRINT... If
145 STDC_HEADERS is defined, then autoconf has verified that the ctype
146 macros don't need to be guarded with references to isascii. ...
147 Defining isascii to 1 should let any compiler worth its salt
148 eliminate the && through constant folding." */
150 #if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII))
153 #define ISASCII(c) isascii(c)
157 #define ISBLANK(c) (ISASCII (c) && isblank (c))
159 #define ISBLANK(c) ((c) == ' ' || (c) == '\t')
162 #define ISGRAPH(c) (ISASCII (c) && isgraph (c))
164 #define ISGRAPH(c) (ISASCII (c) && isprint (c) && !isspace (c))
167 #define ISPRINT(c) (ISASCII (c) && isprint (c))
168 #define ISDIGIT(c) (ISASCII (c) && isdigit (c))
169 #define ISALNUM(c) (ISASCII (c) && isalnum (c))
170 #define ISALPHA(c) (ISASCII (c) && isalpha (c))
171 #define ISCNTRL(c) (ISASCII (c) && iscntrl (c))
172 #define ISLOWER(c) (ISASCII (c) && islower (c))
173 #define ISPUNCT(c) (ISASCII (c) && ispunct (c))
174 #define ISSPACE(c) (ISASCII (c) && isspace (c))
175 #define ISUPPER(c) (ISASCII (c) && isupper (c))
176 #define ISXDIGIT(c) (ISASCII (c) && isxdigit (c))
182 /* We remove any previous definition of `SIGN_EXTEND_CHAR',
183 since ours (we hope) works properly with all combinations of
184 machines, compilers, `char' and `unsigned char' argument types.
185 (Per Bothner suggested the basic approach.) */
186 #undef SIGN_EXTEND_CHAR
188 #define SIGN_EXTEND_CHAR(c) ((signed char) (c))
189 #else /* not __STDC__ */
190 /* As in Harbison and Steele. */
191 #define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128)
194 /* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we
195 use `alloca' instead of `malloc'. This is because using malloc in
196 re_search* or re_match* could cause memory leaks when C-g is used in
197 Emacs; also, malloc is slower and causes storage fragmentation. On
198 the other hand, malloc is more portable, and easier to debug.
200 Because we sometimes use alloca, some routines have to be macros,
201 not functions -- `alloca'-allocated space disappears at the end of the
202 function it is called in. */
206 #define REGEX_ALLOCATE malloc
207 #define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
209 #else /* not REGEX_MALLOC */
211 /* Emacs already defines alloca, sometimes. */
214 /* Make alloca work the best possible way. */
216 #define alloca __builtin_alloca
217 #else /* not __GNUC__ */
220 #else /* not __GNUC__ or HAVE_ALLOCA_H */
221 #ifndef _AIX /* Already did AIX, up at the top. */
223 #endif /* not _AIX */
224 #endif /* not HAVE_ALLOCA_H */
225 #endif /* not __GNUC__ */
227 #endif /* not alloca */
229 #define REGEX_ALLOCATE alloca
231 /* Assumes a `char *destination' variable. */
232 #define REGEX_REALLOCATE(source, osize, nsize) \
233 (destination = (char *) alloca (nsize), \
234 bcopy (source, destination, osize), \
237 #endif /* not REGEX_MALLOC */
240 /* True if `size1' is non-NULL and PTR is pointing anywhere inside
241 `string1' or just past its end. This works if PTR is NULL, which is
243 #define FIRST_STRING_P(ptr) \
244 (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
246 /* (Re)Allocate N items of type T using malloc, or fail. */
247 #define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
248 #define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
249 #define RETALLOC_IF(addr, n, t) \
250 if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
251 #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
253 #define BYTEWIDTH 8 /* In bits. */
255 #define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
259 #define MAX(a, b) ((a) > (b) ? (a) : (b))
260 #define MIN(a, b) ((a) < (b) ? (a) : (b))
262 typedef char boolean
;
266 static int re_match_2_internal ();
268 /* These are the command codes that appear in compiled regular
269 expressions. Some opcodes are followed by argument bytes. A
270 command code can specify any interpretation whatsoever for its
271 arguments. Zero bytes may appear in the compiled regular expression.
273 The value of `exactn' is needed in search.c (search_buffer) in Emacs.
274 So regex.h defines a symbol `RE_EXACTN_VALUE' to be 1; the value of
275 `exactn' we use here must also be 1. */
281 /* Followed by one byte giving n, then by n literal bytes. */
284 /* Matches any (more or less) character. */
287 /* Matches any one char belonging to specified set. First
288 following byte is number of bitmap bytes. Then come bytes
289 for a bitmap saying which chars are in. Bits in each byte
290 are ordered low-bit-first. A character is in the set if its
291 bit is 1. A character too large to have a bit in the map is
292 automatically not in the set. */
295 /* Same parameters as charset, but match any character that is
296 not one of those specified. */
299 /* Start remembering the text that is matched, for storing in a
300 register. Followed by one byte with the register number, in
301 the range 0 to one less than the pattern buffer's re_nsub
302 field. Then followed by one byte with the number of groups
303 inner to this one. (This last has to be part of the
304 start_memory only because we need it in the on_failure_jump
308 /* Stop remembering the text that is matched and store it in a
309 memory register. Followed by one byte with the register
310 number, in the range 0 to one less than `re_nsub' in the
311 pattern buffer, and one byte with the number of inner groups,
312 just like `start_memory'. (We need the number of inner
313 groups here because we don't have any easy way of finding the
314 corresponding start_memory when we're at a stop_memory.) */
317 /* Match a duplicate of something remembered. Followed by one
318 byte containing the register number. */
321 /* Fail unless at beginning of line. */
324 /* Fail unless at end of line. */
327 /* Succeeds if at beginning of buffer (if emacs) or at beginning
328 of string to be matched (if not). */
331 /* Analogously, for end of buffer/string. */
334 /* Followed by two byte relative address to which to jump. */
337 /* Same as jump, but marks the end of an alternative. */
340 /* Followed by two-byte relative address of place to resume at
341 in case of failure. */
344 /* Like on_failure_jump, but pushes a placeholder instead of the
345 current string position when executed. */
346 on_failure_keep_string_jump
,
348 /* Throw away latest failure point and then jump to following
349 two-byte relative address. */
352 /* Change to pop_failure_jump if know won't have to backtrack to
353 match; otherwise change to jump. This is used to jump
354 back to the beginning of a repeat. If what follows this jump
355 clearly won't match what the repeat does, such that we can be
356 sure that there is no use backtracking out of repetitions
357 already matched, then we change it to a pop_failure_jump.
358 Followed by two-byte address. */
361 /* Jump to following two-byte address, and push a dummy failure
362 point. This failure point will be thrown away if an attempt
363 is made to use it for a failure. A `+' construct makes this
364 before the first repeat. Also used as an intermediary kind
365 of jump when compiling an alternative. */
368 /* Push a dummy failure point and continue. Used at the end of
372 /* Followed by two-byte relative address and two-byte number n.
373 After matching N times, jump to the address upon failure. */
376 /* Followed by two-byte relative address, and two-byte number n.
377 Jump to the address N times, then fail. */
380 /* Set the following two-byte relative address to the
381 subsequent two-byte number. The address *includes* the two
385 wordchar
, /* Matches any word-constituent character. */
386 notwordchar
, /* Matches any char that is not a word-constituent. */
388 wordbeg
, /* Succeeds if at word beginning. */
389 wordend
, /* Succeeds if at word end. */
391 wordbound
, /* Succeeds if at a word boundary. */
392 notwordbound
/* Succeeds if not at a word boundary. */
395 ,before_dot
, /* Succeeds if before point. */
396 at_dot
, /* Succeeds if at point. */
397 after_dot
, /* Succeeds if after point. */
399 /* Matches any character whose syntax is specified. Followed by
400 a byte which contains a syntax code, e.g., Sword. */
403 /* Matches any character whose syntax is not that specified. */
408 /* Common operations on the compiled pattern. */
410 /* Store NUMBER in two contiguous bytes starting at DESTINATION. */
412 #define STORE_NUMBER(destination, number) \
414 (destination)[0] = (number) & 0377; \
415 (destination)[1] = (number) >> 8; \
418 /* Same as STORE_NUMBER, except increment DESTINATION to
419 the byte after where the number is stored. Therefore, DESTINATION
420 must be an lvalue. */
422 #define STORE_NUMBER_AND_INCR(destination, number) \
424 STORE_NUMBER (destination, number); \
425 (destination) += 2; \
428 /* Put into DESTINATION a number stored in two contiguous bytes starting
431 #define EXTRACT_NUMBER(destination, source) \
433 (destination) = *(source) & 0377; \
434 (destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8; \
439 extract_number (dest
, source
)
441 unsigned char *source
;
443 int temp
= SIGN_EXTEND_CHAR (*(source
+ 1));
444 *dest
= *source
& 0377;
448 #ifndef EXTRACT_MACROS /* To debug the macros. */
449 #undef EXTRACT_NUMBER
450 #define EXTRACT_NUMBER(dest, src) extract_number (&dest, src)
451 #endif /* not EXTRACT_MACROS */
455 /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
456 SOURCE must be an lvalue. */
458 #define EXTRACT_NUMBER_AND_INCR(destination, source) \
460 EXTRACT_NUMBER (destination, source); \
466 extract_number_and_incr (destination
, source
)
468 unsigned char **source
;
470 extract_number (destination
, *source
);
474 #ifndef EXTRACT_MACROS
475 #undef EXTRACT_NUMBER_AND_INCR
476 #define EXTRACT_NUMBER_AND_INCR(dest, src) \
477 extract_number_and_incr (&dest, &src)
478 #endif /* not EXTRACT_MACROS */
482 /* If DEBUG is defined, Regex prints many voluminous messages about what
483 it is doing (if the variable `debug' is nonzero). If linked with the
484 main program in `iregex.c', you can enter patterns and strings
485 interactively. And if linked with the main program in `main.c' and
486 the other test files, you can run the already-written tests. */
490 /* We use standard I/O for debugging. */
493 /* It is useful to test things that ``must'' be true when debugging. */
496 static int debug
= 0;
498 #define DEBUG_STATEMENT(e) e
499 #define DEBUG_PRINT1(x) if (debug) printf (x)
500 #define DEBUG_PRINT2(x1, x2) if (debug) printf (x1, x2)
501 #define DEBUG_PRINT3(x1, x2, x3) if (debug) printf (x1, x2, x3)
502 #define DEBUG_PRINT4(x1, x2, x3, x4) if (debug) printf (x1, x2, x3, x4)
503 #define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) \
504 if (debug) print_partial_compiled_pattern (s, e)
505 #define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) \
506 if (debug) print_double_string (w, s1, sz1, s2, sz2)
509 extern void printchar ();
511 /* Print the fastmap in human-readable form. */
514 print_fastmap (fastmap
)
517 unsigned was_a_range
= 0;
520 while (i
< (1 << BYTEWIDTH
))
526 while (i
< (1 << BYTEWIDTH
) && fastmap
[i
])
542 /* Print a compiled pattern string in human-readable form, starting at
543 the START pointer into it and ending just before the pointer END. */
546 print_partial_compiled_pattern (start
, end
)
547 unsigned char *start
;
551 unsigned char *p
= start
;
552 unsigned char *pend
= end
;
560 /* Loop over pattern commands. */
563 printf ("%d:\t", p
- start
);
565 switch ((re_opcode_t
) *p
++)
573 printf ("/exactn/%d", mcnt
);
584 printf ("/start_memory/%d/%d", mcnt
, *p
++);
589 printf ("/stop_memory/%d/%d", mcnt
, *p
++);
593 printf ("/duplicate/%d", *p
++);
603 register int c
, last
= -100;
604 register int in_range
= 0;
606 printf ("/charset [%s",
607 (re_opcode_t
) *(p
- 1) == charset_not
? "^" : "");
609 assert (p
+ *p
< pend
);
611 for (c
= 0; c
< 256; c
++)
613 && (p
[1 + (c
/8)] & (1 << (c
% 8))))
615 /* Are we starting a range? */
616 if (last
+ 1 == c
&& ! in_range
)
621 /* Have we broken a range? */
622 else if (last
+ 1 != c
&& in_range
)
651 case on_failure_jump
:
652 extract_number_and_incr (&mcnt
, &p
);
653 printf ("/on_failure_jump to %d", p
+ mcnt
- start
);
656 case on_failure_keep_string_jump
:
657 extract_number_and_incr (&mcnt
, &p
);
658 printf ("/on_failure_keep_string_jump to %d", p
+ mcnt
- start
);
661 case dummy_failure_jump
:
662 extract_number_and_incr (&mcnt
, &p
);
663 printf ("/dummy_failure_jump to %d", p
+ mcnt
- start
);
666 case push_dummy_failure
:
667 printf ("/push_dummy_failure");
671 extract_number_and_incr (&mcnt
, &p
);
672 printf ("/maybe_pop_jump to %d", p
+ mcnt
- start
);
675 case pop_failure_jump
:
676 extract_number_and_incr (&mcnt
, &p
);
677 printf ("/pop_failure_jump to %d", p
+ mcnt
- start
);
681 extract_number_and_incr (&mcnt
, &p
);
682 printf ("/jump_past_alt to %d", p
+ mcnt
- start
);
686 extract_number_and_incr (&mcnt
, &p
);
687 printf ("/jump to %d", p
+ mcnt
- start
);
691 extract_number_and_incr (&mcnt
, &p
);
692 extract_number_and_incr (&mcnt2
, &p
);
693 printf ("/succeed_n to %d, %d times", p
+ mcnt
- start
, mcnt2
);
697 extract_number_and_incr (&mcnt
, &p
);
698 extract_number_and_incr (&mcnt2
, &p
);
699 printf ("/jump_n to %d, %d times", p
+ mcnt
- start
, mcnt2
);
703 extract_number_and_incr (&mcnt
, &p
);
704 extract_number_and_incr (&mcnt2
, &p
);
705 printf ("/set_number_at location %d to %d", p
+ mcnt
- start
, mcnt2
);
709 printf ("/wordbound");
713 printf ("/notwordbound");
725 printf ("/before_dot");
733 printf ("/after_dot");
737 printf ("/syntaxspec");
739 printf ("/%d", mcnt
);
743 printf ("/notsyntaxspec");
745 printf ("/%d", mcnt
);
750 printf ("/wordchar");
754 printf ("/notwordchar");
766 printf ("?%d", *(p
-1));
772 printf ("%d:\tend of pattern.\n", p
- start
);
777 print_compiled_pattern (bufp
)
778 struct re_pattern_buffer
*bufp
;
780 unsigned char *buffer
= bufp
->buffer
;
782 print_partial_compiled_pattern (buffer
, buffer
+ bufp
->used
);
783 printf ("%d bytes used/%d bytes allocated.\n", bufp
->used
, bufp
->allocated
);
785 if (bufp
->fastmap_accurate
&& bufp
->fastmap
)
787 printf ("fastmap: ");
788 print_fastmap (bufp
->fastmap
);
791 printf ("re_nsub: %d\t", bufp
->re_nsub
);
792 printf ("regs_alloc: %d\t", bufp
->regs_allocated
);
793 printf ("can_be_null: %d\t", bufp
->can_be_null
);
794 printf ("newline_anchor: %d\n", bufp
->newline_anchor
);
795 printf ("no_sub: %d\t", bufp
->no_sub
);
796 printf ("not_bol: %d\t", bufp
->not_bol
);
797 printf ("not_eol: %d\t", bufp
->not_eol
);
798 printf ("syntax: %d\n", bufp
->syntax
);
799 /* Perhaps we should print the translate table? */
804 print_double_string (where
, string1
, size1
, string2
, size2
)
817 if (FIRST_STRING_P (where
))
819 for (this_char
= where
- string1
; this_char
< size1
; this_char
++)
820 printchar (string1
[this_char
]);
825 for (this_char
= where
- string2
; this_char
< size2
; this_char
++)
826 printchar (string2
[this_char
]);
830 #else /* not DEBUG */
835 #define DEBUG_STATEMENT(e)
836 #define DEBUG_PRINT1(x)
837 #define DEBUG_PRINT2(x1, x2)
838 #define DEBUG_PRINT3(x1, x2, x3)
839 #define DEBUG_PRINT4(x1, x2, x3, x4)
840 #define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
841 #define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
843 #endif /* not DEBUG */
845 /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
846 also be assigned to arbitrarily: each pattern buffer stores its own
847 syntax, so it can be changed between regex compilations. */
848 reg_syntax_t re_syntax_options
= RE_SYNTAX_EMACS
;
851 /* Specify the precise syntax of regexps for compilation. This provides
852 for compatibility for various utilities which historically have
853 different, incompatible syntaxes.
855 The argument SYNTAX is a bit mask comprised of the various bits
856 defined in regex.h. We return the old syntax. */
859 re_set_syntax (syntax
)
862 reg_syntax_t ret
= re_syntax_options
;
864 re_syntax_options
= syntax
;
868 /* This table gives an error message for each of the error codes listed
869 in regex.h. Obviously the order here has to be same as there. */
871 static const char *re_error_msg
[] =
872 { NULL
, /* REG_NOERROR */
873 "No match", /* REG_NOMATCH */
874 "Invalid regular expression", /* REG_BADPAT */
875 "Invalid collation character", /* REG_ECOLLATE */
876 "Invalid character class name", /* REG_ECTYPE */
877 "Trailing backslash", /* REG_EESCAPE */
878 "Invalid back reference", /* REG_ESUBREG */
879 "Unmatched [ or [^", /* REG_EBRACK */
880 "Unmatched ( or \\(", /* REG_EPAREN */
881 "Unmatched \\{", /* REG_EBRACE */
882 "Invalid content of \\{\\}", /* REG_BADBR */
883 "Invalid range end", /* REG_ERANGE */
884 "Memory exhausted", /* REG_ESPACE */
885 "Invalid preceding regular expression", /* REG_BADRPT */
886 "Premature end of regular expression", /* REG_EEND */
887 "Regular expression too big", /* REG_ESIZE */
888 "Unmatched ) or \\)", /* REG_ERPAREN */
891 /* Avoiding alloca during matching, to placate r_alloc. */
893 /* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
894 searching and matching functions should not call alloca. On some
895 systems, alloca is implemented in terms of malloc, and if we're
896 using the relocating allocator routines, then malloc could cause a
897 relocation, which might (if the strings being searched are in the
898 ralloc heap) shift the data out from underneath the regexp
901 Here's another reason to avoid allocation: Emacs insists on
902 processing input from X in a signal handler; processing X input may
903 call malloc; if input arrives while a matching routine is calling
904 malloc, then we're scrod. But Emacs can't just block input while
905 calling matching routines; then we don't notice interrupts when
906 they come in. So, Emacs blocks input around all regexp calls
907 except the matching calls, which it leaves unprotected, in the
908 faith that they will not malloc. */
910 /* Normally, this is fine. */
911 #define MATCH_MAY_ALLOCATE
913 /* But under some circumstances, it's not. */
914 #if defined (emacs) || (defined (REL_ALLOC) && defined (C_ALLOCA))
915 #undef MATCH_MAY_ALLOCATE
919 /* Failure stack declarations and macros; both re_compile_fastmap and
920 re_match_2 use a failure stack. These have to be macros because of
924 /* Number of failure points for which to initially allocate space
925 when matching. If this number is exceeded, we allocate more
926 space, so it is not a hard limit. */
927 #ifndef INIT_FAILURE_ALLOC
928 #define INIT_FAILURE_ALLOC 5
931 /* Roughly the maximum number of failure points on the stack. Would be
932 exactly that if always used MAX_FAILURE_SPACE each time we failed.
933 This is a variable only so users of regex can assign to it; we never
934 change it ourselves. */
935 int re_max_failures
= 2000;
937 typedef unsigned char *fail_stack_elt_t
;
941 fail_stack_elt_t
*stack
;
943 unsigned avail
; /* Offset of next open position. */
946 #define FAIL_STACK_EMPTY() (fail_stack.avail == 0)
947 #define FAIL_STACK_PTR_EMPTY() (fail_stack_ptr->avail == 0)
948 #define FAIL_STACK_FULL() (fail_stack.avail == fail_stack.size)
949 #define FAIL_STACK_TOP() (fail_stack.stack[fail_stack.avail])
952 /* Initialize `fail_stack'. Do `return -2' if the alloc fails. */
954 #ifdef MATCH_MAY_ALLOCATE
955 #define INIT_FAIL_STACK() \
957 fail_stack.stack = (fail_stack_elt_t *) \
958 REGEX_ALLOCATE (INIT_FAILURE_ALLOC * sizeof (fail_stack_elt_t)); \
960 if (fail_stack.stack == NULL) \
963 fail_stack.size = INIT_FAILURE_ALLOC; \
964 fail_stack.avail = 0; \
967 #define INIT_FAIL_STACK() \
969 fail_stack.avail = 0; \
974 /* Double the size of FAIL_STACK, up to approximately `re_max_failures' items.
976 Return 1 if succeeds, and 0 if either ran out of memory
977 allocating space for it or it was already too large.
979 REGEX_REALLOCATE requires `destination' be declared. */
981 #define DOUBLE_FAIL_STACK(fail_stack) \
982 ((fail_stack).size > re_max_failures * MAX_FAILURE_ITEMS \
984 : ((fail_stack).stack = (fail_stack_elt_t *) \
985 REGEX_REALLOCATE ((fail_stack).stack, \
986 (fail_stack).size * sizeof (fail_stack_elt_t), \
987 ((fail_stack).size << 1) * sizeof (fail_stack_elt_t)), \
989 (fail_stack).stack == NULL \
991 : ((fail_stack).size <<= 1, \
995 /* Push PATTERN_OP on FAIL_STACK.
997 Return 1 if was able to do so and 0 if ran out of memory allocating
999 #define PUSH_PATTERN_OP(pattern_op, fail_stack) \
1000 ((FAIL_STACK_FULL () \
1001 && !DOUBLE_FAIL_STACK (fail_stack)) \
1003 : ((fail_stack).stack[(fail_stack).avail++] = pattern_op, \
1006 /* This pushes an item onto the failure stack. Must be a four-byte
1007 value. Assumes the variable `fail_stack'. Probably should only
1008 be called from within `PUSH_FAILURE_POINT'. */
1009 #define PUSH_FAILURE_ITEM(item) \
1010 fail_stack.stack[fail_stack.avail++] = (fail_stack_elt_t) item
1012 /* The complement operation. Assumes `fail_stack' is nonempty. */
1013 #define POP_FAILURE_ITEM() fail_stack.stack[--fail_stack.avail]
1015 /* Used to omit pushing failure point id's when we're not debugging. */
1017 #define DEBUG_PUSH PUSH_FAILURE_ITEM
1018 #define DEBUG_POP(item_addr) *(item_addr) = POP_FAILURE_ITEM ()
1020 #define DEBUG_PUSH(item)
1021 #define DEBUG_POP(item_addr)
1025 /* Push the information about the state we will need
1026 if we ever fail back to it.
1028 Requires variables fail_stack, regstart, regend, reg_info, and
1029 num_regs be declared. DOUBLE_FAIL_STACK requires `destination' be
1032 Does `return FAILURE_CODE' if runs out of memory. */
1034 #define PUSH_FAILURE_POINT(pattern_place, string_place, failure_code) \
1036 char *destination; \
1037 /* Must be int, so when we don't save any registers, the arithmetic \
1038 of 0 + -1 isn't done as unsigned. */ \
1041 DEBUG_STATEMENT (failure_id++); \
1042 DEBUG_STATEMENT (nfailure_points_pushed++); \
1043 DEBUG_PRINT2 ("\nPUSH_FAILURE_POINT #%u:\n", failure_id); \
1044 DEBUG_PRINT2 (" Before push, next avail: %d\n", (fail_stack).avail);\
1045 DEBUG_PRINT2 (" size: %d\n", (fail_stack).size);\
1047 DEBUG_PRINT2 (" slots needed: %d\n", NUM_FAILURE_ITEMS); \
1048 DEBUG_PRINT2 (" available: %d\n", REMAINING_AVAIL_SLOTS); \
1050 /* Ensure we have enough space allocated for what we will push. */ \
1051 while (REMAINING_AVAIL_SLOTS < NUM_FAILURE_ITEMS) \
1053 if (!DOUBLE_FAIL_STACK (fail_stack)) \
1054 return failure_code; \
1056 DEBUG_PRINT2 ("\n Doubled stack; size now: %d\n", \
1057 (fail_stack).size); \
1058 DEBUG_PRINT2 (" slots available: %d\n", REMAINING_AVAIL_SLOTS);\
1061 /* Push the info, starting with the registers. */ \
1062 DEBUG_PRINT1 ("\n"); \
1064 for (this_reg = lowest_active_reg; this_reg <= highest_active_reg; \
1067 DEBUG_PRINT2 (" Pushing reg: %d\n", this_reg); \
1068 DEBUG_STATEMENT (num_regs_pushed++); \
1070 DEBUG_PRINT2 (" start: 0x%x\n", regstart[this_reg]); \
1071 PUSH_FAILURE_ITEM (regstart[this_reg]); \
1073 DEBUG_PRINT2 (" end: 0x%x\n", regend[this_reg]); \
1074 PUSH_FAILURE_ITEM (regend[this_reg]); \
1076 DEBUG_PRINT2 (" info: 0x%x\n ", reg_info[this_reg]); \
1077 DEBUG_PRINT2 (" match_null=%d", \
1078 REG_MATCH_NULL_STRING_P (reg_info[this_reg])); \
1079 DEBUG_PRINT2 (" active=%d", IS_ACTIVE (reg_info[this_reg])); \
1080 DEBUG_PRINT2 (" matched_something=%d", \
1081 MATCHED_SOMETHING (reg_info[this_reg])); \
1082 DEBUG_PRINT2 (" ever_matched=%d", \
1083 EVER_MATCHED_SOMETHING (reg_info[this_reg])); \
1084 DEBUG_PRINT1 ("\n"); \
1085 PUSH_FAILURE_ITEM (reg_info[this_reg].word); \
1088 DEBUG_PRINT2 (" Pushing low active reg: %d\n", lowest_active_reg);\
1089 PUSH_FAILURE_ITEM (lowest_active_reg); \
1091 DEBUG_PRINT2 (" Pushing high active reg: %d\n", highest_active_reg);\
1092 PUSH_FAILURE_ITEM (highest_active_reg); \
1094 DEBUG_PRINT2 (" Pushing pattern 0x%x: ", pattern_place); \
1095 DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern_place, pend); \
1096 PUSH_FAILURE_ITEM (pattern_place); \
1098 DEBUG_PRINT2 (" Pushing string 0x%x: `", string_place); \
1099 DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2, \
1101 DEBUG_PRINT1 ("'\n"); \
1102 PUSH_FAILURE_ITEM (string_place); \
1104 DEBUG_PRINT2 (" Pushing failure id: %u\n", failure_id); \
1105 DEBUG_PUSH (failure_id); \
1108 /* This is the number of items that are pushed and popped on the stack
1109 for each register. */
1110 #define NUM_REG_ITEMS 3
1112 /* Individual items aside from the registers. */
1114 #define NUM_NONREG_ITEMS 5 /* Includes failure point id. */
1116 #define NUM_NONREG_ITEMS 4
1119 /* We push at most this many items on the stack. */
1120 #define MAX_FAILURE_ITEMS ((num_regs - 1) * NUM_REG_ITEMS + NUM_NONREG_ITEMS)
1122 /* We actually push this many items. */
1123 #define NUM_FAILURE_ITEMS \
1124 ((highest_active_reg - lowest_active_reg + 1) * NUM_REG_ITEMS \
1127 /* How many items can still be added to the stack without overflowing it. */
1128 #define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
1131 /* Pops what PUSH_FAIL_STACK pushes.
1133 We restore into the parameters, all of which should be lvalues:
1134 STR -- the saved data position.
1135 PAT -- the saved pattern position.
1136 LOW_REG, HIGH_REG -- the highest and lowest active registers.
1137 REGSTART, REGEND -- arrays of string positions.
1138 REG_INFO -- array of information about each subexpression.
1140 Also assumes the variables `fail_stack' and (if debugging), `bufp',
1141 `pend', `string1', `size1', `string2', and `size2'. */
1143 #define POP_FAILURE_POINT(str, pat, low_reg, high_reg, regstart, regend, reg_info)\
1145 DEBUG_STATEMENT (fail_stack_elt_t failure_id;) \
1147 const unsigned char *string_temp; \
1149 assert (!FAIL_STACK_EMPTY ()); \
1151 /* Remove failure points and point to how many regs pushed. */ \
1152 DEBUG_PRINT1 ("POP_FAILURE_POINT:\n"); \
1153 DEBUG_PRINT2 (" Before pop, next avail: %d\n", fail_stack.avail); \
1154 DEBUG_PRINT2 (" size: %d\n", fail_stack.size); \
1156 assert (fail_stack.avail >= NUM_NONREG_ITEMS); \
1158 DEBUG_POP (&failure_id); \
1159 DEBUG_PRINT2 (" Popping failure id: %u\n", failure_id); \
1161 /* If the saved string location is NULL, it came from an \
1162 on_failure_keep_string_jump opcode, and we want to throw away the \
1163 saved NULL, thus retaining our current position in the string. */ \
1164 string_temp = POP_FAILURE_ITEM (); \
1165 if (string_temp != NULL) \
1166 str = (const char *) string_temp; \
1168 DEBUG_PRINT2 (" Popping string 0x%x: `", str); \
1169 DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2); \
1170 DEBUG_PRINT1 ("'\n"); \
1172 pat = (unsigned char *) POP_FAILURE_ITEM (); \
1173 DEBUG_PRINT2 (" Popping pattern 0x%x: ", pat); \
1174 DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend); \
1176 /* Restore register info. */ \
1177 high_reg = (unsigned) POP_FAILURE_ITEM (); \
1178 DEBUG_PRINT2 (" Popping high active reg: %d\n", high_reg); \
1180 low_reg = (unsigned) POP_FAILURE_ITEM (); \
1181 DEBUG_PRINT2 (" Popping low active reg: %d\n", low_reg); \
1183 for (this_reg = high_reg; this_reg >= low_reg; this_reg--) \
1185 DEBUG_PRINT2 (" Popping reg: %d\n", this_reg); \
1187 reg_info[this_reg].word = POP_FAILURE_ITEM (); \
1188 DEBUG_PRINT2 (" info: 0x%x\n", reg_info[this_reg]); \
1190 regend[this_reg] = (const char *) POP_FAILURE_ITEM (); \
1191 DEBUG_PRINT2 (" end: 0x%x\n", regend[this_reg]); \
1193 regstart[this_reg] = (const char *) POP_FAILURE_ITEM (); \
1194 DEBUG_PRINT2 (" start: 0x%x\n", regstart[this_reg]); \
1197 DEBUG_STATEMENT (nfailure_points_popped++); \
1198 } /* POP_FAILURE_POINT */
1202 /* Structure for per-register (a.k.a. per-group) information.
1203 This must not be longer than one word, because we push this value
1204 onto the failure stack. Other register information, such as the
1205 starting and ending positions (which are addresses), and the list of
1206 inner groups (which is a bits list) are maintained in separate
1209 We are making a (strictly speaking) nonportable assumption here: that
1210 the compiler will pack our bit fields into something that fits into
1211 the type of `word', i.e., is something that fits into one item on the
1215 fail_stack_elt_t word
;
1218 /* This field is one if this group can match the empty string,
1219 zero if not. If not yet determined, `MATCH_NULL_UNSET_VALUE'. */
1220 #define MATCH_NULL_UNSET_VALUE 3
1221 unsigned match_null_string_p
: 2;
1222 unsigned is_active
: 1;
1223 unsigned matched_something
: 1;
1224 unsigned ever_matched_something
: 1;
1226 } register_info_type
;
1228 #define REG_MATCH_NULL_STRING_P(R) ((R).bits.match_null_string_p)
1229 #define IS_ACTIVE(R) ((R).bits.is_active)
1230 #define MATCHED_SOMETHING(R) ((R).bits.matched_something)
1231 #define EVER_MATCHED_SOMETHING(R) ((R).bits.ever_matched_something)
1234 /* Call this when have matched a real character; it sets `matched' flags
1235 for the subexpressions which we are currently inside. Also records
1236 that those subexprs have matched. */
1237 #define SET_REGS_MATCHED() \
1241 for (r = lowest_active_reg; r <= highest_active_reg; r++) \
1243 MATCHED_SOMETHING (reg_info[r]) \
1244 = EVER_MATCHED_SOMETHING (reg_info[r]) \
1251 /* Registers are set to a sentinel when they haven't yet matched. */
1252 #define REG_UNSET_VALUE ((char *) -1)
1253 #define REG_UNSET(e) ((e) == REG_UNSET_VALUE)
1257 /* How do we implement a missing MATCH_MAY_ALLOCATE?
1258 We make the fail stack a global thing, and then grow it to
1259 re_max_failures when we compile. */
1260 #ifndef MATCH_MAY_ALLOCATE
1261 static fail_stack_type fail_stack
;
1263 static const char ** regstart
, ** regend
;
1264 static const char ** old_regstart
, ** old_regend
;
1265 static const char **best_regstart
, **best_regend
;
1266 static register_info_type
*reg_info
;
1267 static const char **reg_dummy
;
1268 static register_info_type
*reg_info_dummy
;
1272 /* Subroutine declarations and macros for regex_compile. */
1274 static void store_op1 (), store_op2 ();
1275 static void insert_op1 (), insert_op2 ();
1276 static boolean
at_begline_loc_p (), at_endline_loc_p ();
1277 static boolean
group_in_compile_stack ();
1278 static reg_errcode_t
compile_range ();
1280 /* Fetch the next character in the uncompiled pattern---translating it
1281 if necessary. Also cast from a signed character in the constant
1282 string passed to us by the user to an unsigned char that we can use
1283 as an array index (in, e.g., `translate'). */
1284 #define PATFETCH(c) \
1285 do {if (p == pend) return REG_EEND; \
1286 c = (unsigned char) *p++; \
1287 if (translate) c = translate[c]; \
1290 /* Fetch the next character in the uncompiled pattern, with no
1292 #define PATFETCH_RAW(c) \
1293 do {if (p == pend) return REG_EEND; \
1294 c = (unsigned char) *p++; \
1297 /* Go backwards one character in the pattern. */
1298 #define PATUNFETCH p--
1301 /* If `translate' is non-null, return translate[D], else just D. We
1302 cast the subscript to translate because some data is declared as
1303 `char *', to avoid warnings when a string constant is passed. But
1304 when we use a character as a subscript we must make it unsigned. */
1305 #define TRANSLATE(d) (translate ? translate[(unsigned char) (d)] : (d))
1308 /* Macros for outputting the compiled pattern into `buffer'. */
1310 /* If the buffer isn't allocated when it comes in, use this. */
1311 #define INIT_BUF_SIZE 32
1313 /* Make sure we have at least N more bytes of space in buffer. */
1314 #define GET_BUFFER_SPACE(n) \
1315 while (b - bufp->buffer + (n) > bufp->allocated) \
1318 /* Make sure we have one more byte of buffer space and then add C to it. */
1319 #define BUF_PUSH(c) \
1321 GET_BUFFER_SPACE (1); \
1322 *b++ = (unsigned char) (c); \
1326 /* Ensure we have two more bytes of buffer space and then append C1 and C2. */
1327 #define BUF_PUSH_2(c1, c2) \
1329 GET_BUFFER_SPACE (2); \
1330 *b++ = (unsigned char) (c1); \
1331 *b++ = (unsigned char) (c2); \
1335 /* As with BUF_PUSH_2, except for three bytes. */
1336 #define BUF_PUSH_3(c1, c2, c3) \
1338 GET_BUFFER_SPACE (3); \
1339 *b++ = (unsigned char) (c1); \
1340 *b++ = (unsigned char) (c2); \
1341 *b++ = (unsigned char) (c3); \
1345 /* Store a jump with opcode OP at LOC to location TO. We store a
1346 relative address offset by the three bytes the jump itself occupies. */
1347 #define STORE_JUMP(op, loc, to) \
1348 store_op1 (op, loc, (to) - (loc) - 3)
1350 /* Likewise, for a two-argument jump. */
1351 #define STORE_JUMP2(op, loc, to, arg) \
1352 store_op2 (op, loc, (to) - (loc) - 3, arg)
1354 /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
1355 #define INSERT_JUMP(op, loc, to) \
1356 insert_op1 (op, loc, (to) - (loc) - 3, b)
1358 /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
1359 #define INSERT_JUMP2(op, loc, to, arg) \
1360 insert_op2 (op, loc, (to) - (loc) - 3, arg, b)
1363 /* This is not an arbitrary limit: the arguments which represent offsets
1364 into the pattern are two bytes long. So if 2^16 bytes turns out to
1365 be too small, many things would have to change. */
1366 #define MAX_BUF_SIZE (1L << 16)
1369 /* Extend the buffer by twice its current size via realloc and
1370 reset the pointers that pointed into the old block to point to the
1371 correct places in the new one. If extending the buffer results in it
1372 being larger than MAX_BUF_SIZE, then flag memory exhausted. */
1373 #define EXTEND_BUFFER() \
1375 unsigned char *old_buffer = bufp->buffer; \
1376 if (bufp->allocated == MAX_BUF_SIZE) \
1378 bufp->allocated <<= 1; \
1379 if (bufp->allocated > MAX_BUF_SIZE) \
1380 bufp->allocated = MAX_BUF_SIZE; \
1381 bufp->buffer = (unsigned char *) realloc (bufp->buffer, bufp->allocated);\
1382 if (bufp->buffer == NULL) \
1383 return REG_ESPACE; \
1384 /* If the buffer moved, move all the pointers into it. */ \
1385 if (old_buffer != bufp->buffer) \
1387 b = (b - old_buffer) + bufp->buffer; \
1388 begalt = (begalt - old_buffer) + bufp->buffer; \
1389 if (fixup_alt_jump) \
1390 fixup_alt_jump = (fixup_alt_jump - old_buffer) + bufp->buffer;\
1392 laststart = (laststart - old_buffer) + bufp->buffer; \
1393 if (pending_exact) \
1394 pending_exact = (pending_exact - old_buffer) + bufp->buffer; \
1399 /* Since we have one byte reserved for the register number argument to
1400 {start,stop}_memory, the maximum number of groups we can report
1401 things about is what fits in that byte. */
1402 #define MAX_REGNUM 255
1404 /* But patterns can have more than `MAX_REGNUM' registers. We just
1405 ignore the excess. */
1406 typedef unsigned regnum_t
;
1409 /* Macros for the compile stack. */
1411 /* Since offsets can go either forwards or backwards, this type needs to
1412 be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
1413 typedef int pattern_offset_t
;
1417 pattern_offset_t begalt_offset
;
1418 pattern_offset_t fixup_alt_jump
;
1419 pattern_offset_t inner_group_offset
;
1420 pattern_offset_t laststart_offset
;
1422 } compile_stack_elt_t
;
1427 compile_stack_elt_t
*stack
;
1429 unsigned avail
; /* Offset of next open position. */
1430 } compile_stack_type
;
1433 #define INIT_COMPILE_STACK_SIZE 32
1435 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
1436 #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
1438 /* The next available element. */
1439 #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
1442 /* Set the bit for character C in a list. */
1443 #define SET_LIST_BIT(c) \
1444 (b[((unsigned char) (c)) / BYTEWIDTH] \
1445 |= 1 << (((unsigned char) c) % BYTEWIDTH))
1448 /* Get the next unsigned number in the uncompiled pattern. */
1449 #define GET_UNSIGNED_NUMBER(num) \
1453 while (ISDIGIT (c)) \
1457 num = num * 10 + c - '0'; \
1465 #define CHAR_CLASS_MAX_LENGTH 6 /* Namely, `xdigit'. */
1467 #define IS_CHAR_CLASS(string) \
1468 (STREQ (string, "alpha") || STREQ (string, "upper") \
1469 || STREQ (string, "lower") || STREQ (string, "digit") \
1470 || STREQ (string, "alnum") || STREQ (string, "xdigit") \
1471 || STREQ (string, "space") || STREQ (string, "print") \
1472 || STREQ (string, "punct") || STREQ (string, "graph") \
1473 || STREQ (string, "cntrl") || STREQ (string, "blank"))
1475 /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
1476 Returns one of error codes defined in `regex.h', or zero for success.
1478 Assumes the `allocated' (and perhaps `buffer') and `translate'
1479 fields are set in BUFP on entry.
1481 If it succeeds, results are put in BUFP (if it returns an error, the
1482 contents of BUFP are undefined):
1483 `buffer' is the compiled pattern;
1484 `syntax' is set to SYNTAX;
1485 `used' is set to the length of the compiled pattern;
1486 `fastmap_accurate' is zero;
1487 `re_nsub' is the number of subexpressions in PATTERN;
1488 `not_bol' and `not_eol' are zero;
1490 The `fastmap' and `newline_anchor' fields are neither
1491 examined nor set. */
1493 static reg_errcode_t
1494 regex_compile (pattern
, size
, syntax
, bufp
)
1495 const char *pattern
;
1497 reg_syntax_t syntax
;
1498 struct re_pattern_buffer
*bufp
;
1500 /* We fetch characters from PATTERN here. Even though PATTERN is
1501 `char *' (i.e., signed), we declare these variables as unsigned, so
1502 they can be reliably used as array indices. */
1503 register unsigned char c
, c1
;
1505 /* A random temporary spot in PATTERN. */
1508 /* Points to the end of the buffer, where we should append. */
1509 register unsigned char *b
;
1511 /* Keeps track of unclosed groups. */
1512 compile_stack_type compile_stack
;
1514 /* Points to the current (ending) position in the pattern. */
1515 const char *p
= pattern
;
1516 const char *pend
= pattern
+ size
;
1518 /* How to translate the characters in the pattern. */
1519 char *translate
= bufp
->translate
;
1521 /* Address of the count-byte of the most recently inserted `exactn'
1522 command. This makes it possible to tell if a new exact-match
1523 character can be added to that command or if the character requires
1524 a new `exactn' command. */
1525 unsigned char *pending_exact
= 0;
1527 /* Address of start of the most recently finished expression.
1528 This tells, e.g., postfix * where to find the start of its
1529 operand. Reset at the beginning of groups and alternatives. */
1530 unsigned char *laststart
= 0;
1532 /* Address of beginning of regexp, or inside of last group. */
1533 unsigned char *begalt
;
1535 /* Place in the uncompiled pattern (i.e., the {) to
1536 which to go back if the interval is invalid. */
1537 const char *beg_interval
;
1539 /* Address of the place where a forward jump should go to the end of
1540 the containing expression. Each alternative of an `or' -- except the
1541 last -- ends with a forward jump of this sort. */
1542 unsigned char *fixup_alt_jump
= 0;
1544 /* Counts open-groups as they are encountered. Remembered for the
1545 matching close-group on the compile stack, so the same register
1546 number is put in the stop_memory as the start_memory. */
1547 regnum_t regnum
= 0;
1550 DEBUG_PRINT1 ("\nCompiling pattern: ");
1553 unsigned debug_count
;
1555 for (debug_count
= 0; debug_count
< size
; debug_count
++)
1556 printchar (pattern
[debug_count
]);
1561 /* Initialize the compile stack. */
1562 compile_stack
.stack
= TALLOC (INIT_COMPILE_STACK_SIZE
, compile_stack_elt_t
);
1563 if (compile_stack
.stack
== NULL
)
1566 compile_stack
.size
= INIT_COMPILE_STACK_SIZE
;
1567 compile_stack
.avail
= 0;
1569 /* Initialize the pattern buffer. */
1570 bufp
->syntax
= syntax
;
1571 bufp
->fastmap_accurate
= 0;
1572 bufp
->not_bol
= bufp
->not_eol
= 0;
1574 /* Set `used' to zero, so that if we return an error, the pattern
1575 printer (for debugging) will think there's no pattern. We reset it
1579 /* Always count groups, whether or not bufp->no_sub is set. */
1582 #if !defined (emacs) && !defined (SYNTAX_TABLE)
1583 /* Initialize the syntax table. */
1584 init_syntax_once ();
1587 if (bufp
->allocated
== 0)
1590 { /* If zero allocated, but buffer is non-null, try to realloc
1591 enough space. This loses if buffer's address is bogus, but
1592 that is the user's responsibility. */
1593 RETALLOC (bufp
->buffer
, INIT_BUF_SIZE
, unsigned char);
1596 { /* Caller did not allocate a buffer. Do it for them. */
1597 bufp
->buffer
= TALLOC (INIT_BUF_SIZE
, unsigned char);
1599 if (!bufp
->buffer
) return REG_ESPACE
;
1601 bufp
->allocated
= INIT_BUF_SIZE
;
1604 begalt
= b
= bufp
->buffer
;
1606 /* Loop through the uncompiled pattern until we're at the end. */
1615 if ( /* If at start of pattern, it's an operator. */
1617 /* If context independent, it's an operator. */
1618 || syntax
& RE_CONTEXT_INDEP_ANCHORS
1619 /* Otherwise, depends on what's come before. */
1620 || at_begline_loc_p (pattern
, p
, syntax
))
1630 if ( /* If at end of pattern, it's an operator. */
1632 /* If context independent, it's an operator. */
1633 || syntax
& RE_CONTEXT_INDEP_ANCHORS
1634 /* Otherwise, depends on what's next. */
1635 || at_endline_loc_p (p
, pend
, syntax
))
1645 if ((syntax
& RE_BK_PLUS_QM
)
1646 || (syntax
& RE_LIMITED_OPS
))
1650 /* If there is no previous pattern... */
1653 if (syntax
& RE_CONTEXT_INVALID_OPS
)
1655 else if (!(syntax
& RE_CONTEXT_INDEP_OPS
))
1660 /* Are we optimizing this jump? */
1661 boolean keep_string_p
= false;
1663 /* 1 means zero (many) matches is allowed. */
1664 char zero_times_ok
= 0, many_times_ok
= 0;
1666 /* If there is a sequence of repetition chars, collapse it
1667 down to just one (the right one). We can't combine
1668 interval operators with these because of, e.g., `a{2}*',
1669 which should only match an even number of `a's. */
1673 zero_times_ok
|= c
!= '+';
1674 many_times_ok
|= c
!= '?';
1682 || (!(syntax
& RE_BK_PLUS_QM
) && (c
== '+' || c
== '?')))
1685 else if (syntax
& RE_BK_PLUS_QM
&& c
== '\\')
1687 if (p
== pend
) return REG_EESCAPE
;
1690 if (!(c1
== '+' || c1
== '?'))
1705 /* If we get here, we found another repeat character. */
1708 /* Star, etc. applied to an empty pattern is equivalent
1709 to an empty pattern. */
1713 /* Now we know whether or not zero matches is allowed
1714 and also whether or not two or more matches is allowed. */
1716 { /* More than one repetition is allowed, so put in at the
1717 end a backward relative jump from `b' to before the next
1718 jump we're going to put in below (which jumps from
1719 laststart to after this jump).
1721 But if we are at the `*' in the exact sequence `.*\n',
1722 insert an unconditional jump backwards to the .,
1723 instead of the beginning of the loop. This way we only
1724 push a failure point once, instead of every time
1725 through the loop. */
1726 assert (p
- 1 > pattern
);
1728 /* Allocate the space for the jump. */
1729 GET_BUFFER_SPACE (3);
1731 /* We know we are not at the first character of the pattern,
1732 because laststart was nonzero. And we've already
1733 incremented `p', by the way, to be the character after
1734 the `*'. Do we have to do something analogous here
1735 for null bytes, because of RE_DOT_NOT_NULL? */
1736 if (TRANSLATE (*(p
- 2)) == TRANSLATE ('.')
1738 && p
< pend
&& TRANSLATE (*p
) == TRANSLATE ('\n')
1739 && !(syntax
& RE_DOT_NEWLINE
))
1740 { /* We have .*\n. */
1741 STORE_JUMP (jump
, b
, laststart
);
1742 keep_string_p
= true;
1745 /* Anything else. */
1746 STORE_JUMP (maybe_pop_jump
, b
, laststart
- 3);
1748 /* We've added more stuff to the buffer. */
1752 /* On failure, jump from laststart to b + 3, which will be the
1753 end of the buffer after this jump is inserted. */
1754 GET_BUFFER_SPACE (3);
1755 INSERT_JUMP (keep_string_p
? on_failure_keep_string_jump
1763 /* At least one repetition is required, so insert a
1764 `dummy_failure_jump' before the initial
1765 `on_failure_jump' instruction of the loop. This
1766 effects a skip over that instruction the first time
1767 we hit that loop. */
1768 GET_BUFFER_SPACE (3);
1769 INSERT_JUMP (dummy_failure_jump
, laststart
, laststart
+ 6);
1784 boolean had_char_class
= false;
1786 if (p
== pend
) return REG_EBRACK
;
1788 /* Ensure that we have enough space to push a charset: the
1789 opcode, the length count, and the bitset; 34 bytes in all. */
1790 GET_BUFFER_SPACE (34);
1794 /* We test `*p == '^' twice, instead of using an if
1795 statement, so we only need one BUF_PUSH. */
1796 BUF_PUSH (*p
== '^' ? charset_not
: charset
);
1800 /* Remember the first position in the bracket expression. */
1803 /* Push the number of bytes in the bitmap. */
1804 BUF_PUSH ((1 << BYTEWIDTH
) / BYTEWIDTH
);
1806 /* Clear the whole map. */
1807 bzero (b
, (1 << BYTEWIDTH
) / BYTEWIDTH
);
1809 /* charset_not matches newline according to a syntax bit. */
1810 if ((re_opcode_t
) b
[-2] == charset_not
1811 && (syntax
& RE_HAT_LISTS_NOT_NEWLINE
))
1812 SET_LIST_BIT ('\n');
1814 /* Read in characters and ranges, setting map bits. */
1817 if (p
== pend
) return REG_EBRACK
;
1821 /* \ might escape characters inside [...] and [^...]. */
1822 if ((syntax
& RE_BACKSLASH_ESCAPE_IN_LISTS
) && c
== '\\')
1824 if (p
== pend
) return REG_EESCAPE
;
1831 /* Could be the end of the bracket expression. If it's
1832 not (i.e., when the bracket expression is `[]' so
1833 far), the ']' character bit gets set way below. */
1834 if (c
== ']' && p
!= p1
+ 1)
1837 /* Look ahead to see if it's a range when the last thing
1838 was a character class. */
1839 if (had_char_class
&& c
== '-' && *p
!= ']')
1842 /* Look ahead to see if it's a range when the last thing
1843 was a character: if this is a hyphen not at the
1844 beginning or the end of a list, then it's the range
1847 && !(p
- 2 >= pattern
&& p
[-2] == '[')
1848 && !(p
- 3 >= pattern
&& p
[-3] == '[' && p
[-2] == '^')
1852 = compile_range (&p
, pend
, translate
, syntax
, b
);
1853 if (ret
!= REG_NOERROR
) return ret
;
1856 else if (p
[0] == '-' && p
[1] != ']')
1857 { /* This handles ranges made up of characters only. */
1860 /* Move past the `-'. */
1863 ret
= compile_range (&p
, pend
, translate
, syntax
, b
);
1864 if (ret
!= REG_NOERROR
) return ret
;
1867 /* See if we're at the beginning of a possible character
1870 else if (syntax
& RE_CHAR_CLASSES
&& c
== '[' && *p
== ':')
1871 { /* Leave room for the null. */
1872 char str
[CHAR_CLASS_MAX_LENGTH
+ 1];
1877 /* If pattern is `[[:'. */
1878 if (p
== pend
) return REG_EBRACK
;
1883 if (c
== ':' || c
== ']' || p
== pend
1884 || c1
== CHAR_CLASS_MAX_LENGTH
)
1890 /* If isn't a word bracketed by `[:' and:`]':
1891 undo the ending character, the letters, and leave
1892 the leading `:' and `[' (but set bits for them). */
1893 if (c
== ':' && *p
== ']')
1896 boolean is_alnum
= STREQ (str
, "alnum");
1897 boolean is_alpha
= STREQ (str
, "alpha");
1898 boolean is_blank
= STREQ (str
, "blank");
1899 boolean is_cntrl
= STREQ (str
, "cntrl");
1900 boolean is_digit
= STREQ (str
, "digit");
1901 boolean is_graph
= STREQ (str
, "graph");
1902 boolean is_lower
= STREQ (str
, "lower");
1903 boolean is_print
= STREQ (str
, "print");
1904 boolean is_punct
= STREQ (str
, "punct");
1905 boolean is_space
= STREQ (str
, "space");
1906 boolean is_upper
= STREQ (str
, "upper");
1907 boolean is_xdigit
= STREQ (str
, "xdigit");
1909 if (!IS_CHAR_CLASS (str
)) return REG_ECTYPE
;
1911 /* Throw away the ] at the end of the character
1915 if (p
== pend
) return REG_EBRACK
;
1917 for (ch
= 0; ch
< 1 << BYTEWIDTH
; ch
++)
1919 if ( (is_alnum
&& ISALNUM (ch
))
1920 || (is_alpha
&& ISALPHA (ch
))
1921 || (is_blank
&& ISBLANK (ch
))
1922 || (is_cntrl
&& ISCNTRL (ch
))
1923 || (is_digit
&& ISDIGIT (ch
))
1924 || (is_graph
&& ISGRAPH (ch
))
1925 || (is_lower
&& ISLOWER (ch
))
1926 || (is_print
&& ISPRINT (ch
))
1927 || (is_punct
&& ISPUNCT (ch
))
1928 || (is_space
&& ISSPACE (ch
))
1929 || (is_upper
&& ISUPPER (ch
))
1930 || (is_xdigit
&& ISXDIGIT (ch
)))
1933 had_char_class
= true;
1942 had_char_class
= false;
1947 had_char_class
= false;
1952 /* Discard any (non)matching list bytes that are all 0 at the
1953 end of the map. Decrease the map-length byte too. */
1954 while ((int) b
[-1] > 0 && b
[b
[-1] - 1] == 0)
1962 if (syntax
& RE_NO_BK_PARENS
)
1969 if (syntax
& RE_NO_BK_PARENS
)
1976 if (syntax
& RE_NEWLINE_ALT
)
1983 if (syntax
& RE_NO_BK_VBAR
)
1990 if (syntax
& RE_INTERVALS
&& syntax
& RE_NO_BK_BRACES
)
1991 goto handle_interval
;
1997 if (p
== pend
) return REG_EESCAPE
;
1999 /* Do not translate the character after the \, so that we can
2000 distinguish, e.g., \B from \b, even if we normally would
2001 translate, e.g., B to b. */
2007 if (syntax
& RE_NO_BK_PARENS
)
2008 goto normal_backslash
;
2014 if (COMPILE_STACK_FULL
)
2016 RETALLOC (compile_stack
.stack
, compile_stack
.size
<< 1,
2017 compile_stack_elt_t
);
2018 if (compile_stack
.stack
== NULL
) return REG_ESPACE
;
2020 compile_stack
.size
<<= 1;
2023 /* These are the values to restore when we hit end of this
2024 group. They are all relative offsets, so that if the
2025 whole pattern moves because of realloc, they will still
2027 COMPILE_STACK_TOP
.begalt_offset
= begalt
- bufp
->buffer
;
2028 COMPILE_STACK_TOP
.fixup_alt_jump
2029 = fixup_alt_jump
? fixup_alt_jump
- bufp
->buffer
+ 1 : 0;
2030 COMPILE_STACK_TOP
.laststart_offset
= b
- bufp
->buffer
;
2031 COMPILE_STACK_TOP
.regnum
= regnum
;
2033 /* We will eventually replace the 0 with the number of
2034 groups inner to this one. But do not push a
2035 start_memory for groups beyond the last one we can
2036 represent in the compiled pattern. */
2037 if (regnum
<= MAX_REGNUM
)
2039 COMPILE_STACK_TOP
.inner_group_offset
= b
- bufp
->buffer
+ 2;
2040 BUF_PUSH_3 (start_memory
, regnum
, 0);
2043 compile_stack
.avail
++;
2048 /* If we've reached MAX_REGNUM groups, then this open
2049 won't actually generate any code, so we'll have to
2050 clear pending_exact explicitly. */
2056 if (syntax
& RE_NO_BK_PARENS
) goto normal_backslash
;
2058 if (COMPILE_STACK_EMPTY
)
2059 if (syntax
& RE_UNMATCHED_RIGHT_PAREN_ORD
)
2060 goto normal_backslash
;
2066 { /* Push a dummy failure point at the end of the
2067 alternative for a possible future
2068 `pop_failure_jump' to pop. See comments at
2069 `push_dummy_failure' in `re_match_2'. */
2070 BUF_PUSH (push_dummy_failure
);
2072 /* We allocated space for this jump when we assigned
2073 to `fixup_alt_jump', in the `handle_alt' case below. */
2074 STORE_JUMP (jump_past_alt
, fixup_alt_jump
, b
- 1);
2077 /* See similar code for backslashed left paren above. */
2078 if (COMPILE_STACK_EMPTY
)
2079 if (syntax
& RE_UNMATCHED_RIGHT_PAREN_ORD
)
2084 /* Since we just checked for an empty stack above, this
2085 ``can't happen''. */
2086 assert (compile_stack
.avail
!= 0);
2088 /* We don't just want to restore into `regnum', because
2089 later groups should continue to be numbered higher,
2090 as in `(ab)c(de)' -- the second group is #2. */
2091 regnum_t this_group_regnum
;
2093 compile_stack
.avail
--;
2094 begalt
= bufp
->buffer
+ COMPILE_STACK_TOP
.begalt_offset
;
2096 = COMPILE_STACK_TOP
.fixup_alt_jump
2097 ? bufp
->buffer
+ COMPILE_STACK_TOP
.fixup_alt_jump
- 1
2099 laststart
= bufp
->buffer
+ COMPILE_STACK_TOP
.laststart_offset
;
2100 this_group_regnum
= COMPILE_STACK_TOP
.regnum
;
2101 /* If we've reached MAX_REGNUM groups, then this open
2102 won't actually generate any code, so we'll have to
2103 clear pending_exact explicitly. */
2106 /* We're at the end of the group, so now we know how many
2107 groups were inside this one. */
2108 if (this_group_regnum
<= MAX_REGNUM
)
2110 unsigned char *inner_group_loc
2111 = bufp
->buffer
+ COMPILE_STACK_TOP
.inner_group_offset
;
2113 *inner_group_loc
= regnum
- this_group_regnum
;
2114 BUF_PUSH_3 (stop_memory
, this_group_regnum
,
2115 regnum
- this_group_regnum
);
2121 case '|': /* `\|'. */
2122 if (syntax
& RE_LIMITED_OPS
|| syntax
& RE_NO_BK_VBAR
)
2123 goto normal_backslash
;
2125 if (syntax
& RE_LIMITED_OPS
)
2128 /* Insert before the previous alternative a jump which
2129 jumps to this alternative if the former fails. */
2130 GET_BUFFER_SPACE (3);
2131 INSERT_JUMP (on_failure_jump
, begalt
, b
+ 6);
2135 /* The alternative before this one has a jump after it
2136 which gets executed if it gets matched. Adjust that
2137 jump so it will jump to this alternative's analogous
2138 jump (put in below, which in turn will jump to the next
2139 (if any) alternative's such jump, etc.). The last such
2140 jump jumps to the correct final destination. A picture:
2146 If we are at `b', then fixup_alt_jump right now points to a
2147 three-byte space after `a'. We'll put in the jump, set
2148 fixup_alt_jump to right after `b', and leave behind three
2149 bytes which we'll fill in when we get to after `c'. */
2152 STORE_JUMP (jump_past_alt
, fixup_alt_jump
, b
);
2154 /* Mark and leave space for a jump after this alternative,
2155 to be filled in later either by next alternative or
2156 when know we're at the end of a series of alternatives. */
2158 GET_BUFFER_SPACE (3);
2167 /* If \{ is a literal. */
2168 if (!(syntax
& RE_INTERVALS
)
2169 /* If we're at `\{' and it's not the open-interval
2171 || ((syntax
& RE_INTERVALS
) && (syntax
& RE_NO_BK_BRACES
))
2172 || (p
- 2 == pattern
&& p
== pend
))
2173 goto normal_backslash
;
2177 /* If got here, then the syntax allows intervals. */
2179 /* At least (most) this many matches must be made. */
2180 int lower_bound
= -1, upper_bound
= -1;
2182 beg_interval
= p
- 1;
2186 if (syntax
& RE_NO_BK_BRACES
)
2187 goto unfetch_interval
;
2192 GET_UNSIGNED_NUMBER (lower_bound
);
2196 GET_UNSIGNED_NUMBER (upper_bound
);
2197 if (upper_bound
< 0) upper_bound
= RE_DUP_MAX
;
2200 /* Interval such as `{1}' => match exactly once. */
2201 upper_bound
= lower_bound
;
2203 if (lower_bound
< 0 || upper_bound
> RE_DUP_MAX
2204 || lower_bound
> upper_bound
)
2206 if (syntax
& RE_NO_BK_BRACES
)
2207 goto unfetch_interval
;
2212 if (!(syntax
& RE_NO_BK_BRACES
))
2214 if (c
!= '\\') return REG_EBRACE
;
2221 if (syntax
& RE_NO_BK_BRACES
)
2222 goto unfetch_interval
;
2227 /* We just parsed a valid interval. */
2229 /* If it's invalid to have no preceding re. */
2232 if (syntax
& RE_CONTEXT_INVALID_OPS
)
2234 else if (syntax
& RE_CONTEXT_INDEP_OPS
)
2237 goto unfetch_interval
;
2240 /* If the upper bound is zero, don't want to succeed at
2241 all; jump from `laststart' to `b + 3', which will be
2242 the end of the buffer after we insert the jump. */
2243 if (upper_bound
== 0)
2245 GET_BUFFER_SPACE (3);
2246 INSERT_JUMP (jump
, laststart
, b
+ 3);
2250 /* Otherwise, we have a nontrivial interval. When
2251 we're all done, the pattern will look like:
2252 set_number_at <jump count> <upper bound>
2253 set_number_at <succeed_n count> <lower bound>
2254 succeed_n <after jump addr> <succeed_n count>
2256 jump_n <succeed_n addr> <jump count>
2257 (The upper bound and `jump_n' are omitted if
2258 `upper_bound' is 1, though.) */
2260 { /* If the upper bound is > 1, we need to insert
2261 more at the end of the loop. */
2262 unsigned nbytes
= 10 + (upper_bound
> 1) * 10;
2264 GET_BUFFER_SPACE (nbytes
);
2266 /* Initialize lower bound of the `succeed_n', even
2267 though it will be set during matching by its
2268 attendant `set_number_at' (inserted next),
2269 because `re_compile_fastmap' needs to know.
2270 Jump to the `jump_n' we might insert below. */
2271 INSERT_JUMP2 (succeed_n
, laststart
,
2272 b
+ 5 + (upper_bound
> 1) * 5,
2276 /* Code to initialize the lower bound. Insert
2277 before the `succeed_n'. The `5' is the last two
2278 bytes of this `set_number_at', plus 3 bytes of
2279 the following `succeed_n'. */
2280 insert_op2 (set_number_at
, laststart
, 5, lower_bound
, b
);
2283 if (upper_bound
> 1)
2284 { /* More than one repetition is allowed, so
2285 append a backward jump to the `succeed_n'
2286 that starts this interval.
2288 When we've reached this during matching,
2289 we'll have matched the interval once, so
2290 jump back only `upper_bound - 1' times. */
2291 STORE_JUMP2 (jump_n
, b
, laststart
+ 5,
2295 /* The location we want to set is the second
2296 parameter of the `jump_n'; that is `b-2' as
2297 an absolute address. `laststart' will be
2298 the `set_number_at' we're about to insert;
2299 `laststart+3' the number to set, the source
2300 for the relative address. But we are
2301 inserting into the middle of the pattern --
2302 so everything is getting moved up by 5.
2303 Conclusion: (b - 2) - (laststart + 3) + 5,
2304 i.e., b - laststart.
2306 We insert this at the beginning of the loop
2307 so that if we fail during matching, we'll
2308 reinitialize the bounds. */
2309 insert_op2 (set_number_at
, laststart
, b
- laststart
,
2310 upper_bound
- 1, b
);
2315 beg_interval
= NULL
;
2320 /* If an invalid interval, match the characters as literals. */
2321 assert (beg_interval
);
2323 beg_interval
= NULL
;
2325 /* normal_char and normal_backslash need `c'. */
2328 if (!(syntax
& RE_NO_BK_BRACES
))
2330 if (p
> pattern
&& p
[-1] == '\\')
2331 goto normal_backslash
;
2336 /* There is no way to specify the before_dot and after_dot
2337 operators. rms says this is ok. --karl */
2345 BUF_PUSH_2 (syntaxspec
, syntax_spec_code
[c
]);
2351 BUF_PUSH_2 (notsyntaxspec
, syntax_spec_code
[c
]);
2358 BUF_PUSH (wordchar
);
2364 BUF_PUSH (notwordchar
);
2377 BUF_PUSH (wordbound
);
2381 BUF_PUSH (notwordbound
);
2392 case '1': case '2': case '3': case '4': case '5':
2393 case '6': case '7': case '8': case '9':
2394 if (syntax
& RE_NO_BK_REFS
)
2402 /* Can't back reference to a subexpression if inside of it. */
2403 if (group_in_compile_stack (compile_stack
, c1
))
2407 BUF_PUSH_2 (duplicate
, c1
);
2413 if (syntax
& RE_BK_PLUS_QM
)
2416 goto normal_backslash
;
2420 /* You might think it would be useful for \ to mean
2421 not to translate; but if we don't translate it
2422 it will never match anything. */
2430 /* Expects the character in `c'. */
2432 /* If no exactn currently being built. */
2435 /* If last exactn not at current position. */
2436 || pending_exact
+ *pending_exact
+ 1 != b
2438 /* We have only one byte following the exactn for the count. */
2439 || *pending_exact
== (1 << BYTEWIDTH
) - 1
2441 /* If followed by a repetition operator. */
2442 || *p
== '*' || *p
== '^'
2443 || ((syntax
& RE_BK_PLUS_QM
)
2444 ? *p
== '\\' && (p
[1] == '+' || p
[1] == '?')
2445 : (*p
== '+' || *p
== '?'))
2446 || ((syntax
& RE_INTERVALS
)
2447 && ((syntax
& RE_NO_BK_BRACES
)
2449 : (p
[0] == '\\' && p
[1] == '{'))))
2451 /* Start building a new exactn. */
2455 BUF_PUSH_2 (exactn
, 0);
2456 pending_exact
= b
- 1;
2463 } /* while p != pend */
2466 /* Through the pattern now. */
2469 STORE_JUMP (jump_past_alt
, fixup_alt_jump
, b
);
2471 if (!COMPILE_STACK_EMPTY
)
2474 free (compile_stack
.stack
);
2476 /* We have succeeded; set the length of the buffer. */
2477 bufp
->used
= b
- bufp
->buffer
;
2482 DEBUG_PRINT1 ("\nCompiled pattern: \n");
2483 print_compiled_pattern (bufp
);
2487 #ifndef MATCH_MAY_ALLOCATE
2488 /* Initialize the failure stack to the largest possible stack. This
2489 isn't necessary unless we're trying to avoid calling alloca in
2490 the search and match routines. */
2492 int num_regs
= bufp
->re_nsub
+ 1;
2494 /* Since DOUBLE_FAIL_STACK refuses to double only if the current size
2495 is strictly greater than re_max_failures, the largest possible stack
2496 is 2 * re_max_failures failure points. */
2497 if (fail_stack
.size
< (2 * re_max_failures
* MAX_FAILURE_ITEMS
))
2499 fail_stack
.size
= (2 * re_max_failures
* MAX_FAILURE_ITEMS
);
2502 if (! fail_stack
.stack
)
2504 = (fail_stack_elt_t
*) xmalloc (fail_stack
.size
2505 * sizeof (fail_stack_elt_t
));
2508 = (fail_stack_elt_t
*) xrealloc (fail_stack
.stack
,
2510 * sizeof (fail_stack_elt_t
)));
2511 #else /* not emacs */
2512 if (! fail_stack
.stack
)
2514 = (fail_stack_elt_t
*) malloc (fail_stack
.size
2515 * sizeof (fail_stack_elt_t
));
2518 = (fail_stack_elt_t
*) realloc (fail_stack
.stack
,
2520 * sizeof (fail_stack_elt_t
)));
2521 #endif /* not emacs */
2524 /* Initialize some other variables the matcher uses. */
2525 RETALLOC_IF (regstart
, num_regs
, const char *);
2526 RETALLOC_IF (regend
, num_regs
, const char *);
2527 RETALLOC_IF (old_regstart
, num_regs
, const char *);
2528 RETALLOC_IF (old_regend
, num_regs
, const char *);
2529 RETALLOC_IF (best_regstart
, num_regs
, const char *);
2530 RETALLOC_IF (best_regend
, num_regs
, const char *);
2531 RETALLOC_IF (reg_info
, num_regs
, register_info_type
);
2532 RETALLOC_IF (reg_dummy
, num_regs
, const char *);
2533 RETALLOC_IF (reg_info_dummy
, num_regs
, register_info_type
);
2538 } /* regex_compile */
2540 /* Subroutines for `regex_compile'. */
2542 /* Store OP at LOC followed by two-byte integer parameter ARG. */
2545 store_op1 (op
, loc
, arg
)
2550 *loc
= (unsigned char) op
;
2551 STORE_NUMBER (loc
+ 1, arg
);
2555 /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
2558 store_op2 (op
, loc
, arg1
, arg2
)
2563 *loc
= (unsigned char) op
;
2564 STORE_NUMBER (loc
+ 1, arg1
);
2565 STORE_NUMBER (loc
+ 3, arg2
);
2569 /* Copy the bytes from LOC to END to open up three bytes of space at LOC
2570 for OP followed by two-byte integer parameter ARG. */
2573 insert_op1 (op
, loc
, arg
, end
)
2579 register unsigned char *pfrom
= end
;
2580 register unsigned char *pto
= end
+ 3;
2582 while (pfrom
!= loc
)
2585 store_op1 (op
, loc
, arg
);
2589 /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
2592 insert_op2 (op
, loc
, arg1
, arg2
, end
)
2598 register unsigned char *pfrom
= end
;
2599 register unsigned char *pto
= end
+ 5;
2601 while (pfrom
!= loc
)
2604 store_op2 (op
, loc
, arg1
, arg2
);
2608 /* P points to just after a ^ in PATTERN. Return true if that ^ comes
2609 after an alternative or a begin-subexpression. We assume there is at
2610 least one character before the ^. */
2613 at_begline_loc_p (pattern
, p
, syntax
)
2614 const char *pattern
, *p
;
2615 reg_syntax_t syntax
;
2617 const char *prev
= p
- 2;
2618 boolean prev_prev_backslash
= prev
> pattern
&& prev
[-1] == '\\';
2621 /* After a subexpression? */
2622 (*prev
== '(' && (syntax
& RE_NO_BK_PARENS
|| prev_prev_backslash
))
2623 /* After an alternative? */
2624 || (*prev
== '|' && (syntax
& RE_NO_BK_VBAR
|| prev_prev_backslash
));
2628 /* The dual of at_begline_loc_p. This one is for $. We assume there is
2629 at least one character after the $, i.e., `P < PEND'. */
2632 at_endline_loc_p (p
, pend
, syntax
)
2633 const char *p
, *pend
;
2636 const char *next
= p
;
2637 boolean next_backslash
= *next
== '\\';
2638 const char *next_next
= p
+ 1 < pend
? p
+ 1 : NULL
;
2641 /* Before a subexpression? */
2642 (syntax
& RE_NO_BK_PARENS
? *next
== ')'
2643 : next_backslash
&& next_next
&& *next_next
== ')')
2644 /* Before an alternative? */
2645 || (syntax
& RE_NO_BK_VBAR
? *next
== '|'
2646 : next_backslash
&& next_next
&& *next_next
== '|');
2650 /* Returns true if REGNUM is in one of COMPILE_STACK's elements and
2651 false if it's not. */
2654 group_in_compile_stack (compile_stack
, regnum
)
2655 compile_stack_type compile_stack
;
2660 for (this_element
= compile_stack
.avail
- 1;
2663 if (compile_stack
.stack
[this_element
].regnum
== regnum
)
2670 /* Read the ending character of a range (in a bracket expression) from the
2671 uncompiled pattern *P_PTR (which ends at PEND). We assume the
2672 starting character is in `P[-2]'. (`P[-1]' is the character `-'.)
2673 Then we set the translation of all bits between the starting and
2674 ending characters (inclusive) in the compiled pattern B.
2676 Return an error code.
2678 We use these short variable names so we can use the same macros as
2679 `regex_compile' itself. */
2681 static reg_errcode_t
2682 compile_range (p_ptr
, pend
, translate
, syntax
, b
)
2683 const char **p_ptr
, *pend
;
2685 reg_syntax_t syntax
;
2690 const char *p
= *p_ptr
;
2691 int range_start
, range_end
;
2696 /* Even though the pattern is a signed `char *', we need to fetch
2697 with unsigned char *'s; if the high bit of the pattern character
2698 is set, the range endpoints will be negative if we fetch using a
2701 We also want to fetch the endpoints without translating them; the
2702 appropriate translation is done in the bit-setting loop below. */
2703 range_start
= ((unsigned char *) p
)[-2];
2704 range_end
= ((unsigned char *) p
)[0];
2706 /* Have to increment the pointer into the pattern string, so the
2707 caller isn't still at the ending character. */
2710 /* If the start is after the end, the range is empty. */
2711 if (range_start
> range_end
)
2712 return syntax
& RE_NO_EMPTY_RANGES
? REG_ERANGE
: REG_NOERROR
;
2714 /* Here we see why `this_char' has to be larger than an `unsigned
2715 char' -- the range is inclusive, so if `range_end' == 0xff
2716 (assuming 8-bit characters), we would otherwise go into an infinite
2717 loop, since all characters <= 0xff. */
2718 for (this_char
= range_start
; this_char
<= range_end
; this_char
++)
2720 SET_LIST_BIT (TRANSLATE (this_char
));
2726 /* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
2727 BUFP. A fastmap records which of the (1 << BYTEWIDTH) possible
2728 characters can start a string that matches the pattern. This fastmap
2729 is used by re_search to skip quickly over impossible starting points.
2731 The caller must supply the address of a (1 << BYTEWIDTH)-byte data
2732 area as BUFP->fastmap.
2734 We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
2737 Returns 0 if we succeed, -2 if an internal error. */
2740 re_compile_fastmap (bufp
)
2741 struct re_pattern_buffer
*bufp
;
2744 #ifdef MATCH_MAY_ALLOCATE
2745 fail_stack_type fail_stack
;
2747 #ifndef REGEX_MALLOC
2750 /* We don't push any register information onto the failure stack. */
2751 unsigned num_regs
= 0;
2753 register char *fastmap
= bufp
->fastmap
;
2754 unsigned char *pattern
= bufp
->buffer
;
2755 unsigned long size
= bufp
->used
;
2756 unsigned char *p
= pattern
;
2757 register unsigned char *pend
= pattern
+ size
;
2759 /* Assume that each path through the pattern can be null until
2760 proven otherwise. We set this false at the bottom of switch
2761 statement, to which we get only if a particular path doesn't
2762 match the empty string. */
2763 boolean path_can_be_null
= true;
2765 /* We aren't doing a `succeed_n' to begin with. */
2766 boolean succeed_n_p
= false;
2768 assert (fastmap
!= NULL
&& p
!= NULL
);
2771 bzero (fastmap
, 1 << BYTEWIDTH
); /* Assume nothing's valid. */
2772 bufp
->fastmap_accurate
= 1; /* It will be when we're done. */
2773 bufp
->can_be_null
= 0;
2775 while (p
!= pend
|| !FAIL_STACK_EMPTY ())
2779 bufp
->can_be_null
|= path_can_be_null
;
2781 /* Reset for next path. */
2782 path_can_be_null
= true;
2784 p
= fail_stack
.stack
[--fail_stack
.avail
];
2787 /* We should never be about to go beyond the end of the pattern. */
2790 #ifdef SWITCH_ENUM_BUG
2791 switch ((int) ((re_opcode_t
) *p
++))
2793 switch ((re_opcode_t
) *p
++)
2797 /* I guess the idea here is to simply not bother with a fastmap
2798 if a backreference is used, since it's too hard to figure out
2799 the fastmap for the corresponding group. Setting
2800 `can_be_null' stops `re_search_2' from using the fastmap, so
2801 that is all we do. */
2803 bufp
->can_be_null
= 1;
2807 /* Following are the cases which match a character. These end
2816 for (j
= *p
++ * BYTEWIDTH
- 1; j
>= 0; j
--)
2817 if (p
[j
/ BYTEWIDTH
] & (1 << (j
% BYTEWIDTH
)))
2823 /* Chars beyond end of map must be allowed. */
2824 for (j
= *p
* BYTEWIDTH
; j
< (1 << BYTEWIDTH
); j
++)
2827 for (j
= *p
++ * BYTEWIDTH
- 1; j
>= 0; j
--)
2828 if (!(p
[j
/ BYTEWIDTH
] & (1 << (j
% BYTEWIDTH
))))
2834 for (j
= 0; j
< (1 << BYTEWIDTH
); j
++)
2835 if (SYNTAX (j
) == Sword
)
2841 for (j
= 0; j
< (1 << BYTEWIDTH
); j
++)
2842 if (SYNTAX (j
) != Sword
)
2848 /* `.' matches anything ... */
2849 for (j
= 0; j
< (1 << BYTEWIDTH
); j
++)
2852 /* ... except perhaps newline. */
2853 if (!(bufp
->syntax
& RE_DOT_NEWLINE
))
2856 /* Return if we have already set `can_be_null'; if we have,
2857 then the fastmap is irrelevant. Something's wrong here. */
2858 else if (bufp
->can_be_null
)
2861 /* Otherwise, have to check alternative paths. */
2868 for (j
= 0; j
< (1 << BYTEWIDTH
); j
++)
2869 if (SYNTAX (j
) == (enum syntaxcode
) k
)
2876 for (j
= 0; j
< (1 << BYTEWIDTH
); j
++)
2877 if (SYNTAX (j
) != (enum syntaxcode
) k
)
2882 /* All cases after this match the empty string. These end with
2890 #endif /* not emacs */
2902 case push_dummy_failure
:
2907 case pop_failure_jump
:
2908 case maybe_pop_jump
:
2911 case dummy_failure_jump
:
2912 EXTRACT_NUMBER_AND_INCR (j
, p
);
2917 /* Jump backward implies we just went through the body of a
2918 loop and matched nothing. Opcode jumped to should be
2919 `on_failure_jump' or `succeed_n'. Just treat it like an
2920 ordinary jump. For a * loop, it has pushed its failure
2921 point already; if so, discard that as redundant. */
2922 if ((re_opcode_t
) *p
!= on_failure_jump
2923 && (re_opcode_t
) *p
!= succeed_n
)
2927 EXTRACT_NUMBER_AND_INCR (j
, p
);
2930 /* If what's on the stack is where we are now, pop it. */
2931 if (!FAIL_STACK_EMPTY ()
2932 && fail_stack
.stack
[fail_stack
.avail
- 1] == p
)
2938 case on_failure_jump
:
2939 case on_failure_keep_string_jump
:
2940 handle_on_failure_jump
:
2941 EXTRACT_NUMBER_AND_INCR (j
, p
);
2943 /* For some patterns, e.g., `(a?)?', `p+j' here points to the
2944 end of the pattern. We don't want to push such a point,
2945 since when we restore it above, entering the switch will
2946 increment `p' past the end of the pattern. We don't need
2947 to push such a point since we obviously won't find any more
2948 fastmap entries beyond `pend'. Such a pattern can match
2949 the null string, though. */
2952 if (!PUSH_PATTERN_OP (p
+ j
, fail_stack
))
2956 bufp
->can_be_null
= 1;
2960 EXTRACT_NUMBER_AND_INCR (k
, p
); /* Skip the n. */
2961 succeed_n_p
= false;
2968 /* Get to the number of times to succeed. */
2971 /* Increment p past the n for when k != 0. */
2972 EXTRACT_NUMBER_AND_INCR (k
, p
);
2976 succeed_n_p
= true; /* Spaghetti code alert. */
2977 goto handle_on_failure_jump
;
2994 abort (); /* We have listed all the cases. */
2997 /* Getting here means we have found the possible starting
2998 characters for one path of the pattern -- and that the empty
2999 string does not match. We need not follow this path further.
3000 Instead, look at the next alternative (remembered on the
3001 stack), or quit if no more. The test at the top of the loop
3002 does these things. */
3003 path_can_be_null
= false;
3007 /* Set `can_be_null' for the last path (also the first path, if the
3008 pattern is empty). */
3009 bufp
->can_be_null
|= path_can_be_null
;
3011 } /* re_compile_fastmap */
3013 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
3014 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
3015 this memory for recording register information. STARTS and ENDS
3016 must be allocated using the malloc library routine, and must each
3017 be at least NUM_REGS * sizeof (regoff_t) bytes long.
3019 If NUM_REGS == 0, then subsequent matches should allocate their own
3022 Unless this function is called, the first search or match using
3023 PATTERN_BUFFER will allocate its own register data, without
3024 freeing the old data. */
3027 re_set_registers (bufp
, regs
, num_regs
, starts
, ends
)
3028 struct re_pattern_buffer
*bufp
;
3029 struct re_registers
*regs
;
3031 regoff_t
*starts
, *ends
;
3035 bufp
->regs_allocated
= REGS_REALLOCATE
;
3036 regs
->num_regs
= num_regs
;
3037 regs
->start
= starts
;
3042 bufp
->regs_allocated
= REGS_UNALLOCATED
;
3044 regs
->start
= regs
->end
= (regoff_t
*) 0;
3048 /* Searching routines. */
3050 /* Like re_search_2, below, but only one string is specified, and
3051 doesn't let you say where to stop matching. */
3054 re_search (bufp
, string
, size
, startpos
, range
, regs
)
3055 struct re_pattern_buffer
*bufp
;
3057 int size
, startpos
, range
;
3058 struct re_registers
*regs
;
3060 return re_search_2 (bufp
, NULL
, 0, string
, size
, startpos
, range
,
3065 /* Using the compiled pattern in BUFP->buffer, first tries to match the
3066 virtual concatenation of STRING1 and STRING2, starting first at index
3067 STARTPOS, then at STARTPOS + 1, and so on.
3069 STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
3071 RANGE is how far to scan while trying to match. RANGE = 0 means try
3072 only at STARTPOS; in general, the last start tried is STARTPOS +
3075 In REGS, return the indices of the virtual concatenation of STRING1
3076 and STRING2 that matched the entire BUFP->buffer and its contained
3079 Do not consider matching one past the index STOP in the virtual
3080 concatenation of STRING1 and STRING2.
3082 We return either the position in the strings at which the match was
3083 found, -1 if no match, or -2 if error (such as failure
3087 re_search_2 (bufp
, string1
, size1
, string2
, size2
, startpos
, range
, regs
, stop
)
3088 struct re_pattern_buffer
*bufp
;
3089 const char *string1
, *string2
;
3093 struct re_registers
*regs
;
3097 register char *fastmap
= bufp
->fastmap
;
3098 register char *translate
= bufp
->translate
;
3099 int total_size
= size1
+ size2
;
3100 int endpos
= startpos
+ range
;
3102 /* Check for out-of-range STARTPOS. */
3103 if (startpos
< 0 || startpos
> total_size
)
3106 /* Fix up RANGE if it might eventually take us outside
3107 the virtual concatenation of STRING1 and STRING2. */
3109 range
= -1 - startpos
;
3110 else if (endpos
> total_size
)
3111 range
= total_size
- startpos
;
3113 /* If the search isn't to be a backwards one, don't waste time in a
3114 search for a pattern that must be anchored. */
3115 if (bufp
->used
> 0 && (re_opcode_t
) bufp
->buffer
[0] == begbuf
&& range
> 0)
3123 /* Update the fastmap now if not correct already. */
3124 if (fastmap
&& !bufp
->fastmap_accurate
)
3125 if (re_compile_fastmap (bufp
) == -2)
3128 /* Loop through the string, looking for a place to start matching. */
3131 /* If a fastmap is supplied, skip quickly over characters that
3132 cannot be the start of a match. If the pattern can match the
3133 null string, however, we don't need to skip characters; we want
3134 the first null string. */
3135 if (fastmap
&& startpos
< total_size
&& !bufp
->can_be_null
)
3137 if (range
> 0) /* Searching forwards. */
3139 register const char *d
;
3140 register int lim
= 0;
3143 if (startpos
< size1
&& startpos
+ range
>= size1
)
3144 lim
= range
- (size1
- startpos
);
3146 d
= (startpos
>= size1
? string2
- size1
: string1
) + startpos
;
3148 /* Written out as an if-else to avoid testing `translate'
3152 && !fastmap
[(unsigned char)
3153 translate
[(unsigned char) *d
++]])
3156 while (range
> lim
&& !fastmap
[(unsigned char) *d
++])
3159 startpos
+= irange
- range
;
3161 else /* Searching backwards. */
3163 register char c
= (size1
== 0 || startpos
>= size1
3164 ? string2
[startpos
- size1
]
3165 : string1
[startpos
]);
3167 if (!fastmap
[(unsigned char) TRANSLATE (c
)])
3172 /* If can't match the null string, and that's all we have left, fail. */
3173 if (range
>= 0 && startpos
== total_size
&& fastmap
3174 && !bufp
->can_be_null
)
3177 val
= re_match_2_internal (bufp
, string1
, size1
, string2
, size2
,
3178 startpos
, regs
, stop
);
3204 /* Declarations and macros for re_match_2. */
3206 static int bcmp_translate ();
3207 static boolean
alt_match_null_string_p (),
3208 common_op_match_null_string_p (),
3209 group_match_null_string_p ();
3211 /* This converts PTR, a pointer into one of the search strings `string1'
3212 and `string2' into an offset from the beginning of that string. */
3213 #define POINTER_TO_OFFSET(ptr) \
3214 (FIRST_STRING_P (ptr) \
3215 ? ((regoff_t) ((ptr) - string1)) \
3216 : ((regoff_t) ((ptr) - string2 + size1)))
3218 /* Macros for dealing with the split strings in re_match_2. */
3220 #define MATCHING_IN_FIRST_STRING (dend == end_match_1)
3222 /* Call before fetching a character with *d. This switches over to
3223 string2 if necessary. */
3224 #define PREFETCH() \
3227 /* End of string2 => fail. */ \
3228 if (dend == end_match_2) \
3230 /* End of string1 => advance to string2. */ \
3232 dend = end_match_2; \
3236 /* Test if at very beginning or at very end of the virtual concatenation
3237 of `string1' and `string2'. If only one string, it's `string2'. */
3238 #define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
3239 #define AT_STRINGS_END(d) ((d) == end2)
3242 /* Test if D points to a character which is word-constituent. We have
3243 two special cases to check for: if past the end of string1, look at
3244 the first character in string2; and if before the beginning of
3245 string2, look at the last character in string1. */
3246 #define WORDCHAR_P(d) \
3247 (SYNTAX ((d) == end1 ? *string2 \
3248 : (d) == string2 - 1 ? *(end1 - 1) : *(d)) \
3251 /* Test if the character before D and the one at D differ with respect
3252 to being word-constituent. */
3253 #define AT_WORD_BOUNDARY(d) \
3254 (AT_STRINGS_BEG (d) || AT_STRINGS_END (d) \
3255 || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
3258 /* Free everything we malloc. */
3259 #ifdef MATCH_MAY_ALLOCATE
3261 #define FREE_VAR(var) if (var) free (var); var = NULL
3262 #define FREE_VARIABLES() \
3264 FREE_VAR (fail_stack.stack); \
3265 FREE_VAR (regstart); \
3266 FREE_VAR (regend); \
3267 FREE_VAR (old_regstart); \
3268 FREE_VAR (old_regend); \
3269 FREE_VAR (best_regstart); \
3270 FREE_VAR (best_regend); \
3271 FREE_VAR (reg_info); \
3272 FREE_VAR (reg_dummy); \
3273 FREE_VAR (reg_info_dummy); \
3275 #else /* not REGEX_MALLOC */
3276 /* This used to do alloca (0), but now we do that in the caller. */
3277 #define FREE_VARIABLES() /* Nothing */
3278 #endif /* not REGEX_MALLOC */
3280 #define FREE_VARIABLES() /* Do nothing! */
3281 #endif /* not MATCH_MAY_ALLOCATE */
3283 /* These values must meet several constraints. They must not be valid
3284 register values; since we have a limit of 255 registers (because
3285 we use only one byte in the pattern for the register number), we can
3286 use numbers larger than 255. They must differ by 1, because of
3287 NUM_FAILURE_ITEMS above. And the value for the lowest register must
3288 be larger than the value for the highest register, so we do not try
3289 to actually save any registers when none are active. */
3290 #define NO_HIGHEST_ACTIVE_REG (1 << BYTEWIDTH)
3291 #define NO_LOWEST_ACTIVE_REG (NO_HIGHEST_ACTIVE_REG + 1)
3293 /* Matching routines. */
3295 #ifndef emacs /* Emacs never uses this. */
3296 /* re_match is like re_match_2 except it takes only a single string. */
3299 re_match (bufp
, string
, size
, pos
, regs
)
3300 struct re_pattern_buffer
*bufp
;
3303 struct re_registers
*regs
;
3305 int result
= re_match_2_internal (bufp
, NULL
, 0, string
, size
,
3310 #endif /* not emacs */
3313 /* re_match_2 matches the compiled pattern in BUFP against the
3314 the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
3315 and SIZE2, respectively). We start matching at POS, and stop
3318 If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
3319 store offsets for the substring each group matched in REGS. See the
3320 documentation for exactly how many groups we fill.
3322 We return -1 if no match, -2 if an internal error (such as the
3323 failure stack overflowing). Otherwise, we return the length of the
3324 matched substring. */
3327 re_match_2 (bufp
, string1
, size1
, string2
, size2
, pos
, regs
, stop
)
3328 struct re_pattern_buffer
*bufp
;
3329 const char *string1
, *string2
;
3332 struct re_registers
*regs
;
3335 int result
= re_match_2_internal (bufp
, string1
, size1
, string2
, size2
,
3341 /* This is a separate function so that we can force an alloca cleanup
3344 re_match_2_internal (bufp
, string1
, size1
, string2
, size2
, pos
, regs
, stop
)
3345 struct re_pattern_buffer
*bufp
;
3346 const char *string1
, *string2
;
3349 struct re_registers
*regs
;
3352 /* General temporaries. */
3356 /* Just past the end of the corresponding string. */
3357 const char *end1
, *end2
;
3359 /* Pointers into string1 and string2, just past the last characters in
3360 each to consider matching. */
3361 const char *end_match_1
, *end_match_2
;
3363 /* Where we are in the data, and the end of the current string. */
3364 const char *d
, *dend
;
3366 /* Where we are in the pattern, and the end of the pattern. */
3367 unsigned char *p
= bufp
->buffer
;
3368 register unsigned char *pend
= p
+ bufp
->used
;
3370 /* Mark the opcode just after a start_memory, so we can test for an
3371 empty subpattern when we get to the stop_memory. */
3372 unsigned char *just_past_start_mem
= 0;
3374 /* We use this to map every character in the string. */
3375 char *translate
= bufp
->translate
;
3377 /* Failure point stack. Each place that can handle a failure further
3378 down the line pushes a failure point on this stack. It consists of
3379 restart, regend, and reg_info for all registers corresponding to
3380 the subexpressions we're currently inside, plus the number of such
3381 registers, and, finally, two char *'s. The first char * is where
3382 to resume scanning the pattern; the second one is where to resume
3383 scanning the strings. If the latter is zero, the failure point is
3384 a ``dummy''; if a failure happens and the failure point is a dummy,
3385 it gets discarded and the next next one is tried. */
3386 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
3387 fail_stack_type fail_stack
;
3390 static unsigned failure_id
= 0;
3391 unsigned nfailure_points_pushed
= 0, nfailure_points_popped
= 0;
3394 /* We fill all the registers internally, independent of what we
3395 return, for use in backreferences. The number here includes
3396 an element for register zero. */
3397 unsigned num_regs
= bufp
->re_nsub
+ 1;
3399 /* The currently active registers. */
3400 unsigned lowest_active_reg
= NO_LOWEST_ACTIVE_REG
;
3401 unsigned highest_active_reg
= NO_HIGHEST_ACTIVE_REG
;
3403 /* Information on the contents of registers. These are pointers into
3404 the input strings; they record just what was matched (on this
3405 attempt) by a subexpression part of the pattern, that is, the
3406 regnum-th regstart pointer points to where in the pattern we began
3407 matching and the regnum-th regend points to right after where we
3408 stopped matching the regnum-th subexpression. (The zeroth register
3409 keeps track of what the whole pattern matches.) */
3410 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3411 const char **regstart
, **regend
;
3414 /* If a group that's operated upon by a repetition operator fails to
3415 match anything, then the register for its start will need to be
3416 restored because it will have been set to wherever in the string we
3417 are when we last see its open-group operator. Similarly for a
3419 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3420 const char **old_regstart
, **old_regend
;
3423 /* The is_active field of reg_info helps us keep track of which (possibly
3424 nested) subexpressions we are currently in. The matched_something
3425 field of reg_info[reg_num] helps us tell whether or not we have
3426 matched any of the pattern so far this time through the reg_num-th
3427 subexpression. These two fields get reset each time through any
3428 loop their register is in. */
3429 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
3430 register_info_type
*reg_info
;
3433 /* The following record the register info as found in the above
3434 variables when we find a match better than any we've seen before.
3435 This happens as we backtrack through the failure points, which in
3436 turn happens only if we have not yet matched the entire string. */
3437 unsigned best_regs_set
= false;
3438 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3439 const char **best_regstart
, **best_regend
;
3442 /* Logically, this is `best_regend[0]'. But we don't want to have to
3443 allocate space for that if we're not allocating space for anything
3444 else (see below). Also, we never need info about register 0 for
3445 any of the other register vectors, and it seems rather a kludge to
3446 treat `best_regend' differently than the rest. So we keep track of
3447 the end of the best match so far in a separate variable. We
3448 initialize this to NULL so that when we backtrack the first time
3449 and need to test it, it's not garbage. */
3450 const char *match_end
= NULL
;
3452 /* Used when we pop values we don't care about. */
3453 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3454 const char **reg_dummy
;
3455 register_info_type
*reg_info_dummy
;
3459 /* Counts the total number of registers pushed. */
3460 unsigned num_regs_pushed
= 0;
3463 DEBUG_PRINT1 ("\n\nEntering re_match_2.\n");
3467 #ifdef MATCH_MAY_ALLOCATE
3468 /* Do not bother to initialize all the register variables if there are
3469 no groups in the pattern, as it takes a fair amount of time. If
3470 there are groups, we include space for register 0 (the whole
3471 pattern), even though we never use it, since it simplifies the
3472 array indexing. We should fix this. */
3475 regstart
= REGEX_TALLOC (num_regs
, const char *);
3476 regend
= REGEX_TALLOC (num_regs
, const char *);
3477 old_regstart
= REGEX_TALLOC (num_regs
, const char *);
3478 old_regend
= REGEX_TALLOC (num_regs
, const char *);
3479 best_regstart
= REGEX_TALLOC (num_regs
, const char *);
3480 best_regend
= REGEX_TALLOC (num_regs
, const char *);
3481 reg_info
= REGEX_TALLOC (num_regs
, register_info_type
);
3482 reg_dummy
= REGEX_TALLOC (num_regs
, const char *);
3483 reg_info_dummy
= REGEX_TALLOC (num_regs
, register_info_type
);
3485 if (!(regstart
&& regend
&& old_regstart
&& old_regend
&& reg_info
3486 && best_regstart
&& best_regend
&& reg_dummy
&& reg_info_dummy
))
3492 #if defined (REGEX_MALLOC)
3495 /* We must initialize all our variables to NULL, so that
3496 `FREE_VARIABLES' doesn't try to free them. */
3497 regstart
= regend
= old_regstart
= old_regend
= best_regstart
3498 = best_regend
= reg_dummy
= NULL
;
3499 reg_info
= reg_info_dummy
= (register_info_type
*) NULL
;
3501 #endif /* REGEX_MALLOC */
3502 #endif /* MATCH_MAY_ALLOCATE */
3504 /* The starting position is bogus. */
3505 if (pos
< 0 || pos
> size1
+ size2
)
3511 /* Initialize subexpression text positions to -1 to mark ones that no
3512 start_memory/stop_memory has been seen for. Also initialize the
3513 register information struct. */
3514 for (mcnt
= 1; mcnt
< num_regs
; mcnt
++)
3516 regstart
[mcnt
] = regend
[mcnt
]
3517 = old_regstart
[mcnt
] = old_regend
[mcnt
] = REG_UNSET_VALUE
;
3519 REG_MATCH_NULL_STRING_P (reg_info
[mcnt
]) = MATCH_NULL_UNSET_VALUE
;
3520 IS_ACTIVE (reg_info
[mcnt
]) = 0;
3521 MATCHED_SOMETHING (reg_info
[mcnt
]) = 0;
3522 EVER_MATCHED_SOMETHING (reg_info
[mcnt
]) = 0;
3525 /* We move `string1' into `string2' if the latter's empty -- but not if
3526 `string1' is null. */
3527 if (size2
== 0 && string1
!= NULL
)
3534 end1
= string1
+ size1
;
3535 end2
= string2
+ size2
;
3537 /* Compute where to stop matching, within the two strings. */
3540 end_match_1
= string1
+ stop
;
3541 end_match_2
= string2
;
3546 end_match_2
= string2
+ stop
- size1
;
3549 /* `p' scans through the pattern as `d' scans through the data.
3550 `dend' is the end of the input string that `d' points within. `d'
3551 is advanced into the following input string whenever necessary, but
3552 this happens before fetching; therefore, at the beginning of the
3553 loop, `d' can be pointing at the end of a string, but it cannot
3555 if (size1
> 0 && pos
<= size1
)
3562 d
= string2
+ pos
- size1
;
3566 DEBUG_PRINT1 ("The compiled pattern is: ");
3567 DEBUG_PRINT_COMPILED_PATTERN (bufp
, p
, pend
);
3568 DEBUG_PRINT1 ("The string to match is: `");
3569 DEBUG_PRINT_DOUBLE_STRING (d
, string1
, size1
, string2
, size2
);
3570 DEBUG_PRINT1 ("'\n");
3572 /* This loops over pattern commands. It exits by returning from the
3573 function if the match is complete, or it drops through if the match
3574 fails at this starting point in the input data. */
3577 DEBUG_PRINT2 ("\n0x%x: ", p
);
3580 { /* End of pattern means we might have succeeded. */
3581 DEBUG_PRINT1 ("end of pattern ... ");
3583 /* If we haven't matched the entire string, and we want the
3584 longest match, try backtracking. */
3585 if (d
!= end_match_2
)
3587 DEBUG_PRINT1 ("backtracking.\n");
3589 if (!FAIL_STACK_EMPTY ())
3590 { /* More failure points to try. */
3591 boolean same_str_p
= (FIRST_STRING_P (match_end
)
3592 == MATCHING_IN_FIRST_STRING
);
3594 /* If exceeds best match so far, save it. */
3596 || (same_str_p
&& d
> match_end
)
3597 || (!same_str_p
&& !MATCHING_IN_FIRST_STRING
))
3599 best_regs_set
= true;
3602 DEBUG_PRINT1 ("\nSAVING match as best so far.\n");
3604 for (mcnt
= 1; mcnt
< num_regs
; mcnt
++)
3606 best_regstart
[mcnt
] = regstart
[mcnt
];
3607 best_regend
[mcnt
] = regend
[mcnt
];
3613 /* If no failure points, don't restore garbage. */
3614 else if (best_regs_set
)
3617 /* Restore best match. It may happen that `dend ==
3618 end_match_1' while the restored d is in string2.
3619 For example, the pattern `x.*y.*z' against the
3620 strings `x-' and `y-z-', if the two strings are
3621 not consecutive in memory. */
3622 DEBUG_PRINT1 ("Restoring best registers.\n");
3625 dend
= ((d
>= string1
&& d
<= end1
)
3626 ? end_match_1
: end_match_2
);
3628 for (mcnt
= 1; mcnt
< num_regs
; mcnt
++)
3630 regstart
[mcnt
] = best_regstart
[mcnt
];
3631 regend
[mcnt
] = best_regend
[mcnt
];
3634 } /* d != end_match_2 */
3636 DEBUG_PRINT1 ("Accepting match.\n");
3638 /* If caller wants register contents data back, do it. */
3639 if (regs
&& !bufp
->no_sub
)
3641 /* Have the register data arrays been allocated? */
3642 if (bufp
->regs_allocated
== REGS_UNALLOCATED
)
3643 { /* No. So allocate them with malloc. We need one
3644 extra element beyond `num_regs' for the `-1' marker
3646 regs
->num_regs
= MAX (RE_NREGS
, num_regs
+ 1);
3647 regs
->start
= TALLOC (regs
->num_regs
, regoff_t
);
3648 regs
->end
= TALLOC (regs
->num_regs
, regoff_t
);
3649 if (regs
->start
== NULL
|| regs
->end
== NULL
)
3651 bufp
->regs_allocated
= REGS_REALLOCATE
;
3653 else if (bufp
->regs_allocated
== REGS_REALLOCATE
)
3654 { /* Yes. If we need more elements than were already
3655 allocated, reallocate them. If we need fewer, just
3657 if (regs
->num_regs
< num_regs
+ 1)
3659 regs
->num_regs
= num_regs
+ 1;
3660 RETALLOC (regs
->start
, regs
->num_regs
, regoff_t
);
3661 RETALLOC (regs
->end
, regs
->num_regs
, regoff_t
);
3662 if (regs
->start
== NULL
|| regs
->end
== NULL
)
3668 /* These braces fend off a "empty body in an else-statement"
3669 warning under GCC when assert expands to nothing. */
3670 assert (bufp
->regs_allocated
== REGS_FIXED
);
3673 /* Convert the pointer data in `regstart' and `regend' to
3674 indices. Register zero has to be set differently,
3675 since we haven't kept track of any info for it. */
3676 if (regs
->num_regs
> 0)
3678 regs
->start
[0] = pos
;
3679 regs
->end
[0] = (MATCHING_IN_FIRST_STRING
3680 ? ((regoff_t
) (d
- string1
))
3681 : ((regoff_t
) (d
- string2
+ size1
)));
3684 /* Go through the first `min (num_regs, regs->num_regs)'
3685 registers, since that is all we initialized. */
3686 for (mcnt
= 1; mcnt
< MIN (num_regs
, regs
->num_regs
); mcnt
++)
3688 if (REG_UNSET (regstart
[mcnt
]) || REG_UNSET (regend
[mcnt
]))
3689 regs
->start
[mcnt
] = regs
->end
[mcnt
] = -1;
3693 = (regoff_t
) POINTER_TO_OFFSET (regstart
[mcnt
]);
3695 = (regoff_t
) POINTER_TO_OFFSET (regend
[mcnt
]);
3699 /* If the regs structure we return has more elements than
3700 were in the pattern, set the extra elements to -1. If
3701 we (re)allocated the registers, this is the case,
3702 because we always allocate enough to have at least one
3704 for (mcnt
= num_regs
; mcnt
< regs
->num_regs
; mcnt
++)
3705 regs
->start
[mcnt
] = regs
->end
[mcnt
] = -1;
3706 } /* regs && !bufp->no_sub */
3709 DEBUG_PRINT4 ("%u failure points pushed, %u popped (%u remain).\n",
3710 nfailure_points_pushed
, nfailure_points_popped
,
3711 nfailure_points_pushed
- nfailure_points_popped
);
3712 DEBUG_PRINT2 ("%u registers pushed.\n", num_regs_pushed
);
3714 mcnt
= d
- pos
- (MATCHING_IN_FIRST_STRING
3718 DEBUG_PRINT2 ("Returning %d from re_match_2.\n", mcnt
);
3723 /* Otherwise match next pattern command. */
3724 #ifdef SWITCH_ENUM_BUG
3725 switch ((int) ((re_opcode_t
) *p
++))
3727 switch ((re_opcode_t
) *p
++)
3730 /* Ignore these. Used to ignore the n of succeed_n's which
3731 currently have n == 0. */
3733 DEBUG_PRINT1 ("EXECUTING no_op.\n");
3737 /* Match the next n pattern characters exactly. The following
3738 byte in the pattern defines n, and the n bytes after that
3739 are the characters to match. */
3742 DEBUG_PRINT2 ("EXECUTING exactn %d.\n", mcnt
);
3744 /* This is written out as an if-else so we don't waste time
3745 testing `translate' inside the loop. */
3751 if (translate
[(unsigned char) *d
++] != (char) *p
++)
3761 if (*d
++ != (char) *p
++) goto fail
;
3765 SET_REGS_MATCHED ();
3769 /* Match any character except possibly a newline or a null. */
3771 DEBUG_PRINT1 ("EXECUTING anychar.\n");
3775 if ((!(bufp
->syntax
& RE_DOT_NEWLINE
) && TRANSLATE (*d
) == '\n')
3776 || (bufp
->syntax
& RE_DOT_NOT_NULL
&& TRANSLATE (*d
) == '\000'))
3779 SET_REGS_MATCHED ();
3780 DEBUG_PRINT2 (" Matched `%d'.\n", *d
);
3788 register unsigned char c
;
3789 boolean
not = (re_opcode_t
) *(p
- 1) == charset_not
;
3791 DEBUG_PRINT2 ("EXECUTING charset%s.\n", not ? "_not" : "");
3794 c
= TRANSLATE (*d
); /* The character to match. */
3796 /* Cast to `unsigned' instead of `unsigned char' in case the
3797 bit list is a full 32 bytes long. */
3798 if (c
< (unsigned) (*p
* BYTEWIDTH
)
3799 && p
[1 + c
/ BYTEWIDTH
] & (1 << (c
% BYTEWIDTH
)))
3804 if (!not) goto fail
;
3806 SET_REGS_MATCHED ();
3812 /* The beginning of a group is represented by start_memory.
3813 The arguments are the register number in the next byte, and the
3814 number of groups inner to this one in the next. The text
3815 matched within the group is recorded (in the internal
3816 registers data structure) under the register number. */
3818 DEBUG_PRINT3 ("EXECUTING start_memory %d (%d):\n", *p
, p
[1]);
3820 /* Find out if this group can match the empty string. */
3821 p1
= p
; /* To send to group_match_null_string_p. */
3823 if (REG_MATCH_NULL_STRING_P (reg_info
[*p
]) == MATCH_NULL_UNSET_VALUE
)
3824 REG_MATCH_NULL_STRING_P (reg_info
[*p
])
3825 = group_match_null_string_p (&p1
, pend
, reg_info
);
3827 /* Save the position in the string where we were the last time
3828 we were at this open-group operator in case the group is
3829 operated upon by a repetition operator, e.g., with `(a*)*b'
3830 against `ab'; then we want to ignore where we are now in
3831 the string in case this attempt to match fails. */
3832 old_regstart
[*p
] = REG_MATCH_NULL_STRING_P (reg_info
[*p
])
3833 ? REG_UNSET (regstart
[*p
]) ? d
: regstart
[*p
]
3835 DEBUG_PRINT2 (" old_regstart: %d\n",
3836 POINTER_TO_OFFSET (old_regstart
[*p
]));
3839 DEBUG_PRINT2 (" regstart: %d\n", POINTER_TO_OFFSET (regstart
[*p
]));
3841 IS_ACTIVE (reg_info
[*p
]) = 1;
3842 MATCHED_SOMETHING (reg_info
[*p
]) = 0;
3844 /* This is the new highest active register. */
3845 highest_active_reg
= *p
;
3847 /* If nothing was active before, this is the new lowest active
3849 if (lowest_active_reg
== NO_LOWEST_ACTIVE_REG
)
3850 lowest_active_reg
= *p
;
3852 /* Move past the register number and inner group count. */
3854 just_past_start_mem
= p
;
3858 /* The stop_memory opcode represents the end of a group. Its
3859 arguments are the same as start_memory's: the register
3860 number, and the number of inner groups. */
3862 DEBUG_PRINT3 ("EXECUTING stop_memory %d (%d):\n", *p
, p
[1]);
3864 /* We need to save the string position the last time we were at
3865 this close-group operator in case the group is operated
3866 upon by a repetition operator, e.g., with `((a*)*(b*)*)*'
3867 against `aba'; then we want to ignore where we are now in
3868 the string in case this attempt to match fails. */
3869 old_regend
[*p
] = REG_MATCH_NULL_STRING_P (reg_info
[*p
])
3870 ? REG_UNSET (regend
[*p
]) ? d
: regend
[*p
]
3872 DEBUG_PRINT2 (" old_regend: %d\n",
3873 POINTER_TO_OFFSET (old_regend
[*p
]));
3876 DEBUG_PRINT2 (" regend: %d\n", POINTER_TO_OFFSET (regend
[*p
]));
3878 /* This register isn't active anymore. */
3879 IS_ACTIVE (reg_info
[*p
]) = 0;
3881 /* If this was the only register active, nothing is active
3883 if (lowest_active_reg
== highest_active_reg
)
3885 lowest_active_reg
= NO_LOWEST_ACTIVE_REG
;
3886 highest_active_reg
= NO_HIGHEST_ACTIVE_REG
;
3889 { /* We must scan for the new highest active register, since
3890 it isn't necessarily one less than now: consider
3891 (a(b)c(d(e)f)g). When group 3 ends, after the f), the
3892 new highest active register is 1. */
3893 unsigned char r
= *p
- 1;
3894 while (r
> 0 && !IS_ACTIVE (reg_info
[r
]))
3897 /* If we end up at register zero, that means that we saved
3898 the registers as the result of an `on_failure_jump', not
3899 a `start_memory', and we jumped to past the innermost
3900 `stop_memory'. For example, in ((.)*) we save
3901 registers 1 and 2 as a result of the *, but when we pop
3902 back to the second ), we are at the stop_memory 1.
3903 Thus, nothing is active. */
3906 lowest_active_reg
= NO_LOWEST_ACTIVE_REG
;
3907 highest_active_reg
= NO_HIGHEST_ACTIVE_REG
;
3910 highest_active_reg
= r
;
3913 /* If just failed to match something this time around with a
3914 group that's operated on by a repetition operator, try to
3915 force exit from the ``loop'', and restore the register
3916 information for this group that we had before trying this
3918 if ((!MATCHED_SOMETHING (reg_info
[*p
])
3919 || just_past_start_mem
== p
- 1)
3922 boolean is_a_jump_n
= false;
3926 switch ((re_opcode_t
) *p1
++)
3930 case pop_failure_jump
:
3931 case maybe_pop_jump
:
3933 case dummy_failure_jump
:
3934 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
3944 /* If the next operation is a jump backwards in the pattern
3945 to an on_failure_jump right before the start_memory
3946 corresponding to this stop_memory, exit from the loop
3947 by forcing a failure after pushing on the stack the
3948 on_failure_jump's jump in the pattern, and d. */
3949 if (mcnt
< 0 && (re_opcode_t
) *p1
== on_failure_jump
3950 && (re_opcode_t
) p1
[3] == start_memory
&& p1
[4] == *p
)
3952 /* If this group ever matched anything, then restore
3953 what its registers were before trying this last
3954 failed match, e.g., with `(a*)*b' against `ab' for
3955 regstart[1], and, e.g., with `((a*)*(b*)*)*'
3956 against `aba' for regend[3].
3958 Also restore the registers for inner groups for,
3959 e.g., `((a*)(b*))*' against `aba' (register 3 would
3960 otherwise get trashed). */
3962 if (EVER_MATCHED_SOMETHING (reg_info
[*p
]))
3966 EVER_MATCHED_SOMETHING (reg_info
[*p
]) = 0;
3968 /* Restore this and inner groups' (if any) registers. */
3969 for (r
= *p
; r
< *p
+ *(p
+ 1); r
++)
3971 regstart
[r
] = old_regstart
[r
];
3973 /* xx why this test? */
3974 if ((int) old_regend
[r
] >= (int) regstart
[r
])
3975 regend
[r
] = old_regend
[r
];
3979 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
3980 PUSH_FAILURE_POINT (p1
+ mcnt
, d
, -2);
3986 /* Move past the register number and the inner group count. */
3991 /* \<digit> has been turned into a `duplicate' command which is
3992 followed by the numeric value of <digit> as the register number. */
3995 register const char *d2
, *dend2
;
3996 int regno
= *p
++; /* Get which register to match against. */
3997 DEBUG_PRINT2 ("EXECUTING duplicate %d.\n", regno
);
3999 /* Can't back reference a group which we've never matched. */
4000 if (REG_UNSET (regstart
[regno
]) || REG_UNSET (regend
[regno
]))
4003 /* Where in input to try to start matching. */
4004 d2
= regstart
[regno
];
4006 /* Where to stop matching; if both the place to start and
4007 the place to stop matching are in the same string, then
4008 set to the place to stop, otherwise, for now have to use
4009 the end of the first string. */
4011 dend2
= ((FIRST_STRING_P (regstart
[regno
])
4012 == FIRST_STRING_P (regend
[regno
]))
4013 ? regend
[regno
] : end_match_1
);
4016 /* If necessary, advance to next segment in register
4020 if (dend2
== end_match_2
) break;
4021 if (dend2
== regend
[regno
]) break;
4023 /* End of string1 => advance to string2. */
4025 dend2
= regend
[regno
];
4027 /* At end of register contents => success */
4028 if (d2
== dend2
) break;
4030 /* If necessary, advance to next segment in data. */
4033 /* How many characters left in this segment to match. */
4036 /* Want how many consecutive characters we can match in
4037 one shot, so, if necessary, adjust the count. */
4038 if (mcnt
> dend2
- d2
)
4041 /* Compare that many; failure if mismatch, else move
4044 ? bcmp_translate (d
, d2
, mcnt
, translate
)
4045 : bcmp (d
, d2
, mcnt
))
4047 d
+= mcnt
, d2
+= mcnt
;
4053 /* begline matches the empty string at the beginning of the string
4054 (unless `not_bol' is set in `bufp'), and, if
4055 `newline_anchor' is set, after newlines. */
4057 DEBUG_PRINT1 ("EXECUTING begline.\n");
4059 if (AT_STRINGS_BEG (d
))
4061 if (!bufp
->not_bol
) break;
4063 else if (d
[-1] == '\n' && bufp
->newline_anchor
)
4067 /* In all other cases, we fail. */
4071 /* endline is the dual of begline. */
4073 DEBUG_PRINT1 ("EXECUTING endline.\n");
4075 if (AT_STRINGS_END (d
))
4077 if (!bufp
->not_eol
) break;
4080 /* We have to ``prefetch'' the next character. */
4081 else if ((d
== end1
? *string2
: *d
) == '\n'
4082 && bufp
->newline_anchor
)
4089 /* Match at the very beginning of the data. */
4091 DEBUG_PRINT1 ("EXECUTING begbuf.\n");
4092 if (AT_STRINGS_BEG (d
))
4097 /* Match at the very end of the data. */
4099 DEBUG_PRINT1 ("EXECUTING endbuf.\n");
4100 if (AT_STRINGS_END (d
))
4105 /* on_failure_keep_string_jump is used to optimize `.*\n'. It
4106 pushes NULL as the value for the string on the stack. Then
4107 `pop_failure_point' will keep the current value for the
4108 string, instead of restoring it. To see why, consider
4109 matching `foo\nbar' against `.*\n'. The .* matches the foo;
4110 then the . fails against the \n. But the next thing we want
4111 to do is match the \n against the \n; if we restored the
4112 string value, we would be back at the foo.
4114 Because this is used only in specific cases, we don't need to
4115 check all the things that `on_failure_jump' does, to make
4116 sure the right things get saved on the stack. Hence we don't
4117 share its code. The only reason to push anything on the
4118 stack at all is that otherwise we would have to change
4119 `anychar's code to do something besides goto fail in this
4120 case; that seems worse than this. */
4121 case on_failure_keep_string_jump
:
4122 DEBUG_PRINT1 ("EXECUTING on_failure_keep_string_jump");
4124 EXTRACT_NUMBER_AND_INCR (mcnt
, p
);
4125 DEBUG_PRINT3 (" %d (to 0x%x):\n", mcnt
, p
+ mcnt
);
4127 PUSH_FAILURE_POINT (p
+ mcnt
, NULL
, -2);
4131 /* Uses of on_failure_jump:
4133 Each alternative starts with an on_failure_jump that points
4134 to the beginning of the next alternative. Each alternative
4135 except the last ends with a jump that in effect jumps past
4136 the rest of the alternatives. (They really jump to the
4137 ending jump of the following alternative, because tensioning
4138 these jumps is a hassle.)
4140 Repeats start with an on_failure_jump that points past both
4141 the repetition text and either the following jump or
4142 pop_failure_jump back to this on_failure_jump. */
4143 case on_failure_jump
:
4145 DEBUG_PRINT1 ("EXECUTING on_failure_jump");
4147 EXTRACT_NUMBER_AND_INCR (mcnt
, p
);
4148 DEBUG_PRINT3 (" %d (to 0x%x)", mcnt
, p
+ mcnt
);
4150 /* If this on_failure_jump comes right before a group (i.e.,
4151 the original * applied to a group), save the information
4152 for that group and all inner ones, so that if we fail back
4153 to this point, the group's information will be correct.
4154 For example, in \(a*\)*\1, we need the preceding group,
4155 and in \(\(a*\)b*\)\2, we need the inner group. */
4157 /* We can't use `p' to check ahead because we push
4158 a failure point to `p + mcnt' after we do this. */
4161 /* We need to skip no_op's before we look for the
4162 start_memory in case this on_failure_jump is happening as
4163 the result of a completed succeed_n, as in \(a\)\{1,3\}b\1
4165 while (p1
< pend
&& (re_opcode_t
) *p1
== no_op
)
4168 if (p1
< pend
&& (re_opcode_t
) *p1
== start_memory
)
4170 /* We have a new highest active register now. This will
4171 get reset at the start_memory we are about to get to,
4172 but we will have saved all the registers relevant to
4173 this repetition op, as described above. */
4174 highest_active_reg
= *(p1
+ 1) + *(p1
+ 2);
4175 if (lowest_active_reg
== NO_LOWEST_ACTIVE_REG
)
4176 lowest_active_reg
= *(p1
+ 1);
4179 DEBUG_PRINT1 (":\n");
4180 PUSH_FAILURE_POINT (p
+ mcnt
, d
, -2);
4184 /* A smart repeat ends with `maybe_pop_jump'.
4185 We change it to either `pop_failure_jump' or `jump'. */
4186 case maybe_pop_jump
:
4187 EXTRACT_NUMBER_AND_INCR (mcnt
, p
);
4188 DEBUG_PRINT2 ("EXECUTING maybe_pop_jump %d.\n", mcnt
);
4190 register unsigned char *p2
= p
;
4192 /* Compare the beginning of the repeat with what in the
4193 pattern follows its end. If we can establish that there
4194 is nothing that they would both match, i.e., that we
4195 would have to backtrack because of (as in, e.g., `a*a')
4196 then we can change to pop_failure_jump, because we'll
4197 never have to backtrack.
4199 This is not true in the case of alternatives: in
4200 `(a|ab)*' we do need to backtrack to the `ab' alternative
4201 (e.g., if the string was `ab'). But instead of trying to
4202 detect that here, the alternative has put on a dummy
4203 failure point which is what we will end up popping. */
4205 /* Skip over open/close-group commands.
4206 If what follows this loop is a ...+ construct,
4207 look at what begins its body, since we will have to
4208 match at least one of that. */
4212 && ((re_opcode_t
) *p2
== stop_memory
4213 || (re_opcode_t
) *p2
== start_memory
))
4215 else if (p2
+ 6 < pend
4216 && (re_opcode_t
) *p2
== dummy_failure_jump
)
4223 /* p1[0] ... p1[2] are the `on_failure_jump' corresponding
4224 to the `maybe_finalize_jump' of this case. Examine what
4227 /* If we're at the end of the pattern, we can change. */
4230 /* Consider what happens when matching ":\(.*\)"
4231 against ":/". I don't really understand this code
4233 p
[-3] = (unsigned char) pop_failure_jump
;
4235 (" End of pattern: change to `pop_failure_jump'.\n");
4238 else if ((re_opcode_t
) *p2
== exactn
4239 || (bufp
->newline_anchor
&& (re_opcode_t
) *p2
== endline
))
4241 register unsigned char c
4242 = *p2
== (unsigned char) endline
? '\n' : p2
[2];
4244 if ((re_opcode_t
) p1
[3] == exactn
&& p1
[5] != c
)
4246 p
[-3] = (unsigned char) pop_failure_jump
;
4247 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n",
4251 else if ((re_opcode_t
) p1
[3] == charset
4252 || (re_opcode_t
) p1
[3] == charset_not
)
4254 int not = (re_opcode_t
) p1
[3] == charset_not
;
4256 if (c
< (unsigned char) (p1
[4] * BYTEWIDTH
)
4257 && p1
[5 + c
/ BYTEWIDTH
] & (1 << (c
% BYTEWIDTH
)))
4260 /* `not' is equal to 1 if c would match, which means
4261 that we can't change to pop_failure_jump. */
4264 p
[-3] = (unsigned char) pop_failure_jump
;
4265 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4269 else if ((re_opcode_t
) *p2
== charset
)
4271 register unsigned char c
4272 = *p2
== (unsigned char) endline
? '\n' : p2
[2];
4274 if ((re_opcode_t
) p1
[3] == exactn
4275 && ! (p2
[1] * BYTEWIDTH
> p1
[4]
4276 && (p2
[1 + p1
[4] / BYTEWIDTH
]
4277 & (1 << (p1
[4] % BYTEWIDTH
)))))
4279 p
[-3] = (unsigned char) pop_failure_jump
;
4280 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n",
4284 else if ((re_opcode_t
) p1
[3] == charset_not
)
4287 /* We win if the charset_not inside the loop
4288 lists every character listed in the charset after. */
4289 for (idx
= 0; idx
< p2
[1]; idx
++)
4290 if (! (p2
[2 + idx
] == 0
4292 && ((p2
[2 + idx
] & ~ p1
[5 + idx
]) == 0))))
4297 p
[-3] = (unsigned char) pop_failure_jump
;
4298 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4301 else if ((re_opcode_t
) p1
[3] == charset
)
4304 /* We win if the charset inside the loop
4305 has no overlap with the one after the loop. */
4306 for (idx
= 0; idx
< p2
[1] && idx
< p1
[4]; idx
++)
4307 if ((p2
[2 + idx
] & p1
[5 + idx
]) != 0)
4310 if (idx
== p2
[1] || idx
== p1
[4])
4312 p
[-3] = (unsigned char) pop_failure_jump
;
4313 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4318 p
-= 2; /* Point at relative address again. */
4319 if ((re_opcode_t
) p
[-1] != pop_failure_jump
)
4321 p
[-1] = (unsigned char) jump
;
4322 DEBUG_PRINT1 (" Match => jump.\n");
4323 goto unconditional_jump
;
4325 /* Note fall through. */
4328 /* The end of a simple repeat has a pop_failure_jump back to
4329 its matching on_failure_jump, where the latter will push a
4330 failure point. The pop_failure_jump takes off failure
4331 points put on by this pop_failure_jump's matching
4332 on_failure_jump; we got through the pattern to here from the
4333 matching on_failure_jump, so didn't fail. */
4334 case pop_failure_jump
:
4336 /* We need to pass separate storage for the lowest and
4337 highest registers, even though we don't care about the
4338 actual values. Otherwise, we will restore only one
4339 register from the stack, since lowest will == highest in
4340 `pop_failure_point'. */
4341 unsigned dummy_low_reg
, dummy_high_reg
;
4342 unsigned char *pdummy
;
4345 DEBUG_PRINT1 ("EXECUTING pop_failure_jump.\n");
4346 POP_FAILURE_POINT (sdummy
, pdummy
,
4347 dummy_low_reg
, dummy_high_reg
,
4348 reg_dummy
, reg_dummy
, reg_info_dummy
);
4350 /* Note fall through. */
4353 /* Unconditionally jump (without popping any failure points). */
4356 EXTRACT_NUMBER_AND_INCR (mcnt
, p
); /* Get the amount to jump. */
4357 DEBUG_PRINT2 ("EXECUTING jump %d ", mcnt
);
4358 p
+= mcnt
; /* Do the jump. */
4359 DEBUG_PRINT2 ("(to 0x%x).\n", p
);
4363 /* We need this opcode so we can detect where alternatives end
4364 in `group_match_null_string_p' et al. */
4366 DEBUG_PRINT1 ("EXECUTING jump_past_alt.\n");
4367 goto unconditional_jump
;
4370 /* Normally, the on_failure_jump pushes a failure point, which
4371 then gets popped at pop_failure_jump. We will end up at
4372 pop_failure_jump, also, and with a pattern of, say, `a+', we
4373 are skipping over the on_failure_jump, so we have to push
4374 something meaningless for pop_failure_jump to pop. */
4375 case dummy_failure_jump
:
4376 DEBUG_PRINT1 ("EXECUTING dummy_failure_jump.\n");
4377 /* It doesn't matter what we push for the string here. What
4378 the code at `fail' tests is the value for the pattern. */
4379 PUSH_FAILURE_POINT (0, 0, -2);
4380 goto unconditional_jump
;
4383 /* At the end of an alternative, we need to push a dummy failure
4384 point in case we are followed by a `pop_failure_jump', because
4385 we don't want the failure point for the alternative to be
4386 popped. For example, matching `(a|ab)*' against `aab'
4387 requires that we match the `ab' alternative. */
4388 case push_dummy_failure
:
4389 DEBUG_PRINT1 ("EXECUTING push_dummy_failure.\n");
4390 /* See comments just above at `dummy_failure_jump' about the
4392 PUSH_FAILURE_POINT (0, 0, -2);
4395 /* Have to succeed matching what follows at least n times.
4396 After that, handle like `on_failure_jump'. */
4398 EXTRACT_NUMBER (mcnt
, p
+ 2);
4399 DEBUG_PRINT2 ("EXECUTING succeed_n %d.\n", mcnt
);
4402 /* Originally, this is how many times we HAVE to succeed. */
4407 STORE_NUMBER_AND_INCR (p
, mcnt
);
4408 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p
, mcnt
);
4412 DEBUG_PRINT2 (" Setting two bytes from 0x%x to no_op.\n", p
+2);
4413 p
[2] = (unsigned char) no_op
;
4414 p
[3] = (unsigned char) no_op
;
4420 EXTRACT_NUMBER (mcnt
, p
+ 2);
4421 DEBUG_PRINT2 ("EXECUTING jump_n %d.\n", mcnt
);
4423 /* Originally, this is how many times we CAN jump. */
4427 STORE_NUMBER (p
+ 2, mcnt
);
4428 goto unconditional_jump
;
4430 /* If don't have to jump any more, skip over the rest of command. */
4437 DEBUG_PRINT1 ("EXECUTING set_number_at.\n");
4439 EXTRACT_NUMBER_AND_INCR (mcnt
, p
);
4441 EXTRACT_NUMBER_AND_INCR (mcnt
, p
);
4442 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p1
, mcnt
);
4443 STORE_NUMBER (p1
, mcnt
);
4448 DEBUG_PRINT1 ("EXECUTING wordbound.\n");
4449 if (AT_WORD_BOUNDARY (d
))
4454 DEBUG_PRINT1 ("EXECUTING notwordbound.\n");
4455 if (AT_WORD_BOUNDARY (d
))
4460 DEBUG_PRINT1 ("EXECUTING wordbeg.\n");
4461 if (WORDCHAR_P (d
) && (AT_STRINGS_BEG (d
) || !WORDCHAR_P (d
- 1)))
4466 DEBUG_PRINT1 ("EXECUTING wordend.\n");
4467 if (!AT_STRINGS_BEG (d
) && WORDCHAR_P (d
- 1)
4468 && (!WORDCHAR_P (d
) || AT_STRINGS_END (d
)))
4474 DEBUG_PRINT1 ("EXECUTING before_dot.\n");
4475 if (PTR_CHAR_POS ((unsigned char *) d
) >= point
)
4480 DEBUG_PRINT1 ("EXECUTING at_dot.\n");
4481 if (PTR_CHAR_POS ((unsigned char *) d
) != point
)
4486 DEBUG_PRINT1 ("EXECUTING after_dot.\n");
4487 if (PTR_CHAR_POS ((unsigned char *) d
) <= point
)
4490 #if 0 /* not emacs19 */
4492 DEBUG_PRINT1 ("EXECUTING at_dot.\n");
4493 if (PTR_CHAR_POS ((unsigned char *) d
) + 1 != point
)
4496 #endif /* not emacs19 */
4499 DEBUG_PRINT2 ("EXECUTING syntaxspec %d.\n", mcnt
);
4504 DEBUG_PRINT1 ("EXECUTING Emacs wordchar.\n");
4508 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
4510 if (SYNTAX (d
[-1]) != (enum syntaxcode
) mcnt
)
4512 SET_REGS_MATCHED ();
4516 DEBUG_PRINT2 ("EXECUTING notsyntaxspec %d.\n", mcnt
);
4518 goto matchnotsyntax
;
4521 DEBUG_PRINT1 ("EXECUTING Emacs notwordchar.\n");
4525 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
4527 if (SYNTAX (d
[-1]) == (enum syntaxcode
) mcnt
)
4529 SET_REGS_MATCHED ();
4532 #else /* not emacs */
4534 DEBUG_PRINT1 ("EXECUTING non-Emacs wordchar.\n");
4536 if (!WORDCHAR_P (d
))
4538 SET_REGS_MATCHED ();
4543 DEBUG_PRINT1 ("EXECUTING non-Emacs notwordchar.\n");
4547 SET_REGS_MATCHED ();
4550 #endif /* not emacs */
4555 continue; /* Successfully executed one pattern command; keep going. */
4558 /* We goto here if a matching operation fails. */
4560 if (!FAIL_STACK_EMPTY ())
4561 { /* A restart point is known. Restore to that state. */
4562 DEBUG_PRINT1 ("\nFAIL:\n");
4563 POP_FAILURE_POINT (d
, p
,
4564 lowest_active_reg
, highest_active_reg
,
4565 regstart
, regend
, reg_info
);
4567 /* If this failure point is a dummy, try the next one. */
4571 /* If we failed to the end of the pattern, don't examine *p. */
4575 boolean is_a_jump_n
= false;
4577 /* If failed to a backwards jump that's part of a repetition
4578 loop, need to pop this failure point and use the next one. */
4579 switch ((re_opcode_t
) *p
)
4583 case maybe_pop_jump
:
4584 case pop_failure_jump
:
4587 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
4590 if ((is_a_jump_n
&& (re_opcode_t
) *p1
== succeed_n
)
4592 && (re_opcode_t
) *p1
== on_failure_jump
))
4600 if (d
>= string1
&& d
<= end1
)
4604 break; /* Matching at this starting point really fails. */
4608 goto restore_best_regs
;
4612 return -1; /* Failure to match. */
4615 /* Subroutine definitions for re_match_2. */
4618 /* We are passed P pointing to a register number after a start_memory.
4620 Return true if the pattern up to the corresponding stop_memory can
4621 match the empty string, and false otherwise.
4623 If we find the matching stop_memory, sets P to point to one past its number.
4624 Otherwise, sets P to an undefined byte less than or equal to END.
4626 We don't handle duplicates properly (yet). */
4629 group_match_null_string_p (p
, end
, reg_info
)
4630 unsigned char **p
, *end
;
4631 register_info_type
*reg_info
;
4634 /* Point to after the args to the start_memory. */
4635 unsigned char *p1
= *p
+ 2;
4639 /* Skip over opcodes that can match nothing, and return true or
4640 false, as appropriate, when we get to one that can't, or to the
4641 matching stop_memory. */
4643 switch ((re_opcode_t
) *p1
)
4645 /* Could be either a loop or a series of alternatives. */
4646 case on_failure_jump
:
4648 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
4650 /* If the next operation is not a jump backwards in the
4655 /* Go through the on_failure_jumps of the alternatives,
4656 seeing if any of the alternatives cannot match nothing.
4657 The last alternative starts with only a jump,
4658 whereas the rest start with on_failure_jump and end
4659 with a jump, e.g., here is the pattern for `a|b|c':
4661 /on_failure_jump/0/6/exactn/1/a/jump_past_alt/0/6
4662 /on_failure_jump/0/6/exactn/1/b/jump_past_alt/0/3
4665 So, we have to first go through the first (n-1)
4666 alternatives and then deal with the last one separately. */
4669 /* Deal with the first (n-1) alternatives, which start
4670 with an on_failure_jump (see above) that jumps to right
4671 past a jump_past_alt. */
4673 while ((re_opcode_t
) p1
[mcnt
-3] == jump_past_alt
)
4675 /* `mcnt' holds how many bytes long the alternative
4676 is, including the ending `jump_past_alt' and
4679 if (!alt_match_null_string_p (p1
, p1
+ mcnt
- 3,
4683 /* Move to right after this alternative, including the
4687 /* Break if it's the beginning of an n-th alternative
4688 that doesn't begin with an on_failure_jump. */
4689 if ((re_opcode_t
) *p1
!= on_failure_jump
)
4692 /* Still have to check that it's not an n-th
4693 alternative that starts with an on_failure_jump. */
4695 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
4696 if ((re_opcode_t
) p1
[mcnt
-3] != jump_past_alt
)
4698 /* Get to the beginning of the n-th alternative. */
4704 /* Deal with the last alternative: go back and get number
4705 of the `jump_past_alt' just before it. `mcnt' contains
4706 the length of the alternative. */
4707 EXTRACT_NUMBER (mcnt
, p1
- 2);
4709 if (!alt_match_null_string_p (p1
, p1
+ mcnt
, reg_info
))
4712 p1
+= mcnt
; /* Get past the n-th alternative. */
4718 assert (p1
[1] == **p
);
4724 if (!common_op_match_null_string_p (&p1
, end
, reg_info
))
4727 } /* while p1 < end */
4730 } /* group_match_null_string_p */
4733 /* Similar to group_match_null_string_p, but doesn't deal with alternatives:
4734 It expects P to be the first byte of a single alternative and END one
4735 byte past the last. The alternative can contain groups. */
4738 alt_match_null_string_p (p
, end
, reg_info
)
4739 unsigned char *p
, *end
;
4740 register_info_type
*reg_info
;
4743 unsigned char *p1
= p
;
4747 /* Skip over opcodes that can match nothing, and break when we get
4748 to one that can't. */
4750 switch ((re_opcode_t
) *p1
)
4753 case on_failure_jump
:
4755 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
4760 if (!common_op_match_null_string_p (&p1
, end
, reg_info
))
4763 } /* while p1 < end */
4766 } /* alt_match_null_string_p */
4769 /* Deals with the ops common to group_match_null_string_p and
4770 alt_match_null_string_p.
4772 Sets P to one after the op and its arguments, if any. */
4775 common_op_match_null_string_p (p
, end
, reg_info
)
4776 unsigned char **p
, *end
;
4777 register_info_type
*reg_info
;
4782 unsigned char *p1
= *p
;
4784 switch ((re_opcode_t
) *p1
++)
4804 assert (reg_no
> 0 && reg_no
<= MAX_REGNUM
);
4805 ret
= group_match_null_string_p (&p1
, end
, reg_info
);
4807 /* Have to set this here in case we're checking a group which
4808 contains a group and a back reference to it. */
4810 if (REG_MATCH_NULL_STRING_P (reg_info
[reg_no
]) == MATCH_NULL_UNSET_VALUE
)
4811 REG_MATCH_NULL_STRING_P (reg_info
[reg_no
]) = ret
;
4817 /* If this is an optimized succeed_n for zero times, make the jump. */
4819 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
4827 /* Get to the number of times to succeed. */
4829 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
4834 EXTRACT_NUMBER_AND_INCR (mcnt
, p1
);
4842 if (!REG_MATCH_NULL_STRING_P (reg_info
[*p1
]))
4850 /* All other opcodes mean we cannot match the empty string. */
4856 } /* common_op_match_null_string_p */
4859 /* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
4860 bytes; nonzero otherwise. */
4863 bcmp_translate (s1
, s2
, len
, translate
)
4864 unsigned char *s1
, *s2
;
4868 register unsigned char *p1
= s1
, *p2
= s2
;
4871 if (translate
[*p1
++] != translate
[*p2
++]) return 1;
4877 /* Entry points for GNU code. */
4879 /* re_compile_pattern is the GNU regular expression compiler: it
4880 compiles PATTERN (of length SIZE) and puts the result in BUFP.
4881 Returns 0 if the pattern was valid, otherwise an error string.
4883 Assumes the `allocated' (and perhaps `buffer') and `translate' fields
4884 are set in BUFP on entry.
4886 We call regex_compile to do the actual compilation. */
4889 re_compile_pattern (pattern
, length
, bufp
)
4890 const char *pattern
;
4892 struct re_pattern_buffer
*bufp
;
4896 /* GNU code is written to assume at least RE_NREGS registers will be set
4897 (and at least one extra will be -1). */
4898 bufp
->regs_allocated
= REGS_UNALLOCATED
;
4900 /* And GNU code determines whether or not to get register information
4901 by passing null for the REGS argument to re_match, etc., not by
4905 /* Match anchors at newline. */
4906 bufp
->newline_anchor
= 1;
4908 ret
= regex_compile (pattern
, length
, re_syntax_options
, bufp
);
4910 return re_error_msg
[(int) ret
];
4913 /* Entry points compatible with 4.2 BSD regex library. We don't define
4914 them if this is an Emacs or POSIX compilation. */
4916 #if !defined (emacs) && !defined (_POSIX_SOURCE)
4918 /* BSD has one and only one pattern buffer. */
4919 static struct re_pattern_buffer re_comp_buf
;
4929 if (!re_comp_buf
.buffer
)
4930 return "No previous regular expression";
4934 if (!re_comp_buf
.buffer
)
4936 re_comp_buf
.buffer
= (unsigned char *) malloc (200);
4937 if (re_comp_buf
.buffer
== NULL
)
4938 return "Memory exhausted";
4939 re_comp_buf
.allocated
= 200;
4941 re_comp_buf
.fastmap
= (char *) malloc (1 << BYTEWIDTH
);
4942 if (re_comp_buf
.fastmap
== NULL
)
4943 return "Memory exhausted";
4946 /* Since `re_exec' always passes NULL for the `regs' argument, we
4947 don't need to initialize the pattern buffer fields which affect it. */
4949 /* Match anchors at newlines. */
4950 re_comp_buf
.newline_anchor
= 1;
4952 ret
= regex_compile (s
, strlen (s
), re_syntax_options
, &re_comp_buf
);
4954 /* Yes, we're discarding `const' here. */
4955 return (char *) re_error_msg
[(int) ret
];
4963 const int len
= strlen (s
);
4965 0 <= re_search (&re_comp_buf
, s
, len
, 0, len
, (struct re_registers
*) 0);
4967 #endif /* not emacs and not _POSIX_SOURCE */
4969 /* POSIX.2 functions. Don't define these for Emacs. */
4973 /* regcomp takes a regular expression as a string and compiles it.
4975 PREG is a regex_t *. We do not expect any fields to be initialized,
4976 since POSIX says we shouldn't. Thus, we set
4978 `buffer' to the compiled pattern;
4979 `used' to the length of the compiled pattern;
4980 `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
4981 REG_EXTENDED bit in CFLAGS is set; otherwise, to
4982 RE_SYNTAX_POSIX_BASIC;
4983 `newline_anchor' to REG_NEWLINE being set in CFLAGS;
4984 `fastmap' and `fastmap_accurate' to zero;
4985 `re_nsub' to the number of subexpressions in PATTERN.
4987 PATTERN is the address of the pattern string.
4989 CFLAGS is a series of bits which affect compilation.
4991 If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
4992 use POSIX basic syntax.
4994 If REG_NEWLINE is set, then . and [^...] don't match newline.
4995 Also, regexec will try a match beginning after every newline.
4997 If REG_ICASE is set, then we considers upper- and lowercase
4998 versions of letters to be equivalent when matching.
5000 If REG_NOSUB is set, then when PREG is passed to regexec, that
5001 routine will report only success or failure, and nothing about the
5004 It returns 0 if it succeeds, nonzero if it doesn't. (See regex.h for
5005 the return codes and their meanings.) */
5008 regcomp (preg
, pattern
, cflags
)
5010 const char *pattern
;
5015 = (cflags
& REG_EXTENDED
) ?
5016 RE_SYNTAX_POSIX_EXTENDED
: RE_SYNTAX_POSIX_BASIC
;
5018 /* regex_compile will allocate the space for the compiled pattern. */
5020 preg
->allocated
= 0;
5023 /* Don't bother to use a fastmap when searching. This simplifies the
5024 REG_NEWLINE case: if we used a fastmap, we'd have to put all the
5025 characters after newlines into the fastmap. This way, we just try
5029 if (cflags
& REG_ICASE
)
5033 preg
->translate
= (char *) malloc (CHAR_SET_SIZE
);
5034 if (preg
->translate
== NULL
)
5035 return (int) REG_ESPACE
;
5037 /* Map uppercase characters to corresponding lowercase ones. */
5038 for (i
= 0; i
< CHAR_SET_SIZE
; i
++)
5039 preg
->translate
[i
] = ISUPPER (i
) ? tolower (i
) : i
;
5042 preg
->translate
= NULL
;
5044 /* If REG_NEWLINE is set, newlines are treated differently. */
5045 if (cflags
& REG_NEWLINE
)
5046 { /* REG_NEWLINE implies neither . nor [^...] match newline. */
5047 syntax
&= ~RE_DOT_NEWLINE
;
5048 syntax
|= RE_HAT_LISTS_NOT_NEWLINE
;
5049 /* It also changes the matching behavior. */
5050 preg
->newline_anchor
= 1;
5053 preg
->newline_anchor
= 0;
5055 preg
->no_sub
= !!(cflags
& REG_NOSUB
);
5057 /* POSIX says a null character in the pattern terminates it, so we
5058 can use strlen here in compiling the pattern. */
5059 ret
= regex_compile (pattern
, strlen (pattern
), syntax
, preg
);
5061 /* POSIX doesn't distinguish between an unmatched open-group and an
5062 unmatched close-group: both are REG_EPAREN. */
5063 if (ret
== REG_ERPAREN
) ret
= REG_EPAREN
;
5069 /* regexec searches for a given pattern, specified by PREG, in the
5072 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
5073 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
5074 least NMATCH elements, and we set them to the offsets of the
5075 corresponding matched substrings.
5077 EFLAGS specifies `execution flags' which affect matching: if
5078 REG_NOTBOL is set, then ^ does not match at the beginning of the
5079 string; if REG_NOTEOL is set, then $ does not match at the end.
5081 We return 0 if we find a match and REG_NOMATCH if not. */
5084 regexec (preg
, string
, nmatch
, pmatch
, eflags
)
5085 const regex_t
*preg
;
5088 regmatch_t pmatch
[];
5092 struct re_registers regs
;
5093 regex_t private_preg
;
5094 int len
= strlen (string
);
5095 boolean want_reg_info
= !preg
->no_sub
&& nmatch
> 0;
5097 private_preg
= *preg
;
5099 private_preg
.not_bol
= !!(eflags
& REG_NOTBOL
);
5100 private_preg
.not_eol
= !!(eflags
& REG_NOTEOL
);
5102 /* The user has told us exactly how many registers to return
5103 information about, via `nmatch'. We have to pass that on to the
5104 matching routines. */
5105 private_preg
.regs_allocated
= REGS_FIXED
;
5109 regs
.num_regs
= nmatch
;
5110 regs
.start
= TALLOC (nmatch
, regoff_t
);
5111 regs
.end
= TALLOC (nmatch
, regoff_t
);
5112 if (regs
.start
== NULL
|| regs
.end
== NULL
)
5113 return (int) REG_NOMATCH
;
5116 /* Perform the searching operation. */
5117 ret
= re_search (&private_preg
, string
, len
,
5118 /* start: */ 0, /* range: */ len
,
5119 want_reg_info
? ®s
: (struct re_registers
*) 0);
5121 /* Copy the register information to the POSIX structure. */
5128 for (r
= 0; r
< nmatch
; r
++)
5130 pmatch
[r
].rm_so
= regs
.start
[r
];
5131 pmatch
[r
].rm_eo
= regs
.end
[r
];
5135 /* If we needed the temporary register info, free the space now. */
5140 /* We want zero return to mean success, unlike `re_search'. */
5141 return ret
>= 0 ? (int) REG_NOERROR
: (int) REG_NOMATCH
;
5145 /* Returns a message corresponding to an error code, ERRCODE, returned
5146 from either regcomp or regexec. We don't use PREG here. */
5149 regerror (errcode
, preg
, errbuf
, errbuf_size
)
5151 const regex_t
*preg
;
5159 || errcode
>= (sizeof (re_error_msg
) / sizeof (re_error_msg
[0])))
5160 /* Only error codes returned by the rest of the code should be passed
5161 to this routine. If we are given anything else, or if other regex
5162 code generates an invalid error code, then the program has a bug.
5163 Dump core so we can fix it. */
5166 msg
= re_error_msg
[errcode
];
5168 /* POSIX doesn't require that we do anything in this case, but why
5173 msg_size
= strlen (msg
) + 1; /* Includes the null. */
5175 if (errbuf_size
!= 0)
5177 if (msg_size
> errbuf_size
)
5179 strncpy (errbuf
, msg
, errbuf_size
- 1);
5180 errbuf
[errbuf_size
- 1] = 0;
5183 strcpy (errbuf
, msg
);
5190 /* Free dynamically allocated space used by PREG. */
5196 if (preg
->buffer
!= NULL
)
5197 free (preg
->buffer
);
5198 preg
->buffer
= NULL
;
5200 preg
->allocated
= 0;
5203 if (preg
->fastmap
!= NULL
)
5204 free (preg
->fastmap
);
5205 preg
->fastmap
= NULL
;
5206 preg
->fastmap_accurate
= 0;
5208 if (preg
->translate
!= NULL
)
5209 free (preg
->translate
);
5210 preg
->translate
= NULL
;
5213 #endif /* not emacs */
5217 make-backup-files: t
5219 trim-versions-without-asking: nil