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*/
This source file includes following definitions.
- init_syntax_once
- extract_number
- extract_number_and_incr
- print_fastmap
- print_partial_compiled_pattern
- print_compiled_pattern
- print_double_string
- printchar
- re_set_syntax
- regex_grow_registers
- regex_compile
- store_op1
- store_op2
- insert_op1
- insert_op2
- at_begline_loc_p
- at_endline_loc_p
- group_in_compile_stack
- compile_range
- re_compile_fastmap
- weak_alias
- weak_alias
- weak_alias
- re_match
- weak_alias
- weak_alias
- group_match_null_string_p
- alt_match_null_string_p
- common_op_match_null_string_p
- bcmp_translate
- re_compile_pattern
- weak_alias
- re_exec
- regcomp
- weak_alias
- weak_alias
- weak_alias
1 /* Extended regular expression matching and search library,
2 version 0.12.
3 (Implements POSIX draft P1003.2/D11.2, except for some of the
4 internationalization features.)
5 Copyright (C) 1993-1999, 2000 Free Software Foundation, Inc.
6
7 The GNU C Library is free software; you can redistribute it and/or
8 modify it under the terms of the GNU Library General Public License as
9 published by the Free Software Foundation; either version 2 of the
10 License, or (at your option) any later version.
11
12 The GNU C Library is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Library General Public License for more details.
16
17 You should have received a copy of the GNU Library General Public
18 License along with the GNU C Library; see the file COPYING.LIB. If not,
19 write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
20 Boston, MA 02110-1301 USA. */
21
22 /* AIX requires this to be the first thing in the file. */
23 #if defined _AIX && !defined REGEX_MALLOC
24 #pragma alloca
25 #endif
26
27 #undef _GNU_SOURCE
28 #define _GNU_SOURCE
29
30 #ifdef HAVE_CONFIG_H
31 # include <config.h>
32 #endif
33
34 #ifndef PARAMS
35 # if defined __GNUC__ || (defined __STDC__ && __STDC__)
36 # define PARAMS(args) args
37 # else
38 # define PARAMS(args) ()
39 # endif /* GCC. */
40 #endif /* Not PARAMS. */
41
42 #if defined STDC_HEADERS && !defined emacs
43 # include <stddef.h>
44 #else
45 /* We need this for `regex.h', and perhaps for the Emacs include files. */
46 # include <sys/types.h>
47 #endif
48
49 #define WIDE_CHAR_SUPPORT (HAVE_WCTYPE_H && HAVE_WCHAR_H && HAVE_BTOWC)
50
51 /* For platform which support the ISO C amendement 1 functionality we
52 support user defined character classes. */
53 #if defined _LIBC || WIDE_CHAR_SUPPORT
54 /* Solaris 2.5 has a bug: <wchar.h> must be included before <wctype.h>. */
55 # include <wchar.h>
56 # include <wctype.h>
57 #endif
58
59 #ifdef _LIBC
60 /* We have to keep the namespace clean. */
61 # define regfree(preg) __regfree (preg)
62 # define regexec(pr, st, nm, pm, ef) __regexec (pr, st, nm, pm, ef)
63 # define regcomp(preg, pattern, cflags) __regcomp (preg, pattern, cflags)
64 # define regerror(errcode, preg, errbuf, errbuf_size) \
65 __regerror(errcode, preg, errbuf, errbuf_size)
66 # define re_set_registers(bu, re, nu, st, en) \
67 __re_set_registers (bu, re, nu, st, en)
68 # define re_match_2(bufp, string1, size1, string2, size2, pos, regs, stop) \
69 __re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
70 # define re_match(bufp, string, size, pos, regs) \
71 __re_match (bufp, string, size, pos, regs)
72 # define re_search(bufp, string, size, startpos, range, regs) \
73 __re_search (bufp, string, size, startpos, range, regs)
74 # define re_compile_pattern(pattern, length, bufp) \
75 __re_compile_pattern (pattern, length, bufp)
76 # define re_set_syntax(syntax) __re_set_syntax (syntax)
77 # define re_search_2(bufp, st1, s1, st2, s2, startpos, range, regs, stop) \
78 __re_search_2 (bufp, st1, s1, st2, s2, startpos, range, regs, stop)
79 # define re_compile_fastmap(bufp) __re_compile_fastmap (bufp)
80
81 #define btowc __btowc
82 #endif
83
84 /* This is for other GNU distributions with internationalized messages. */
85 #if HAVE_LIBINTL_H || defined _LIBC
86 # include <libintl.h>
87 #else
88 # define gettext(msgid) (msgid)
89 #endif
90
91 #ifndef gettext_noop
92 /* This define is so xgettext can find the internationalizable
93 strings. */
94 # define gettext_noop(String) String
95 #endif
96
97 /* The `emacs' switch turns on certain matching commands
98 that make sense only in Emacs. */
99 #ifdef emacs
100
101 # include "lisp.h"
102 # include "buffer.h"
103 # include "syntax.h"
104
105 #else /* not emacs */
106
107 /* If we are not linking with Emacs proper,
108 we can't use the relocating allocator
109 even if config.h says that we can. */
110 # undef REL_ALLOC
111
112 # if defined STDC_HEADERS || defined _LIBC
113 # include <stdlib.h>
114 # else
115 char *malloc ();
116 char *realloc ();
117 # endif
118
119 /* When used in Emacs's lib-src, we need to get bzero and bcopy somehow.
120 If nothing else has been done, use the method below. */
121 # ifdef INHIBIT_STRING_HEADER
122 # if !(defined HAVE_BZERO && defined HAVE_BCOPY)
123 # if !defined bzero && !defined bcopy
124 # undef INHIBIT_STRING_HEADER
125 # endif
126 # endif
127 # endif
128
129 /* This is the normal way of making sure we have a bcopy and a bzero.
130 This is used in most programs--a few other programs avoid this
131 by defining INHIBIT_STRING_HEADER. */
132 # ifndef INHIBIT_STRING_HEADER
133 # if defined HAVE_STRING_H || defined STDC_HEADERS || defined _LIBC
134 # include <string.h>
135 # ifndef bzero
136 # ifndef _LIBC
137 # define bzero(s, n) (memset (s, '\0', n), (s))
138 # else
139 # define bzero(s, n) __bzero (s, n)
140 # endif
141 # endif
142 # else
143 # include <strings.h>
144 # ifndef memcmp
145 # define memcmp(s1, s2, n) bcmp (s1, s2, n)
146 # endif
147 # ifndef memcpy
148 # define memcpy(d, s, n) (bcopy (s, d, n), (d))
149 # endif
150 # endif
151 # endif
152
153 /* Define the syntax stuff for \<, \>, etc. */
154
155 /* This must be nonzero for the wordchar and notwordchar pattern
156 commands in re_match_2. */
157 # ifndef Sword
158 # define Sword 1
159 # endif
160
161 # ifdef SWITCH_ENUM_BUG
162 # define SWITCH_ENUM_CAST(x) ((int)(x))
163 # else
164 # define SWITCH_ENUM_CAST(x) (x)
165 # endif
166
167 #endif /* not emacs */
168
169 /* Get the interface, including the syntax bits. */
170 #include <regex.h>
171
172 /* isalpha etc. are used for the character classes. */
173 #include <ctype.h>
174
175 /* Jim Meyering writes:
176
177 "... Some ctype macros are valid only for character codes that
178 isascii says are ASCII (SGI's IRIX-4.0.5 is one such system --when
179 using /bin/cc or gcc but without giving an ansi option). So, all
180 ctype uses should be through macros like ISPRINT... If
181 STDC_HEADERS is defined, then autoconf has verified that the ctype
182 macros don't need to be guarded with references to isascii. ...
183 Defining isascii to 1 should let any compiler worth its salt
184 eliminate the && through constant folding."
185 Solaris defines some of these symbols so we must undefine them first. */
186
187 #undef ISASCII
188 #if defined STDC_HEADERS || (!defined isascii && !defined HAVE_ISASCII)
189 # define ISASCII(c) 1
190 #else
191 # define ISASCII(c) isascii(c)
192 #endif
193
194 #ifdef isblank
195 # define ISBLANK(c) (ISASCII (c) && isblank (c))
196 #else
197 # define ISBLANK(c) ((c) == ' ' || (c) == '\t')
198 #endif
199 #ifdef isgraph
200 # define ISGRAPH(c) (ISASCII (c) && isgraph (c))
201 #else
202 # define ISGRAPH(c) (ISASCII (c) && isprint (c) && !isspace (c))
203 #endif
204
205 #undef ISPRINT
206 #define ISPRINT(c) (ISASCII (c) && isprint (c))
207 #define ISDIGIT(c) (ISASCII (c) && isdigit (c))
208 #define ISALNUM(c) (ISASCII (c) && isalnum (c))
209 #define ISALPHA(c) (ISASCII (c) && isalpha (c))
210 #define ISCNTRL(c) (ISASCII (c) && iscntrl (c))
211 #define ISLOWER(c) (ISASCII (c) && islower (c))
212 #define ISPUNCT(c) (ISASCII (c) && ispunct (c))
213 #define ISSPACE(c) (ISASCII (c) && isspace (c))
214 #define ISUPPER(c) (ISASCII (c) && isupper (c))
215 #define ISXDIGIT(c) (ISASCII (c) && isxdigit (c))
216
217 #ifdef _tolower
218 # define TOLOWER(c) _tolower(c)
219 #else
220 # define TOLOWER(c) tolower(c)
221 #endif
222
223 #ifndef NULL
224 # define NULL (void *)0
225 #endif
226
227 /* We remove any previous definition of `SIGN_EXTEND_CHAR',
228 since ours (we hope) works properly with all combinations of
229 machines, compilers, `char' and `unsigned char' argument types.
230 (Per Bothner suggested the basic approach.) */
231 #undef SIGN_EXTEND_CHAR
232 #if __STDC__
233 # define SIGN_EXTEND_CHAR(c) ((signed char) (c))
234 #else /* not __STDC__ */
235 /* As in Harbison and Steele. */
236 # define SIGN_EXTEND_CHAR(c) ((((unsigned char) (c)) ^ 128) - 128)
237 #endif
238
239 #ifndef emacs
240 /* How many characters in the character set. */
241 # define CHAR_SET_SIZE 256
242
243 # ifdef SYNTAX_TABLE
244
245 extern char *re_syntax_table;
246
247 # else /* not SYNTAX_TABLE */
248
249 static char re_syntax_table[CHAR_SET_SIZE];
250
251 static void
252 init_syntax_once ()
253 {
254 register int c;
255 static int done = 0;
256
257 if (done)
258 return;
259 bzero (re_syntax_table, sizeof re_syntax_table);
260
261 for (c = 0; c < CHAR_SET_SIZE; ++c)
262 if (ISALNUM (c))
263 re_syntax_table[c] = Sword;
264
265 re_syntax_table['_'] = Sword;
266
267 done = 1;
268 }
269
270 # endif /* not SYNTAX_TABLE */
271
272 # define SYNTAX(c) re_syntax_table[((c) & 0xFF)]
273
274 #endif /* emacs */
275
276 /* Should we use malloc or alloca? If REGEX_MALLOC is not defined, we
277 use `alloca' instead of `malloc'. This is because using malloc in
278 re_search* or re_match* could cause memory leaks when C-g is used in
279 Emacs; also, malloc is slower and causes storage fragmentation. On
280 the other hand, malloc is more portable, and easier to debug.
281
282 Because we sometimes use alloca, some routines have to be macros,
283 not functions -- `alloca'-allocated space disappears at the end of the
284 function it is called in. */
285
286 #ifdef REGEX_MALLOC
287
288 # define REGEX_ALLOCATE malloc
289 # define REGEX_REALLOCATE(source, osize, nsize) realloc (source, nsize)
290 # define REGEX_FREE free
291
292 #else /* not REGEX_MALLOC */
293
294 /* Emacs already defines alloca, sometimes. */
295 # ifndef alloca
296
297 /* Make alloca work the best possible way. */
298 # ifdef __GNUC__
299 # define alloca __builtin_alloca
300 # else /* not __GNUC__ */
301 # if HAVE_ALLOCA_H
302 # include <alloca.h>
303 # endif /* HAVE_ALLOCA_H */
304 # endif /* not __GNUC__ */
305
306 # endif /* not alloca */
307
308 # define REGEX_ALLOCATE alloca
309
310 /* Assumes a `char *destination' variable. */
311 # define REGEX_REALLOCATE(source, osize, nsize) \
312 (destination = (char *) alloca (nsize), \
313 memcpy (destination, source, osize))
314
315 /* No need to do anything to free, after alloca. */
316 # define REGEX_FREE(arg) ((void)0) /* Do nothing! But inhibit gcc warning. */
317
318 #endif /* not REGEX_MALLOC */
319
320 /* Define how to allocate the failure stack. */
321
322 #if defined REL_ALLOC && defined REGEX_MALLOC
323
324 # define REGEX_ALLOCATE_STACK(size) \
325 r_alloc (&failure_stack_ptr, (size))
326 # define REGEX_REALLOCATE_STACK(source, osize, nsize) \
327 r_re_alloc (&failure_stack_ptr, (nsize))
328 # define REGEX_FREE_STACK(ptr) \
329 r_alloc_free (&failure_stack_ptr)
330
331 #else /* not using relocating allocator */
332
333 # ifdef REGEX_MALLOC
334
335 # define REGEX_ALLOCATE_STACK malloc
336 # define REGEX_REALLOCATE_STACK(source, osize, nsize) realloc (source, nsize)
337 # define REGEX_FREE_STACK free
338
339 # else /* not REGEX_MALLOC */
340
341 # define REGEX_ALLOCATE_STACK alloca
342
343 # define REGEX_REALLOCATE_STACK(source, osize, nsize) \
344 REGEX_REALLOCATE (source, osize, nsize)
345 /* No need to explicitly free anything. */
346 # define REGEX_FREE_STACK(arg)
347
348 # endif /* not REGEX_MALLOC */
349 #endif /* not using relocating allocator */
350
351
352 /* True if `size1' is non-NULL and PTR is pointing anywhere inside
353 `string1' or just past its end. This works if PTR is NULL, which is
354 a good thing. */
355 #define FIRST_STRING_P(ptr) \
356 (size1 && string1 <= (ptr) && (ptr) <= string1 + size1)
357
358 /* (Re)Allocate N items of type T using malloc, or fail. */
359 #define TALLOC(n, t) ((t *) malloc ((n) * sizeof (t)))
360 #define RETALLOC(addr, n, t) ((addr) = (t *) realloc (addr, (n) * sizeof (t)))
361 #define RETALLOC_IF(addr, n, t) \
362 if (addr) RETALLOC((addr), (n), t); else (addr) = TALLOC ((n), t)
363 #define REGEX_TALLOC(n, t) ((t *) REGEX_ALLOCATE ((n) * sizeof (t)))
364
365 #define BYTEWIDTH 8 /* In bits. */
366
367 #define STREQ(s1, s2) ((strcmp (s1, s2) == 0))
368
369 #undef MAX
370 #undef MIN
371 #define MAX(a, b) ((a) > (b) ? (a) : (b))
372 #define MIN(a, b) ((a) < (b) ? (a) : (b))
373
374 typedef char boolean;
375 #define false 0
376 #define true 1
377
378 static int re_match_2_internal PARAMS ((struct re_pattern_buffer *bufp,
379 const char *string1, int size1,
380 const char *string2, int size2,
381 int pos,
382 struct re_registers *regs,
383 int stop));
384
385 /* These are the command codes that appear in compiled regular
386 expressions. Some opcodes are followed by argument bytes. A
387 command code can specify any interpretation whatsoever for its
388 arguments. Zero bytes may appear in the compiled regular expression. */
389
390 typedef enum
391 {
392 no_op = 0,
393
394 /* Succeed right away--no more backtracking. */
395 succeed,
396
397 /* Followed by one byte giving n, then by n literal bytes. */
398 exactn,
399
400 /* Matches any (more or less) character. */
401 anychar,
402
403 /* Matches any one char belonging to specified set. First
404 following byte is number of bitmap bytes. Then come bytes
405 for a bitmap saying which chars are in. Bits in each byte
406 are ordered low-bit-first. A character is in the set if its
407 bit is 1. A character too large to have a bit in the map is
408 automatically not in the set. */
409 charset,
410
411 /* Same parameters as charset, but match any character that is
412 not one of those specified. */
413 charset_not,
414
415 /* Start remembering the text that is matched, for storing in a
416 register. Followed by one byte with the register number, in
417 the range 0 to one less than the pattern buffer's re_nsub
418 field. Then followed by one byte with the number of groups
419 inner to this one. (This last has to be part of the
420 start_memory only because we need it in the on_failure_jump
421 of re_match_2.) */
422 start_memory,
423
424 /* Stop remembering the text that is matched and store it in a
425 memory register. Followed by one byte with the register
426 number, in the range 0 to one less than `re_nsub' in the
427 pattern buffer, and one byte with the number of inner groups,
428 just like `start_memory'. (We need the number of inner
429 groups here because we don't have any easy way of finding the
430 corresponding start_memory when we're at a stop_memory.) */
431 stop_memory,
432
433 /* Match a duplicate of something remembered. Followed by one
434 byte containing the register number. */
435 duplicate,
436
437 /* Fail unless at beginning of line. */
438 begline,
439
440 /* Fail unless at end of line. */
441 endline,
442
443 /* Succeeds if at beginning of buffer (if emacs) or at beginning
444 of string to be matched (if not). */
445 begbuf,
446
447 /* Analogously, for end of buffer/string. */
448 endbuf,
449
450 /* Followed by two byte relative address to which to jump. */
451 jump,
452
453 /* Same as jump, but marks the end of an alternative. */
454 jump_past_alt,
455
456 /* Followed by two-byte relative address of place to resume at
457 in case of failure. */
458 on_failure_jump,
459
460 /* Like on_failure_jump, but pushes a placeholder instead of the
461 current string position when executed. */
462 on_failure_keep_string_jump,
463
464 /* Throw away latest failure point and then jump to following
465 two-byte relative address. */
466 pop_failure_jump,
467
468 /* Change to pop_failure_jump if know won't have to backtrack to
469 match; otherwise change to jump. This is used to jump
470 back to the beginning of a repeat. If what follows this jump
471 clearly won't match what the repeat does, such that we can be
472 sure that there is no use backtracking out of repetitions
473 already matched, then we change it to a pop_failure_jump.
474 Followed by two-byte address. */
475 maybe_pop_jump,
476
477 /* Jump to following two-byte address, and push a dummy failure
478 point. This failure point will be thrown away if an attempt
479 is made to use it for a failure. A `+' construct makes this
480 before the first repeat. Also used as an intermediary kind
481 of jump when compiling an alternative. */
482 dummy_failure_jump,
483
484 /* Push a dummy failure point and continue. Used at the end of
485 alternatives. */
486 push_dummy_failure,
487
488 /* Followed by two-byte relative address and two-byte number n.
489 After matching N times, jump to the address upon failure. */
490 succeed_n,
491
492 /* Followed by two-byte relative address, and two-byte number n.
493 Jump to the address N times, then fail. */
494 jump_n,
495
496 /* Set the following two-byte relative address to the
497 subsequent two-byte number. The address *includes* the two
498 bytes of number. */
499 set_number_at,
500
501 wordchar, /* Matches any word-constituent character. */
502 notwordchar, /* Matches any char that is not a word-constituent. */
503
504 wordbeg, /* Succeeds if at word beginning. */
505 wordend, /* Succeeds if at word end. */
506
507 wordbound, /* Succeeds if at a word boundary. */
508 notwordbound /* Succeeds if not at a word boundary. */
509
510 #ifdef emacs
511 ,before_dot, /* Succeeds if before point. */
512 at_dot, /* Succeeds if at point. */
513 after_dot, /* Succeeds if after point. */
514
515 /* Matches any character whose syntax is specified. Followed by
516 a byte which contains a syntax code, e.g., Sword. */
517 syntaxspec,
518
519 /* Matches any character whose syntax is not that specified. */
520 notsyntaxspec
521 #endif /* emacs */
522 } re_opcode_t;
523
524 /* Common operations on the compiled pattern. */
525
526 /* Store NUMBER in two contiguous bytes starting at DESTINATION. */
527
528 #define STORE_NUMBER(destination, number) \
529 do { \
530 (destination)[0] = (number) & 0377; \
531 (destination)[1] = (number) >> 8; \
532 } while (0)
533
534 /* Same as STORE_NUMBER, except increment DESTINATION to
535 the byte after where the number is stored. Therefore, DESTINATION
536 must be an lvalue. */
537
538 #define STORE_NUMBER_AND_INCR(destination, number) \
539 do { \
540 STORE_NUMBER (destination, number); \
541 (destination) += 2; \
542 } while (0)
543
544 /* Put into DESTINATION a number stored in two contiguous bytes starting
545 at SOURCE. */
546
547 #define EXTRACT_NUMBER(destination, source) \
548 do { \
549 (destination) = *(source) & 0377; \
550 (destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8; \
551 } while (0)
552
553 #ifdef DEBUG
554 static void extract_number _RE_ARGS ((int *dest, unsigned char *source));
555 static void
556 extract_number (dest, source)
557 int *dest;
558 unsigned char *source;
559 {
560 int temp = SIGN_EXTEND_CHAR (*(source + 1));
561 *dest = *source & 0377;
562 *dest += temp << 8;
563 }
564
565 # ifndef EXTRACT_MACROS /* To debug the macros. */
566 # undef EXTRACT_NUMBER
567 # define EXTRACT_NUMBER(dest, src) extract_number (&dest, src)
568 # endif /* not EXTRACT_MACROS */
569
570 #endif /* DEBUG */
571
572 /* Same as EXTRACT_NUMBER, except increment SOURCE to after the number.
573 SOURCE must be an lvalue. */
574
575 #define EXTRACT_NUMBER_AND_INCR(destination, source) \
576 do { \
577 EXTRACT_NUMBER (destination, source); \
578 (source) += 2; \
579 } while (0)
580
581 #ifdef DEBUG
582 static void extract_number_and_incr _RE_ARGS ((int *destination,
583 unsigned char **source));
584 static void
585 extract_number_and_incr (destination, source)
586 int *destination;
587 unsigned char **source;
588 {
589 extract_number (destination, *source);
590 *source += 2;
591 }
592
593 # ifndef EXTRACT_MACROS
594 # undef EXTRACT_NUMBER_AND_INCR
595 # define EXTRACT_NUMBER_AND_INCR(dest, src) \
596 extract_number_and_incr (&dest, &src)
597 # endif /* not EXTRACT_MACROS */
598
599 #endif /* DEBUG */
600
601 /* If DEBUG is defined, Regex prints many voluminous messages about what
602 it is doing (if the variable `debug' is nonzero). If linked with the
603 main program in `iregex.c', you can enter patterns and strings
604 interactively. And if linked with the main program in `main.c' and
605 the other test files, you can run the already-written tests. */
606
607 #ifdef DEBUG
608
609 /* We use standard I/O for debugging. */
610 # include <stdio.h>
611
612 /* It is useful to test things that ``must'' be true when debugging. */
613 # include <assert.h>
614
615 static int debug;
616
617 # define DEBUG_STATEMENT(e) e
618 # define DEBUG_PRINT1(x) if (debug) printf (x)
619 # define DEBUG_PRINT2(x1, x2) if (debug) printf (x1, x2)
620 # define DEBUG_PRINT3(x1, x2, x3) if (debug) printf (x1, x2, x3)
621 # define DEBUG_PRINT4(x1, x2, x3, x4) if (debug) printf (x1, x2, x3, x4)
622 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e) \
623 if (debug) print_partial_compiled_pattern (s, e)
624 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2) \
625 if (debug) print_double_string (w, s1, sz1, s2, sz2)
626
627
628 /* Print the fastmap in human-readable form. */
629
630 void
631 print_fastmap (fastmap)
632 char *fastmap;
633 {
634 unsigned was_a_range = 0;
635 unsigned i = 0;
636
637 while (i < (1 << BYTEWIDTH))
638 {
639 if (fastmap[i++])
640 {
641 was_a_range = 0;
642 putchar (i - 1);
643 while (i < (1 << BYTEWIDTH) && fastmap[i])
644 {
645 was_a_range = 1;
646 i++;
647 }
648 if (was_a_range)
649 {
650 printf ("-");
651 putchar (i - 1);
652 }
653 }
654 }
655 putchar ('\n');
656 }
657
658
659 /* Print a compiled pattern string in human-readable form, starting at
660 the START pointer into it and ending just before the pointer END. */
661
662 void
663 print_partial_compiled_pattern (start, end)
664 unsigned char *start;
665 unsigned char *end;
666 {
667 int mcnt, mcnt2;
668 unsigned char *p1;
669 unsigned char *p = start;
670 unsigned char *pend = end;
671
672 if (start == NULL)
673 {
674 printf ("(null)\n");
675 return;
676 }
677
678 /* Loop over pattern commands. */
679 while (p < pend)
680 {
681 printf ("%d:\t", p - start);
682
683 switch ((re_opcode_t) *p++)
684 {
685 case no_op:
686 printf ("/no_op");
687 break;
688
689 case exactn:
690 mcnt = *p++;
691 printf ("/exactn/%d", mcnt);
692 do
693 {
694 putchar ('/');
695 putchar (*p++);
696 }
697 while (--mcnt);
698 break;
699
700 case start_memory:
701 mcnt = *p++;
702 printf ("/start_memory/%d/%d", mcnt, *p++);
703 break;
704
705 case stop_memory:
706 mcnt = *p++;
707 printf ("/stop_memory/%d/%d", mcnt, *p++);
708 break;
709
710 case duplicate:
711 printf ("/duplicate/%d", *p++);
712 break;
713
714 case anychar:
715 printf ("/anychar");
716 break;
717
718 case charset:
719 case charset_not:
720 {
721 register int c, last = -100;
722 register int in_range = 0;
723
724 printf ("/charset [%s",
725 (re_opcode_t) *(p - 1) == charset_not ? "^" : "");
726
727 assert (p + *p < pend);
728
729 for (c = 0; c < 256; c++)
730 if (c / 8 < *p
731 && (p[1 + (c/8)] & (1 << (c % 8))))
732 {
733 /* Are we starting a range? */
734 if (last + 1 == c && ! in_range)
735 {
736 putchar ('-');
737 in_range = 1;
738 }
739 /* Have we broken a range? */
740 else if (last + 1 != c && in_range)
741 {
742 putchar (last);
743 in_range = 0;
744 }
745
746 if (! in_range)
747 putchar (c);
748
749 last = c;
750 }
751
752 if (in_range)
753 putchar (last);
754
755 putchar (']');
756
757 p += 1 + *p;
758 }
759 break;
760
761 case begline:
762 printf ("/begline");
763 break;
764
765 case endline:
766 printf ("/endline");
767 break;
768
769 case on_failure_jump:
770 extract_number_and_incr (&mcnt, &p);
771 printf ("/on_failure_jump to %d", p + mcnt - start);
772 break;
773
774 case on_failure_keep_string_jump:
775 extract_number_and_incr (&mcnt, &p);
776 printf ("/on_failure_keep_string_jump to %d", p + mcnt - start);
777 break;
778
779 case dummy_failure_jump:
780 extract_number_and_incr (&mcnt, &p);
781 printf ("/dummy_failure_jump to %d", p + mcnt - start);
782 break;
783
784 case push_dummy_failure:
785 printf ("/push_dummy_failure");
786 break;
787
788 case maybe_pop_jump:
789 extract_number_and_incr (&mcnt, &p);
790 printf ("/maybe_pop_jump to %d", p + mcnt - start);
791 break;
792
793 case pop_failure_jump:
794 extract_number_and_incr (&mcnt, &p);
795 printf ("/pop_failure_jump to %d", p + mcnt - start);
796 break;
797
798 case jump_past_alt:
799 extract_number_and_incr (&mcnt, &p);
800 printf ("/jump_past_alt to %d", p + mcnt - start);
801 break;
802
803 case jump:
804 extract_number_and_incr (&mcnt, &p);
805 printf ("/jump to %d", p + mcnt - start);
806 break;
807
808 case succeed_n:
809 extract_number_and_incr (&mcnt, &p);
810 p1 = p + mcnt;
811 extract_number_and_incr (&mcnt2, &p);
812 printf ("/succeed_n to %d, %d times", p1 - start, mcnt2);
813 break;
814
815 case jump_n:
816 extract_number_and_incr (&mcnt, &p);
817 p1 = p + mcnt;
818 extract_number_and_incr (&mcnt2, &p);
819 printf ("/jump_n to %d, %d times", p1 - start, mcnt2);
820 break;
821
822 case set_number_at:
823 extract_number_and_incr (&mcnt, &p);
824 p1 = p + mcnt;
825 extract_number_and_incr (&mcnt2, &p);
826 printf ("/set_number_at location %d to %d", p1 - start, mcnt2);
827 break;
828
829 case wordbound:
830 printf ("/wordbound");
831 break;
832
833 case notwordbound:
834 printf ("/notwordbound");
835 break;
836
837 case wordbeg:
838 printf ("/wordbeg");
839 break;
840
841 case wordend:
842 printf ("/wordend");
843
844 # ifdef emacs
845 case before_dot:
846 printf ("/before_dot");
847 break;
848
849 case at_dot:
850 printf ("/at_dot");
851 break;
852
853 case after_dot:
854 printf ("/after_dot");
855 break;
856
857 case syntaxspec:
858 printf ("/syntaxspec");
859 mcnt = *p++;
860 printf ("/%d", mcnt);
861 break;
862
863 case notsyntaxspec:
864 printf ("/notsyntaxspec");
865 mcnt = *p++;
866 printf ("/%d", mcnt);
867 break;
868 # endif /* emacs */
869
870 case wordchar:
871 printf ("/wordchar");
872 break;
873
874 case notwordchar:
875 printf ("/notwordchar");
876 break;
877
878 case begbuf:
879 printf ("/begbuf");
880 break;
881
882 case endbuf:
883 printf ("/endbuf");
884 break;
885
886 default:
887 printf ("?%d", *(p-1));
888 }
889
890 putchar ('\n');
891 }
892
893 printf ("%d:\tend of pattern.\n", p - start);
894 }
895
896
897 void
898 print_compiled_pattern (bufp)
899 struct re_pattern_buffer *bufp;
900 {
901 unsigned char *buffer = bufp->buffer;
902
903 print_partial_compiled_pattern (buffer, buffer + bufp->used);
904 printf ("%ld bytes used/%ld bytes allocated.\n",
905 bufp->used, bufp->allocated);
906
907 if (bufp->fastmap_accurate && bufp->fastmap)
908 {
909 printf ("fastmap: ");
910 print_fastmap (bufp->fastmap);
911 }
912
913 printf ("re_nsub: %d\t", bufp->re_nsub);
914 printf ("regs_alloc: %d\t", bufp->regs_allocated);
915 printf ("can_be_null: %d\t", bufp->can_be_null);
916 printf ("newline_anchor: %d\n", bufp->newline_anchor);
917 printf ("no_sub: %d\t", bufp->no_sub);
918 printf ("not_bol: %d\t", bufp->not_bol);
919 printf ("not_eol: %d\t", bufp->not_eol);
920 printf ("syntax: %lx\n", bufp->syntax);
921 /* Perhaps we should print the translate table? */
922 }
923
924
925 void
926 print_double_string (where, string1, size1, string2, size2)
927 const char *where;
928 const char *string1;
929 const char *string2;
930 int size1;
931 int size2;
932 {
933 int this_char;
934
935 if (where == NULL)
936 printf ("(null)");
937 else
938 {
939 if (FIRST_STRING_P (where))
940 {
941 for (this_char = where - string1; this_char < size1; this_char++)
942 putchar (string1[this_char]);
943
944 where = string2;
945 }
946
947 for (this_char = where - string2; this_char < size2; this_char++)
948 putchar (string2[this_char]);
949 }
950 }
951
952 void
953 printchar (c)
954 int c;
955 {
956 putc (c, stderr);
957 }
958
959 #else /* not DEBUG */
960
961 # undef assert
962 # define assert(e)
963
964 # define DEBUG_STATEMENT(e)
965 # define DEBUG_PRINT1(x)
966 # define DEBUG_PRINT2(x1, x2)
967 # define DEBUG_PRINT3(x1, x2, x3)
968 # define DEBUG_PRINT4(x1, x2, x3, x4)
969 # define DEBUG_PRINT_COMPILED_PATTERN(p, s, e)
970 # define DEBUG_PRINT_DOUBLE_STRING(w, s1, sz1, s2, sz2)
971
972 #endif /* not DEBUG */
973
974 /* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
975 also be assigned to arbitrarily: each pattern buffer stores its own
976 syntax, so it can be changed between regex compilations. */
977 /* This has no initializer because initialized variables in Emacs
978 become read-only after dumping. */
979 reg_syntax_t re_syntax_options;
980
981
982 /* Specify the precise syntax of regexps for compilation. This provides
983 for compatibility for various utilities which historically have
984 different, incompatible syntaxes.
985
986 The argument SYNTAX is a bit mask comprised of the various bits
987 defined in regex.h. We return the old syntax. */
988
989 reg_syntax_t
990 re_set_syntax (syntax)
991 reg_syntax_t syntax;
992 {
993 reg_syntax_t ret = re_syntax_options;
994
995 re_syntax_options = syntax;
996 #ifdef DEBUG
997 if (syntax & RE_DEBUG)
998 debug = 1;
999 else if (debug) /* was on but now is not */
1000 debug = 0;
1001 #endif /* DEBUG */
1002 return ret;
1003 }
1004 #ifdef _LIBC
1005 weak_alias (__re_set_syntax, re_set_syntax)
1006 #endif
1007
1008 /* This table gives an error message for each of the error codes listed
1009 in regex.h. Obviously the order here has to be same as there.
1010 POSIX doesn't require that we do anything for REG_NOERROR,
1011 but why not be nice? */
1012
1013 static const char re_error_msgid[] =
1014 {
1015 #define REG_NOERROR_IDX 0
1016 gettext_noop ("Success") /* REG_NOERROR */
1017 "\0"
1018 #define REG_NOMATCH_IDX (REG_NOERROR_IDX + sizeof "Success")
1019 gettext_noop ("No match") /* REG_NOMATCH */
1020 "\0"
1021 #define REG_BADPAT_IDX (REG_NOMATCH_IDX + sizeof "No match")
1022 gettext_noop ("Invalid regular expression") /* REG_BADPAT */
1023 "\0"
1024 #define REG_ECOLLATE_IDX (REG_BADPAT_IDX + sizeof "Invalid regular expression")
1025 gettext_noop ("Invalid collation character") /* REG_ECOLLATE */
1026 "\0"
1027 #define REG_ECTYPE_IDX (REG_ECOLLATE_IDX + sizeof "Invalid collation character")
1028 gettext_noop ("Invalid character class name") /* REG_ECTYPE */
1029 "\0"
1030 #define REG_EESCAPE_IDX (REG_ECTYPE_IDX + sizeof "Invalid character class name")
1031 gettext_noop ("Trailing backslash") /* REG_EESCAPE */
1032 "\0"
1033 #define REG_ESUBREG_IDX (REG_EESCAPE_IDX + sizeof "Trailing backslash")
1034 gettext_noop ("Invalid back reference") /* REG_ESUBREG */
1035 "\0"
1036 #define REG_EBRACK_IDX (REG_ESUBREG_IDX + sizeof "Invalid back reference")
1037 gettext_noop ("Unmatched [ or [^") /* REG_EBRACK */
1038 "\0"
1039 #define REG_EPAREN_IDX (REG_EBRACK_IDX + sizeof "Unmatched [ or [^")
1040 gettext_noop ("Unmatched ( or \\(") /* REG_EPAREN */
1041 "\0"
1042 #define REG_EBRACE_IDX (REG_EPAREN_IDX + sizeof "Unmatched ( or \\(")
1043 gettext_noop ("Unmatched \\{") /* REG_EBRACE */
1044 "\0"
1045 #define REG_BADBR_IDX (REG_EBRACE_IDX + sizeof "Unmatched \\{")
1046 gettext_noop ("Invalid content of \\{\\}") /* REG_BADBR */
1047 "\0"
1048 #define REG_ERANGE_IDX (REG_BADBR_IDX + sizeof "Invalid content of \\{\\}")
1049 gettext_noop ("Invalid range end") /* REG_ERANGE */
1050 "\0"
1051 #define REG_ESPACE_IDX (REG_ERANGE_IDX + sizeof "Invalid range end")
1052 gettext_noop ("Memory exhausted") /* REG_ESPACE */
1053 "\0"
1054 #define REG_BADRPT_IDX (REG_ESPACE_IDX + sizeof "Memory exhausted")
1055 gettext_noop ("Invalid preceding regular expression") /* REG_BADRPT */
1056 "\0"
1057 #define REG_EEND_IDX (REG_BADRPT_IDX + sizeof "Invalid preceding regular expression")
1058 gettext_noop ("Premature end of regular expression") /* REG_EEND */
1059 "\0"
1060 #define REG_ESIZE_IDX (REG_EEND_IDX + sizeof "Premature end of regular expression")
1061 gettext_noop ("Regular expression too big") /* REG_ESIZE */
1062 "\0"
1063 #define REG_ERPAREN_IDX (REG_ESIZE_IDX + sizeof "Regular expression too big")
1064 gettext_noop ("Unmatched ) or \\)") /* REG_ERPAREN */
1065 };
1066
1067 static const size_t re_error_msgid_idx[] =
1068 {
1069 REG_NOERROR_IDX,
1070 REG_NOMATCH_IDX,
1071 REG_BADPAT_IDX,
1072 REG_ECOLLATE_IDX,
1073 REG_ECTYPE_IDX,
1074 REG_EESCAPE_IDX,
1075 REG_ESUBREG_IDX,
1076 REG_EBRACK_IDX,
1077 REG_EPAREN_IDX,
1078 REG_EBRACE_IDX,
1079 REG_BADBR_IDX,
1080 REG_ERANGE_IDX,
1081 REG_ESPACE_IDX,
1082 REG_BADRPT_IDX,
1083 REG_EEND_IDX,
1084 REG_ESIZE_IDX,
1085 REG_ERPAREN_IDX
1086 };
1087
1088 /* Avoiding alloca during matching, to placate r_alloc. */
1089
1090 /* Define MATCH_MAY_ALLOCATE unless we need to make sure that the
1091 searching and matching functions should not call alloca. On some
1092 systems, alloca is implemented in terms of malloc, and if we're
1093 using the relocating allocator routines, then malloc could cause a
1094 relocation, which might (if the strings being searched are in the
1095 ralloc heap) shift the data out from underneath the regexp
1096 routines.
1097
1098 Here's another reason to avoid allocation: Emacs
1099 processes input from X in a signal handler; processing X input may
1100 call malloc; if input arrives while a matching routine is calling
1101 malloc, then we're scrod. But Emacs can't just block input while
1102 calling matching routines; then we don't notice interrupts when
1103 they come in. So, Emacs blocks input around all regexp calls
1104 except the matching calls, which it leaves unprotected, in the
1105 faith that they will not malloc. */
1106
1107 /* Normally, this is fine. */
1108 #define MATCH_MAY_ALLOCATE
1109
1110 /* When using GNU C, we are not REALLY using the C alloca, no matter
1111 what config.h may say. So don't take precautions for it. */
1112 #ifdef __GNUC__
1113 # undef C_ALLOCA
1114 #endif
1115
1116 /* The match routines may not allocate if (1) they would do it with malloc
1117 and (2) it's not safe for them to use malloc.
1118 Note that if REL_ALLOC is defined, matching would not use malloc for the
1119 failure stack, but we would still use it for the register vectors;
1120 so REL_ALLOC should not affect this. */
1121 #if (defined C_ALLOCA || defined REGEX_MALLOC) && defined emacs
1122 # undef MATCH_MAY_ALLOCATE
1123 #endif
1124
1125
1126 /* Failure stack declarations and macros; both re_compile_fastmap and
1127 re_match_2 use a failure stack. These have to be macros because of
1128 REGEX_ALLOCATE_STACK. */
1129
1130
1131 /* Number of failure points for which to initially allocate space
1132 when matching. If this number is exceeded, we allocate more
1133 space, so it is not a hard limit. */
1134 #ifndef INIT_FAILURE_ALLOC
1135 # define INIT_FAILURE_ALLOC 5
1136 #endif
1137
1138 /* Roughly the maximum number of failure points on the stack. Would be
1139 exactly that if always used MAX_FAILURE_ITEMS items each time we failed.
1140 This is a variable only so users of regex can assign to it; we never
1141 change it ourselves. */
1142
1143 #ifdef INT_IS_16BIT
1144
1145 # if defined MATCH_MAY_ALLOCATE
1146 /* 4400 was enough to cause a crash on Alpha OSF/1,
1147 whose default stack limit is 2mb. */
1148 long int re_max_failures = 4000;
1149 # else
1150 long int re_max_failures = 2000;
1151 # endif
1152
1153 union fail_stack_elt
1154 {
1155 unsigned char *pointer;
1156 long int integer;
1157 };
1158
1159 typedef union fail_stack_elt fail_stack_elt_t;
1160
1161 typedef struct
1162 {
1163 fail_stack_elt_t *stack;
1164 unsigned long int size;
1165 unsigned long int avail; /* Offset of next open position. */
1166 } fail_stack_type;
1167
1168 #else /* not INT_IS_16BIT */
1169
1170 # if defined MATCH_MAY_ALLOCATE
1171 /* 4400 was enough to cause a crash on Alpha OSF/1,
1172 whose default stack limit is 2mb. */
1173 int re_max_failures = 20000;
1174 # else
1175 int re_max_failures = 2000;
1176 # endif
1177
1178 union fail_stack_elt
1179 {
1180 unsigned char *pointer;
1181 int integer;
1182 };
1183
1184 typedef union fail_stack_elt fail_stack_elt_t;
1185
1186 typedef struct
1187 {
1188 fail_stack_elt_t *stack;
1189 unsigned size;
1190 unsigned avail; /* Offset of next open position. */
1191 } fail_stack_type;
1192
1193 #endif /* INT_IS_16BIT */
1194
1195 #define FAIL_STACK_EMPTY() (fail_stack.avail == 0)
1196 #define FAIL_STACK_PTR_EMPTY() (fail_stack_ptr->avail == 0)
1197 #define FAIL_STACK_FULL() (fail_stack.avail == fail_stack.size)
1198
1199
1200 /* Define macros to initialize and free the failure stack.
1201 Do `return -2' if the alloc fails. */
1202
1203 #ifdef MATCH_MAY_ALLOCATE
1204 # define INIT_FAIL_STACK() \
1205 do { \
1206 fail_stack.stack = (fail_stack_elt_t *) \
1207 REGEX_ALLOCATE_STACK (INIT_FAILURE_ALLOC * sizeof (fail_stack_elt_t)); \
1208 \
1209 if (fail_stack.stack == NULL) \
1210 return -2; \
1211 \
1212 fail_stack.size = INIT_FAILURE_ALLOC; \
1213 fail_stack.avail = 0; \
1214 } while (0)
1215
1216 # define RESET_FAIL_STACK() REGEX_FREE_STACK (fail_stack.stack)
1217 #else
1218 # define INIT_FAIL_STACK() \
1219 do { \
1220 fail_stack.avail = 0; \
1221 } while (0)
1222
1223 # define RESET_FAIL_STACK()
1224 #endif
1225
1226
1227 /* Double the size of FAIL_STACK, up to approximately `re_max_failures' items.
1228
1229 Return 1 if succeeds, and 0 if either ran out of memory
1230 allocating space for it or it was already too large.
1231
1232 REGEX_REALLOCATE_STACK requires `destination' be declared. */
1233
1234 #define DOUBLE_FAIL_STACK(fail_stack) \
1235 ((fail_stack).size > (unsigned) (re_max_failures * MAX_FAILURE_ITEMS) \
1236 ? 0 \
1237 : ((fail_stack).stack = (fail_stack_elt_t *) \
1238 REGEX_REALLOCATE_STACK ((fail_stack).stack, \
1239 (fail_stack).size * sizeof (fail_stack_elt_t), \
1240 ((fail_stack).size << 1) * sizeof (fail_stack_elt_t)), \
1241 \
1242 (fail_stack).stack == NULL \
1243 ? 0 \
1244 : ((fail_stack).size <<= 1, \
1245 1)))
1246
1247
1248 /* Push pointer POINTER on FAIL_STACK.
1249 Return 1 if was able to do so and 0 if ran out of memory allocating
1250 space to do so. */
1251 #define PUSH_PATTERN_OP(POINTER, FAIL_STACK) \
1252 ((FAIL_STACK_FULL () \
1253 && !DOUBLE_FAIL_STACK (FAIL_STACK)) \
1254 ? 0 \
1255 : ((FAIL_STACK).stack[(FAIL_STACK).avail++].pointer = POINTER, \
1256 1))
1257
1258 /* Push a pointer value onto the failure stack.
1259 Assumes the variable `fail_stack'. Probably should only
1260 be called from within `PUSH_FAILURE_POINT'. */
1261 #define PUSH_FAILURE_POINTER(item) \
1262 fail_stack.stack[fail_stack.avail++].pointer = (unsigned char *) (item)
1263
1264 /* This pushes an integer-valued item onto the failure stack.
1265 Assumes the variable `fail_stack'. Probably should only
1266 be called from within `PUSH_FAILURE_POINT'. */
1267 #define PUSH_FAILURE_INT(item) \
1268 fail_stack.stack[fail_stack.avail++].integer = (item)
1269
1270 /* Push a fail_stack_elt_t value onto the failure stack.
1271 Assumes the variable `fail_stack'. Probably should only
1272 be called from within `PUSH_FAILURE_POINT'. */
1273 #define PUSH_FAILURE_ELT(item) \
1274 fail_stack.stack[fail_stack.avail++] = (item)
1275
1276 /* These three POP... operations complement the three PUSH... operations.
1277 All assume that `fail_stack' is nonempty. */
1278 #define POP_FAILURE_POINTER() fail_stack.stack[--fail_stack.avail].pointer
1279 #define POP_FAILURE_INT() fail_stack.stack[--fail_stack.avail].integer
1280 #define POP_FAILURE_ELT() fail_stack.stack[--fail_stack.avail]
1281
1282 /* Used to omit pushing failure point id's when we're not debugging. */
1283 #ifdef DEBUG
1284 # define DEBUG_PUSH PUSH_FAILURE_INT
1285 # define DEBUG_POP(item_addr) *(item_addr) = POP_FAILURE_INT ()
1286 #else
1287 # define DEBUG_PUSH(item)
1288 # define DEBUG_POP(item_addr)
1289 #endif
1290
1291
1292 /* Push the information about the state we will need
1293 if we ever fail back to it.
1294
1295 Requires variables fail_stack, regstart, regend, reg_info, and
1296 num_regs_pushed be declared. DOUBLE_FAIL_STACK requires `destination'
1297 be declared.
1298
1299 Does `return FAILURE_CODE' if runs out of memory. */
1300
1301 #define PUSH_FAILURE_POINT(pattern_place, string_place, failure_code) \
1302 do { \
1303 char *destination; \
1304 /* Must be int, so when we don't save any registers, the arithmetic \
1305 of 0 + -1 isn't done as unsigned. */ \
1306 /* Can't be int, since there is not a shred of a guarantee that int \
1307 is wide enough to hold a value of something to which pointer can \
1308 be assigned */ \
1309 active_reg_t this_reg; \
1310 \
1311 DEBUG_STATEMENT (failure_id++); \
1312 DEBUG_STATEMENT (nfailure_points_pushed++); \
1313 DEBUG_PRINT2 ("\nPUSH_FAILURE_POINT #%u:\n", failure_id); \
1314 DEBUG_PRINT2 (" Before push, next avail: %d\n", (fail_stack).avail);\
1315 DEBUG_PRINT2 (" size: %d\n", (fail_stack).size);\
1316 \
1317 DEBUG_PRINT2 (" slots needed: %ld\n", NUM_FAILURE_ITEMS); \
1318 DEBUG_PRINT2 (" available: %d\n", REMAINING_AVAIL_SLOTS); \
1319 \
1320 /* Ensure we have enough space allocated for what we will push. */ \
1321 while (REMAINING_AVAIL_SLOTS < NUM_FAILURE_ITEMS) \
1322 { \
1323 if (!DOUBLE_FAIL_STACK (fail_stack)) \
1324 return failure_code; \
1325 \
1326 DEBUG_PRINT2 ("\n Doubled stack; size now: %d\n", \
1327 (fail_stack).size); \
1328 DEBUG_PRINT2 (" slots available: %d\n", REMAINING_AVAIL_SLOTS);\
1329 } \
1330 \
1331 /* Push the info, starting with the registers. */ \
1332 DEBUG_PRINT1 ("\n"); \
1333 \
1334 if (1) \
1335 for (this_reg = lowest_active_reg; this_reg <= highest_active_reg; \
1336 this_reg++) \
1337 { \
1338 DEBUG_PRINT2 (" Pushing reg: %lu\n", this_reg); \
1339 DEBUG_STATEMENT (num_regs_pushed++); \
1340 \
1341 DEBUG_PRINT2 (" start: %p\n", regstart[this_reg]); \
1342 PUSH_FAILURE_POINTER (regstart[this_reg]); \
1343 \
1344 DEBUG_PRINT2 (" end: %p\n", regend[this_reg]); \
1345 PUSH_FAILURE_POINTER (regend[this_reg]); \
1346 \
1347 DEBUG_PRINT2 (" info: %p\n ", \
1348 reg_info[this_reg].word.pointer); \
1349 DEBUG_PRINT2 (" match_null=%d", \
1350 REG_MATCH_NULL_STRING_P (reg_info[this_reg])); \
1351 DEBUG_PRINT2 (" active=%d", IS_ACTIVE (reg_info[this_reg])); \
1352 DEBUG_PRINT2 (" matched_something=%d", \
1353 MATCHED_SOMETHING (reg_info[this_reg])); \
1354 DEBUG_PRINT2 (" ever_matched=%d", \
1355 EVER_MATCHED_SOMETHING (reg_info[this_reg])); \
1356 DEBUG_PRINT1 ("\n"); \
1357 PUSH_FAILURE_ELT (reg_info[this_reg].word); \
1358 } \
1359 \
1360 DEBUG_PRINT2 (" Pushing low active reg: %ld\n", lowest_active_reg);\
1361 PUSH_FAILURE_INT (lowest_active_reg); \
1362 \
1363 DEBUG_PRINT2 (" Pushing high active reg: %ld\n", highest_active_reg);\
1364 PUSH_FAILURE_INT (highest_active_reg); \
1365 \
1366 DEBUG_PRINT2 (" Pushing pattern %p:\n", pattern_place); \
1367 DEBUG_PRINT_COMPILED_PATTERN (bufp, pattern_place, pend); \
1368 PUSH_FAILURE_POINTER (pattern_place); \
1369 \
1370 DEBUG_PRINT2 (" Pushing string %p: `", string_place); \
1371 DEBUG_PRINT_DOUBLE_STRING (string_place, string1, size1, string2, \
1372 size2); \
1373 DEBUG_PRINT1 ("'\n"); \
1374 PUSH_FAILURE_POINTER (string_place); \
1375 \
1376 DEBUG_PRINT2 (" Pushing failure id: %u\n", failure_id); \
1377 DEBUG_PUSH (failure_id); \
1378 } while (0)
1379
1380 /* This is the number of items that are pushed and popped on the stack
1381 for each register. */
1382 #define NUM_REG_ITEMS 3
1383
1384 /* Individual items aside from the registers. */
1385 #ifdef DEBUG
1386 # define NUM_NONREG_ITEMS 5 /* Includes failure point id. */
1387 #else
1388 # define NUM_NONREG_ITEMS 4
1389 #endif
1390
1391 /* We push at most this many items on the stack. */
1392 /* We used to use (num_regs - 1), which is the number of registers
1393 this regexp will save; but that was changed to 5
1394 to avoid stack overflow for a regexp with lots of parens. */
1395 #define MAX_FAILURE_ITEMS (5 * NUM_REG_ITEMS + NUM_NONREG_ITEMS)
1396
1397 /* We actually push this many items. */
1398 #define NUM_FAILURE_ITEMS \
1399 (((0 \
1400 ? 0 : highest_active_reg - lowest_active_reg + 1) \
1401 * NUM_REG_ITEMS) \
1402 + NUM_NONREG_ITEMS)
1403
1404 /* How many items can still be added to the stack without overflowing it. */
1405 #define REMAINING_AVAIL_SLOTS ((fail_stack).size - (fail_stack).avail)
1406
1407
1408 /* Pops what PUSH_FAIL_STACK pushes.
1409
1410 We restore into the parameters, all of which should be lvalues:
1411 STR -- the saved data position.
1412 PAT -- the saved pattern position.
1413 LOW_REG, HIGH_REG -- the highest and lowest active registers.
1414 REGSTART, REGEND -- arrays of string positions.
1415 REG_INFO -- array of information about each subexpression.
1416
1417 Also assumes the variables `fail_stack' and (if debugging), `bufp',
1418 `pend', `string1', `size1', `string2', and `size2'. */
1419
1420 #define POP_FAILURE_POINT(str, pat, low_reg, high_reg, regstart, regend, reg_info)\
1421 { \
1422 DEBUG_STATEMENT (unsigned failure_id;) \
1423 active_reg_t this_reg; \
1424 const unsigned char *string_temp; \
1425 \
1426 assert (!FAIL_STACK_EMPTY ()); \
1427 \
1428 /* Remove failure points and point to how many regs pushed. */ \
1429 DEBUG_PRINT1 ("POP_FAILURE_POINT:\n"); \
1430 DEBUG_PRINT2 (" Before pop, next avail: %d\n", fail_stack.avail); \
1431 DEBUG_PRINT2 (" size: %d\n", fail_stack.size); \
1432 \
1433 assert (fail_stack.avail >= NUM_NONREG_ITEMS); \
1434 \
1435 DEBUG_POP (&failure_id); \
1436 DEBUG_PRINT2 (" Popping failure id: %u\n", failure_id); \
1437 \
1438 /* If the saved string location is NULL, it came from an \
1439 on_failure_keep_string_jump opcode, and we want to throw away the \
1440 saved NULL, thus retaining our current position in the string. */ \
1441 string_temp = POP_FAILURE_POINTER (); \
1442 if (string_temp != NULL) \
1443 str = (const char *) string_temp; \
1444 \
1445 DEBUG_PRINT2 (" Popping string %p: `", str); \
1446 DEBUG_PRINT_DOUBLE_STRING (str, string1, size1, string2, size2); \
1447 DEBUG_PRINT1 ("'\n"); \
1448 \
1449 pat = (unsigned char *) POP_FAILURE_POINTER (); \
1450 DEBUG_PRINT2 (" Popping pattern %p:\n", pat); \
1451 DEBUG_PRINT_COMPILED_PATTERN (bufp, pat, pend); \
1452 \
1453 /* Restore register info. */ \
1454 high_reg = (active_reg_t) POP_FAILURE_INT (); \
1455 DEBUG_PRINT2 (" Popping high active reg: %ld\n", high_reg); \
1456 \
1457 low_reg = (active_reg_t) POP_FAILURE_INT (); \
1458 DEBUG_PRINT2 (" Popping low active reg: %ld\n", low_reg); \
1459 \
1460 if (1) \
1461 for (this_reg = high_reg; this_reg >= low_reg; this_reg--) \
1462 { \
1463 DEBUG_PRINT2 (" Popping reg: %ld\n", this_reg); \
1464 \
1465 reg_info[this_reg].word = POP_FAILURE_ELT (); \
1466 DEBUG_PRINT2 (" info: %p\n", \
1467 reg_info[this_reg].word.pointer); \
1468 \
1469 regend[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1470 DEBUG_PRINT2 (" end: %p\n", regend[this_reg]); \
1471 \
1472 regstart[this_reg] = (const char *) POP_FAILURE_POINTER (); \
1473 DEBUG_PRINT2 (" start: %p\n", regstart[this_reg]); \
1474 } \
1475 else \
1476 { \
1477 for (this_reg = highest_active_reg; this_reg > high_reg; this_reg--) \
1478 { \
1479 reg_info[this_reg].word.integer = 0; \
1480 regend[this_reg] = 0; \
1481 regstart[this_reg] = 0; \
1482 } \
1483 highest_active_reg = high_reg; \
1484 } \
1485 \
1486 set_regs_matched_done = 0; \
1487 DEBUG_STATEMENT (nfailure_points_popped++); \
1488 } /* POP_FAILURE_POINT */
1489
1490
1491
1492 /* Structure for per-register (a.k.a. per-group) information.
1493 Other register information, such as the
1494 starting and ending positions (which are addresses), and the list of
1495 inner groups (which is a bits list) are maintained in separate
1496 variables.
1497
1498 We are making a (strictly speaking) nonportable assumption here: that
1499 the compiler will pack our bit fields into something that fits into
1500 the type of `word', i.e., is something that fits into one item on the
1501 failure stack. */
1502
1503
1504 /* Declarations and macros for re_match_2. */
1505
1506 typedef union
1507 {
1508 fail_stack_elt_t word;
1509 struct
1510 {
1511 /* This field is one if this group can match the empty string,
1512 zero if not. If not yet determined, `MATCH_NULL_UNSET_VALUE'. */
1513 #define MATCH_NULL_UNSET_VALUE 3
1514 unsigned match_null_string_p : 2;
1515 unsigned is_active : 1;
1516 unsigned matched_something : 1;
1517 unsigned ever_matched_something : 1;
1518 } bits;
1519 } register_info_type;
1520
1521 #define REG_MATCH_NULL_STRING_P(R) ((R).bits.match_null_string_p)
1522 #define IS_ACTIVE(R) ((R).bits.is_active)
1523 #define MATCHED_SOMETHING(R) ((R).bits.matched_something)
1524 #define EVER_MATCHED_SOMETHING(R) ((R).bits.ever_matched_something)
1525
1526
1527 /* Call this when have matched a real character; it sets `matched' flags
1528 for the subexpressions which we are currently inside. Also records
1529 that those subexprs have matched. */
1530 #define SET_REGS_MATCHED() \
1531 do \
1532 { \
1533 if (!set_regs_matched_done) \
1534 { \
1535 active_reg_t r; \
1536 set_regs_matched_done = 1; \
1537 for (r = lowest_active_reg; r <= highest_active_reg; r++) \
1538 { \
1539 MATCHED_SOMETHING (reg_info[r]) \
1540 = EVER_MATCHED_SOMETHING (reg_info[r]) \
1541 = 1; \
1542 } \
1543 } \
1544 } \
1545 while (0)
1546
1547 /* Registers are set to a sentinel when they haven't yet matched. */
1548 static char reg_unset_dummy;
1549 #define REG_UNSET_VALUE (®_unset_dummy)
1550 #define REG_UNSET(e) ((e) == REG_UNSET_VALUE)
1551
1552 /* Subroutine declarations and macros for regex_compile. */
1553
1554 static reg_errcode_t regex_compile _RE_ARGS ((const char *pattern, size_t size,
1555 reg_syntax_t syntax,
1556 struct re_pattern_buffer *bufp));
1557 static void store_op1 _RE_ARGS ((re_opcode_t op, unsigned char *loc, int arg));
1558 static void store_op2 _RE_ARGS ((re_opcode_t op, unsigned char *loc,
1559 int arg1, int arg2));
1560 static void insert_op1 _RE_ARGS ((re_opcode_t op, unsigned char *loc,
1561 int arg, unsigned char *end));
1562 static void insert_op2 _RE_ARGS ((re_opcode_t op, unsigned char *loc,
1563 int arg1, int arg2, unsigned char *end));
1564 static boolean at_begline_loc_p _RE_ARGS ((const char *pattern, const char *p,
1565 reg_syntax_t syntax));
1566 static boolean at_endline_loc_p _RE_ARGS ((const char *p, const char *pend,
1567 reg_syntax_t syntax));
1568 static reg_errcode_t compile_range _RE_ARGS ((const char **p_ptr,
1569 const char *pend,
1570 char *translate,
1571 reg_syntax_t syntax,
1572 unsigned char *b));
1573
1574 /* Fetch the next character in the uncompiled pattern---translating it
1575 if necessary. Also cast from a signed character in the constant
1576 string passed to us by the user to an unsigned char that we can use
1577 as an array index (in, e.g., `translate'). */
1578 #ifndef PATFETCH
1579 # define PATFETCH(c) \
1580 do {if (p == pend) return REG_EEND; \
1581 c = (unsigned char) *p++; \
1582 if (translate) c = (unsigned char) translate[c]; \
1583 } while (0)
1584 #endif
1585
1586 /* Fetch the next character in the uncompiled pattern, with no
1587 translation. */
1588 #define PATFETCH_RAW(c) \
1589 do {if (p == pend) return REG_EEND; \
1590 c = (unsigned char) *p++; \
1591 } while (0)
1592
1593 /* Go backwards one character in the pattern. */
1594 #define PATUNFETCH p--
1595
1596
1597 /* If `translate' is non-null, return translate[D], else just D. We
1598 cast the subscript to translate because some data is declared as
1599 `char *', to avoid warnings when a string constant is passed. But
1600 when we use a character as a subscript we must make it unsigned. */
1601 #ifndef TRANSLATE
1602 # define TRANSLATE(d) \
1603 (translate ? (char) translate[(unsigned char) (d)] : (d))
1604 #endif
1605
1606
1607 /* Macros for outputting the compiled pattern into `buffer'. */
1608
1609 /* If the buffer isn't allocated when it comes in, use this. */
1610 #define INIT_BUF_SIZE 32
1611
1612 /* Make sure we have at least N more bytes of space in buffer. */
1613 #define GET_BUFFER_SPACE(n) \
1614 while ((unsigned long) (b - bufp->buffer + (n)) > bufp->allocated) \
1615 EXTEND_BUFFER ()
1616
1617 /* Make sure we have one more byte of buffer space and then add C to it. */
1618 #define BUF_PUSH(c) \
1619 do { \
1620 GET_BUFFER_SPACE (1); \
1621 *b++ = (unsigned char) (c); \
1622 } while (0)
1623
1624
1625 /* Ensure we have two more bytes of buffer space and then append C1 and C2. */
1626 #define BUF_PUSH_2(c1, c2) \
1627 do { \
1628 GET_BUFFER_SPACE (2); \
1629 *b++ = (unsigned char) (c1); \
1630 *b++ = (unsigned char) (c2); \
1631 } while (0)
1632
1633
1634 /* As with BUF_PUSH_2, except for three bytes. */
1635 #define BUF_PUSH_3(c1, c2, c3) \
1636 do { \
1637 GET_BUFFER_SPACE (3); \
1638 *b++ = (unsigned char) (c1); \
1639 *b++ = (unsigned char) (c2); \
1640 *b++ = (unsigned char) (c3); \
1641 } while (0)
1642
1643
1644 /* Store a jump with opcode OP at LOC to location TO. We store a
1645 relative address offset by the three bytes the jump itself occupies. */
1646 #define STORE_JUMP(op, loc, to) \
1647 store_op1 (op, loc, (int) ((to) - (loc) - 3))
1648
1649 /* Likewise, for a two-argument jump. */
1650 #define STORE_JUMP2(op, loc, to, arg) \
1651 store_op2 (op, loc, (int) ((to) - (loc) - 3), arg)
1652
1653 /* Like `STORE_JUMP', but for inserting. Assume `b' is the buffer end. */
1654 #define INSERT_JUMP(op, loc, to) \
1655 insert_op1 (op, loc, (int) ((to) - (loc) - 3), b)
1656
1657 /* Like `STORE_JUMP2', but for inserting. Assume `b' is the buffer end. */
1658 #define INSERT_JUMP2(op, loc, to, arg) \
1659 insert_op2 (op, loc, (int) ((to) - (loc) - 3), arg, b)
1660
1661
1662 /* This is not an arbitrary limit: the arguments which represent offsets
1663 into the pattern are two bytes long. So if 2^16 bytes turns out to
1664 be too small, many things would have to change. */
1665 /* Any other compiler which, like MSC, has allocation limit below 2^16
1666 bytes will have to use approach similar to what was done below for
1667 MSC and drop MAX_BUF_SIZE a bit. Otherwise you may end up
1668 reallocating to 0 bytes. Such thing is not going to work too well.
1669 You have been warned!! */
1670 #if defined _MSC_VER && !defined WIN32
1671 /* Microsoft C 16-bit versions limit malloc to approx 65512 bytes.
1672 The REALLOC define eliminates a flurry of conversion warnings,
1673 but is not required. */
1674 # define MAX_BUF_SIZE 65500L
1675 # define REALLOC(p,s) realloc ((p), (size_t) (s))
1676 #else
1677 # define MAX_BUF_SIZE (1L << 16)
1678 # define REALLOC(p,s) realloc ((p), (s))
1679 #endif
1680
1681 /* Extend the buffer by twice its current size via realloc and
1682 reset the pointers that pointed into the old block to point to the
1683 correct places in the new one. If extending the buffer results in it
1684 being larger than MAX_BUF_SIZE, then flag memory exhausted. */
1685 #define EXTEND_BUFFER() \
1686 do { \
1687 unsigned char *old_buffer = bufp->buffer; \
1688 if (bufp->allocated == MAX_BUF_SIZE) \
1689 return REG_ESIZE; \
1690 bufp->allocated <<= 1; \
1691 if (bufp->allocated > MAX_BUF_SIZE) \
1692 bufp->allocated = MAX_BUF_SIZE; \
1693 bufp->buffer = (unsigned char *) REALLOC (bufp->buffer, bufp->allocated);\
1694 if (bufp->buffer == NULL) \
1695 return REG_ESPACE; \
1696 /* If the buffer moved, move all the pointers into it. */ \
1697 if (old_buffer != bufp->buffer) \
1698 { \
1699 b = (b - old_buffer) + bufp->buffer; \
1700 begalt = (begalt - old_buffer) + bufp->buffer; \
1701 if (fixup_alt_jump) \
1702 fixup_alt_jump = (fixup_alt_jump - old_buffer) + bufp->buffer;\
1703 if (laststart) \
1704 laststart = (laststart - old_buffer) + bufp->buffer; \
1705 if (pending_exact) \
1706 pending_exact = (pending_exact - old_buffer) + bufp->buffer; \
1707 } \
1708 } while (0)
1709
1710
1711 /* Since we have one byte reserved for the register number argument to
1712 {start,stop}_memory, the maximum number of groups we can report
1713 things about is what fits in that byte. */
1714 #define MAX_REGNUM 255
1715
1716 /* But patterns can have more than `MAX_REGNUM' registers. We just
1717 ignore the excess. */
1718 typedef unsigned regnum_t;
1719
1720
1721 /* Macros for the compile stack. */
1722
1723 /* Since offsets can go either forwards or backwards, this type needs to
1724 be able to hold values from -(MAX_BUF_SIZE - 1) to MAX_BUF_SIZE - 1. */
1725 /* int may be not enough when sizeof(int) == 2. */
1726 typedef long pattern_offset_t;
1727
1728 typedef struct
1729 {
1730 pattern_offset_t begalt_offset;
1731 pattern_offset_t fixup_alt_jump;
1732 pattern_offset_t inner_group_offset;
1733 pattern_offset_t laststart_offset;
1734 regnum_t regnum;
1735 } compile_stack_elt_t;
1736
1737
1738 typedef struct
1739 {
1740 compile_stack_elt_t *stack;
1741 unsigned size;
1742 unsigned avail; /* Offset of next open position. */
1743 } compile_stack_type;
1744
1745
1746 #define INIT_COMPILE_STACK_SIZE 32
1747
1748 #define COMPILE_STACK_EMPTY (compile_stack.avail == 0)
1749 #define COMPILE_STACK_FULL (compile_stack.avail == compile_stack.size)
1750
1751 /* The next available element. */
1752 #define COMPILE_STACK_TOP (compile_stack.stack[compile_stack.avail])
1753
1754
1755 /* Set the bit for character C in a list. */
1756 #define SET_LIST_BIT(c) \
1757 (b[((unsigned char) (c)) / BYTEWIDTH] \
1758 |= 1 << (((unsigned char) c) % BYTEWIDTH))
1759
1760
1761 /* Get the next unsigned number in the uncompiled pattern. */
1762 #define GET_UNSIGNED_NUMBER(num) \
1763 { if (p != pend) \
1764 { \
1765 PATFETCH (c); \
1766 while ('0' <= c && c <= '9') \
1767 { \
1768 if (num < 0) \
1769 num = 0; \
1770 num = num * 10 + c - '0'; \
1771 if (p == pend) \
1772 break; \
1773 PATFETCH (c); \
1774 } \
1775 } \
1776 }
1777
1778 #if defined _LIBC || WIDE_CHAR_SUPPORT
1779 /* The GNU C library provides support for user-defined character classes
1780 and the functions from ISO C amendement 1. */
1781 # ifdef CHARCLASS_NAME_MAX
1782 # define CHAR_CLASS_MAX_LENGTH CHARCLASS_NAME_MAX
1783 # else
1784 /* This shouldn't happen but some implementation might still have this
1785 problem. Use a reasonable default value. */
1786 # define CHAR_CLASS_MAX_LENGTH 256
1787 # endif
1788
1789 # ifdef _LIBC
1790 # define IS_CHAR_CLASS(string) __wctype (string)
1791 # else
1792 # define IS_CHAR_CLASS(string) wctype (string)
1793 # endif
1794 #else
1795 # define CHAR_CLASS_MAX_LENGTH 6 /* Namely, `xdigit'. */
1796
1797 # define IS_CHAR_CLASS(string) \
1798 (STREQ (string, "alpha") || STREQ (string, "upper") \
1799 || STREQ (string, "lower") || STREQ (string, "digit") \
1800 || STREQ (string, "alnum") || STREQ (string, "xdigit") \
1801 || STREQ (string, "space") || STREQ (string, "print") \
1802 || STREQ (string, "punct") || STREQ (string, "graph") \
1803 || STREQ (string, "cntrl") || STREQ (string, "blank"))
1804 #endif
1805
1806 #ifndef MATCH_MAY_ALLOCATE
1807
1808 /* If we cannot allocate large objects within re_match_2_internal,
1809 we make the fail stack and register vectors global.
1810 The fail stack, we grow to the maximum size when a regexp
1811 is compiled.
1812 The register vectors, we adjust in size each time we
1813 compile a regexp, according to the number of registers it needs. */
1814
1815 static fail_stack_type fail_stack;
1816
1817 /* Size with which the following vectors are currently allocated.
1818 That is so we can make them bigger as needed,
1819 but never make them smaller. */
1820 static int regs_allocated_size;
1821
1822 static const char ** regstart, ** regend;
1823 static const char ** old_regstart, ** old_regend;
1824 static const char **best_regstart, **best_regend;
1825 static register_info_type *reg_info;
1826 static const char **reg_dummy;
1827 static register_info_type *reg_info_dummy;
1828
1829 /* Make the register vectors big enough for NUM_REGS registers,
1830 but don't make them smaller. */
1831
1832 static
1833 regex_grow_registers (num_regs)
1834 int num_regs;
1835 {
1836 if (num_regs > regs_allocated_size)
1837 {
1838 RETALLOC_IF (regstart, num_regs, const char *);
1839 RETALLOC_IF (regend, num_regs, const char *);
1840 RETALLOC_IF (old_regstart, num_regs, const char *);
1841 RETALLOC_IF (old_regend, num_regs, const char *);
1842 RETALLOC_IF (best_regstart, num_regs, const char *);
1843 RETALLOC_IF (best_regend, num_regs, const char *);
1844 RETALLOC_IF (reg_info, num_regs, register_info_type);
1845 RETALLOC_IF (reg_dummy, num_regs, const char *);
1846 RETALLOC_IF (reg_info_dummy, num_regs, register_info_type);
1847
1848 regs_allocated_size = num_regs;
1849 }
1850 }
1851
1852 #endif /* not MATCH_MAY_ALLOCATE */
1853
1854 static boolean group_in_compile_stack _RE_ARGS ((compile_stack_type
1855 compile_stack,
1856 regnum_t regnum));
1857
1858 /* `regex_compile' compiles PATTERN (of length SIZE) according to SYNTAX.
1859 Returns one of error codes defined in `regex.h', or zero for success.
1860
1861 Assumes the `allocated' (and perhaps `buffer') and `translate'
1862 fields are set in BUFP on entry.
1863
1864 If it succeeds, results are put in BUFP (if it returns an error, the
1865 contents of BUFP are undefined):
1866 `buffer' is the compiled pattern;
1867 `syntax' is set to SYNTAX;
1868 `used' is set to the length of the compiled pattern;
1869 `fastmap_accurate' is zero;
1870 `re_nsub' is the number of subexpressions in PATTERN;
1871 `not_bol' and `not_eol' are zero;
1872
1873 The `fastmap' and `newline_anchor' fields are neither
1874 examined nor set. */
1875
1876 /* Return, freeing storage we allocated. */
1877 #define FREE_STACK_RETURN(value) \
1878 return (free (compile_stack.stack), value)
1879
1880 static reg_errcode_t
1881 regex_compile (pattern, size, syntax, bufp)
1882 const char *pattern;
1883 size_t size;
1884 reg_syntax_t syntax;
1885 struct re_pattern_buffer *bufp;
1886 {
1887 /* We fetch characters from PATTERN here. Even though PATTERN is
1888 `char *' (i.e., signed), we declare these variables as unsigned, so
1889 they can be reliably used as array indices. */
1890 register unsigned char c, c1;
1891
1892 /* A random temporary spot in PATTERN. */
1893 const char *p1;
1894
1895 /* Points to the end of the buffer, where we should append. */
1896 register unsigned char *b;
1897
1898 /* Keeps track of unclosed groups. */
1899 compile_stack_type compile_stack;
1900
1901 /* Points to the current (ending) position in the pattern. */
1902 const char *p = pattern;
1903 const char *pend = pattern + size;
1904
1905 /* How to translate the characters in the pattern. */
1906 RE_TRANSLATE_TYPE translate = bufp->translate;
1907
1908 /* Address of the count-byte of the most recently inserted `exactn'
1909 command. This makes it possible to tell if a new exact-match
1910 character can be added to that command or if the character requires
1911 a new `exactn' command. */
1912 unsigned char *pending_exact = 0;
1913
1914 /* Address of start of the most recently finished expression.
1915 This tells, e.g., postfix * where to find the start of its
1916 operand. Reset at the beginning of groups and alternatives. */
1917 unsigned char *laststart = 0;
1918
1919 /* Address of beginning of regexp, or inside of last group. */
1920 unsigned char *begalt;
1921
1922 /* Place in the uncompiled pattern (i.e., the {) to
1923 which to go back if the interval is invalid. */
1924 const char *beg_interval;
1925
1926 /* Address of the place where a forward jump should go to the end of
1927 the containing expression. Each alternative of an `or' -- except the
1928 last -- ends with a forward jump of this sort. */
1929 unsigned char *fixup_alt_jump = 0;
1930
1931 /* Counts open-groups as they are encountered. Remembered for the
1932 matching close-group on the compile stack, so the same register
1933 number is put in the stop_memory as the start_memory. */
1934 regnum_t regnum = 0;
1935
1936 #ifdef DEBUG
1937 DEBUG_PRINT1 ("\nCompiling pattern: ");
1938 if (debug)
1939 {
1940 unsigned debug_count;
1941
1942 for (debug_count = 0; debug_count < size; debug_count++)
1943 putchar (pattern[debug_count]);
1944 putchar ('\n');
1945 }
1946 #endif /* DEBUG */
1947
1948 /* Initialize the compile stack. */
1949 compile_stack.stack = TALLOC (INIT_COMPILE_STACK_SIZE, compile_stack_elt_t);
1950 if (compile_stack.stack == NULL)
1951 return REG_ESPACE;
1952
1953 compile_stack.size = INIT_COMPILE_STACK_SIZE;
1954 compile_stack.avail = 0;
1955
1956 /* Initialize the pattern buffer. */
1957 bufp->syntax = syntax;
1958 bufp->fastmap_accurate = 0;
1959 bufp->not_bol = bufp->not_eol = 0;
1960
1961 /* Set `used' to zero, so that if we return an error, the pattern
1962 printer (for debugging) will think there's no pattern. We reset it
1963 at the end. */
1964 bufp->used = 0;
1965
1966 /* Always count groups, whether or not bufp->no_sub is set. */
1967 bufp->re_nsub = 0;
1968
1969 #if !defined emacs && !defined SYNTAX_TABLE
1970 /* Initialize the syntax table. */
1971 init_syntax_once ();
1972 #endif
1973
1974 if (bufp->allocated == 0)
1975 {
1976 if (bufp->buffer)
1977 { /* If zero allocated, but buffer is non-null, try to realloc
1978 enough space. This loses if buffer's address is bogus, but
1979 that is the user's responsibility. */
1980 RETALLOC (bufp->buffer, INIT_BUF_SIZE, unsigned char);
1981 }
1982 else
1983 { /* Caller did not allocate a buffer. Do it for them. */
1984 bufp->buffer = TALLOC (INIT_BUF_SIZE, unsigned char);
1985 }
1986 if (!bufp->buffer) FREE_STACK_RETURN (REG_ESPACE);
1987
1988 bufp->allocated = INIT_BUF_SIZE;
1989 }
1990
1991 begalt = b = bufp->buffer;
1992
1993 /* Loop through the uncompiled pattern until we're at the end. */
1994 while (p != pend)
1995 {
1996 PATFETCH (c);
1997
1998 switch (c)
1999 {
2000 case '^':
2001 {
2002 if ( /* If at start of pattern, it's an operator. */
2003 p == pattern + 1
2004 /* If context independent, it's an operator. */
2005 || syntax & RE_CONTEXT_INDEP_ANCHORS
2006 /* Otherwise, depends on what's come before. */
2007 || at_begline_loc_p (pattern, p, syntax))
2008 BUF_PUSH (begline);
2009 else
2010 goto normal_char;
2011 }
2012 break;
2013
2014
2015 case '$':
2016 {
2017 if ( /* If at end of pattern, it's an operator. */
2018 p == pend
2019 /* If context independent, it's an operator. */
2020 || syntax & RE_CONTEXT_INDEP_ANCHORS
2021 /* Otherwise, depends on what's next. */
2022 || at_endline_loc_p (p, pend, syntax))
2023 BUF_PUSH (endline);
2024 else
2025 goto normal_char;
2026 }
2027 break;
2028
2029
2030 case '+':
2031 case '?':
2032 if ((syntax & RE_BK_PLUS_QM)
2033 || (syntax & RE_LIMITED_OPS))
2034 goto normal_char;
2035 handle_plus:
2036 case '*':
2037 /* If there is no previous pattern... */
2038 if (!laststart)
2039 {
2040 if (syntax & RE_CONTEXT_INVALID_OPS)
2041 FREE_STACK_RETURN (REG_BADRPT);
2042 else if (!(syntax & RE_CONTEXT_INDEP_OPS))
2043 goto normal_char;
2044 }
2045
2046 {
2047 /* Are we optimizing this jump? */
2048 boolean keep_string_p = false;
2049
2050 /* 1 means zero (many) matches is allowed. */
2051 char zero_times_ok = 0, many_times_ok = 0;
2052
2053 /* If there is a sequence of repetition chars, collapse it
2054 down to just one (the right one). We can't combine
2055 interval operators with these because of, e.g., `a{2}*',
2056 which should only match an even number of `a's. */
2057
2058 for (;;)
2059 {
2060 zero_times_ok |= c != '+';
2061 many_times_ok |= c != '?';
2062
2063 if (p == pend)
2064 break;
2065
2066 PATFETCH (c);
2067
2068 if (c == '*'
2069 || (!(syntax & RE_BK_PLUS_QM) && (c == '+' || c == '?')))
2070 ;
2071
2072 else if (syntax & RE_BK_PLUS_QM && c == '\\')
2073 {
2074 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2075
2076 PATFETCH (c1);
2077 if (!(c1 == '+' || c1 == '?'))
2078 {
2079 PATUNFETCH;
2080 PATUNFETCH;
2081 break;
2082 }
2083
2084 c = c1;
2085 }
2086 else
2087 {
2088 PATUNFETCH;
2089 break;
2090 }
2091
2092 /* If we get here, we found another repeat character. */
2093 }
2094
2095 /* Star, etc. applied to an empty pattern is equivalent
2096 to an empty pattern. */
2097 if (!laststart)
2098 break;
2099
2100 /* Now we know whether or not zero matches is allowed
2101 and also whether or not two or more matches is allowed. */
2102 if (many_times_ok)
2103 { /* More than one repetition is allowed, so put in at the
2104 end a backward relative jump from `b' to before the next
2105 jump we're going to put in below (which jumps from
2106 laststart to after this jump).
2107
2108 But if we are at the `*' in the exact sequence `.*\n',
2109 insert an unconditional jump backwards to the .,
2110 instead of the beginning of the loop. This way we only
2111 push a failure point once, instead of every time
2112 through the loop. */
2113 assert (p - 1 > pattern);
2114
2115 /* Allocate the space for the jump. */
2116 GET_BUFFER_SPACE (3);
2117
2118 /* We know we are not at the first character of the pattern,
2119 because laststart was nonzero. And we've already
2120 incremented `p', by the way, to be the character after
2121 the `*'. Do we have to do something analogous here
2122 for null bytes, because of RE_DOT_NOT_NULL? */
2123 if (TRANSLATE (*(p - 2)) == TRANSLATE ('.')
2124 && zero_times_ok
2125 && p < pend && TRANSLATE (*p) == TRANSLATE ('\n')
2126 && !(syntax & RE_DOT_NEWLINE))
2127 { /* We have .*\n. */
2128 STORE_JUMP (jump, b, laststart);
2129 keep_string_p = true;
2130 }
2131 else
2132 /* Anything else. */
2133 STORE_JUMP (maybe_pop_jump, b, laststart - 3);
2134
2135 /* We've added more stuff to the buffer. */
2136 b += 3;
2137 }
2138
2139 /* On failure, jump from laststart to b + 3, which will be the
2140 end of the buffer after this jump is inserted. */
2141 GET_BUFFER_SPACE (3);
2142 INSERT_JUMP (keep_string_p ? on_failure_keep_string_jump
2143 : on_failure_jump,
2144 laststart, b + 3);
2145 pending_exact = 0;
2146 b += 3;
2147
2148 if (!zero_times_ok)
2149 {
2150 /* At least one repetition is required, so insert a
2151 `dummy_failure_jump' before the initial
2152 `on_failure_jump' instruction of the loop. This
2153 effects a skip over that instruction the first time
2154 we hit that loop. */
2155 GET_BUFFER_SPACE (3);
2156 INSERT_JUMP (dummy_failure_jump, laststart, laststart + 6);
2157 b += 3;
2158 }
2159 }
2160 break;
2161
2162
2163 case '.':
2164 laststart = b;
2165 BUF_PUSH (anychar);
2166 break;
2167
2168
2169 case '[':
2170 {
2171 boolean had_char_class = false;
2172
2173 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2174
2175 /* Ensure that we have enough space to push a charset: the
2176 opcode, the length count, and the bitset; 34 bytes in all. */
2177 GET_BUFFER_SPACE (34);
2178
2179 laststart = b;
2180
2181 /* We test `*p == '^' twice, instead of using an if
2182 statement, so we only need one BUF_PUSH. */
2183 BUF_PUSH (*p == '^' ? charset_not : charset);
2184 if (*p == '^')
2185 p++;
2186
2187 /* Remember the first position in the bracket expression. */
2188 p1 = p;
2189
2190 /* Push the number of bytes in the bitmap. */
2191 BUF_PUSH ((1 << BYTEWIDTH) / BYTEWIDTH);
2192
2193 /* Clear the whole map. */
2194 bzero (b, (1 << BYTEWIDTH) / BYTEWIDTH);
2195
2196 /* charset_not matches newline according to a syntax bit. */
2197 if ((re_opcode_t) b[-2] == charset_not
2198 && (syntax & RE_HAT_LISTS_NOT_NEWLINE))
2199 SET_LIST_BIT ('\n');
2200
2201 /* Read in characters and ranges, setting map bits. */
2202 for (;;)
2203 {
2204 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2205
2206 PATFETCH (c);
2207
2208 /* \ might escape characters inside [...] and [^...]. */
2209 if ((syntax & RE_BACKSLASH_ESCAPE_IN_LISTS) && c == '\\')
2210 {
2211 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2212
2213 PATFETCH (c1);
2214 SET_LIST_BIT (c1);
2215 continue;
2216 }
2217
2218 /* Could be the end of the bracket expression. If it's
2219 not (i.e., when the bracket expression is `[]' so
2220 far), the ']' character bit gets set way below. */
2221 if (c == ']' && p != p1 + 1)
2222 break;
2223
2224 /* Look ahead to see if it's a range when the last thing
2225 was a character class. */
2226 if (had_char_class && c == '-' && *p != ']')
2227 FREE_STACK_RETURN (REG_ERANGE);
2228
2229 /* Look ahead to see if it's a range when the last thing
2230 was a character: if this is a hyphen not at the
2231 beginning or the end of a list, then it's the range
2232 operator. */
2233 if (c == '-'
2234 && !(p - 2 >= pattern && p[-2] == '[')
2235 && !(p - 3 >= pattern && p[-3] == '[' && p[-2] == '^')
2236 && *p != ']')
2237 {
2238 reg_errcode_t ret
2239 = compile_range (&p, pend, translate, syntax, b);
2240 if (ret != REG_NOERROR) FREE_STACK_RETURN (ret);
2241 }
2242
2243 else if (p[0] == '-' && p[1] != ']')
2244 { /* This handles ranges made up of characters only. */
2245 reg_errcode_t ret;
2246
2247 /* Move past the `-'. */
2248 PATFETCH (c1);
2249
2250 ret = compile_range (&p, pend, translate, syntax, b);
2251 if (ret != REG_NOERROR) FREE_STACK_RETURN (ret);
2252 }
2253
2254 /* See if we're at the beginning of a possible character
2255 class. */
2256
2257 else if (syntax & RE_CHAR_CLASSES && c == '[' && *p == ':')
2258 { /* Leave room for the null. */
2259 char str[CHAR_CLASS_MAX_LENGTH + 1];
2260
2261 PATFETCH (c);
2262 c1 = 0;
2263
2264 /* If pattern is `[[:'. */
2265 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2266
2267 for (;;)
2268 {
2269 PATFETCH (c);
2270 if ((c == ':' && *p == ']') || p == pend)
2271 break;
2272 if (c1 < CHAR_CLASS_MAX_LENGTH)
2273 str[c1++] = c;
2274 else
2275 /* This is in any case an invalid class name. */
2276 str[0] = '\0';
2277 }
2278 str[c1] = '\0';
2279
2280 /* If isn't a word bracketed by `[:' and `:]':
2281 undo the ending character, the letters, and leave
2282 the leading `:' and `[' (but set bits for them). */
2283 if (c == ':' && *p == ']')
2284 {
2285 #if defined _LIBC || WIDE_CHAR_SUPPORT
2286 boolean is_lower = STREQ (str, "lower");
2287 boolean is_upper = STREQ (str, "upper");
2288 wctype_t wt;
2289 int ch;
2290
2291 wt = IS_CHAR_CLASS (str);
2292 if (wt == 0)
2293 FREE_STACK_RETURN (REG_ECTYPE);
2294
2295 /* Throw away the ] at the end of the character
2296 class. */
2297 PATFETCH (c);
2298
2299 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2300
2301 for (ch = 0; ch < 1 << BYTEWIDTH; ++ch)
2302 {
2303 # ifdef _LIBC
2304 if (__iswctype (__btowc (ch), wt))
2305 SET_LIST_BIT (ch);
2306 # else
2307 if (iswctype (btowc (ch), wt))
2308 SET_LIST_BIT (ch);
2309 # endif
2310
2311 if (translate && (is_upper || is_lower)
2312 && (ISUPPER (ch) || ISLOWER (ch)))
2313 SET_LIST_BIT (ch);
2314 }
2315
2316 had_char_class = true;
2317 #else
2318 int ch;
2319 boolean is_alnum = STREQ (str, "alnum");
2320 boolean is_alpha = STREQ (str, "alpha");
2321 boolean is_blank = STREQ (str, "blank");
2322 boolean is_cntrl = STREQ (str, "cntrl");
2323 boolean is_digit = STREQ (str, "digit");
2324 boolean is_graph = STREQ (str, "graph");
2325 boolean is_lower = STREQ (str, "lower");
2326 boolean is_print = STREQ (str, "print");
2327 boolean is_punct = STREQ (str, "punct");
2328 boolean is_space = STREQ (str, "space");
2329 boolean is_upper = STREQ (str, "upper");
2330 boolean is_xdigit = STREQ (str, "xdigit");
2331
2332 if (!IS_CHAR_CLASS (str))
2333 FREE_STACK_RETURN (REG_ECTYPE);
2334
2335 /* Throw away the ] at the end of the character
2336 class. */
2337 PATFETCH (c);
2338
2339 if (p == pend) FREE_STACK_RETURN (REG_EBRACK);
2340
2341 for (ch = 0; ch < 1 << BYTEWIDTH; ch++)
2342 {
2343 /* This was split into 3 if's to
2344 avoid an arbitrary limit in some compiler. */
2345 if ( (is_alnum && ISALNUM (ch))
2346 || (is_alpha && ISALPHA (ch))
2347 || (is_blank && ISBLANK (ch))
2348 || (is_cntrl && ISCNTRL (ch)))
2349 SET_LIST_BIT (ch);
2350 if ( (is_digit && ISDIGIT (ch))
2351 || (is_graph && ISGRAPH (ch))
2352 || (is_lower && ISLOWER (ch))
2353 || (is_print && ISPRINT (ch)))
2354 SET_LIST_BIT (ch);
2355 if ( (is_punct && ISPUNCT (ch))
2356 || (is_space && ISSPACE (ch))
2357 || (is_upper && ISUPPER (ch))
2358 || (is_xdigit && ISXDIGIT (ch)))
2359 SET_LIST_BIT (ch);
2360 if ( translate && (is_upper || is_lower)
2361 && (ISUPPER (ch) || ISLOWER (ch)))
2362 SET_LIST_BIT (ch);
2363 }
2364 had_char_class = true;
2365 #endif /* libc || wctype.h */
2366 }
2367 else
2368 {
2369 c1++;
2370 while (c1--)
2371 PATUNFETCH;
2372 SET_LIST_BIT ('[');
2373 SET_LIST_BIT (':');
2374 had_char_class = false;
2375 }
2376 }
2377 else
2378 {
2379 had_char_class = false;
2380 SET_LIST_BIT (c);
2381 }
2382 }
2383
2384 /* Discard any (non)matching list bytes that are all 0 at the
2385 end of the map. Decrease the map-length byte too. */
2386 while ((int) b[-1] > 0 && b[b[-1] - 1] == 0)
2387 b[-1]--;
2388 b += b[-1];
2389 }
2390 break;
2391
2392
2393 case '(':
2394 if (syntax & RE_NO_BK_PARENS)
2395 goto handle_open;
2396 else
2397 goto normal_char;
2398
2399
2400 case ')':
2401 if (syntax & RE_NO_BK_PARENS)
2402 goto handle_close;
2403 else
2404 goto normal_char;
2405
2406
2407 case '\n':
2408 if (syntax & RE_NEWLINE_ALT)
2409 goto handle_alt;
2410 else
2411 goto normal_char;
2412
2413
2414 case '|':
2415 if (syntax & RE_NO_BK_VBAR)
2416 goto handle_alt;
2417 else
2418 goto normal_char;
2419
2420
2421 case '{':
2422 if (syntax & RE_INTERVALS && syntax & RE_NO_BK_BRACES)
2423 goto handle_interval;
2424 else
2425 goto normal_char;
2426
2427
2428 case '\\':
2429 if (p == pend) FREE_STACK_RETURN (REG_EESCAPE);
2430
2431 /* Do not translate the character after the \, so that we can
2432 distinguish, e.g., \B from \b, even if we normally would
2433 translate, e.g., B to b. */
2434 PATFETCH_RAW (c);
2435
2436 switch (c)
2437 {
2438 case '(':
2439 if (syntax & RE_NO_BK_PARENS)
2440 goto normal_backslash;
2441
2442 handle_open:
2443 bufp->re_nsub++;
2444 regnum++;
2445
2446 if (COMPILE_STACK_FULL)
2447 {
2448 RETALLOC (compile_stack.stack, compile_stack.size << 1,
2449 compile_stack_elt_t);
2450 if (compile_stack.stack == NULL) return REG_ESPACE;
2451
2452 compile_stack.size <<= 1;
2453 }
2454
2455 /* These are the values to restore when we hit end of this
2456 group. They are all relative offsets, so that if the
2457 whole pattern moves because of realloc, they will still
2458 be valid. */
2459 COMPILE_STACK_TOP.begalt_offset = begalt - bufp->buffer;
2460 COMPILE_STACK_TOP.fixup_alt_jump
2461 = fixup_alt_jump ? fixup_alt_jump - bufp->buffer + 1 : 0;
2462 COMPILE_STACK_TOP.laststart_offset = b - bufp->buffer;
2463 COMPILE_STACK_TOP.regnum = regnum;
2464
2465 /* We will eventually replace the 0 with the number of
2466 groups inner to this one. But do not push a
2467 start_memory for groups beyond the last one we can
2468 represent in the compiled pattern. */
2469 if (regnum <= MAX_REGNUM)
2470 {
2471 COMPILE_STACK_TOP.inner_group_offset = b - bufp->buffer + 2;
2472 BUF_PUSH_3 (start_memory, regnum, 0);
2473 }
2474
2475 compile_stack.avail++;
2476
2477 fixup_alt_jump = 0;
2478 laststart = 0;
2479 begalt = b;
2480 /* If we've reached MAX_REGNUM groups, then this open
2481 won't actually generate any code, so we'll have to
2482 clear pending_exact explicitly. */
2483 pending_exact = 0;
2484 break;
2485
2486
2487 case ')':
2488 if (syntax & RE_NO_BK_PARENS) goto normal_backslash;
2489
2490 if (COMPILE_STACK_EMPTY)
2491 {
2492 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
2493 goto normal_backslash;
2494 else
2495 FREE_STACK_RETURN (REG_ERPAREN);
2496 }
2497
2498 handle_close:
2499 if (fixup_alt_jump)
2500 { /* Push a dummy failure point at the end of the
2501 alternative for a possible future
2502 `pop_failure_jump' to pop. See comments at
2503 `push_dummy_failure' in `re_match_2'. */
2504 BUF_PUSH (push_dummy_failure);
2505
2506 /* We allocated space for this jump when we assigned
2507 to `fixup_alt_jump', in the `handle_alt' case below. */
2508 STORE_JUMP (jump_past_alt, fixup_alt_jump, b - 1);
2509 }
2510
2511 /* See similar code for backslashed left paren above. */
2512 if (COMPILE_STACK_EMPTY)
2513 {
2514 if (syntax & RE_UNMATCHED_RIGHT_PAREN_ORD)
2515 goto normal_char;
2516 else
2517 FREE_STACK_RETURN (REG_ERPAREN);
2518 }
2519
2520 /* Since we just checked for an empty stack above, this
2521 ``can't happen''. */
2522 assert (compile_stack.avail != 0);
2523 {
2524 /* We don't just want to restore into `regnum', because
2525 later groups should continue to be numbered higher,
2526 as in `(ab)c(de)' -- the second group is #2. */
2527 regnum_t this_group_regnum;
2528
2529 compile_stack.avail--;
2530 begalt = bufp->buffer + COMPILE_STACK_TOP.begalt_offset;
2531 fixup_alt_jump
2532 = COMPILE_STACK_TOP.fixup_alt_jump
2533 ? bufp->buffer + COMPILE_STACK_TOP.fixup_alt_jump - 1
2534 : 0;
2535 laststart = bufp->buffer + COMPILE_STACK_TOP.laststart_offset;
2536 this_group_regnum = COMPILE_STACK_TOP.regnum;
2537 /* If we've reached MAX_REGNUM groups, then this open
2538 won't actually generate any code, so we'll have to
2539 clear pending_exact explicitly. */
2540 pending_exact = 0;
2541
2542 /* We're at the end of the group, so now we know how many
2543 groups were inside this one. */
2544 if (this_group_regnum <= MAX_REGNUM)
2545 {
2546 unsigned char *inner_group_loc
2547 = bufp->buffer + COMPILE_STACK_TOP.inner_group_offset;
2548
2549 *inner_group_loc = regnum - this_group_regnum;
2550 BUF_PUSH_3 (stop_memory, this_group_regnum,
2551 regnum - this_group_regnum);
2552 }
2553 }
2554 break;
2555
2556
2557 case '|': /* `\|'. */
2558 if (syntax & RE_LIMITED_OPS || syntax & RE_NO_BK_VBAR)
2559 goto normal_backslash;
2560 handle_alt:
2561 if (syntax & RE_LIMITED_OPS)
2562 goto normal_char;
2563
2564 /* Insert before the previous alternative a jump which
2565 jumps to this alternative if the former fails. */
2566 GET_BUFFER_SPACE (3);
2567 INSERT_JUMP (on_failure_jump, begalt, b + 6);
2568 pending_exact = 0;
2569 b += 3;
2570
2571 /* The alternative before this one has a jump after it
2572 which gets executed if it gets matched. Adjust that
2573 jump so it will jump to this alternative's analogous
2574 jump (put in below, which in turn will jump to the next
2575 (if any) alternative's such jump, etc.). The last such
2576 jump jumps to the correct final destination. A picture:
2577 _____ _____
2578 | | | |
2579 | v | v
2580 a | b | c
2581
2582 If we are at `b', then fixup_alt_jump right now points to a
2583 three-byte space after `a'. We'll put in the jump, set
2584 fixup_alt_jump to right after `b', and leave behind three
2585 bytes which we'll fill in when we get to after `c'. */
2586
2587 if (fixup_alt_jump)
2588 STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
2589
2590 /* Mark and leave space for a jump after this alternative,
2591 to be filled in later either by next alternative or
2592 when know we're at the end of a series of alternatives. */
2593 fixup_alt_jump = b;
2594 GET_BUFFER_SPACE (3);
2595 b += 3;
2596
2597 laststart = 0;
2598 begalt = b;
2599 break;
2600
2601
2602 case '{':
2603 /* If \{ is a literal. */
2604 if (!(syntax & RE_INTERVALS)
2605 /* If we're at `\{' and it's not the open-interval
2606 operator. */
2607 || ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
2608 || (p - 2 == pattern && p == pend))
2609 goto normal_backslash;
2610
2611 handle_interval:
2612 {
2613 /* If got here, then the syntax allows intervals. */
2614
2615 /* At least (most) this many matches must be made. */
2616 int lower_bound = -1, upper_bound = -1;
2617
2618 beg_interval = p - 1;
2619
2620 if (p == pend)
2621 {
2622 if (!(syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
2623 goto unfetch_interval;
2624 else
2625 FREE_STACK_RETURN (REG_EBRACE);
2626 }
2627
2628 GET_UNSIGNED_NUMBER (lower_bound);
2629
2630 if (c == ',')
2631 {
2632 GET_UNSIGNED_NUMBER (upper_bound);
2633 if ((!(syntax & RE_NO_BK_BRACES) && c != '\\')
2634 || ((syntax & RE_NO_BK_BRACES) && c != '}'))
2635 FREE_STACK_RETURN (REG_BADBR);
2636
2637 if (upper_bound < 0)
2638 upper_bound = RE_DUP_MAX;
2639 }
2640 else
2641 /* Interval such as `{1}' => match exactly once. */
2642 upper_bound = lower_bound;
2643
2644 if (lower_bound < 0 || upper_bound > RE_DUP_MAX
2645 || lower_bound > upper_bound)
2646 {
2647 if (!(syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
2648 goto unfetch_interval;
2649 else
2650 FREE_STACK_RETURN (REG_BADBR);
2651 }
2652
2653 if (!(syntax & RE_NO_BK_BRACES))
2654 {
2655 if (c != '\\') FREE_STACK_RETURN (REG_EBRACE);
2656
2657 PATFETCH (c);
2658 }
2659
2660 if (c != '}')
2661 {
2662 if (!(syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
2663 goto unfetch_interval;
2664 else
2665 FREE_STACK_RETURN (REG_BADBR);
2666 }
2667
2668 /* We just parsed a valid interval. */
2669
2670 /* If it's invalid to have no preceding re. */
2671 if (!laststart)
2672 {
2673 if (syntax & RE_CONTEXT_INVALID_OPS)
2674 FREE_STACK_RETURN (REG_BADRPT);
2675 else if (syntax & RE_CONTEXT_INDEP_OPS)
2676 laststart = b;
2677 else
2678 goto unfetch_interval;
2679 }
2680
2681 /* If the upper bound is zero, don't want to succeed at
2682 all; jump from `laststart' to `b + 3', which will be
2683 the end of the buffer after we insert the jump. */
2684 if (upper_bound == 0)
2685 {
2686 GET_BUFFER_SPACE (3);
2687 INSERT_JUMP (jump, laststart, b + 3);
2688 b += 3;
2689 }
2690
2691 /* Otherwise, we have a nontrivial interval. When
2692 we're all done, the pattern will look like:
2693 set_number_at <jump count> <upper bound>
2694 set_number_at <succeed_n count> <lower bound>
2695 succeed_n <after jump addr> <succeed_n count>
2696 <body of loop>
2697 jump_n <succeed_n addr> <jump count>
2698 (The upper bound and `jump_n' are omitted if
2699 `upper_bound' is 1, though.) */
2700 else
2701 { /* If the upper bound is > 1, we need to insert
2702 more at the end of the loop. */
2703 unsigned nbytes = 10 + (upper_bound > 1) * 10;
2704
2705 GET_BUFFER_SPACE (nbytes);
2706
2707 /* Initialize lower bound of the `succeed_n', even
2708 though it will be set during matching by its
2709 attendant `set_number_at' (inserted next),
2710 because `re_compile_fastmap' needs to know.
2711 Jump to the `jump_n' we might insert below. */
2712 INSERT_JUMP2 (succeed_n, laststart,
2713 b + 5 + (upper_bound > 1) * 5,
2714 lower_bound);
2715 b += 5;
2716
2717 /* Code to initialize the lower bound. Insert
2718 before the `succeed_n'. The `5' is the last two
2719 bytes of this `set_number_at', plus 3 bytes of
2720 the following `succeed_n'. */
2721 insert_op2 (set_number_at, laststart, 5, lower_bound, b);
2722 b += 5;
2723
2724 if (upper_bound > 1)
2725 { /* More than one repetition is allowed, so
2726 append a backward jump to the `succeed_n'
2727 that starts this interval.
2728
2729 When we've reached this during matching,
2730 we'll have matched the interval once, so
2731 jump back only `upper_bound - 1' times. */
2732 STORE_JUMP2 (jump_n, b, laststart + 5,
2733 upper_bound - 1);
2734 b += 5;
2735
2736 /* The location we want to set is the second
2737 parameter of the `jump_n'; that is `b-2' as
2738 an absolute address. `laststart' will be
2739 the `set_number_at' we're about to insert;
2740 `laststart+3' the number to set, the source
2741 for the relative address. But we are
2742 inserting into the middle of the pattern --
2743 so everything is getting moved up by 5.
2744 Conclusion: (b - 2) - (laststart + 3) + 5,
2745 i.e., b - laststart.
2746
2747 We insert this at the beginning of the loop
2748 so that if we fail during matching, we'll
2749 reinitialize the bounds. */
2750 insert_op2 (set_number_at, laststart, b - laststart,
2751 upper_bound - 1, b);
2752 b += 5;
2753 }
2754 }
2755 pending_exact = 0;
2756 beg_interval = NULL;
2757 }
2758 break;
2759
2760 unfetch_interval:
2761 /* If an invalid interval, match the characters as literals. */
2762 assert (beg_interval);
2763 p = beg_interval;
2764 beg_interval = NULL;
2765
2766 /* normal_char and normal_backslash need `c'. */
2767 PATFETCH (c);
2768
2769 if (!(syntax & RE_NO_BK_BRACES))
2770 {
2771 if (p > pattern && p[-1] == '\\')
2772 goto normal_backslash;
2773 }
2774 goto normal_char;
2775
2776 #ifdef emacs
2777 /* There is no way to specify the before_dot and after_dot
2778 operators. rms says this is ok. --karl */
2779 case '=':
2780 BUF_PUSH (at_dot);
2781 break;
2782
2783 case 's':
2784 laststart = b;
2785 PATFETCH (c);
2786 BUF_PUSH_2 (syntaxspec, syntax_spec_code[c]);
2787 break;
2788
2789 case 'S':
2790 laststart = b;
2791 PATFETCH (c);
2792 BUF_PUSH_2 (notsyntaxspec, syntax_spec_code[c]);
2793 break;
2794 #endif /* emacs */
2795
2796
2797 case 'w':
2798 if (syntax & RE_NO_GNU_OPS)
2799 goto normal_char;
2800 laststart = b;
2801 BUF_PUSH (wordchar);
2802 break;
2803
2804
2805 case 'W':
2806 if (syntax & RE_NO_GNU_OPS)
2807 goto normal_char;
2808 laststart = b;
2809 BUF_PUSH (notwordchar);
2810 break;
2811
2812
2813 case '<':
2814 if (syntax & RE_NO_GNU_OPS)
2815 goto normal_char;
2816 BUF_PUSH (wordbeg);
2817 break;
2818
2819 case '>':
2820 if (syntax & RE_NO_GNU_OPS)
2821 goto normal_char;
2822 BUF_PUSH (wordend);
2823 break;
2824
2825 case 'b':
2826 if (syntax & RE_NO_GNU_OPS)
2827 goto normal_char;
2828 BUF_PUSH (wordbound);
2829 break;
2830
2831 case 'B':
2832 if (syntax & RE_NO_GNU_OPS)
2833 goto normal_char;
2834 BUF_PUSH (notwordbound);
2835 break;
2836
2837 case '`':
2838 if (syntax & RE_NO_GNU_OPS)
2839 goto normal_char;
2840 BUF_PUSH (begbuf);
2841 break;
2842
2843 case '\'':
2844 if (syntax & RE_NO_GNU_OPS)
2845 goto normal_char;
2846 BUF_PUSH (endbuf);
2847 break;
2848
2849 case '1': case '2': case '3': case '4': case '5':
2850 case '6': case '7': case '8': case '9':
2851 if (syntax & RE_NO_BK_REFS)
2852 goto normal_char;
2853
2854 c1 = c - '0';
2855
2856 if (c1 > regnum)
2857 FREE_STACK_RETURN (REG_ESUBREG);
2858
2859 /* Can't back reference to a subexpression if inside of it. */
2860 if (group_in_compile_stack (compile_stack, (regnum_t) c1))
2861 goto normal_char;
2862
2863 laststart = b;
2864 BUF_PUSH_2 (duplicate, c1);
2865 break;
2866
2867
2868 case '+':
2869 case '?':
2870 if (syntax & RE_BK_PLUS_QM)
2871 goto handle_plus;
2872 else
2873 goto normal_backslash;
2874
2875 default:
2876 normal_backslash:
2877 /* You might think it would be useful for \ to mean
2878 not to translate; but if we don't translate it
2879 it will never match anything. */
2880 c = TRANSLATE (c);
2881 goto normal_char;
2882 }
2883 break;
2884
2885
2886 default:
2887 /* Expects the character in `c'. */
2888 normal_char:
2889 /* If no exactn currently being built. */
2890 if (!pending_exact
2891
2892 /* If last exactn not at current position. */
2893 || pending_exact + *pending_exact + 1 != b
2894
2895 /* We have only one byte following the exactn for the count. */
2896 || *pending_exact == (1 << BYTEWIDTH) - 1
2897
2898 /* If followed by a repetition operator. */
2899 || *p == '*' || *p == '^'
2900 || ((syntax & RE_BK_PLUS_QM)
2901 ? *p == '\\' && (p[1] == '+' || p[1] == '?')
2902 : (*p == '+' || *p == '?'))
2903 || ((syntax & RE_INTERVALS)
2904 && ((syntax & RE_NO_BK_BRACES)
2905 ? *p == '{'
2906 : (p[0] == '\\' && p[1] == '{'))))
2907 {
2908 /* Start building a new exactn. */
2909
2910 laststart = b;
2911
2912 BUF_PUSH_2 (exactn, 0);
2913 pending_exact = b - 1;
2914 }
2915
2916 BUF_PUSH (c);
2917 (*pending_exact)++;
2918 break;
2919 } /* switch (c) */
2920 } /* while p != pend */
2921
2922
2923 /* Through the pattern now. */
2924
2925 if (fixup_alt_jump)
2926 STORE_JUMP (jump_past_alt, fixup_alt_jump, b);
2927
2928 if (!COMPILE_STACK_EMPTY)
2929 FREE_STACK_RETURN (REG_EPAREN);
2930
2931 /* If we don't want backtracking, force success
2932 the first time we reach the end of the compiled pattern. */
2933 if (syntax & RE_NO_POSIX_BACKTRACKING)
2934 BUF_PUSH (succeed);
2935
2936 free (compile_stack.stack);
2937
2938 /* We have succeeded; set the length of the buffer. */
2939 bufp->used = b - bufp->buffer;
2940
2941 #ifdef DEBUG
2942 if (debug)
2943 {
2944 DEBUG_PRINT1 ("\nCompiled pattern: \n");
2945 print_compiled_pattern (bufp);
2946 }
2947 #endif /* DEBUG */
2948
2949 #ifndef MATCH_MAY_ALLOCATE
2950 /* Initialize the failure stack to the largest possible stack. This
2951 isn't necessary unless we're trying to avoid calling alloca in
2952 the search and match routines. */
2953 {
2954 int num_regs = bufp->re_nsub + 1;
2955
2956 /* Since DOUBLE_FAIL_STACK refuses to double only if the current size
2957 is strictly greater than re_max_failures, the largest possible stack
2958 is 2 * re_max_failures failure points. */
2959 if (fail_stack.size < (2 * re_max_failures * MAX_FAILURE_ITEMS))
2960 {
2961 fail_stack.size = (2 * re_max_failures * MAX_FAILURE_ITEMS);
2962
2963 # ifdef emacs
2964 if (! fail_stack.stack)
2965 fail_stack.stack
2966 = (fail_stack_elt_t *) xmalloc (fail_stack.size
2967 * sizeof (fail_stack_elt_t));
2968 else
2969 fail_stack.stack
2970 = (fail_stack_elt_t *) xrealloc (fail_stack.stack,
2971 (fail_stack.size
2972 * sizeof (fail_stack_elt_t)));
2973 # else /* not emacs */
2974 if (! fail_stack.stack)
2975 fail_stack.stack
2976 = (fail_stack_elt_t *) malloc (fail_stack.size
2977 * sizeof (fail_stack_elt_t));
2978 else
2979 fail_stack.stack
2980 = (fail_stack_elt_t *) realloc (fail_stack.stack,
2981 (fail_stack.size
2982 * sizeof (fail_stack_elt_t)));
2983 # endif /* not emacs */
2984 }
2985
2986 regex_grow_registers (num_regs);
2987 }
2988 #endif /* not MATCH_MAY_ALLOCATE */
2989
2990 return REG_NOERROR;
2991 } /* regex_compile */
2992
2993 /* Subroutines for `regex_compile'. */
2994
2995 /* Store OP at LOC followed by two-byte integer parameter ARG. */
2996
2997 static void
2998 store_op1 (op, loc, arg)
2999 re_opcode_t op;
3000 unsigned char *loc;
3001 int arg;
3002 {
3003 *loc = (unsigned char) op;
3004 STORE_NUMBER (loc + 1, arg);
3005 }
3006
3007
3008 /* Like `store_op1', but for two two-byte parameters ARG1 and ARG2. */
3009
3010 static void
3011 store_op2 (op, loc, arg1, arg2)
3012 re_opcode_t op;
3013 unsigned char *loc;
3014 int arg1, arg2;
3015 {
3016 *loc = (unsigned char) op;
3017 STORE_NUMBER (loc + 1, arg1);
3018 STORE_NUMBER (loc + 3, arg2);
3019 }
3020
3021
3022 /* Copy the bytes from LOC to END to open up three bytes of space at LOC
3023 for OP followed by two-byte integer parameter ARG. */
3024
3025 static void
3026 insert_op1 (op, loc, arg, end)
3027 re_opcode_t op;
3028 unsigned char *loc;
3029 int arg;
3030 unsigned char *end;
3031 {
3032 register unsigned char *pfrom = end;
3033 register unsigned char *pto = end + 3;
3034
3035 while (pfrom != loc)
3036 *--pto = *--pfrom;
3037
3038 store_op1 (op, loc, arg);
3039 }
3040
3041
3042 /* Like `insert_op1', but for two two-byte parameters ARG1 and ARG2. */
3043
3044 static void
3045 insert_op2 (op, loc, arg1, arg2, end)
3046 re_opcode_t op;
3047 unsigned char *loc;
3048 int arg1, arg2;
3049 unsigned char *end;
3050 {
3051 register unsigned char *pfrom = end;
3052 register unsigned char *pto = end + 5;
3053
3054 while (pfrom != loc)
3055 *--pto = *--pfrom;
3056
3057 store_op2 (op, loc, arg1, arg2);
3058 }
3059
3060
3061 /* P points to just after a ^ in PATTERN. Return true if that ^ comes
3062 after an alternative or a begin-subexpression. We assume there is at
3063 least one character before the ^. */
3064
3065 static boolean
3066 at_begline_loc_p (pattern, p, syntax)
3067 const char *pattern, *p;
3068 reg_syntax_t syntax;
3069 {
3070 const char *prev = p - 2;
3071 boolean prev_prev_backslash = prev > pattern && prev[-1] == '\\';
3072
3073 return
3074 /* After a subexpression? */
3075 (*prev == '(' && (syntax & RE_NO_BK_PARENS || prev_prev_backslash))
3076 /* After an alternative? */
3077 || (*prev == '|' && (syntax & RE_NO_BK_VBAR || prev_prev_backslash));
3078 }
3079
3080
3081 /* The dual of at_begline_loc_p. This one is for $. We assume there is
3082 at least one character after the $, i.e., `P < PEND'. */
3083
3084 static boolean
3085 at_endline_loc_p (p, pend, syntax)
3086 const char *p, *pend;
3087 reg_syntax_t syntax;
3088 {
3089 const char *next = p;
3090 boolean next_backslash = *next == '\\';
3091 const char *next_next = p + 1 < pend ? p + 1 : 0;
3092
3093 return
3094 /* Before a subexpression? */
3095 (syntax & RE_NO_BK_PARENS ? *next == ')'
3096 : next_backslash && next_next && *next_next == ')')
3097 /* Before an alternative? */
3098 || (syntax & RE_NO_BK_VBAR ? *next == '|'
3099 : next_backslash && next_next && *next_next == '|');
3100 }
3101
3102
3103 /* Returns true if REGNUM is in one of COMPILE_STACK's elements and
3104 false if it's not. */
3105
3106 static boolean
3107 group_in_compile_stack (compile_stack, regnum)
3108 compile_stack_type compile_stack;
3109 regnum_t regnum;
3110 {
3111 int this_element;
3112
3113 for (this_element = compile_stack.avail - 1;
3114 this_element >= 0;
3115 this_element--)
3116 if (compile_stack.stack[this_element].regnum == regnum)
3117 return true;
3118
3119 return false;
3120 }
3121
3122
3123 /* Read the ending character of a range (in a bracket expression) from the
3124 uncompiled pattern *P_PTR (which ends at PEND). We assume the
3125 starting character is in `P[-2]'. (`P[-1]' is the character `-'.)
3126 Then we set the translation of all bits between the starting and
3127 ending characters (inclusive) in the compiled pattern B.
3128
3129 Return an error code.
3130
3131 We use these short variable names so we can use the same macros as
3132 `regex_compile' itself. */
3133
3134 static reg_errcode_t
3135 compile_range (p_ptr, pend, translate, syntax, b)
3136 const char **p_ptr, *pend;
3137 RE_TRANSLATE_TYPE translate;
3138 reg_syntax_t syntax;
3139 unsigned char *b;
3140 {
3141 unsigned this_char;
3142
3143 const char *p = *p_ptr;
3144 reg_errcode_t ret;
3145 char range_start[2];
3146 char range_end[2];
3147 char ch[2];
3148
3149 if (p == pend)
3150 return REG_ERANGE;
3151
3152 /* Fetch the endpoints without translating them; the
3153 appropriate translation is done in the bit-setting loop below. */
3154 range_start[0] = p[-2];
3155 range_start[1] = '\0';
3156 range_end[0] = p[0];
3157 range_end[1] = '\0';
3158
3159 /* Have to increment the pointer into the pattern string, so the
3160 caller isn't still at the ending character. */
3161 (*p_ptr)++;
3162
3163 /* Report an error if the range is empty and the syntax prohibits this. */
3164 ret = syntax & RE_NO_EMPTY_RANGES ? REG_ERANGE : REG_NOERROR;
3165
3166 /* Here we see why `this_char' has to be larger than an `unsigned
3167 char' -- we would otherwise go into an infinite loop, since all
3168 characters <= 0xff. */
3169 ch[1] = '\0';
3170 for (this_char = 0; this_char <= (unsigned char) -1; ++this_char)
3171 {
3172 ch[0] = this_char;
3173 if (strcoll (range_start, ch) <= 0 && strcoll (ch, range_end) <= 0)
3174 {
3175 SET_LIST_BIT (TRANSLATE (this_char));
3176 ret = REG_NOERROR;
3177 }
3178 }
3179
3180 return ret;
3181 }
3182
3183 /* re_compile_fastmap computes a ``fastmap'' for the compiled pattern in
3184 BUFP. A fastmap records which of the (1 << BYTEWIDTH) possible
3185 characters can start a string that matches the pattern. This fastmap
3186 is used by re_search to skip quickly over impossible starting points.
3187
3188 The caller must supply the address of a (1 << BYTEWIDTH)-byte data
3189 area as BUFP->fastmap.
3190
3191 We set the `fastmap', `fastmap_accurate', and `can_be_null' fields in
3192 the pattern buffer.
3193
3194 Returns 0 if we succeed, -2 if an internal error. */
3195
3196 int
3197 re_compile_fastmap (bufp)
3198 struct re_pattern_buffer *bufp;
3199 {
3200 int j, k;
3201 #ifdef MATCH_MAY_ALLOCATE
3202 fail_stack_type fail_stack;
3203 #endif
3204 #ifndef REGEX_MALLOC
3205 char *destination;
3206 #endif
3207
3208 register char *fastmap = bufp->fastmap;
3209 unsigned char *pattern = bufp->buffer;
3210 unsigned char *p = pattern;
3211 register unsigned char *pend = pattern + bufp->used;
3212
3213 #ifdef REL_ALLOC
3214 /* This holds the pointer to the failure stack, when
3215 it is allocated relocatably. */
3216 fail_stack_elt_t *failure_stack_ptr;
3217 #endif
3218
3219 /* Assume that each path through the pattern can be null until
3220 proven otherwise. We set this false at the bottom of switch
3221 statement, to which we get only if a particular path doesn't
3222 match the empty string. */
3223 boolean path_can_be_null = true;
3224
3225 /* We aren't doing a `succeed_n' to begin with. */
3226 boolean succeed_n_p = false;
3227
3228 assert (fastmap != NULL && p != NULL);
3229
3230 INIT_FAIL_STACK ();
3231 bzero (fastmap, 1 << BYTEWIDTH); /* Assume nothing's valid. */
3232 bufp->fastmap_accurate = 1; /* It will be when we're done. */
3233 bufp->can_be_null = 0;
3234
3235 while (1)
3236 {
3237 if (p == pend || *p == succeed)
3238 {
3239 /* We have reached the (effective) end of pattern. */
3240 if (!FAIL_STACK_EMPTY ())
3241 {
3242 bufp->can_be_null |= path_can_be_null;
3243
3244 /* Reset for next path. */
3245 path_can_be_null = true;
3246
3247 p = fail_stack.stack[--fail_stack.avail].pointer;
3248
3249 continue;
3250 }
3251 else
3252 break;
3253 }
3254
3255 /* We should never be about to go beyond the end of the pattern. */
3256 assert (p < pend);
3257
3258 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
3259 {
3260
3261 /* I guess the idea here is to simply not bother with a fastmap
3262 if a backreference is used, since it's too hard to figure out
3263 the fastmap for the corresponding group. Setting
3264 `can_be_null' stops `re_search_2' from using the fastmap, so
3265 that is all we do. */
3266 case duplicate:
3267 bufp->can_be_null = 1;
3268 goto done;
3269
3270
3271 /* Following are the cases which match a character. These end
3272 with `break'. */
3273
3274 case exactn:
3275 fastmap[p[1]] = 1;
3276 break;
3277
3278
3279 case charset:
3280 for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
3281 if (p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH)))
3282 fastmap[j] = 1;
3283 break;
3284
3285
3286 case charset_not:
3287 /* Chars beyond end of map must be allowed. */
3288 for (j = *p * BYTEWIDTH; j < (1 << BYTEWIDTH); j++)
3289 fastmap[j] = 1;
3290
3291 for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--)
3292 if (!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))))
3293 fastmap[j] = 1;
3294 break;
3295
3296
3297 case wordchar:
3298 for (j = 0; j < (1 << BYTEWIDTH); j++)
3299 if (SYNTAX (j) == Sword)
3300 fastmap[j] = 1;
3301 break;
3302
3303
3304 case notwordchar:
3305 for (j = 0; j < (1 << BYTEWIDTH); j++)
3306 if (SYNTAX (j) != Sword)
3307 fastmap[j] = 1;
3308 break;
3309
3310
3311 case anychar:
3312 {
3313 int fastmap_newline = fastmap['\n'];
3314
3315 /* `.' matches anything ... */
3316 for (j = 0; j < (1 << BYTEWIDTH); j++)
3317 fastmap[j] = 1;
3318
3319 /* ... except perhaps newline. */
3320 if (!(bufp->syntax & RE_DOT_NEWLINE))
3321 fastmap['\n'] = fastmap_newline;
3322
3323 /* Return if we have already set `can_be_null'; if we have,
3324 then the fastmap is irrelevant. Something's wrong here. */
3325 else if (bufp->can_be_null)
3326 goto done;
3327
3328 /* Otherwise, have to check alternative paths. */
3329 break;
3330 }
3331
3332 #ifdef emacs
3333 case syntaxspec:
3334 k = *p++;
3335 for (j = 0; j < (1 << BYTEWIDTH); j++)
3336 if (SYNTAX (j) == (enum syntaxcode) k)
3337 fastmap[j] = 1;
3338 break;
3339
3340
3341 case notsyntaxspec:
3342 k = *p++;
3343 for (j = 0; j < (1 << BYTEWIDTH); j++)
3344 if (SYNTAX (j) != (enum syntaxcode) k)
3345 fastmap[j] = 1;
3346 break;
3347
3348
3349 /* All cases after this match the empty string. These end with
3350 `continue'. */
3351
3352
3353 case before_dot:
3354 case at_dot:
3355 case after_dot:
3356 continue;
3357 #endif /* emacs */
3358
3359
3360 case no_op:
3361 case begline:
3362 case endline:
3363 case begbuf:
3364 case endbuf:
3365 case wordbound:
3366 case notwordbound:
3367 case wordbeg:
3368 case wordend:
3369 case push_dummy_failure:
3370 continue;
3371
3372
3373 case jump_n:
3374 case pop_failure_jump:
3375 case maybe_pop_jump:
3376 case jump:
3377 case jump_past_alt:
3378 case dummy_failure_jump:
3379 EXTRACT_NUMBER_AND_INCR (j, p);
3380 p += j;
3381 if (j > 0)
3382 continue;
3383
3384 /* Jump backward implies we just went through the body of a
3385 loop and matched nothing. Opcode jumped to should be
3386 `on_failure_jump' or `succeed_n'. Just treat it like an
3387 ordinary jump. For a * loop, it has pushed its failure
3388 point already; if so, discard that as redundant. */
3389 if ((re_opcode_t) *p != on_failure_jump
3390 && (re_opcode_t) *p != succeed_n)
3391 continue;
3392
3393 p++;
3394 EXTRACT_NUMBER_AND_INCR (j, p);
3395 p += j;
3396
3397 /* If what's on the stack is where we are now, pop it. */
3398 if (!FAIL_STACK_EMPTY ()
3399 && fail_stack.stack[fail_stack.avail - 1].pointer == p)
3400 fail_stack.avail--;
3401
3402 continue;
3403
3404
3405 case on_failure_jump:
3406 case on_failure_keep_string_jump:
3407 handle_on_failure_jump:
3408 EXTRACT_NUMBER_AND_INCR (j, p);
3409
3410 /* For some patterns, e.g., `(a?)?', `p+j' here points to the
3411 end of the pattern. We don't want to push such a point,
3412 since when we restore it above, entering the switch will
3413 increment `p' past the end of the pattern. We don't need
3414 to push such a point since we obviously won't find any more
3415 fastmap entries beyond `pend'. Such a pattern can match
3416 the null string, though. */
3417 if (p + j < pend)
3418 {
3419 if (!PUSH_PATTERN_OP (p + j, fail_stack))
3420 {
3421 RESET_FAIL_STACK ();
3422 return -2;
3423 }
3424 }
3425 else
3426 bufp->can_be_null = 1;
3427
3428 if (succeed_n_p)
3429 {
3430 EXTRACT_NUMBER_AND_INCR (k, p); /* Skip the n. */
3431 succeed_n_p = false;
3432 }
3433
3434 continue;
3435
3436
3437 case succeed_n:
3438 /* Get to the number of times to succeed. */
3439 p += 2;
3440
3441 /* Increment p past the n for when k != 0. */
3442 EXTRACT_NUMBER_AND_INCR (k, p);
3443 if (k == 0)
3444 {
3445 p -= 4;
3446 succeed_n_p = true; /* Spaghetti code alert. */
3447 goto handle_on_failure_jump;
3448 }
3449 continue;
3450
3451
3452 case set_number_at:
3453 p += 4;
3454 continue;
3455
3456
3457 case start_memory:
3458 case stop_memory:
3459 p += 2;
3460 continue;
3461
3462
3463 default:
3464 abort (); /* We have listed all the cases. */
3465 } /* switch *p++ */
3466
3467 /* Getting here means we have found the possible starting
3468 characters for one path of the pattern -- and that the empty
3469 string does not match. We need not follow this path further.
3470 Instead, look at the next alternative (remembered on the
3471 stack), or quit if no more. The test at the top of the loop
3472 does these things. */
3473 path_can_be_null = false;
3474 p = pend;
3475 } /* while p */
3476
3477 /* Set `can_be_null' for the last path (also the first path, if the
3478 pattern is empty). */
3479 bufp->can_be_null |= path_can_be_null;
3480
3481 done:
3482 RESET_FAIL_STACK ();
3483 return 0;
3484 } /* re_compile_fastmap */
3485 #ifdef _LIBC
3486 weak_alias (__re_compile_fastmap, re_compile_fastmap)
3487 #endif
3488
3489 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
3490 ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
3491 this memory for recording register information. STARTS and ENDS
3492 must be allocated using the malloc library routine, and must each
3493 be at least NUM_REGS * sizeof (regoff_t) bytes long.
3494
3495 If NUM_REGS == 0, then subsequent matches should allocate their own
3496 register data.
3497
3498 Unless this function is called, the first search or match using
3499 PATTERN_BUFFER will allocate its own register data, without
3500 freeing the old data. */
3501
3502 void
3503 re_set_registers (bufp, regs, num_regs, starts, ends)
3504 struct re_pattern_buffer *bufp;
3505 struct re_registers *regs;
3506 unsigned num_regs;
3507 regoff_t *starts, *ends;
3508 {
3509 if (num_regs)
3510 {
3511 bufp->regs_allocated = REGS_REALLOCATE;
3512 regs->num_regs = num_regs;
3513 regs->start = starts;
3514 regs->end = ends;
3515 }
3516 else
3517 {
3518 bufp->regs_allocated = REGS_UNALLOCATED;
3519 regs->num_regs = 0;
3520 regs->start = regs->end = (regoff_t *) 0;
3521 }
3522 }
3523 #ifdef _LIBC
3524 weak_alias (__re_set_registers, re_set_registers)
3525 #endif
3526
3527 /* Searching routines. */
3528
3529 /* Like re_search_2, below, but only one string is specified, and
3530 doesn't let you say where to stop matching. */
3531
3532 int
3533 re_search (bufp, string, size, startpos, range, regs)
3534 struct re_pattern_buffer *bufp;
3535 const char *string;
3536 int size, startpos, range;
3537 struct re_registers *regs;
3538 {
3539 return re_search_2 (bufp, NULL, 0, string, size, startpos, range,
3540 regs, size);
3541 }
3542 #ifdef _LIBC
3543 weak_alias (__re_search, re_search)
3544 #endif
3545
3546
3547 /* Using the compiled pattern in BUFP->buffer, first tries to match the
3548 virtual concatenation of STRING1 and STRING2, starting first at index
3549 STARTPOS, then at STARTPOS + 1, and so on.
3550
3551 STRING1 and STRING2 have length SIZE1 and SIZE2, respectively.
3552
3553 RANGE is how far to scan while trying to match. RANGE = 0 means try
3554 only at STARTPOS; in general, the last start tried is STARTPOS +
3555 RANGE.
3556
3557 In REGS, return the indices of the virtual concatenation of STRING1
3558 and STRING2 that matched the entire BUFP->buffer and its contained
3559 subexpressions.
3560
3561 Do not consider matching one past the index STOP in the virtual
3562 concatenation of STRING1 and STRING2.
3563
3564 We return either the position in the strings at which the match was
3565 found, -1 if no match, or -2 if error (such as failure
3566 stack overflow). */
3567
3568 int
3569 re_search_2 (bufp, string1, size1, string2, size2, startpos, range, regs, stop)
3570 struct re_pattern_buffer *bufp;
3571 const char *string1, *string2;
3572 int size1, size2;
3573 int startpos;
3574 int range;
3575 struct re_registers *regs;
3576 int stop;
3577 {
3578 int val;
3579 register char *fastmap = bufp->fastmap;
3580 register RE_TRANSLATE_TYPE translate = bufp->translate;
3581 int total_size = size1 + size2;
3582 int endpos = startpos + range;
3583
3584 /* Check for out-of-range STARTPOS. */
3585 if (startpos < 0 || startpos > total_size)
3586 return -1;
3587
3588 /* Fix up RANGE if it might eventually take us outside
3589 the virtual concatenation of STRING1 and STRING2.
3590 Make sure we won't move STARTPOS below 0 or above TOTAL_SIZE. */
3591 if (endpos < 0)
3592 range = 0 - startpos;
3593 else if (endpos > total_size)
3594 range = total_size - startpos;
3595
3596 /* If the search isn't to be a backwards one, don't waste time in a
3597 search for a pattern that must be anchored. */
3598 if (bufp->used > 0 && range > 0
3599 && ((re_opcode_t) bufp->buffer[0] == begbuf
3600 /* `begline' is like `begbuf' if it cannot match at newlines. */
3601 || ((re_opcode_t) bufp->buffer[0] == begline
3602 && !bufp->newline_anchor)))
3603 {
3604 if (startpos > 0)
3605 return -1;
3606 else
3607 range = 1;
3608 }
3609
3610 #ifdef emacs
3611 /* In a forward search for something that starts with \=.
3612 don't keep searching past point. */
3613 if (bufp->used > 0 && (re_opcode_t) bufp->buffer[0] == at_dot && range > 0)
3614 {
3615 range = PT - startpos;
3616 if (range <= 0)
3617 return -1;
3618 }
3619 #endif /* emacs */
3620
3621 /* Update the fastmap now if not correct already. */
3622 if (fastmap && !bufp->fastmap_accurate)
3623 if (re_compile_fastmap (bufp) == -2)
3624 return -2;
3625
3626 /* Loop through the string, looking for a place to start matching. */
3627 for (;;)
3628 {
3629 /* If a fastmap is supplied, skip quickly over characters that
3630 cannot be the start of a match. If the pattern can match the
3631 null string, however, we don't need to skip characters; we want
3632 the first null string. */
3633 if (fastmap && startpos < total_size && !bufp->can_be_null)
3634 {
3635 if (range > 0) /* Searching forwards. */
3636 {
3637 register const char *d;
3638 register int lim = 0;
3639 int irange = range;
3640
3641 if (startpos < size1 && startpos + range >= size1)
3642 lim = range - (size1 - startpos);
3643
3644 d = (startpos >= size1 ? string2 - size1 : string1) + startpos;
3645
3646 /* Written out as an if-else to avoid testing `translate'
3647 inside the loop. */
3648 if (translate)
3649 while (range > lim
3650 && !fastmap[(unsigned char)
3651 translate[(unsigned char) *d++]])
3652 range--;
3653 else
3654 while (range > lim && !fastmap[(unsigned char) *d++])
3655 range--;
3656
3657 startpos += irange - range;
3658 }
3659 else /* Searching backwards. */
3660 {
3661 register char c = (size1 == 0 || startpos >= size1
3662 ? string2[startpos - size1]
3663 : string1[startpos]);
3664
3665 if (!fastmap[(unsigned char) TRANSLATE (c)])
3666 goto advance;
3667 }
3668 }
3669
3670 /* If can't match the null string, and that's all we have left, fail. */
3671 if (range >= 0 && startpos == total_size && fastmap
3672 && !bufp->can_be_null)
3673 return -1;
3674
3675 val = re_match_2_internal (bufp, string1, size1, string2, size2,
3676 startpos, regs, stop);
3677 #ifndef REGEX_MALLOC
3678 # ifdef C_ALLOCA
3679 alloca (0);
3680 # endif
3681 #endif
3682
3683 if (val >= 0)
3684 return startpos;
3685
3686 if (val == -2)
3687 return -2;
3688
3689 advance:
3690 if (!range)
3691 break;
3692 else if (range > 0)
3693 {
3694 range--;
3695 startpos++;
3696 }
3697 else
3698 {
3699 range++;
3700 startpos--;
3701 }
3702 }
3703 return -1;
3704 } /* re_search_2 */
3705 #ifdef _LIBC
3706 weak_alias (__re_search_2, re_search_2)
3707 #endif
3708
3709 /* This converts PTR, a pointer into one of the search strings `string1'
3710 and `string2' into an offset from the beginning of that string. */
3711 #define POINTER_TO_OFFSET(ptr) \
3712 (FIRST_STRING_P (ptr) \
3713 ? ((regoff_t) ((ptr) - string1)) \
3714 : ((regoff_t) ((ptr) - string2 + size1)))
3715
3716 /* Macros for dealing with the split strings in re_match_2. */
3717
3718 #define MATCHING_IN_FIRST_STRING (dend == end_match_1)
3719
3720 /* Call before fetching a character with *d. This switches over to
3721 string2 if necessary. */
3722 #define PREFETCH() \
3723 while (d == dend) \
3724 { \
3725 /* End of string2 => fail. */ \
3726 if (dend == end_match_2) \
3727 goto fail; \
3728 /* End of string1 => advance to string2. */ \
3729 d = string2; \
3730 dend = end_match_2; \
3731 }
3732
3733
3734 /* Test if at very beginning or at very end of the virtual concatenation
3735 of `string1' and `string2'. If only one string, it's `string2'. */
3736 #define AT_STRINGS_BEG(d) ((d) == (size1 ? string1 : string2) || !size2)
3737 #define AT_STRINGS_END(d) ((d) == end2)
3738
3739
3740 /* Test if D points to a character which is word-constituent. We have
3741 two special cases to check for: if past the end of string1, look at
3742 the first character in string2; and if before the beginning of
3743 string2, look at the last character in string1. */
3744 #define WORDCHAR_P(d) \
3745 (SYNTAX ((d) == end1 ? *string2 \
3746 : (d) == string2 - 1 ? *(end1 - 1) : *(d)) \
3747 == Sword)
3748
3749 /* Disabled due to a compiler bug -- see comment at case wordbound */
3750 #if 0
3751 /* Test if the character before D and the one at D differ with respect
3752 to being word-constituent. */
3753 #define AT_WORD_BOUNDARY(d) \
3754 (AT_STRINGS_BEG (d) || AT_STRINGS_END (d) \
3755 || WORDCHAR_P (d - 1) != WORDCHAR_P (d))
3756 #endif
3757
3758 /* Free everything we malloc. */
3759 #ifdef MATCH_MAY_ALLOCATE
3760 # define FREE_VAR(var) if (var) REGEX_FREE (var); var = NULL
3761 # define FREE_VARIABLES() \
3762 do { \
3763 REGEX_FREE_STACK (fail_stack.stack); \
3764 FREE_VAR (regstart); \
3765 FREE_VAR (regend); \
3766 FREE_VAR (old_regstart); \
3767 FREE_VAR (old_regend); \
3768 FREE_VAR (best_regstart); \
3769 FREE_VAR (best_regend); \
3770 FREE_VAR (reg_info); \
3771 FREE_VAR (reg_dummy); \
3772 FREE_VAR (reg_info_dummy); \
3773 } while (0)
3774 #else
3775 # define FREE_VARIABLES() ((void)0) /* Do nothing! But inhibit gcc warning. */
3776 #endif /* not MATCH_MAY_ALLOCATE */
3777
3778 /* These values must meet several constraints. They must not be valid
3779 register values; since we have a limit of 255 registers (because
3780 we use only one byte in the pattern for the register number), we can
3781 use numbers larger than 255. They must differ by 1, because of
3782 NUM_FAILURE_ITEMS above. And the value for the lowest register must
3783 be larger than the value for the highest register, so we do not try
3784 to actually save any registers when none are active. */
3785 #define NO_HIGHEST_ACTIVE_REG (1 << BYTEWIDTH)
3786 #define NO_LOWEST_ACTIVE_REG (NO_HIGHEST_ACTIVE_REG + 1)
3787
3788 /* Matching routines. */
3789
3790 #ifndef emacs /* Emacs never uses this. */
3791 /* re_match is like re_match_2 except it takes only a single string. */
3792
3793 int
3794 re_match (bufp, string, size, pos, regs)
3795 struct re_pattern_buffer *bufp;
3796 const char *string;
3797 int size, pos;
3798 struct re_registers *regs;
3799 {
3800 int result = re_match_2_internal (bufp, NULL, 0, string, size,
3801 pos, regs, size);
3802 # ifndef REGEX_MALLOC
3803 # ifdef C_ALLOCA
3804 alloca (0);
3805 # endif
3806 # endif
3807 return result;
3808 }
3809 # ifdef _LIBC
3810 weak_alias (__re_match, re_match)
3811 # endif
3812 #endif /* not emacs */
3813
3814 static boolean group_match_null_string_p _RE_ARGS ((unsigned char **p,
3815 unsigned char *end,
3816 register_info_type *reg_info));
3817 static boolean alt_match_null_string_p _RE_ARGS ((unsigned char *p,
3818 unsigned char *end,
3819 register_info_type *reg_info));
3820 static boolean common_op_match_null_string_p _RE_ARGS ((unsigned char **p,
3821 unsigned char *end,
3822 register_info_type *reg_info));
3823 static int bcmp_translate _RE_ARGS ((const char *s1, const char *s2,
3824 int len, char *translate));
3825
3826 /* re_match_2 matches the compiled pattern in BUFP against the
3827 the (virtual) concatenation of STRING1 and STRING2 (of length SIZE1
3828 and SIZE2, respectively). We start matching at POS, and stop
3829 matching at STOP.
3830
3831 If REGS is non-null and the `no_sub' field of BUFP is nonzero, we
3832 store offsets for the substring each group matched in REGS. See the
3833 documentation for exactly how many groups we fill.
3834
3835 We return -1 if no match, -2 if an internal error (such as the
3836 failure stack overflowing). Otherwise, we return the length of the
3837 matched substring. */
3838
3839 int
3840 re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
3841 struct re_pattern_buffer *bufp;
3842 const char *string1, *string2;
3843 int size1, size2;
3844 int pos;
3845 struct re_registers *regs;
3846 int stop;
3847 {
3848 int result = re_match_2_internal (bufp, string1, size1, string2, size2,
3849 pos, regs, stop);
3850 #ifndef REGEX_MALLOC
3851 # ifdef C_ALLOCA
3852 alloca (0);
3853 # endif
3854 #endif
3855 return result;
3856 }
3857 #ifdef _LIBC
3858 weak_alias (__re_match_2, re_match_2)
3859 #endif
3860
3861 /* This is a separate function so that we can force an alloca cleanup
3862 afterwards. */
3863 static int
3864 re_match_2_internal (bufp, string1, size1, string2, size2, pos, regs, stop)
3865 struct re_pattern_buffer *bufp;
3866 const char *string1, *string2;
3867 int size1, size2;
3868 int pos;
3869 struct re_registers *regs;
3870 int stop;
3871 {
3872 /* General temporaries. */
3873 int mcnt;
3874 unsigned char *p1;
3875
3876 /* Just past the end of the corresponding string. */
3877 const char *end1, *end2;
3878
3879 /* Pointers into string1 and string2, just past the last characters in
3880 each to consider matching. */
3881 const char *end_match_1, *end_match_2;
3882
3883 /* Where we are in the data, and the end of the current string. */
3884 const char *d, *dend;
3885
3886 /* Where we are in the pattern, and the end of the pattern. */
3887 unsigned char *p = bufp->buffer;
3888 register unsigned char *pend = p + bufp->used;
3889
3890 /* Mark the opcode just after a start_memory, so we can test for an
3891 empty subpattern when we get to the stop_memory. */
3892 unsigned char *just_past_start_mem = 0;
3893
3894 /* We use this to map every character in the string. */
3895 RE_TRANSLATE_TYPE translate = bufp->translate;
3896
3897 /* Failure point stack. Each place that can handle a failure further
3898 down the line pushes a failure point on this stack. It consists of
3899 restart, regend, and reg_info for all registers corresponding to
3900 the subexpressions we're currently inside, plus the number of such
3901 registers, and, finally, two char *'s. The first char * is where
3902 to resume scanning the pattern; the second one is where to resume
3903 scanning the strings. If the latter is zero, the failure point is
3904 a ``dummy''; if a failure happens and the failure point is a dummy,
3905 it gets discarded and the next next one is tried. */
3906 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
3907 fail_stack_type fail_stack;
3908 #endif
3909 #ifdef DEBUG
3910 static unsigned failure_id;
3911 unsigned nfailure_points_pushed = 0, nfailure_points_popped = 0;
3912 #endif
3913
3914 #ifdef REL_ALLOC
3915 /* This holds the pointer to the failure stack, when
3916 it is allocated relocatably. */
3917 fail_stack_elt_t *failure_stack_ptr;
3918 #endif
3919
3920 /* We fill all the registers internally, independent of what we
3921 return, for use in backreferences. The number here includes
3922 an element for register zero. */
3923 size_t num_regs = bufp->re_nsub + 1;
3924
3925 /* The currently active registers. */
3926 active_reg_t lowest_active_reg = NO_LOWEST_ACTIVE_REG;
3927 active_reg_t highest_active_reg = NO_HIGHEST_ACTIVE_REG;
3928
3929 /* Information on the contents of registers. These are pointers into
3930 the input strings; they record just what was matched (on this
3931 attempt) by a subexpression part of the pattern, that is, the
3932 regnum-th regstart pointer points to where in the pattern we began
3933 matching and the regnum-th regend points to right after where we
3934 stopped matching the regnum-th subexpression. (The zeroth register
3935 keeps track of what the whole pattern matches.) */
3936 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3937 const char **regstart, **regend;
3938 #endif
3939
3940 /* If a group that's operated upon by a repetition operator fails to
3941 match anything, then the register for its start will need to be
3942 restored because it will have been set to wherever in the string we
3943 are when we last see its open-group operator. Similarly for a
3944 register's end. */
3945 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3946 const char **old_regstart, **old_regend;
3947 #endif
3948
3949 /* The is_active field of reg_info helps us keep track of which (possibly
3950 nested) subexpressions we are currently in. The matched_something
3951 field of reg_info[reg_num] helps us tell whether or not we have
3952 matched any of the pattern so far this time through the reg_num-th
3953 subexpression. These two fields get reset each time through any
3954 loop their register is in. */
3955 #ifdef MATCH_MAY_ALLOCATE /* otherwise, this is global. */
3956 register_info_type *reg_info;
3957 #endif
3958
3959 /* The following record the register info as found in the above
3960 variables when we find a match better than any we've seen before.
3961 This happens as we backtrack through the failure points, which in
3962 turn happens only if we have not yet matched the entire string. */
3963 unsigned best_regs_set = false;
3964 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3965 const char **best_regstart, **best_regend;
3966 #endif
3967
3968 /* Logically, this is `best_regend[0]'. But we don't want to have to
3969 allocate space for that if we're not allocating space for anything
3970 else (see below). Also, we never need info about register 0 for
3971 any of the other register vectors, and it seems rather a kludge to
3972 treat `best_regend' differently than the rest. So we keep track of
3973 the end of the best match so far in a separate variable. We
3974 initialize this to NULL so that when we backtrack the first time
3975 and need to test it, it's not garbage. */
3976 const char *match_end = NULL;
3977
3978 /* This helps SET_REGS_MATCHED avoid doing redundant work. */
3979 int set_regs_matched_done = 0;
3980
3981 /* Used when we pop values we don't care about. */
3982 #ifdef MATCH_MAY_ALLOCATE /* otherwise, these are global. */
3983 const char **reg_dummy;
3984 register_info_type *reg_info_dummy;
3985 #endif
3986
3987 #ifdef DEBUG
3988 /* Counts the total number of registers pushed. */
3989 unsigned num_regs_pushed = 0;
3990 #endif
3991
3992 DEBUG_PRINT1 ("\n\nEntering re_match_2.\n");
3993
3994 INIT_FAIL_STACK ();
3995
3996 #ifdef MATCH_MAY_ALLOCATE
3997 /* Do not bother to initialize all the register variables if there are
3998 no groups in the pattern, as it takes a fair amount of time. If
3999 there are groups, we include space for register 0 (the whole
4000 pattern), even though we never use it, since it simplifies the
4001 array indexing. We should fix this. */
4002 if (bufp->re_nsub)
4003 {
4004 regstart = REGEX_TALLOC (num_regs, const char *);
4005 regend = REGEX_TALLOC (num_regs, const char *);
4006 old_regstart = REGEX_TALLOC (num_regs, const char *);
4007 old_regend = REGEX_TALLOC (num_regs, const char *);
4008 best_regstart = REGEX_TALLOC (num_regs, const char *);
4009 best_regend = REGEX_TALLOC (num_regs, const char *);
4010 reg_info = REGEX_TALLOC (num_regs, register_info_type);
4011 reg_dummy = REGEX_TALLOC (num_regs, const char *);
4012 reg_info_dummy = REGEX_TALLOC (num_regs, register_info_type);
4013
4014 if (!(regstart && regend && old_regstart && old_regend && reg_info
4015 && best_regstart && best_regend && reg_dummy && reg_info_dummy))
4016 {
4017 FREE_VARIABLES ();
4018 return -2;
4019 }
4020 }
4021 else
4022 {
4023 /* We must initialize all our variables to NULL, so that
4024 `FREE_VARIABLES' doesn't try to free them. */
4025 regstart = regend = old_regstart = old_regend = best_regstart
4026 = best_regend = reg_dummy = NULL;
4027 reg_info = reg_info_dummy = (register_info_type *) NULL;
4028 }
4029 #endif /* MATCH_MAY_ALLOCATE */
4030
4031 /* The starting position is bogus. */
4032 if (pos < 0 || pos > size1 + size2)
4033 {
4034 FREE_VARIABLES ();
4035 return -1;
4036 }
4037
4038 /* Initialize subexpression text positions to -1 to mark ones that no
4039 start_memory/stop_memory has been seen for. Also initialize the
4040 register information struct. */
4041 for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++)
4042 {
4043 regstart[mcnt] = regend[mcnt]
4044 = old_regstart[mcnt] = old_regend[mcnt] = REG_UNSET_VALUE;
4045
4046 REG_MATCH_NULL_STRING_P (reg_info[mcnt]) = MATCH_NULL_UNSET_VALUE;
4047 IS_ACTIVE (reg_info[mcnt]) = 0;
4048 MATCHED_SOMETHING (reg_info[mcnt]) = 0;
4049 EVER_MATCHED_SOMETHING (reg_info[mcnt]) = 0;
4050 }
4051
4052 /* We move `string1' into `string2' if the latter's empty -- but not if
4053 `string1' is null. */
4054 if (size2 == 0 && string1 != NULL)
4055 {
4056 string2 = string1;
4057 size2 = size1;
4058 string1 = 0;
4059 size1 = 0;
4060 }
4061 end1 = string1 + size1;
4062 end2 = string2 + size2;
4063
4064 /* Compute where to stop matching, within the two strings. */
4065 if (stop <= size1)
4066 {
4067 end_match_1 = string1 + stop;
4068 end_match_2 = string2;
4069 }
4070 else
4071 {
4072 end_match_1 = end1;
4073 end_match_2 = string2 + stop - size1;
4074 }
4075
4076 /* `p' scans through the pattern as `d' scans through the data.
4077 `dend' is the end of the input string that `d' points within. `d'
4078 is advanced into the following input string whenever necessary, but
4079 this happens before fetching; therefore, at the beginning of the
4080 loop, `d' can be pointing at the end of a string, but it cannot
4081 equal `string2'. */
4082 if (size1 > 0 && pos <= size1)
4083 {
4084 d = string1 + pos;
4085 dend = end_match_1;
4086 }
4087 else
4088 {
4089 d = string2 + pos - size1;
4090 dend = end_match_2;
4091 }
4092
4093 DEBUG_PRINT1 ("The compiled pattern is:\n");
4094 DEBUG_PRINT_COMPILED_PATTERN (bufp, p, pend);
4095 DEBUG_PRINT1 ("The string to match is: `");
4096 DEBUG_PRINT_DOUBLE_STRING (d, string1, size1, string2, size2);
4097 DEBUG_PRINT1 ("'\n");
4098
4099 /* This loops over pattern commands. It exits by returning from the
4100 function if the match is complete, or it drops through if the match
4101 fails at this starting point in the input data. */
4102 for (;;)
4103 {
4104 #ifdef _LIBC
4105 DEBUG_PRINT2 ("\n%p: ", p);
4106 #else
4107 DEBUG_PRINT2 ("\n0x%x: ", p);
4108 #endif
4109
4110 if (p == pend)
4111 { /* End of pattern means we might have succeeded. */
4112 DEBUG_PRINT1 ("end of pattern ... ");
4113
4114 /* If we haven't matched the entire string, and we want the
4115 longest match, try backtracking. */
4116 if (d != end_match_2)
4117 {
4118 /* 1 if this match ends in the same string (string1 or string2)
4119 as the best previous match. */
4120 boolean same_str_p = (FIRST_STRING_P (match_end)
4121 == MATCHING_IN_FIRST_STRING);
4122 /* 1 if this match is the best seen so far. */
4123 boolean best_match_p;
4124
4125 /* AIX compiler got confused when this was combined
4126 with the previous declaration. */
4127 if (same_str_p)
4128 best_match_p = d > match_end;
4129 else
4130 best_match_p = !MATCHING_IN_FIRST_STRING;
4131
4132 DEBUG_PRINT1 ("backtracking.\n");
4133
4134 if (!FAIL_STACK_EMPTY ())
4135 { /* More failure points to try. */
4136
4137 /* If exceeds best match so far, save it. */
4138 if (!best_regs_set || best_match_p)
4139 {
4140 best_regs_set = true;
4141 match_end = d;
4142
4143 DEBUG_PRINT1 ("\nSAVING match as best so far.\n");
4144
4145 for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++)
4146 {
4147 best_regstart[mcnt] = regstart[mcnt];
4148 best_regend[mcnt] = regend[mcnt];
4149 }
4150 }
4151 goto fail;
4152 }
4153
4154 /* If no failure points, don't restore garbage. And if
4155 last match is real best match, don't restore second
4156 best one. */
4157 else if (best_regs_set && !best_match_p)
4158 {
4159 restore_best_regs:
4160 /* Restore best match. It may happen that `dend ==
4161 end_match_1' while the restored d is in string2.
4162 For example, the pattern `x.*y.*z' against the
4163 strings `x-' and `y-z-', if the two strings are
4164 not consecutive in memory. */
4165 DEBUG_PRINT1 ("Restoring best registers.\n");
4166
4167 d = match_end;
4168 dend = ((d >= string1 && d <= end1)
4169 ? end_match_1 : end_match_2);
4170
4171 for (mcnt = 1; (unsigned) mcnt < num_regs; mcnt++)
4172 {
4173 regstart[mcnt] = best_regstart[mcnt];
4174 regend[mcnt] = best_regend[mcnt];
4175 }
4176 }
4177 } /* d != end_match_2 */
4178
4179 succeed_label:
4180 DEBUG_PRINT1 ("Accepting match.\n");
4181
4182 /* If caller wants register contents data back, do it. */
4183 if (regs && !bufp->no_sub)
4184 {
4185 /* Have the register data arrays been allocated? */
4186 if (bufp->regs_allocated == REGS_UNALLOCATED)
4187 { /* No. So allocate them with malloc. We need one
4188 extra element beyond `num_regs' for the `-1' marker
4189 GNU code uses. */
4190 regs->num_regs = MAX (RE_NREGS, num_regs + 1);
4191 regs->start = TALLOC (regs->num_regs, regoff_t);
4192 regs->end = TALLOC (regs->num_regs, regoff_t);
4193 if (regs->start == NULL || regs->end == NULL)
4194 {
4195 FREE_VARIABLES ();
4196 return -2;
4197 }
4198 bufp->regs_allocated = REGS_REALLOCATE;
4199 }
4200 else if (bufp->regs_allocated == REGS_REALLOCATE)
4201 { /* Yes. If we need more elements than were already
4202 allocated, reallocate them. If we need fewer, just
4203 leave it alone. */
4204 if (regs->num_regs < num_regs + 1)
4205 {
4206 regs->num_regs = num_regs + 1;
4207 RETALLOC (regs->start, regs->num_regs, regoff_t);
4208 RETALLOC (regs->end, regs->num_regs, regoff_t);
4209 if (regs->start == NULL || regs->end == NULL)
4210 {
4211 FREE_VARIABLES ();
4212 return -2;
4213 }
4214 }
4215 }
4216 else
4217 {
4218 /* These braces fend off a "empty body in an else-statement"
4219 warning under GCC when assert expands to nothing. */
4220 assert (bufp->regs_allocated == REGS_FIXED);
4221 }
4222
4223 /* Convert the pointer data in `regstart' and `regend' to
4224 indices. Register zero has to be set differently,
4225 since we haven't kept track of any info for it. */
4226 if (regs->num_regs > 0)
4227 {
4228 regs->start[0] = pos;
4229 regs->end[0] = (MATCHING_IN_FIRST_STRING
4230 ? ((regoff_t) (d - string1))
4231 : ((regoff_t) (d - string2 + size1)));
4232 }
4233
4234 /* Go through the first `min (num_regs, regs->num_regs)'
4235 registers, since that is all we initialized. */
4236 for (mcnt = 1; (unsigned) mcnt < MIN (num_regs, regs->num_regs);
4237 mcnt++)
4238 {
4239 if (REG_UNSET (regstart[mcnt]) || REG_UNSET (regend[mcnt]))
4240 regs->start[mcnt] = regs->end[mcnt] = -1;
4241 else
4242 {
4243 regs->start[mcnt]
4244 = (regoff_t) POINTER_TO_OFFSET (regstart[mcnt]);
4245 regs->end[mcnt]
4246 = (regoff_t) POINTER_TO_OFFSET (regend[mcnt]);
4247 }
4248 }
4249
4250 /* If the regs structure we return has more elements than
4251 were in the pattern, set the extra elements to -1. If
4252 we (re)allocated the registers, this is the case,
4253 because we always allocate enough to have at least one
4254 -1 at the end. */
4255 for (mcnt = num_regs; (unsigned) mcnt < regs->num_regs; mcnt++)
4256 regs->start[mcnt] = regs->end[mcnt] = -1;
4257 } /* regs && !bufp->no_sub */
4258
4259 DEBUG_PRINT4 ("%u failure points pushed, %u popped (%u remain).\n",
4260 nfailure_points_pushed, nfailure_points_popped,
4261 nfailure_points_pushed - nfailure_points_popped);
4262 DEBUG_PRINT2 ("%u registers pushed.\n", num_regs_pushed);
4263
4264 mcnt = d - pos - (MATCHING_IN_FIRST_STRING
4265 ? string1
4266 : string2 - size1);
4267
4268 DEBUG_PRINT2 ("Returning %d from re_match_2.\n", mcnt);
4269
4270 FREE_VARIABLES ();
4271 return mcnt;
4272 }
4273
4274 /* Otherwise match next pattern command. */
4275 switch (SWITCH_ENUM_CAST ((re_opcode_t) *p++))
4276 {
4277 /* Ignore these. Used to ignore the n of succeed_n's which
4278 currently have n == 0. */
4279 case no_op:
4280 DEBUG_PRINT1 ("EXECUTING no_op.\n");
4281 break;
4282
4283 case succeed:
4284 DEBUG_PRINT1 ("EXECUTING succeed.\n");
4285 goto succeed_label;
4286
4287 /* Match the next n pattern characters exactly. The following
4288 byte in the pattern defines n, and the n bytes after that
4289 are the characters to match. */
4290 case exactn:
4291 mcnt = *p++;
4292 DEBUG_PRINT2 ("EXECUTING exactn %d.\n", mcnt);
4293
4294 /* This is written out as an if-else so we don't waste time
4295 testing `translate' inside the loop. */
4296 if (translate)
4297 {
4298 do
4299 {
4300 PREFETCH ();
4301 if ((unsigned char) translate[(unsigned char) *d++]
4302 != (unsigned char) *p++)
4303 goto fail;
4304 }
4305 while (--mcnt);
4306 }
4307 else
4308 {
4309 do
4310 {
4311 PREFETCH ();
4312 if (*d++ != (char) *p++) goto fail;
4313 }
4314 while (--mcnt);
4315 }
4316 SET_REGS_MATCHED ();
4317 break;
4318
4319
4320 /* Match any character except possibly a newline or a null. */
4321 case anychar:
4322 DEBUG_PRINT1 ("EXECUTING anychar.\n");
4323
4324 PREFETCH ();
4325
4326 if ((!(bufp->syntax & RE_DOT_NEWLINE) && TRANSLATE (*d) == '\n')
4327 || (bufp->syntax & RE_DOT_NOT_NULL && TRANSLATE (*d) == '\000'))
4328 goto fail;
4329
4330 SET_REGS_MATCHED ();
4331 DEBUG_PRINT2 (" Matched `%d'.\n", *d);
4332 d++;
4333 break;
4334
4335
4336 case charset:
4337 case charset_not:
4338 {
4339 register unsigned char c;
4340 boolean not = (re_opcode_t) *(p - 1) == charset_not;
4341
4342 DEBUG_PRINT2 ("EXECUTING charset%s.\n", not ? "_not" : "");
4343
4344 PREFETCH ();
4345 c = TRANSLATE (*d); /* The character to match. */
4346
4347 /* Cast to `unsigned' instead of `unsigned char' in case the
4348 bit list is a full 32 bytes long. */
4349 if (c < (unsigned) (*p * BYTEWIDTH)
4350 && p[1 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4351 not = !not;
4352
4353 p += 1 + *p;
4354
4355 if (!not) goto fail;
4356
4357 SET_REGS_MATCHED ();
4358 d++;
4359 break;
4360 }
4361
4362
4363 /* The beginning of a group is represented by start_memory.
4364 The arguments are the register number in the next byte, and the
4365 number of groups inner to this one in the next. The text
4366 matched within the group is recorded (in the internal
4367 registers data structure) under the register number. */
4368 case start_memory:
4369 DEBUG_PRINT3 ("EXECUTING start_memory %d (%d):\n", *p, p[1]);
4370
4371 /* Find out if this group can match the empty string. */
4372 p1 = p; /* To send to group_match_null_string_p. */
4373
4374 if (REG_MATCH_NULL_STRING_P (reg_info[*p]) == MATCH_NULL_UNSET_VALUE)
4375 REG_MATCH_NULL_STRING_P (reg_info[*p])
4376 = group_match_null_string_p (&p1, pend, reg_info);
4377
4378 /* Save the position in the string where we were the last time
4379 we were at this open-group operator in case the group is
4380 operated upon by a repetition operator, e.g., with `(a*)*b'
4381 against `ab'; then we want to ignore where we are now in
4382 the string in case this attempt to match fails. */
4383 old_regstart[*p] = REG_MATCH_NULL_STRING_P (reg_info[*p])
4384 ? REG_UNSET (regstart[*p]) ? d : regstart[*p]
4385 : regstart[*p];
4386 DEBUG_PRINT2 (" old_regstart: %d\n",
4387 POINTER_TO_OFFSET (old_regstart[*p]));
4388
4389 regstart[*p] = d;
4390 DEBUG_PRINT2 (" regstart: %d\n", POINTER_TO_OFFSET (regstart[*p]));
4391
4392 IS_ACTIVE (reg_info[*p]) = 1;
4393 MATCHED_SOMETHING (reg_info[*p]) = 0;
4394
4395 /* Clear this whenever we change the register activity status. */
4396 set_regs_matched_done = 0;
4397
4398 /* This is the new highest active register. */
4399 highest_active_reg = *p;
4400
4401 /* If nothing was active before, this is the new lowest active
4402 register. */
4403 if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
4404 lowest_active_reg = *p;
4405
4406 /* Move past the register number and inner group count. */
4407 p += 2;
4408 just_past_start_mem = p;
4409
4410 break;
4411
4412
4413 /* The stop_memory opcode represents the end of a group. Its
4414 arguments are the same as start_memory's: the register
4415 number, and the number of inner groups. */
4416 case stop_memory:
4417 DEBUG_PRINT3 ("EXECUTING stop_memory %d (%d):\n", *p, p[1]);
4418
4419 /* We need to save the string position the last time we were at
4420 this close-group operator in case the group is operated
4421 upon by a repetition operator, e.g., with `((a*)*(b*)*)*'
4422 against `aba'; then we want to ignore where we are now in
4423 the string in case this attempt to match fails. */
4424 old_regend[*p] = REG_MATCH_NULL_STRING_P (reg_info[*p])
4425 ? REG_UNSET (regend[*p]) ? d : regend[*p]
4426 : regend[*p];
4427 DEBUG_PRINT2 (" old_regend: %d\n",
4428 POINTER_TO_OFFSET (old_regend[*p]));
4429
4430 regend[*p] = d;
4431 DEBUG_PRINT2 (" regend: %d\n", POINTER_TO_OFFSET (regend[*p]));
4432
4433 /* This register isn't active anymore. */
4434 IS_ACTIVE (reg_info[*p]) = 0;
4435
4436 /* Clear this whenever we change the register activity status. */
4437 set_regs_matched_done = 0;
4438
4439 /* If this was the only register active, nothing is active
4440 anymore. */
4441 if (lowest_active_reg == highest_active_reg)
4442 {
4443 lowest_active_reg = NO_LOWEST_ACTIVE_REG;
4444 highest_active_reg = NO_HIGHEST_ACTIVE_REG;
4445 }
4446 else
4447 { /* We must scan for the new highest active register, since
4448 it isn't necessarily one less than now: consider
4449 (a(b)c(d(e)f)g). When group 3 ends, after the f), the
4450 new highest active register is 1. */
4451 unsigned char r = *p - 1;
4452 while (r > 0 && !IS_ACTIVE (reg_info[r]))
4453 r--;
4454
4455 /* If we end up at register zero, that means that we saved
4456 the registers as the result of an `on_failure_jump', not
4457 a `start_memory', and we jumped to past the innermost
4458 `stop_memory'. For example, in ((.)*) we save
4459 registers 1 and 2 as a result of the *, but when we pop
4460 back to the second ), we are at the stop_memory 1.
4461 Thus, nothing is active. */
4462 if (r == 0)
4463 {
4464 lowest_active_reg = NO_LOWEST_ACTIVE_REG;
4465 highest_active_reg = NO_HIGHEST_ACTIVE_REG;
4466 }
4467 else
4468 highest_active_reg = r;
4469 }
4470
4471 /* If just failed to match something this time around with a
4472 group that's operated on by a repetition operator, try to
4473 force exit from the ``loop'', and restore the register
4474 information for this group that we had before trying this
4475 last match. */
4476 if ((!MATCHED_SOMETHING (reg_info[*p])
4477 || just_past_start_mem == p - 1)
4478 && (p + 2) < pend)
4479 {
4480 boolean is_a_jump_n = false;
4481
4482 p1 = p + 2;
4483 mcnt = 0;
4484 switch ((re_opcode_t) *p1++)
4485 {
4486 case jump_n:
4487 is_a_jump_n = true;
4488 case pop_failure_jump:
4489 case maybe_pop_jump:
4490 case jump:
4491 case dummy_failure_jump:
4492 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4493 if (is_a_jump_n)
4494 p1 += 2;
4495 break;
4496
4497 default:
4498 /* do nothing */ ;
4499 }
4500 p1 += mcnt;
4501
4502 /* If the next operation is a jump backwards in the pattern
4503 to an on_failure_jump right before the start_memory
4504 corresponding to this stop_memory, exit from the loop
4505 by forcing a failure after pushing on the stack the
4506 on_failure_jump's jump in the pattern, and d. */
4507 if (mcnt < 0 && (re_opcode_t) *p1 == on_failure_jump
4508 && (re_opcode_t) p1[3] == start_memory && p1[4] == *p)
4509 {
4510 /* If this group ever matched anything, then restore
4511 what its registers were before trying this last
4512 failed match, e.g., with `(a*)*b' against `ab' for
4513 regstart[1], and, e.g., with `((a*)*(b*)*)*'
4514 against `aba' for regend[3].
4515
4516 Also restore the registers for inner groups for,
4517 e.g., `((a*)(b*))*' against `aba' (register 3 would
4518 otherwise get trashed). */
4519
4520 if (EVER_MATCHED_SOMETHING (reg_info[*p]))
4521 {
4522 unsigned r;
4523
4524 EVER_MATCHED_SOMETHING (reg_info[*p]) = 0;
4525
4526 /* Restore this and inner groups' (if any) registers. */
4527 for (r = *p; r < (unsigned) *p + (unsigned) *(p + 1);
4528 r++)
4529 {
4530 regstart[r] = old_regstart[r];
4531
4532 /* xx why this test? */
4533 if (old_regend[r] >= regstart[r])
4534 regend[r] = old_regend[r];
4535 }
4536 }
4537 p1++;
4538 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
4539 PUSH_FAILURE_POINT (p1 + mcnt, d, -2);
4540
4541 goto fail;
4542 }
4543 }
4544
4545 /* Move past the register number and the inner group count. */
4546 p += 2;
4547 break;
4548
4549
4550 /* \<digit> has been turned into a `duplicate' command which is
4551 followed by the numeric value of <digit> as the register number. */
4552 case duplicate:
4553 {
4554 register const char *d2, *dend2;
4555 int regno = *p++; /* Get which register to match against. */
4556 DEBUG_PRINT2 ("EXECUTING duplicate %d.\n", regno);
4557
4558 /* Can't back reference a group which we've never matched. */
4559 if (REG_UNSET (regstart[regno]) || REG_UNSET (regend[regno]))
4560 goto fail;
4561
4562 /* Where in input to try to start matching. */
4563 d2 = regstart[regno];
4564
4565 /* Where to stop matching; if both the place to start and
4566 the place to stop matching are in the same string, then
4567 set to the place to stop, otherwise, for now have to use
4568 the end of the first string. */
4569
4570 dend2 = ((FIRST_STRING_P (regstart[regno])
4571 == FIRST_STRING_P (regend[regno]))
4572 ? regend[regno] : end_match_1);
4573 for (;;)
4574 {
4575 /* If necessary, advance to next segment in register
4576 contents. */
4577 while (d2 == dend2)
4578 {
4579 if (dend2 == end_match_2) break;
4580 if (dend2 == regend[regno]) break;
4581
4582 /* End of string1 => advance to string2. */
4583 d2 = string2;
4584 dend2 = regend[regno];
4585 }
4586 /* At end of register contents => success */
4587 if (d2 == dend2) break;
4588
4589 /* If necessary, advance to next segment in data. */
4590 PREFETCH ();
4591
4592 /* How many characters left in this segment to match. */
4593 mcnt = dend - d;
4594
4595 /* Want how many consecutive characters we can match in
4596 one shot, so, if necessary, adjust the count. */
4597 if (mcnt > dend2 - d2)
4598 mcnt = dend2 - d2;
4599
4600 /* Compare that many; failure if mismatch, else move
4601 past them. */
4602 if (translate
4603 ? bcmp_translate (d, d2, mcnt, translate)
4604 : memcmp (d, d2, mcnt))
4605 goto fail;
4606 d += mcnt, d2 += mcnt;
4607
4608 /* Do this because we've match some characters. */
4609 SET_REGS_MATCHED ();
4610 }
4611 }
4612 break;
4613
4614
4615 /* begline matches the empty string at the beginning of the string
4616 (unless `not_bol' is set in `bufp'), and, if
4617 `newline_anchor' is set, after newlines. */
4618 case begline:
4619 DEBUG_PRINT1 ("EXECUTING begline.\n");
4620
4621 if (AT_STRINGS_BEG (d))
4622 {
4623 if (!bufp->not_bol) break;
4624 }
4625 else if (d[-1] == '\n' && bufp->newline_anchor)
4626 {
4627 break;
4628 }
4629 /* In all other cases, we fail. */
4630 goto fail;
4631
4632
4633 /* endline is the dual of begline. */
4634 case endline:
4635 DEBUG_PRINT1 ("EXECUTING endline.\n");
4636
4637 if (AT_STRINGS_END (d))
4638 {
4639 if (!bufp->not_eol) break;
4640 }
4641
4642 /* We have to ``prefetch'' the next character. */
4643 else if ((d == end1 ? *string2 : *d) == '\n'
4644 && bufp->newline_anchor)
4645 {
4646 break;
4647 }
4648 goto fail;
4649
4650
4651 /* Match at the very beginning of the data. */
4652 case begbuf:
4653 DEBUG_PRINT1 ("EXECUTING begbuf.\n");
4654 if (AT_STRINGS_BEG (d))
4655 break;
4656 goto fail;
4657
4658
4659 /* Match at the very end of the data. */
4660 case endbuf:
4661 DEBUG_PRINT1 ("EXECUTING endbuf.\n");
4662 if (AT_STRINGS_END (d))
4663 break;
4664 goto fail;
4665
4666
4667 /* on_failure_keep_string_jump is used to optimize `.*\n'. It
4668 pushes NULL as the value for the string on the stack. Then
4669 `pop_failure_point' will keep the current value for the
4670 string, instead of restoring it. To see why, consider
4671 matching `foo\nbar' against `.*\n'. The .* matches the foo;
4672 then the . fails against the \n. But the next thing we want
4673 to do is match the \n against the \n; if we restored the
4674 string value, we would be back at the foo.
4675
4676 Because this is used only in specific cases, we don't need to
4677 check all the things that `on_failure_jump' does, to make
4678 sure the right things get saved on the stack. Hence we don't
4679 share its code. The only reason to push anything on the
4680 stack at all is that otherwise we would have to change
4681 `anychar's code to do something besides goto fail in this
4682 case; that seems worse than this. */
4683 case on_failure_keep_string_jump:
4684 DEBUG_PRINT1 ("EXECUTING on_failure_keep_string_jump");
4685
4686 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4687 #ifdef _LIBC
4688 DEBUG_PRINT3 (" %d (to %p):\n", mcnt, p + mcnt);
4689 #else
4690 DEBUG_PRINT3 (" %d (to 0x%x):\n", mcnt, p + mcnt);
4691 #endif
4692
4693 PUSH_FAILURE_POINT (p + mcnt, NULL, -2);
4694 break;
4695
4696
4697 /* Uses of on_failure_jump:
4698
4699 Each alternative starts with an on_failure_jump that points
4700 to the beginning of the next alternative. Each alternative
4701 except the last ends with a jump that in effect jumps past
4702 the rest of the alternatives. (They really jump to the
4703 ending jump of the following alternative, because tensioning
4704 these jumps is a hassle.)
4705
4706 Repeats start with an on_failure_jump that points past both
4707 the repetition text and either the following jump or
4708 pop_failure_jump back to this on_failure_jump. */
4709 case on_failure_jump:
4710 on_failure:
4711 DEBUG_PRINT1 ("EXECUTING on_failure_jump");
4712
4713 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4714 #ifdef _LIBC
4715 DEBUG_PRINT3 (" %d (to %p)", mcnt, p + mcnt);
4716 #else
4717 DEBUG_PRINT3 (" %d (to 0x%x)", mcnt, p + mcnt);
4718 #endif
4719
4720 /* If this on_failure_jump comes right before a group (i.e.,
4721 the original * applied to a group), save the information
4722 for that group and all inner ones, so that if we fail back
4723 to this point, the group's information will be correct.
4724 For example, in \(a*\)*\1, we need the preceding group,
4725 and in \(zz\(a*\)b*\)\2, we need the inner group. */
4726
4727 /* We can't use `p' to check ahead because we push
4728 a failure point to `p + mcnt' after we do this. */
4729 p1 = p;
4730
4731 /* We need to skip no_op's before we look for the
4732 start_memory in case this on_failure_jump is happening as
4733 the result of a completed succeed_n, as in \(a\)\{1,3\}b\1
4734 against aba. */
4735 while (p1 < pend && (re_opcode_t) *p1 == no_op)
4736 p1++;
4737
4738 if (p1 < pend && (re_opcode_t) *p1 == start_memory)
4739 {
4740 /* We have a new highest active register now. This will
4741 get reset at the start_memory we are about to get to,
4742 but we will have saved all the registers relevant to
4743 this repetition op, as described above. */
4744 highest_active_reg = *(p1 + 1) + *(p1 + 2);
4745 if (lowest_active_reg == NO_LOWEST_ACTIVE_REG)
4746 lowest_active_reg = *(p1 + 1);
4747 }
4748
4749 DEBUG_PRINT1 (":\n");
4750 PUSH_FAILURE_POINT (p + mcnt, d, -2);
4751 break;
4752
4753
4754 /* A smart repeat ends with `maybe_pop_jump'.
4755 We change it to either `pop_failure_jump' or `jump'. */
4756 case maybe_pop_jump:
4757 EXTRACT_NUMBER_AND_INCR (mcnt, p);
4758 DEBUG_PRINT2 ("EXECUTING maybe_pop_jump %d.\n", mcnt);
4759 {
4760 register unsigned char *p2 = p;
4761
4762 /* Compare the beginning of the repeat with what in the
4763 pattern follows its end. If we can establish that there
4764 is nothing that they would both match, i.e., that we
4765 would have to backtrack because of (as in, e.g., `a*a')
4766 then we can change to pop_failure_jump, because we'll
4767 never have to backtrack.
4768
4769 This is not true in the case of alternatives: in
4770 `(a|ab)*' we do need to backtrack to the `ab' alternative
4771 (e.g., if the string was `ab'). But instead of trying to
4772 detect that here, the alternative has put on a dummy
4773 failure point which is what we will end up popping. */
4774
4775 /* Skip over open/close-group commands.
4776 If what follows this loop is a ...+ construct,
4777 look at what begins its body, since we will have to
4778 match at least one of that. */
4779 while (1)
4780 {
4781 if (p2 + 2 < pend
4782 && ((re_opcode_t) *p2 == stop_memory
4783 || (re_opcode_t) *p2 == start_memory))
4784 p2 += 3;
4785 else if (p2 + 6 < pend
4786 && (re_opcode_t) *p2 == dummy_failure_jump)
4787 p2 += 6;
4788 else
4789 break;
4790 }
4791
4792 p1 = p + mcnt;
4793 /* p1[0] ... p1[2] are the `on_failure_jump' corresponding
4794 to the `maybe_finalize_jump' of this case. Examine what
4795 follows. */
4796
4797 /* If we're at the end of the pattern, we can change. */
4798 if (p2 == pend)
4799 {
4800 /* Consider what happens when matching ":\(.*\)"
4801 against ":/". I don't really understand this code
4802 yet. */
4803 p[-3] = (unsigned char) pop_failure_jump;
4804 DEBUG_PRINT1
4805 (" End of pattern: change to `pop_failure_jump'.\n");
4806 }
4807
4808 else if ((re_opcode_t) *p2 == exactn
4809 || (bufp->newline_anchor && (re_opcode_t) *p2 == endline))
4810 {
4811 register unsigned char c
4812 = *p2 == (unsigned char) endline ? '\n' : p2[2];
4813
4814 if ((re_opcode_t) p1[3] == exactn && p1[5] != c)
4815 {
4816 p[-3] = (unsigned char) pop_failure_jump;
4817 DEBUG_PRINT3 (" %c != %c => pop_failure_jump.\n",
4818 c, p1[5]);
4819 }
4820
4821 else if ((re_opcode_t) p1[3] == charset
4822 || (re_opcode_t) p1[3] == charset_not)
4823 {
4824 int not = (re_opcode_t) p1[3] == charset_not;
4825
4826 if (c < (unsigned char) (p1[4] * BYTEWIDTH)
4827 && p1[5 + c / BYTEWIDTH] & (1 << (c % BYTEWIDTH)))
4828 not = !not;
4829
4830 /* `not' is equal to 1 if c would match, which means
4831 that we can't change to pop_failure_jump. */
4832 if (!not)
4833 {
4834 p[-3] = (unsigned char) pop_failure_jump;
4835 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4836 }
4837 }
4838 }
4839 else if ((re_opcode_t) *p2 == charset)
4840 {
4841 /* We win if the first character of the loop is not part
4842 of the charset. */
4843 if ((re_opcode_t) p1[3] == exactn
4844 && ! ((int) p2[1] * BYTEWIDTH > (int) p1[5]
4845 && (p2[2 + p1[5] / BYTEWIDTH]
4846 & (1 << (p1[5] % BYTEWIDTH)))))
4847 {
4848 p[-3] = (unsigned char) pop_failure_jump;
4849 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4850 }
4851
4852 else if ((re_opcode_t) p1[3] == charset_not)
4853 {
4854 int idx;
4855 /* We win if the charset_not inside the loop
4856 lists every character listed in the charset after. */
4857 for (idx = 0; idx < (int) p2[1]; idx++)
4858 if (! (p2[2 + idx] == 0
4859 || (idx < (int) p1[4]
4860 && ((p2[2 + idx] & ~ p1[5 + idx]) == 0))))
4861 break;
4862
4863 if (idx == p2[1])
4864 {
4865 p[-3] = (unsigned char) pop_failure_jump;
4866 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4867 }
4868 }
4869 else if ((re_opcode_t) p1[3] == charset)
4870 {
4871 int idx;
4872 /* We win if the charset inside the loop
4873 has no overlap with the one after the loop. */
4874 for (idx = 0;
4875 idx < (int) p2[1] && idx < (int) p1[4];
4876 idx++)
4877 if ((p2[2 + idx] & p1[5 + idx]) != 0)
4878 break;
4879
4880 if (idx == p2[1] || idx == p1[4])
4881 {
4882 p[-3] = (unsigned char) pop_failure_jump;
4883 DEBUG_PRINT1 (" No match => pop_failure_jump.\n");
4884 }
4885 }
4886 }
4887 }
4888 p -= 2; /* Point at relative address again. */
4889 if ((re_opcode_t) p[-1] != pop_failure_jump)
4890 {
4891 p[-1] = (unsigned char) jump;
4892 DEBUG_PRINT1 (" Match => jump.\n");
4893 goto unconditional_jump;
4894 }
4895 /* Note fall through. */
4896
4897
4898 /* The end of a simple repeat has a pop_failure_jump back to
4899 its matching on_failure_jump, where the latter will push a
4900 failure point. The pop_failure_jump takes off failure
4901 points put on by this pop_failure_jump's matching
4902 on_failure_jump; we got through the pattern to here from the
4903 matching on_failure_jump, so didn't fail. */
4904 case pop_failure_jump:
4905 {
4906 /* We need to pass separate storage for the lowest and
4907 highest registers, even though we don't care about the
4908 actual values. Otherwise, we will restore only one
4909 register from the stack, since lowest will == highest in
4910 `pop_failure_point'. */
4911 active_reg_t dummy_low_reg, dummy_high_reg;
4912 unsigned char *pdummy;
4913 const char *sdummy;
4914
4915 DEBUG_PRINT1 ("EXECUTING pop_failure_jump.\n");
4916 POP_FAILURE_POINT (sdummy, pdummy,
4917 dummy_low_reg, dummy_high_reg,
4918 reg_dummy, reg_dummy, reg_info_dummy);
4919 }
4920 /* Note fall through. */
4921
4922 unconditional_jump:
4923 #ifdef _LIBC
4924 DEBUG_PRINT2 ("\n%p: ", p);
4925 #else
4926 DEBUG_PRINT2 ("\n0x%x: ", p);
4927 #endif
4928 /* Note fall through. */
4929
4930 /* Unconditionally jump (without popping any failure points). */
4931 case jump:
4932 EXTRACT_NUMBER_AND_INCR (mcnt, p); /* Get the amount to jump. */
4933 DEBUG_PRINT2 ("EXECUTING jump %d ", mcnt);
4934 p += mcnt; /* Do the jump. */
4935 #ifdef _LIBC
4936 DEBUG_PRINT2 ("(to %p).\n", p);
4937 #else
4938 DEBUG_PRINT2 ("(to 0x%x).\n", p);
4939 #endif
4940 break;
4941
4942
4943 /* We need this opcode so we can detect where alternatives end
4944 in `group_match_null_string_p' et al. */
4945 case jump_past_alt:
4946 DEBUG_PRINT1 ("EXECUTING jump_past_alt.\n");
4947 goto unconditional_jump;
4948
4949
4950 /* Normally, the on_failure_jump pushes a failure point, which
4951 then gets popped at pop_failure_jump. We will end up at
4952 pop_failure_jump, also, and with a pattern of, say, `a+', we
4953 are skipping over the on_failure_jump, so we have to push
4954 something meaningless for pop_failure_jump to pop. */
4955 case dummy_failure_jump:
4956 DEBUG_PRINT1 ("EXECUTING dummy_failure_jump.\n");
4957 /* It doesn't matter what we push for the string here. What
4958 the code at `fail' tests is the value for the pattern. */
4959 PUSH_FAILURE_POINT (NULL, NULL, -2);
4960 goto unconditional_jump;
4961
4962
4963 /* At the end of an alternative, we need to push a dummy failure
4964 point in case we are followed by a `pop_failure_jump', because
4965 we don't want the failure point for the alternative to be
4966 popped. For example, matching `(a|ab)*' against `aab'
4967 requires that we match the `ab' alternative. */
4968 case push_dummy_failure:
4969 DEBUG_PRINT1 ("EXECUTING push_dummy_failure.\n");
4970 /* See comments just above at `dummy_failure_jump' about the
4971 two zeroes. */
4972 PUSH_FAILURE_POINT (NULL, NULL, -2);
4973 break;
4974
4975 /* Have to succeed matching what follows at least n times.
4976 After that, handle like `on_failure_jump'. */
4977 case succeed_n:
4978 EXTRACT_NUMBER (mcnt, p + 2);
4979 DEBUG_PRINT2 ("EXECUTING succeed_n %d.\n", mcnt);
4980
4981 assert (mcnt >= 0);
4982 /* Originally, this is how many times we HAVE to succeed. */
4983 if (mcnt > 0)
4984 {
4985 mcnt--;
4986 p += 2;
4987 STORE_NUMBER_AND_INCR (p, mcnt);
4988 #ifdef _LIBC
4989 DEBUG_PRINT3 (" Setting %p to %d.\n", p - 2, mcnt);
4990 #else
4991 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p - 2, mcnt);
4992 #endif
4993 }
4994 else if (mcnt == 0)
4995 {
4996 #ifdef _LIBC
4997 DEBUG_PRINT2 (" Setting two bytes from %p to no_op.\n", p+2);
4998 #else
4999 DEBUG_PRINT2 (" Setting two bytes from 0x%x to no_op.\n", p+2);
5000 #endif
5001 p[2] = (unsigned char) no_op;
5002 p[3] = (unsigned char) no_op;
5003 goto on_failure;
5004 }
5005 break;
5006
5007 case jump_n:
5008 EXTRACT_NUMBER (mcnt, p + 2);
5009 DEBUG_PRINT2 ("EXECUTING jump_n %d.\n", mcnt);
5010
5011 /* Originally, this is how many times we CAN jump. */
5012 if (mcnt)
5013 {
5014 mcnt--;
5015 STORE_NUMBER (p + 2, mcnt);
5016 #ifdef _LIBC
5017 DEBUG_PRINT3 (" Setting %p to %d.\n", p + 2, mcnt);
5018 #else
5019 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p + 2, mcnt);
5020 #endif
5021 goto unconditional_jump;
5022 }
5023 /* If don't have to jump any more, skip over the rest of command. */
5024 else
5025 p += 4;
5026 break;
5027
5028 case set_number_at:
5029 {
5030 DEBUG_PRINT1 ("EXECUTING set_number_at.\n");
5031
5032 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5033 p1 = p + mcnt;
5034 EXTRACT_NUMBER_AND_INCR (mcnt, p);
5035 #ifdef _LIBC
5036 DEBUG_PRINT3 (" Setting %p to %d.\n", p1, mcnt);
5037 #else
5038 DEBUG_PRINT3 (" Setting 0x%x to %d.\n", p1, mcnt);
5039 #endif
5040 STORE_NUMBER (p1, mcnt);
5041 break;
5042 }
5043
5044 #if 0
5045 /* The DEC Alpha C compiler 3.x generates incorrect code for the
5046 test WORDCHAR_P (d - 1) != WORDCHAR_P (d) in the expansion of
5047 AT_WORD_BOUNDARY, so this code is disabled. Expanding the
5048 macro and introducing temporary variables works around the bug. */
5049
5050 case wordbound:
5051 DEBUG_PRINT1 ("EXECUTING wordbound.\n");
5052 if (AT_WORD_BOUNDARY (d))
5053 break;
5054 goto fail;
5055
5056 case notwordbound:
5057 DEBUG_PRINT1 ("EXECUTING notwordbound.\n");
5058 if (AT_WORD_BOUNDARY (d))
5059 goto fail;
5060 break;
5061 #else
5062 case wordbound:
5063 {
5064 boolean prevchar, thischar;
5065
5066 DEBUG_PRINT1 ("EXECUTING wordbound.\n");
5067 if (AT_STRINGS_BEG (d) || AT_STRINGS_END (d))
5068 break;
5069
5070 prevchar = WORDCHAR_P (d - 1);
5071 thischar = WORDCHAR_P (d);
5072 if (prevchar != thischar)
5073 break;
5074 goto fail;
5075 }
5076
5077 case notwordbound:
5078 {
5079 boolean prevchar, thischar;
5080
5081 DEBUG_PRINT1 ("EXECUTING notwordbound.\n");
5082 if (AT_STRINGS_BEG (d) || AT_STRINGS_END (d))
5083 goto fail;
5084
5085 prevchar = WORDCHAR_P (d - 1);
5086 thischar = WORDCHAR_P (d);
5087 if (prevchar != thischar)
5088 goto fail;
5089 break;
5090 }
5091 #endif
5092
5093 case wordbeg:
5094 DEBUG_PRINT1 ("EXECUTING wordbeg.\n");
5095 if (WORDCHAR_P (d) && (AT_STRINGS_BEG (d) || !WORDCHAR_P (d - 1)))
5096 break;
5097 goto fail;
5098
5099 case wordend:
5100 DEBUG_PRINT1 ("EXECUTING wordend.\n");
5101 if (!AT_STRINGS_BEG (d) && WORDCHAR_P (d - 1)
5102 && (!WORDCHAR_P (d) || AT_STRINGS_END (d)))
5103 break;
5104 goto fail;
5105
5106 #ifdef emacs
5107 case before_dot:
5108 DEBUG_PRINT1 ("EXECUTING before_dot.\n");
5109 if (PTR_CHAR_POS ((unsigned char *) d) >= point)
5110 goto fail;
5111 break;
5112
5113 case at_dot:
5114 DEBUG_PRINT1 ("EXECUTING at_dot.\n");
5115 if (PTR_CHAR_POS ((unsigned char *) d) != point)
5116 goto fail;
5117 break;
5118
5119 case after_dot:
5120 DEBUG_PRINT1 ("EXECUTING after_dot.\n");
5121 if (PTR_CHAR_POS ((unsigned char *) d) <= point)
5122 goto fail;
5123 break;
5124
5125 case syntaxspec:
5126 DEBUG_PRINT2 ("EXECUTING syntaxspec %d.\n", mcnt);
5127 mcnt = *p++;
5128 goto matchsyntax;
5129
5130 case wordchar:
5131 DEBUG_PRINT1 ("EXECUTING Emacs wordchar.\n");
5132 mcnt = (int) Sword;
5133 matchsyntax:
5134 PREFETCH ();
5135 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
5136 d++;
5137 if (SYNTAX (d[-1]) != (enum syntaxcode) mcnt)
5138 goto fail;
5139 SET_REGS_MATCHED ();
5140 break;
5141
5142 case notsyntaxspec:
5143 DEBUG_PRINT2 ("EXECUTING notsyntaxspec %d.\n", mcnt);
5144 mcnt = *p++;
5145 goto matchnotsyntax;
5146
5147 case notwordchar:
5148 DEBUG_PRINT1 ("EXECUTING Emacs notwordchar.\n");
5149 mcnt = (int) Sword;
5150 matchnotsyntax:
5151 PREFETCH ();
5152 /* Can't use *d++ here; SYNTAX may be an unsafe macro. */
5153 d++;
5154 if (SYNTAX (d[-1]) == (enum syntaxcode) mcnt)
5155 goto fail;
5156 SET_REGS_MATCHED ();
5157 break;
5158
5159 #else /* not emacs */
5160 case wordchar:
5161 DEBUG_PRINT1 ("EXECUTING non-Emacs wordchar.\n");
5162 PREFETCH ();
5163 if (!WORDCHAR_P (d))
5164 goto fail;
5165 SET_REGS_MATCHED ();
5166 d++;
5167 break;
5168
5169 case notwordchar:
5170 DEBUG_PRINT1 ("EXECUTING non-Emacs notwordchar.\n");
5171 PREFETCH ();
5172 if (WORDCHAR_P (d))
5173 goto fail;
5174 SET_REGS_MATCHED ();
5175 d++;
5176 break;
5177 #endif /* not emacs */
5178
5179 default:
5180 abort ();
5181 }
5182 continue; /* Successfully executed one pattern command; keep going. */
5183
5184
5185 /* We goto here if a matching operation fails. */
5186 fail:
5187 if (!FAIL_STACK_EMPTY ())
5188 { /* A restart point is known. Restore to that state. */
5189 DEBUG_PRINT1 ("\nFAIL:\n");
5190 POP_FAILURE_POINT (d, p,
5191 lowest_active_reg, highest_active_reg,
5192 regstart, regend, reg_info);
5193
5194 /* If this failure point is a dummy, try the next one. */
5195 if (!p)
5196 goto fail;
5197
5198 /* If we failed to the end of the pattern, don't examine *p. */
5199 assert (p <= pend);
5200 if (p < pend)
5201 {
5202 boolean is_a_jump_n = false;
5203
5204 /* If failed to a backwards jump that's part of a repetition
5205 loop, need to pop this failure point and use the next one. */
5206 switch ((re_opcode_t) *p)
5207 {
5208 case jump_n:
5209 is_a_jump_n = true;
5210 case maybe_pop_jump:
5211 case pop_failure_jump:
5212 case jump:
5213 p1 = p + 1;
5214 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5215 p1 += mcnt;
5216
5217 if ((is_a_jump_n && (re_opcode_t) *p1 == succeed_n)
5218 || (!is_a_jump_n
5219 && (re_opcode_t) *p1 == on_failure_jump))
5220 goto fail;
5221 break;
5222 default:
5223 /* do nothing */ ;
5224 }
5225 }
5226
5227 if (d >= string1 && d <= end1)
5228 dend = end_match_1;
5229 }
5230 else
5231 break; /* Matching at this starting point really fails. */
5232 } /* for (;;) */
5233
5234 if (best_regs_set)
5235 goto restore_best_regs;
5236
5237 FREE_VARIABLES ();
5238
5239 return -1; /* Failure to match. */
5240 } /* re_match_2 */
5241
5242 /* Subroutine definitions for re_match_2. */
5243
5244
5245 /* We are passed P pointing to a register number after a start_memory.
5246
5247 Return true if the pattern up to the corresponding stop_memory can
5248 match the empty string, and false otherwise.
5249
5250 If we find the matching stop_memory, sets P to point to one past its number.
5251 Otherwise, sets P to an undefined byte less than or equal to END.
5252
5253 We don't handle duplicates properly (yet). */
5254
5255 static boolean
5256 group_match_null_string_p (p, end, reg_info)
5257 unsigned char **p, *end;
5258 register_info_type *reg_info;
5259 {
5260 int mcnt;
5261 /* Point to after the args to the start_memory. */
5262 unsigned char *p1 = *p + 2;
5263
5264 while (p1 < end)
5265 {
5266 /* Skip over opcodes that can match nothing, and return true or
5267 false, as appropriate, when we get to one that can't, or to the
5268 matching stop_memory. */
5269
5270 switch ((re_opcode_t) *p1)
5271 {
5272 /* Could be either a loop or a series of alternatives. */
5273 case on_failure_jump:
5274 p1++;
5275 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5276
5277 /* If the next operation is not a jump backwards in the
5278 pattern. */
5279
5280 if (mcnt >= 0)
5281 {
5282 /* Go through the on_failure_jumps of the alternatives,
5283 seeing if any of the alternatives cannot match nothing.
5284 The last alternative starts with only a jump,
5285 whereas the rest start with on_failure_jump and end
5286 with a jump, e.g., here is the pattern for `a|b|c':
5287
5288 /on_failure_jump/0/6/exactn/1/a/jump_past_alt/0/6
5289 /on_failure_jump/0/6/exactn/1/b/jump_past_alt/0/3
5290 /exactn/1/c
5291
5292 So, we have to first go through the first (n-1)
5293 alternatives and then deal with the last one separately. */
5294
5295
5296 /* Deal with the first (n-1) alternatives, which start
5297 with an on_failure_jump (see above) that jumps to right
5298 past a jump_past_alt. */
5299
5300 while ((re_opcode_t) p1[mcnt-3] == jump_past_alt)
5301 {
5302 /* `mcnt' holds how many bytes long the alternative
5303 is, including the ending `jump_past_alt' and
5304 its number. */
5305
5306 if (!alt_match_null_string_p (p1, p1 + mcnt - 3,
5307 reg_info))
5308 return false;
5309
5310 /* Move to right after this alternative, including the
5311 jump_past_alt. */
5312 p1 += mcnt;
5313
5314 /* Break if it's the beginning of an n-th alternative
5315 that doesn't begin with an on_failure_jump. */
5316 if ((re_opcode_t) *p1 != on_failure_jump)
5317 break;
5318
5319 /* Still have to check that it's not an n-th
5320 alternative that starts with an on_failure_jump. */
5321 p1++;
5322 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5323 if ((re_opcode_t) p1[mcnt-3] != jump_past_alt)
5324 {
5325 /* Get to the beginning of the n-th alternative. */
5326 p1 -= 3;
5327 break;
5328 }
5329 }
5330
5331 /* Deal with the last alternative: go back and get number
5332 of the `jump_past_alt' just before it. `mcnt' contains
5333 the length of the alternative. */
5334 EXTRACT_NUMBER (mcnt, p1 - 2);
5335
5336 if (!alt_match_null_string_p (p1, p1 + mcnt, reg_info))
5337 return false;
5338
5339 p1 += mcnt; /* Get past the n-th alternative. */
5340 } /* if mcnt > 0 */
5341 break;
5342
5343
5344 case stop_memory:
5345 assert (p1[1] == **p);
5346 *p = p1 + 2;
5347 return true;
5348
5349
5350 default:
5351 if (!common_op_match_null_string_p (&p1, end, reg_info))
5352 return false;
5353 }
5354 } /* while p1 < end */
5355
5356 return false;
5357 } /* group_match_null_string_p */
5358
5359
5360 /* Similar to group_match_null_string_p, but doesn't deal with alternatives:
5361 It expects P to be the first byte of a single alternative and END one
5362 byte past the last. The alternative can contain groups. */
5363
5364 static boolean
5365 alt_match_null_string_p (p, end, reg_info)
5366 unsigned char *p, *end;
5367 register_info_type *reg_info;
5368 {
5369 int mcnt;
5370 unsigned char *p1 = p;
5371
5372 while (p1 < end)
5373 {
5374 /* Skip over opcodes that can match nothing, and break when we get
5375 to one that can't. */
5376
5377 switch ((re_opcode_t) *p1)
5378 {
5379 /* It's a loop. */
5380 case on_failure_jump:
5381 p1++;
5382 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5383 p1 += mcnt;
5384 break;
5385
5386 default:
5387 if (!common_op_match_null_string_p (&p1, end, reg_info))
5388 return false;
5389 }
5390 } /* while p1 < end */
5391
5392 return true;
5393 } /* alt_match_null_string_p */
5394
5395
5396 /* Deals with the ops common to group_match_null_string_p and
5397 alt_match_null_string_p.
5398
5399 Sets P to one after the op and its arguments, if any. */
5400
5401 static boolean
5402 common_op_match_null_string_p (p, end, reg_info)
5403 unsigned char **p, *end;
5404 register_info_type *reg_info;
5405 {
5406 int mcnt;
5407 boolean ret;
5408 int reg_no;
5409 unsigned char *p1 = *p;
5410
5411 switch ((re_opcode_t) *p1++)
5412 {
5413 case no_op:
5414 case begline:
5415 case endline:
5416 case begbuf:
5417 case endbuf:
5418 case wordbeg:
5419 case wordend:
5420 case wordbound:
5421 case notwordbound:
5422 #ifdef emacs
5423 case before_dot:
5424 case at_dot:
5425 case after_dot:
5426 #endif
5427 break;
5428
5429 case start_memory:
5430 reg_no = *p1;
5431 assert (reg_no > 0 && reg_no <= MAX_REGNUM);
5432 ret = group_match_null_string_p (&p1, end, reg_info);
5433
5434 /* Have to set this here in case we're checking a group which
5435 contains a group and a back reference to it. */
5436
5437 if (REG_MATCH_NULL_STRING_P (reg_info[reg_no]) == MATCH_NULL_UNSET_VALUE)
5438 REG_MATCH_NULL_STRING_P (reg_info[reg_no]) = ret;
5439
5440 if (!ret)
5441 return false;
5442 break;
5443
5444 /* If this is an optimized succeed_n for zero times, make the jump. */
5445 case jump:
5446 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5447 if (mcnt >= 0)
5448 p1 += mcnt;
5449 else
5450 return false;
5451 break;
5452
5453 case succeed_n:
5454 /* Get to the number of times to succeed. */
5455 p1 += 2;
5456 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5457
5458 if (mcnt == 0)
5459 {
5460 p1 -= 4;
5461 EXTRACT_NUMBER_AND_INCR (mcnt, p1);
5462 p1 += mcnt;
5463 }
5464 else
5465 return false;
5466 break;
5467
5468 case duplicate:
5469 if (!REG_MATCH_NULL_STRING_P (reg_info[*p1]))
5470 return false;
5471 break;
5472
5473 case set_number_at:
5474 p1 += 4;
5475
5476 default:
5477 /* All other opcodes mean we cannot match the empty string. */
5478 return false;
5479 }
5480
5481 *p = p1;
5482 return true;
5483 } /* common_op_match_null_string_p */
5484
5485
5486 /* Return zero if TRANSLATE[S1] and TRANSLATE[S2] are identical for LEN
5487 bytes; nonzero otherwise. */
5488
5489 static int
5490 bcmp_translate (s1, s2, len, translate)
5491 const char *s1, *s2;
5492 register int len;
5493 RE_TRANSLATE_TYPE translate;
5494 {
5495 register const unsigned char *p1 = (const unsigned char *) s1;
5496 register const unsigned char *p2 = (const unsigned char *) s2;
5497 while (len)
5498 {
5499 if (translate[*p1++] != translate[*p2++]) return 1;
5500 len--;
5501 }
5502 return 0;
5503 }
5504
5505 /* Entry points for GNU code. */
5506
5507 /* re_compile_pattern is the GNU regular expression compiler: it
5508 compiles PATTERN (of length SIZE) and puts the result in BUFP.
5509 Returns 0 if the pattern was valid, otherwise an error string.
5510
5511 Assumes the `allocated' (and perhaps `buffer') and `translate' fields
5512 are set in BUFP on entry.
5513
5514 We call regex_compile to do the actual compilation. */
5515
5516 const char *
5517 re_compile_pattern (pattern, length, bufp)
5518 const char *pattern;
5519 size_t length;
5520 struct re_pattern_buffer *bufp;
5521 {
5522 reg_errcode_t ret;
5523
5524 /* GNU code is written to assume at least RE_NREGS registers will be set
5525 (and at least one extra will be -1). */
5526 bufp->regs_allocated = REGS_UNALLOCATED;
5527
5528 /* And GNU code determines whether or not to get register information
5529 by passing null for the REGS argument to re_match, etc., not by
5530 setting no_sub. */
5531 bufp->no_sub = 0;
5532
5533 /* Match anchors at newline. */
5534 bufp->newline_anchor = 1;
5535
5536 ret = regex_compile (pattern, length, re_syntax_options, bufp);
5537
5538 if (!ret)
5539 return NULL;
5540 return gettext (re_error_msgid + re_error_msgid_idx[(int) ret]);
5541 }
5542 #ifdef _LIBC
5543 weak_alias (__re_compile_pattern, re_compile_pattern)
5544 #endif
5545
5546 /* Entry points compatible with 4.2 BSD regex library. We don't define
5547 them unless specifically requested. */
5548
5549 #if defined _REGEX_RE_COMP || defined _LIBC
5550
5551 /* BSD has one and only one pattern buffer. */
5552 static struct re_pattern_buffer re_comp_buf;
5553
5554 char *
5555 #ifdef _LIBC
5556 /* Make these definitions weak in libc, so POSIX programs can redefine
5557 these names if they don't use our functions, and still use
5558 regcomp/regexec below without link errors. */
5559 weak_function
5560 #endif
5561 re_comp (s)
5562 const char *s;
5563 {
5564 reg_errcode_t ret;
5565
5566 if (!s)
5567 {
5568 if (!re_comp_buf.buffer)
5569 return gettext ("No previous regular expression");
5570 return 0;
5571 }
5572
5573 if (!re_comp_buf.buffer)
5574 {
5575 re_comp_buf.buffer = (unsigned char *) malloc (200);
5576 if (re_comp_buf.buffer == NULL)
5577 return (char *) gettext (re_error_msgid
5578 + re_error_msgid_idx[(int) REG_ESPACE]);
5579 re_comp_buf.allocated = 200;
5580
5581 re_comp_buf.fastmap = (char *) malloc (1 << BYTEWIDTH);
5582 if (re_comp_buf.fastmap == NULL)
5583 return (char *) gettext (re_error_msgid
5584 + re_error_msgid_idx[(int) REG_ESPACE]);
5585 }
5586
5587 /* Since `re_exec' always passes NULL for the `regs' argument, we
5588 don't need to initialize the pattern buffer fields which affect it. */
5589
5590 /* Match anchors at newlines. */
5591 re_comp_buf.newline_anchor = 1;
5592
5593 ret = regex_compile (s, strlen (s), re_syntax_options, &re_comp_buf);
5594
5595 if (!ret)
5596 return NULL;
5597
5598 /* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
5599 return (char *) gettext (re_error_msgid + re_error_msgid_idx[(int) ret]);
5600 }
5601
5602
5603 int
5604 #ifdef _LIBC
5605 weak_function
5606 #endif
5607 re_exec (s)
5608 const char *s;
5609 {
5610 const int len = strlen (s);
5611 return
5612 0 <= re_search (&re_comp_buf, s, len, 0, len, (struct re_registers *) 0);
5613 }
5614
5615 #endif /* _REGEX_RE_COMP */
5616
5617 /* POSIX.2 functions. Don't define these for Emacs. */
5618
5619 #ifndef emacs
5620
5621 /* regcomp takes a regular expression as a string and compiles it.
5622
5623 PREG is a regex_t *. We do not expect any fields to be initialized,
5624 since POSIX says we shouldn't. Thus, we set
5625
5626 `buffer' to the compiled pattern;
5627 `used' to the length of the compiled pattern;
5628 `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
5629 REG_EXTENDED bit in CFLAGS is set; otherwise, to
5630 RE_SYNTAX_POSIX_BASIC;
5631 `newline_anchor' to REG_NEWLINE being set in CFLAGS;
5632 `fastmap' to an allocated space for the fastmap;
5633 `fastmap_accurate' to zero;
5634 `re_nsub' to the number of subexpressions in PATTERN.
5635
5636 PATTERN is the address of the pattern string.
5637
5638 CFLAGS is a series of bits which affect compilation.
5639
5640 If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
5641 use POSIX basic syntax.
5642
5643 If REG_NEWLINE is set, then . and [^...] don't match newline.
5644 Also, regexec will try a match beginning after every newline.
5645
5646 If REG_ICASE is set, then we considers upper- and lowercase
5647 versions of letters to be equivalent when matching.
5648
5649 If REG_NOSUB is set, then when PREG is passed to regexec, that
5650 routine will report only success or failure, and nothing about the
5651 registers.
5652
5653 It returns 0 if it succeeds, nonzero if it doesn't. (See regex.h for
5654 the return codes and their meanings.) */
5655
5656 int
5657 regcomp (preg, pattern, cflags)
5658 regex_t *preg;
5659 const char *pattern;
5660 int cflags;
5661 {
5662 reg_errcode_t ret;
5663 reg_syntax_t syntax
5664 = (cflags & REG_EXTENDED) ?
5665 RE_SYNTAX_POSIX_EXTENDED : RE_SYNTAX_POSIX_BASIC;
5666
5667 /* regex_compile will allocate the space for the compiled pattern. */
5668 preg->buffer = 0;
5669 preg->allocated = 0;
5670 preg->used = 0;
5671
5672 /* Try to allocate space for the fastmap. */
5673 preg->fastmap = (char *) malloc (1 << BYTEWIDTH);
5674
5675 if (cflags & REG_ICASE)
5676 {
5677 unsigned i;
5678
5679 preg->translate
5680 = (RE_TRANSLATE_TYPE) malloc (CHAR_SET_SIZE
5681 * sizeof (*(RE_TRANSLATE_TYPE)0));
5682 if (preg->translate == NULL)
5683 return (int) REG_ESPACE;
5684
5685 /* Map uppercase characters to corresponding lowercase ones. */
5686 for (i = 0; i < CHAR_SET_SIZE; i++)
5687 preg->translate[i] = ISUPPER (i) ? TOLOWER (i) : i;
5688 }
5689 else
5690 preg->translate = NULL;
5691
5692 /* If REG_NEWLINE is set, newlines are treated differently. */
5693 if (cflags & REG_NEWLINE)
5694 { /* REG_NEWLINE implies neither . nor [^...] match newline. */
5695 syntax &= ~RE_DOT_NEWLINE;
5696 syntax |= RE_HAT_LISTS_NOT_NEWLINE;
5697 /* It also changes the matching behavior. */
5698 preg->newline_anchor = 1;
5699 }
5700 else
5701 preg->newline_anchor = 0;
5702
5703 preg->no_sub = !!(cflags & REG_NOSUB);
5704
5705 /* POSIX says a null character in the pattern terminates it, so we
5706 can use strlen here in compiling the pattern. */
5707 ret = regex_compile (pattern, strlen (pattern), syntax, preg);
5708
5709 /* POSIX doesn't distinguish between an unmatched open-group and an
5710 unmatched close-group: both are REG_EPAREN. */
5711 if (ret == REG_ERPAREN) ret = REG_EPAREN;
5712
5713 if (ret == REG_NOERROR && preg->fastmap)
5714 {
5715 /* Compute the fastmap now, since regexec cannot modify the pattern
5716 buffer. */
5717 if (re_compile_fastmap (preg) == -2)
5718 {
5719 /* Some error occurred while computing the fastmap, just forget
5720 about it. */
5721 free (preg->fastmap);
5722 preg->fastmap = NULL;
5723 }
5724 }
5725
5726 return (int) ret;
5727 }
5728 #ifdef _LIBC
5729 weak_alias (__regcomp, regcomp)
5730 #endif
5731
5732
5733 /* regexec searches for a given pattern, specified by PREG, in the
5734 string STRING.
5735
5736 If NMATCH is zero or REG_NOSUB was set in the cflags argument to
5737 `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
5738 least NMATCH elements, and we set them to the offsets of the
5739 corresponding matched substrings.
5740
5741 EFLAGS specifies `execution flags' which affect matching: if
5742 REG_NOTBOL is set, then ^ does not match at the beginning of the
5743 string; if REG_NOTEOL is set, then $ does not match at the end.
5744
5745 We return 0 if we find a match and REG_NOMATCH if not. */
5746
5747 int
5748 regexec (preg, string, nmatch, pmatch, eflags)
5749 const regex_t *preg;
5750 const char *string;
5751 size_t nmatch;
5752 regmatch_t pmatch[];
5753 int eflags;
5754 {
5755 int ret;
5756 struct re_registers regs;
5757 regex_t private_preg;
5758 int len = strlen (string);
5759 boolean want_reg_info = !preg->no_sub && nmatch > 0;
5760
5761 private_preg = *preg;
5762
5763 private_preg.not_bol = !!(eflags & REG_NOTBOL);
5764 private_preg.not_eol = !!(eflags & REG_NOTEOL);
5765
5766 /* The user has told us exactly how many registers to return
5767 information about, via `nmatch'. We have to pass that on to the
5768 matching routines. */
5769 private_preg.regs_allocated = REGS_FIXED;
5770
5771 if (want_reg_info)
5772 {
5773 regs.num_regs = nmatch;
5774 regs.start = TALLOC (nmatch * 2, regoff_t);
5775 if (regs.start == NULL)
5776 return (int) REG_NOMATCH;
5777 regs.end = regs.start + nmatch;
5778 }
5779
5780 /* Perform the searching operation. */
5781 ret = re_search (&private_preg, string, len,
5782 /* start: */ 0, /* range: */ len,
5783 want_reg_info ? ®s : (struct re_registers *) 0);
5784
5785 /* Copy the register information to the POSIX structure. */
5786 if (want_reg_info)
5787 {
5788 if (ret >= 0)
5789 {
5790 unsigned r;
5791
5792 for (r = 0; r < nmatch; r++)
5793 {
5794 pmatch[r].rm_so = regs.start[r];
5795 pmatch[r].rm_eo = regs.end[r];
5796 }
5797 }
5798
5799 /* If we needed the temporary register info, free the space now. */
5800 free (regs.start);
5801 }
5802
5803 /* We want zero return to mean success, unlike `re_search'. */
5804 return ret >= 0 ? (int) REG_NOERROR : (int) REG_NOMATCH;
5805 }
5806 #ifdef _LIBC
5807 weak_alias (__regexec, regexec)
5808 #endif
5809
5810
5811 /* Returns a message corresponding to an error code, ERRCODE, returned
5812 from either regcomp or regexec. We don't use PREG here. */
5813
5814 size_t
5815 regerror (errcode, preg, errbuf, errbuf_size)
5816 int errcode;
5817 const regex_t *preg;
5818 char *errbuf;
5819 size_t errbuf_size;
5820 {
5821 const char *msg;
5822 size_t msg_size;
5823
5824 if (errcode < 0
5825 || errcode >= (int) (sizeof (re_error_msgid_idx)
5826 / sizeof (re_error_msgid_idx[0])))
5827 /* Only error codes returned by the rest of the code should be passed
5828 to this routine. If we are given anything else, or if other regex
5829 code generates an invalid error code, then the program has a bug.
5830 Dump core so we can fix it. */
5831 abort ();
5832
5833 msg = gettext (re_error_msgid + re_error_msgid_idx[errcode]);
5834
5835 msg_size = strlen (msg) + 1; /* Includes the null. */
5836
5837 if (errbuf_size != 0)
5838 {
5839 if (msg_size > errbuf_size)
5840 {
5841 #if defined HAVE_MEMPCPY || defined _LIBC
5842 *((char *) __mempcpy (errbuf, msg, errbuf_size - 1)) = '\0';
5843 #else
5844 memcpy (errbuf, msg, errbuf_size - 1);
5845 errbuf[errbuf_size - 1] = 0;
5846 #endif
5847 }
5848 else
5849 memcpy (errbuf, msg, msg_size);
5850 }
5851
5852 return msg_size;
5853 }
5854 #ifdef _LIBC
5855 weak_alias (__regerror, regerror)
5856 #endif
5857
5858
5859 /* Free dynamically allocated space used by PREG. */
5860
5861 void
5862 regfree (preg)
5863 regex_t *preg;
5864 {
5865 if (preg->buffer != NULL)
5866 free (preg->buffer);
5867 preg->buffer = NULL;
5868
5869 preg->allocated = 0;
5870 preg->used = 0;
5871
5872 if (preg->fastmap != NULL)
5873 free (preg->fastmap);
5874 preg->fastmap = NULL;
5875 preg->fastmap_accurate = 0;
5876
5877 if (preg->translate != NULL)
5878 free (preg->translate);
5879 preg->translate = NULL;
5880 }
5881 #ifdef _LIBC
5882 weak_alias (__regfree, regfree)
5883 #endif
5884
5885 #endif /* not emacs */
/* ![[top]](../icons/top.png)
![[bottom]](../icons/n_bottom.png)
*/