1 /* Definitions for data structures and routines for the regular
2 expression library.
3 Copyright (C) 1985,1989-93,1995-98,2000,2001,2002,2003,2005,2006
4 Free Software Foundation, Inc.
5 This file is part of the GNU C Library.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
11
12 This program 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
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License along
18 with this program; if not, write to the Free Software Foundation,
19 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
20
21 #ifndef _REGEX_H
22 #define _REGEX_H 1
23
24 #include <sys/types.h>
25
26 /* Allow the use in C++ code. */
27 #ifdef __cplusplus
28 extern "C" {
29 #endif
30
31 /* Define __USE_GNU_REGEX to declare GNU extensions that violate the
32 POSIX name space rules. */
33 #undef __USE_GNU_REGEX
34 #if (defined _GNU_SOURCE \
35 || (!defined _POSIX_C_SOURCE && !defined _POSIX_SOURCE \
36 && !defined _XOPEN_SOURCE))
37 # define __USE_GNU_REGEX 1
38 #endif
39
40 #ifdef _REGEX_LARGE_OFFSETS
41
42 /* Use types and values that are wide enough to represent signed and
43 unsigned byte offsets in memory. This currently works only when
44 the regex code is used outside of the GNU C library; it is not yet
45 supported within glibc itself, and glibc users should not define
46 _REGEX_LARGE_OFFSETS. */
47
48 /* The type of the offset of a byte within a string.
49 For historical reasons POSIX 1003.1-2004 requires that regoff_t be
50 at least as wide as off_t. However, many common POSIX platforms set
51 regoff_t to the more-sensible ssize_t and the Open Group has
52 signalled its intention to change the requirement to be that
53 regoff_t be at least as wide as ptrdiff_t and ssize_t; see XBD ERN
54 60 (2005-08-25). We don't know of any hosts where ssize_t or
55 ptrdiff_t is wider than ssize_t, so ssize_t is safe. */
56 typedef ssize_t regoff_t;
57
58 /* The type of nonnegative object indexes. Traditionally, GNU regex
59 uses 'int' for these. Code that uses __re_idx_t should work
60 regardless of whether the type is signed. */
61 typedef size_t __re_idx_t;
62
63 /* The type of object sizes. */
64 typedef size_t __re_size_t;
65
66 /* The type of object sizes, in places where the traditional code
67 uses unsigned long int. */
68 typedef size_t __re_long_size_t;
69
70 #else
71
72 /* Use types that are binary-compatible with the traditional GNU regex
73 implementation, which mishandles strings longer than INT_MAX. */
74
75 typedef int regoff_t;
76 typedef int __re_idx_t;
77 typedef unsigned int __re_size_t;
78 typedef unsigned long int __re_long_size_t;
79
80 #endif
81
82 /* The following two types have to be signed and unsigned integer type
83 wide enough to hold a value of a pointer. For most ANSI compilers
84 ptrdiff_t and size_t should be likely OK. Still size of these two
85 types is 2 for Microsoft C. Ugh... */
86 typedef long int s_reg_t;
87 typedef unsigned long int active_reg_t;
88
89 /* The following bits are used to determine the regexp syntax we
90 recognize. The set/not-set meanings are chosen so that Emacs syntax
91 remains the value 0. The bits are given in alphabetical order, and
92 the definitions shifted by one from the previous bit; thus, when we
93 add or remove a bit, only one other definition need change. */
94 typedef unsigned long int reg_syntax_t;
95
96 #ifdef __USE_GNU_REGEX
97
98 /* If this bit is not set, then \ inside a bracket expression is literal.
99 If set, then such a \ quotes the following character. */
100 # define RE_BACKSLASH_ESCAPE_IN_LISTS ((unsigned long int) 1)
101
102 /* If this bit is not set, then + and ? are operators, and \+ and \? are
103 literals.
104 If set, then \+ and \? are operators and + and ? are literals. */
105 # define RE_BK_PLUS_QM (RE_BACKSLASH_ESCAPE_IN_LISTS << 1)
106
107 /* If this bit is set, then character classes are supported. They are:
108 [:alpha:], [:upper:], [:lower:], [:digit:], [:alnum:], [:xdigit:],
109 [:space:], [:print:], [:punct:], [:graph:], and [:cntrl:].
110 If not set, then character classes are not supported. */
111 # define RE_CHAR_CLASSES (RE_BK_PLUS_QM << 1)
112
113 /* If this bit is set, then ^ and $ are always anchors (outside bracket
114 expressions, of course).
115 If this bit is not set, then it depends:
116 ^ is an anchor if it is at the beginning of a regular
117 expression or after an open-group or an alternation operator;
118 $ is an anchor if it is at the end of a regular expression, or
119 before a close-group or an alternation operator.
120
121 This bit could be (re)combined with RE_CONTEXT_INDEP_OPS, because
122 POSIX draft 11.2 says that * etc. in leading positions is undefined.
123 We already implemented a previous draft which made those constructs
124 invalid, though, so we haven't changed the code back. */
125 # define RE_CONTEXT_INDEP_ANCHORS (RE_CHAR_CLASSES << 1)
126
127 /* If this bit is set, then special characters are always special
128 regardless of where they are in the pattern.
129 If this bit is not set, then special characters are special only in
130 some contexts; otherwise they are ordinary. Specifically,
131 * + ? and intervals are only special when not after the beginning,
132 open-group, or alternation operator. */
133 # define RE_CONTEXT_INDEP_OPS (RE_CONTEXT_INDEP_ANCHORS << 1)
134
135 /* If this bit is set, then *, +, ?, and { cannot be first in an re or
136 immediately after an alternation or begin-group operator. */
137 # define RE_CONTEXT_INVALID_OPS (RE_CONTEXT_INDEP_OPS << 1)
138
139 /* If this bit is set, then . matches newline.
140 If not set, then it doesn't. */
141 # define RE_DOT_NEWLINE (RE_CONTEXT_INVALID_OPS << 1)
142
143 /* If this bit is set, then . doesn't match NUL.
144 If not set, then it does. */
145 # define RE_DOT_NOT_NULL (RE_DOT_NEWLINE << 1)
146
147 /* If this bit is set, nonmatching lists [^...] do not match newline.
148 If not set, they do. */
149 # define RE_HAT_LISTS_NOT_NEWLINE (RE_DOT_NOT_NULL << 1)
150
151 /* If this bit is set, either \{...\} or {...} defines an
152 interval, depending on RE_NO_BK_BRACES.
153 If not set, \{, \}, {, and } are literals. */
154 # define RE_INTERVALS (RE_HAT_LISTS_NOT_NEWLINE << 1)
155
156 /* If this bit is set, +, ? and | aren't recognized as operators.
157 If not set, they are. */
158 # define RE_LIMITED_OPS (RE_INTERVALS << 1)
159
160 /* If this bit is set, newline is an alternation operator.
161 If not set, newline is literal. */
162 # define RE_NEWLINE_ALT (RE_LIMITED_OPS << 1)
163
164 /* If this bit is set, then `{...}' defines an interval, and \{ and \}
165 are literals.
166 If not set, then `\{...\}' defines an interval. */
167 # define RE_NO_BK_BRACES (RE_NEWLINE_ALT << 1)
168
169 /* If this bit is set, (...) defines a group, and \( and \) are literals.
170 If not set, \(...\) defines a group, and ( and ) are literals. */
171 # define RE_NO_BK_PARENS (RE_NO_BK_BRACES << 1)
172
173 /* If this bit is set, then \<digit> matches <digit>.
174 If not set, then \<digit> is a back-reference. */
175 # define RE_NO_BK_REFS (RE_NO_BK_PARENS << 1)
176
177 /* If this bit is set, then | is an alternation operator, and \| is literal.
178 If not set, then \| is an alternation operator, and | is literal. */
179 # define RE_NO_BK_VBAR (RE_NO_BK_REFS << 1)
180
181 /* If this bit is set, then an ending range point collating higher
182 than the starting range point, as in [z-a], is invalid.
183 If not set, then when ending range point collates higher than the
184 starting range point, the range is ignored. */
185 # define RE_NO_EMPTY_RANGES (RE_NO_BK_VBAR << 1)
186
187 /* If this bit is set, then an unmatched ) is ordinary.
188 If not set, then an unmatched ) is invalid. */
189 # define RE_UNMATCHED_RIGHT_PAREN_ORD (RE_NO_EMPTY_RANGES << 1)
190
191 /* If this bit is set, succeed as soon as we match the whole pattern,
192 without further backtracking. */
193 # define RE_NO_POSIX_BACKTRACKING (RE_UNMATCHED_RIGHT_PAREN_ORD << 1)
194
195 /* If this bit is set, do not process the GNU regex operators.
196 If not set, then the GNU regex operators are recognized. */
197 # define RE_NO_GNU_OPS (RE_NO_POSIX_BACKTRACKING << 1)
198
199 /* If this bit is set, turn on internal regex debugging.
200 If not set, and debugging was on, turn it off.
201 This only works if regex.c is compiled -DDEBUG.
202 We define this bit always, so that all that's needed to turn on
203 debugging is to recompile regex.c; the calling code can always have
204 this bit set, and it won't affect anything in the normal case. */
205 # define RE_DEBUG (RE_NO_GNU_OPS << 1)
206
207 /* If this bit is set, a syntactically invalid interval is treated as
208 a string of ordinary characters. For example, the ERE 'a{1' is
209 treated as 'a\{1'. */
210 # define RE_INVALID_INTERVAL_ORD (RE_DEBUG << 1)
211
212 /* If this bit is set, then ignore case when matching.
213 If not set, then case is significant. */
214 # define RE_ICASE (RE_INVALID_INTERVAL_ORD << 1)
215
216 /* This bit is used internally like RE_CONTEXT_INDEP_ANCHORS but only
217 for ^, because it is difficult to scan the regex backwards to find
218 whether ^ should be special. */
219 # define RE_CARET_ANCHORS_HERE (RE_ICASE << 1)
220
221 /* If this bit is set, then \{ cannot be first in an bre or
222 immediately after an alternation or begin-group operator. */
223 # define RE_CONTEXT_INVALID_DUP (RE_CARET_ANCHORS_HERE << 1)
224
225 /* If this bit is set, then no_sub will be set to 1 during
226 re_compile_pattern. */
227 # define RE_NO_SUB (RE_CONTEXT_INVALID_DUP << 1)
228
229 #endif /* defined __USE_GNU_REGEX */
230
231 /* This global variable defines the particular regexp syntax to use (for
232 some interfaces). When a regexp is compiled, the syntax used is
233 stored in the pattern buffer, so changing this does not affect
234 already-compiled regexps. */
235 extern reg_syntax_t re_syntax_options;
236
237 #ifdef __USE_GNU_REGEX
238 /* Define combinations of the above bits for the standard possibilities.
239 (The [[[ comments delimit what gets put into the Texinfo file, so
240 don't delete them!) */
241 /* [[[begin syntaxes]]] */
242 # define RE_SYNTAX_EMACS 0
243
244 # define RE_SYNTAX_AWK \
245 (RE_BACKSLASH_ESCAPE_IN_LISTS | RE_DOT_NOT_NULL \
246 | RE_NO_BK_PARENS | RE_NO_BK_REFS \
247 | RE_NO_BK_VBAR | RE_NO_EMPTY_RANGES \
248 | RE_DOT_NEWLINE | RE_CONTEXT_INDEP_ANCHORS \
249 | RE_UNMATCHED_RIGHT_PAREN_ORD | RE_NO_GNU_OPS)
250
251 # define RE_SYNTAX_GNU_AWK \
252 ((RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS | RE_DEBUG) \
253 & ~(RE_DOT_NOT_NULL | RE_INTERVALS | RE_CONTEXT_INDEP_OPS \
254 | RE_CONTEXT_INVALID_OPS ))
255
256 # define RE_SYNTAX_POSIX_AWK \
257 (RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS \
258 | RE_INTERVALS | RE_NO_GNU_OPS)
259
260 # define RE_SYNTAX_GREP \
261 (RE_BK_PLUS_QM | RE_CHAR_CLASSES \
262 | RE_HAT_LISTS_NOT_NEWLINE | RE_INTERVALS \
263 | RE_NEWLINE_ALT)
264
265 # define RE_SYNTAX_EGREP \
266 (RE_CHAR_CLASSES | RE_CONTEXT_INDEP_ANCHORS \
267 | RE_CONTEXT_INDEP_OPS | RE_HAT_LISTS_NOT_NEWLINE \
268 | RE_NEWLINE_ALT | RE_NO_BK_PARENS \
269 | RE_NO_BK_VBAR)
270
271 # define RE_SYNTAX_POSIX_EGREP \
272 (RE_SYNTAX_EGREP | RE_INTERVALS | RE_NO_BK_BRACES \
273 | RE_INVALID_INTERVAL_ORD)
274
275 /* P1003.2/D11.2, section 4.20.7.1, lines 5078ff. */
276 # define RE_SYNTAX_ED RE_SYNTAX_POSIX_BASIC
277
278 # define RE_SYNTAX_SED RE_SYNTAX_POSIX_BASIC
279
280 /* Syntax bits common to both basic and extended POSIX regex syntax. */
281 # define _RE_SYNTAX_POSIX_COMMON \
282 (RE_CHAR_CLASSES | RE_DOT_NEWLINE | RE_DOT_NOT_NULL \
283 | RE_INTERVALS | RE_NO_EMPTY_RANGES)
284
285 # define RE_SYNTAX_POSIX_BASIC \
286 (_RE_SYNTAX_POSIX_COMMON | RE_BK_PLUS_QM | RE_CONTEXT_INVALID_DUP)
287
288 /* Differs from ..._POSIX_BASIC only in that RE_BK_PLUS_QM becomes
289 RE_LIMITED_OPS, i.e., \? \+ \| are not recognized. Actually, this
290 isn't minimal, since other operators, such as \`, aren't disabled. */
291 # define RE_SYNTAX_POSIX_MINIMAL_BASIC \
292 (_RE_SYNTAX_POSIX_COMMON | RE_LIMITED_OPS)
293
294 # define RE_SYNTAX_POSIX_EXTENDED \
295 (_RE_SYNTAX_POSIX_COMMON | RE_CONTEXT_INDEP_ANCHORS \
296 | RE_CONTEXT_INDEP_OPS | RE_NO_BK_BRACES \
297 | RE_NO_BK_PARENS | RE_NO_BK_VBAR \
298 | RE_CONTEXT_INVALID_OPS | RE_UNMATCHED_RIGHT_PAREN_ORD)
299
300 /* Differs from ..._POSIX_EXTENDED in that RE_CONTEXT_INDEP_OPS is
301 removed and RE_NO_BK_REFS is added. */
302 # define RE_SYNTAX_POSIX_MINIMAL_EXTENDED \
303 (_RE_SYNTAX_POSIX_COMMON | RE_CONTEXT_INDEP_ANCHORS \
304 | RE_CONTEXT_INVALID_OPS | RE_NO_BK_BRACES \
305 | RE_NO_BK_PARENS | RE_NO_BK_REFS \
306 | RE_NO_BK_VBAR | RE_UNMATCHED_RIGHT_PAREN_ORD)
307 /* [[[end syntaxes]]] */
308
309 #endif /* defined __USE_GNU_REGEX */
310
311 #ifdef __USE_GNU_REGEX
312
313 /* Maximum number of duplicates an interval can allow. POSIX-conforming
314 systems might define this in <limits.h>, but we want our
315 value, so remove any previous define. */
316 # ifdef RE_DUP_MAX
317 # undef RE_DUP_MAX
318 # endif
319
320 /* RE_DUP_MAX is 2**15 - 1 because an earlier implementation stored
321 the counter as a 2-byte signed integer. This is no longer true, so
322 RE_DUP_MAX could be increased to (INT_MAX / 10 - 1), or to
323 ((SIZE_MAX - 2) / 10 - 1) if _REGEX_LARGE_OFFSETS is defined.
324 However, there would be a huge performance problem if someone
325 actually used a pattern like a\{214748363\}, so RE_DUP_MAX retains
326 its historical value. */
327 # define RE_DUP_MAX (0x7fff)
328
329 #endif /* defined __USE_GNU_REGEX */
330
331
332 /* POSIX `cflags' bits (i.e., information for `regcomp'). */
333
334 /* If this bit is set, then use extended regular expression syntax.
335 If not set, then use basic regular expression syntax. */
336 #define REG_EXTENDED 1
337
338 /* If this bit is set, then ignore case when matching.
339 If not set, then case is significant. */
340 #define REG_ICASE (1 << 1)
341
342 /* If this bit is set, then anchors do not match at newline
343 characters in the string.
344 If not set, then anchors do match at newlines. */
345 #define REG_NEWLINE (1 << 2)
346
347 /* If this bit is set, then report only success or fail in regexec.
348 If not set, then returns differ between not matching and errors. */
349 #define REG_NOSUB (1 << 3)
350
351
352 /* POSIX `eflags' bits (i.e., information for regexec). */
353
354 /* If this bit is set, then the beginning-of-line operator doesn't match
355 the beginning of the string (presumably because it's not the
356 beginning of a line).
357 If not set, then the beginning-of-line operator does match the
358 beginning of the string. */
359 #define REG_NOTBOL 1
360
361 /* Like REG_NOTBOL, except for the end-of-line. */
362 #define REG_NOTEOL (1 << 1)
363
364 /* Use PMATCH[0] to delimit the start and end of the search in the
365 buffer. */
366 #define REG_STARTEND (1 << 2)
367
368
369 /* If any error codes are removed, changed, or added, update the
370 `__re_error_msgid' table in regcomp.c. */
371
372 typedef enum
373 {
374 _REG_ENOSYS = -1, /* This will never happen for this implementation. */
375 _REG_NOERROR = 0, /* Success. */
376 _REG_NOMATCH, /* Didn't find a match (for regexec). */
377
378 /* POSIX regcomp return error codes. (In the order listed in the
379 standard.) */
380 _REG_BADPAT, /* Invalid pattern. */
381 _REG_ECOLLATE, /* Invalid collating element. */
382 _REG_ECTYPE, /* Invalid character class name. */
383 _REG_EESCAPE, /* Trailing backslash. */
384 _REG_ESUBREG, /* Invalid back reference. */
385 _REG_EBRACK, /* Unmatched left bracket. */
386 _REG_EPAREN, /* Parenthesis imbalance. */
387 _REG_EBRACE, /* Unmatched \{. */
388 _REG_BADBR, /* Invalid contents of \{\}. */
389 _REG_ERANGE, /* Invalid range end. */
390 _REG_ESPACE, /* Ran out of memory. */
391 _REG_BADRPT, /* No preceding re for repetition op. */
392
393 /* Error codes we've added. */
394 _REG_EEND, /* Premature end. */
395 _REG_ESIZE, /* Compiled pattern bigger than 2^16 bytes. */
396 _REG_ERPAREN /* Unmatched ) or \); not returned from regcomp. */
397 } reg_errcode_t;
398
399 #ifdef _XOPEN_SOURCE
400 # define REG_ENOSYS _REG_ENOSYS
401 #endif
402 #define REG_NOERROR _REG_NOERROR
403 #define REG_NOMATCH _REG_NOMATCH
404 #define REG_BADPAT _REG_BADPAT
405 #define REG_ECOLLATE _REG_ECOLLATE
406 #define REG_ECTYPE _REG_ECTYPE
407 #define REG_EESCAPE _REG_EESCAPE
408 #define REG_ESUBREG _REG_ESUBREG
409 #define REG_EBRACK _REG_EBRACK
410 #define REG_EPAREN _REG_EPAREN
411 #define REG_EBRACE _REG_EBRACE
412 #define REG_BADBR _REG_BADBR
413 #define REG_ERANGE _REG_ERANGE
414 #define REG_ESPACE _REG_ESPACE
415 #define REG_BADRPT _REG_BADRPT
416 #define REG_EEND _REG_EEND
417 #define REG_ESIZE _REG_ESIZE
418 #define REG_ERPAREN _REG_ERPAREN
419
420 /* struct re_pattern_buffer normally uses member names like `buffer'
421 that POSIX does not allow. In POSIX mode these members have names
422 with leading `re_' (e.g., `re_buffer'). */
423 #ifdef __USE_GNU_REGEX
424 # define _REG_RE_NAME(id) id
425 # define _REG_RM_NAME(id) id
426 #else
427 # define _REG_RE_NAME(id) re_##id
428 # define _REG_RM_NAME(id) rm_##id
429 #endif
430
431 /* The user can specify the type of the re_translate member by
432 defining the macro RE_TRANSLATE_TYPE, which defaults to unsigned
433 char *. This pollutes the POSIX name space, so in POSIX mode just
434 use unsigned char *. */
435 #ifdef __USE_GNU_REGEX
436 # ifndef RE_TRANSLATE_TYPE
437 # define RE_TRANSLATE_TYPE unsigned char *
438 # endif
439 # define REG_TRANSLATE_TYPE RE_TRANSLATE_TYPE
440 #else
441 # define REG_TRANSLATE_TYPE unsigned char *
442 #endif
443
444 /* This data structure represents a compiled pattern. Before calling
445 the pattern compiler, the fields `buffer', `allocated', `fastmap',
446 `translate', and `no_sub' can be set. After the pattern has been
447 compiled, the `re_nsub' field is available. All other fields are
448 private to the regex routines. */
449
450 struct re_pattern_buffer
451 {
452 /* Space that holds the compiled pattern. It is declared as
453 `unsigned char *' because its elements are sometimes used as
454 array indexes. */
455 unsigned char *_REG_RE_NAME (buffer);
456
457 /* Number of bytes to which `buffer' points. */
458 __re_long_size_t _REG_RE_NAME (allocated);
459
460 /* Number of bytes actually used in `buffer'. */
461 __re_long_size_t _REG_RE_NAME (used);
462
463 /* Syntax setting with which the pattern was compiled. */
464 reg_syntax_t _REG_RE_NAME (syntax);
465
466 /* Pointer to a fastmap, if any, otherwise zero. re_search uses the
467 fastmap, if there is one, to skip over impossible starting points
468 for matches. */
469 char *_REG_RE_NAME (fastmap);
470
471 /* Either a translate table to apply to all characters before
472 comparing them, or zero for no translation. The translation is
473 applied to a pattern when it is compiled and to a string when it
474 is matched. */
475 REG_TRANSLATE_TYPE _REG_RE_NAME (translate);
476
477 /* Number of subexpressions found by the compiler. */
478 size_t re_nsub;
479
480 /* Zero if this pattern cannot match the empty string, one else.
481 Well, in truth it's used only in `re_search_2', to see whether or
482 not we should use the fastmap, so we don't set this absolutely
483 perfectly; see `re_compile_fastmap' (the `duplicate' case). */
484 unsigned int _REG_RE_NAME (can_be_null) : 1;
485
486 /* If REGS_UNALLOCATED, allocate space in the `regs' structure
487 for `max (RE_NREGS, re_nsub + 1)' groups.
488 If REGS_REALLOCATE, reallocate space if necessary.
489 If REGS_FIXED, use what's there. */
490 #ifdef __USE_GNU_REGEX
491 # define REGS_UNALLOCATED 0
492 # define REGS_REALLOCATE 1
493 # define REGS_FIXED 2
494 #endif
495 unsigned int _REG_RE_NAME (regs_allocated) : 2;
496
497 /* Set to zero when `regex_compile' compiles a pattern; set to one
498 by `re_compile_fastmap' if it updates the fastmap. */
499 unsigned int _REG_RE_NAME (fastmap_accurate) : 1;
500
501 /* If set, `re_match_2' does not return information about
502 subexpressions. */
503 unsigned int _REG_RE_NAME (no_sub) : 1;
504
505 /* If set, a beginning-of-line anchor doesn't match at the beginning
506 of the string. */
507 unsigned int _REG_RE_NAME (not_bol) : 1;
508
509 /* Similarly for an end-of-line anchor. */
510 unsigned int _REG_RE_NAME (not_eol) : 1;
511
512 /* If true, an anchor at a newline matches. */
513 unsigned int _REG_RE_NAME (newline_anchor) : 1;
514
515 /* [[[end pattern_buffer]]] */
516 };
517
518 typedef struct re_pattern_buffer regex_t;
519
520 /* This is the structure we store register match data in. See
521 regex.texinfo for a full description of what registers match. */
522 struct re_registers
523 {
524 __re_size_t _REG_RM_NAME (num_regs);
525 regoff_t *_REG_RM_NAME (start);
526 regoff_t *_REG_RM_NAME (end);
527 };
528
529
530 /* If `regs_allocated' is REGS_UNALLOCATED in the pattern buffer,
531 `re_match_2' returns information about at least this many registers
532 the first time a `regs' structure is passed. */
533 #if !defined RE_NREGS && defined __USE_GNU_REGEX
534 # define RE_NREGS 30
535 #endif
536
537
538 /* POSIX specification for registers. Aside from the different names than
539 `re_registers', POSIX uses an array of structures, instead of a
540 structure of arrays. */
541 typedef struct
542 {
543 regoff_t rm_so; /* Byte offset from string's start to substring's start. */
544 regoff_t rm_eo; /* Byte offset from string's start to substring's end. */
545 } regmatch_t;
546
547 /* Declarations for routines. */
548
549 /* Sets the current default syntax to SYNTAX, and return the old syntax.
550 You can also simply assign to the `re_syntax_options' variable. */
551 extern reg_syntax_t re_set_syntax (reg_syntax_t __syntax);
552
553 /* Compile the regular expression PATTERN, with length LENGTH
554 and syntax given by the global `re_syntax_options', into the buffer
555 BUFFER. Return NULL if successful, and an error string if not. */
556 extern const char *re_compile_pattern (const char *__pattern, size_t __length,
557 struct re_pattern_buffer *__buffer);
558
559
560 /* Compile a fastmap for the compiled pattern in BUFFER; used to
561 accelerate searches. Return 0 if successful and -2 if was an
562 internal error. */
563 extern int re_compile_fastmap (struct re_pattern_buffer *__buffer);
564
565
566 /* Search in the string STRING (with length LENGTH) for the pattern
567 compiled into BUFFER. Start searching at position START, for RANGE
568 characters. Return the starting position of the match, -1 for no
569 match, or -2 for an internal error. Also return register
570 information in REGS (if REGS and BUFFER->no_sub are nonzero). */
571 extern regoff_t re_search (struct re_pattern_buffer *__buffer,
572 const char *__string, __re_idx_t __length,
573 __re_idx_t __start, regoff_t __range,
574 struct re_registers *__regs);
575
576
577 /* Like `re_search', but search in the concatenation of STRING1 and
578 STRING2. Also, stop searching at index START + STOP. */
579 extern regoff_t re_search_2 (struct re_pattern_buffer *__buffer,
580 const char *__string1, __re_idx_t __length1,
581 const char *__string2, __re_idx_t __length2,
582 __re_idx_t __start, regoff_t __range,
583 struct re_registers *__regs,
584 __re_idx_t __stop);
585
586
587 /* Like `re_search', but return how many characters in STRING the regexp
588 in BUFFER matched, starting at position START. */
589 extern regoff_t re_match (struct re_pattern_buffer *__buffer,
590 const char *__string, __re_idx_t __length,
591 __re_idx_t __start, struct re_registers *__regs);
592
593
594 /* Relates to `re_match' as `re_search_2' relates to `re_search'. */
595 extern regoff_t re_match_2 (struct re_pattern_buffer *__buffer,
596 const char *__string1, __re_idx_t __length1,
597 const char *__string2, __re_idx_t __length2,
598 __re_idx_t __start, struct re_registers *__regs,
599 __re_idx_t __stop);
600
601
602 /* Set REGS to hold NUM_REGS registers, storing them in STARTS and
603 ENDS. Subsequent matches using BUFFER and REGS will use this memory
604 for recording register information. STARTS and ENDS must be
605 allocated with malloc, and must each be at least `NUM_REGS * sizeof
606 (regoff_t)' bytes long.
607
608 If NUM_REGS == 0, then subsequent matches should allocate their own
609 register data.
610
611 Unless this function is called, the first search or match using
612 PATTERN_BUFFER will allocate its own register data, without
613 freeing the old data. */
614 extern void re_set_registers (struct re_pattern_buffer *__buffer,
615 struct re_registers *__regs,
616 __re_size_t __num_regs,
617 regoff_t *__starts, regoff_t *__ends);
618
619 #if defined _REGEX_RE_COMP || defined _LIBC
620 # ifndef _CRAY
621 /* 4.2 bsd compatibility. */
622 extern char *re_comp (const char *);
623 extern int re_exec (const char *);
624 # endif
625 #endif
626
627 /* GCC 2.95 and later have "__restrict"; C99 compilers have
628 "restrict", and "configure" may have defined "restrict".
629 Other compilers use __restrict, __restrict__, and _Restrict, and
630 'configure' might #define 'restrict' to those words, so pick a
631 different name. */
632 #ifndef _Restrict_
633 # if 199901L <= __STDC_VERSION__
634 # define _Restrict_ restrict
635 # elif 2 < __GNUC__ || (2 == __GNUC__ && 95 <= __GNUC_MINOR__)
636 # define _Restrict_ __restrict
637 # else
638 # define _Restrict_
639 # endif
640 #endif
641 /* gcc 3.1 and up support the [restrict] syntax. Don't trust
642 sys/cdefs.h's definition of __restrict_arr, though, as it
643 mishandles gcc -ansi -pedantic. */
644 #ifndef _Restrict_arr_
645 # if ((199901L <= __STDC_VERSION__ \
646 || ((3 < __GNUC__ || (3 == __GNUC__ && 1 <= __GNUC_MINOR__)) \
647 && !__STRICT_ANSI__)) \
648 && !defined __GNUG__)
649 # define _Restrict_arr_ _Restrict_
650 # else
651 # define _Restrict_arr_
652 # endif
653 #endif
654
655 /* POSIX compatibility. */
656 extern int regcomp (regex_t *_Restrict_ __preg,
657 const char *_Restrict_ __pattern,
658 int __cflags);
659
660 extern int regexec (const regex_t *_Restrict_ __preg,
661 const char *_Restrict_ __string, size_t __nmatch,
662 regmatch_t __pmatch[_Restrict_arr_],
663 int __eflags);
664
665 extern size_t regerror (int __errcode, const regex_t *_Restrict_ __preg,
666 char *_Restrict_ __errbuf, size_t __errbuf_size);
667
668 extern void regfree (regex_t *__preg);
669
670
671 #ifdef __cplusplus
672 }
673 #endif /* C++ */
674
675 #endif /* regex.h */