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Tanguy Pruvot36efc942011-11-20 14:41:41 +01001/* Definitions for data structures and routines for the regular
2 expression library, version 0.12.
3
4 Copyright (C) 1985, 89, 90, 91, 92, 93, 95 Free Software Foundation, Inc.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
9 any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software Foundation,
18 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
19
20#ifndef __REGEXP_LIBRARY_H__
21#define __REGEXP_LIBRARY_H__
22
23/* POSIX says that <sys/types.h> must be included (by the caller) before
24 <regex.h>. */
25
26#if !defined (_POSIX_C_SOURCE) && !defined (_POSIX_SOURCE) && defined (VMS)
27/* VMS doesn't have `size_t' in <sys/types.h>, even though POSIX says it
28 should be there. */
29#include <stddef.h>
30#endif
31
32
33/* The following bits are used to determine the regexp syntax we
34 recognize. The set/not-set meanings are chosen so that Emacs syntax
35 remains the value 0. The bits are given in alphabetical order, and
36 the definitions shifted by one from the previous bit; thus, when we
37 add or remove a bit, only one other definition need change. */
38typedef unsigned reg_syntax_t;
39
40/* If this bit is not set, then \ inside a bracket expression is literal.
41 If set, then such a \ quotes the following character. */
42#define RE_BACKSLASH_ESCAPE_IN_LISTS (1)
43
44/* If this bit is not set, then + and ? are operators, and \+ and \? are
45 literals.
46 If set, then \+ and \? are operators and + and ? are literals. */
47#define RE_BK_PLUS_QM (RE_BACKSLASH_ESCAPE_IN_LISTS << 1)
48
49/* If this bit is set, then character classes are supported. They are:
50 [:alpha:], [:upper:], [:lower:], [:digit:], [:alnum:], [:xdigit:],
51 [:space:], [:print:], [:punct:], [:graph:], and [:cntrl:].
52 If not set, then character classes are not supported. */
53#define RE_CHAR_CLASSES (RE_BK_PLUS_QM << 1)
54
55/* If this bit is set, then ^ and $ are always anchors (outside bracket
56 expressions, of course).
57 If this bit is not set, then it depends:
58 ^ is an anchor if it is at the beginning of a regular
59 expression or after an open-group or an alternation operator;
60 $ is an anchor if it is at the end of a regular expression, or
61 before a close-group or an alternation operator.
62
63 This bit could be (re)combined with RE_CONTEXT_INDEP_OPS, because
64 POSIX draft 11.2 says that * etc. in leading positions is undefined.
65 We already implemented a previous draft which made those constructs
66 invalid, though, so we haven't changed the code back. */
67#define RE_CONTEXT_INDEP_ANCHORS (RE_CHAR_CLASSES << 1)
68
69/* If this bit is set, then special characters are always special
70 regardless of where they are in the pattern.
71 If this bit is not set, then special characters are special only in
72 some contexts; otherwise they are ordinary. Specifically,
73 * + ? and intervals are only special when not after the beginning,
74 open-group, or alternation operator. */
75#define RE_CONTEXT_INDEP_OPS (RE_CONTEXT_INDEP_ANCHORS << 1)
76
77/* If this bit is set, then *, +, ?, and { cannot be first in an re or
78 immediately after an alternation or begin-group operator. */
79#define RE_CONTEXT_INVALID_OPS (RE_CONTEXT_INDEP_OPS << 1)
80
81/* If this bit is set, then . matches newline.
82 If not set, then it doesn't. */
83#define RE_DOT_NEWLINE (RE_CONTEXT_INVALID_OPS << 1)
84
85/* If this bit is set, then . doesn't match NUL.
86 If not set, then it does. */
87#define RE_DOT_NOT_NULL (RE_DOT_NEWLINE << 1)
88
89/* If this bit is set, nonmatching lists [^...] do not match newline.
90 If not set, they do. */
91#define RE_HAT_LISTS_NOT_NEWLINE (RE_DOT_NOT_NULL << 1)
92
93/* If this bit is set, either \{...\} or {...} defines an
94 interval, depending on RE_NO_BK_BRACES.
95 If not set, \{, \}, {, and } are literals. */
96#define RE_INTERVALS (RE_HAT_LISTS_NOT_NEWLINE << 1)
97
98/* If this bit is set, +, ? and | aren't recognized as operators.
99 If not set, they are. */
100#define RE_LIMITED_OPS (RE_INTERVALS << 1)
101
102/* If this bit is set, newline is an alternation operator.
103 If not set, newline is literal. */
104#define RE_NEWLINE_ALT (RE_LIMITED_OPS << 1)
105
106/* If this bit is set, then `{...}' defines an interval, and \{ and \}
107 are literals.
108 If not set, then `\{...\}' defines an interval. */
109#define RE_NO_BK_BRACES (RE_NEWLINE_ALT << 1)
110
111/* If this bit is set, (...) defines a group, and \( and \) are literals.
112 If not set, \(...\) defines a group, and ( and ) are literals. */
113#define RE_NO_BK_PARENS (RE_NO_BK_BRACES << 1)
114
115/* If this bit is set, then \<digit> matches <digit>.
116 If not set, then \<digit> is a back-reference. */
117#define RE_NO_BK_REFS (RE_NO_BK_PARENS << 1)
118
119/* If this bit is set, then | is an alternation operator, and \| is literal.
120 If not set, then \| is an alternation operator, and | is literal. */
121#define RE_NO_BK_VBAR (RE_NO_BK_REFS << 1)
122
123/* If this bit is set, then an ending range point collating higher
124 than the starting range point, as in [z-a], is invalid.
125 If not set, then when ending range point collates higher than the
126 starting range point, the range is ignored. */
127#define RE_NO_EMPTY_RANGES (RE_NO_BK_VBAR << 1)
128
129/* If this bit is set, then an unmatched ) is ordinary.
130 If not set, then an unmatched ) is invalid. */
131#define RE_UNMATCHED_RIGHT_PAREN_ORD (RE_NO_EMPTY_RANGES << 1)
132
133/* If this bit is set, succeed as soon as we match the whole pattern,
134 without further backtracking. */
135#define RE_NO_POSIX_BACKTRACKING (RE_UNMATCHED_RIGHT_PAREN_ORD << 1)
136
maxwen27116ba2015-08-14 21:41:28 +0200137/* If this bit is set, do not process the GNU regex operators.
138 If not set, then the GNU regex operators are recognized. */
139#define RE_NO_GNU_OPS (RE_NO_POSIX_BACKTRACKING << 1)
140
141/* If this bit is set, turn on internal regex debugging.
142 If not set, and debugging was on, turn it off.
143 This only works if regex.c is compiled -DDEBUG.
144 We define this bit always, so that all that's needed to turn on
145 debugging is to recompile regex.c; the calling code can always have
146 this bit set, and it won't affect anything in the normal case. */
147#define RE_DEBUG (RE_NO_GNU_OPS << 1)
148
149/* If this bit is set, a syntactically invalid interval is treated as
150 a string of ordinary characters. For example, the ERE 'a{1' is
151 treated as 'a\{1'. */
152#define RE_INVALID_INTERVAL_ORD (RE_DEBUG << 1)
153
154/* If this bit is set, then ignore case when matching.
155 If not set, then case is significant. */
156#define RE_ICASE (RE_INVALID_INTERVAL_ORD << 1)
157
Tanguy Pruvot36efc942011-11-20 14:41:41 +0100158/* This global variable defines the particular regexp syntax to use (for
159 some interfaces). When a regexp is compiled, the syntax used is
160 stored in the pattern buffer, so changing this does not affect
161 already-compiled regexps. */
162extern reg_syntax_t re_syntax_options;
163
164/* Define combinations of the above bits for the standard possibilities.
165 (The [[[ comments delimit what gets put into the Texinfo file, so
166 don't delete them!) */
167/* [[[begin syntaxes]]] */
168#define RE_SYNTAX_EMACS 0
169
170#define RE_SYNTAX_AWK \
171 (RE_BACKSLASH_ESCAPE_IN_LISTS | RE_DOT_NOT_NULL \
172 | RE_NO_BK_PARENS | RE_NO_BK_REFS \
173 | RE_NO_BK_VBAR | RE_NO_EMPTY_RANGES \
174 | RE_UNMATCHED_RIGHT_PAREN_ORD)
175
176#define RE_SYNTAX_POSIX_AWK \
177 (RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS)
178
179#define RE_SYNTAX_GREP \
180 (RE_BK_PLUS_QM | RE_CHAR_CLASSES \
181 | RE_HAT_LISTS_NOT_NEWLINE | RE_INTERVALS \
182 | RE_NEWLINE_ALT)
183
184#define RE_SYNTAX_EGREP \
185 (RE_CHAR_CLASSES | RE_CONTEXT_INDEP_ANCHORS \
186 | RE_CONTEXT_INDEP_OPS | RE_HAT_LISTS_NOT_NEWLINE \
187 | RE_NEWLINE_ALT | RE_NO_BK_PARENS \
188 | RE_NO_BK_VBAR)
189
190#define RE_SYNTAX_POSIX_EGREP \
191 (RE_SYNTAX_EGREP | RE_INTERVALS | RE_NO_BK_BRACES)
192
193/* P1003.2/D11.2, section 4.20.7.1, lines 5078ff. */
194#define RE_SYNTAX_ED RE_SYNTAX_POSIX_BASIC
195
196#define RE_SYNTAX_SED RE_SYNTAX_POSIX_BASIC
197
198/* Syntax bits common to both basic and extended POSIX regex syntax. */
199#define _RE_SYNTAX_POSIX_COMMON \
200 (RE_CHAR_CLASSES | RE_DOT_NEWLINE | RE_DOT_NOT_NULL \
201 | RE_INTERVALS | RE_NO_EMPTY_RANGES)
202
203#define RE_SYNTAX_POSIX_BASIC \
204 (_RE_SYNTAX_POSIX_COMMON | RE_BK_PLUS_QM)
205
206/* Differs from ..._POSIX_BASIC only in that RE_BK_PLUS_QM becomes
207 RE_LIMITED_OPS, i.e., \? \+ \| are not recognized. Actually, this
208 isn't minimal, since other operators, such as \`, aren't disabled. */
209#define RE_SYNTAX_POSIX_MINIMAL_BASIC \
210 (_RE_SYNTAX_POSIX_COMMON | RE_LIMITED_OPS)
211
212#define RE_SYNTAX_POSIX_EXTENDED \
213 (_RE_SYNTAX_POSIX_COMMON | RE_CONTEXT_INDEP_ANCHORS \
214 | RE_CONTEXT_INDEP_OPS | RE_NO_BK_BRACES \
215 | RE_NO_BK_PARENS | RE_NO_BK_VBAR \
216 | RE_UNMATCHED_RIGHT_PAREN_ORD)
217
218/* Differs from ..._POSIX_EXTENDED in that RE_CONTEXT_INVALID_OPS
219 replaces RE_CONTEXT_INDEP_OPS and RE_NO_BK_REFS is added. */
220#define RE_SYNTAX_POSIX_MINIMAL_EXTENDED \
221 (_RE_SYNTAX_POSIX_COMMON | RE_CONTEXT_INDEP_ANCHORS \
222 | RE_CONTEXT_INVALID_OPS | RE_NO_BK_BRACES \
223 | RE_NO_BK_PARENS | RE_NO_BK_REFS \
224 | RE_NO_BK_VBAR | RE_UNMATCHED_RIGHT_PAREN_ORD)
225/* [[[end syntaxes]]] */
226
227/* Maximum number of duplicates an interval can allow. Some systems
228 (erroneously) define this in other header files, but we want our
229 value, so remove any previous define. */
230#ifdef RE_DUP_MAX
231#undef RE_DUP_MAX
232#endif
233#define RE_DUP_MAX ((1 << 15) - 1)
234
235
236/* POSIX `cflags' bits (i.e., information for `regcomp'). */
237
238/* If this bit is set, then use extended regular expression syntax.
239 If not set, then use basic regular expression syntax. */
240#define REG_EXTENDED 1
241
242/* If this bit is set, then ignore case when matching.
243 If not set, then case is significant. */
244#define REG_ICASE (REG_EXTENDED << 1)
245
246/* If this bit is set, then anchors do not match at newline
247 characters in the string.
248 If not set, then anchors do match at newlines. */
249#define REG_NEWLINE (REG_ICASE << 1)
250
251/* If this bit is set, then report only success or fail in regexec.
252 If not set, then returns differ between not matching and errors. */
253#define REG_NOSUB (REG_NEWLINE << 1)
254
255
256/* POSIX `eflags' bits (i.e., information for regexec). */
257
258/* If this bit is set, then the beginning-of-line operator doesn't match
259 the beginning of the string (presumably because it's not the
260 beginning of a line).
261 If not set, then the beginning-of-line operator does match the
262 beginning of the string. */
263#define REG_NOTBOL 1
264
265/* Like REG_NOTBOL, except for the end-of-line. */
266#define REG_NOTEOL (1 << 1)
267
268
269/* If any error codes are removed, changed, or added, update the
270 `re_error_msg' table in regex.c. */
271typedef enum
272{
273 REG_NOERROR = 0, /* Success. */
274 REG_NOMATCH, /* Didn't find a match (for regexec). */
275
276 /* POSIX regcomp return error codes. (In the order listed in the
277 standard.) */
278 REG_BADPAT, /* Invalid pattern. */
279 REG_ECOLLATE, /* Not implemented. */
280 REG_ECTYPE, /* Invalid character class name. */
281 REG_EESCAPE, /* Trailing backslash. */
282 REG_ESUBREG, /* Invalid back reference. */
283 REG_EBRACK, /* Unmatched left bracket. */
284 REG_EPAREN, /* Parenthesis imbalance. */
285 REG_EBRACE, /* Unmatched \{. */
286 REG_BADBR, /* Invalid contents of \{\}. */
287 REG_ERANGE, /* Invalid range end. */
288 REG_ESPACE, /* Ran out of memory. */
289 REG_BADRPT, /* No preceding re for repetition op. */
290
291 /* Error codes we've added. */
292 REG_EEND, /* Premature end. */
293 REG_ESIZE, /* Compiled pattern bigger than 2^16 bytes. */
294 REG_ERPAREN /* Unmatched ) or \); not returned from regcomp. */
295} reg_errcode_t;
296
297/* This data structure represents a compiled pattern. Before calling
298 the pattern compiler, the fields `buffer', `allocated', `fastmap',
299 `translate', and `no_sub' can be set. After the pattern has been
300 compiled, the `re_nsub' field is available. All other fields are
301 private to the regex routines. */
302
303#ifndef RE_TRANSLATE_TYPE
304#define RE_TRANSLATE_TYPE char *
305#endif
306
307struct re_pattern_buffer
308{
309/* [[[begin pattern_buffer]]] */
310 /* Space that holds the compiled pattern. It is declared as
311 `unsigned char *' because its elements are
312 sometimes used as array indexes. */
313 unsigned char *buffer;
314
315 /* Number of bytes to which `buffer' points. */
316 unsigned long allocated;
317
318 /* Number of bytes actually used in `buffer'. */
319 unsigned long used;
320
321 /* Syntax setting with which the pattern was compiled. */
322 reg_syntax_t syntax;
323
324 /* Pointer to a fastmap, if any, otherwise zero. re_search uses
325 the fastmap, if there is one, to skip over impossible
326 starting points for matches. */
327 char *fastmap;
328
329 /* Either a translate table to apply to all characters before
330 comparing them, or zero for no translation. The translation
331 is applied to a pattern when it is compiled and to a string
332 when it is matched. */
333 RE_TRANSLATE_TYPE translate;
334
335 /* Number of subexpressions found by the compiler. */
336 size_t re_nsub;
337
338 /* Zero if this pattern cannot match the empty string, one else.
339 Well, in truth it's used only in `re_search_2', to see
340 whether or not we should use the fastmap, so we don't set
341 this absolutely perfectly; see `re_compile_fastmap' (the
342 `duplicate' case). */
343 unsigned can_be_null : 1;
344
345 /* If REGS_UNALLOCATED, allocate space in the `regs' structure
346 for `max (RE_NREGS, re_nsub + 1)' groups.
347 If REGS_REALLOCATE, reallocate space if necessary.
348 If REGS_FIXED, use what's there. */
349#define REGS_UNALLOCATED 0
350#define REGS_REALLOCATE 1
351#define REGS_FIXED 2
352 unsigned regs_allocated : 2;
353
354 /* Set to zero when `regex_compile' compiles a pattern; set to one
355 by `re_compile_fastmap' if it updates the fastmap. */
356 unsigned fastmap_accurate : 1;
357
358 /* If set, `re_match_2' does not return information about
359 subexpressions. */
360 unsigned no_sub : 1;
361
362 /* If set, a beginning-of-line anchor doesn't match at the
363 beginning of the string. */
364 unsigned not_bol : 1;
365
366 /* Similarly for an end-of-line anchor. */
367 unsigned not_eol : 1;
368
369 /* If true, an anchor at a newline matches. */
370 unsigned newline_anchor : 1;
371
372/* [[[end pattern_buffer]]] */
373};
374
375typedef struct re_pattern_buffer regex_t;
376
377/* Type for byte offsets within the string. POSIX mandates this. */
378typedef int regoff_t;
379
380
381/* This is the structure we store register match data in. See
382 regex.texinfo for a full description of what registers match. */
383struct re_registers
384{
385 unsigned num_regs;
386 regoff_t *start;
387 regoff_t *end;
388};
389
390
391/* If `regs_allocated' is REGS_UNALLOCATED in the pattern buffer,
392 `re_match_2' returns information about at least this many registers
393 the first time a `regs' structure is passed. */
394#ifndef RE_NREGS
395#define RE_NREGS 30
396#endif
397
398
399/* POSIX specification for registers. Aside from the different names than
400 `re_registers', POSIX uses an array of structures, instead of a
401 structure of arrays. */
402typedef struct
403{
404 regoff_t rm_so; /* Byte offset from string's start to substring's start. */
405 regoff_t rm_eo; /* Byte offset from string's start to substring's end. */
406} regmatch_t;
407
408/* Declarations for routines. */
409
410/* To avoid duplicating every routine declaration -- once with a
411 prototype (if we are ANSI), and once without (if we aren't) -- we
412 use the following macro to declare argument types. This
413 unfortunately clutters up the declarations a bit, but I think it's
414 worth it. */
415
416#if __STDC__
417
418#define _RE_ARGS(args) args
419
420#else /* not __STDC__ */
421
422#define _RE_ARGS(args) ()
423
424#endif /* not __STDC__ */
425
426/* Sets the current default syntax to SYNTAX, and return the old syntax.
427 You can also simply assign to the `re_syntax_options' variable. */
maxwen27116ba2015-08-14 21:41:28 +0200428extern reg_syntax_t bb_re_set_syntax _RE_ARGS ((reg_syntax_t syntax));
Tanguy Pruvot36efc942011-11-20 14:41:41 +0100429
430/* Compile the regular expression PATTERN, with length LENGTH
431 and syntax given by the global `re_syntax_options', into the buffer
432 BUFFER. Return NULL if successful, and an error string if not. */
maxwen27116ba2015-08-14 21:41:28 +0200433extern const char *bb_re_compile_pattern
Tanguy Pruvot36efc942011-11-20 14:41:41 +0100434 _RE_ARGS ((const char *pattern, int length,
435 struct re_pattern_buffer *buffer));
436
437
438/* Compile a fastmap for the compiled pattern in BUFFER; used to
439 accelerate searches. Return 0 if successful and -2 if was an
440 internal error. */
maxwen27116ba2015-08-14 21:41:28 +0200441extern int bb_re_compile_fastmap _RE_ARGS ((struct re_pattern_buffer *buffer));
Tanguy Pruvot36efc942011-11-20 14:41:41 +0100442
443
444/* Search in the string STRING (with length LENGTH) for the pattern
445 compiled into BUFFER. Start searching at position START, for RANGE
446 characters. Return the starting position of the match, -1 for no
447 match, or -2 for an internal error. Also return register
448 information in REGS (if REGS and BUFFER->no_sub are nonzero). */
maxwen27116ba2015-08-14 21:41:28 +0200449extern int bb_re_search
Tanguy Pruvot36efc942011-11-20 14:41:41 +0100450 _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string,
451 int length, int start, int range, struct re_registers *regs));
452
453
454/* Like `re_search', but search in the concatenation of STRING1 and
455 STRING2. Also, stop searching at index START + STOP. */
maxwen27116ba2015-08-14 21:41:28 +0200456extern int bb_re_search_2
Tanguy Pruvot36efc942011-11-20 14:41:41 +0100457 _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string1,
458 int length1, const char *string2, int length2,
459 int start, int range, struct re_registers *regs, int stop));
460
461
462/* Like `re_search', but return how many characters in STRING the regexp
463 in BUFFER matched, starting at position START. */
maxwen27116ba2015-08-14 21:41:28 +0200464extern int bb_re_match
Tanguy Pruvot36efc942011-11-20 14:41:41 +0100465 _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string,
466 int length, int start, struct re_registers *regs));
467
468
469/* Relates to `re_match' as `re_search_2' relates to `re_search'. */
maxwen27116ba2015-08-14 21:41:28 +0200470extern int bb_re_match_2
Tanguy Pruvot36efc942011-11-20 14:41:41 +0100471 _RE_ARGS ((struct re_pattern_buffer *buffer, const char *string1,
472 int length1, const char *string2, int length2,
473 int start, struct re_registers *regs, int stop));
474
475
476/* Set REGS to hold NUM_REGS registers, storing them in STARTS and
477 ENDS. Subsequent matches using BUFFER and REGS will use this memory
478 for recording register information. STARTS and ENDS must be
479 allocated with malloc, and must each be at least `NUM_REGS * sizeof
480 (regoff_t)' bytes long.
481
482 If NUM_REGS == 0, then subsequent matches should allocate their own
483 register data.
484
485 Unless this function is called, the first search or match using
486 PATTERN_BUFFER will allocate its own register data, without
487 freeing the old data. */
maxwen27116ba2015-08-14 21:41:28 +0200488extern void bb_re_set_registers
Tanguy Pruvot36efc942011-11-20 14:41:41 +0100489 _RE_ARGS ((struct re_pattern_buffer *buffer, struct re_registers *regs,
490 unsigned num_regs, regoff_t *starts, regoff_t *ends));
491
492#ifdef _REGEX_RE_COMP
493/* 4.2 bsd compatibility. */
maxwen27116ba2015-08-14 21:41:28 +0200494extern char *bb_re_comp _RE_ARGS ((const char *));
495extern int bb_re_exec _RE_ARGS ((const char *));
Tanguy Pruvot36efc942011-11-20 14:41:41 +0100496#endif
497
498/* POSIX compatibility. */
maxwen27116ba2015-08-14 21:41:28 +0200499extern int bb_regcomp _RE_ARGS ((regex_t *preg, const char *pattern, int cflags));
500extern int bb_regexec
Tanguy Pruvot36efc942011-11-20 14:41:41 +0100501 _RE_ARGS ((const regex_t *preg, const char *string, size_t nmatch,
502 regmatch_t pmatch[], int eflags));
maxwen27116ba2015-08-14 21:41:28 +0200503extern size_t bb_regerror
Tanguy Pruvot36efc942011-11-20 14:41:41 +0100504 _RE_ARGS ((int errcode, const regex_t *preg, char *errbuf,
505 size_t errbuf_size));
maxwen27116ba2015-08-14 21:41:28 +0200506extern void bb_regfree _RE_ARGS ((regex_t *preg));
Tanguy Pruvot36efc942011-11-20 14:41:41 +0100507
508#endif /* not __REGEXP_LIBRARY_H__ */
509
510/*
511Local variables:
512make-backup-files: t
513version-control: t
514trim-versions-without-asking: nil
515End:
516*/