libc/tre: Fix -Wpointer-arith.
[dragonfly.git] / contrib / tre / lib / regexec.c
CommitLineData
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1/*
2 tre_regexec.c - TRE POSIX compatible matching functions (and more).
3
4 This software is released under a BSD-style license.
5 See the file LICENSE for details and copyright.
6
7*/
8
9#ifdef HAVE_CONFIG_H
10#include <config.h>
11#endif /* HAVE_CONFIG_H */
12
13#ifdef TRE_USE_ALLOCA
14/* AIX requires this to be the first thing in the file. */
15#ifndef __GNUC__
16# if HAVE_ALLOCA_H
17# include <alloca.h>
18# else
19# ifdef _AIX
20 #pragma alloca
21# else
22# ifndef alloca /* predefined by HP cc +Olibcalls */
23char *alloca ();
24# endif
25# endif
26# endif
27#endif
28#endif /* TRE_USE_ALLOCA */
29
30#include <assert.h>
31#include <stdlib.h>
32#include <string.h>
33#ifdef HAVE_WCHAR_H
34#include <wchar.h>
35#endif /* HAVE_WCHAR_H */
36#ifdef HAVE_WCTYPE_H
37#include <wctype.h>
38#endif /* HAVE_WCTYPE_H */
39#ifndef TRE_WCHAR
40#include <ctype.h>
41#endif /* !TRE_WCHAR */
42#ifdef HAVE_MALLOC_H
43#include <malloc.h>
44#endif /* HAVE_MALLOC_H */
45#include <limits.h>
46
47#include "tre-internal.h"
d5f8dde1 48#include "tre-match-utils.h"
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49#include "tre.h"
50#include "xmalloc.h"
51
52
d5f8dde1
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53/* For each tre_last_matched_t in the lm array, find the last matched branch by
54 comparing the touch value of the cmp_tag's. For all other branches, reset
55 the corresponding tags. If reset_all is non-zero, reset all tags in all
56 branches. Recurse into the nested last matched structures, clearing tags as
57 apprpriate. */
58static void
59tre_reset_last_matched_branches(tre_tag_t *tags, const tre_last_matched_t *lm,
60 int n, int start_tag, int reset_all)
61{
62 int max, i, reset;
63 tre_last_matched_branch_t *b;
64
65 DPRINT(("tre_reset_last_matched_branches: n=%d start_tag=%d reset_all=%d\n",
66 n, start_tag, reset_all));
67 for (; n-- > 0; lm++)
68 {
69 if (lm->n_branches == 1)
70 {
71 b = lm->branches;
72 if (start_tag > 0)
73 {
74 DPRINT((" b->cmp_tag=%d %d <? %d\n", b->cmp_tag,
75 tre_tag_touch_get(tags, b->cmp_tag),
76 tre_tag_touch_get(tags, start_tag)));
77 reset = (reset_all || tre_tag_touch_get(tags, b->cmp_tag) <
78 tre_tag_touch_get(tags, start_tag));
79 }
80 else
81 reset = 0;
82
83 if (reset)
84 {
85 int *t;
86
87 for (i = b->n_tags, t = b->tags; i > 0; i--, t++)
88 {
89 DPRINT((" Resetting t%d\n", *t));
90 tre_tag_reset(tags, *t);
91 }
92 }
93 if (b->n_last_matched > 0)
94 tre_reset_last_matched_branches(tags, b->last_matched,
95 b->n_last_matched,
96 lm->start_tag, reset);
97 }
98 else
99 {
100 if (!reset_all)
101 {
102#ifdef TRE_DEBUG
103 int last;
104#endif /* TRE_DEBUG */
105 max = 0;
106 for (i = lm->n_branches, b = lm->branches; i > 0; i--, b++)
107 {
108 int t = b->cmp_tag;
109 int touch = tre_tag_touch_get(tags, t);
110 if (touch > max)
111 {
112 max = touch;
113#ifdef TRE_DEBUG
114 last = t;
115#endif /* TRE_DEBUG */
116 }
117 }
118 DPRINT((" Last touched end tag t%d=%d\n", last, max));
119 }
120
121 for (i = lm->n_branches, b = lm->branches; i > 0; i--, b++)
122 {
123 reset = (reset_all || tre_tag_touch_get(tags, b->cmp_tag) < max);
124 if (reset)
125 {
126 int j;
127 int *t;
128
129 for (j = b->n_tags, t = b->tags; j > 0; j--, t++)
130 {
131 DPRINT((" Resetting t%d\n", *t));
132 tre_tag_reset(tags, *t);
133 }
134 }
135 if (b->n_last_matched > 0)
136 tre_reset_last_matched_branches(tags, b->last_matched,
137 b->n_last_matched,
138 lm->start_tag, reset);
139 }
140 }
141 }
142}
143
144
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145/* Fills the POSIX.2 regmatch_t array according to the TNFA tag and match
146 endpoint values. */
d5f8dde1 147reg_errcode_t
5f2eab64 148tre_fill_pmatch(size_t nmatch, regmatch_t pmatch[], int cflags,
d5f8dde1 149 const tre_tnfa_t *tnfa, const tre_tag_t *intags, int match_eo)
5f2eab64 150{
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151 unsigned int i;
152
153 if (cflags & REG_NOSUB) return REG_OK;
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154
155 i = 0;
d5f8dde1 156 if (match_eo >= 0 && intags)
5f2eab64 157 {
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158 const tre_tag_t *tags = intags;
159 tre_submatch_data_t *submatch_data;
160
161 if (tnfa->last_matched_branch &&
162 tnfa->last_matched_branch->n_last_matched > 0)
163 {
164 tre_tag_t *t;
165#ifdef TRE_USE_ALLOCA
166 t = alloca(sizeof(*t) * tnfa->num_tags);
167#else /* !TRE_USE_ALLOCA */
168 t = xmalloc(sizeof(*t) * tnfa->num_tags);
169#endif /* !TRE_USE_ALLOCA */
170 if (!t) return REG_ESPACE;
171 memcpy(t, intags, tnfa->num_tags * sizeof(tre_tag_t));
172 tre_reset_last_matched_branches(t,
173 tnfa->last_matched_branch->last_matched,
174 tnfa->last_matched_branch->n_last_matched,
175 0, 0);
176 tags = t;
177 }
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178 /* Construct submatch offsets from the tags. */
179 DPRINT(("end tag = t%d = %d\n", tnfa->end_tag, match_eo));
180 submatch_data = tnfa->submatch_data;
181 while (i < tnfa->num_submatches && i < nmatch)
182 {
183 if (submatch_data[i].so_tag == tnfa->end_tag)
184 pmatch[i].rm_so = match_eo;
185 else
d5f8dde1 186 pmatch[i].rm_so = tre_tag_get(tags, submatch_data[i].so_tag);
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187
188 if (submatch_data[i].eo_tag == tnfa->end_tag)
189 pmatch[i].rm_eo = match_eo;
190 else
d5f8dde1 191 pmatch[i].rm_eo = tre_tag_get(tags, submatch_data[i].eo_tag);
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192
193 /* If either of the endpoints were not used, this submatch
194 was not part of the match. */
195 if (pmatch[i].rm_so == -1 || pmatch[i].rm_eo == -1)
196 pmatch[i].rm_so = pmatch[i].rm_eo = -1;
197
d5f8dde1 198 DPRINT(("pmatch[%d] = {t%d = %qd, t%d = %qd}\n", i,
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199 submatch_data[i].so_tag, pmatch[i].rm_so,
200 submatch_data[i].eo_tag, pmatch[i].rm_eo));
201 i++;
202 }
d5f8dde1 203#ifndef TRE_USE_ALLOCA
b4603dcf 204 if (tags != intags) xfree(__DECONST(tre_tag_t *,tags));
d5f8dde1 205#endif /* !TRE_USE_ALLOCA */
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206 }
207
208 while (i < nmatch)
209 {
210 pmatch[i].rm_so = -1;
211 pmatch[i].rm_eo = -1;
212 i++;
213 }
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214
215 return REG_OK;
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216}
217
218
219/*
220 Wrapper functions for POSIX compatible regexp matching.
221*/
222
223int
224tre_have_backrefs(const regex_t *preg)
225{
226 tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
227 return tnfa->have_backrefs;
228}
229
d5f8dde1 230#ifdef TRE_APPROX
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231int
232tre_have_approx(const regex_t *preg)
233{
234 tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
235 return tnfa->have_approx;
236}
d5f8dde1 237#endif /* TRE_APPROX */
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238
239static int
240tre_match(const tre_tnfa_t *tnfa, const void *string, size_t len,
241 tre_str_type_t type, size_t nmatch, regmatch_t pmatch[],
242 int eflags)
243{
244 reg_errcode_t status;
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245 tre_tag_t *tags = NULL;
246 int eo;
247 size_t offset = 0, count = 0;
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248 if (tnfa->num_tags > 0 && nmatch > 0)
249 {
250#ifdef TRE_USE_ALLOCA
251 tags = alloca(sizeof(*tags) * tnfa->num_tags);
252#else /* !TRE_USE_ALLOCA */
253 tags = xmalloc(sizeof(*tags) * tnfa->num_tags);
254#endif /* !TRE_USE_ALLOCA */
255 if (tags == NULL)
256 return REG_ESPACE;
257 }
258
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259 if (
260 (eflags & REG_STARTEND) && pmatch)
261 {
262 if (pmatch->rm_so < 0)
263 return REG_INVARG;
264 if (len == (size_t)-1)
265 {
266 if (pmatch->rm_eo < 0 || pmatch->rm_so > pmatch->rm_eo)
267 return REG_INVARG;
268 len = pmatch->rm_eo - pmatch->rm_so;
269 }
270 count = offset = pmatch->rm_so;
271 if (type == STR_WIDE) offset *= sizeof(wchar_t);
272 }
273
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274 /* Dispatch to the appropriate matcher. */
275 if (tnfa->have_backrefs || eflags & REG_BACKTRACKING_MATCHER)
276 {
277 /* The regex has back references, use the backtracking matcher. */
6f872551 278 status = tre_tnfa_run_backtrack(tnfa, (const char *)string + offset, (int)len, type,
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279 tags, eflags, &eo);
280 }
281#ifdef TRE_APPROX
282 else if (tnfa->have_approx || eflags & REG_APPROX_MATCHER)
283 {
284 /* The regex uses approximate matching, use the approximate matcher. */
285 regamatch_t match;
286 regaparams_t params;
287 tre_regaparams_default(&params);
288 params.max_err = 0;
289 params.max_cost = 0;
d5f8dde1 290 status = tre_tnfa_run_approx(tnfa, string + offset, (int)len, type, tags,
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291 &match, params, eflags, &eo);
292 }
293#endif /* TRE_APPROX */
294 else
295 {
296 /* Exact matching, no back references, use the parallel matcher. */
6f872551 297 status = tre_tnfa_run_parallel(tnfa, (const char *)string + offset, (int)len, type,
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298 tags, eflags, &eo);
299 }
300
301 if (status == REG_OK)
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302 {
303 /* A match was found, so fill the submatch registers. */
304 status = tre_fill_pmatch(nmatch, pmatch, tnfa->cflags, tnfa, tags, eo);
305 /* If doing REG_STARTEND, adjust the pmatch array (we can't build
306 this into tre_fill_pmatch, because tre_tnfa_run_backtrack calls
307 tre_fill_pmatch itself). */
308 if (status == REG_OK && !(tnfa->cflags & REG_NOSUB) &&
309 (eflags & REG_STARTEND) && pmatch && nmatch > 0)
310 {
311 size_t i;
312 regmatch_t *p;
313 for (i = nmatch, p = pmatch; i > 0; p++, i--)
314 {
315 if (p->rm_so >= 0) p->rm_so += count;
316 if (p->rm_eo >= 0) p->rm_eo += count;
317 }
318 }
319 }
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320#ifndef TRE_USE_ALLOCA
321 if (tags)
322 xfree(tags);
323#endif /* !TRE_USE_ALLOCA */
324 return status;
325}
326
327int
328tre_regnexec(const regex_t *preg, const char *str, size_t len,
329 size_t nmatch, regmatch_t pmatch[], int eflags)
330{
331 tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
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332 tre_str_type_t type = (TRE_MB_CUR_MAX_L(tnfa->loc) == 1) ? STR_BYTE : STR_MBS;
333
334#ifdef TRE_USE_SYSTEM_REGEX_H
335 if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
336#endif /* TRE_USE_SYSTEM_REGEX_H */
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337
338 return tre_match(tnfa, str, len, type, nmatch, pmatch, eflags);
339}
340
341int
d33005aa
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342tre_regexec(const regex_t * __restrict preg, const char * __restrict str,
343 size_t nmatch, regmatch_t pmatch[__restrict_arr], int eflags)
5f2eab64 344{
d5f8dde1 345 return tre_regnexec(preg, str, (size_t)-1, nmatch, pmatch, eflags);
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346}
347
348
349#ifdef TRE_WCHAR
350
351int
352tre_regwnexec(const regex_t *preg, const wchar_t *str, size_t len,
353 size_t nmatch, regmatch_t pmatch[], int eflags)
354{
355 tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
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356
357#ifdef TRE_USE_SYSTEM_REGEX_H
358 if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
359#endif /* TRE_USE_SYSTEM_REGEX_H */
360
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361 return tre_match(tnfa, str, len, STR_WIDE, nmatch, pmatch, eflags);
362}
363
364int
365tre_regwexec(const regex_t *preg, const wchar_t *str,
366 size_t nmatch, regmatch_t pmatch[], int eflags)
367{
d5f8dde1 368 return tre_regwnexec(preg, str, (size_t)-1, nmatch, pmatch, eflags);
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369}
370
371#endif /* TRE_WCHAR */
372
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373#ifdef TRE_APPROX
374
375/*
376 Wrapper functions for approximate regexp matching.
377*/
378
379static int
380tre_match_approx(const tre_tnfa_t *tnfa, const void *string, size_t len,
381 tre_str_type_t type, regamatch_t *match, regaparams_t params,
382 int eflags)
383{
384 reg_errcode_t status;
d5f8dde1
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385 tre_tag_t *tags = NULL;
386 int eo;
387 size_t offset = 0, count = 0;
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388
389 /* If the regexp does not use approximate matching features, the
390 maximum cost is zero, and the approximate matcher isn't forced,
391 use the exact matcher instead. */
392 if (params.max_cost == 0 && !tnfa->have_approx
393 && !(eflags & REG_APPROX_MATCHER))
394 return tre_match(tnfa, string, len, type, match->nmatch, match->pmatch,
395 eflags);
396
397 /* Back references are not supported by the approximate matcher. */
398 if (tnfa->have_backrefs)
399 return REG_BADPAT;
400
401 if (tnfa->num_tags > 0 && match->nmatch > 0)
402 {
403#if TRE_USE_ALLOCA
404 tags = alloca(sizeof(*tags) * tnfa->num_tags);
405#else /* !TRE_USE_ALLOCA */
406 tags = xmalloc(sizeof(*tags) * tnfa->num_tags);
407#endif /* !TRE_USE_ALLOCA */
408 if (tags == NULL)
409 return REG_ESPACE;
410 }
d5f8dde1
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411
412 if (
413 (eflags & REG_STARTEND) && match->pmatch)
414 {
415 if (match->pmatch->rm_so < 0)
416 return REG_INVARG;
417 if (len == (size_t)-1)
418 {
419 if (match->pmatch->rm_eo < 0 || match->pmatch->rm_so >
420 match->pmatch->rm_eo)
421 return REG_INVARG;
422 len = match->pmatch->rm_eo - match->pmatch->rm_so;
423 }
424 count = offset = match->pmatch->rm_so;
425 if (type == STR_WIDE) offset *= sizeof(wchar_t);
426 }
427
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428 status = tre_tnfa_run_approx(tnfa, string, (int)len, type, tags,
429 match, params, eflags, &eo);
430 if (status == REG_OK)
d5f8dde1
JM
431 {
432 status = tre_fill_pmatch(match->nmatch, match->pmatch, tnfa->cflags,
433 tnfa, tags, eo);
434 /* If doing REG_STARTEND, adjust the pmatch array (we can't build
435 this into tre_fill_pmatch, because tre_tnfa_run_backtrack call
436 tre_fill_pmatch itself). */
437 if (status == REG_OK && !(tnfa->cflags & REG_NOSUB) &&
438 (eflags & REG_STARTEND) && match->pmatch && match->nmatch > 0)
439 {
440 size_t i;
441 regmatch_t *p;
442 for (i = match->nmatch, p = match->pmatch; i > 0; p++, i--)
443 {
444 if (p->rm_so >= 0) p->rm_so += count;
445 if (p->rm_eo >= 0) p->rm_eo += count;
446 }
447 }
448 }
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449#ifndef TRE_USE_ALLOCA
450 if (tags)
451 xfree(tags);
452#endif /* !TRE_USE_ALLOCA */
453 return status;
454}
455
456int
457tre_reganexec(const regex_t *preg, const char *str, size_t len,
458 regamatch_t *match, regaparams_t params, int eflags)
459{
460 tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
d5f8dde1
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461 tre_str_type_t type = (TRE_MB_CUR_MAX_L(tnfa->loc) == 1) ? STR_BYTE : STR_MBS;
462
463#ifdef TRE_USE_SYSTEM_REGEX_H
464 if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
465#endif /* TRE_USE_SYSTEM_REGEX_H */
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466
467 return tre_match_approx(tnfa, str, len, type, match, params, eflags);
468}
469
470int
471tre_regaexec(const regex_t *preg, const char *str,
472 regamatch_t *match, regaparams_t params, int eflags)
473{
d5f8dde1 474 return tre_reganexec(preg, str, (size_t)-1, match, params, eflags);
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475}
476
477#ifdef TRE_WCHAR
478
479int
480tre_regawnexec(const regex_t *preg, const wchar_t *str, size_t len,
481 regamatch_t *match, regaparams_t params, int eflags)
482{
483 tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
d5f8dde1
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484
485#ifdef TRE_USE_SYSTEM_REGEX_H
486 if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
487#endif /* TRE_USE_SYSTEM_REGEX_H */
488
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489 return tre_match_approx(tnfa, str, len, STR_WIDE,
490 match, params, eflags);
491}
492
493int
494tre_regawexec(const regex_t *preg, const wchar_t *str,
495 regamatch_t *match, regaparams_t params, int eflags)
496{
d5f8dde1 497 return tre_regawnexec(preg, str, (size_t)-1, match, params, eflags);
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498}
499
500#endif /* TRE_WCHAR */
501
502void
503tre_regaparams_default(regaparams_t *params)
504{
505 memset(params, 0, sizeof(*params));
506 params->cost_ins = 1;
507 params->cost_del = 1;
508 params->cost_subst = 1;
509 params->max_cost = INT_MAX;
510 params->max_ins = INT_MAX;
511 params->max_del = INT_MAX;
512 params->max_subst = INT_MAX;
513 params->max_err = INT_MAX;
514}
515
516#endif /* TRE_APPROX */
517
518/* EOF */