[apple/libc.git] / regex / TRE / lib / regexec.c

/*
  tre_regexec.c - TRE POSIX compatible matching functions (and more).

  This software is released under a BSD-style license.
  See the file LICENSE for details and copyright.

*/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /* HAVE_CONFIG_H */

#ifdef TRE_USE_ALLOCA
/* AIX requires this to be the first thing in the file.	 */
#ifndef __GNUC__
# if HAVE_ALLOCA_H
#  include <alloca.h>
# else
#  ifdef _AIX
 #pragma alloca
#  else
#   ifndef alloca /* predefined by HP cc +Olibcalls */
char *alloca ();
#   endif
#  endif
# endif
#endif
#endif /* TRE_USE_ALLOCA */

#include <assert.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_WCHAR_H
#include <wchar.h>
#endif /* HAVE_WCHAR_H */
#ifdef HAVE_WCTYPE_H
#include <wctype.h>
#endif /* HAVE_WCTYPE_H */
#ifndef TRE_WCHAR
#include <ctype.h>
#endif /* !TRE_WCHAR */
#ifdef HAVE_MALLOC_H
#include <malloc.h>
#endif /* HAVE_MALLOC_H */
#include <limits.h>

#include "tre-internal.h"
#include "tre-match-utils.h"
#include "tre.h"
#include "xmalloc.h"


/* For each tre_last_matched_t in the lm array, find the last matched branch by
   comparing the touch value of the cmp_tag's.  For all other branches, reset
   the corresponding tags.  If reset_all is non-zero, reset all tags in all
   branches.  Recurse into the nested last matched structures, clearing tags as
   apprpriate. */
static void
tre_reset_last_matched_branches(tre_tag_t *tags, const tre_last_matched_t *lm,
			        int n, int start_tag, int reset_all)
{
  int max, i, reset;
  tre_last_matched_branch_t *b;

  DPRINT(("tre_reset_last_matched_branches: n=%d start_tag=%d reset_all=%d\n",
	  n, start_tag, reset_all));
  for (; n-- > 0; lm++)
    {
      if (lm->n_branches == 1)
	{
	  b = lm->branches;
	  if (start_tag > 0)
	    {
	      DPRINT(("  b->cmp_tag=%d %d <? %d\n", b->cmp_tag,
		      tre_tag_touch_get(tags, b->cmp_tag),
		      tre_tag_touch_get(tags, start_tag)));
	      reset = (reset_all || tre_tag_touch_get(tags, b->cmp_tag) <
		       tre_tag_touch_get(tags, start_tag));
	    }
	  else
	    reset = 0;

	  if (reset)
	    {
	      int *t;

	      for (i = b->n_tags, t = b->tags; i > 0; i--, t++)
		{
		  DPRINT(("  Resetting t%d\n", *t));
		  tre_tag_reset(tags, *t);
		}
	    }
	  if (b->n_last_matched > 0)
	    tre_reset_last_matched_branches(tags, b->last_matched,
						b->n_last_matched, 
						lm->start_tag, reset);
	}
      else
	{
	  if (!reset_all)
	    {
#ifdef TRE_DEBUG
	      int last;
#endif /* TRE_DEBUG */
	      max = 0;
	      for (i = lm->n_branches, b = lm->branches; i > 0; i--, b++)
		{
		  int t = b->cmp_tag;
		  int touch = tre_tag_touch_get(tags, t);
		  if (touch > max)
		    {
		      max = touch;
#ifdef TRE_DEBUG
		      last = t;
#endif /* TRE_DEBUG */
		    }
		}
	      DPRINT(("  Last touched end tag t%d=%d\n", last, max));
	    }

	  for (i = lm->n_branches, b = lm->branches; i > 0; i--, b++)
	    {
	      reset = (reset_all || tre_tag_touch_get(tags, b->cmp_tag) < max);
	      if (reset)
		{
		  int j;
		  int *t;

		  for (j = b->n_tags, t = b->tags; j > 0; j--, t++)
		    {
		      DPRINT(("  Resetting t%d\n", *t));
		      tre_tag_reset(tags, *t);
		    }
		}
	      if (b->n_last_matched > 0)
		tre_reset_last_matched_branches(tags, b->last_matched,
						b->n_last_matched,
						lm->start_tag, reset);
	    }
	}
    }
}


/* Fills the POSIX.2 regmatch_t array according to the TNFA tag and match
   endpoint values. */
reg_errcode_t
tre_fill_pmatch(size_t nmatch, regmatch_t pmatch[], int cflags,
		const tre_tnfa_t *tnfa, const tre_tag_t *intags, int match_eo)
{
  unsigned int i;

  if (cflags & REG_NOSUB) return REG_OK;

  i = 0;
  if (match_eo >= 0 && intags)
    {
      const tre_tag_t *tags = intags;
      tre_submatch_data_t *submatch_data;

      if (tnfa->last_matched_branch &&
	  tnfa->last_matched_branch->n_last_matched > 0)
	{
	  tre_tag_t *t;
#ifdef TRE_USE_ALLOCA
	  t = alloca(sizeof(*t) * tnfa->num_tags);
#else /* !TRE_USE_ALLOCA */
	  t = xmalloc(sizeof(*t) * tnfa->num_tags);
#endif /* !TRE_USE_ALLOCA */
	  if (!t) return REG_ESPACE;
	  memcpy(t, intags, tnfa->num_tags * sizeof(tre_tag_t));
	  tre_reset_last_matched_branches(t,
				    tnfa->last_matched_branch->last_matched,
				    tnfa->last_matched_branch->n_last_matched,
				    0, 0);
	  tags = t;
	}
      /* Construct submatch offsets from the tags. */
      DPRINT(("end tag = t%d = %d\n", tnfa->end_tag, match_eo));
      submatch_data = tnfa->submatch_data;
      while (i < tnfa->num_submatches && i < nmatch)
	{
	  if (submatch_data[i].so_tag == tnfa->end_tag)
	    pmatch[i].rm_so = match_eo;
	  else
	    pmatch[i].rm_so = tre_tag_get(tags, submatch_data[i].so_tag);

	  if (submatch_data[i].eo_tag == tnfa->end_tag)
	    pmatch[i].rm_eo = match_eo;
	  else
	    pmatch[i].rm_eo = tre_tag_get(tags, submatch_data[i].eo_tag);

	  /* If either of the endpoints were not used, this submatch
	     was not part of the match. */
	  if (pmatch[i].rm_so == -1 || pmatch[i].rm_eo == -1)
	    pmatch[i].rm_so = pmatch[i].rm_eo = -1;

	  DPRINT(("pmatch[%d] = {t%d = %qd, t%d = %qd}\n", i,
		  submatch_data[i].so_tag, pmatch[i].rm_so,
		  submatch_data[i].eo_tag, pmatch[i].rm_eo));
	  i++;
	}
#ifndef TRE_USE_ALLOCA
	if (tags != intags) xfree(tags);
#endif /* !TRE_USE_ALLOCA */
    }

  while (i < nmatch)
    {
      pmatch[i].rm_so = -1;
      pmatch[i].rm_eo = -1;
      i++;
    }

  return REG_OK;
}


/*
  Wrapper functions for POSIX compatible regexp matching.
*/

#ifndef __LIBC__
int
tre_have_backrefs(const regex_t *preg)
{
  tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
  return tnfa->have_backrefs;
}

#ifdef TRE_APPROX
int
tre_have_approx(const regex_t *preg)
{
  tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
  return tnfa->have_approx;
}
#endif /* TRE_APPROX */
#endif /* !__LIBC__ */

static int
tre_match(const tre_tnfa_t *tnfa, const void *string, size_t len,
	  tre_str_type_t type, size_t nmatch, regmatch_t pmatch[],
	  int eflags)
{
  reg_errcode_t status;
  tre_tag_t *tags = NULL;
  int eo;
  size_t offset = 0, count = 0;
  if (tnfa->num_tags > 0 && nmatch > 0)
    {
#ifdef TRE_USE_ALLOCA
      tags = alloca(sizeof(*tags) * tnfa->num_tags);
#else /* !TRE_USE_ALLOCA */
      tags = xmalloc(sizeof(*tags) * tnfa->num_tags);
#endif /* !TRE_USE_ALLOCA */
      if (tags == NULL)
	return REG_ESPACE;
    }

  if (
#ifdef TRE_STR_USER
      type != STR_USER &&
#endif /* TRE_STR_USER */
      (eflags & REG_STARTEND) && pmatch)
    {
      if (pmatch->rm_so < 0)
	return REG_INVARG;
      if (len == (size_t)-1)
	{
	  if (pmatch->rm_eo < 0 || pmatch->rm_so > pmatch->rm_eo)
	    return REG_INVARG;
	  len = pmatch->rm_eo - pmatch->rm_so;
	}
      count = offset = pmatch->rm_so;
      if (type == STR_WIDE) offset *= sizeof(wchar_t);
    }

  /* Dispatch to the appropriate matcher. */
  if (tnfa->have_backrefs || eflags & REG_BACKTRACKING_MATCHER)
    {
      /* The regex has back references, use the backtracking matcher. */
#ifdef TRE_STR_USER
      if (type == STR_USER)
	{
	  const tre_str_source *source = string;
	  if (source->rewind == NULL || source->compare == NULL)
	    /* The backtracking matcher requires rewind and compare
	       capabilities from the input stream. */
	    return REG_BADPAT;
	}
#endif /* TRE_STR_USER */
      status = tre_tnfa_run_backtrack(tnfa, string + offset, (int)len, type,
				      tags, eflags, &eo);
    }
#ifdef TRE_APPROX
  else if (tnfa->have_approx || eflags & REG_APPROX_MATCHER)
    {
      /* The regex uses approximate matching, use the approximate matcher. */
      regamatch_t match;
      regaparams_t params;
      tre_regaparams_default(&params);
      params.max_err = 0;
      params.max_cost = 0;
      status = tre_tnfa_run_approx(tnfa, string + offset, (int)len, type, tags,
				   &match, params, eflags, &eo);
    }
#endif /* TRE_APPROX */
  else
    {
      /* Exact matching, no back references, use the parallel matcher. */
      status = tre_tnfa_run_parallel(tnfa, string + offset, (int)len, type,
				     tags, eflags, &eo);
    }

  if (status == REG_OK)
    {
      /* A match was found, so fill the submatch registers. */
      status = tre_fill_pmatch(nmatch, pmatch, tnfa->cflags, tnfa, tags, eo);
      /* If doing REG_STARTEND, adjust the pmatch array (we can't build
         this into tre_fill_pmatch, because tre_tnfa_run_backtrack calls
	 tre_fill_pmatch itself). */
      if (status == REG_OK && !(tnfa->cflags & REG_NOSUB) &&
#ifdef TRE_STR_USER
	  type != STR_USER &&
#endif /* TRE_STR_USER */
	  (eflags & REG_STARTEND) && pmatch && nmatch > 0)
	{
	  size_t i;
	  regmatch_t *p;
	  for (i = nmatch, p = pmatch; i > 0; p++, i--)
	    {
	      if (p->rm_so >= 0) p->rm_so += count;
	      if (p->rm_eo >= 0) p->rm_eo += count;
	    }
	}
    }
#ifndef TRE_USE_ALLOCA
  if (tags)
    xfree(tags);
#endif /* !TRE_USE_ALLOCA */
  return status;
}

int
tre_regnexec(const regex_t *preg, const char *str, size_t len,
	 size_t nmatch, regmatch_t pmatch[], int eflags)
{
  tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
  tre_str_type_t type = (TRE_MB_CUR_MAX_L(tnfa->loc) == 1) ? STR_BYTE : STR_MBS;

#ifdef TRE_USE_SYSTEM_REGEX_H
  if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
#endif /* TRE_USE_SYSTEM_REGEX_H */

  return tre_match(tnfa, str, len, type, nmatch, pmatch, eflags);
}

int
tre_regexec(const regex_t *preg, const char *str,
	size_t nmatch, regmatch_t pmatch[], int eflags)
{
  return tre_regnexec(preg, str, (size_t)-1, nmatch, pmatch, eflags);
}


#ifdef TRE_WCHAR

int
tre_regwnexec(const regex_t *preg, const wchar_t *str, size_t len,
	  size_t nmatch, regmatch_t pmatch[], int eflags)
{
  tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;

#ifdef TRE_USE_SYSTEM_REGEX_H
  if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
#endif /* TRE_USE_SYSTEM_REGEX_H */

  return tre_match(tnfa, str, len, STR_WIDE, nmatch, pmatch, eflags);
}

int
tre_regwexec(const regex_t *preg, const wchar_t *str,
	 size_t nmatch, regmatch_t pmatch[], int eflags)
{
  return tre_regwnexec(preg, str, (size_t)-1, nmatch, pmatch, eflags);
}

#endif /* TRE_WCHAR */

#ifdef TRE_STR_USER
int
tre_reguexec(const regex_t *preg, const tre_str_source *str,
	 size_t nmatch, regmatch_t pmatch[], int eflags)
{
  tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;

#ifdef TRE_USE_SYSTEM_REGEX_H
  if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
#endif /* TRE_USE_SYSTEM_REGEX_H */

  return tre_match(tnfa, str, (size_t)-1, STR_USER, nmatch, pmatch, eflags);
}
#endif /* TRE_STR_USER */


#ifdef TRE_APPROX

/*
  Wrapper functions for approximate regexp matching.
*/

static int
tre_match_approx(const tre_tnfa_t *tnfa, const void *string, size_t len,
		 tre_str_type_t type, regamatch_t *match, regaparams_t params,
		 int eflags)
{
  reg_errcode_t status;
  tre_tag_t *tags = NULL;
  int eo;
  size_t offset = 0, count = 0;

  /* If the regexp does not use approximate matching features, the
     maximum cost is zero, and the approximate matcher isn't forced,
     use the exact matcher instead. */
  if (params.max_cost == 0 && !tnfa->have_approx
      && !(eflags & REG_APPROX_MATCHER))
    return tre_match(tnfa, string, len, type, match->nmatch, match->pmatch,
		     eflags);

  /* Back references are not supported by the approximate matcher. */
  if (tnfa->have_backrefs)
    return REG_BADPAT;

  if (tnfa->num_tags > 0 && match->nmatch > 0)
    {
#if TRE_USE_ALLOCA
      tags = alloca(sizeof(*tags) * tnfa->num_tags);
#else /* !TRE_USE_ALLOCA */
      tags = xmalloc(sizeof(*tags) * tnfa->num_tags);
#endif /* !TRE_USE_ALLOCA */
      if (tags == NULL)
	return REG_ESPACE;
    }

  if (
#ifdef TRE_STR_USER
      type != STR_USER &&
#endif /* TRE_STR_USER */
      (eflags & REG_STARTEND) && match->pmatch)
    {
      if (match->pmatch->rm_so < 0)
	return REG_INVARG;
      if (len == (size_t)-1)
	{
	  if (match->pmatch->rm_eo < 0 || match->pmatch->rm_so >
	      match->pmatch->rm_eo)
	    return REG_INVARG;
	  len = match->pmatch->rm_eo - match->pmatch->rm_so;
	}
      count = offset = match->pmatch->rm_so;
      if (type == STR_WIDE) offset *= sizeof(wchar_t);
    }

  status = tre_tnfa_run_approx(tnfa, string, (int)len, type, tags,
			       match, params, eflags, &eo);
  if (status == REG_OK)
    {
      status = tre_fill_pmatch(match->nmatch, match->pmatch, tnfa->cflags,
			       tnfa, tags, eo);
      /* If doing REG_STARTEND, adjust the pmatch array (we can't build
         this into tre_fill_pmatch, because tre_tnfa_run_backtrack call
	 tre_fill_pmatch itself). */
      if (status == REG_OK && !(tnfa->cflags & REG_NOSUB) &&
#ifdef TRE_STR_USER
	  type != STR_USER &&
#endif /* TRE_STR_USER */
	  (eflags & REG_STARTEND) && match->pmatch && match->nmatch > 0)
	{
	  size_t i;
	  regmatch_t *p;
	  for (i = match->nmatch, p = match->pmatch; i > 0; p++, i--)
	    {
	      if (p->rm_so >= 0) p->rm_so += count;
	      if (p->rm_eo >= 0) p->rm_eo += count;
	    }
	}
    }
#ifndef TRE_USE_ALLOCA
  if (tags)
    xfree(tags);
#endif /* !TRE_USE_ALLOCA */
  return status;
}

int
tre_reganexec(const regex_t *preg, const char *str, size_t len,
	  regamatch_t *match, regaparams_t params, int eflags)
{
  tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
  tre_str_type_t type = (TRE_MB_CUR_MAX_L(tnfa->loc) == 1) ? STR_BYTE : STR_MBS;

#ifdef TRE_USE_SYSTEM_REGEX_H
  if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
#endif /* TRE_USE_SYSTEM_REGEX_H */

  return tre_match_approx(tnfa, str, len, type, match, params, eflags);
}

int
tre_regaexec(const regex_t *preg, const char *str,
	 regamatch_t *match, regaparams_t params, int eflags)
{
  return tre_reganexec(preg, str, (size_t)-1, match, params, eflags);
}

#ifdef TRE_WCHAR

int
tre_regawnexec(const regex_t *preg, const wchar_t *str, size_t len,
	   regamatch_t *match, regaparams_t params, int eflags)
{
  tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;

#ifdef TRE_USE_SYSTEM_REGEX_H
  if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
#endif /* TRE_USE_SYSTEM_REGEX_H */

  return tre_match_approx(tnfa, str, len, STR_WIDE,
			  match, params, eflags);
}

int
tre_regawexec(const regex_t *preg, const wchar_t *str,
	  regamatch_t *match, regaparams_t params, int eflags)
{
  return tre_regawnexec(preg, str, (size_t)-1, match, params, eflags);
}

#endif /* TRE_WCHAR */

void
tre_regaparams_default(regaparams_t *params)
{
  memset(params, 0, sizeof(*params));
  params->cost_ins = 1;
  params->cost_del = 1;
  params->cost_subst = 1;
  params->max_cost = INT_MAX;
  params->max_ins = INT_MAX;
  params->max_del = INT_MAX;
  params->max_subst = INT_MAX;
  params->max_err = INT_MAX;
}

#endif /* TRE_APPROX */

/* EOF */
Commit	Line	Data
ad3c9f2a A	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 */
	23	char *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"
	48	#include "tre-match-utils.h"
	49	#include "tre.h"
	50	#include "xmalloc.h"
	51
	52
	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. */
	58	static void
	59	tre_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
145	/* Fills the POSIX.2 regmatch_t array according to the TNFA tag and match
146	endpoint values. */
147	reg_errcode_t
148	tre_fill_pmatch(size_t nmatch, regmatch_t pmatch[], int cflags,
149	const tre_tnfa_t tnfa, const tre_tag_t intags, int match_eo)
150	{
151	unsigned int i;
152
153	if (cflags & REG_NOSUB) return REG_OK;
154
155	i = 0;
156	if (match_eo >= 0 && intags)
157	{
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	}
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
186	pmatch[i].rm_so = tre_tag_get(tags, submatch_data[i].so_tag);
187
188	if (submatch_data[i].eo_tag == tnfa->end_tag)
189	pmatch[i].rm_eo = match_eo;
190	else
191	pmatch[i].rm_eo = tre_tag_get(tags, submatch_data[i].eo_tag);
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
198	DPRINT(("pmatch[%d] = {t%d = %qd, t%d = %qd}\n", i,
199	submatch_data[i].so_tag, pmatch[i].rm_so,
200	submatch_data[i].eo_tag, pmatch[i].rm_eo));
201	i++;
202	}
203	#ifndef TRE_USE_ALLOCA
204	if (tags != intags) xfree(tags);
205	#endif /* !TRE_USE_ALLOCA */
206	}
207
208	while (i < nmatch)
209	{
210	pmatch[i].rm_so = -1;
211	pmatch[i].rm_eo = -1;
212	i++;
213	}
214
215	return REG_OK;
216	}
217
218
219	/*
220	Wrapper functions for POSIX compatible regexp matching.
221	*/
222
223	#ifndef __LIBC__
224	int
225	tre_have_backrefs(const regex_t *preg)
226	{
227	tre_tnfa_t tnfa = (void )preg->TRE_REGEX_T_FIELD;
228	return tnfa->have_backrefs;
229	}
230
231	#ifdef TRE_APPROX
232	int
233	tre_have_approx(const regex_t *preg)
234	{
235	tre_tnfa_t tnfa = (void )preg->TRE_REGEX_T_FIELD;
236	return tnfa->have_approx;
237	}
238	#endif /* TRE_APPROX */
239	#endif /* !__LIBC__ */
240
241	static int
242	tre_match(const tre_tnfa_t tnfa, const void string, size_t len,
243	tre_str_type_t type, size_t nmatch, regmatch_t pmatch[],
244	int eflags)
245	{
246	reg_errcode_t status;
247	tre_tag_t *tags = NULL;
248	int eo;
249	size_t offset = 0, count = 0;
250	if (tnfa->num_tags > 0 && nmatch > 0)
251	{
252	#ifdef TRE_USE_ALLOCA
253	tags = alloca(sizeof(tags) tnfa->num_tags);
254	#else /* !TRE_USE_ALLOCA */
255	tags = xmalloc(sizeof(tags) tnfa->num_tags);
256	#endif /* !TRE_USE_ALLOCA */
257	if (tags == NULL)
258	return REG_ESPACE;
259	}
260
261	if (
262	#ifdef TRE_STR_USER
263	type != STR_USER &&
264	#endif /* TRE_STR_USER */
265	(eflags & REG_STARTEND) && pmatch)
266	{
267	if (pmatch->rm_so < 0)
268	return REG_INVARG;
269	if (len == (size_t)-1)
270	{
271	if (pmatch->rm_eo < 0 \|\| pmatch->rm_so > pmatch->rm_eo)
272	return REG_INVARG;
273	len = pmatch->rm_eo - pmatch->rm_so;
274	}
275	count = offset = pmatch->rm_so;
276	if (type == STR_WIDE) offset *= sizeof(wchar_t);
277	}
278
279	/* Dispatch to the appropriate matcher. */
280	if (tnfa->have_backrefs \|\| eflags & REG_BACKTRACKING_MATCHER)
281	{
282	/* The regex has back references, use the backtracking matcher. */
283	#ifdef TRE_STR_USER
284	if (type == STR_USER)
285	{
286	const tre_str_source *source = string;
287	if (source->rewind == NULL \|\| source->compare == NULL)
288	/* The backtracking matcher requires rewind and compare
289	capabilities from the input stream. */
290	return REG_BADPAT;
291	}
292	#endif /* TRE_STR_USER */
293	status = tre_tnfa_run_backtrack(tnfa, string + offset, (int)len, type,
294	tags, eflags, &eo);
295	}
296	#ifdef TRE_APPROX
297	else if (tnfa->have_approx \|\| eflags & REG_APPROX_MATCHER)
298	{
299	/* The regex uses approximate matching, use the approximate matcher. */
300	regamatch_t match;
301	regaparams_t params;
302	tre_regaparams_default(&params);
303	params.max_err = 0;
304	params.max_cost = 0;
305	status = tre_tnfa_run_approx(tnfa, string + offset, (int)len, type, tags,
306	&match, params, eflags, &eo);
307	}
308	#endif /* TRE_APPROX */
309	else
310	{
311	/* Exact matching, no back references, use the parallel matcher. */
312	status = tre_tnfa_run_parallel(tnfa, string + offset, (int)len, type,
313	tags, eflags, &eo);
314	}
315
316	if (status == REG_OK)
317	{
318	/* A match was found, so fill the submatch registers. */
319	status = tre_fill_pmatch(nmatch, pmatch, tnfa->cflags, tnfa, tags, eo);
320	/* If doing REG_STARTEND, adjust the pmatch array (we can't build
321	this into tre_fill_pmatch, because tre_tnfa_run_backtrack calls
322	tre_fill_pmatch itself). */
323	if (status == REG_OK && !(tnfa->cflags & REG_NOSUB) &&
324	#ifdef TRE_STR_USER
325	type != STR_USER &&
326	#endif /* TRE_STR_USER */
327	(eflags & REG_STARTEND) && pmatch && nmatch > 0)
328	{
329	size_t i;
330	regmatch_t *p;
331	for (i = nmatch, p = pmatch; i > 0; p++, i--)
332	{
333	if (p->rm_so >= 0) p->rm_so += count;
334	if (p->rm_eo >= 0) p->rm_eo += count;
335	}
336	}
337	}
338	#ifndef TRE_USE_ALLOCA
339	if (tags)
340	xfree(tags);
341	#endif /* !TRE_USE_ALLOCA */
342	return status;
343	}
344
345	int
346	tre_regnexec(const regex_t preg, const char str, size_t len,
347	size_t nmatch, regmatch_t pmatch[], int eflags)
348	{
349	tre_tnfa_t tnfa = (void )preg->TRE_REGEX_T_FIELD;
350	tre_str_type_t type = (TRE_MB_CUR_MAX_L(tnfa->loc) == 1) ? STR_BYTE : STR_MBS;
351
352	#ifdef TRE_USE_SYSTEM_REGEX_H
353	if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
354	#endif /* TRE_USE_SYSTEM_REGEX_H */
355
356	return tre_match(tnfa, str, len, type, nmatch, pmatch, eflags);
357	}
358
359	int
360	tre_regexec(const regex_t preg, const char str,
361	size_t nmatch, regmatch_t pmatch[], int eflags)
362	{
363	return tre_regnexec(preg, str, (size_t)-1, nmatch, pmatch, eflags);
364	}
365
366
367	#ifdef TRE_WCHAR
368
369	int
370	tre_regwnexec(const regex_t preg, const wchar_t str, size_t len,
371	size_t nmatch, regmatch_t pmatch[], int eflags)
372	{
373	tre_tnfa_t tnfa = (void )preg->TRE_REGEX_T_FIELD;
374
375	#ifdef TRE_USE_SYSTEM_REGEX_H
376	if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
377	#endif /* TRE_USE_SYSTEM_REGEX_H */
378
379	return tre_match(tnfa, str, len, STR_WIDE, nmatch, pmatch, eflags);
380	}
381
382	int
383	tre_regwexec(const regex_t preg, const wchar_t str,
384	size_t nmatch, regmatch_t pmatch[], int eflags)
385	{
386	return tre_regwnexec(preg, str, (size_t)-1, nmatch, pmatch, eflags);
387	}
388
389	#endif /* TRE_WCHAR */
390
391	#ifdef TRE_STR_USER
392	int
393	tre_reguexec(const regex_t preg, const tre_str_source str,
394	size_t nmatch, regmatch_t pmatch[], int eflags)
395	{
396	tre_tnfa_t tnfa = (void )preg->TRE_REGEX_T_FIELD;
397
398	#ifdef TRE_USE_SYSTEM_REGEX_H
399	if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
400	#endif /* TRE_USE_SYSTEM_REGEX_H */
401
402	return tre_match(tnfa, str, (size_t)-1, STR_USER, nmatch, pmatch, eflags);
403	}
404	#endif /* TRE_STR_USER */
405
406
407	#ifdef TRE_APPROX
408
409	/*
410	Wrapper functions for approximate regexp matching.
411	*/
412
413	static int
414	tre_match_approx(const tre_tnfa_t tnfa, const void string, size_t len,
415	tre_str_type_t type, regamatch_t *match, regaparams_t params,
416	int eflags)
417	{
418	reg_errcode_t status;
419	tre_tag_t *tags = NULL;
420	int eo;
421	size_t offset = 0, count = 0;
422
423	/* If the regexp does not use approximate matching features, the
424	maximum cost is zero, and the approximate matcher isn't forced,
425	use the exact matcher instead. */
426	if (params.max_cost == 0 && !tnfa->have_approx
427	&& !(eflags & REG_APPROX_MATCHER))
428	return tre_match(tnfa, string, len, type, match->nmatch, match->pmatch,
429	eflags);
430
431	/* Back references are not supported by the approximate matcher. */
432	if (tnfa->have_backrefs)
433	return REG_BADPAT;
434
435	if (tnfa->num_tags > 0 && match->nmatch > 0)
436	{
437	#if TRE_USE_ALLOCA
438	tags = alloca(sizeof(tags) tnfa->num_tags);
439	#else /* !TRE_USE_ALLOCA */
440	tags = xmalloc(sizeof(tags) tnfa->num_tags);
441	#endif /* !TRE_USE_ALLOCA */
442	if (tags == NULL)
443	return REG_ESPACE;
444	}
445
446	if (
447	#ifdef TRE_STR_USER
448	type != STR_USER &&
449	#endif /* TRE_STR_USER */
450	(eflags & REG_STARTEND) && match->pmatch)
451	{
452	if (match->pmatch->rm_so < 0)
453	return REG_INVARG;
454	if (len == (size_t)-1)
455	{
456	if (match->pmatch->rm_eo < 0 \|\| match->pmatch->rm_so >
457	match->pmatch->rm_eo)
458	return REG_INVARG;
459	len = match->pmatch->rm_eo - match->pmatch->rm_so;
460	}
461	count = offset = match->pmatch->rm_so;
462	if (type == STR_WIDE) offset *= sizeof(wchar_t);
463	}
464
465	status = tre_tnfa_run_approx(tnfa, string, (int)len, type, tags,
466	match, params, eflags, &eo);
467	if (status == REG_OK)
468	{
469	status = tre_fill_pmatch(match->nmatch, match->pmatch, tnfa->cflags,
470	tnfa, tags, eo);
471	/* If doing REG_STARTEND, adjust the pmatch array (we can't build
472	this into tre_fill_pmatch, because tre_tnfa_run_backtrack call
473	tre_fill_pmatch itself). */
474	if (status == REG_OK && !(tnfa->cflags & REG_NOSUB) &&
475	#ifdef TRE_STR_USER
476	type != STR_USER &&
477	#endif /* TRE_STR_USER */
478	(eflags & REG_STARTEND) && match->pmatch && match->nmatch > 0)
479	{
480	size_t i;
481	regmatch_t *p;
482	for (i = match->nmatch, p = match->pmatch; i > 0; p++, i--)
483	{
484	if (p->rm_so >= 0) p->rm_so += count;
485	if (p->rm_eo >= 0) p->rm_eo += count;
486	}
487	}
488	}
489	#ifndef TRE_USE_ALLOCA
490	if (tags)
491	xfree(tags);
492	#endif /* !TRE_USE_ALLOCA */
493	return status;
494	}
495
496	int
497	tre_reganexec(const regex_t preg, const char str, size_t len,
498	regamatch_t *match, regaparams_t params, int eflags)
499	{
500	tre_tnfa_t tnfa = (void )preg->TRE_REGEX_T_FIELD;
501	tre_str_type_t type = (TRE_MB_CUR_MAX_L(tnfa->loc) == 1) ? STR_BYTE : STR_MBS;
502
503	#ifdef TRE_USE_SYSTEM_REGEX_H
504	if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
505	#endif /* TRE_USE_SYSTEM_REGEX_H */
506
507	return tre_match_approx(tnfa, str, len, type, match, params, eflags);
508	}
509
510	int
511	tre_regaexec(const regex_t preg, const char str,
512	regamatch_t *match, regaparams_t params, int eflags)
513	{
514	return tre_reganexec(preg, str, (size_t)-1, match, params, eflags);
515	}
516
517	#ifdef TRE_WCHAR
518
519	int
520	tre_regawnexec(const regex_t preg, const wchar_t str, size_t len,
521	regamatch_t *match, regaparams_t params, int eflags)
522	{
523	tre_tnfa_t tnfa = (void )preg->TRE_REGEX_T_FIELD;
524
525	#ifdef TRE_USE_SYSTEM_REGEX_H
526	if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
527	#endif /* TRE_USE_SYSTEM_REGEX_H */
528
529	return tre_match_approx(tnfa, str, len, STR_WIDE,
530	match, params, eflags);
531	}
532
533	int
534	tre_regawexec(const regex_t preg, const wchar_t str,
535	regamatch_t *match, regaparams_t params, int eflags)
536	{
537	return tre_regawnexec(preg, str, (size_t)-1, match, params, eflags);
538	}
539
540	#endif /* TRE_WCHAR */
541
542	void
543	tre_regaparams_default(regaparams_t *params)
544	{
545	memset(params, 0, sizeof(*params));
546	params->cost_ins = 1;
547	params->cost_del = 1;
548	params->cost_subst = 1;
549	params->max_cost = INT_MAX;
550	params->max_ins = INT_MAX;
551	params->max_del = INT_MAX;
552	params->max_subst = INT_MAX;
553	params->max_err = INT_MAX;
554	}
555
556	#endif /* TRE_APPROX */
557
558	/* EOF */