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-rw-r--r--lib/regexec.c348
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diff --git a/lib/regexec.c b/lib/regexec.c
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+++ b/lib/regexec.c
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+/*
+ 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.h"
+#include "xmalloc.h"
+
+
+/* Fills the POSIX.2 regmatch_t array according to the TNFA tag and match
+ endpoint values. */
+void
+tre_fill_pmatch(size_t nmatch, regmatch_t pmatch[], int cflags,
+ const tre_tnfa_t *tnfa, int *tags, int match_eo)
+{
+ tre_submatch_data_t *submatch_data;
+ unsigned int i, j;
+ int *parents;
+
+ i = 0;
+ if (match_eo >= 0 && !(cflags & REG_NOSUB))
+ {
+ /* 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 = 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 = 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 = %d, t%d = %d}\n", i,
+ submatch_data[i].so_tag, pmatch[i].rm_so,
+ submatch_data[i].eo_tag, pmatch[i].rm_eo));
+ i++;
+ }
+ /* Reset all submatches that are not within all of their parent
+ submatches. */
+ i = 0;
+ while (i < tnfa->num_submatches && i < nmatch)
+ {
+ if (pmatch[i].rm_eo == -1)
+ assert(pmatch[i].rm_so == -1);
+ assert(pmatch[i].rm_so <= pmatch[i].rm_eo);
+
+ parents = submatch_data[i].parents;
+ if (parents != NULL)
+ for (j = 0; parents[j] >= 0; j++)
+ {
+ DPRINT(("pmatch[%d] parent %d\n", i, parents[j]));
+ if (pmatch[i].rm_so < pmatch[parents[j]].rm_so
+ || pmatch[i].rm_eo > pmatch[parents[j]].rm_eo)
+ pmatch[i].rm_so = pmatch[i].rm_eo = -1;
+ }
+ i++;
+ }
+ }
+
+ while (i < nmatch)
+ {
+ pmatch[i].rm_so = -1;
+ pmatch[i].rm_eo = -1;
+ i++;
+ }
+}
+
+
+/*
+ Wrapper functions for POSIX compatible regexp matching.
+*/
+
+int
+tre_have_backrefs(const regex_t *preg)
+{
+ tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
+ return tnfa->have_backrefs;
+}
+
+int
+tre_have_approx(const regex_t *preg)
+{
+ tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
+ return tnfa->have_approx;
+}
+
+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;
+ int *tags = NULL, eo;
+ 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;
+ }
+
+ /* Dispatch to the appropriate matcher. */
+ if (tnfa->have_backrefs || eflags & REG_BACKTRACKING_MATCHER)
+ {
+ /* The regex has back references, use the backtracking matcher. */
+ 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;
+ }
+ status = tre_tnfa_run_backtrack(tnfa, string, (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, (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, (int)len, type,
+ tags, eflags, &eo);
+ }
+
+ if (status == REG_OK)
+ /* A match was found, so fill the submatch registers. */
+ tre_fill_pmatch(nmatch, pmatch, tnfa->cflags, tnfa, tags, eo);
+#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 == 1) ? STR_BYTE : STR_MBS;
+
+ 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, (unsigned)-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;
+ 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, (unsigned)-1, nmatch, pmatch, eflags);
+}
+
+#endif /* TRE_WCHAR */
+
+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;
+ return tre_match(tnfa, str, (unsigned)-1, STR_USER, nmatch, pmatch, eflags);
+}
+
+
+#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;
+ int *tags = NULL, eo;
+
+ /* 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;
+ }
+ status = tre_tnfa_run_approx(tnfa, string, (int)len, type, tags,
+ match, params, eflags, &eo);
+ if (status == REG_OK)
+ tre_fill_pmatch(match->nmatch, match->pmatch, tnfa->cflags, tnfa, tags, eo);
+#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 == 1) ? STR_BYTE : STR_MBS;
+
+ 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, (unsigned)-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;
+ 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, (unsigned)-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 */
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