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9083 replace regex implementation with tre

@@ -1,225 +1,303 @@
 /*
- * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
- * Copyright (c) 1992, 1993, 1994 Henry Spencer.
- * Copyright (c) 1992, 1993, 1994
- *      The Regents of the University of California.  All rights reserved.
+ * Copyright (c) 2001-2009 Ville Laurikari <vl@iki.fi>
+ * All rights reserved.
  *
- * This code is derived from software contributed to Berkeley by
- * Henry Spencer.
- *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
+ *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
+ *
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the University nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
  *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 /*
- * the outer shell of regexec()
- *
- * This file includes engine.c three times, after muchos fiddling with the
- * macros that code uses.  This lets the same code operate on two different
- * representations for state sets and characters.
- */
-#include "lint.h"
-#include "file64.h"
-#include <sys/types.h>
-#include <stdio.h>
+  tre_regexec.c - TRE POSIX compatible matching functions (and more).
+*/
+
+#include <assert.h>
+#include <limits.h>
 #include <stdlib.h>
 #include <string.h>
-#include <limits.h>
-#include <ctype.h>
-#include <regex.h>
 #include <wchar.h>
 #include <wctype.h>
-#include <note.h>
-#include <assert.h>
 
-#include "utils.h"
-#include "regex2.h"
+#include "tre-internal.h"
+#include "tre-match-utils.h"
+#include "tre.h"
 
-/* we want _NOTE, but not NOTE (which collides with our own use) */
-#undef  NOTE
-
-static size_t
-xmbrtowc(wint_t *wi, const char *s, size_t n, mbstate_t *mbs, wint_t dummy)
+/* 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)
 {
-        size_t nr;
-        wchar_t wc;
+  int max, i, reset;
+  tre_last_matched_branch_t *b;
 
-        nr = mbrtowc(&wc, s, n, mbs);
-        if (wi != NULL)
-                *wi = wc;
-        if (nr == 0)
-                return (1);
-        else if (nr == (size_t)-1 || nr == (size_t)-2) {
-                (void) memset(mbs, 0, sizeof (*mbs));
-                if (wi != NULL)
-                        *wi = dummy;
-                return (1);
-        } else
-                return (nr);
+  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);
+            }
+        }
+    }
 }
 
-static size_t
-xmbrtowc_dummy(wint_t *wi, const char *s, size_t n, mbstate_t *mbs,
-    wint_t dummy)
+/* 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)
 {
-        _NOTE(ARGUNUSED(n));
-        _NOTE(ARGUNUSED(mbs));
-        _NOTE(ARGUNUSED(dummy));
+  unsigned int i;
 
-        if (wi != NULL)
-                *wi = (unsigned char)*s;
-        return (1);
-}
+  if (cflags & REG_NOSUB) return REG_OK;
 
-/* macros for manipulating states, small version */
-#define states  long
-#define states1 states          /* for later use in regexec() decision */
-#define CLEAR(v)        ((v) = 0)
-#define SET0(v, n)      ((v) &= ~((unsigned long)1 << (n)))
-#define SET1(v, n)      ((v) |= (unsigned long)1 << (n))
-#define ISSET(v, n)     (((v) & ((unsigned long)1 << (n))) != 0)
-#define ASSIGN(d, s)    ((d) = (s))
-#define EQ(a, b)        ((a) == (b))
-#define STATEVARS       long dummy      /* dummy version */
-#define STATESETUP(m, n)        /* nothing */
-#define STATETEARDOWN(m)        /* nothing */
-#define SETUP(v)        ((v) = 0)
-#define onestate        long
-#define INIT(o, n)      ((o) = (unsigned long)1 << (n))
-#define INC(o)  ((o) <<= 1)
-#define ISSTATEIN(v, o) (((v) & (o)) != 0)
-/* some abbreviations; note that some of these know variable names! */
-/* do "if I'm here, I can also be there" etc without branches */
-#define FWD(dst, src, n)        ((dst) |= ((unsigned long)(src)&(here)) << (n))
-#define BACK(dst, src, n)       ((dst) |= ((unsigned long)(src)&(here)) >> (n))
-#define ISSETBACK(v, n) (((v) & ((unsigned long)here >> (n))) != 0)
-/* no multibyte support */
-#define XMBRTOWC        xmbrtowc_dummy
-#define ZAPSTATE(mbs)   ((void)(mbs))
-/* function names */
-#define SNAMES                  /* engine.c looks after details */
+  i = 0;
+  if (match_eo >= 0 && intags)
+    {
+      const tre_tag_t *tags = intags;
+      tre_submatch_data_t *submatch_data;
 
-#include "engine.c"
+      if (tnfa->last_matched_branch &&
+          tnfa->last_matched_branch->n_last_matched > 0)
+        {
+          tre_tag_t *t;
+          t = malloc(sizeof(*t) * tnfa->num_tags);
+          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);
 
-/* now undo things */
-#undef  states
-#undef  CLEAR
-#undef  SET0
-#undef  SET1
-#undef  ISSET
-#undef  ASSIGN
-#undef  EQ
-#undef  STATEVARS
-#undef  STATESETUP
-#undef  STATETEARDOWN
-#undef  SETUP
-#undef  onestate
-#undef  INIT
-#undef  INC
-#undef  ISSTATEIN
-#undef  FWD
-#undef  BACK
-#undef  ISSETBACK
-#undef  SNAMES
-#undef  XMBRTOWC
-#undef  ZAPSTATE
+          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);
 
-/* macros for manipulating states, large version */
-#define states  char *
-#define CLEAR(v)        (void) memset(v, 0, m->g->nstates)
-#define SET0(v, n)      ((v)[n] = 0)
-#define SET1(v, n)      ((v)[n] = 1)
-#define ISSET(v, n)     ((v)[n])
-#define ASSIGN(d, s)    (void) memcpy(d, s, m->g->nstates)
-#define EQ(a, b)        (memcmp(a, b, m->g->nstates) == 0)
-#define STATEVARS       long vn; char *space
-#define STATESETUP(m, nv) { (m)->space = malloc((nv)*(m)->g->nstates); \
-        if ((m)->space == NULL) \
-                return (REG_ESPACE); \
-        (m)->vn = 0; }
-#define STATETEARDOWN(m)        { free((m)->space); }
-#define SETUP(v)        ((v) = &m->space[m->vn++ * m->g->nstates])
-#define onestate        long
-#define INIT(o, n)      ((o) = (n))
-#define INC(o)  ((o)++)
-#define ISSTATEIN(v, o) ((v)[o])
-/* some abbreviations; note that some of these know variable names! */
-/* do "if I'm here, I can also be there" etc without branches */
-#define FWD(dst, src, n)        ((dst)[here+(n)] |= (src)[here])
-#define BACK(dst, src, n)       ((dst)[here-(n)] |= (src)[here])
-#define ISSETBACK(v, n) ((v)[here - (n)])
-/* no multibyte support */
-#define XMBRTOWC        xmbrtowc_dummy
-#define ZAPSTATE(mbs)   ((void)(mbs))
-/* function names */
-#define LNAMES                  /* flag */
+          /* 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;
 
-#include "engine.c"
+          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++;
+        }
+        if (tags != intags) free(__DECONST(tre_tag_t *,tags));
+    }
 
-/* multibyte character & large states version */
-#undef  LNAMES
-#undef  XMBRTOWC
-#undef  ZAPSTATE
-#define XMBRTOWC        xmbrtowc
-#define ZAPSTATE(mbs)   (void) memset((mbs), 0, sizeof (*(mbs)))
-#define MNAMES
+  while (i < nmatch)
+    {
+      pmatch[i].rm_so = -1;
+      pmatch[i].rm_eo = -1;
+      i++;
+    }
 
-#include "engine.c"
+  return REG_OK;
+}
 
 /*
- * regexec - interface for matching
- *
- * We put this here so we can exploit knowledge of the state representation
- * when choosing which matcher to call.  Also, by this point the matchers
- * have been prototyped.
- */
-int                             /* 0 success, REG_NOMATCH failure */
-regexec(const regex_t *_RESTRICT_KYWD preg, const char *_RESTRICT_KYWD string,
-    size_t nmatch, regmatch_t pmatch[_RESTRICT_KYWD], int eflags)
+  Wrapper functions for POSIX compatible regexp matching.
+*/
+
+int
+tre_have_backrefs(const regex_t *preg)
 {
-        struct re_guts *g = preg->re_g;
-#ifdef REDEBUG
-#define GOODFLAGS(f)    (f)
+  tre_tnfa_t *tnfa = (void *)preg->TRE_REGEX_T_FIELD;
+  return tnfa->have_backrefs;
+}
+
+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)
+    {
+      tags = malloc(sizeof(*tags) * tnfa->num_tags);
+      if (tags == NULL)
+        return REG_ESPACE;
+    }
+
+  if (
+      (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. */
+#ifdef REG_BACKTRACKING_MATCHER
+  if (tnfa->have_backrefs || eflags & REG_BACKTRACKING_MATCHER)
 #else
-#ifdef  REG_STARTEND
-#define GOODFLAGS(f)    ((f)&(REG_NOTBOL|REG_NOTEOL|REG_STARTEND))
-#else
-#define GOODFLAGS(f)    ((f)&(REG_NOTBOL|REG_NOTEOL))
+  if (tnfa->have_backrefs)
 #endif
-#endif
+    {
+      /* The regex has back references, use the backtracking matcher. */
+      status = tre_tnfa_run_backtrack(tnfa, string + offset, (int)len, type,
+                                      tags, eflags, &eo);
+    }
+  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 (preg->re_magic != MAGIC1 || g->magic != MAGIC2)
-                return (REG_BADPAT);
-        assert(!(g->iflags&BAD));
-        if (g->iflags&BAD)              /* backstop for no-debug case */
-                return (REG_BADPAT);
-        eflags = GOODFLAGS(eflags);
+  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) &&
+          (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;
+            }
+        }
+    }
+  if (tags)
+    free(tags);
+  return status;
+}
 
-        if (MB_CUR_MAX > 1)
-                return (mmatcher(g, string, nmatch, pmatch, eflags));
-        else if (g->nstates <= CHAR_BIT*sizeof (states1) && !(eflags&REG_LARGE))
-                return (smatcher(g, string, nmatch, pmatch, eflags));
-        else
-                return (lmatcher(g, string, nmatch, pmatch, eflags));
+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;
+
+  if (preg->re_magic != RE_MAGIC) return REG_BADPAT;
+
+  return tre_match(tnfa, str, len, type, nmatch, pmatch, eflags);
+}
+
+int
+regexec(const regex_t *_RESTRICT_KYWD preg, const char *_RESTRICT_KYWD str,
+    size_t nmatch, regmatch_t pmatch[_RESTRICT_KYWD], int eflags)
+{
+  return tre_regnexec(preg, str, (size_t)-1, nmatch, pmatch, eflags);
 }