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-rw-r--r--compat/regex/regexec.c4377
1 files changed, 4377 insertions, 0 deletions
diff --git a/compat/regex/regexec.c b/compat/regex/regexec.c
new file mode 100644
index 0000000..aee502d
--- /dev/null
+++ b/compat/regex/regexec.c
@@ -0,0 +1,4377 @@
+/* Extended regular expression matching and search library.
+ Copyright (C) 2002-2005, 2007, 2009, 2010 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ 02110-1301 USA. */
+
+static reg_errcode_t match_ctx_init (re_match_context_t *cache, int eflags,
+ int n) internal_function;
+static void match_ctx_clean (re_match_context_t *mctx) internal_function;
+static void match_ctx_free (re_match_context_t *cache) internal_function;
+static reg_errcode_t match_ctx_add_entry (re_match_context_t *cache, int node,
+ int str_idx, int from, int to)
+ internal_function;
+static int search_cur_bkref_entry (const re_match_context_t *mctx, int str_idx)
+ internal_function;
+static reg_errcode_t match_ctx_add_subtop (re_match_context_t *mctx, int node,
+ int str_idx) internal_function;
+static re_sub_match_last_t * match_ctx_add_sublast (re_sub_match_top_t *subtop,
+ int node, int str_idx)
+ internal_function;
+static void sift_ctx_init (re_sift_context_t *sctx, re_dfastate_t **sifted_sts,
+ re_dfastate_t **limited_sts, int last_node,
+ int last_str_idx)
+ internal_function;
+static reg_errcode_t re_search_internal (const regex_t *preg,
+ const char *string, int length,
+ int start, int range, int stop,
+ size_t nmatch, regmatch_t pmatch[],
+ int eflags) internal_function;
+static int re_search_2_stub (struct re_pattern_buffer *bufp,
+ const char *string1, int length1,
+ const char *string2, int length2,
+ int start, int range, struct re_registers *regs,
+ int stop, int ret_len) internal_function;
+static int re_search_stub (struct re_pattern_buffer *bufp,
+ const char *string, int length, int start,
+ int range, int stop, struct re_registers *regs,
+ int ret_len) internal_function;
+static unsigned re_copy_regs (struct re_registers *regs, regmatch_t *pmatch,
+ int nregs, int regs_allocated) internal_function;
+static reg_errcode_t prune_impossible_nodes (re_match_context_t *mctx)
+ internal_function;
+static int check_matching (re_match_context_t *mctx, int fl_longest_match,
+ int *p_match_first) internal_function;
+static int check_halt_state_context (const re_match_context_t *mctx,
+ const re_dfastate_t *state, int idx)
+ internal_function;
+static void update_regs (const re_dfa_t *dfa, regmatch_t *pmatch,
+ regmatch_t *prev_idx_match, int cur_node,
+ int cur_idx, int nmatch) internal_function;
+static reg_errcode_t push_fail_stack (struct re_fail_stack_t *fs,
+ int str_idx, int dest_node, int nregs,
+ regmatch_t *regs,
+ re_node_set *eps_via_nodes)
+ internal_function;
+static reg_errcode_t set_regs (const regex_t *preg,
+ const re_match_context_t *mctx,
+ size_t nmatch, regmatch_t *pmatch,
+ int fl_backtrack) internal_function;
+static reg_errcode_t free_fail_stack_return (struct re_fail_stack_t *fs)
+ internal_function;
+
+#ifdef RE_ENABLE_I18N
+static int sift_states_iter_mb (const re_match_context_t *mctx,
+ re_sift_context_t *sctx,
+ int node_idx, int str_idx, int max_str_idx)
+ internal_function;
+#endif /* RE_ENABLE_I18N */
+static reg_errcode_t sift_states_backward (const re_match_context_t *mctx,
+ re_sift_context_t *sctx)
+ internal_function;
+static reg_errcode_t build_sifted_states (const re_match_context_t *mctx,
+ re_sift_context_t *sctx, int str_idx,
+ re_node_set *cur_dest)
+ internal_function;
+static reg_errcode_t update_cur_sifted_state (const re_match_context_t *mctx,
+ re_sift_context_t *sctx,
+ int str_idx,
+ re_node_set *dest_nodes)
+ internal_function;
+static reg_errcode_t add_epsilon_src_nodes (const re_dfa_t *dfa,
+ re_node_set *dest_nodes,
+ const re_node_set *candidates)
+ internal_function;
+static int check_dst_limits (const re_match_context_t *mctx,
+ re_node_set *limits,
+ int dst_node, int dst_idx, int src_node,
+ int src_idx) internal_function;
+static int check_dst_limits_calc_pos_1 (const re_match_context_t *mctx,
+ int boundaries, int subexp_idx,
+ int from_node, int bkref_idx)
+ internal_function;
+static int check_dst_limits_calc_pos (const re_match_context_t *mctx,
+ int limit, int subexp_idx,
+ int node, int str_idx,
+ int bkref_idx) internal_function;
+static reg_errcode_t check_subexp_limits (const re_dfa_t *dfa,
+ re_node_set *dest_nodes,
+ const re_node_set *candidates,
+ re_node_set *limits,
+ struct re_backref_cache_entry *bkref_ents,
+ int str_idx) internal_function;
+static reg_errcode_t sift_states_bkref (const re_match_context_t *mctx,
+ re_sift_context_t *sctx,
+ int str_idx, const re_node_set *candidates)
+ internal_function;
+static reg_errcode_t merge_state_array (const re_dfa_t *dfa,
+ re_dfastate_t **dst,
+ re_dfastate_t **src, int num)
+ internal_function;
+static re_dfastate_t *find_recover_state (reg_errcode_t *err,
+ re_match_context_t *mctx) internal_function;
+static re_dfastate_t *transit_state (reg_errcode_t *err,
+ re_match_context_t *mctx,
+ re_dfastate_t *state) internal_function;
+static re_dfastate_t *merge_state_with_log (reg_errcode_t *err,
+ re_match_context_t *mctx,
+ re_dfastate_t *next_state)
+ internal_function;
+static reg_errcode_t check_subexp_matching_top (re_match_context_t *mctx,
+ re_node_set *cur_nodes,
+ int str_idx) internal_function;
+#if 0
+static re_dfastate_t *transit_state_sb (reg_errcode_t *err,
+ re_match_context_t *mctx,
+ re_dfastate_t *pstate)
+ internal_function;
+#endif
+#ifdef RE_ENABLE_I18N
+static reg_errcode_t transit_state_mb (re_match_context_t *mctx,
+ re_dfastate_t *pstate)
+ internal_function;
+#endif /* RE_ENABLE_I18N */
+static reg_errcode_t transit_state_bkref (re_match_context_t *mctx,
+ const re_node_set *nodes)
+ internal_function;
+static reg_errcode_t get_subexp (re_match_context_t *mctx,
+ int bkref_node, int bkref_str_idx)
+ internal_function;
+static reg_errcode_t get_subexp_sub (re_match_context_t *mctx,
+ const re_sub_match_top_t *sub_top,
+ re_sub_match_last_t *sub_last,
+ int bkref_node, int bkref_str)
+ internal_function;
+static int find_subexp_node (const re_dfa_t *dfa, const re_node_set *nodes,
+ int subexp_idx, int type) internal_function;
+static reg_errcode_t check_arrival (re_match_context_t *mctx,
+ state_array_t *path, int top_node,
+ int top_str, int last_node, int last_str,
+ int type) internal_function;
+static reg_errcode_t check_arrival_add_next_nodes (re_match_context_t *mctx,
+ int str_idx,
+ re_node_set *cur_nodes,
+ re_node_set *next_nodes)
+ internal_function;
+static reg_errcode_t check_arrival_expand_ecl (const re_dfa_t *dfa,
+ re_node_set *cur_nodes,
+ int ex_subexp, int type)
+ internal_function;
+static reg_errcode_t check_arrival_expand_ecl_sub (const re_dfa_t *dfa,
+ re_node_set *dst_nodes,
+ int target, int ex_subexp,
+ int type) internal_function;
+static reg_errcode_t expand_bkref_cache (re_match_context_t *mctx,
+ re_node_set *cur_nodes, int cur_str,
+ int subexp_num, int type)
+ internal_function;
+static int build_trtable (const re_dfa_t *dfa,
+ re_dfastate_t *state) internal_function;
+#ifdef RE_ENABLE_I18N
+static int check_node_accept_bytes (const re_dfa_t *dfa, int node_idx,
+ const re_string_t *input, int idx)
+ internal_function;
+# ifdef _LIBC
+static unsigned int find_collation_sequence_value (const unsigned char *mbs,
+ size_t name_len)
+ internal_function;
+# endif /* _LIBC */
+#endif /* RE_ENABLE_I18N */
+static int group_nodes_into_DFAstates (const re_dfa_t *dfa,
+ const re_dfastate_t *state,
+ re_node_set *states_node,
+ bitset_t *states_ch) internal_function;
+static int check_node_accept (const re_match_context_t *mctx,
+ const re_token_t *node, int idx)
+ internal_function;
+static reg_errcode_t extend_buffers (re_match_context_t *mctx)
+ internal_function;
+
+/* Entry point for POSIX code. */
+
+/* regexec searches for a given pattern, specified by PREG, in the
+ string STRING.
+
+ If NMATCH is zero or REG_NOSUB was set in the cflags argument to
+ `regcomp', we ignore PMATCH. Otherwise, we assume PMATCH has at
+ least NMATCH elements, and we set them to the offsets of the
+ corresponding matched substrings.
+
+ EFLAGS specifies `execution flags' which affect matching: if
+ REG_NOTBOL is set, then ^ does not match at the beginning of the
+ string; if REG_NOTEOL is set, then $ does not match at the end.
+
+ We return 0 if we find a match and REG_NOMATCH if not. */
+
+int
+regexec (preg, string, nmatch, pmatch, eflags)
+ const regex_t *__restrict preg;
+ const char *__restrict string;
+ size_t nmatch;
+ regmatch_t pmatch[];
+ int eflags;
+{
+ reg_errcode_t err;
+ int start, length;
+
+ if (eflags & ~(REG_NOTBOL | REG_NOTEOL | REG_STARTEND))
+ return REG_BADPAT;
+
+ if (eflags & REG_STARTEND)
+ {
+ start = pmatch[0].rm_so;
+ length = pmatch[0].rm_eo;
+ }
+ else
+ {
+ start = 0;
+ length = strlen (string);
+ }
+
+ __libc_lock_lock (dfa->lock);
+ if (preg->no_sub)
+ err = re_search_internal (preg, string, length, start, length - start,
+ length, 0, NULL, eflags);
+ else
+ err = re_search_internal (preg, string, length, start, length - start,
+ length, nmatch, pmatch, eflags);
+ __libc_lock_unlock (dfa->lock);
+ return err != REG_NOERROR;
+}
+
+#ifdef _LIBC
+# include <shlib-compat.h>
+versioned_symbol (libc, __regexec, regexec, GLIBC_2_3_4);
+
+# if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_3_4)
+__typeof__ (__regexec) __compat_regexec;
+
+int
+attribute_compat_text_section
+__compat_regexec (const regex_t *__restrict preg,
+ const char *__restrict string, size_t nmatch,
+ regmatch_t pmatch[], int eflags)
+{
+ return regexec (preg, string, nmatch, pmatch,
+ eflags & (REG_NOTBOL | REG_NOTEOL));
+}
+compat_symbol (libc, __compat_regexec, regexec, GLIBC_2_0);
+# endif
+#endif
+
+/* Entry points for GNU code. */
+
+/* re_match, re_search, re_match_2, re_search_2
+
+ The former two functions operate on STRING with length LENGTH,
+ while the later two operate on concatenation of STRING1 and STRING2
+ with lengths LENGTH1 and LENGTH2, respectively.
+
+ re_match() matches the compiled pattern in BUFP against the string,
+ starting at index START.
+
+ re_search() first tries matching at index START, then it tries to match
+ starting from index START + 1, and so on. The last start position tried
+ is START + RANGE. (Thus RANGE = 0 forces re_search to operate the same
+ way as re_match().)
+
+ The parameter STOP of re_{match,search}_2 specifies that no match exceeding
+ the first STOP characters of the concatenation of the strings should be
+ concerned.
+
+ If REGS is not NULL, and BUFP->no_sub is not set, the offsets of the match
+ and all groups is stroed in REGS. (For the "_2" variants, the offsets are
+ computed relative to the concatenation, not relative to the individual
+ strings.)
+
+ On success, re_match* functions return the length of the match, re_search*
+ return the position of the start of the match. Return value -1 means no
+ match was found and -2 indicates an internal error. */
+
+int
+re_match (bufp, string, length, start, regs)
+ struct re_pattern_buffer *bufp;
+ const char *string;
+ int length, start;
+ struct re_registers *regs;
+{
+ return re_search_stub (bufp, string, length, start, 0, length, regs, 1);
+}
+#ifdef _LIBC
+weak_alias (__re_match, re_match)
+#endif
+
+int
+re_search (bufp, string, length, start, range, regs)
+ struct re_pattern_buffer *bufp;
+ const char *string;
+ int length, start, range;
+ struct re_registers *regs;
+{
+ return re_search_stub (bufp, string, length, start, range, length, regs, 0);
+}
+#ifdef _LIBC
+weak_alias (__re_search, re_search)
+#endif
+
+int
+re_match_2 (bufp, string1, length1, string2, length2, start, regs, stop)
+ struct re_pattern_buffer *bufp;
+ const char *string1, *string2;
+ int length1, length2, start, stop;
+ struct re_registers *regs;
+{
+ return re_search_2_stub (bufp, string1, length1, string2, length2,
+ start, 0, regs, stop, 1);
+}
+#ifdef _LIBC
+weak_alias (__re_match_2, re_match_2)
+#endif
+
+int
+re_search_2 (bufp, string1, length1, string2, length2, start, range, regs, stop)
+ struct re_pattern_buffer *bufp;
+ const char *string1, *string2;
+ int length1, length2, start, range, stop;
+ struct re_registers *regs;
+{
+ return re_search_2_stub (bufp, string1, length1, string2, length2,
+ start, range, regs, stop, 0);
+}
+#ifdef _LIBC
+weak_alias (__re_search_2, re_search_2)
+#endif
+
+static int
+re_search_2_stub (bufp, string1, length1, string2, length2, start, range, regs,
+ stop, ret_len)
+ struct re_pattern_buffer *bufp;
+ const char *string1, *string2;
+ int length1, length2, start, range, stop, ret_len;
+ struct re_registers *regs;
+{
+ const char *str;
+ int rval;
+ int len = length1 + length2;
+ int free_str = 0;
+
+ if (BE (length1 < 0 || length2 < 0 || stop < 0, 0))
+ return -2;
+
+ /* Concatenate the strings. */
+ if (length2 > 0)
+ if (length1 > 0)
+ {
+ char *s = re_malloc (char, len);
+
+ if (BE (s == NULL, 0))
+ return -2;
+ memcpy (s, string1, length1);
+ memcpy (s + length1, string2, length2);
+ str = s;
+ free_str = 1;
+ }
+ else
+ str = string2;
+ else
+ str = string1;
+
+ rval = re_search_stub (bufp, str, len, start, range, stop, regs, ret_len);
+ if (free_str)
+ re_free ((char *) str);
+ return rval;
+}
+
+/* The parameters have the same meaning as those of re_search.
+ Additional parameters:
+ If RET_LEN is nonzero the length of the match is returned (re_match style);
+ otherwise the position of the match is returned. */
+
+static int
+re_search_stub (bufp, string, length, start, range, stop, regs, ret_len)
+ struct re_pattern_buffer *bufp;
+ const char *string;
+ int length, start, range, stop, ret_len;
+ struct re_registers *regs;
+{
+ reg_errcode_t result;
+ regmatch_t *pmatch;
+ int nregs, rval;
+ int eflags = 0;
+
+ /* Check for out-of-range. */
+ if (BE (start < 0 || start > length, 0))
+ return -1;
+ if (BE (start + range > length, 0))
+ range = length - start;
+ else if (BE (start + range < 0, 0))
+ range = -start;
+
+ __libc_lock_lock (dfa->lock);
+
+ eflags |= (bufp->not_bol) ? REG_NOTBOL : 0;
+ eflags |= (bufp->not_eol) ? REG_NOTEOL : 0;
+
+ /* Compile fastmap if we haven't yet. */
+ if (range > 0 && bufp->fastmap != NULL && !bufp->fastmap_accurate)
+ re_compile_fastmap (bufp);
+
+ if (BE (bufp->no_sub, 0))
+ regs = NULL;
+
+ /* We need at least 1 register. */
+ if (regs == NULL)
+ nregs = 1;
+ else if (BE (bufp->regs_allocated == REGS_FIXED &&
+ regs->num_regs < bufp->re_nsub + 1, 0))
+ {
+ nregs = regs->num_regs;
+ if (BE (nregs < 1, 0))
+ {
+ /* Nothing can be copied to regs. */
+ regs = NULL;
+ nregs = 1;
+ }
+ }
+ else
+ nregs = bufp->re_nsub + 1;
+ pmatch = re_malloc (regmatch_t, nregs);
+ if (BE (pmatch == NULL, 0))
+ {
+ rval = -2;
+ goto out;
+ }
+
+ result = re_search_internal (bufp, string, length, start, range, stop,
+ nregs, pmatch, eflags);
+
+ rval = 0;
+
+ /* I hope we needn't fill ther regs with -1's when no match was found. */
+ if (result != REG_NOERROR)
+ rval = -1;
+ else if (regs != NULL)
+ {
+ /* If caller wants register contents data back, copy them. */
+ bufp->regs_allocated = re_copy_regs (regs, pmatch, nregs,
+ bufp->regs_allocated);
+ if (BE (bufp->regs_allocated == REGS_UNALLOCATED, 0))
+ rval = -2;
+ }
+
+ if (BE (rval == 0, 1))
+ {
+ if (ret_len)
+ {
+ assert (pmatch[0].rm_so == start);
+ rval = pmatch[0].rm_eo - start;
+ }
+ else
+ rval = pmatch[0].rm_so;
+ }
+ re_free (pmatch);
+ out:
+ __libc_lock_unlock (dfa->lock);
+ return rval;
+}
+
+static unsigned
+re_copy_regs (regs, pmatch, nregs, regs_allocated)
+ struct re_registers *regs;
+ regmatch_t *pmatch;
+ int nregs, regs_allocated;
+{
+ int rval = REGS_REALLOCATE;
+ int i;
+ int need_regs = nregs + 1;
+ /* We need one extra element beyond `num_regs' for the `-1' marker GNU code
+ uses. */
+
+ /* Have the register data arrays been allocated? */
+ if (regs_allocated == REGS_UNALLOCATED)
+ { /* No. So allocate them with malloc. */
+ regs->start = re_malloc (regoff_t, need_regs);
+ if (BE (regs->start == NULL, 0))
+ return REGS_UNALLOCATED;
+ regs->end = re_malloc (regoff_t, need_regs);
+ if (BE (regs->end == NULL, 0))
+ {
+ re_free (regs->start);
+ return REGS_UNALLOCATED;
+ }
+ regs->num_regs = need_regs;
+ }
+ else if (regs_allocated == REGS_REALLOCATE)
+ { /* Yes. If we need more elements than were already
+ allocated, reallocate them. If we need fewer, just
+ leave it alone. */
+ if (BE (need_regs > regs->num_regs, 0))
+ {
+ regoff_t *new_start = re_realloc (regs->start, regoff_t, need_regs);
+ regoff_t *new_end;
+ if (BE (new_start == NULL, 0))
+ return REGS_UNALLOCATED;
+ new_end = re_realloc (regs->end, regoff_t, need_regs);
+ if (BE (new_end == NULL, 0))
+ {
+ re_free (new_start);
+ return REGS_UNALLOCATED;
+ }
+ regs->start = new_start;
+ regs->end = new_end;
+ regs->num_regs = need_regs;
+ }
+ }
+ else
+ {
+ assert (regs_allocated == REGS_FIXED);
+ /* This function may not be called with REGS_FIXED and nregs too big. */
+ assert (regs->num_regs >= nregs);
+ rval = REGS_FIXED;
+ }
+
+ /* Copy the regs. */
+ for (i = 0; i < nregs; ++i)
+ {
+ regs->start[i] = pmatch[i].rm_so;
+ regs->end[i] = pmatch[i].rm_eo;
+ }
+ for ( ; i < regs->num_regs; ++i)
+ regs->start[i] = regs->end[i] = -1;
+
+ return rval;
+}
+
+/* Set REGS to hold NUM_REGS registers, storing them in STARTS and
+ ENDS. Subsequent matches using PATTERN_BUFFER and REGS will use
+ this memory for recording register information. STARTS and ENDS
+ must be allocated using the malloc library routine, and must each
+ be at least NUM_REGS * sizeof (regoff_t) bytes long.
+
+ If NUM_REGS == 0, then subsequent matches should allocate their own
+ register data.
+
+ Unless this function is called, the first search or match using
+ PATTERN_BUFFER will allocate its own register data, without
+ freeing the old data. */
+
+void
+re_set_registers (bufp, regs, num_regs, starts, ends)
+ struct re_pattern_buffer *bufp;
+ struct re_registers *regs;
+ unsigned num_regs;
+ regoff_t *starts, *ends;
+{
+ if (num_regs)
+ {
+ bufp->regs_allocated = REGS_REALLOCATE;
+ regs->num_regs = num_regs;
+ regs->start = starts;
+ regs->end = ends;
+ }
+ else
+ {
+ bufp->regs_allocated = REGS_UNALLOCATED;
+ regs->num_regs = 0;
+ regs->start = regs->end = (regoff_t *) 0;
+ }
+}
+#ifdef _LIBC
+weak_alias (__re_set_registers, re_set_registers)
+#endif
+
+/* Entry points compatible with 4.2 BSD regex library. We don't define
+ them unless specifically requested. */
+
+#if defined _REGEX_RE_COMP || defined _LIBC
+int
+# ifdef _LIBC
+weak_function
+# endif
+re_exec (s)
+ const char *s;
+{
+ return 0 == regexec (&re_comp_buf, s, 0, NULL, 0);
+}
+#endif /* _REGEX_RE_COMP */
+
+/* Internal entry point. */
+
+/* Searches for a compiled pattern PREG in the string STRING, whose
+ length is LENGTH. NMATCH, PMATCH, and EFLAGS have the same
+ mingings with regexec. START, and RANGE have the same meanings
+ with re_search.
+ Return REG_NOERROR if we find a match, and REG_NOMATCH if not,
+ otherwise return the error code.
+ Note: We assume front end functions already check ranges.
+ (START + RANGE >= 0 && START + RANGE <= LENGTH) */
+
+static reg_errcode_t
+re_search_internal (preg, string, length, start, range, stop, nmatch, pmatch,
+ eflags)
+ const regex_t *preg;
+ const char *string;
+ int length, start, range, stop, eflags;
+ size_t nmatch;
+ regmatch_t pmatch[];
+{
+ reg_errcode_t err;
+ const re_dfa_t *dfa = (const re_dfa_t *) preg->buffer;
+ int left_lim, right_lim, incr;
+ int fl_longest_match, match_first, match_kind, match_last = -1;
+ int extra_nmatch;
+ int sb, ch;
+#if defined _LIBC || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)
+ re_match_context_t mctx = { .dfa = dfa };
+#else
+ re_match_context_t mctx;
+#endif
+ char *fastmap = (preg->fastmap != NULL && preg->fastmap_accurate
+ && range && !preg->can_be_null) ? preg->fastmap : NULL;
+ RE_TRANSLATE_TYPE t = preg->translate;
+
+#if !(defined _LIBC || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L))
+ memset (&mctx, '\0', sizeof (re_match_context_t));
+ mctx.dfa = dfa;
+#endif
+
+ extra_nmatch = (nmatch > preg->re_nsub) ? nmatch - (preg->re_nsub + 1) : 0;
+ nmatch -= extra_nmatch;
+
+ /* Check if the DFA haven't been compiled. */
+ if (BE (preg->used == 0 || dfa->init_state == NULL
+ || dfa->init_state_word == NULL || dfa->init_state_nl == NULL
+ || dfa->init_state_begbuf == NULL, 0))
+ return REG_NOMATCH;
+
+#ifdef DEBUG
+ /* We assume front-end functions already check them. */
+ assert (start + range >= 0 && start + range <= length);
+#endif
+
+ /* If initial states with non-begbuf contexts have no elements,
+ the regex must be anchored. If preg->newline_anchor is set,
+ we'll never use init_state_nl, so do not check it. */
+ if (dfa->init_state->nodes.nelem == 0
+ && dfa->init_state_word->nodes.nelem == 0
+ && (dfa->init_state_nl->nodes.nelem == 0
+ || !preg->newline_anchor))
+ {
+ if (start != 0 && start + range != 0)
+ return REG_NOMATCH;
+ start = range = 0;
+ }
+
+ /* We must check the longest matching, if nmatch > 0. */
+ fl_longest_match = (nmatch != 0 || dfa->nbackref);
+
+ err = re_string_allocate (&mctx.input, string, length, dfa->nodes_len + 1,
+ preg->translate, preg->syntax & RE_ICASE, dfa);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+ mctx.input.stop = stop;
+ mctx.input.raw_stop = stop;
+ mctx.input.newline_anchor = preg->newline_anchor;
+
+ err = match_ctx_init (&mctx, eflags, dfa->nbackref * 2);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+
+ /* We will log all the DFA states through which the dfa pass,
+ if nmatch > 1, or this dfa has "multibyte node", which is a
+ back-reference or a node which can accept multibyte character or
+ multi character collating element. */
+ if (nmatch > 1 || dfa->has_mb_node)
+ {
+ /* Avoid overflow. */
+ if (BE (SIZE_MAX / sizeof (re_dfastate_t *) <= mctx.input.bufs_len, 0))
+ {
+ err = REG_ESPACE;
+ goto free_return;
+ }
+
+ mctx.state_log = re_malloc (re_dfastate_t *, mctx.input.bufs_len + 1);
+ if (BE (mctx.state_log == NULL, 0))
+ {
+ err = REG_ESPACE;
+ goto free_return;
+ }
+ }
+ else
+ mctx.state_log = NULL;
+
+ match_first = start;
+ mctx.input.tip_context = (eflags & REG_NOTBOL) ? CONTEXT_BEGBUF
+ : CONTEXT_NEWLINE | CONTEXT_BEGBUF;
+
+ /* Check incrementally whether of not the input string match. */
+ incr = (range < 0) ? -1 : 1;
+ left_lim = (range < 0) ? start + range : start;
+ right_lim = (range < 0) ? start : start + range;
+ sb = dfa->mb_cur_max == 1;
+ match_kind =
+ (fastmap
+ ? ((sb || !(preg->syntax & RE_ICASE || t) ? 4 : 0)
+ | (range >= 0 ? 2 : 0)
+ | (t != NULL ? 1 : 0))
+ : 8);
+
+ for (;; match_first += incr)
+ {
+ err = REG_NOMATCH;
+ if (match_first < left_lim || right_lim < match_first)
+ goto free_return;
+
+ /* Advance as rapidly as possible through the string, until we
+ find a plausible place to start matching. This may be done
+ with varying efficiency, so there are various possibilities:
+ only the most common of them are specialized, in order to
+ save on code size. We use a switch statement for speed. */
+ switch (match_kind)
+ {
+ case 8:
+ /* No fastmap. */
+ break;
+
+ case 7:
+ /* Fastmap with single-byte translation, match forward. */
+ while (BE (match_first < right_lim, 1)
+ && !fastmap[t[(unsigned char) string[match_first]]])
+ ++match_first;
+ goto forward_match_found_start_or_reached_end;
+
+ case 6:
+ /* Fastmap without translation, match forward. */
+ while (BE (match_first < right_lim, 1)
+ && !fastmap[(unsigned char) string[match_first]])
+ ++match_first;
+
+ forward_match_found_start_or_reached_end:
+ if (BE (match_first == right_lim, 0))
+ {
+ ch = match_first >= length
+ ? 0 : (unsigned char) string[match_first];
+ if (!fastmap[t ? t[ch] : ch])
+ goto free_return;
+ }
+ break;
+
+ case 4:
+ case 5:
+ /* Fastmap without multi-byte translation, match backwards. */
+ while (match_first >= left_lim)
+ {
+ ch = match_first >= length
+ ? 0 : (unsigned char) string[match_first];
+ if (fastmap[t ? t[ch] : ch])
+ break;
+ --match_first;
+ }
+ if (match_first < left_lim)
+ goto free_return;
+ break;
+
+ default:
+ /* In this case, we can't determine easily the current byte,
+ since it might be a component byte of a multibyte
+ character. Then we use the constructed buffer instead. */
+ for (;;)
+ {
+ /* If MATCH_FIRST is out of the valid range, reconstruct the
+ buffers. */
+ unsigned int offset = match_first - mctx.input.raw_mbs_idx;
+ if (BE (offset >= (unsigned int) mctx.input.valid_raw_len, 0))
+ {
+ err = re_string_reconstruct (&mctx.input, match_first,
+ eflags);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+
+ offset = match_first - mctx.input.raw_mbs_idx;
+ }
+ /* If MATCH_FIRST is out of the buffer, leave it as '\0'.
+ Note that MATCH_FIRST must not be smaller than 0. */
+ ch = (match_first >= length
+ ? 0 : re_string_byte_at (&mctx.input, offset));
+ if (fastmap[ch])
+ break;
+ match_first += incr;
+ if (match_first < left_lim || match_first > right_lim)
+ {
+ err = REG_NOMATCH;
+ goto free_return;
+ }
+ }
+ break;
+ }
+
+ /* Reconstruct the buffers so that the matcher can assume that
+ the matching starts from the beginning of the buffer. */
+ err = re_string_reconstruct (&mctx.input, match_first, eflags);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+
+#ifdef RE_ENABLE_I18N
+ /* Don't consider this char as a possible match start if it part,
+ yet isn't the head, of a multibyte character. */
+ if (!sb && !re_string_first_byte (&mctx.input, 0))
+ continue;
+#endif
+
+ /* It seems to be appropriate one, then use the matcher. */
+ /* We assume that the matching starts from 0. */
+ mctx.state_log_top = mctx.nbkref_ents = mctx.max_mb_elem_len = 0;
+ match_last = check_matching (&mctx, fl_longest_match,
+ range >= 0 ? &match_first : NULL);
+ if (match_last != -1)
+ {
+ if (BE (match_last == -2, 0))
+ {
+ err = REG_ESPACE;
+ goto free_return;
+ }
+ else
+ {
+ mctx.match_last = match_last;
+ if ((!preg->no_sub && nmatch > 1) || dfa->nbackref)
+ {
+ re_dfastate_t *pstate = mctx.state_log[match_last];
+ mctx.last_node = check_halt_state_context (&mctx, pstate,
+ match_last);
+ }
+ if ((!preg->no_sub && nmatch > 1 && dfa->has_plural_match)
+ || dfa->nbackref)
+ {
+ err = prune_impossible_nodes (&mctx);
+ if (err == REG_NOERROR)
+ break;
+ if (BE (err != REG_NOMATCH, 0))
+ goto free_return;
+ match_last = -1;
+ }
+ else
+ break; /* We found a match. */
+ }
+ }
+
+ match_ctx_clean (&mctx);
+ }
+
+#ifdef DEBUG
+ assert (match_last != -1);
+ assert (err == REG_NOERROR);
+#endif
+
+ /* Set pmatch[] if we need. */
+ if (nmatch > 0)
+ {
+ int reg_idx;
+
+ /* Initialize registers. */
+ for (reg_idx = 1; reg_idx < nmatch; ++reg_idx)
+ pmatch[reg_idx].rm_so = pmatch[reg_idx].rm_eo = -1;
+
+ /* Set the points where matching start/end. */
+ pmatch[0].rm_so = 0;
+ pmatch[0].rm_eo = mctx.match_last;
+
+ if (!preg->no_sub && nmatch > 1)
+ {
+ err = set_regs (preg, &mctx, nmatch, pmatch,
+ dfa->has_plural_match && dfa->nbackref > 0);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+ }
+
+ /* At last, add the offset to the each registers, since we slided
+ the buffers so that we could assume that the matching starts
+ from 0. */
+ for (reg_idx = 0; reg_idx < nmatch; ++reg_idx)
+ if (pmatch[reg_idx].rm_so != -1)
+ {
+#ifdef RE_ENABLE_I18N
+ if (BE (mctx.input.offsets_needed != 0, 0))
+ {
+ pmatch[reg_idx].rm_so =
+ (pmatch[reg_idx].rm_so == mctx.input.valid_len
+ ? mctx.input.valid_raw_len
+ : mctx.input.offsets[pmatch[reg_idx].rm_so]);
+ pmatch[reg_idx].rm_eo =
+ (pmatch[reg_idx].rm_eo == mctx.input.valid_len
+ ? mctx.input.valid_raw_len
+ : mctx.input.offsets[pmatch[reg_idx].rm_eo]);
+ }
+#else
+ assert (mctx.input.offsets_needed == 0);
+#endif
+ pmatch[reg_idx].rm_so += match_first;
+ pmatch[reg_idx].rm_eo += match_first;
+ }
+ for (reg_idx = 0; reg_idx < extra_nmatch; ++reg_idx)
+ {
+ pmatch[nmatch + reg_idx].rm_so = -1;
+ pmatch[nmatch + reg_idx].rm_eo = -1;
+ }
+
+ if (dfa->subexp_map)
+ for (reg_idx = 0; reg_idx + 1 < nmatch; reg_idx++)
+ if (dfa->subexp_map[reg_idx] != reg_idx)
+ {
+ pmatch[reg_idx + 1].rm_so
+ = pmatch[dfa->subexp_map[reg_idx] + 1].rm_so;
+ pmatch[reg_idx + 1].rm_eo
+ = pmatch[dfa->subexp_map[reg_idx] + 1].rm_eo;
+ }
+ }
+
+ free_return:
+ re_free (mctx.state_log);
+ if (dfa->nbackref)
+ match_ctx_free (&mctx);
+ re_string_destruct (&mctx.input);
+ return err;
+}
+
+static reg_errcode_t
+prune_impossible_nodes (mctx)
+ re_match_context_t *mctx;
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ int halt_node, match_last;
+ reg_errcode_t ret;
+ re_dfastate_t **sifted_states;
+ re_dfastate_t **lim_states = NULL;
+ re_sift_context_t sctx;
+#ifdef DEBUG
+ assert (mctx->state_log != NULL);
+#endif
+ match_last = mctx->match_last;
+ halt_node = mctx->last_node;
+
+ /* Avoid overflow. */
+ if (BE (SIZE_MAX / sizeof (re_dfastate_t *) <= match_last, 0))
+ return REG_ESPACE;
+
+ sifted_states = re_malloc (re_dfastate_t *, match_last + 1);
+ if (BE (sifted_states == NULL, 0))
+ {
+ ret = REG_ESPACE;
+ goto free_return;
+ }
+ if (dfa->nbackref)
+ {
+ lim_states = re_malloc (re_dfastate_t *, match_last + 1);
+ if (BE (lim_states == NULL, 0))
+ {
+ ret = REG_ESPACE;
+ goto free_return;
+ }
+ while (1)
+ {
+ memset (lim_states, '\0',
+ sizeof (re_dfastate_t *) * (match_last + 1));
+ sift_ctx_init (&sctx, sifted_states, lim_states, halt_node,
+ match_last);
+ ret = sift_states_backward (mctx, &sctx);
+ re_node_set_free (&sctx.limits);
+ if (BE (ret != REG_NOERROR, 0))
+ goto free_return;
+ if (sifted_states[0] != NULL || lim_states[0] != NULL)
+ break;
+ do
+ {
+ --match_last;
+ if (match_last < 0)
+ {
+ ret = REG_NOMATCH;
+ goto free_return;
+ }
+ } while (mctx->state_log[match_last] == NULL
+ || !mctx->state_log[match_last]->halt);
+ halt_node = check_halt_state_context (mctx,
+ mctx->state_log[match_last],
+ match_last);
+ }
+ ret = merge_state_array (dfa, sifted_states, lim_states,
+ match_last + 1);
+ re_free (lim_states);
+ lim_states = NULL;
+ if (BE (ret != REG_NOERROR, 0))
+ goto free_return;
+ }
+ else
+ {
+ sift_ctx_init (&sctx, sifted_states, lim_states, halt_node, match_last);
+ ret = sift_states_backward (mctx, &sctx);
+ re_node_set_free (&sctx.limits);
+ if (BE (ret != REG_NOERROR, 0))
+ goto free_return;
+ if (sifted_states[0] == NULL)
+ {
+ ret = REG_NOMATCH;
+ goto free_return;
+ }
+ }
+ re_free (mctx->state_log);
+ mctx->state_log = sifted_states;
+ sifted_states = NULL;
+ mctx->last_node = halt_node;
+ mctx->match_last = match_last;
+ ret = REG_NOERROR;
+ free_return:
+ re_free (sifted_states);
+ re_free (lim_states);
+ return ret;
+}
+
+/* Acquire an initial state and return it.
+ We must select appropriate initial state depending on the context,
+ since initial states may have constraints like "\<", "^", etc.. */
+
+static inline re_dfastate_t *
+__attribute ((always_inline)) internal_function
+acquire_init_state_context (reg_errcode_t *err, const re_match_context_t *mctx,
+ int idx)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ if (dfa->init_state->has_constraint)
+ {
+ unsigned int context;
+ context = re_string_context_at (&mctx->input, idx - 1, mctx->eflags);
+ if (IS_WORD_CONTEXT (context))
+ return dfa->init_state_word;
+ else if (IS_ORDINARY_CONTEXT (context))
+ return dfa->init_state;
+ else if (IS_BEGBUF_CONTEXT (context) && IS_NEWLINE_CONTEXT (context))
+ return dfa->init_state_begbuf;
+ else if (IS_NEWLINE_CONTEXT (context))
+ return dfa->init_state_nl;
+ else if (IS_BEGBUF_CONTEXT (context))
+ {
+ /* It is relatively rare case, then calculate on demand. */
+ return re_acquire_state_context (err, dfa,
+ dfa->init_state->entrance_nodes,
+ context);
+ }
+ else
+ /* Must not happen? */
+ return dfa->init_state;
+ }
+ else
+ return dfa->init_state;
+}
+
+/* Check whether the regular expression match input string INPUT or not,
+ and return the index where the matching end, return -1 if not match,
+ or return -2 in case of an error.
+ FL_LONGEST_MATCH means we want the POSIX longest matching.
+ If P_MATCH_FIRST is not NULL, and the match fails, it is set to the
+ next place where we may want to try matching.
+ Note that the matcher assume that the maching starts from the current
+ index of the buffer. */
+
+static int
+internal_function
+check_matching (re_match_context_t *mctx, int fl_longest_match,
+ int *p_match_first)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ reg_errcode_t err;
+ int match = 0;
+ int match_last = -1;
+ int cur_str_idx = re_string_cur_idx (&mctx->input);
+ re_dfastate_t *cur_state;
+ int at_init_state = p_match_first != NULL;
+ int next_start_idx = cur_str_idx;
+
+ err = REG_NOERROR;
+ cur_state = acquire_init_state_context (&err, mctx, cur_str_idx);
+ /* An initial state must not be NULL (invalid). */
+ if (BE (cur_state == NULL, 0))
+ {
+ assert (err == REG_ESPACE);
+ return -2;
+ }
+
+ if (mctx->state_log != NULL)
+ {
+ mctx->state_log[cur_str_idx] = cur_state;
+
+ /* Check OP_OPEN_SUBEXP in the initial state in case that we use them
+ later. E.g. Processing back references. */
+ if (BE (dfa->nbackref, 0))
+ {
+ at_init_state = 0;
+ err = check_subexp_matching_top (mctx, &cur_state->nodes, 0);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+
+ if (cur_state->has_backref)
+ {
+ err = transit_state_bkref (mctx, &cur_state->nodes);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+ }
+ }
+
+ /* If the RE accepts NULL string. */
+ if (BE (cur_state->halt, 0))
+ {
+ if (!cur_state->has_constraint
+ || check_halt_state_context (mctx, cur_state, cur_str_idx))
+ {
+ if (!fl_longest_match)
+ return cur_str_idx;
+ else
+ {
+ match_last = cur_str_idx;
+ match = 1;
+ }
+ }
+ }
+
+ while (!re_string_eoi (&mctx->input))
+ {
+ re_dfastate_t *old_state = cur_state;
+ int next_char_idx = re_string_cur_idx (&mctx->input) + 1;
+
+ if (BE (next_char_idx >= mctx->input.bufs_len, 0)
+ || (BE (next_char_idx >= mctx->input.valid_len, 0)
+ && mctx->input.valid_len < mctx->input.len))
+ {
+ err = extend_buffers (mctx);
+ if (BE (err != REG_NOERROR, 0))
+ {
+ assert (err == REG_ESPACE);
+ return -2;
+ }
+ }
+
+ cur_state = transit_state (&err, mctx, cur_state);
+ if (mctx->state_log != NULL)
+ cur_state = merge_state_with_log (&err, mctx, cur_state);
+
+ if (cur_state == NULL)
+ {
+ /* Reached the invalid state or an error. Try to recover a valid
+ state using the state log, if available and if we have not
+ already found a valid (even if not the longest) match. */
+ if (BE (err != REG_NOERROR, 0))
+ return -2;
+
+ if (mctx->state_log == NULL
+ || (match && !fl_longest_match)
+ || (cur_state = find_recover_state (&err, mctx)) == NULL)
+ break;
+ }
+
+ if (BE (at_init_state, 0))
+ {
+ if (old_state == cur_state)
+ next_start_idx = next_char_idx;
+ else
+ at_init_state = 0;
+ }
+
+ if (cur_state->halt)
+ {
+ /* Reached a halt state.
+ Check the halt state can satisfy the current context. */
+ if (!cur_state->has_constraint
+ || check_halt_state_context (mctx, cur_state,
+ re_string_cur_idx (&mctx->input)))
+ {
+ /* We found an appropriate halt state. */
+ match_last = re_string_cur_idx (&mctx->input);
+ match = 1;
+
+ /* We found a match, do not modify match_first below. */
+ p_match_first = NULL;
+ if (!fl_longest_match)
+ break;
+ }
+ }
+ }
+
+ if (p_match_first)
+ *p_match_first += next_start_idx;
+
+ return match_last;
+}
+
+/* Check NODE match the current context. */
+
+static int
+internal_function
+check_halt_node_context (const re_dfa_t *dfa, int node, unsigned int context)
+{
+ re_token_type_t type = dfa->nodes[node].type;
+ unsigned int constraint = dfa->nodes[node].constraint;
+ if (type != END_OF_RE)
+ return 0;
+ if (!constraint)
+ return 1;
+ if (NOT_SATISFY_NEXT_CONSTRAINT (constraint, context))
+ return 0;
+ return 1;
+}
+
+/* Check the halt state STATE match the current context.
+ Return 0 if not match, if the node, STATE has, is a halt node and
+ match the context, return the node. */
+
+static int
+internal_function
+check_halt_state_context (const re_match_context_t *mctx,
+ const re_dfastate_t *state, int idx)
+{
+ int i;
+ unsigned int context;
+#ifdef DEBUG
+ assert (state->halt);
+#endif
+ context = re_string_context_at (&mctx->input, idx, mctx->eflags);
+ for (i = 0; i < state->nodes.nelem; ++i)
+ if (check_halt_node_context (mctx->dfa, state->nodes.elems[i], context))
+ return state->nodes.elems[i];
+ return 0;
+}
+
+/* Compute the next node to which "NFA" transit from NODE("NFA" is a NFA
+ corresponding to the DFA).
+ Return the destination node, and update EPS_VIA_NODES, return -1 in case
+ of errors. */
+
+static int
+internal_function
+proceed_next_node (const re_match_context_t *mctx, int nregs, regmatch_t *regs,
+ int *pidx, int node, re_node_set *eps_via_nodes,
+ struct re_fail_stack_t *fs)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ int i, err;
+ if (IS_EPSILON_NODE (dfa->nodes[node].type))
+ {
+ re_node_set *cur_nodes = &mctx->state_log[*pidx]->nodes;
+ re_node_set *edests = &dfa->edests[node];
+ int dest_node;
+ err = re_node_set_insert (eps_via_nodes, node);
+ if (BE (err < 0, 0))
+ return -2;
+ /* Pick up a valid destination, or return -1 if none is found. */
+ for (dest_node = -1, i = 0; i < edests->nelem; ++i)
+ {
+ int candidate = edests->elems[i];
+ if (!re_node_set_contains (cur_nodes, candidate))
+ continue;
+ if (dest_node == -1)
+ dest_node = candidate;
+
+ else
+ {
+ /* In order to avoid infinite loop like "(a*)*", return the second
+ epsilon-transition if the first was already considered. */
+ if (re_node_set_contains (eps_via_nodes, dest_node))
+ return candidate;
+
+ /* Otherwise, push the second epsilon-transition on the fail stack. */
+ else if (fs != NULL
+ && push_fail_stack (fs, *pidx, candidate, nregs, regs,
+ eps_via_nodes))
+ return -2;
+
+ /* We know we are going to exit. */
+ break;
+ }
+ }
+ return dest_node;
+ }
+ else
+ {
+ int naccepted = 0;
+ re_token_type_t type = dfa->nodes[node].type;
+
+#ifdef RE_ENABLE_I18N
+ if (dfa->nodes[node].accept_mb)
+ naccepted = check_node_accept_bytes (dfa, node, &mctx->input, *pidx);
+ else
+#endif /* RE_ENABLE_I18N */
+ if (type == OP_BACK_REF)
+ {
+ int subexp_idx = dfa->nodes[node].opr.idx + 1;
+ naccepted = regs[subexp_idx].rm_eo - regs[subexp_idx].rm_so;
+ if (fs != NULL)
+ {
+ if (regs[subexp_idx].rm_so == -1 || regs[subexp_idx].rm_eo == -1)
+ return -1;
+ else if (naccepted)
+ {
+ char *buf = (char *) re_string_get_buffer (&mctx->input);
+ if (memcmp (buf + regs[subexp_idx].rm_so, buf + *pidx,
+ naccepted) != 0)
+ return -1;
+ }
+ }
+
+ if (naccepted == 0)
+ {
+ int dest_node;
+ err = re_node_set_insert (eps_via_nodes, node);
+ if (BE (err < 0, 0))
+ return -2;
+ dest_node = dfa->edests[node].elems[0];
+ if (re_node_set_contains (&mctx->state_log[*pidx]->nodes,
+ dest_node))
+ return dest_node;
+ }
+ }
+
+ if (naccepted != 0
+ || check_node_accept (mctx, dfa->nodes + node, *pidx))
+ {
+ int dest_node = dfa->nexts[node];
+ *pidx = (naccepted == 0) ? *pidx + 1 : *pidx + naccepted;
+ if (fs && (*pidx > mctx->match_last || mctx->state_log[*pidx] == NULL
+ || !re_node_set_contains (&mctx->state_log[*pidx]->nodes,
+ dest_node)))
+ return -1;
+ re_node_set_empty (eps_via_nodes);
+ return dest_node;
+ }
+ }
+ return -1;
+}
+
+static reg_errcode_t
+internal_function
+push_fail_stack (struct re_fail_stack_t *fs, int str_idx, int dest_node,
+ int nregs, regmatch_t *regs, re_node_set *eps_via_nodes)
+{
+ reg_errcode_t err;
+ int num = fs->num++;
+ if (fs->num == fs->alloc)
+ {
+ struct re_fail_stack_ent_t *new_array;
+ new_array = realloc (fs->stack, (sizeof (struct re_fail_stack_ent_t)
+ * fs->alloc * 2));
+ if (new_array == NULL)
+ return REG_ESPACE;
+ fs->alloc *= 2;
+ fs->stack = new_array;
+ }
+ fs->stack[num].idx = str_idx;
+ fs->stack[num].node = dest_node;
+ fs->stack[num].regs = re_malloc (regmatch_t, nregs);
+ if (fs->stack[num].regs == NULL)
+ return REG_ESPACE;
+ memcpy (fs->stack[num].regs, regs, sizeof (regmatch_t) * nregs);
+ err = re_node_set_init_copy (&fs->stack[num].eps_via_nodes, eps_via_nodes);
+ return err;
+}
+
+static int
+internal_function
+pop_fail_stack (struct re_fail_stack_t *fs, int *pidx, int nregs,
+ regmatch_t *regs, re_node_set *eps_via_nodes)
+{
+ int num = --fs->num;
+ assert (num >= 0);
+ *pidx = fs->stack[num].idx;
+ memcpy (regs, fs->stack[num].regs, sizeof (regmatch_t) * nregs);
+ re_node_set_free (eps_via_nodes);
+ re_free (fs->stack[num].regs);
+ *eps_via_nodes = fs->stack[num].eps_via_nodes;
+ return fs->stack[num].node;
+}
+
+/* Set the positions where the subexpressions are starts/ends to registers
+ PMATCH.
+ Note: We assume that pmatch[0] is already set, and
+ pmatch[i].rm_so == pmatch[i].rm_eo == -1 for 0 < i < nmatch. */
+
+static reg_errcode_t
+internal_function
+set_regs (const regex_t *preg, const re_match_context_t *mctx, size_t nmatch,
+ regmatch_t *pmatch, int fl_backtrack)
+{
+ const re_dfa_t *dfa = (const re_dfa_t *) preg->buffer;
+ int idx, cur_node;
+ re_node_set eps_via_nodes;
+ struct re_fail_stack_t *fs;
+ struct re_fail_stack_t fs_body = { 0, 2, NULL };
+ regmatch_t *prev_idx_match;
+ int prev_idx_match_malloced = 0;
+
+#ifdef DEBUG
+ assert (nmatch > 1);
+ assert (mctx->state_log != NULL);
+#endif
+ if (fl_backtrack)
+ {
+ fs = &fs_body;
+ fs->stack = re_malloc (struct re_fail_stack_ent_t, fs->alloc);
+ if (fs->stack == NULL)
+ return REG_ESPACE;
+ }
+ else
+ fs = NULL;
+
+ cur_node = dfa->init_node;
+ re_node_set_init_empty (&eps_via_nodes);
+
+#ifdef HAVE_ALLOCA
+ if (__libc_use_alloca (nmatch * sizeof (regmatch_t)))
+ prev_idx_match = (regmatch_t *) alloca (nmatch * sizeof (regmatch_t));
+ else
+#endif
+ {
+ prev_idx_match = re_malloc (regmatch_t, nmatch);
+ if (prev_idx_match == NULL)
+ {
+ free_fail_stack_return (fs);
+ return REG_ESPACE;
+ }
+ prev_idx_match_malloced = 1;
+ }
+ memcpy (prev_idx_match, pmatch, sizeof (regmatch_t) * nmatch);
+
+ for (idx = pmatch[0].rm_so; idx <= pmatch[0].rm_eo ;)
+ {
+ update_regs (dfa, pmatch, prev_idx_match, cur_node, idx, nmatch);
+
+ if (idx == pmatch[0].rm_eo && cur_node == mctx->last_node)
+ {
+ int reg_idx;
+ if (fs)
+ {
+ for (reg_idx = 0; reg_idx < nmatch; ++reg_idx)
+ if (pmatch[reg_idx].rm_so > -1 && pmatch[reg_idx].rm_eo == -1)
+ break;
+ if (reg_idx == nmatch)
+ {
+ re_node_set_free (&eps_via_nodes);
+ if (prev_idx_match_malloced)
+ re_free (prev_idx_match);
+ return free_fail_stack_return (fs);
+ }
+ cur_node = pop_fail_stack (fs, &idx, nmatch, pmatch,
+ &eps_via_nodes);
+ }
+ else
+ {
+ re_node_set_free (&eps_via_nodes);
+ if (prev_idx_match_malloced)
+ re_free (prev_idx_match);
+ return REG_NOERROR;
+ }
+ }
+
+ /* Proceed to next node. */
+ cur_node = proceed_next_node (mctx, nmatch, pmatch, &idx, cur_node,
+ &eps_via_nodes, fs);
+
+ if (BE (cur_node < 0, 0))
+ {
+ if (BE (cur_node == -2, 0))
+ {
+ re_node_set_free (&eps_via_nodes);
+ if (prev_idx_match_malloced)
+ re_free (prev_idx_match);
+ free_fail_stack_return (fs);
+ return REG_ESPACE;
+ }
+ if (fs)
+ cur_node = pop_fail_stack (fs, &idx, nmatch, pmatch,
+ &eps_via_nodes);
+ else
+ {
+ re_node_set_free (&eps_via_nodes);
+ if (prev_idx_match_malloced)
+ re_free (prev_idx_match);
+ return REG_NOMATCH;
+ }
+ }
+ }
+ re_node_set_free (&eps_via_nodes);
+ if (prev_idx_match_malloced)
+ re_free (prev_idx_match);
+ return free_fail_stack_return (fs);
+}
+
+static reg_errcode_t
+internal_function
+free_fail_stack_return (struct re_fail_stack_t *fs)
+{
+ if (fs)
+ {
+ int fs_idx;
+ for (fs_idx = 0; fs_idx < fs->num; ++fs_idx)
+ {
+ re_node_set_free (&fs->stack[fs_idx].eps_via_nodes);
+ re_free (fs->stack[fs_idx].regs);
+ }
+ re_free (fs->stack);
+ }
+ return REG_NOERROR;
+}
+
+static void
+internal_function
+update_regs (const re_dfa_t *dfa, regmatch_t *pmatch,
+ regmatch_t *prev_idx_match, int cur_node, int cur_idx, int nmatch)
+{
+ int type = dfa->nodes[cur_node].type;
+ if (type == OP_OPEN_SUBEXP)
+ {
+ int reg_num = dfa->nodes[cur_node].opr.idx + 1;
+
+ /* We are at the first node of this sub expression. */
+ if (reg_num < nmatch)
+ {
+ pmatch[reg_num].rm_so = cur_idx;
+ pmatch[reg_num].rm_eo = -1;
+ }
+ }
+ else if (type == OP_CLOSE_SUBEXP)
+ {
+ int reg_num = dfa->nodes[cur_node].opr.idx + 1;
+ if (reg_num < nmatch)
+ {
+ /* We are at the last node of this sub expression. */
+ if (pmatch[reg_num].rm_so < cur_idx)
+ {
+ pmatch[reg_num].rm_eo = cur_idx;
+ /* This is a non-empty match or we are not inside an optional
+ subexpression. Accept this right away. */
+ memcpy (prev_idx_match, pmatch, sizeof (regmatch_t) * nmatch);
+ }
+ else
+ {
+ if (dfa->nodes[cur_node].opt_subexp
+ && prev_idx_match[reg_num].rm_so != -1)
+ /* We transited through an empty match for an optional
+ subexpression, like (a?)*, and this is not the subexp's
+ first match. Copy back the old content of the registers
+ so that matches of an inner subexpression are undone as
+ well, like in ((a?))*. */
+ memcpy (pmatch, prev_idx_match, sizeof (regmatch_t) * nmatch);
+ else
+ /* We completed a subexpression, but it may be part of
+ an optional one, so do not update PREV_IDX_MATCH. */
+ pmatch[reg_num].rm_eo = cur_idx;
+ }
+ }
+ }
+}
+
+/* This function checks the STATE_LOG from the SCTX->last_str_idx to 0
+ and sift the nodes in each states according to the following rules.
+ Updated state_log will be wrote to STATE_LOG.
+
+ Rules: We throw away the Node `a' in the STATE_LOG[STR_IDX] if...
+ 1. When STR_IDX == MATCH_LAST(the last index in the state_log):
+ If `a' isn't the LAST_NODE and `a' can't epsilon transit to
+ the LAST_NODE, we throw away the node `a'.
+ 2. When 0 <= STR_IDX < MATCH_LAST and `a' accepts
+ string `s' and transit to `b':
+ i. If 'b' isn't in the STATE_LOG[STR_IDX+strlen('s')], we throw
+ away the node `a'.
+ ii. If 'b' is in the STATE_LOG[STR_IDX+strlen('s')] but 'b' is
+ thrown away, we throw away the node `a'.
+ 3. When 0 <= STR_IDX < MATCH_LAST and 'a' epsilon transit to 'b':
+ i. If 'b' isn't in the STATE_LOG[STR_IDX], we throw away the
+ node `a'.
+ ii. If 'b' is in the STATE_LOG[STR_IDX] but 'b' is thrown away,
+ we throw away the node `a'. */
+
+#define STATE_NODE_CONTAINS(state,node) \
+ ((state) != NULL && re_node_set_contains (&(state)->nodes, node))
+
+static reg_errcode_t
+internal_function
+sift_states_backward (const re_match_context_t *mctx, re_sift_context_t *sctx)
+{
+ reg_errcode_t err;
+ int null_cnt = 0;
+ int str_idx = sctx->last_str_idx;
+ re_node_set cur_dest;
+
+#ifdef DEBUG
+ assert (mctx->state_log != NULL && mctx->state_log[str_idx] != NULL);
+#endif
+
+ /* Build sifted state_log[str_idx]. It has the nodes which can epsilon
+ transit to the last_node and the last_node itself. */
+ err = re_node_set_init_1 (&cur_dest, sctx->last_node);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ err = update_cur_sifted_state (mctx, sctx, str_idx, &cur_dest);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+
+ /* Then check each states in the state_log. */
+ while (str_idx > 0)
+ {
+ /* Update counters. */
+ null_cnt = (sctx->sifted_states[str_idx] == NULL) ? null_cnt + 1 : 0;
+ if (null_cnt > mctx->max_mb_elem_len)
+ {
+ memset (sctx->sifted_states, '\0',
+ sizeof (re_dfastate_t *) * str_idx);
+ re_node_set_free (&cur_dest);
+ return REG_NOERROR;
+ }
+ re_node_set_empty (&cur_dest);
+ --str_idx;
+
+ if (mctx->state_log[str_idx])
+ {
+ err = build_sifted_states (mctx, sctx, str_idx, &cur_dest);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+ }
+
+ /* Add all the nodes which satisfy the following conditions:
+ - It can epsilon transit to a node in CUR_DEST.
+ - It is in CUR_SRC.
+ And update state_log. */
+ err = update_cur_sifted_state (mctx, sctx, str_idx, &cur_dest);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+ }
+ err = REG_NOERROR;
+ free_return:
+ re_node_set_free (&cur_dest);
+ return err;
+}
+
+static reg_errcode_t
+internal_function
+build_sifted_states (const re_match_context_t *mctx, re_sift_context_t *sctx,
+ int str_idx, re_node_set *cur_dest)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ const re_node_set *cur_src = &mctx->state_log[str_idx]->non_eps_nodes;
+ int i;
+
+ /* Then build the next sifted state.
+ We build the next sifted state on `cur_dest', and update
+ `sifted_states[str_idx]' with `cur_dest'.
+ Note:
+ `cur_dest' is the sifted state from `state_log[str_idx + 1]'.
+ `cur_src' points the node_set of the old `state_log[str_idx]'
+ (with the epsilon nodes pre-filtered out). */
+ for (i = 0; i < cur_src->nelem; i++)
+ {
+ int prev_node = cur_src->elems[i];
+ int naccepted = 0;
+ int ret;
+
+#ifdef DEBUG
+ re_token_type_t type = dfa->nodes[prev_node].type;
+ assert (!IS_EPSILON_NODE (type));
+#endif
+#ifdef RE_ENABLE_I18N
+ /* If the node may accept `multi byte'. */
+ if (dfa->nodes[prev_node].accept_mb)
+ naccepted = sift_states_iter_mb (mctx, sctx, prev_node,
+ str_idx, sctx->last_str_idx);
+#endif /* RE_ENABLE_I18N */
+
+ /* We don't check backreferences here.
+ See update_cur_sifted_state(). */
+ if (!naccepted
+ && check_node_accept (mctx, dfa->nodes + prev_node, str_idx)
+ && STATE_NODE_CONTAINS (sctx->sifted_states[str_idx + 1],
+ dfa->nexts[prev_node]))
+ naccepted = 1;
+
+ if (naccepted == 0)
+ continue;
+
+ if (sctx->limits.nelem)
+ {
+ int to_idx = str_idx + naccepted;
+ if (check_dst_limits (mctx, &sctx->limits,
+ dfa->nexts[prev_node], to_idx,
+ prev_node, str_idx))
+ continue;
+ }
+ ret = re_node_set_insert (cur_dest, prev_node);
+ if (BE (ret == -1, 0))
+ return REG_ESPACE;
+ }
+
+ return REG_NOERROR;
+}
+
+/* Helper functions. */
+
+static reg_errcode_t
+internal_function
+clean_state_log_if_needed (re_match_context_t *mctx, int next_state_log_idx)
+{
+ int top = mctx->state_log_top;
+
+ if (next_state_log_idx >= mctx->input.bufs_len
+ || (next_state_log_idx >= mctx->input.valid_len
+ && mctx->input.valid_len < mctx->input.len))
+ {
+ reg_errcode_t err;
+ err = extend_buffers (mctx);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+
+ if (top < next_state_log_idx)
+ {
+ memset (mctx->state_log + top + 1, '\0',
+ sizeof (re_dfastate_t *) * (next_state_log_idx - top));
+ mctx->state_log_top = next_state_log_idx;
+ }
+ return REG_NOERROR;
+}
+
+static reg_errcode_t
+internal_function
+merge_state_array (const re_dfa_t *dfa, re_dfastate_t **dst,
+ re_dfastate_t **src, int num)
+{
+ int st_idx;
+ reg_errcode_t err;
+ for (st_idx = 0; st_idx < num; ++st_idx)
+ {
+ if (dst[st_idx] == NULL)
+ dst[st_idx] = src[st_idx];
+ else if (src[st_idx] != NULL)
+ {
+ re_node_set merged_set;
+ err = re_node_set_init_union (&merged_set, &dst[st_idx]->nodes,
+ &src[st_idx]->nodes);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ dst[st_idx] = re_acquire_state (&err, dfa, &merged_set);
+ re_node_set_free (&merged_set);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+ }
+ return REG_NOERROR;
+}
+
+static reg_errcode_t
+internal_function
+update_cur_sifted_state (const re_match_context_t *mctx,
+ re_sift_context_t *sctx, int str_idx,
+ re_node_set *dest_nodes)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ reg_errcode_t err = REG_NOERROR;
+ const re_node_set *candidates;
+ candidates = ((mctx->state_log[str_idx] == NULL) ? NULL
+ : &mctx->state_log[str_idx]->nodes);
+
+ if (dest_nodes->nelem == 0)
+ sctx->sifted_states[str_idx] = NULL;
+ else
+ {
+ if (candidates)
+ {
+ /* At first, add the nodes which can epsilon transit to a node in
+ DEST_NODE. */
+ err = add_epsilon_src_nodes (dfa, dest_nodes, candidates);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+
+ /* Then, check the limitations in the current sift_context. */
+ if (sctx->limits.nelem)
+ {
+ err = check_subexp_limits (dfa, dest_nodes, candidates, &sctx->limits,
+ mctx->bkref_ents, str_idx);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+ }
+
+ sctx->sifted_states[str_idx] = re_acquire_state (&err, dfa, dest_nodes);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+
+ if (candidates && mctx->state_log[str_idx]->has_backref)
+ {
+ err = sift_states_bkref (mctx, sctx, str_idx, candidates);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+ return REG_NOERROR;
+}
+
+static reg_errcode_t
+internal_function
+add_epsilon_src_nodes (const re_dfa_t *dfa, re_node_set *dest_nodes,
+ const re_node_set *candidates)
+{
+ reg_errcode_t err = REG_NOERROR;
+ int i;
+
+ re_dfastate_t *state = re_acquire_state (&err, dfa, dest_nodes);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+
+ if (!state->inveclosure.alloc)
+ {
+ err = re_node_set_alloc (&state->inveclosure, dest_nodes->nelem);
+ if (BE (err != REG_NOERROR, 0))
+ return REG_ESPACE;
+ for (i = 0; i < dest_nodes->nelem; i++)
+ {
+ err = re_node_set_merge (&state->inveclosure,
+ dfa->inveclosures + dest_nodes->elems[i]);
+ if (BE (err != REG_NOERROR, 0))
+ return REG_ESPACE;
+ }
+ }
+ return re_node_set_add_intersect (dest_nodes, candidates,
+ &state->inveclosure);
+}
+
+static reg_errcode_t
+internal_function
+sub_epsilon_src_nodes (const re_dfa_t *dfa, int node, re_node_set *dest_nodes,
+ const re_node_set *candidates)
+{
+ int ecl_idx;
+ reg_errcode_t err;
+ re_node_set *inv_eclosure = dfa->inveclosures + node;
+ re_node_set except_nodes;
+ re_node_set_init_empty (&except_nodes);
+ for (ecl_idx = 0; ecl_idx < inv_eclosure->nelem; ++ecl_idx)
+ {
+ int cur_node = inv_eclosure->elems[ecl_idx];
+ if (cur_node == node)
+ continue;
+ if (IS_EPSILON_NODE (dfa->nodes[cur_node].type))
+ {
+ int edst1 = dfa->edests[cur_node].elems[0];
+ int edst2 = ((dfa->edests[cur_node].nelem > 1)
+ ? dfa->edests[cur_node].elems[1] : -1);
+ if ((!re_node_set_contains (inv_eclosure, edst1)
+ && re_node_set_contains (dest_nodes, edst1))
+ || (edst2 > 0
+ && !re_node_set_contains (inv_eclosure, edst2)
+ && re_node_set_contains (dest_nodes, edst2)))
+ {
+ err = re_node_set_add_intersect (&except_nodes, candidates,
+ dfa->inveclosures + cur_node);
+ if (BE (err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&except_nodes);
+ return err;
+ }
+ }
+ }
+ }
+ for (ecl_idx = 0; ecl_idx < inv_eclosure->nelem; ++ecl_idx)
+ {
+ int cur_node = inv_eclosure->elems[ecl_idx];
+ if (!re_node_set_contains (&except_nodes, cur_node))
+ {
+ int idx = re_node_set_contains (dest_nodes, cur_node) - 1;
+ re_node_set_remove_at (dest_nodes, idx);
+ }
+ }
+ re_node_set_free (&except_nodes);
+ return REG_NOERROR;
+}
+
+static int
+internal_function
+check_dst_limits (const re_match_context_t *mctx, re_node_set *limits,
+ int dst_node, int dst_idx, int src_node, int src_idx)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ int lim_idx, src_pos, dst_pos;
+
+ int dst_bkref_idx = search_cur_bkref_entry (mctx, dst_idx);
+ int src_bkref_idx = search_cur_bkref_entry (mctx, src_idx);
+ for (lim_idx = 0; lim_idx < limits->nelem; ++lim_idx)
+ {
+ int subexp_idx;
+ struct re_backref_cache_entry *ent;
+ ent = mctx->bkref_ents + limits->elems[lim_idx];
+ subexp_idx = dfa->nodes[ent->node].opr.idx;
+
+ dst_pos = check_dst_limits_calc_pos (mctx, limits->elems[lim_idx],
+ subexp_idx, dst_node, dst_idx,
+ dst_bkref_idx);
+ src_pos = check_dst_limits_calc_pos (mctx, limits->elems[lim_idx],
+ subexp_idx, src_node, src_idx,
+ src_bkref_idx);
+
+ /* In case of:
+ <src> <dst> ( <subexp> )
+ ( <subexp> ) <src> <dst>
+ ( <subexp1> <src> <subexp2> <dst> <subexp3> ) */
+ if (src_pos == dst_pos)
+ continue; /* This is unrelated limitation. */
+ else
+ return 1;
+ }
+ return 0;
+}
+
+static int
+internal_function
+check_dst_limits_calc_pos_1 (const re_match_context_t *mctx, int boundaries,
+ int subexp_idx, int from_node, int bkref_idx)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ const re_node_set *eclosures = dfa->eclosures + from_node;
+ int node_idx;
+
+ /* Else, we are on the boundary: examine the nodes on the epsilon
+ closure. */
+ for (node_idx = 0; node_idx < eclosures->nelem; ++node_idx)
+ {
+ int node = eclosures->elems[node_idx];
+ switch (dfa->nodes[node].type)
+ {
+ case OP_BACK_REF:
+ if (bkref_idx != -1)
+ {
+ struct re_backref_cache_entry *ent = mctx->bkref_ents + bkref_idx;
+ do
+ {
+ int dst, cpos;
+
+ if (ent->node != node)
+ continue;
+
+ if (subexp_idx < BITSET_WORD_BITS
+ && !(ent->eps_reachable_subexps_map
+ & ((bitset_word_t) 1 << subexp_idx)))
+ continue;
+
+ /* Recurse trying to reach the OP_OPEN_SUBEXP and
+ OP_CLOSE_SUBEXP cases below. But, if the
+ destination node is the same node as the source
+ node, don't recurse because it would cause an
+ infinite loop: a regex that exhibits this behavior
+ is ()\1*\1* */
+ dst = dfa->edests[node].elems[0];
+ if (dst == from_node)
+ {
+ if (boundaries & 1)
+ return -1;
+ else /* if (boundaries & 2) */
+ return 0;
+ }
+
+ cpos =
+ check_dst_limits_calc_pos_1 (mctx, boundaries, subexp_idx,
+ dst, bkref_idx);
+ if (cpos == -1 /* && (boundaries & 1) */)
+ return -1;
+ if (cpos == 0 && (boundaries & 2))
+ return 0;
+
+ if (subexp_idx < BITSET_WORD_BITS)
+ ent->eps_reachable_subexps_map
+ &= ~((bitset_word_t) 1 << subexp_idx);
+ }
+ while (ent++->more);
+ }
+ break;
+
+ case OP_OPEN_SUBEXP:
+ if ((boundaries & 1) && subexp_idx == dfa->nodes[node].opr.idx)
+ return -1;
+ break;
+
+ case OP_CLOSE_SUBEXP:
+ if ((boundaries & 2) && subexp_idx == dfa->nodes[node].opr.idx)
+ return 0;
+ break;
+
+ default:
+ break;
+ }
+ }
+
+ return (boundaries & 2) ? 1 : 0;
+}
+
+static int
+internal_function
+check_dst_limits_calc_pos (const re_match_context_t *mctx, int limit,
+ int subexp_idx, int from_node, int str_idx,
+ int bkref_idx)
+{
+ struct re_backref_cache_entry *lim = mctx->bkref_ents + limit;
+ int boundaries;
+
+ /* If we are outside the range of the subexpression, return -1 or 1. */
+ if (str_idx < lim->subexp_from)
+ return -1;
+
+ if (lim->subexp_to < str_idx)
+ return 1;
+
+ /* If we are within the subexpression, return 0. */
+ boundaries = (str_idx == lim->subexp_from);
+ boundaries |= (str_idx == lim->subexp_to) << 1;
+ if (boundaries == 0)
+ return 0;
+
+ /* Else, examine epsilon closure. */
+ return check_dst_limits_calc_pos_1 (mctx, boundaries, subexp_idx,
+ from_node, bkref_idx);
+}
+
+/* Check the limitations of sub expressions LIMITS, and remove the nodes
+ which are against limitations from DEST_NODES. */
+
+static reg_errcode_t
+internal_function
+check_subexp_limits (const re_dfa_t *dfa, re_node_set *dest_nodes,
+ const re_node_set *candidates, re_node_set *limits,
+ struct re_backref_cache_entry *bkref_ents, int str_idx)
+{
+ reg_errcode_t err;
+ int node_idx, lim_idx;
+
+ for (lim_idx = 0; lim_idx < limits->nelem; ++lim_idx)
+ {
+ int subexp_idx;
+ struct re_backref_cache_entry *ent;
+ ent = bkref_ents + limits->elems[lim_idx];
+
+ if (str_idx <= ent->subexp_from || ent->str_idx < str_idx)
+ continue; /* This is unrelated limitation. */
+
+ subexp_idx = dfa->nodes[ent->node].opr.idx;
+ if (ent->subexp_to == str_idx)
+ {
+ int ops_node = -1;
+ int cls_node = -1;
+ for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx)
+ {
+ int node = dest_nodes->elems[node_idx];
+ re_token_type_t type = dfa->nodes[node].type;
+ if (type == OP_OPEN_SUBEXP
+ && subexp_idx == dfa->nodes[node].opr.idx)
+ ops_node = node;
+ else if (type == OP_CLOSE_SUBEXP
+ && subexp_idx == dfa->nodes[node].opr.idx)
+ cls_node = node;
+ }
+
+ /* Check the limitation of the open subexpression. */
+ /* Note that (ent->subexp_to = str_idx != ent->subexp_from). */
+ if (ops_node >= 0)
+ {
+ err = sub_epsilon_src_nodes (dfa, ops_node, dest_nodes,
+ candidates);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+
+ /* Check the limitation of the close subexpression. */
+ if (cls_node >= 0)
+ for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx)
+ {
+ int node = dest_nodes->elems[node_idx];
+ if (!re_node_set_contains (dfa->inveclosures + node,
+ cls_node)
+ && !re_node_set_contains (dfa->eclosures + node,
+ cls_node))
+ {
+ /* It is against this limitation.
+ Remove it form the current sifted state. */
+ err = sub_epsilon_src_nodes (dfa, node, dest_nodes,
+ candidates);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ --node_idx;
+ }
+ }
+ }
+ else /* (ent->subexp_to != str_idx) */
+ {
+ for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx)
+ {
+ int node = dest_nodes->elems[node_idx];
+ re_token_type_t type = dfa->nodes[node].type;
+ if (type == OP_CLOSE_SUBEXP || type == OP_OPEN_SUBEXP)
+ {
+ if (subexp_idx != dfa->nodes[node].opr.idx)
+ continue;
+ /* It is against this limitation.
+ Remove it form the current sifted state. */
+ err = sub_epsilon_src_nodes (dfa, node, dest_nodes,
+ candidates);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+ }
+ }
+ }
+ return REG_NOERROR;
+}
+
+static reg_errcode_t
+internal_function
+sift_states_bkref (const re_match_context_t *mctx, re_sift_context_t *sctx,
+ int str_idx, const re_node_set *candidates)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ reg_errcode_t err;
+ int node_idx, node;
+ re_sift_context_t local_sctx;
+ int first_idx = search_cur_bkref_entry (mctx, str_idx);
+
+ if (first_idx == -1)
+ return REG_NOERROR;
+
+ local_sctx.sifted_states = NULL; /* Mark that it hasn't been initialized. */
+
+ for (node_idx = 0; node_idx < candidates->nelem; ++node_idx)
+ {
+ int enabled_idx;
+ re_token_type_t type;
+ struct re_backref_cache_entry *entry;
+ node = candidates->elems[node_idx];
+ type = dfa->nodes[node].type;
+ /* Avoid infinite loop for the REs like "()\1+". */
+ if (node == sctx->last_node && str_idx == sctx->last_str_idx)
+ continue;
+ if (type != OP_BACK_REF)
+ continue;
+
+ entry = mctx->bkref_ents + first_idx;
+ enabled_idx = first_idx;
+ do
+ {
+ int subexp_len;
+ int to_idx;
+ int dst_node;
+ int ret;
+ re_dfastate_t *cur_state;
+
+ if (entry->node != node)
+ continue;
+ subexp_len = entry->subexp_to - entry->subexp_from;
+ to_idx = str_idx + subexp_len;
+ dst_node = (subexp_len ? dfa->nexts[node]
+ : dfa->edests[node].elems[0]);
+
+ if (to_idx > sctx->last_str_idx
+ || sctx->sifted_states[to_idx] == NULL
+ || !STATE_NODE_CONTAINS (sctx->sifted_states[to_idx], dst_node)
+ || check_dst_limits (mctx, &sctx->limits, node,
+ str_idx, dst_node, to_idx))
+ continue;
+
+ if (local_sctx.sifted_states == NULL)
+ {
+ local_sctx = *sctx;
+ err = re_node_set_init_copy (&local_sctx.limits, &sctx->limits);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+ }
+ local_sctx.last_node = node;
+ local_sctx.last_str_idx = str_idx;
+ ret = re_node_set_insert (&local_sctx.limits, enabled_idx);
+ if (BE (ret < 0, 0))
+ {
+ err = REG_ESPACE;
+ goto free_return;
+ }
+ cur_state = local_sctx.sifted_states[str_idx];
+ err = sift_states_backward (mctx, &local_sctx);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+ if (sctx->limited_states != NULL)
+ {
+ err = merge_state_array (dfa, sctx->limited_states,
+ local_sctx.sifted_states,
+ str_idx + 1);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+ }
+ local_sctx.sifted_states[str_idx] = cur_state;
+ re_node_set_remove (&local_sctx.limits, enabled_idx);
+
+ /* mctx->bkref_ents may have changed, reload the pointer. */
+ entry = mctx->bkref_ents + enabled_idx;
+ }
+ while (enabled_idx++, entry++->more);
+ }
+ err = REG_NOERROR;
+ free_return:
+ if (local_sctx.sifted_states != NULL)
+ {
+ re_node_set_free (&local_sctx.limits);
+ }
+
+ return err;
+}
+
+
+#ifdef RE_ENABLE_I18N
+static int
+internal_function
+sift_states_iter_mb (const re_match_context_t *mctx, re_sift_context_t *sctx,
+ int node_idx, int str_idx, int max_str_idx)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ int naccepted;
+ /* Check the node can accept `multi byte'. */
+ naccepted = check_node_accept_bytes (dfa, node_idx, &mctx->input, str_idx);
+ if (naccepted > 0 && str_idx + naccepted <= max_str_idx &&
+ !STATE_NODE_CONTAINS (sctx->sifted_states[str_idx + naccepted],
+ dfa->nexts[node_idx]))
+ /* The node can't accept the `multi byte', or the
+ destination was already thrown away, then the node
+ could't accept the current input `multi byte'. */
+ naccepted = 0;
+ /* Otherwise, it is sure that the node could accept
+ `naccepted' bytes input. */
+ return naccepted;
+}
+#endif /* RE_ENABLE_I18N */
+
+
+/* Functions for state transition. */
+
+/* Return the next state to which the current state STATE will transit by
+ accepting the current input byte, and update STATE_LOG if necessary.
+ If STATE can accept a multibyte char/collating element/back reference
+ update the destination of STATE_LOG. */
+
+static re_dfastate_t *
+internal_function
+transit_state (reg_errcode_t *err, re_match_context_t *mctx,
+ re_dfastate_t *state)
+{
+ re_dfastate_t **trtable;
+ unsigned char ch;
+
+#ifdef RE_ENABLE_I18N
+ /* If the current state can accept multibyte. */
+ if (BE (state->accept_mb, 0))
+ {
+ *err = transit_state_mb (mctx, state);
+ if (BE (*err != REG_NOERROR, 0))
+ return NULL;
+ }
+#endif /* RE_ENABLE_I18N */
+
+ /* Then decide the next state with the single byte. */
+#if 0
+ if (0)
+ /* don't use transition table */
+ return transit_state_sb (err, mctx, state);
+#endif
+
+ /* Use transition table */
+ ch = re_string_fetch_byte (&mctx->input);
+ for (;;)
+ {
+ trtable = state->trtable;
+ if (BE (trtable != NULL, 1))
+ return trtable[ch];
+
+ trtable = state->word_trtable;
+ if (BE (trtable != NULL, 1))
+ {
+ unsigned int context;
+ context
+ = re_string_context_at (&mctx->input,
+ re_string_cur_idx (&mctx->input) - 1,
+ mctx->eflags);
+ if (IS_WORD_CONTEXT (context))
+ return trtable[ch + SBC_MAX];
+ else
+ return trtable[ch];
+ }
+
+ if (!build_trtable (mctx->dfa, state))
+ {
+ *err = REG_ESPACE;
+ return NULL;
+ }
+
+ /* Retry, we now have a transition table. */
+ }
+}
+
+/* Update the state_log if we need */
+re_dfastate_t *
+internal_function
+merge_state_with_log (reg_errcode_t *err, re_match_context_t *mctx,
+ re_dfastate_t *next_state)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ int cur_idx = re_string_cur_idx (&mctx->input);
+
+ if (cur_idx > mctx->state_log_top)
+ {
+ mctx->state_log[cur_idx] = next_state;
+ mctx->state_log_top = cur_idx;
+ }
+ else if (mctx->state_log[cur_idx] == 0)
+ {
+ mctx->state_log[cur_idx] = next_state;
+ }
+ else
+ {
+ re_dfastate_t *pstate;
+ unsigned int context;
+ re_node_set next_nodes, *log_nodes, *table_nodes = NULL;
+ /* If (state_log[cur_idx] != 0), it implies that cur_idx is
+ the destination of a multibyte char/collating element/
+ back reference. Then the next state is the union set of
+ these destinations and the results of the transition table. */
+ pstate = mctx->state_log[cur_idx];
+ log_nodes = pstate->entrance_nodes;
+ if (next_state != NULL)
+ {
+ table_nodes = next_state->entrance_nodes;
+ *err = re_node_set_init_union (&next_nodes, table_nodes,
+ log_nodes);
+ if (BE (*err != REG_NOERROR, 0))
+ return NULL;
+ }
+ else
+ next_nodes = *log_nodes;
+ /* Note: We already add the nodes of the initial state,
+ then we don't need to add them here. */
+
+ context = re_string_context_at (&mctx->input,
+ re_string_cur_idx (&mctx->input) - 1,
+ mctx->eflags);
+ next_state = mctx->state_log[cur_idx]
+ = re_acquire_state_context (err, dfa, &next_nodes, context);
+ /* We don't need to check errors here, since the return value of
+ this function is next_state and ERR is already set. */
+
+ if (table_nodes != NULL)
+ re_node_set_free (&next_nodes);
+ }
+
+ if (BE (dfa->nbackref, 0) && next_state != NULL)
+ {
+ /* Check OP_OPEN_SUBEXP in the current state in case that we use them
+ later. We must check them here, since the back references in the
+ next state might use them. */
+ *err = check_subexp_matching_top (mctx, &next_state->nodes,
+ cur_idx);
+ if (BE (*err != REG_NOERROR, 0))
+ return NULL;
+
+ /* If the next state has back references. */
+ if (next_state->has_backref)
+ {
+ *err = transit_state_bkref (mctx, &next_state->nodes);
+ if (BE (*err != REG_NOERROR, 0))
+ return NULL;
+ next_state = mctx->state_log[cur_idx];
+ }
+ }
+
+ return next_state;
+}
+
+/* Skip bytes in the input that correspond to part of a
+ multi-byte match, then look in the log for a state
+ from which to restart matching. */
+re_dfastate_t *
+internal_function
+find_recover_state (reg_errcode_t *err, re_match_context_t *mctx)
+{
+ re_dfastate_t *cur_state;
+ do
+ {
+ int max = mctx->state_log_top;
+ int cur_str_idx = re_string_cur_idx (&mctx->input);
+
+ do
+ {
+ if (++cur_str_idx > max)
+ return NULL;
+ re_string_skip_bytes (&mctx->input, 1);
+ }
+ while (mctx->state_log[cur_str_idx] == NULL);
+
+ cur_state = merge_state_with_log (err, mctx, NULL);
+ }
+ while (*err == REG_NOERROR && cur_state == NULL);
+ return cur_state;
+}
+
+/* Helper functions for transit_state. */
+
+/* From the node set CUR_NODES, pick up the nodes whose types are
+ OP_OPEN_SUBEXP and which have corresponding back references in the regular
+ expression. And register them to use them later for evaluating the
+ correspoding back references. */
+
+static reg_errcode_t
+internal_function
+check_subexp_matching_top (re_match_context_t *mctx, re_node_set *cur_nodes,
+ int str_idx)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ int node_idx;
+ reg_errcode_t err;
+
+ /* TODO: This isn't efficient.
+ Because there might be more than one nodes whose types are
+ OP_OPEN_SUBEXP and whose index is SUBEXP_IDX, we must check all
+ nodes.
+ E.g. RE: (a){2} */
+ for (node_idx = 0; node_idx < cur_nodes->nelem; ++node_idx)
+ {
+ int node = cur_nodes->elems[node_idx];
+ if (dfa->nodes[node].type == OP_OPEN_SUBEXP
+ && dfa->nodes[node].opr.idx < BITSET_WORD_BITS
+ && (dfa->used_bkref_map
+ & ((bitset_word_t) 1 << dfa->nodes[node].opr.idx)))
+ {
+ err = match_ctx_add_subtop (mctx, node, str_idx);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+ }
+ return REG_NOERROR;
+}
+
+#if 0
+/* Return the next state to which the current state STATE will transit by
+ accepting the current input byte. */
+
+static re_dfastate_t *
+transit_state_sb (reg_errcode_t *err, re_match_context_t *mctx,
+ re_dfastate_t *state)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ re_node_set next_nodes;
+ re_dfastate_t *next_state;
+ int node_cnt, cur_str_idx = re_string_cur_idx (&mctx->input);
+ unsigned int context;
+
+ *err = re_node_set_alloc (&next_nodes, state->nodes.nelem + 1);
+ if (BE (*err != REG_NOERROR, 0))
+ return NULL;
+ for (node_cnt = 0; node_cnt < state->nodes.nelem; ++node_cnt)
+ {
+ int cur_node = state->nodes.elems[node_cnt];
+ if (check_node_accept (mctx, dfa->nodes + cur_node, cur_str_idx))
+ {
+ *err = re_node_set_merge (&next_nodes,
+ dfa->eclosures + dfa->nexts[cur_node]);
+ if (BE (*err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&next_nodes);
+ return NULL;
+ }
+ }
+ }
+ context = re_string_context_at (&mctx->input, cur_str_idx, mctx->eflags);
+ next_state = re_acquire_state_context (err, dfa, &next_nodes, context);
+ /* We don't need to check errors here, since the return value of
+ this function is next_state and ERR is already set. */
+
+ re_node_set_free (&next_nodes);
+ re_string_skip_bytes (&mctx->input, 1);
+ return next_state;
+}
+#endif
+
+#ifdef RE_ENABLE_I18N
+static reg_errcode_t
+internal_function
+transit_state_mb (re_match_context_t *mctx, re_dfastate_t *pstate)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ reg_errcode_t err;
+ int i;
+
+ for (i = 0; i < pstate->nodes.nelem; ++i)
+ {
+ re_node_set dest_nodes, *new_nodes;
+ int cur_node_idx = pstate->nodes.elems[i];
+ int naccepted, dest_idx;
+ unsigned int context;
+ re_dfastate_t *dest_state;
+
+ if (!dfa->nodes[cur_node_idx].accept_mb)
+ continue;
+
+ if (dfa->nodes[cur_node_idx].constraint)
+ {
+ context = re_string_context_at (&mctx->input,
+ re_string_cur_idx (&mctx->input),
+ mctx->eflags);
+ if (NOT_SATISFY_NEXT_CONSTRAINT (dfa->nodes[cur_node_idx].constraint,
+ context))
+ continue;
+ }
+
+ /* How many bytes the node can accept? */
+ naccepted = check_node_accept_bytes (dfa, cur_node_idx, &mctx->input,
+ re_string_cur_idx (&mctx->input));
+ if (naccepted == 0)
+ continue;
+
+ /* The node can accepts `naccepted' bytes. */
+ dest_idx = re_string_cur_idx (&mctx->input) + naccepted;
+ mctx->max_mb_elem_len = ((mctx->max_mb_elem_len < naccepted) ? naccepted
+ : mctx->max_mb_elem_len);
+ err = clean_state_log_if_needed (mctx, dest_idx);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+#ifdef DEBUG
+ assert (dfa->nexts[cur_node_idx] != -1);
+#endif
+ new_nodes = dfa->eclosures + dfa->nexts[cur_node_idx];
+
+ dest_state = mctx->state_log[dest_idx];
+ if (dest_state == NULL)
+ dest_nodes = *new_nodes;
+ else
+ {
+ err = re_node_set_init_union (&dest_nodes,
+ dest_state->entrance_nodes, new_nodes);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+ context = re_string_context_at (&mctx->input, dest_idx - 1,
+ mctx->eflags);
+ mctx->state_log[dest_idx]
+ = re_acquire_state_context (&err, dfa, &dest_nodes, context);
+ if (dest_state != NULL)
+ re_node_set_free (&dest_nodes);
+ if (BE (mctx->state_log[dest_idx] == NULL && err != REG_NOERROR, 0))
+ return err;
+ }
+ return REG_NOERROR;
+}
+#endif /* RE_ENABLE_I18N */
+
+static reg_errcode_t
+internal_function
+transit_state_bkref (re_match_context_t *mctx, const re_node_set *nodes)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ reg_errcode_t err;
+ int i;
+ int cur_str_idx = re_string_cur_idx (&mctx->input);
+
+ for (i = 0; i < nodes->nelem; ++i)
+ {
+ int dest_str_idx, prev_nelem, bkc_idx;
+ int node_idx = nodes->elems[i];
+ unsigned int context;
+ const re_token_t *node = dfa->nodes + node_idx;
+ re_node_set *new_dest_nodes;
+
+ /* Check whether `node' is a backreference or not. */
+ if (node->type != OP_BACK_REF)
+ continue;
+
+ if (node->constraint)
+ {
+ context = re_string_context_at (&mctx->input, cur_str_idx,
+ mctx->eflags);
+ if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context))
+ continue;
+ }
+
+ /* `node' is a backreference.
+ Check the substring which the substring matched. */
+ bkc_idx = mctx->nbkref_ents;
+ err = get_subexp (mctx, node_idx, cur_str_idx);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+
+ /* And add the epsilon closures (which is `new_dest_nodes') of
+ the backreference to appropriate state_log. */
+#ifdef DEBUG
+ assert (dfa->nexts[node_idx] != -1);
+#endif
+ for (; bkc_idx < mctx->nbkref_ents; ++bkc_idx)
+ {
+ int subexp_len;
+ re_dfastate_t *dest_state;
+ struct re_backref_cache_entry *bkref_ent;
+ bkref_ent = mctx->bkref_ents + bkc_idx;
+ if (bkref_ent->node != node_idx || bkref_ent->str_idx != cur_str_idx)
+ continue;
+ subexp_len = bkref_ent->subexp_to - bkref_ent->subexp_from;
+ new_dest_nodes = (subexp_len == 0
+ ? dfa->eclosures + dfa->edests[node_idx].elems[0]
+ : dfa->eclosures + dfa->nexts[node_idx]);
+ dest_str_idx = (cur_str_idx + bkref_ent->subexp_to
+ - bkref_ent->subexp_from);
+ context = re_string_context_at (&mctx->input, dest_str_idx - 1,
+ mctx->eflags);
+ dest_state = mctx->state_log[dest_str_idx];
+ prev_nelem = ((mctx->state_log[cur_str_idx] == NULL) ? 0
+ : mctx->state_log[cur_str_idx]->nodes.nelem);
+ /* Add `new_dest_node' to state_log. */
+ if (dest_state == NULL)
+ {
+ mctx->state_log[dest_str_idx]
+ = re_acquire_state_context (&err, dfa, new_dest_nodes,
+ context);
+ if (BE (mctx->state_log[dest_str_idx] == NULL
+ && err != REG_NOERROR, 0))
+ goto free_return;
+ }
+ else
+ {
+ re_node_set dest_nodes;
+ err = re_node_set_init_union (&dest_nodes,
+ dest_state->entrance_nodes,
+ new_dest_nodes);
+ if (BE (err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&dest_nodes);
+ goto free_return;
+ }
+ mctx->state_log[dest_str_idx]
+ = re_acquire_state_context (&err, dfa, &dest_nodes, context);
+ re_node_set_free (&dest_nodes);
+ if (BE (mctx->state_log[dest_str_idx] == NULL
+ && err != REG_NOERROR, 0))
+ goto free_return;
+ }
+ /* We need to check recursively if the backreference can epsilon
+ transit. */
+ if (subexp_len == 0
+ && mctx->state_log[cur_str_idx]->nodes.nelem > prev_nelem)
+ {
+ err = check_subexp_matching_top (mctx, new_dest_nodes,
+ cur_str_idx);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+ err = transit_state_bkref (mctx, new_dest_nodes);
+ if (BE (err != REG_NOERROR, 0))
+ goto free_return;
+ }
+ }
+ }
+ err = REG_NOERROR;
+ free_return:
+ return err;
+}
+
+/* Enumerate all the candidates which the backreference BKREF_NODE can match
+ at BKREF_STR_IDX, and register them by match_ctx_add_entry().
+ Note that we might collect inappropriate candidates here.
+ However, the cost of checking them strictly here is too high, then we
+ delay these checking for prune_impossible_nodes(). */
+
+static reg_errcode_t
+internal_function
+get_subexp (re_match_context_t *mctx, int bkref_node, int bkref_str_idx)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ int subexp_num, sub_top_idx;
+ const char *buf = (const char *) re_string_get_buffer (&mctx->input);
+ /* Return if we have already checked BKREF_NODE at BKREF_STR_IDX. */
+ int cache_idx = search_cur_bkref_entry (mctx, bkref_str_idx);
+ if (cache_idx != -1)
+ {
+ const struct re_backref_cache_entry *entry
+ = mctx->bkref_ents + cache_idx;
+ do
+ if (entry->node == bkref_node)
+ return REG_NOERROR; /* We already checked it. */
+ while (entry++->more);
+ }
+
+ subexp_num = dfa->nodes[bkref_node].opr.idx;
+
+ /* For each sub expression */
+ for (sub_top_idx = 0; sub_top_idx < mctx->nsub_tops; ++sub_top_idx)
+ {
+ reg_errcode_t err;
+ re_sub_match_top_t *sub_top = mctx->sub_tops[sub_top_idx];
+ re_sub_match_last_t *sub_last;
+ int sub_last_idx, sl_str, bkref_str_off;
+
+ if (dfa->nodes[sub_top->node].opr.idx != subexp_num)
+ continue; /* It isn't related. */
+
+ sl_str = sub_top->str_idx;
+ bkref_str_off = bkref_str_idx;
+ /* At first, check the last node of sub expressions we already
+ evaluated. */
+ for (sub_last_idx = 0; sub_last_idx < sub_top->nlasts; ++sub_last_idx)
+ {
+ int sl_str_diff;
+ sub_last = sub_top->lasts[sub_last_idx];
+ sl_str_diff = sub_last->str_idx - sl_str;
+ /* The matched string by the sub expression match with the substring
+ at the back reference? */
+ if (sl_str_diff > 0)
+ {
+ if (BE (bkref_str_off + sl_str_diff > mctx->input.valid_len, 0))
+ {
+ /* Not enough chars for a successful match. */
+ if (bkref_str_off + sl_str_diff > mctx->input.len)
+ break;
+
+ err = clean_state_log_if_needed (mctx,
+ bkref_str_off
+ + sl_str_diff);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ buf = (const char *) re_string_get_buffer (&mctx->input);
+ }
+ if (memcmp (buf + bkref_str_off, buf + sl_str, sl_str_diff) != 0)
+ /* We don't need to search this sub expression any more. */
+ break;
+ }
+ bkref_str_off += sl_str_diff;
+ sl_str += sl_str_diff;
+ err = get_subexp_sub (mctx, sub_top, sub_last, bkref_node,
+ bkref_str_idx);
+
+ /* Reload buf, since the preceding call might have reallocated
+ the buffer. */
+ buf = (const char *) re_string_get_buffer (&mctx->input);
+
+ if (err == REG_NOMATCH)
+ continue;
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+
+ if (sub_last_idx < sub_top->nlasts)
+ continue;
+ if (sub_last_idx > 0)
+ ++sl_str;
+ /* Then, search for the other last nodes of the sub expression. */
+ for (; sl_str <= bkref_str_idx; ++sl_str)
+ {
+ int cls_node, sl_str_off;
+ const re_node_set *nodes;
+ sl_str_off = sl_str - sub_top->str_idx;
+ /* The matched string by the sub expression match with the substring
+ at the back reference? */
+ if (sl_str_off > 0)
+ {
+ if (BE (bkref_str_off >= mctx->input.valid_len, 0))
+ {
+ /* If we are at the end of the input, we cannot match. */
+ if (bkref_str_off >= mctx->input.len)
+ break;
+
+ err = extend_buffers (mctx);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+
+ buf = (const char *) re_string_get_buffer (&mctx->input);
+ }
+ if (buf [bkref_str_off++] != buf[sl_str - 1])
+ break; /* We don't need to search this sub expression
+ any more. */
+ }
+ if (mctx->state_log[sl_str] == NULL)
+ continue;
+ /* Does this state have a ')' of the sub expression? */
+ nodes = &mctx->state_log[sl_str]->nodes;
+ cls_node = find_subexp_node (dfa, nodes, subexp_num,
+ OP_CLOSE_SUBEXP);
+ if (cls_node == -1)
+ continue; /* No. */
+ if (sub_top->path == NULL)
+ {
+ sub_top->path = calloc (sizeof (state_array_t),
+ sl_str - sub_top->str_idx + 1);
+ if (sub_top->path == NULL)
+ return REG_ESPACE;
+ }
+ /* Can the OP_OPEN_SUBEXP node arrive the OP_CLOSE_SUBEXP node
+ in the current context? */
+ err = check_arrival (mctx, sub_top->path, sub_top->node,
+ sub_top->str_idx, cls_node, sl_str,
+ OP_CLOSE_SUBEXP);
+ if (err == REG_NOMATCH)
+ continue;
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ sub_last = match_ctx_add_sublast (sub_top, cls_node, sl_str);
+ if (BE (sub_last == NULL, 0))
+ return REG_ESPACE;
+ err = get_subexp_sub (mctx, sub_top, sub_last, bkref_node,
+ bkref_str_idx);
+ if (err == REG_NOMATCH)
+ continue;
+ }
+ }
+ return REG_NOERROR;
+}
+
+/* Helper functions for get_subexp(). */
+
+/* Check SUB_LAST can arrive to the back reference BKREF_NODE at BKREF_STR.
+ If it can arrive, register the sub expression expressed with SUB_TOP
+ and SUB_LAST. */
+
+static reg_errcode_t
+internal_function
+get_subexp_sub (re_match_context_t *mctx, const re_sub_match_top_t *sub_top,
+ re_sub_match_last_t *sub_last, int bkref_node, int bkref_str)
+{
+ reg_errcode_t err;
+ int to_idx;
+ /* Can the subexpression arrive the back reference? */
+ err = check_arrival (mctx, &sub_last->path, sub_last->node,
+ sub_last->str_idx, bkref_node, bkref_str,
+ OP_OPEN_SUBEXP);
+ if (err != REG_NOERROR)
+ return err;
+ err = match_ctx_add_entry (mctx, bkref_node, bkref_str, sub_top->str_idx,
+ sub_last->str_idx);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ to_idx = bkref_str + sub_last->str_idx - sub_top->str_idx;
+ return clean_state_log_if_needed (mctx, to_idx);
+}
+
+/* Find the first node which is '(' or ')' and whose index is SUBEXP_IDX.
+ Search '(' if FL_OPEN, or search ')' otherwise.
+ TODO: This function isn't efficient...
+ Because there might be more than one nodes whose types are
+ OP_OPEN_SUBEXP and whose index is SUBEXP_IDX, we must check all
+ nodes.
+ E.g. RE: (a){2} */
+
+static int
+internal_function
+find_subexp_node (const re_dfa_t *dfa, const re_node_set *nodes,
+ int subexp_idx, int type)
+{
+ int cls_idx;
+ for (cls_idx = 0; cls_idx < nodes->nelem; ++cls_idx)
+ {
+ int cls_node = nodes->elems[cls_idx];
+ const re_token_t *node = dfa->nodes + cls_node;
+ if (node->type == type
+ && node->opr.idx == subexp_idx)
+ return cls_node;
+ }
+ return -1;
+}
+
+/* Check whether the node TOP_NODE at TOP_STR can arrive to the node
+ LAST_NODE at LAST_STR. We record the path onto PATH since it will be
+ heavily reused.
+ Return REG_NOERROR if it can arrive, or REG_NOMATCH otherwise. */
+
+static reg_errcode_t
+internal_function
+check_arrival (re_match_context_t *mctx, state_array_t *path, int top_node,
+ int top_str, int last_node, int last_str, int type)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ reg_errcode_t err = REG_NOERROR;
+ int subexp_num, backup_cur_idx, str_idx, null_cnt;
+ re_dfastate_t *cur_state = NULL;
+ re_node_set *cur_nodes, next_nodes;
+ re_dfastate_t **backup_state_log;
+ unsigned int context;
+
+ subexp_num = dfa->nodes[top_node].opr.idx;
+ /* Extend the buffer if we need. */
+ if (BE (path->alloc < last_str + mctx->max_mb_elem_len + 1, 0))
+ {
+ re_dfastate_t **new_array;
+ int old_alloc = path->alloc;
+ path->alloc += last_str + mctx->max_mb_elem_len + 1;
+ new_array = re_realloc (path->array, re_dfastate_t *, path->alloc);
+ if (BE (new_array == NULL, 0))
+ {
+ path->alloc = old_alloc;
+ return REG_ESPACE;
+ }
+ path->array = new_array;
+ memset (new_array + old_alloc, '\0',
+ sizeof (re_dfastate_t *) * (path->alloc - old_alloc));
+ }
+
+ str_idx = path->next_idx ? path->next_idx : top_str;
+
+ /* Temporary modify MCTX. */
+ backup_state_log = mctx->state_log;
+ backup_cur_idx = mctx->input.cur_idx;
+ mctx->state_log = path->array;
+ mctx->input.cur_idx = str_idx;
+
+ /* Setup initial node set. */
+ context = re_string_context_at (&mctx->input, str_idx - 1, mctx->eflags);
+ if (str_idx == top_str)
+ {
+ err = re_node_set_init_1 (&next_nodes, top_node);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ err = check_arrival_expand_ecl (dfa, &next_nodes, subexp_num, type);
+ if (BE (err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&next_nodes);
+ return err;
+ }
+ }
+ else
+ {
+ cur_state = mctx->state_log[str_idx];
+ if (cur_state && cur_state->has_backref)
+ {
+ err = re_node_set_init_copy (&next_nodes, &cur_state->nodes);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+ else
+ re_node_set_init_empty (&next_nodes);
+ }
+ if (str_idx == top_str || (cur_state && cur_state->has_backref))
+ {
+ if (next_nodes.nelem)
+ {
+ err = expand_bkref_cache (mctx, &next_nodes, str_idx,
+ subexp_num, type);
+ if (BE (err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&next_nodes);
+ return err;
+ }
+ }
+ cur_state = re_acquire_state_context (&err, dfa, &next_nodes, context);
+ if (BE (cur_state == NULL && err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&next_nodes);
+ return err;
+ }
+ mctx->state_log[str_idx] = cur_state;
+ }
+
+ for (null_cnt = 0; str_idx < last_str && null_cnt <= mctx->max_mb_elem_len;)
+ {
+ re_node_set_empty (&next_nodes);
+ if (mctx->state_log[str_idx + 1])
+ {
+ err = re_node_set_merge (&next_nodes,
+ &mctx->state_log[str_idx + 1]->nodes);
+ if (BE (err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&next_nodes);
+ return err;
+ }
+ }
+ if (cur_state)
+ {
+ err = check_arrival_add_next_nodes (mctx, str_idx,
+ &cur_state->non_eps_nodes,
+ &next_nodes);
+ if (BE (err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&next_nodes);
+ return err;
+ }
+ }
+ ++str_idx;
+ if (next_nodes.nelem)
+ {
+ err = check_arrival_expand_ecl (dfa, &next_nodes, subexp_num, type);
+ if (BE (err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&next_nodes);
+ return err;
+ }
+ err = expand_bkref_cache (mctx, &next_nodes, str_idx,
+ subexp_num, type);
+ if (BE (err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&next_nodes);
+ return err;
+ }
+ }
+ context = re_string_context_at (&mctx->input, str_idx - 1, mctx->eflags);
+ cur_state = re_acquire_state_context (&err, dfa, &next_nodes, context);
+ if (BE (cur_state == NULL && err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&next_nodes);
+ return err;
+ }
+ mctx->state_log[str_idx] = cur_state;
+ null_cnt = cur_state == NULL ? null_cnt + 1 : 0;
+ }
+ re_node_set_free (&next_nodes);
+ cur_nodes = (mctx->state_log[last_str] == NULL ? NULL
+ : &mctx->state_log[last_str]->nodes);
+ path->next_idx = str_idx;
+
+ /* Fix MCTX. */
+ mctx->state_log = backup_state_log;
+ mctx->input.cur_idx = backup_cur_idx;
+
+ /* Then check the current node set has the node LAST_NODE. */
+ if (cur_nodes != NULL && re_node_set_contains (cur_nodes, last_node))
+ return REG_NOERROR;
+
+ return REG_NOMATCH;
+}
+
+/* Helper functions for check_arrival. */
+
+/* Calculate the destination nodes of CUR_NODES at STR_IDX, and append them
+ to NEXT_NODES.
+ TODO: This function is similar to the functions transit_state*(),
+ however this function has many additional works.
+ Can't we unify them? */
+
+static reg_errcode_t
+internal_function
+check_arrival_add_next_nodes (re_match_context_t *mctx, int str_idx,
+ re_node_set *cur_nodes, re_node_set *next_nodes)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ int result;
+ int cur_idx;
+ reg_errcode_t err = REG_NOERROR;
+ re_node_set union_set;
+ re_node_set_init_empty (&union_set);
+ for (cur_idx = 0; cur_idx < cur_nodes->nelem; ++cur_idx)
+ {
+ int naccepted = 0;
+ int cur_node = cur_nodes->elems[cur_idx];
+#ifdef DEBUG
+ re_token_type_t type = dfa->nodes[cur_node].type;
+ assert (!IS_EPSILON_NODE (type));
+#endif
+#ifdef RE_ENABLE_I18N
+ /* If the node may accept `multi byte'. */
+ if (dfa->nodes[cur_node].accept_mb)
+ {
+ naccepted = check_node_accept_bytes (dfa, cur_node, &mctx->input,
+ str_idx);
+ if (naccepted > 1)
+ {
+ re_dfastate_t *dest_state;
+ int next_node = dfa->nexts[cur_node];
+ int next_idx = str_idx + naccepted;
+ dest_state = mctx->state_log[next_idx];
+ re_node_set_empty (&union_set);
+ if (dest_state)
+ {
+ err = re_node_set_merge (&union_set, &dest_state->nodes);
+ if (BE (err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&union_set);
+ return err;
+ }
+ }
+ result = re_node_set_insert (&union_set, next_node);
+ if (BE (result < 0, 0))
+ {
+ re_node_set_free (&union_set);
+ return REG_ESPACE;
+ }
+ mctx->state_log[next_idx] = re_acquire_state (&err, dfa,
+ &union_set);
+ if (BE (mctx->state_log[next_idx] == NULL
+ && err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&union_set);
+ return err;
+ }
+ }
+ }
+#endif /* RE_ENABLE_I18N */
+ if (naccepted
+ || check_node_accept (mctx, dfa->nodes + cur_node, str_idx))
+ {
+ result = re_node_set_insert (next_nodes, dfa->nexts[cur_node]);
+ if (BE (result < 0, 0))
+ {
+ re_node_set_free (&union_set);
+ return REG_ESPACE;
+ }
+ }
+ }
+ re_node_set_free (&union_set);
+ return REG_NOERROR;
+}
+
+/* For all the nodes in CUR_NODES, add the epsilon closures of them to
+ CUR_NODES, however exclude the nodes which are:
+ - inside the sub expression whose number is EX_SUBEXP, if FL_OPEN.
+ - out of the sub expression whose number is EX_SUBEXP, if !FL_OPEN.
+*/
+
+static reg_errcode_t
+internal_function
+check_arrival_expand_ecl (const re_dfa_t *dfa, re_node_set *cur_nodes,
+ int ex_subexp, int type)
+{
+ reg_errcode_t err;
+ int idx, outside_node;
+ re_node_set new_nodes;
+#ifdef DEBUG
+ assert (cur_nodes->nelem);
+#endif
+ err = re_node_set_alloc (&new_nodes, cur_nodes->nelem);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ /* Create a new node set NEW_NODES with the nodes which are epsilon
+ closures of the node in CUR_NODES. */
+
+ for (idx = 0; idx < cur_nodes->nelem; ++idx)
+ {
+ int cur_node = cur_nodes->elems[idx];
+ const re_node_set *eclosure = dfa->eclosures + cur_node;
+ outside_node = find_subexp_node (dfa, eclosure, ex_subexp, type);
+ if (outside_node == -1)
+ {
+ /* There are no problematic nodes, just merge them. */
+ err = re_node_set_merge (&new_nodes, eclosure);
+ if (BE (err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&new_nodes);
+ return err;
+ }
+ }
+ else
+ {
+ /* There are problematic nodes, re-calculate incrementally. */
+ err = check_arrival_expand_ecl_sub (dfa, &new_nodes, cur_node,
+ ex_subexp, type);
+ if (BE (err != REG_NOERROR, 0))
+ {
+ re_node_set_free (&new_nodes);
+ return err;
+ }
+ }
+ }
+ re_node_set_free (cur_nodes);
+ *cur_nodes = new_nodes;
+ return REG_NOERROR;
+}
+
+/* Helper function for check_arrival_expand_ecl.
+ Check incrementally the epsilon closure of TARGET, and if it isn't
+ problematic append it to DST_NODES. */
+
+static reg_errcode_t
+internal_function
+check_arrival_expand_ecl_sub (const re_dfa_t *dfa, re_node_set *dst_nodes,
+ int target, int ex_subexp, int type)
+{
+ int cur_node;
+ for (cur_node = target; !re_node_set_contains (dst_nodes, cur_node);)
+ {
+ int err;
+
+ if (dfa->nodes[cur_node].type == type
+ && dfa->nodes[cur_node].opr.idx == ex_subexp)
+ {
+ if (type == OP_CLOSE_SUBEXP)
+ {
+ err = re_node_set_insert (dst_nodes, cur_node);
+ if (BE (err == -1, 0))
+ return REG_ESPACE;
+ }
+ break;
+ }
+ err = re_node_set_insert (dst_nodes, cur_node);
+ if (BE (err == -1, 0))
+ return REG_ESPACE;
+ if (dfa->edests[cur_node].nelem == 0)
+ break;
+ if (dfa->edests[cur_node].nelem == 2)
+ {
+ err = check_arrival_expand_ecl_sub (dfa, dst_nodes,
+ dfa->edests[cur_node].elems[1],
+ ex_subexp, type);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+ cur_node = dfa->edests[cur_node].elems[0];
+ }
+ return REG_NOERROR;
+}
+
+
+/* For all the back references in the current state, calculate the
+ destination of the back references by the appropriate entry
+ in MCTX->BKREF_ENTS. */
+
+static reg_errcode_t
+internal_function
+expand_bkref_cache (re_match_context_t *mctx, re_node_set *cur_nodes,
+ int cur_str, int subexp_num, int type)
+{
+ const re_dfa_t *const dfa = mctx->dfa;
+ reg_errcode_t err;
+ int cache_idx_start = search_cur_bkref_entry (mctx, cur_str);
+ struct re_backref_cache_entry *ent;
+
+ if (cache_idx_start == -1)
+ return REG_NOERROR;
+
+ restart:
+ ent = mctx->bkref_ents + cache_idx_start;
+ do
+ {
+ int to_idx, next_node;
+
+ /* Is this entry ENT is appropriate? */
+ if (!re_node_set_contains (cur_nodes, ent->node))
+ continue; /* No. */
+
+ to_idx = cur_str + ent->subexp_to - ent->subexp_from;
+ /* Calculate the destination of the back reference, and append it
+ to MCTX->STATE_LOG. */
+ if (to_idx == cur_str)
+ {
+ /* The backreference did epsilon transit, we must re-check all the
+ node in the current state. */
+ re_node_set new_dests;
+ reg_errcode_t err2, err3;
+ next_node = dfa->edests[ent->node].elems[0];
+ if (re_node_set_contains (cur_nodes, next_node))
+ continue;
+ err = re_node_set_init_1 (&new_dests, next_node);
+ err2 = check_arrival_expand_ecl (dfa, &new_dests, subexp_num, type);
+ err3 = re_node_set_merge (cur_nodes, &new_dests);
+ re_node_set_free (&new_dests);
+ if (BE (err != REG_NOERROR || err2 != REG_NOERROR
+ || err3 != REG_NOERROR, 0))
+ {
+ err = (err != REG_NOERROR ? err
+ : (err2 != REG_NOERROR ? err2 : err3));
+ return err;
+ }
+ /* TODO: It is still inefficient... */
+ goto restart;
+ }
+ else
+ {
+ re_node_set union_set;
+ next_node = dfa->nexts[ent->node];
+ if (mctx->state_log[to_idx])
+ {
+ int ret;
+ if (re_node_set_contains (&mctx->state_log[to_idx]->nodes,
+ next_node))
+ continue;
+ err = re_node_set_init_copy (&union_set,
+ &mctx->state_log[to_idx]->nodes);
+ ret = re_node_set_insert (&union_set, next_node);
+ if (BE (err != REG_NOERROR || ret < 0, 0))
+ {
+ re_node_set_free (&union_set);
+ err = err != REG_NOERROR ? err : REG_ESPACE;
+ return err;
+ }
+ }
+ else
+ {
+ err = re_node_set_init_1 (&union_set, next_node);
+ if (BE (err != REG_NOERROR, 0))
+ return err;
+ }
+ mctx->state_log[to_idx] = re_acquire_state (&err, dfa, &union_set);
+ re_node_set_free (&union_set);
+ if (BE (mctx->state_log[to_idx] == NULL
+ && err != REG_NOERROR, 0))
+ return err;
+ }
+ }
+ while (ent++->more);
+ return REG_NOERROR;
+}
+
+/* Build transition table for the state.
+ Return 1 if succeeded, otherwise return NULL. */
+
+static int
+internal_function
+build_trtable (const re_dfa_t *dfa, re_dfastate_t *state)
+{
+ reg_errcode_t err;
+ int i, j, ch, need_word_trtable = 0;
+ bitset_word_t elem, mask;
+ bool dests_node_malloced = false;
+ bool dest_states_malloced = false;
+ int ndests; /* Number of the destination states from `state'. */
+ re_dfastate_t **trtable;
+ re_dfastate_t **dest_states = NULL, **dest_states_word, **dest_states_nl;
+ re_node_set follows, *dests_node;
+ bitset_t *dests_ch;
+ bitset_t acceptable;
+
+ struct dests_alloc
+ {
+ re_node_set dests_node[SBC_MAX];
+ bitset_t dests_ch[SBC_MAX];
+ } *dests_alloc;
+
+ /* We build DFA states which corresponds to the destination nodes
+ from `state'. `dests_node[i]' represents the nodes which i-th
+ destination state contains, and `dests_ch[i]' represents the
+ characters which i-th destination state accepts. */
+#ifdef HAVE_ALLOCA
+ if (__libc_use_alloca (sizeof (struct dests_alloc)))
+ dests_alloc = (struct dests_alloc *) alloca (sizeof (struct dests_alloc));
+ else
+#endif
+ {
+ dests_alloc = re_malloc (struct dests_alloc, 1);
+ if (BE (dests_alloc == NULL, 0))
+ return 0;
+ dests_node_malloced = true;
+ }
+ dests_node = dests_alloc->dests_node;
+ dests_ch = dests_alloc->dests_ch;
+
+ /* Initialize transiton table. */
+ state->word_trtable = state->trtable = NULL;
+
+ /* At first, group all nodes belonging to `state' into several
+ destinations. */
+ ndests = group_nodes_into_DFAstates (dfa, state, dests_node, dests_ch);
+ if (BE (ndests <= 0, 0))
+ {
+ if (dests_node_malloced)
+ free (dests_alloc);
+ /* Return 0 in case of an error, 1 otherwise. */
+ if (ndests == 0)
+ {
+ state->trtable = (re_dfastate_t **)
+ calloc (sizeof (re_dfastate_t *), SBC_MAX);
+ return 1;
+ }
+ return 0;
+ }
+
+ err = re_node_set_alloc (&follows, ndests + 1);
+ if (BE (err != REG_NOERROR, 0))
+ goto out_free;
+
+ /* Avoid arithmetic overflow in size calculation. */
+ if (BE ((((SIZE_MAX - (sizeof (re_node_set) + sizeof (bitset_t)) * SBC_MAX)
+ / (3 * sizeof (re_dfastate_t *)))
+ < ndests),
+ 0))
+ goto out_free;
+
+#ifdef HAVE_ALLOCA
+ if (__libc_use_alloca ((sizeof (re_node_set) + sizeof (bitset_t)) * SBC_MAX
+ + ndests * 3 * sizeof (re_dfastate_t *)))
+ dest_states = (re_dfastate_t **)
+ alloca (ndests * 3 * sizeof (re_dfastate_t *));
+ else
+#endif
+ {
+ dest_states = (re_dfastate_t **)
+ malloc (ndests * 3 * sizeof (re_dfastate_t *));
+ if (BE (dest_states == NULL, 0))
+ {
+out_free:
+ if (dest_states_malloced)
+ free (dest_states);
+ re_node_set_free (&follows);
+ for (i = 0; i < ndests; ++i)
+ re_node_set_free (dests_node + i);
+ if (dests_node_malloced)
+ free (dests_alloc);
+ return 0;
+ }
+ dest_states_malloced = true;
+ }
+ dest_states_word = dest_states + ndests;
+ dest_states_nl = dest_states_word + ndests;
+ bitset_empty (acceptable);
+
+ /* Then build the states for all destinations. */
+ for (i = 0; i < ndests; ++i)
+ {
+ int next_node;
+ re_node_set_empty (&follows);
+ /* Merge the follows of this destination states. */
+ for (j = 0; j < dests_node[i].nelem; ++j)
+ {
+ next_node = dfa->nexts[dests_node[i].elems[j]];
+ if (next_node != -1)
+ {
+ err = re_node_set_merge (&follows, dfa->eclosures + next_node);
+ if (BE (err != REG_NOERROR, 0))
+ goto out_free;
+ }
+ }
+ dest_states[i] = re_acquire_state_context (&err, dfa, &follows, 0);
+ if (BE (dest_states[i] == NULL && err != REG_NOERROR, 0))
+ goto out_free;
+ /* If the new state has context constraint,
+ build appropriate states for these contexts. */
+ if (dest_states[i]->has_constraint)
+ {
+ dest_states_word[i] = re_acquire_state_context (&err, dfa, &follows,
+ CONTEXT_WORD);
+ if (BE (dest_states_word[i] == NULL && err != REG_NOERROR, 0))
+ goto out_free;
+
+ if (dest_states[i] != dest_states_word[i] && dfa->mb_cur_max > 1)
+ need_word_trtable = 1;
+
+ dest_states_nl[i] = re_acquire_state_context (&err, dfa, &follows,
+ CONTEXT_NEWLINE);
+ if (BE (dest_states_nl[i] == NULL && err != REG_NOERROR, 0))
+ goto out_free;
+ }
+ else
+ {
+ dest_states_word[i] = dest_states[i];
+ dest_states_nl[i] = dest_states[i];
+ }
+ bitset_merge (acceptable, dests_ch[i]);
+ }
+
+ if (!BE (need_word_trtable, 0))
+ {
+ /* We don't care about whether the following character is a word
+ character, or we are in a single-byte character set so we can
+ discern by looking at the character code: allocate a
+ 256-entry transition table. */
+ trtable = state->trtable =
+ (re_dfastate_t **) calloc (sizeof (re_dfastate_t *), SBC_MAX);
+ if (BE (trtable == NULL, 0))
+ goto out_free;
+
+ /* For all characters ch...: */
+ for (i = 0; i < BITSET_WORDS; ++i)
+ for (ch = i * BITSET_WORD_BITS, elem = acceptable[i], mask = 1;
+ elem;
+ mask <<= 1, elem >>= 1, ++ch)
+ if (BE (elem & 1, 0))
+ {
+ /* There must be exactly one destination which accepts
+ character ch. See group_nodes_into_DFAstates. */
+ for (j = 0; (dests_ch[j][i] & mask) == 0; ++j)
+ ;
+
+ /* j-th destination accepts the word character ch. */
+ if (dfa->word_char[i] & mask)
+ trtable[ch] = dest_states_word[j];
+ else
+ trtable[ch] = dest_states[j];
+ }
+ }
+ else
+ {
+ /* We care about whether the following character is a word
+ character, and we are in a multi-byte character set: discern
+ by looking at the character code: build two 256-entry
+ transition tables, one starting at trtable[0] and one
+ starting at trtable[SBC_MAX]. */
+ trtable = state->word_trtable =
+ (re_dfastate_t **) calloc (sizeof (re_dfastate_t *), 2 * SBC_MAX);
+ if (BE (trtable == NULL, 0))
+ goto out_free;
+
+ /* For all characters ch...: */
+ for (i = 0; i < BITSET_WORDS; ++i)
+ for (ch = i * BITSET_WORD_BITS, elem = acceptable[i], mask = 1;
+ elem;
+ mask <<= 1, elem >>= 1, ++ch)
+ if (BE (elem & 1, 0))
+ {
+ /* There must be exactly one destination which accepts
+ character ch. See group_nodes_into_DFAstates. */
+ for (j = 0; (dests_ch[j][i] & mask) == 0; ++j)
+ ;
+
+ /* j-th destination accepts the word character ch. */
+ trtable[ch] = dest_states[j];
+ trtable[ch + SBC_MAX] = dest_states_word[j];
+ }
+ }
+
+ /* new line */
+ if (bitset_contain (acceptable, NEWLINE_CHAR))
+ {
+ /* The current state accepts newline character. */
+ for (j = 0; j < ndests; ++j)
+ if (bitset_contain (dests_ch[j], NEWLINE_CHAR))
+ {
+ /* k-th destination accepts newline character. */
+ trtable[NEWLINE_CHAR] = dest_states_nl[j];
+ if (need_word_trtable)
+ trtable[NEWLINE_CHAR + SBC_MAX] = dest_states_nl[j];
+ /* There must be only one destination which accepts
+ newline. See group_nodes_into_DFAstates. */
+ break;
+ }
+ }
+
+ if (dest_states_malloced)
+ free (dest_states);
+
+ re_node_set_free (&follows);
+ for (i = 0; i < ndests; ++i)
+ re_node_set_free (dests_node + i);
+
+ if (dests_node_malloced)
+ free (dests_alloc);
+
+ return 1;
+}
+
+/* Group all nodes belonging to STATE into several destinations.
+ Then for all destinations, set the nodes belonging to the destination
+ to DESTS_NODE[i] and set the characters accepted by the destination
+ to DEST_CH[i]. This function return the number of destinations. */
+
+static int
+internal_function
+group_nodes_into_DFAstates (const re_dfa_t *dfa, const re_dfastate_t *state,
+ re_node_set *dests_node, bitset_t *dests_ch)
+{
+ reg_errcode_t err;
+ int result;
+ int i, j, k;
+ int ndests; /* Number of the destinations from `state'. */
+ bitset_t accepts; /* Characters a node can accept. */
+ const re_node_set *cur_nodes = &state->nodes;
+ bitset_empty (accepts);
+ ndests = 0;
+
+ /* For all the nodes belonging to `state', */
+ for (i = 0; i < cur_nodes->nelem; ++i)
+ {
+ re_token_t *node = &dfa->nodes[cur_nodes->elems[i]];
+ re_token_type_t type = node->type;
+ unsigned int constraint = node->constraint;
+
+ /* Enumerate all single byte character this node can accept. */
+ if (type == CHARACTER)
+ bitset_set (accepts, node->opr.c);
+ else if (type == SIMPLE_BRACKET)
+ {
+ bitset_merge (accepts, node->opr.sbcset);
+ }
+ else if (type == OP_PERIOD)
+ {
+#ifdef RE_ENABLE_I18N
+ if (dfa->mb_cur_max > 1)
+ bitset_merge (accepts, dfa->sb_char);
+ else
+#endif
+ bitset_set_all (accepts);
+ if (!(dfa->syntax & RE_DOT_NEWLINE))
+ bitset_clear (accepts, '\n');
+ if (dfa->syntax & RE_DOT_NOT_NULL)
+ bitset_clear (accepts, '\0');
+ }
+#ifdef RE_ENABLE_I18N
+ else if (type == OP_UTF8_PERIOD)
+ {
+ memset (accepts, '\xff', sizeof (bitset_t) / 2);
+ if (!(dfa->syntax & RE_DOT_NEWLINE))
+ bitset_clear (accepts, '\n');
+ if (dfa->syntax & RE_DOT_NOT_NULL)
+ bitset_clear (accepts, '\0');
+ }
+#endif
+ else
+ continue;
+
+ /* Check the `accepts' and sift the characters which are not
+ match it the context. */
+ if (constraint)
+ {
+ if (constraint & NEXT_NEWLINE_CONSTRAINT)
+ {
+ bool accepts_newline = bitset_contain (accepts, NEWLINE_CHAR);
+ bitset_empty (accepts);
+ if (accepts_newline)
+ bitset_set (accepts, NEWLINE_CHAR);
+ else
+ continue;
+ }
+ if (constraint & NEXT_ENDBUF_CONSTRAINT)
+ {
+ bitset_empty (accepts);
+ continue;
+ }
+
+ if (constraint & NEXT_WORD_CONSTRAINT)
+ {
+ bitset_word_t any_set = 0;
+ if (type == CHARACTER && !node->word_char)
+ {
+ bitset_empty (accepts);
+ continue;
+ }
+#ifdef RE_ENABLE_I18N
+ if (dfa->mb_cur_max > 1)
+ for (j = 0; j < BITSET_WORDS; ++j)
+ any_set |= (accepts[j] &= (dfa->word_char[j] | ~dfa->sb_char[j]));
+ else
+#endif
+ for (j = 0; j < BITSET_WORDS; ++j)
+ any_set |= (accepts[j] &= dfa->word_char[j]);
+ if (!any_set)
+ continue;
+ }
+ if (constraint & NEXT_NOTWORD_CONSTRAINT)
+ {
+ bitset_word_t any_set = 0;
+ if (type == CHARACTER && node->word_char)
+ {
+ bitset_empty (accepts);
+ continue;
+ }
+#ifdef RE_ENABLE_I18N
+ if (dfa->mb_cur_max > 1)
+ for (j = 0; j < BITSET_WORDS; ++j)
+ any_set |= (accepts[j] &= ~(dfa->word_char[j] & dfa->sb_char[j]));
+ else
+#endif
+ for (j = 0; j < BITSET_WORDS; ++j)
+ any_set |= (accepts[j] &= ~dfa->word_char[j]);
+ if (!any_set)
+ continue;
+ }
+ }
+
+ /* Then divide `accepts' into DFA states, or create a new
+ state. Above, we make sure that accepts is not empty. */
+ for (j = 0; j < ndests; ++j)
+ {
+ bitset_t intersec; /* Intersection sets, see below. */
+ bitset_t remains;
+ /* Flags, see below. */
+ bitset_word_t has_intersec, not_subset, not_consumed;
+
+ /* Optimization, skip if this state doesn't accept the character. */
+ if (type == CHARACTER && !bitset_contain (dests_ch[j], node->opr.c))
+ continue;
+
+ /* Enumerate the intersection set of this state and `accepts'. */
+ has_intersec = 0;
+ for (k = 0; k < BITSET_WORDS; ++k)
+ has_intersec |= intersec[k] = accepts[k] & dests_ch[j][k];
+ /* And skip if the intersection set is empty. */
+ if (!has_intersec)
+ continue;
+
+ /* Then check if this state is a subset of `accepts'. */
+ not_subset = not_consumed = 0;
+ for (k = 0; k < BITSET_WORDS; ++k)
+ {
+ not_subset |= remains[k] = ~accepts[k] & dests_ch[j][k];
+ not_consumed |= accepts[k] = accepts[k] & ~dests_ch[j][k];
+ }
+
+ /* If this state isn't a subset of `accepts', create a
+ new group state, which has the `remains'. */
+ if (not_subset)
+ {
+ bitset_copy (dests_ch[ndests], remains);
+ bitset_copy (dests_ch[j], intersec);
+ err = re_node_set_init_copy (dests_node + ndests, &dests_node[j]);
+ if (BE (err != REG_NOERROR, 0))
+ goto error_return;
+ ++ndests;
+ }
+
+ /* Put the position in the current group. */
+ result = re_node_set_insert (&dests_node[j], cur_nodes->elems[i]);
+ if (BE (result < 0, 0))
+ goto error_return;
+
+ /* If all characters are consumed, go to next node. */
+ if (!not_consumed)
+ break;
+ }
+ /* Some characters remain, create a new group. */
+ if (j == ndests)
+ {
+ bitset_copy (dests_ch[ndests], accepts);
+ err = re_node_set_init_1 (dests_node + ndests, cur_nodes->elems[i]);
+ if (BE (err != REG_NOERROR, 0))
+ goto error_return;
+ ++ndests;
+ bitset_empty (accepts);
+ }
+ }
+ return ndests;
+ error_return:
+ for (j = 0; j < ndests; ++j)
+ re_node_set_free (dests_node + j);
+ return -1;
+}
+
+#ifdef RE_ENABLE_I18N
+/* Check how many bytes the node `dfa->nodes[node_idx]' accepts.
+ Return the number of the bytes the node accepts.
+ STR_IDX is the current index of the input string.
+
+ This function handles the nodes which can accept one character, or
+ one collating element like '.', '[a-z]', opposite to the other nodes
+ can only accept one byte. */
+
+static int
+internal_function
+check_node_accept_bytes (const re_dfa_t *dfa, int node_idx,
+ const re_string_t *input, int str_idx)
+{
+ const re_token_t *node = dfa->nodes + node_idx;
+ int char_len, elem_len;
+ int i;
+ wint_t wc;
+
+ if (BE (node->type == OP_UTF8_PERIOD, 0))
+ {
+ unsigned char c = re_string_byte_at (input, str_idx), d;
+ if (BE (c < 0xc2, 1))
+ return 0;
+
+ if (str_idx + 2 > input->len)
+ return 0;
+
+ d = re_string_byte_at (input, str_idx + 1);
+ if (c < 0xe0)
+ return (d < 0x80 || d > 0xbf) ? 0 : 2;
+ else if (c < 0xf0)
+ {
+ char_len = 3;
+ if (c == 0xe0 && d < 0xa0)
+ return 0;
+ }
+ else if (c < 0xf8)
+ {
+ char_len = 4;
+ if (c == 0xf0 && d < 0x90)
+ return 0;
+ }
+ else if (c < 0xfc)
+ {
+ char_len = 5;
+ if (c == 0xf8 && d < 0x88)
+ return 0;
+ }
+ else if (c < 0xfe)
+ {
+ char_len = 6;
+ if (c == 0xfc && d < 0x84)
+ return 0;
+ }
+ else
+ return 0;
+
+ if (str_idx + char_len > input->len)
+ return 0;
+
+ for (i = 1; i < char_len; ++i)
+ {
+ d = re_string_byte_at (input, str_idx + i);
+ if (d < 0x80 || d > 0xbf)
+ return 0;
+ }
+ return char_len;
+ }
+
+ char_len = re_string_char_size_at (input, str_idx);
+ if (node->type == OP_PERIOD)
+ {
+ if (char_len <= 1)
+ return 0;
+ /* FIXME: I don't think this if is needed, as both '\n'
+ and '\0' are char_len == 1. */
+ /* '.' accepts any one character except the following two cases. */
+ if ((!(dfa->syntax & RE_DOT_NEWLINE) &&
+ re_string_byte_at (input, str_idx) == '\n') ||
+ ((dfa->syntax & RE_DOT_NOT_NULL) &&
+ re_string_byte_at (input, str_idx) == '\0'))
+ return 0;
+ return char_len;
+ }
+
+ elem_len = re_string_elem_size_at (input, str_idx);
+ wc = __btowc(*(input->mbs+str_idx));
+ if (((elem_len <= 1 && char_len <= 1) || char_len == 0) && (wc != WEOF && wc < SBC_MAX))
+ return 0;
+
+ if (node->type == COMPLEX_BRACKET)
+ {
+ const re_charset_t *cset = node->opr.mbcset;
+# ifdef _LIBC
+ const unsigned char *pin
+ = ((const unsigned char *) re_string_get_buffer (input) + str_idx);
+ int j;
+ uint32_t nrules;
+# endif /* _LIBC */
+ int match_len = 0;
+ wchar_t wc = ((cset->nranges || cset->nchar_classes || cset->nmbchars)
+ ? re_string_wchar_at (input, str_idx) : 0);
+
+ /* match with multibyte character? */
+ for (i = 0; i < cset->nmbchars; ++i)
+ if (wc == cset->mbchars[i])
+ {
+ match_len = char_len;
+ goto check_node_accept_bytes_match;
+ }
+ /* match with character_class? */
+ for (i = 0; i < cset->nchar_classes; ++i)
+ {
+ wctype_t wt = cset->char_classes[i];
+ if (__iswctype (wc, wt))
+ {
+ match_len = char_len;
+ goto check_node_accept_bytes_match;
+ }
+ }
+
+# ifdef _LIBC
+ nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
+ if (nrules != 0)
+ {
+ unsigned int in_collseq = 0;
+ const int32_t *table, *indirect;
+ const unsigned char *weights, *extra;
+ const char *collseqwc;
+ /* This #include defines a local function! */
+# include <locale/weight.h>
+
+ /* match with collating_symbol? */
+ if (cset->ncoll_syms)
+ extra = (const unsigned char *)
+ _NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB);
+ for (i = 0; i < cset->ncoll_syms; ++i)
+ {
+ const unsigned char *coll_sym = extra + cset->coll_syms[i];
+ /* Compare the length of input collating element and
+ the length of current collating element. */
+ if (*coll_sym != elem_len)
+ continue;
+ /* Compare each bytes. */
+ for (j = 0; j < *coll_sym; j++)
+ if (pin[j] != coll_sym[1 + j])
+ break;
+ if (j == *coll_sym)
+ {
+ /* Match if every bytes is equal. */
+ match_len = j;
+ goto check_node_accept_bytes_match;
+ }
+ }
+
+ if (cset->nranges)
+ {
+ if (elem_len <= char_len)
+ {
+ collseqwc = _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQWC);
+ in_collseq = __collseq_table_lookup (collseqwc, wc);
+ }
+ else
+ in_collseq = find_collation_sequence_value (pin, elem_len);
+ }
+ /* match with range expression? */
+ for (i = 0; i < cset->nranges; ++i)
+ if (cset->range_starts[i] <= in_collseq
+ && in_collseq <= cset->range_ends[i])
+ {
+ match_len = elem_len;
+ goto check_node_accept_bytes_match;
+ }
+
+ /* match with equivalence_class? */
+ if (cset->nequiv_classes)
+ {
+ const unsigned char *cp = pin;
+ table = (const int32_t *)
+ _NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB);
+ weights = (const unsigned char *)
+ _NL_CURRENT (LC_COLLATE, _NL_COLLATE_WEIGHTMB);
+ extra = (const unsigned char *)
+ _NL_CURRENT (LC_COLLATE, _NL_COLLATE_EXTRAMB);
+ indirect = (const int32_t *)
+ _NL_CURRENT (LC_COLLATE, _NL_COLLATE_INDIRECTMB);
+ int32_t idx = findidx (&cp);
+ if (idx > 0)
+ for (i = 0; i < cset->nequiv_classes; ++i)
+ {
+ int32_t equiv_class_idx = cset->equiv_classes[i];
+ size_t weight_len = weights[idx & 0xffffff];
+ if (weight_len == weights[equiv_class_idx & 0xffffff]
+ && (idx >> 24) == (equiv_class_idx >> 24))
+ {
+ int cnt = 0;
+
+ idx &= 0xffffff;
+ equiv_class_idx &= 0xffffff;
+
+ while (cnt <= weight_len
+ && (weights[equiv_class_idx + 1 + cnt]
+ == weights[idx + 1 + cnt]))
+ ++cnt;
+ if (cnt > weight_len)
+ {
+ match_len = elem_len;
+ goto check_node_accept_bytes_match;
+ }
+ }
+ }
+ }
+ }
+ else
+# endif /* _LIBC */
+ {
+ /* match with range expression? */
+#if __GNUC__ >= 2
+ wchar_t cmp_buf[] = {L'\0', L'\0', wc, L'\0', L'\0', L'\0'};
+#else
+ wchar_t cmp_buf[] = {L'\0', L'\0', L'\0', L'\0', L'\0', L'\0'};
+ cmp_buf[2] = wc;
+#endif
+ for (i = 0; i < cset->nranges; ++i)
+ {
+ cmp_buf[0] = cset->range_starts[i];
+ cmp_buf[4] = cset->range_ends[i];
+ if (wcscoll (cmp_buf, cmp_buf + 2) <= 0
+ && wcscoll (cmp_buf + 2, cmp_buf + 4) <= 0)
+ {
+ match_len = char_len;
+ goto check_node_accept_bytes_match;
+ }
+ }
+ }
+ check_node_accept_bytes_match:
+ if (!cset->non_match)
+ return match_len;
+ else
+ {
+ if (match_len > 0)
+ return 0;
+ else
+ return (elem_len > char_len) ? elem_len : char_len;
+ }
+ }
+ return 0;
+}
+
+# ifdef _LIBC
+static unsigned int
+internal_function
+find_collation_sequence_value (const unsigned char *mbs, size_t mbs_len)
+{
+ uint32_t nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
+ if (nrules == 0)
+ {
+ if (mbs_len == 1)
+ {
+ /* No valid character. Match it as a single byte character. */
+ const unsigned char *collseq = (const unsigned char *)
+ _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQMB);
+ return collseq[mbs[0]];
+ }
+ return UINT_MAX;
+ }
+ else
+ {
+ int32_t idx;
+ const unsigned char *extra = (const unsigned char *)
+ _NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB);
+ int32_t extrasize = (const unsigned char *)
+ _NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB + 1) - extra;
+
+ for (idx = 0; idx < extrasize;)
+ {
+ int mbs_cnt, found = 0;
+ int32_t elem_mbs_len;
+ /* Skip the name of collating element name. */
+ idx = idx + extra[idx] + 1;
+ elem_mbs_len = extra[idx++];
+ if (mbs_len == elem_mbs_len)
+ {
+ for (mbs_cnt = 0; mbs_cnt < elem_mbs_len; ++mbs_cnt)
+ if (extra[idx + mbs_cnt] != mbs[mbs_cnt])
+ break;
+ if (mbs_cnt == elem_mbs_len)
+ /* Found the entry. */
+ found = 1;
+ }
+ /* Skip the byte sequence of the collating element. */
+ idx += elem_mbs_len;
+ /* Adjust for the alignment. */
+ idx = (idx + 3) & ~3;
+ /* Skip the collation sequence value. */
+ idx += sizeof (uint32_t);
+ /* Skip the wide char sequence of the collating element. */
+ idx = idx + sizeof (uint32_t) * (extra[idx] + 1);
+ /* If we found the entry, return the sequence value. */
+ if (found)
+ return *(uint32_t *) (extra + idx);
+ /* Skip the collation sequence value. */
+ idx += sizeof (uint32_t);
+ }
+ return UINT_MAX;
+ }
+}
+# endif /* _LIBC */
+#endif /* RE_ENABLE_I18N */
+
+/* Check whether the node accepts the byte which is IDX-th
+ byte of the INPUT. */
+
+static int
+internal_function
+check_node_accept (const re_match_context_t *mctx, const re_token_t *node,
+ int idx)
+{
+ unsigned char ch;
+ ch = re_string_byte_at (&mctx->input, idx);
+ switch (node->type)
+ {
+ case CHARACTER:
+ if (node->opr.c != ch)
+ return 0;
+ break;
+
+ case SIMPLE_BRACKET:
+ if (!bitset_contain (node->opr.sbcset, ch))
+ return 0;
+ break;
+
+#ifdef RE_ENABLE_I18N
+ case OP_UTF8_PERIOD:
+ if (ch >= 0x80)
+ return 0;
+ /* FALLTHROUGH */
+#endif
+ case OP_PERIOD:
+ if ((ch == '\n' && !(mctx->dfa->syntax & RE_DOT_NEWLINE))
+ || (ch == '\0' && (mctx->dfa->syntax & RE_DOT_NOT_NULL)))
+ return 0;
+ break;
+
+ default:
+ return 0;
+ }
+
+ if (node->constraint)
+ {
+ /* The node has constraints. Check whether the current context
+ satisfies the constraints. */
+ unsigned int context = re_string_context_at (&mctx->input, idx,
+ mctx->eflags);
+ if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context))
+ return 0;
+ }
+
+ return 1;
+}
+
+/* Extend the buffers, if the buffers have run out. */
+
+static reg_errcode_t
+internal_function
+extend_buffers (re_match_context_t *mctx)
+{
+ reg_errcode_t ret;
+ re_string_t *pstr = &mctx->input;
+
+ /* Avoid overflow. */
+ if (BE (INT_MAX / 2 / sizeof (re_dfastate_t *) <= pstr->bufs_len, 0))
+ return REG_ESPACE;
+
+ /* Double the lengthes of the buffers. */
+ ret = re_string_realloc_buffers (pstr, pstr->bufs_len * 2);
+ if (BE (ret != REG_NOERROR, 0))
+ return ret;
+
+ if (mctx->state_log != NULL)
+ {
+ /* And double the length of state_log. */
+ /* XXX We have no indication of the size of this buffer. If this
+ allocation fail we have no indication that the state_log array
+ does not have the right size. */
+ re_dfastate_t **new_array = re_realloc (mctx->state_log, re_dfastate_t *,
+ pstr->bufs_len + 1);
+ if (BE (new_array == NULL, 0))
+ return REG_ESPACE;
+ mctx->state_log = new_array;
+ }
+
+ /* Then reconstruct the buffers. */
+ if (pstr->icase)
+ {
+#ifdef RE_ENABLE_I18N
+ if (pstr->mb_cur_max > 1)
+ {
+ ret = build_wcs_upper_buffer (pstr);
+ if (BE (ret != REG_NOERROR, 0))
+ return ret;
+ }
+ else
+#endif /* RE_ENABLE_I18N */
+ build_upper_buffer (pstr);
+ }
+ else
+ {
+#ifdef RE_ENABLE_I18N
+ if (pstr->mb_cur_max > 1)
+ build_wcs_buffer (pstr);
+ else
+#endif /* RE_ENABLE_I18N */
+ {
+ if (pstr->trans != NULL)
+ re_string_translate_buffer (pstr);
+ }
+ }
+ return REG_NOERROR;
+}
+
+
+/* Functions for matching context. */
+
+/* Initialize MCTX. */
+
+static reg_errcode_t
+internal_function
+match_ctx_init (re_match_context_t *mctx, int eflags, int n)
+{
+ mctx->eflags = eflags;
+ mctx->match_last = -1;
+ if (n > 0)
+ {
+ mctx->bkref_ents = re_malloc (struct re_backref_cache_entry, n);
+ mctx->sub_tops = re_malloc (re_sub_match_top_t *, n);
+ if (BE (mctx->bkref_ents == NULL || mctx->sub_tops == NULL, 0))
+ return REG_ESPACE;
+ }
+ /* Already zero-ed by the caller.
+ else
+ mctx->bkref_ents = NULL;
+ mctx->nbkref_ents = 0;
+ mctx->nsub_tops = 0; */
+ mctx->abkref_ents = n;
+ mctx->max_mb_elem_len = 1;
+ mctx->asub_tops = n;
+ return REG_NOERROR;
+}
+
+/* Clean the entries which depend on the current input in MCTX.
+ This function must be invoked when the matcher changes the start index
+ of the input, or changes the input string. */
+
+static void
+internal_function
+match_ctx_clean (re_match_context_t *mctx)
+{
+ int st_idx;
+ for (st_idx = 0; st_idx < mctx->nsub_tops; ++st_idx)
+ {
+ int sl_idx;
+ re_sub_match_top_t *top = mctx->sub_tops[st_idx];
+ for (sl_idx = 0; sl_idx < top->nlasts; ++sl_idx)
+ {
+ re_sub_match_last_t *last = top->lasts[sl_idx];
+ re_free (last->path.array);
+ re_free (last);
+ }
+ re_free (top->lasts);
+ if (top->path)
+ {
+ re_free (top->path->array);
+ re_free (top->path);
+ }
+ free (top);
+ }
+
+ mctx->nsub_tops = 0;
+ mctx->nbkref_ents = 0;
+}
+
+/* Free all the memory associated with MCTX. */
+
+static void
+internal_function
+match_ctx_free (re_match_context_t *mctx)
+{
+ /* First, free all the memory associated with MCTX->SUB_TOPS. */
+ match_ctx_clean (mctx);
+ re_free (mctx->sub_tops);
+ re_free (mctx->bkref_ents);
+}
+
+/* Add a new backreference entry to MCTX.
+ Note that we assume that caller never call this function with duplicate
+ entry, and call with STR_IDX which isn't smaller than any existing entry.
+*/
+
+static reg_errcode_t
+internal_function
+match_ctx_add_entry (re_match_context_t *mctx, int node, int str_idx, int from,
+ int to)
+{
+ if (mctx->nbkref_ents >= mctx->abkref_ents)
+ {
+ struct re_backref_cache_entry* new_entry;
+ new_entry = re_realloc (mctx->bkref_ents, struct re_backref_cache_entry,
+ mctx->abkref_ents * 2);
+ if (BE (new_entry == NULL, 0))
+ {
+ re_free (mctx->bkref_ents);
+ return REG_ESPACE;
+ }
+ mctx->bkref_ents = new_entry;
+ memset (mctx->bkref_ents + mctx->nbkref_ents, '\0',
+ sizeof (struct re_backref_cache_entry) * mctx->abkref_ents);
+ mctx->abkref_ents *= 2;
+ }
+ if (mctx->nbkref_ents > 0
+ && mctx->bkref_ents[mctx->nbkref_ents - 1].str_idx == str_idx)
+ mctx->bkref_ents[mctx->nbkref_ents - 1].more = 1;
+
+ mctx->bkref_ents[mctx->nbkref_ents].node = node;
+ mctx->bkref_ents[mctx->nbkref_ents].str_idx = str_idx;
+ mctx->bkref_ents[mctx->nbkref_ents].subexp_from = from;
+ mctx->bkref_ents[mctx->nbkref_ents].subexp_to = to;
+
+ /* This is a cache that saves negative results of check_dst_limits_calc_pos.
+ If bit N is clear, means that this entry won't epsilon-transition to
+ an OP_OPEN_SUBEXP or OP_CLOSE_SUBEXP for the N+1-th subexpression. If
+ it is set, check_dst_limits_calc_pos_1 will recurse and try to find one
+ such node.
+
+ A backreference does not epsilon-transition unless it is empty, so set
+ to all zeros if FROM != TO. */
+ mctx->bkref_ents[mctx->nbkref_ents].eps_reachable_subexps_map
+ = (from == to ? ~0 : 0);
+
+ mctx->bkref_ents[mctx->nbkref_ents++].more = 0;
+ if (mctx->max_mb_elem_len < to - from)
+ mctx->max_mb_elem_len = to - from;
+ return REG_NOERROR;
+}
+
+/* Search for the first entry which has the same str_idx, or -1 if none is
+ found. Note that MCTX->BKREF_ENTS is already sorted by MCTX->STR_IDX. */
+
+static int
+internal_function
+search_cur_bkref_entry (const re_match_context_t *mctx, int str_idx)
+{
+ int left, right, mid, last;
+ last = right = mctx->nbkref_ents;
+ for (left = 0; left < right;)
+ {
+ mid = (left + right) / 2;
+ if (mctx->bkref_ents[mid].str_idx < str_idx)
+ left = mid + 1;
+ else
+ right = mid;
+ }
+ if (left < last && mctx->bkref_ents[left].str_idx == str_idx)
+ return left;
+ else
+ return -1;
+}
+
+/* Register the node NODE, whose type is OP_OPEN_SUBEXP, and which matches
+ at STR_IDX. */
+
+static reg_errcode_t
+internal_function
+match_ctx_add_subtop (re_match_context_t *mctx, int node, int str_idx)
+{
+#ifdef DEBUG
+ assert (mctx->sub_tops != NULL);
+ assert (mctx->asub_tops > 0);
+#endif
+ if (BE (mctx->nsub_tops == mctx->asub_tops, 0))
+ {
+ int new_asub_tops = mctx->asub_tops * 2;
+ re_sub_match_top_t **new_array = re_realloc (mctx->sub_tops,
+ re_sub_match_top_t *,
+ new_asub_tops);
+ if (BE (new_array == NULL, 0))
+ return REG_ESPACE;
+ mctx->sub_tops = new_array;
+ mctx->asub_tops = new_asub_tops;
+ }
+ mctx->sub_tops[mctx->nsub_tops] = calloc (1, sizeof (re_sub_match_top_t));
+ if (BE (mctx->sub_tops[mctx->nsub_tops] == NULL, 0))
+ return REG_ESPACE;
+ mctx->sub_tops[mctx->nsub_tops]->node = node;
+ mctx->sub_tops[mctx->nsub_tops++]->str_idx = str_idx;
+ return REG_NOERROR;
+}
+
+/* Register the node NODE, whose type is OP_CLOSE_SUBEXP, and which matches
+ at STR_IDX, whose corresponding OP_OPEN_SUBEXP is SUB_TOP. */
+
+static re_sub_match_last_t *
+internal_function
+match_ctx_add_sublast (re_sub_match_top_t *subtop, int node, int str_idx)
+{
+ re_sub_match_last_t *new_entry;
+ if (BE (subtop->nlasts == subtop->alasts, 0))
+ {
+ int new_alasts = 2 * subtop->alasts + 1;
+ re_sub_match_last_t **new_array = re_realloc (subtop->lasts,
+ re_sub_match_last_t *,
+ new_alasts);
+ if (BE (new_array == NULL, 0))
+ return NULL;
+ subtop->lasts = new_array;
+ subtop->alasts = new_alasts;
+ }
+ new_entry = calloc (1, sizeof (re_sub_match_last_t));
+ if (BE (new_entry != NULL, 1))
+ {
+ subtop->lasts[subtop->nlasts] = new_entry;
+ new_entry->node = node;
+ new_entry->str_idx = str_idx;
+ ++subtop->nlasts;
+ }
+ return new_entry;
+}
+
+static void
+internal_function
+sift_ctx_init (re_sift_context_t *sctx, re_dfastate_t **sifted_sts,
+ re_dfastate_t **limited_sts, int last_node, int last_str_idx)
+{
+ sctx->sifted_states = sifted_sts;
+ sctx->limited_states = limited_sts;
+ sctx->last_node = last_node;
+ sctx->last_str_idx = last_str_idx;
+ re_node_set_init_empty (&sctx->limits);
+}