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glibc/posix/regexec.c

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/* Extended regular expression matching and search library.
Copyright (C) 2002 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., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <assert.h>
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
#include <wctype.h>
#ifdef _LIBC
# ifndef _RE_DEFINE_LOCALE_FUNCTIONS
# define _RE_DEFINE_LOCALE_FUNCTIONS 1
# include <locale/localeinfo.h>
# include <locale/elem-hash.h>
# include <locale/coll-lookup.h>
# endif
#endif
#include "regex.h"
#include "regex_internal.h"
static reg_errcode_t match_ctx_init (re_match_context_t *cache, int eflags,
re_string_t *input, int n);
static void match_ctx_free (re_match_context_t *cache);
static reg_errcode_t match_ctx_add_entry (re_match_context_t *cache, int node,
int from, int to);
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);
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);
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);
static unsigned re_copy_regs (struct re_registers *regs, regmatch_t *pmatch,
int nregs, int regs_allocated);
static inline re_dfastate_t *acquire_init_state_context (reg_errcode_t *err,
const regex_t *preg,
const re_match_context_t *mctx,
int idx);
static int check_matching (const regex_t *preg, re_match_context_t *mctx,
int fl_search, int fl_longest_match);
static int check_halt_node_context (const re_dfa_t *dfa, int node,
unsigned int context);
static int check_halt_state_context (const regex_t *preg,
const re_dfastate_t *state,
const re_match_context_t *mctx, int idx);
static void update_regs (re_dfa_t *dfa, regmatch_t *pmatch, int cur_node,
int cur_idx, int nmatch);
static int proceed_next_node (const regex_t *preg,
const re_match_context_t *mctx,
int *pidx, int node, re_node_set *eps_via_nodes);
static reg_errcode_t set_regs (const regex_t *preg,
const re_match_context_t *mctx,
size_t nmatch, regmatch_t *pmatch, int last);
#ifdef RE_ENABLE_I18N
static int sift_states_iter_mb (const regex_t *preg,
const re_match_context_t *mctx,
int node_idx, int str_idx, int max_str_idx);
#endif /* RE_ENABLE_I18N */
static int sift_states_iter_bkref (const re_dfa_t *dfa,
re_dfastate_t **state_log,
struct re_backref_cache_entry *mctx_entry,
int node_idx, int idx, int match_last);
static reg_errcode_t sift_states_backward (const regex_t *preg,
const re_match_context_t *mctx,
int last_node);
static reg_errcode_t clean_state_log_if_need (re_match_context_t *mctx,
int next_state_log_idx);
static reg_errcode_t add_epsilon_backreference (const re_dfa_t *dfa,
const re_match_context_t *mctx,
const re_node_set *plog,
int idx,
re_node_set *state_buf);
static re_dfastate_t *transit_state (reg_errcode_t *err, const regex_t *preg,
re_match_context_t *mctx,
re_dfastate_t *state, int fl_search);
static re_dfastate_t *transit_state_sb (reg_errcode_t *err, const regex_t *preg,
re_dfastate_t *pstate,
int fl_search,
re_match_context_t *mctx);
#ifdef RE_ENABLE_I18N
static reg_errcode_t transit_state_mb (const regex_t *preg,
re_dfastate_t *pstate,
re_match_context_t *mctx);
#endif /* RE_ENABLE_I18N */
static reg_errcode_t transit_state_bkref (const regex_t *preg,
re_dfastate_t *pstate,
re_match_context_t *mctx);
static reg_errcode_t transit_state_bkref_loop (const regex_t *preg,
re_node_set *nodes,
re_dfastate_t **work_state_log,
re_match_context_t *mctx);
static re_dfastate_t **build_trtable (const regex_t *dfa,
const re_dfastate_t *state,
int fl_search);
#ifdef RE_ENABLE_I18N
static int check_node_accept_bytes (const regex_t *preg, int node_idx,
const re_string_t *input, int idx);
# ifdef _LIBC
static unsigned int find_collation_sequence_value (const unsigned char *mbs,
size_t name_len);
# endif /* _LIBC */
#endif /* RE_ENABLE_I18N */
static int group_nodes_into_DFAstates (const regex_t *dfa,
const re_dfastate_t *state,
re_node_set *states_node,
bitset *states_ch);
static int check_node_accept (const regex_t *preg, const re_token_t *node,
const re_match_context_t *mctx, int idx);
static reg_errcode_t extend_buffers (re_match_context_t *mctx);
/* 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 *preg;
const char *string;
size_t nmatch;
regmatch_t pmatch[];
int eflags;
{
reg_errcode_t err;
int length = strlen (string);
if (preg->no_sub)
err = re_search_internal (preg, string, length, 0, length, length, 0,
NULL, eflags);
else
err = re_search_internal (preg, string, length, 0, length, length, nmatch,
pmatch, eflags);
return err != REG_NOERROR;
}
#ifdef _LIBC
weak_alias (__regexec, regexec)
#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 || range < 0, 0))
return -1;
if (BE (start + range > length, 0))
range = length - start;
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))
return -2;
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);
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 (need_regs > regs->num_regs)
{
regs->start = re_realloc (regs->start, regoff_t, need_regs);
if (BE (regs->start == NULL, 0))
{
if (regs->end != NULL)
re_free (regs->end);
return REGS_UNALLOCATED;
}
regs->end = re_realloc (regs->end, regoff_t, need_regs);
if (BE (regs->end == NULL, 0))
{
re_free (regs->start);
return REGS_UNALLOCATED;
}
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 */
static re_node_set empty_set;
/* 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;
re_dfa_t *dfa = (re_dfa_t *)preg->buffer;
re_string_t input;
int left_lim, right_lim, incr;
int fl_longest_match, match_first, match_last = -1;
re_match_context_t mctx;
char *fastmap = ((preg->fastmap != NULL && preg->fastmap_accurate)
? preg->fastmap : NULL);
/* 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;
re_node_set_init_empty (&empty_set);
/* We must check the longest matching, if nmatch > 0. */
fl_longest_match = (nmatch != 0);
err = re_string_allocate (&input, string, length, dfa->nodes_len + 1,
preg->translate, preg->syntax & RE_ICASE);
if (BE (err != REG_NOERROR, 0))
return err;
input.stop = stop;
err = match_ctx_init (&mctx, eflags, &input, dfa->nbackref * 2);
if (BE (err != REG_NOERROR, 0))
return err;
/* 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)
{
mctx.state_log = re_malloc (re_dfastate_t *, dfa->nodes_len + 1);
if (BE (mctx.state_log == NULL, 0))
return REG_ESPACE;
}
else
mctx.state_log = NULL;
#ifdef DEBUG
/* We assume front-end functions already check them. */
assert (start + range >= 0 && start + range <= length);
#endif
match_first = start;
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;
for (;;)
{
/* At first get the current byte from input string. */
int ch;
if (MB_CUR_MAX > 1 && (preg->syntax & RE_ICASE || preg->translate))
{
/* In this case, we can't determin easily the current byte,
since it might be a component byte of a multibyte character.
Then we use the constructed buffer instead. */
/* If MATCH_FIRST is out of the valid range, reconstruct the
buffers. */
if (input.raw_mbs_idx + input.valid_len <= match_first)
re_string_reconstruct (&input, match_first, eflags,
preg->newline_anchor);
/* 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 (&input, match_first - input.raw_mbs_idx));
}
else
{
/* We apply translate/conversion manually, since it is trivial
in this case. */
/* 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) ? (unsigned char)string[match_first] : 0;
/* Apply translation if we need. */
ch = preg->translate ? preg->translate[ch] : ch;
/* In case of case insensitive mode, convert to upper case. */
ch = ((preg->syntax & RE_ICASE) && islower (ch)) ? toupper (ch) : ch;
}
/* Eliminate inappropriate one by fastmap. */
if (preg->can_be_null || fastmap == NULL || fastmap[ch])
{
/* Reconstruct the buffers so that the matcher can assume that
the matching starts from the begining of the buffer. */
re_string_reconstruct (&input, match_first, eflags,
preg->newline_anchor);
#ifdef RE_ENABLE_I18N
/* Eliminate it when it is a component of a multibyte character
and isn't the head of a multibyte character. */
if (MB_CUR_MAX == 1 || re_string_first_byte (&input, 0))
#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_bkref_len = 0;
match_last = check_matching (preg, &mctx, 0, fl_longest_match);
if (match_last != -1)
{
if (BE (match_last == -2, 0))
return REG_ESPACE;
else
break; /* We found a matching. */
}
}
}
/* Update counter. */
match_first += incr;
if (match_first < left_lim || right_lim < match_first)
break;
}
/* Set pmatch[] if we need. */
if (match_last != -1 && nmatch > 0)
{
int reg_idx;
/* Initialize registers. */
for (reg_idx = 0; 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;
mctx.match_last = pmatch[0].rm_eo = match_last;
if (!preg->no_sub && nmatch > 1)
{
/* We need the ranges of all the subexpressions. */
int halt_node;
re_dfastate_t *pstate = mctx.state_log[match_last];
#ifdef DEBUG
assert (mctx.state_log != NULL);
#endif
halt_node = check_halt_state_context (preg, pstate, &mctx,
match_last);
err = sift_states_backward (preg, &mctx, halt_node);
if (BE (err != REG_NOERROR, 0))
return err;
err = set_regs (preg, &mctx, nmatch, pmatch, halt_node);
if (BE (err != REG_NOERROR, 0))
return err;
}
/* At last, add the offset to the each registers, since we slided
the buffers so that We can assume that the matching starts from 0. */
for (reg_idx = 0; reg_idx < nmatch; ++reg_idx)
if (pmatch[reg_idx].rm_so != -1)
{
pmatch[reg_idx].rm_so += match_first;
pmatch[reg_idx].rm_eo += match_first;
}
}
re_free (mctx.state_log);
if (dfa->nbackref)
match_ctx_free (&mctx);
re_string_destruct (&input);
return (match_last == -1) ? REG_NOMATCH : REG_NOERROR;
}
/* 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 *
acquire_init_state_context (err, preg, mctx, idx)
reg_errcode_t *err;
const regex_t *preg;
const re_match_context_t *mctx;
int idx;
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
*err = REG_NOERROR;
if (dfa->init_state->has_constraint)
{
unsigned int context;
context = re_string_context_at (mctx->input, idx - 1, mctx->eflags,
preg->newline_anchor);
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_SEARCH means we must search where the matching starts,
FL_LONGEST_MATCH means we want the POSIX longest matching.
Note that the matcher assume that the maching starts from the current
index of the buffer. */
static int
check_matching (preg, mctx, fl_search, fl_longest_match)
const regex_t *preg;
re_match_context_t *mctx;
int fl_search, fl_longest_match;
{
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;
cur_state = acquire_init_state_context (&err, preg, mctx, cur_str_idx);
/* An initial state must not be NULL(invalid state). */
if (BE (cur_state == NULL, 0))
return -2;
if (mctx->state_log != NULL)
mctx->state_log[cur_str_idx] = cur_state;
/* If the RE accepts NULL string. */
if (cur_state->halt)
{
if (!cur_state->has_constraint
|| check_halt_state_context (preg, cur_state, mctx, 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))
{
cur_state = transit_state (&err, preg, mctx, cur_state,
fl_search && !match);
if (cur_state == NULL) /* Reached at the invalid state or an error. */
{
cur_str_idx = re_string_cur_idx (mctx->input);
if (BE (err != REG_NOERROR, 0))
return -2;
if (fl_search && !match)
{
/* Restart from initial state, since we are searching
the point from where matching start. */
#ifdef RE_ENABLE_I18N
if (MB_CUR_MAX == 1
|| re_string_first_byte (mctx->input, cur_str_idx))
#endif /* RE_ENABLE_I18N */
cur_state = acquire_init_state_context (&err, preg, mctx,
cur_str_idx);
if (BE (cur_state == NULL && err != REG_NOERROR, 0))
return -2;
if (mctx->state_log != NULL)
mctx->state_log[cur_str_idx] = cur_state;
}
else if (!fl_longest_match && match)
break;
else /* (fl_longest_match && match) || (!fl_search && !match) */
{
if (mctx->state_log == NULL)
break;
else
{
int max = mctx->state_log_top;
for (; cur_str_idx <= max; ++cur_str_idx)
if (mctx->state_log[cur_str_idx] != NULL)
break;
if (cur_str_idx > max)
break;
}
}
}
if (cur_state != NULL && cur_state->halt)
{
/* Reached at a halt state.
Check the halt state can satisfy the current context. */
if (!cur_state->has_constraint
|| check_halt_state_context (preg, cur_state, mctx,
re_string_cur_idx (mctx->input)))
{
/* We found an appropriate halt state. */
match_last = re_string_cur_idx (mctx->input);
match = 1;
if (!fl_longest_match)
break;
}
}
}
return match_last;
}
/* Check NODE match the current context. */
static int check_halt_node_context (dfa, node, context)
const re_dfa_t *dfa;
int node;
unsigned int context;
{
int entity;
re_token_type_t type = dfa->nodes[node].type;
if (type == END_OF_RE)
return 1;
if (type != OP_CONTEXT_NODE)
return 0;
entity = dfa->nodes[node].opr.ctx_info->entity;
if (dfa->nodes[entity].type != END_OF_RE
|| NOT_SATISFY_NEXT_CONSTRAINT (dfa->nodes[node].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
check_halt_state_context (preg, state, mctx, idx)
const regex_t *preg;
const re_dfastate_t *state;
const re_match_context_t *mctx;
int idx;
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
int i;
unsigned int context;
#ifdef DEBUG
assert (state->halt);
#endif
context = re_string_context_at (mctx->input, idx, mctx->eflags,
preg->newline_anchor);
for (i = 0; i < state->nodes.nelem; ++i)
if (check_halt_node_context (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
proceed_next_node (preg, mctx, pidx, node, eps_via_nodes)
const regex_t *preg;
const re_match_context_t *mctx;
int *pidx, node;
re_node_set *eps_via_nodes;
{
re_dfa_t *dfa = (re_dfa_t *)preg->buffer;
int i, err, dest_node, cur_entity;
dest_node = -1;
cur_entity = ((dfa->nodes[node].type == OP_CONTEXT_NODE)
? dfa->nodes[node].opr.ctx_info->entity : node);
if (IS_EPSILON_NODE (dfa->nodes[node].type))
{
int dest_entity = INT_MAX;
err = re_node_set_insert (eps_via_nodes, node);
if (BE (err < 0, 0))
return -1;
for (i = 0; i < mctx->state_log[*pidx]->nodes.nelem; ++i)
{
int candidate, candidate_entity;
candidate = mctx->state_log[*pidx]->nodes.elems[i];
candidate_entity = ((dfa->nodes[candidate].type == OP_CONTEXT_NODE)
? dfa->nodes[candidate].opr.ctx_info->entity
: candidate);
if (!re_node_set_contains (dfa->edests + node, candidate))
if (candidate == candidate_entity
|| !re_node_set_contains (dfa->edests + node, candidate_entity))
continue;
/* In order to avoid infinite loop like "(a*)*". */
if (cur_entity > candidate_entity
&& re_node_set_contains (eps_via_nodes, candidate))
continue;
if (dest_entity > candidate_entity)
{
dest_node = candidate;
dest_entity = candidate_entity;
}
}
#ifdef DEBUG
assert (dest_node != -1);
#endif
return dest_node;
}
else
{
int naccepted = 0, entity = node;
re_token_type_t type = dfa->nodes[node].type;
if (type == OP_CONTEXT_NODE)
{
entity = dfa->nodes[node].opr.ctx_info->entity;
type = dfa->nodes[entity].type;
}
#ifdef RE_ENABLE_I18N
if (ACCEPT_MB_NODE (type))
naccepted = check_node_accept_bytes (preg, entity, mctx->input, *pidx);
else
#endif /* RE_ENABLE_I18N */
if (type == OP_BACK_REF)
{
for (i = 0; i < mctx->nbkref_ents; ++i)
{
if (mctx->bkref_ents[i].node == node
&& mctx->bkref_ents[i].from == *pidx)
naccepted = mctx->bkref_ents[i].to - *pidx;
}
if (naccepted == 0)
{
err = re_node_set_insert (eps_via_nodes, node);
if (BE (err < 0, 0))
return -1;
dest_node = dfa->nexts[node];
if (re_node_set_contains (&mctx->state_log[*pidx]->nodes,
dest_node))
return dest_node;
for (i = 0; i < mctx->state_log[*pidx]->nodes.nelem; ++i)
{
dest_node = mctx->state_log[*pidx]->nodes.elems[i];
if ((dfa->nodes[dest_node].type == OP_CONTEXT_NODE
&& (dfa->nexts[node]
== dfa->nodes[dest_node].opr.ctx_info->entity)))
return dest_node;
}
}
}
if (naccepted != 0
|| check_node_accept (preg, dfa->nodes + node, mctx, *pidx))
{
dest_node = dfa->nexts[node];
*pidx = (naccepted == 0) ? *pidx + 1 : *pidx + naccepted;
#ifdef DEBUG
assert (mctx->state_log[*pidx] != NULL);
#endif
re_node_set_empty (eps_via_nodes);
return dest_node;
}
}
/* Must not reach here. */
#ifdef DEBUG
assert (0);
#endif
return 0;
}
/* 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 (i > 1). */
static reg_errcode_t
set_regs (preg, mctx, nmatch, pmatch, last_node)
const regex_t *preg;
const re_match_context_t *mctx;
size_t nmatch;
regmatch_t *pmatch;
int last_node;
{
re_dfa_t *dfa = (re_dfa_t *)preg->buffer;
int idx, cur_node, real_nmatch;
re_node_set eps_via_nodes;
#ifdef DEBUG
assert (nmatch > 1);
assert (mctx->state_log != NULL);
#endif
cur_node = dfa->init_node;
real_nmatch = (nmatch <= preg->re_nsub) ? nmatch : preg->re_nsub + 1;
re_node_set_init_empty (&eps_via_nodes);
for (idx = pmatch[0].rm_so; idx <= pmatch[0].rm_eo ;)
{
update_regs (dfa, pmatch, cur_node, idx, real_nmatch);
if (idx == pmatch[0].rm_eo && cur_node == last_node)
break;
/* Proceed to next node. */
cur_node = proceed_next_node (preg, mctx, &idx, cur_node, &eps_via_nodes);
if (BE (cur_node < 0, 0))
return REG_ESPACE;
}
re_node_set_free (&eps_via_nodes);
return REG_NOERROR;
}
static void
update_regs (dfa, pmatch, cur_node, cur_idx, nmatch)
re_dfa_t *dfa;
regmatch_t *pmatch;
int cur_node, cur_idx, nmatch;
{
int type = dfa->nodes[cur_node].type;
int reg_num;
if (type != OP_OPEN_SUBEXP && type != OP_CLOSE_SUBEXP)
return;
reg_num = dfa->nodes[cur_node].opr.idx + 1;
if (reg_num >= nmatch)
return;
if (type == OP_OPEN_SUBEXP)
{
/* We are at the first node of this sub expression. */
pmatch[reg_num].rm_so = cur_idx;
pmatch[reg_num].rm_eo = -1;
}
else if (type == OP_CLOSE_SUBEXP)
/* We are at the first node of this sub expression. */
pmatch[reg_num].rm_eo = cur_idx;
}
#define NUMBER_OF_STATE 1
/* This function checks the STATE_LOG from the MCTX->match_last 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
throwed away, we throw away the node `a'.
3. When 0 <= STR_IDX < n 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 throwed 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
sift_states_backward (preg, mctx, last_node)
const regex_t *preg;
const re_match_context_t *mctx;
int last_node;
{
reg_errcode_t err;
re_dfa_t *dfa = (re_dfa_t *)preg->buffer;
re_node_set state_buf;
int str_idx = mctx->match_last;
re_node_set *plog; /* Points the state_log[str_idx]->nodes */
#ifdef DEBUG
assert (mctx->state_log != NULL && mctx->state_log[str_idx] != NULL);
#endif
err = re_node_set_alloc (&state_buf, NUMBER_OF_STATE);
if (BE (err != REG_NOERROR, 0))
return err;
plog = &mctx->state_log[str_idx]->nodes;
/* 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_intersect (&state_buf, plog, dfa->inveclosures + last_node);
if (BE (err != REG_NOERROR, 0))
return err;
if (mctx->state_log[str_idx] != NULL
&& mctx->state_log[str_idx]->has_backref)
{
err = add_epsilon_backreference (dfa, mctx, plog, str_idx, &state_buf);
if (BE (err != REG_NOERROR, 0))
return err;
}
/* Update state log. */
mctx->state_log[str_idx] = re_acquire_state (&err, dfa, &state_buf);
if (BE (mctx->state_log[str_idx] == NULL && err != REG_NOERROR, 0))
return err;
/* Then check each states in the state_log. */
while (str_idx > 0)
{
int i, j;
/* Update counters. */
re_node_set_empty (&state_buf);
--str_idx;
plog = ((mctx->state_log[str_idx] == NULL) ? &empty_set
: &mctx->state_log[str_idx]->nodes);
/* Then build the next sifted state.
We build the next sifted state on `state_buf', and update
`state_log[str_idx]' with `state_buf'.
Note:
`state_buf' is the sifted state from `state_log[str_idx + 1]'.
`plog' points the node_set of the old `state_log[str_idx]'. */
for (i = 0; i < plog->nelem; i++)
{
int prev_node = plog->elems[i];
int entity = prev_node;
int naccepted = 0;
re_token_type_t type = dfa->nodes[prev_node].type;
if (type == OP_CONTEXT_NODE)
{
entity = dfa->nodes[prev_node].opr.ctx_info->entity;
type = dfa->nodes[entity].type;
}
#ifdef RE_ENABLE_I18N
/* If the node may accept `multi byte'. */
if (ACCEPT_MB_NODE (type))
naccepted = sift_states_iter_mb (preg, mctx, entity, str_idx,
mctx->match_last);
/* If the node is a back reference. */
else
#endif /* RE_ENABLE_I18N */
if (type == OP_BACK_REF)
for (j = 0; j < mctx->nbkref_ents; ++j)
{
naccepted = sift_states_iter_bkref (dfa, mctx->state_log,
mctx->bkref_ents + j,
prev_node, str_idx,
mctx->match_last);
if (naccepted)
break;
}
if (!naccepted
&& check_node_accept (preg, dfa->nodes + prev_node, mctx,
str_idx)
&& STATE_NODE_CONTAINS (mctx->state_log[str_idx + 1],
dfa->nexts[prev_node]))
naccepted = 1;
if (naccepted == 0)
continue;
/* `prev_node' may point the entity of the OP_CONTEXT_NODE,
then we use plog->elems[i] instead. */
err = re_node_set_add_intersect (&state_buf, plog,
dfa->inveclosures + prev_node);
if (BE (err != REG_NOERROR, 0))
return err;
}
if (mctx->state_log[str_idx] != NULL
&& mctx->state_log[str_idx]->has_backref)
{
err = add_epsilon_backreference (dfa, mctx, plog, str_idx, &state_buf);
if (BE (err != REG_NOERROR, 0))
return err;
}
/* Update state_log. */
mctx->state_log[str_idx] = re_acquire_state (&err, dfa, &state_buf);
if (BE (mctx->state_log[str_idx] == NULL && err != REG_NOERROR, 0))
return err;
}
re_node_set_free (&state_buf);
return REG_NOERROR;
}
/* Helper functions. */
static inline reg_errcode_t
clean_state_log_if_need (mctx, next_state_log_idx)
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;
}
#ifdef RE_ENABLE_I18N
static int
sift_states_iter_mb (preg, mctx, node_idx, str_idx, max_str_idx)
const regex_t *preg;
const re_match_context_t *mctx;
int node_idx, str_idx, max_str_idx;
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
int naccepted;
/* Check the node can accept `multi byte'. */
naccepted = check_node_accept_bytes (preg, node_idx, mctx->input, str_idx);
if (naccepted > 0 && str_idx + naccepted <= max_str_idx &&
!STATE_NODE_CONTAINS (mctx->state_log[str_idx + naccepted],
dfa->nexts[node_idx]))
/* The node can't accept the `multi byte', or the
destination was already throwed 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 */
static int
sift_states_iter_bkref (dfa, state_log, mctx_entry, node_idx, idx, match_last)
const re_dfa_t *dfa;
re_dfastate_t **state_log;
struct re_backref_cache_entry *mctx_entry;
int node_idx, idx, match_last;
{
int naccepted = 0;
int from_idx, to_idx;
from_idx = mctx_entry->from;
to_idx = mctx_entry->to;
if (mctx_entry->node == node_idx
&& from_idx == idx && to_idx <= match_last
&& STATE_NODE_CONTAINS (state_log[to_idx], dfa->nexts[node_idx]))
naccepted = to_idx - from_idx;
return naccepted;
}
static reg_errcode_t
add_epsilon_backreference (dfa, mctx, plog, idx, state_buf)
const re_dfa_t *dfa;
const re_match_context_t *mctx;
const re_node_set *plog;
int idx;
re_node_set *state_buf;
{
int i, j;
for (i = 0; i < plog->nelem; ++i)
{
int node_idx = plog->elems[i];
re_token_type_t type = dfa->nodes[node_idx].type;
if (type == OP_CONTEXT_NODE)
type = dfa->nodes[dfa->nodes[node_idx].opr.ctx_info->entity].type;
if (type == OP_BACK_REF &&
!re_node_set_contains (state_buf, node_idx))
{
for (j = 0; j < mctx->nbkref_ents; ++j)
{
struct re_backref_cache_entry *entry;
entry = mctx->bkref_ents + j;
if (entry->from == entry->to && entry->from == idx)
break;
}
if (j < mctx->nbkref_ents || idx == 0)
{
reg_errcode_t err;
err = re_node_set_add_intersect (state_buf, plog,
dfa->inveclosures + node_idx);
if (BE (err != REG_NOERROR, 0))
return err;
i = 0;
}
}
}
return REG_NOERROR;
}
/* 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 *
transit_state (err, preg, mctx, state, fl_search)
reg_errcode_t *err;
const regex_t *preg;
re_match_context_t *mctx;
re_dfastate_t *state;
int fl_search;
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
re_dfastate_t **trtable, *next_state;
unsigned char ch;
if (re_string_cur_idx (mctx->input) + 1 >= mctx->input->bufs_len
|| (re_string_cur_idx (mctx->input) + 1 >= mctx->input->valid_len
&& mctx->input->valid_len < mctx->input->len))
{
*err = extend_buffers (mctx);
if (BE (*err != REG_NOERROR, 0))
return NULL;
}
*err = REG_NOERROR;
if (state == NULL)
{
next_state = state;
re_string_skip_bytes (mctx->input, 1);
}
else
{
#ifdef RE_ENABLE_I18N
/* If the current state can accept multibyte. */
if (state->accept_mb)
{
*err = transit_state_mb (preg, state, mctx);
if (BE (*err != REG_NOERROR, 0))
return NULL;
}
#endif /* RE_ENABLE_I18N */
/* Then decide the next state with the single byte. */
if (1)
{
/* Use transition table */
ch = re_string_fetch_byte (mctx->input);
trtable = fl_search ? state->trtable_search : state->trtable;
if (trtable == NULL)
{
trtable = build_trtable (preg, state, fl_search);
if (fl_search)
state->trtable_search = trtable;
else
state->trtable = trtable;
}
next_state = trtable[ch];
}
else
{
/* don't use transition table */
next_state = transit_state_sb (err, preg, state, fl_search, mctx);
if (BE (next_state == NULL && err != REG_NOERROR, 0))
return NULL;
}
}
/* Update the state_log if we need. */
if (mctx->state_log != NULL)
{
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, preg->newline_anchor);
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 the next state has back references. */
if (next_state != NULL && next_state->has_backref)
{
*err = transit_state_bkref (preg, next_state, mctx);
if (BE (*err != REG_NOERROR, 0))
return NULL;
next_state = mctx->state_log[cur_idx];
}
}
return next_state;
}
/* Helper functions for transit_state. */
/* 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 (err, preg, state, fl_search, mctx)
reg_errcode_t *err;
const regex_t *preg;
re_dfastate_t *state;
int fl_search;
re_match_context_t *mctx;
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
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 (preg, dfa->nodes + cur_node, mctx, cur_str_idx))
{
*err = re_node_set_merge (&next_nodes,
dfa->eclosures + dfa->nexts[cur_node]);
if (BE (*err != REG_NOERROR, 0))
return NULL;
}
}
if (fl_search)
{
#ifdef RE_ENABLE_I18N
int not_initial = 0;
if (MB_CUR_MAX > 1)
for (node_cnt = 0; node_cnt < next_nodes.nelem; ++node_cnt)
if (dfa->nodes[next_nodes.elems[node_cnt]].type == CHARACTER)
{
not_initial = dfa->nodes[next_nodes.elems[node_cnt]].mb_partial;
break;
}
if (!not_initial)
#endif
{
*err = re_node_set_merge (&next_nodes,
dfa->init_state->entrance_nodes);
if (BE (*err != REG_NOERROR, 0))
return NULL;
}
}
context = re_string_context_at (mctx->input, cur_str_idx, mctx->eflags,
preg->newline_anchor);
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;
}
#ifdef RE_ENABLE_I18N
static reg_errcode_t
transit_state_mb (preg, pstate, mctx)
const regex_t *preg;
re_dfastate_t *pstate;
re_match_context_t *mctx;
{
reg_errcode_t err;
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
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 = 0, dest_idx;
unsigned int context;
re_dfastate_t *dest_state;
if (dfa->nodes[cur_node_idx].type == OP_CONTEXT_NODE)
{
context = re_string_context_at (mctx->input,
re_string_cur_idx (mctx->input),
mctx->eflags, preg->newline_anchor);
if (NOT_SATISFY_NEXT_CONSTRAINT (dfa->nodes[cur_node_idx].constraint,
context))
continue;
cur_node_idx = dfa->nodes[cur_node_idx].opr.ctx_info->entity;
}
/* How many bytes the node can accepts? */
if (ACCEPT_MB_NODE (dfa->nodes[cur_node_idx].type))
naccepted = check_node_accept_bytes (preg, 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;
err = clean_state_log_if_need (mctx, dest_idx);
if (BE (err != REG_NOERROR, 0))
return err;
#ifdef DEBUG
assert (dfa->nexts[cur_node_idx] != -1);
#endif
/* `cur_node_idx' may point the entity of the OP_CONTEXT_NODE,
then we use pstate->nodes.elems[i] instead. */
new_nodes = dfa->eclosures + dfa->nexts[pstate->nodes.elems[i]];
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,
preg->newline_anchor);
mctx->state_log[dest_idx]
= re_acquire_state_context (&err, dfa, &dest_nodes, context);
if (BE (mctx->state_log[dest_idx] == NULL && err != REG_NOERROR, 0))
return err;
if (dest_state != NULL)
re_node_set_free (&dest_nodes);
}
return REG_NOERROR;
}
#endif /* RE_ENABLE_I18N */
static reg_errcode_t
transit_state_bkref (preg, pstate, mctx)
const regex_t *preg;
re_dfastate_t *pstate;
re_match_context_t *mctx;
{
reg_errcode_t err;
re_dfastate_t **work_state_log;
work_state_log = re_malloc (re_dfastate_t *,
re_string_cur_idx (mctx->input) + 1);
if (BE (work_state_log == NULL, 0))
return REG_ESPACE;
err = transit_state_bkref_loop (preg, &pstate->nodes, work_state_log, mctx);
re_free (work_state_log);
return err;
}
/* Caller must allocate `work_state_log'. */
static reg_errcode_t
transit_state_bkref_loop (preg, nodes, work_state_log, mctx)
const regex_t *preg;
re_node_set *nodes;
re_dfastate_t **work_state_log;
re_match_context_t *mctx;
{
reg_errcode_t err;
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
int i, j;
re_dfastate_t **state_log_bak;
regmatch_t *cur_regs = re_malloc (regmatch_t, preg->re_nsub + 1);
int cur_str_idx = re_string_cur_idx (mctx->input);
if (BE (cur_regs == NULL, 0))
return REG_ESPACE;
for (i = 0; i < nodes->nelem; ++i)
{
unsigned char *buf;
int dest_str_idx, subexp_idx, prev_nelem, subexp_len;
int node_idx = nodes->elems[i];
unsigned int context;
re_token_t *node = dfa->nodes + node_idx;
re_dfastate_t *dest_state;
re_node_set *new_dest_nodes;
/* Check whether `node' is a backreference or not. */
if (node->type == OP_BACK_REF)
subexp_idx = node->opr.idx;
else if (node->type == OP_CONTEXT_NODE &&
dfa->nodes[node->opr.ctx_info->entity].type == OP_BACK_REF)
{
context = re_string_context_at (mctx->input, cur_str_idx,
mctx->eflags, preg->newline_anchor);
if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context))
continue;
subexp_idx = dfa->nodes[node->opr.ctx_info->entity].opr.idx;
}
else
continue;
/* `node' is a backreference.
At first, set registers to check the backreference. */
cur_regs[0].rm_so = 0;
cur_regs[0].rm_eo = cur_str_idx;
memcpy (work_state_log, mctx->state_log,
sizeof (re_dfastate_t *) * (cur_str_idx + 1));
mctx->match_last = cur_str_idx;
state_log_bak = mctx->state_log;
mctx->state_log = work_state_log;
sift_states_backward (preg, mctx, node_idx);
if (!STATE_NODE_CONTAINS (work_state_log[0], dfa->init_node))
continue;
for (j = 1; j <= preg->re_nsub; ++j)
cur_regs[j].rm_so = cur_regs[j].rm_eo = -1;
set_regs (preg, mctx, subexp_idx + 1, cur_regs, node_idx);
mctx->state_log = state_log_bak;
/* Then check that the backreference can match the input string. */
subexp_len = cur_regs[subexp_idx].rm_eo - cur_regs[subexp_idx].rm_so;
if (subexp_len < 0 || cur_str_idx + subexp_len > mctx->input->len)
continue;
if (cur_str_idx + subexp_len > 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;
}
buf = re_string_get_buffer (mctx->input);
if (strncmp (buf + cur_regs[subexp_idx].rm_so, buf + cur_str_idx,
subexp_len) != 0)
continue;
/* Successfully matched, add a new cache entry. */
dest_str_idx = cur_str_idx + subexp_len;
err = match_ctx_add_entry (mctx, node_idx, cur_str_idx, dest_str_idx);
if (BE (err != REG_NOERROR, 0))
return err;
err = clean_state_log_if_need (mctx, dest_str_idx);
if (BE (err != REG_NOERROR, 0))
return err;
/* 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
if (node->type == OP_CONTEXT_NODE && subexp_len == 0)
new_dest_nodes = dfa->nodes[node_idx].opr.ctx_info->bkref_eclosure;
else
new_dest_nodes = dfa->eclosures + dfa->nexts[node_idx];
context = (IS_WORD_CHAR (re_string_byte_at (mctx->input,
dest_str_idx - 1))
? CONTEXT_WORD : 0);
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))
return err;
}
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))
return err;
mctx->state_log[dest_str_idx]
= re_acquire_state_context (&err, dfa, &dest_nodes, context);
if (BE (mctx->state_log[dest_str_idx] == NULL
&& err != REG_NOERROR, 0))
return err;
re_node_set_free (&dest_nodes);
}
/* 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 = transit_state_bkref_loop (preg, new_dest_nodes, work_state_log,
mctx);
if (BE (err != REG_NOERROR, 0))
return err;
}
}
re_free (cur_regs);
return REG_NOERROR;
}
/* Build transition table for the state.
Return the new table if succeeded, otherwise return NULL. */
static re_dfastate_t **
build_trtable (preg, state, fl_search)
const regex_t *preg;
const re_dfastate_t *state;
int fl_search;
{
reg_errcode_t err;
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
int i, j, k, ch;
int ndests; /* Number of the destination states from `state'. */
re_dfastate_t **trtable, **dest_states, **dest_states_word, **dest_states_nl;
re_node_set follows, *dests_node;
bitset *dests_ch;
bitset acceptable;
/* 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. */
dests_node = re_malloc (re_node_set, SBC_MAX);
dests_ch = re_malloc (bitset, SBC_MAX);
/* Initialize transiton table. */
trtable = (re_dfastate_t **) calloc (sizeof (re_dfastate_t *), SBC_MAX);
if (BE (dests_node == NULL || dests_ch == NULL || trtable == NULL, 0))
return NULL;
/* At first, group all nodes belonging to `state' into several
destinations. */
ndests = group_nodes_into_DFAstates (preg, state, dests_node, dests_ch);
if (BE (ndests <= 0, 0))
{
re_free (dests_node);
re_free (dests_ch);
/* Return NULL in case of an error, trtable otherwise. */
return (ndests < 0) ? NULL : trtable;
}
dest_states = re_malloc (re_dfastate_t *, ndests);
dest_states_word = re_malloc (re_dfastate_t *, ndests);
dest_states_nl = re_malloc (re_dfastate_t *, ndests);
bitset_empty (acceptable);
err = re_node_set_alloc (&follows, ndests + 1);
if (BE (dest_states == NULL || dest_states_word == NULL
|| dest_states_nl == NULL || err != REG_NOERROR, 0))
return NULL;
/* 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))
return NULL;
}
}
/* If search flag is set, merge the initial state. */
if (fl_search)
{
#ifdef RE_ENABLE_I18N
int not_initial = 0;
for (j = 0; j < follows.nelem; ++j)
if (dfa->nodes[follows.elems[j]].type == CHARACTER)
{
not_initial = dfa->nodes[follows.elems[j]].mb_partial;
break;
}
if (!not_initial)
#endif
{
err = re_node_set_merge (&follows,
dfa->init_state->entrance_nodes);
if (BE (err != REG_NOERROR, 0))
return NULL;
}
}
dest_states[i] = re_acquire_state_context (&err, dfa, &follows, 0);
if (BE (dest_states[i] == NULL && err != REG_NOERROR, 0))
return NULL;
/* 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))
return NULL;
dest_states_nl[i] = re_acquire_state_context (&err, dfa, &follows,
CONTEXT_NEWLINE);
if (BE (dest_states_nl[i] == NULL && err != REG_NOERROR, 0))
return NULL;
}
else
{
dest_states_word[i] = dest_states[i];
dest_states_nl[i] = dest_states[i];
}
bitset_merge (acceptable, dests_ch[i]);
}
/* Update the transition table. */
for (i = 0, ch = 0; i < BITSET_UINTS; ++i)
for (j = 0; j < UINT_BITS; ++j, ++ch)
if ((acceptable[i] >> j) & 1)
{
if (IS_WORD_CHAR (ch))
{
for (k = 0; k < ndests; ++k)
if ((dests_ch[k][i] >> j) & 1)
trtable[ch] = dest_states_word[k];
}
else /* not WORD_CHAR */
{
for (k = 0; k < ndests; ++k)
if ((dests_ch[k][i] >> j) & 1)
trtable[ch] = dest_states[k];
}
}
/* new line */
for (k = 0; k < ndests; ++k)
if (bitset_contain (acceptable, NEWLINE_CHAR))
trtable[NEWLINE_CHAR] = dest_states_nl[k];
re_free (dest_states_nl);
re_free (dest_states_word);
re_free (dest_states);
re_node_set_free (&follows);
for (i = 0; i < ndests; ++i)
re_node_set_free (dests_node + i);
re_free (dests_ch);
re_free (dests_node);
return trtable;
}
/* 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
group_nodes_into_DFAstates (preg, state, dests_node, dests_ch)
const regex_t *preg;
const re_dfastate_t *state;
re_node_set *dests_node;
bitset *dests_ch;
{
reg_errcode_t err;
const re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
int i, j, k;
int ndests; /* Number of the destinations from `state'. */
bitset 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)
{
unsigned int constraint = 0;
re_token_t *node = &dfa->nodes[cur_nodes->elems[i]];
re_token_type_t type = node->type;
if (type == OP_CONTEXT_NODE)
{
constraint = node->constraint;
node = dfa->nodes + node->opr.ctx_info->entity;
type = node->type;
}
/* 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)
{
bitset_set_all (accepts);
if (!(preg->syntax & RE_DOT_NEWLINE))
bitset_clear (accepts, '\n');
if (preg->syntax & RE_DOT_NOT_NULL)
bitset_clear (accepts, '\0');
}
else
continue;
/* Check the `accepts' and sift the characters which are not
match it the context. */
if (constraint)
{
if (constraint & NEXT_WORD_CONSTRAINT)
for (j = 0; j < BITSET_UINTS; ++j)
accepts[j] &= dfa->word_char[j];
else if (constraint & NEXT_NOTWORD_CONSTRAINT)
for (j = 0; j < BITSET_UINTS; ++j)
accepts[j] &= ~dfa->word_char[j];
else if (constraint & NEXT_NEWLINE_CONSTRAINT)
{
int accepts_newline = bitset_contain (accepts, NEWLINE_CHAR);
bitset_empty (accepts);
if (accepts_newline)
bitset_set (accepts, NEWLINE_CHAR);
else
continue;
}
}
/* Then divide `accepts' into DFA states, or create a new
state. */
for (j = 0; j < ndests; ++j)
{
bitset intersec; /* Intersection sets, see below. */
bitset remains;
/* Flags, see below. */
int 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_UINTS; ++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_UINTS; ++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))
return -1;
++ndests;
}
/* Put the position in the current group. */
err = re_node_set_insert (&dests_node[j], cur_nodes->elems[i]);
if (BE (err < 0, 0))
return -1;
/* 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))
return -1;
++ndests;
bitset_empty (accepts);
}
}
return ndests;
}
#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
check_node_accept_bytes (preg, node_idx, input, str_idx)
const regex_t *preg;
int node_idx, str_idx;
const re_string_t *input;
{
const re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
const re_token_t *node = dfa->nodes + node_idx;
int elem_len = re_string_elem_size_at (input, str_idx);
int char_len = re_string_char_size_at (input, str_idx);
int i;
# ifdef _LIBC
int j;
uint32_t nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
# endif /* _LIBC */
if (elem_len <= 1 && char_len <= 1)
return 0;
if (node->type == OP_PERIOD)
{
/* '.' accepts any one character except the following two cases. */
if ((!(preg->syntax & RE_DOT_NEWLINE) &&
re_string_byte_at (input, str_idx) == '\n') ||
((preg->syntax & RE_DOT_NOT_NULL) &&
re_string_byte_at (input, str_idx) == '\0'))
return 0;
return char_len;
}
else if (node->type == COMPLEX_BRACKET)
{
const re_charset_t *cset = node->opr.mbcset;
# ifdef _LIBC
const unsigned char *pin = re_string_get_buffer (input) + str_idx;
# 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
if (nrules != 0)
{
unsigned int in_collseq = 0;
const int32_t *table, *indirect;
const unsigned char *weights, *extra, *collseqwc;
int32_t idx;
/* 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);
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];
if (weight_len == weights[equiv_class_idx])
{
int cnt = 0;
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? */
wchar_t cmp_buf[6] = {L'\0', L'\0', wc, L'\0', L'\0', L'\0'};
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
find_collation_sequence_value (mbs, mbs_len)
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);
for (idx = 0; ;)
{
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);
}
}
}
# endif /* _LIBC */
#endif /* RE_ENABLE_I18N */
/* Check whether the node accepts the byte which is IDX-th
byte of the INPUT. */
static int
check_node_accept (preg, node, mctx, idx)
const regex_t *preg;
const re_token_t *node;
const re_match_context_t *mctx;
int idx;
{
const re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
const re_token_t *cur_node;
unsigned char ch;
if (node->type == OP_CONTEXT_NODE)
{
/* The node has constraints. Check whether the current context
satisfies the constraints. */
unsigned int context = re_string_context_at (mctx->input, idx,
mctx->eflags,
preg->newline_anchor);
if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context))
return 0;
cur_node = dfa->nodes + node->opr.ctx_info->entity;
}
else
cur_node = node;
ch = re_string_byte_at (mctx->input, idx);
if (cur_node->type == CHARACTER)
return cur_node->opr.c == ch;
else if (cur_node->type == SIMPLE_BRACKET)
return bitset_contain (cur_node->opr.sbcset, ch);
else if (cur_node->type == OP_PERIOD)
return !((ch == '\n' && !(preg->syntax & RE_DOT_NEWLINE))
|| (ch == '\0' && (preg->syntax & RE_DOT_NOT_NULL)));
else
return 0;
}
/* Extend the buffers, if the buffers have run out. */
static reg_errcode_t
extend_buffers (mctx)
re_match_context_t *mctx;
{
reg_errcode_t ret;
re_string_t *pstr = mctx->input;
/* 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. */
mctx->state_log = re_realloc (mctx->state_log, re_dfastate_t *,
pstr->bufs_len * 2);
if (BE (mctx->state_log == NULL, 0))
return REG_ESPACE;
}
/* Then reconstruct the buffers. */
if (pstr->icase)
{
#ifdef RE_ENABLE_I18N
if (MB_CUR_MAX > 1)
build_wcs_upper_buffer (pstr);
else
#endif /* RE_ENABLE_I18N */
build_upper_buffer (pstr);
}
else
{
#ifdef RE_ENABLE_I18N
if (MB_CUR_MAX > 1)
build_wcs_buffer (pstr);
else
#endif /* RE_ENABLE_I18N */
{
if (pstr->trans != NULL)
re_string_translate_buffer (pstr);
else
pstr->valid_len = pstr->bufs_len;
}
}
return REG_NOERROR;
}
/* Functions for matching context. */
static reg_errcode_t
match_ctx_init (mctx, eflags, input, n)
re_match_context_t *mctx;
int eflags, n;
re_string_t *input;
{
mctx->eflags = eflags;
mctx->input = input;
mctx->match_last = -1;
if (n > 0)
{
mctx->bkref_ents = re_malloc (struct re_backref_cache_entry, n);
if (BE (mctx->bkref_ents == NULL, 0))
return REG_ESPACE;
}
else
mctx->bkref_ents = NULL;
mctx->nbkref_ents = 0;
mctx->abkref_ents = n;
mctx->max_bkref_len = 0;
return REG_NOERROR;
}
static void
match_ctx_free (mctx)
re_match_context_t *mctx;
{
re_free (mctx->bkref_ents);
}
/* Add a new backreference entry to the cache. */
static reg_errcode_t
match_ctx_add_entry (mctx, node, from, to)
re_match_context_t *mctx;
int node, from, to;
{
if (mctx->nbkref_ents >= mctx->abkref_ents)
{
mctx->bkref_ents = re_realloc (mctx->bkref_ents,
struct re_backref_cache_entry,
mctx->abkref_ents * 2);
if (BE (mctx->bkref_ents == NULL, 0))
return REG_ESPACE;
memset (mctx->bkref_ents + mctx->nbkref_ents, '\0',
sizeof (struct re_backref_cache_entry) * mctx->abkref_ents);
mctx->abkref_ents *= 2;
}
mctx->bkref_ents[mctx->nbkref_ents].node = node;
mctx->bkref_ents[mctx->nbkref_ents].from = from;
mctx->bkref_ents[mctx->nbkref_ents++].to = to;
if (mctx->max_bkref_len < to - from)
mctx->max_bkref_len = to - from;
return REG_NOERROR;
}
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