int
research(Regexp *rp, register char *str, int start,
register size_t len, int need_start)
{
char *ret = str;
int try_backref;
/*
* Always do dfa search if can; if it fails, then even if
* need_start is true, we won't bother with the regex search.
*/
if (rp->dfa) {
char save;
int count = 0;
/*
* dfa likes to stick a '\n' right after the matched
* text. So we just save and restore the character.
*/
save = str[start+len];
ret = dfaexec(&(rp->dfareg), str+start, str+start+len, TRUE,
&count, &try_backref);
str[start+len] = save;
}
if (ret) {
if (need_start || rp->dfa == FALSE || try_backref) {
int res = re_search(&(rp->pat), str, start+len,
start, len, &(rp->regs));
return res;
} else
return 1;
} else
return -1;
}
int
main (int argc, char **argv)
{
struct dfa *dfa;
char *beg, *end, *p;
int allow_nl;
set_program_name (argv[0]);
if (argc < 3)
exit (EXIT_FAILURE);
setlocale (LC_ALL, "");
dfasyntax (RE_SYNTAX_GREP | RE_NO_EMPTY_RANGES, 0, '\n');
dfa = dfaalloc ();
dfacomp (argv[1], strlen (argv[1]), dfa, 0);
beg = argv[2];
end = argv[2] + strlen (argv[2]);
allow_nl = argc > 3 && atoi (argv[3]);
p = dfaexec (dfa, beg, end, allow_nl, NULL, NULL);
if (p != NULL)
printf ("%zd\n", p - beg);
exit (EXIT_SUCCESS);
}
int evaluate_fast_regex( struct fast_regex * fre_t, char * str, size_t len )
{
char * sub ;
struct _fregex * fre = (struct _fregex *)( fre_t->data ) ;
if( fre->kwset )
{
struct kwsmatch kwsm ;
sub = kwsexec( fre->kwset, (char *)str, len, &kwsm) ;
if( sub == NULL )
return 0 ;
if( kwsm.index < fre->num_exact_kws )
{
return 1 ;
}
}
if( HAS_DFA(fre_t->options) )
{
int backref = 0 ;
sub = dfaexec( &(fre->dfa), str, (str+len), 0, NULL, &backref) ;
if( sub == NULL )
return 0 ;
if ( !backref || (fre_t->options & FRE_NO_REGEX) )
return 1 ;
}
return re_match( &fre->regex , str, len, 0, NULL ) > 0 ;
}
int
research(Regexp *rp, register char *str, int start,
register size_t len, int flags)
{
const char *ret = str;
int try_backref;
int need_start;
int no_bol;
int res;
need_start = ((flags & RE_NEED_START) != 0);
no_bol = ((flags & RE_NO_BOL) != 0);
if (no_bol)
rp->pat.not_bol = 1;
/*
* Always do dfa search if can; if it fails, then even if
* need_start is true, we won't bother with the regex search.
*
* The dfa matcher doesn't have a no_bol flag, so don't bother
* trying it in that case.
*/
if (rp->dfa && ! no_bol) {
char save;
int count = 0;
/*
* dfa likes to stick a '\n' right after the matched
* text. So we just save and restore the character.
*/
save = str[start+len];
ret = dfaexec(&(rp->dfareg), str+start, str+start+len, TRUE,
&count, &try_backref);
str[start+len] = save;
}
if (ret) {
if (need_start || rp->dfa == FALSE || try_backref) {
/*
* Passing NULL as last arg speeds up search for cases
* where we don't need the start/end info.
*/
res = re_search(&(rp->pat), str, start+len,
start, len, need_start ? &(rp->regs) : NULL);
} else
res = 1;
} else
res = -1;
rp->pat.not_bol = 0;
return res;
}
size_t
EGexecute (char const *buf, size_t size, size_t *match_size,
char const *start_ptr)
{
char const *buflim, *beg, *end, *match, *best_match, *mb_start;
char eol = eolbyte;
int backref;
regoff_t start;
size_t len, best_len;
struct kwsmatch kwsm;
size_t i, ret_val;
mb_len_map_t *map = NULL;
if (MB_CUR_MAX > 1)
{
if (match_icase)
{
/* mbtolower adds a NUL byte at the end. That will provide
space for the sentinel byte dfaexec may add. */
char *case_buf = mbtolower (buf, &size, &map);
if (start_ptr)
start_ptr = case_buf + (start_ptr - buf);
buf = case_buf;
}
}
mb_start = buf;
buflim = buf + size;
for (beg = end = buf; end < buflim; beg = end)
{
if (!start_ptr)
{
/* We don't care about an exact match. */
if (kwset)
{
/* Find a possible match using the KWset matcher. */
size_t offset = kwsexec (kwset, beg, buflim - beg, &kwsm);
if (offset == (size_t) -1)
goto failure;
beg += offset;
/* Narrow down to the line containing the candidate, and
run it through DFA. */
if ((end = memchr(beg, eol, buflim - beg)) != NULL)
end++;
else
end = buflim;
match = beg;
while (beg > buf && beg[-1] != eol)
--beg;
if (kwsm.index < kwset_exact_matches)
{
if (!MBS_SUPPORT)
goto success;
if (mb_start < beg)
mb_start = beg;
if (MB_CUR_MAX == 1
|| !is_mb_middle (&mb_start, match, buflim,
kwsm.size[0]))
goto success;
}
if (dfaexec (dfa, beg, (char *) end, 0, NULL, &backref) == NULL)
continue;
}
else
{
/* No good fixed strings; start with DFA. */
char const *next_beg = dfaexec (dfa, beg, (char *) buflim,
0, NULL, &backref);
/* If there's no match, or if we've matched the sentinel,
we're done. */
if (next_beg == NULL || next_beg == buflim)
break;
/* Narrow down to the line we've found. */
beg = next_beg;
if ((end = memchr(beg, eol, buflim - beg)) != NULL)
end++;
else
end = buflim;
while (beg > buf && beg[-1] != eol)
--beg;
}
/* Successful, no backreferences encountered! */
if (!backref)
goto success;
}
else
{
/* We are looking for the leftmost (then longest) exact match.
We will go through the outer loop only once. */
beg = start_ptr;
end = buflim;
}
/* If the "line" is longer than the maximum regexp offset,
die as if we've run out of memory. */
if (TYPE_MAXIMUM (regoff_t) < end - buf - 1)
xalloc_die ();
/* If we've made it to this point, this means DFA has seen
a probable match, and we need to run it through Regex. */
best_match = end;
best_len = 0;
for (i = 0; i < pcount; i++)
{
patterns[i].regexbuf.not_eol = 0;
start = re_search (&(patterns[i].regexbuf),
buf, end - buf - 1,
beg - buf, end - beg - 1,
&(patterns[i].regs));
if (start < -1)
xalloc_die ();
else if (0 <= start)
{
len = patterns[i].regs.end[0] - start;
match = buf + start;
if (match > best_match)
continue;
if (start_ptr && !match_words)
goto assess_pattern_match;
if ((!match_lines && !match_words)
|| (match_lines && len == end - beg - 1))
{
match = beg;
len = end - beg;
goto assess_pattern_match;
}
/* If -w, check if the match aligns with word boundaries.
We do this iteratively because:
(a) the line may contain more than one occurrence of the
pattern, and
(b) Several alternatives in the pattern might be valid at a
given point, and we may need to consider a shorter one to
find a word boundary. */
if (match_words)
while (match <= best_match)
{
regoff_t shorter_len = 0;
if ((match == buf || !WCHAR ((unsigned char) match[-1]))
&& (start + len == end - buf - 1
|| !WCHAR ((unsigned char) match[len])))
goto assess_pattern_match;
if (len > 0)
{
/* Try a shorter length anchored at the same place. */
--len;
patterns[i].regexbuf.not_eol = 1;
shorter_len = re_match (&(patterns[i].regexbuf),
buf, match + len - beg,
match - buf,
&(patterns[i].regs));
if (shorter_len < -1)
xalloc_die ();
}
if (0 < shorter_len)
len = shorter_len;
else
{
/* Try looking further on. */
if (match == end - 1)
break;
match++;
patterns[i].regexbuf.not_eol = 0;
start = re_search (&(patterns[i].regexbuf),
buf, end - buf - 1,
match - buf, end - match - 1,
&(patterns[i].regs));
if (start < 0)
{
if (start < -1)
xalloc_die ();
break;
}
len = patterns[i].regs.end[0] - start;
match = buf + start;
}
} /* while (match <= best_match) */
continue;
assess_pattern_match:
if (!start_ptr)
{
/* Good enough for a non-exact match.
No need to look at further patterns, if any. */
goto success;
}
if (match < best_match || (match == best_match && len > best_len))
{
/* Best exact match: leftmost, then longest. */
best_match = match;
best_len = len;
}
} /* if re_search >= 0 */
} /* for Regex patterns. */
if (best_match < end)
{
/* We have found an exact match. We were just
waiting for the best one (leftmost then longest). */
beg = best_match;
len = best_len;
goto success_in_len;
}
} /* for (beg = end ..) */
failure:
ret_val = -1;
goto out;
success:
len = end - beg;
success_in_len:;
size_t off = beg - buf;
mb_case_map_apply (map, &off, &len);
*match_size = len;
ret_val = off;
out:
return ret_val;
}
static size_t
EGexecute (const void *compiled_pattern,
const char *buf, size_t buf_size,
size_t *match_size, bool exact)
{
struct compiled_regex *cregex = (struct compiled_regex *) compiled_pattern;
register const char *buflim, *beg, *end;
char eol = cregex->eolbyte;
int backref, start, len;
struct kwsmatch kwsm;
size_t i;
#ifdef MBS_SUPPORT
char *mb_properties = NULL;
#endif /* MBS_SUPPORT */
#ifdef MBS_SUPPORT
if (MB_CUR_MAX > 1 && cregex->ckwset.kwset)
mb_properties = check_multibyte_string (buf, buf_size);
#endif /* MBS_SUPPORT */
buflim = buf + buf_size;
for (beg = end = buf; end < buflim; beg = end)
{
if (!exact)
{
if (cregex->ckwset.kwset)
{
/* Find a possible match using the KWset matcher. */
size_t offset = kwsexec (cregex->ckwset.kwset, beg, buflim - beg, &kwsm);
if (offset == (size_t) -1)
{
#ifdef MBS_SUPPORT
if (MB_CUR_MAX > 1)
free (mb_properties);
#endif
return (size_t)-1;
}
beg += offset;
/* Narrow down to the line containing the candidate, and
run it through DFA. */
end = memchr (beg, eol, buflim - beg);
if (end != NULL)
end++;
else
end = buflim;
#ifdef MBS_SUPPORT
if (MB_CUR_MAX > 1 && mb_properties[beg - buf] == 0)
continue;
#endif
while (beg > buf && beg[-1] != eol)
--beg;
if (kwsm.index < cregex->kwset_exact_matches)
goto success;
if (dfaexec (&cregex->dfa, beg, end - beg, &backref) == (size_t) -1)
continue;
}
else
{
/* No good fixed strings; start with DFA. */
size_t offset = dfaexec (&cregex->dfa, beg, buflim - beg, &backref);
if (offset == (size_t) -1)
break;
/* Narrow down to the line we've found. */
beg += offset;
end = memchr (beg, eol, buflim - beg);
if (end != NULL)
end++;
else
end = buflim;
while (beg > buf && beg[-1] != eol)
--beg;
}
/* Successful, no backreferences encountered! */
if (!backref)
goto success;
}
else
end = beg + buf_size;
/* If we've made it to this point, this means DFA has seen
a probable match, and we need to run it through Regex. */
for (i = 0; i < cregex->pcount; i++)
{
cregex->patterns[i].regexbuf.not_eol = 0;
if (0 <= (start = re_search (&(cregex->patterns[i].regexbuf), beg,
end - beg - 1, 0,
end - beg - 1, &(cregex->patterns[i].regs))))
{
len = cregex->patterns[i].regs.end[0] - start;
if (exact)
{
*match_size = len;
return start;
}
if ((!cregex->match_lines && !cregex->match_words)
|| (cregex->match_lines && len == end - beg - 1))
goto success;
/* If -w, check if the match aligns with word boundaries.
We do this iteratively because:
(a) the line may contain more than one occurence of the
pattern, and
(b) Several alternatives in the pattern might be valid at a
given point, and we may need to consider a shorter one to
find a word boundary. */
if (cregex->match_words)
while (start >= 0)
{
if ((start == 0 || !IS_WORD_CONSTITUENT ((unsigned char) beg[start - 1]))
&& (len == end - beg - 1
|| !IS_WORD_CONSTITUENT ((unsigned char) beg[start + len])))
goto success;
if (len > 0)
{
/* Try a shorter length anchored at the same place. */
--len;
cregex->patterns[i].regexbuf.not_eol = 1;
len = re_match (&(cregex->patterns[i].regexbuf), beg,
start + len, start,
&(cregex->patterns[i].regs));
}
if (len <= 0)
{
/* Try looking further on. */
if (start == end - beg - 1)
break;
++start;
cregex->patterns[i].regexbuf.not_eol = 0;
start = re_search (&(cregex->patterns[i].regexbuf), beg,
end - beg - 1,
start, end - beg - 1 - start,
&(cregex->patterns[i].regs));
len = cregex->patterns[i].regs.end[0] - start;
}
}
}
} /* for Regex patterns. */
} /* for (beg = end ..) */
#ifdef MBS_SUPPORT
if (MB_CUR_MAX > 1 && mb_properties)
free (mb_properties);
#endif /* MBS_SUPPORT */
return (size_t) -1;
success:
#ifdef MBS_SUPPORT
if (MB_CUR_MAX > 1 && mb_properties)
free (mb_properties);
#endif /* MBS_SUPPORT */
*match_size = end - beg;
return beg - buf;
}
int
match_regex (struct regex *regex, char *buf, size_t buflen,
size_t buf_start_offset, struct re_registers *regarray,
int regsize)
{
int ret;
static struct regex *regex_last;
/* printf ("Matching from %d/%d\n", buf_start_offset, buflen); */
/* Keep track of the last regexp matched. */
if (!regex)
{
regex = regex_last;
if (!regex_last)
bad_prog (_(NO_REGEX));
}
else
regex_last = regex;
/* gnulib's re_search uses signed-int as length */
if (buflen >= INT_MAX)
panic (_("regex input buffer length larger than INT_MAX"));
if (regex->pattern.no_sub && regsize)
{
/* Re-compiling an existing regex, free the previously allocated
structures. */
if (regex->dfa)
{
dfafree (regex->dfa);
free (regex->dfa);
regex->dfa = NULL;
}
regfree (®ex->pattern);
compile_regex_1 (regex, regsize);
}
regex->pattern.regs_allocated = REGS_REALLOCATE;
/* Optimized handling for '^' and '$' patterns */
if (regex->begline || regex->endline)
{
size_t offset;
if (regex->endline)
{
const char *p = NULL;
if (regex->flags & REG_NEWLINE)
p = memchr (buf + buf_start_offset, buffer_delimiter,
buflen - buf_start_offset);
offset = p ? p - buf : buflen;
}
else if (buf_start_offset == 0)
/* begline anchor, starting at beginning of the buffer. */
offset = 0;
else if (!(regex->flags & REG_NEWLINE))
/* begline anchor, starting in the middle of the text buffer,
and multiline regex is not specified - will never match.
Example: seq 2 | sed 'N;s/^/X/g' */
return 0;
else if (buf[buf_start_offset - 1] == buffer_delimiter)
/* begline anchor, starting in the middle of the text buffer,
with multiline match, and the current character
is the line delimiter - start here.
Example: seq 2 | sed 'N;s/^/X/mg' */
offset = buf_start_offset;
else
{
/* begline anchor, starting in the middle of the search buffer,
all previous optimizions didn't work: search
for the next line delimiter character in the buffer,
and start from there if found. */
const char *p = memchr (buf + buf_start_offset, buffer_delimiter,
buflen - buf_start_offset);
if (p == NULL)
return 0;
offset = p - buf + 1;
}
if (regsize)
{
size_t i;
if (!regarray->start)
{
regarray->start = XCALLOC (1, regoff_t);
regarray->end = XCALLOC (1, regoff_t);
regarray->num_regs = 1;
}
regarray->start[0] = offset;
regarray->end[0] = offset;
for (i = 1 ; i < regarray->num_regs; ++i)
regarray->start[i] = regarray->end[i] = -1;
}
return 1;
}
if (buf_start_offset == 0)
{
struct dfa *superset = dfasuperset (regex->dfa);
if (superset && !dfaexec (superset, buf, buf + buflen, true, NULL, NULL))
return 0;
if ((!regsize && (regex->flags & REG_NEWLINE))
|| (!superset && dfaisfast (regex->dfa)))
{
bool backref = false;
if (!dfaexec (regex->dfa, buf, buf + buflen, true, NULL, &backref))
return 0;
if (!regsize && (regex->flags & REG_NEWLINE) && !backref)
return 1;
}
}
/* If the buffer delimiter is not newline character, we cannot use
newline_anchor flag of regex. So do it line-by-line, and add offset
value to results. */
if ((regex->flags & REG_NEWLINE) && buffer_delimiter != '\n')
{
const char *beg, *end;
const char *start;
beg = buf;
if (buf_start_offset > 0)
{
const char *eol = memrchr (buf, buffer_delimiter, buf_start_offset);
if (eol != NULL)
beg = eol + 1;
}
start = buf + buf_start_offset;
for (;;)
{
end = memchr (beg, buffer_delimiter, buf + buflen - beg);
if (end == NULL)
end = buf + buflen;
ret = re_search (®ex->pattern, beg, end - beg,
start - beg, end - start,
regsize ? regarray : NULL);
if (ret > -1)
{
size_t i;
ret += beg - buf;
if (regsize)
{
for (i = 0; i < regarray->num_regs; ++i)
{
if (regarray->start[i] > -1)
regarray->start[i] += beg - buf;
if (regarray->end[i] > -1)
regarray->end[i] += beg - buf;
}
}
break;
}
if (end == buf + buflen)
break;
beg = start = end + 1;
}
}
else
ret = re_search (®ex->pattern, buf, buflen, buf_start_offset,
buflen - buf_start_offset,
regsize ? regarray : NULL);
return (ret > -1);
}
