1916 lines
55 KiB
C
1916 lines
55 KiB
C
/*************************************************
|
|
* Perl-Compatible Regular Expressions *
|
|
*************************************************/
|
|
|
|
/* PCRE is a library of functions to support regular expressions whose syntax
|
|
and semantics are as close as possible to those of the Perl 5 language.
|
|
|
|
Written by Philip Hazel
|
|
Original API code Copyright (c) 1997-2012 University of Cambridge
|
|
New API code Copyright (c) 2016-2023 University of Cambridge
|
|
|
|
-----------------------------------------------------------------------------
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions are met:
|
|
|
|
* Redistributions of source code must retain the above copyright notice,
|
|
this list of conditions and the following disclaimer.
|
|
|
|
* Redistributions in binary form must reproduce the above copyright
|
|
notice, this list of conditions and the following disclaimer in the
|
|
documentation and/or other materials provided with the distribution.
|
|
|
|
* Neither the name of the University of Cambridge nor the names of its
|
|
contributors may be used to endorse or promote products derived from
|
|
this software without specific prior written permission.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
POSSIBILITY OF SUCH DAMAGE.
|
|
-----------------------------------------------------------------------------
|
|
*/
|
|
|
|
/* This module contains functions for scanning a compiled pattern and
|
|
collecting data (e.g. minimum matching length). */
|
|
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include "config.h"
|
|
#endif
|
|
|
|
#include "pcre2_internal.h"
|
|
|
|
/* The maximum remembered capturing brackets minimum. */
|
|
|
|
#define MAX_CACHE_BACKREF 128
|
|
|
|
/* Set a bit in the starting code unit bit map. */
|
|
|
|
#define SET_BIT(c) re->start_bitmap[(c)/8] |= (1u << ((c)&7))
|
|
|
|
/* Returns from set_start_bits() */
|
|
|
|
enum { SSB_FAIL, SSB_DONE, SSB_CONTINUE, SSB_UNKNOWN, SSB_TOODEEP };
|
|
|
|
|
|
/*************************************************
|
|
* Find the minimum subject length for a group *
|
|
*************************************************/
|
|
|
|
/* Scan a parenthesized group and compute the minimum length of subject that
|
|
is needed to match it. This is a lower bound; it does not mean there is a
|
|
string of that length that matches. In UTF mode, the result is in characters
|
|
rather than code units. The field in a compiled pattern for storing the minimum
|
|
length is 16-bits long (on the grounds that anything longer than that is
|
|
pathological), so we give up when we reach that amount. This also means that
|
|
integer overflow for really crazy patterns cannot happen.
|
|
|
|
Backreference minimum lengths are cached to speed up multiple references. This
|
|
function is called only when the highest back reference in the pattern is less
|
|
than or equal to MAX_CACHE_BACKREF, which is one less than the size of the
|
|
caching vector. The zeroth element contains the number of the highest set
|
|
value.
|
|
|
|
Arguments:
|
|
re compiled pattern block
|
|
code pointer to start of group (the bracket)
|
|
startcode pointer to start of the whole pattern's code
|
|
utf UTF flag
|
|
recurses chain of recurse_check to catch mutual recursion
|
|
countptr pointer to call count (to catch over complexity)
|
|
backref_cache vector for caching back references.
|
|
|
|
This function is no longer called when the pattern contains (*ACCEPT); however,
|
|
the old code for returning -1 is retained, just in case.
|
|
|
|
Returns: the minimum length
|
|
-1 \C in UTF-8 mode
|
|
or (*ACCEPT)
|
|
or pattern too complicated
|
|
-2 internal error (missing capturing bracket)
|
|
-3 internal error (opcode not listed)
|
|
*/
|
|
|
|
static int
|
|
find_minlength(const pcre2_real_code *re, PCRE2_SPTR code,
|
|
PCRE2_SPTR startcode, BOOL utf, recurse_check *recurses, int *countptr,
|
|
int *backref_cache)
|
|
{
|
|
int length = -1;
|
|
int branchlength = 0;
|
|
int prev_cap_recno = -1;
|
|
int prev_cap_d = 0;
|
|
int prev_recurse_recno = -1;
|
|
int prev_recurse_d = 0;
|
|
uint32_t once_fudge = 0;
|
|
BOOL had_recurse = FALSE;
|
|
BOOL dupcapused = (re->flags & PCRE2_DUPCAPUSED) != 0;
|
|
PCRE2_SPTR nextbranch = code + GET(code, 1);
|
|
PCRE2_UCHAR *cc = (PCRE2_UCHAR *)code + 1 + LINK_SIZE;
|
|
recurse_check this_recurse;
|
|
|
|
/* If this is a "could be empty" group, its minimum length is 0. */
|
|
|
|
if (*code >= OP_SBRA && *code <= OP_SCOND) return 0;
|
|
|
|
/* Skip over capturing bracket number */
|
|
|
|
if (*code == OP_CBRA || *code == OP_CBRAPOS) cc += IMM2_SIZE;
|
|
|
|
/* A large and/or complex regex can take too long to process. */
|
|
|
|
if ((*countptr)++ > 1000) return -1;
|
|
|
|
/* Scan along the opcodes for this branch. If we get to the end of the branch,
|
|
check the length against that of the other branches. If the accumulated length
|
|
passes 16-bits, reset to that value and skip the rest of the branch. */
|
|
|
|
for (;;)
|
|
{
|
|
int d, min, recno;
|
|
PCRE2_UCHAR op, *cs, *ce;
|
|
|
|
if (branchlength >= UINT16_MAX)
|
|
{
|
|
branchlength = UINT16_MAX;
|
|
cc = (PCRE2_UCHAR *)nextbranch;
|
|
}
|
|
|
|
op = *cc;
|
|
switch (op)
|
|
{
|
|
case OP_COND:
|
|
case OP_SCOND:
|
|
|
|
/* If there is only one branch in a condition, the implied branch has zero
|
|
length, so we don't add anything. This covers the DEFINE "condition"
|
|
automatically. If there are two branches we can treat it the same as any
|
|
other non-capturing subpattern. */
|
|
|
|
cs = cc + GET(cc, 1);
|
|
if (*cs != OP_ALT)
|
|
{
|
|
cc = cs + 1 + LINK_SIZE;
|
|
break;
|
|
}
|
|
goto PROCESS_NON_CAPTURE;
|
|
|
|
case OP_BRA:
|
|
/* There's a special case of OP_BRA, when it is wrapped round a repeated
|
|
OP_RECURSE. We'd like to process the latter at this level so that
|
|
remembering the value works for repeated cases. So we do nothing, but
|
|
set a fudge value to skip over the OP_KET after the recurse. */
|
|
|
|
if (cc[1+LINK_SIZE] == OP_RECURSE && cc[2*(1+LINK_SIZE)] == OP_KET)
|
|
{
|
|
once_fudge = 1 + LINK_SIZE;
|
|
cc += 1 + LINK_SIZE;
|
|
break;
|
|
}
|
|
/* Fall through */
|
|
|
|
case OP_ONCE:
|
|
case OP_SCRIPT_RUN:
|
|
case OP_SBRA:
|
|
case OP_BRAPOS:
|
|
case OP_SBRAPOS:
|
|
PROCESS_NON_CAPTURE:
|
|
d = find_minlength(re, cc, startcode, utf, recurses, countptr,
|
|
backref_cache);
|
|
if (d < 0) return d;
|
|
branchlength += d;
|
|
do cc += GET(cc, 1); while (*cc == OP_ALT);
|
|
cc += 1 + LINK_SIZE;
|
|
break;
|
|
|
|
/* To save time for repeated capturing subpatterns, we remember the
|
|
length of the previous one. Unfortunately we can't do the same for
|
|
the unnumbered ones above. Nor can we do this if (?| is present in the
|
|
pattern because captures with the same number are not then identical. */
|
|
|
|
case OP_CBRA:
|
|
case OP_SCBRA:
|
|
case OP_CBRAPOS:
|
|
case OP_SCBRAPOS:
|
|
recno = (int)GET2(cc, 1+LINK_SIZE);
|
|
if (dupcapused || recno != prev_cap_recno)
|
|
{
|
|
prev_cap_recno = recno;
|
|
prev_cap_d = find_minlength(re, cc, startcode, utf, recurses, countptr,
|
|
backref_cache);
|
|
if (prev_cap_d < 0) return prev_cap_d;
|
|
}
|
|
branchlength += prev_cap_d;
|
|
do cc += GET(cc, 1); while (*cc == OP_ALT);
|
|
cc += 1 + LINK_SIZE;
|
|
break;
|
|
|
|
/* ACCEPT makes things far too complicated; we have to give up. In fact,
|
|
from 10.34 onwards, if a pattern contains (*ACCEPT), this function is not
|
|
used. However, leave the code in place, just in case. */
|
|
|
|
case OP_ACCEPT:
|
|
case OP_ASSERT_ACCEPT:
|
|
return -1;
|
|
|
|
/* Reached end of a branch; if it's a ket it is the end of a nested
|
|
call. If it's ALT it is an alternation in a nested call. If it is END it's
|
|
the end of the outer call. All can be handled by the same code. If the
|
|
length of any branch is zero, there is no need to scan any subsequent
|
|
branches. */
|
|
|
|
case OP_ALT:
|
|
case OP_KET:
|
|
case OP_KETRMAX:
|
|
case OP_KETRMIN:
|
|
case OP_KETRPOS:
|
|
case OP_END:
|
|
if (length < 0 || (!had_recurse && branchlength < length))
|
|
length = branchlength;
|
|
if (op != OP_ALT || length == 0) return length;
|
|
nextbranch = cc + GET(cc, 1);
|
|
cc += 1 + LINK_SIZE;
|
|
branchlength = 0;
|
|
had_recurse = FALSE;
|
|
break;
|
|
|
|
/* Skip over assertive subpatterns */
|
|
|
|
case OP_ASSERT:
|
|
case OP_ASSERT_NOT:
|
|
case OP_ASSERTBACK:
|
|
case OP_ASSERTBACK_NOT:
|
|
case OP_ASSERT_NA:
|
|
case OP_ASSERTBACK_NA:
|
|
do cc += GET(cc, 1); while (*cc == OP_ALT);
|
|
/* Fall through */
|
|
|
|
/* Skip over things that don't match chars */
|
|
|
|
case OP_REVERSE:
|
|
case OP_VREVERSE:
|
|
case OP_CREF:
|
|
case OP_DNCREF:
|
|
case OP_RREF:
|
|
case OP_DNRREF:
|
|
case OP_FALSE:
|
|
case OP_TRUE:
|
|
case OP_CALLOUT:
|
|
case OP_SOD:
|
|
case OP_SOM:
|
|
case OP_EOD:
|
|
case OP_EODN:
|
|
case OP_CIRC:
|
|
case OP_CIRCM:
|
|
case OP_DOLL:
|
|
case OP_DOLLM:
|
|
case OP_NOT_WORD_BOUNDARY:
|
|
case OP_WORD_BOUNDARY:
|
|
case OP_NOT_UCP_WORD_BOUNDARY:
|
|
case OP_UCP_WORD_BOUNDARY:
|
|
cc += PRIV(OP_lengths)[*cc];
|
|
break;
|
|
|
|
case OP_CALLOUT_STR:
|
|
cc += GET(cc, 1 + 2*LINK_SIZE);
|
|
break;
|
|
|
|
/* Skip over a subpattern that has a {0} or {0,x} quantifier */
|
|
|
|
case OP_BRAZERO:
|
|
case OP_BRAMINZERO:
|
|
case OP_BRAPOSZERO:
|
|
case OP_SKIPZERO:
|
|
cc += PRIV(OP_lengths)[*cc];
|
|
do cc += GET(cc, 1); while (*cc == OP_ALT);
|
|
cc += 1 + LINK_SIZE;
|
|
break;
|
|
|
|
/* Handle literal characters and + repetitions */
|
|
|
|
case OP_CHAR:
|
|
case OP_CHARI:
|
|
case OP_NOT:
|
|
case OP_NOTI:
|
|
case OP_PLUS:
|
|
case OP_PLUSI:
|
|
case OP_MINPLUS:
|
|
case OP_MINPLUSI:
|
|
case OP_POSPLUS:
|
|
case OP_POSPLUSI:
|
|
case OP_NOTPLUS:
|
|
case OP_NOTPLUSI:
|
|
case OP_NOTMINPLUS:
|
|
case OP_NOTMINPLUSI:
|
|
case OP_NOTPOSPLUS:
|
|
case OP_NOTPOSPLUSI:
|
|
branchlength++;
|
|
cc += 2;
|
|
#ifdef SUPPORT_UNICODE
|
|
if (utf && HAS_EXTRALEN(cc[-1])) cc += GET_EXTRALEN(cc[-1]);
|
|
#endif
|
|
break;
|
|
|
|
case OP_TYPEPLUS:
|
|
case OP_TYPEMINPLUS:
|
|
case OP_TYPEPOSPLUS:
|
|
branchlength++;
|
|
cc += (cc[1] == OP_PROP || cc[1] == OP_NOTPROP)? 4 : 2;
|
|
break;
|
|
|
|
/* Handle exact repetitions. The count is already in characters, but we
|
|
may need to skip over a multibyte character in UTF mode. */
|
|
|
|
case OP_EXACT:
|
|
case OP_EXACTI:
|
|
case OP_NOTEXACT:
|
|
case OP_NOTEXACTI:
|
|
branchlength += GET2(cc,1);
|
|
cc += 2 + IMM2_SIZE;
|
|
#ifdef SUPPORT_UNICODE
|
|
if (utf && HAS_EXTRALEN(cc[-1])) cc += GET_EXTRALEN(cc[-1]);
|
|
#endif
|
|
break;
|
|
|
|
case OP_TYPEEXACT:
|
|
branchlength += GET2(cc,1);
|
|
cc += 2 + IMM2_SIZE + ((cc[1 + IMM2_SIZE] == OP_PROP
|
|
|| cc[1 + IMM2_SIZE] == OP_NOTPROP)? 2 : 0);
|
|
break;
|
|
|
|
/* Handle single-char non-literal matchers */
|
|
|
|
case OP_PROP:
|
|
case OP_NOTPROP:
|
|
cc += 2;
|
|
/* Fall through */
|
|
|
|
case OP_NOT_DIGIT:
|
|
case OP_DIGIT:
|
|
case OP_NOT_WHITESPACE:
|
|
case OP_WHITESPACE:
|
|
case OP_NOT_WORDCHAR:
|
|
case OP_WORDCHAR:
|
|
case OP_ANY:
|
|
case OP_ALLANY:
|
|
case OP_EXTUNI:
|
|
case OP_HSPACE:
|
|
case OP_NOT_HSPACE:
|
|
case OP_VSPACE:
|
|
case OP_NOT_VSPACE:
|
|
branchlength++;
|
|
cc++;
|
|
break;
|
|
|
|
/* "Any newline" might match two characters, but it also might match just
|
|
one. */
|
|
|
|
case OP_ANYNL:
|
|
branchlength += 1;
|
|
cc++;
|
|
break;
|
|
|
|
/* The single-byte matcher means we can't proceed in UTF mode. (In
|
|
non-UTF mode \C will actually be turned into OP_ALLANY, so won't ever
|
|
appear, but leave the code, just in case.) */
|
|
|
|
case OP_ANYBYTE:
|
|
#ifdef SUPPORT_UNICODE
|
|
if (utf) return -1;
|
|
#endif
|
|
branchlength++;
|
|
cc++;
|
|
break;
|
|
|
|
/* For repeated character types, we have to test for \p and \P, which have
|
|
an extra two bytes of parameters. */
|
|
|
|
case OP_TYPESTAR:
|
|
case OP_TYPEMINSTAR:
|
|
case OP_TYPEQUERY:
|
|
case OP_TYPEMINQUERY:
|
|
case OP_TYPEPOSSTAR:
|
|
case OP_TYPEPOSQUERY:
|
|
if (cc[1] == OP_PROP || cc[1] == OP_NOTPROP) cc += 2;
|
|
cc += PRIV(OP_lengths)[op];
|
|
break;
|
|
|
|
case OP_TYPEUPTO:
|
|
case OP_TYPEMINUPTO:
|
|
case OP_TYPEPOSUPTO:
|
|
if (cc[1 + IMM2_SIZE] == OP_PROP
|
|
|| cc[1 + IMM2_SIZE] == OP_NOTPROP) cc += 2;
|
|
cc += PRIV(OP_lengths)[op];
|
|
break;
|
|
|
|
/* Check a class for variable quantification */
|
|
|
|
case OP_CLASS:
|
|
case OP_NCLASS:
|
|
#ifdef SUPPORT_WIDE_CHARS
|
|
case OP_XCLASS:
|
|
/* The original code caused an unsigned overflow in 64 bit systems,
|
|
so now we use a conditional statement. */
|
|
if (op == OP_XCLASS)
|
|
cc += GET(cc, 1);
|
|
else
|
|
cc += PRIV(OP_lengths)[OP_CLASS];
|
|
#else
|
|
cc += PRIV(OP_lengths)[OP_CLASS];
|
|
#endif
|
|
|
|
switch (*cc)
|
|
{
|
|
case OP_CRPLUS:
|
|
case OP_CRMINPLUS:
|
|
case OP_CRPOSPLUS:
|
|
branchlength++;
|
|
/* Fall through */
|
|
|
|
case OP_CRSTAR:
|
|
case OP_CRMINSTAR:
|
|
case OP_CRQUERY:
|
|
case OP_CRMINQUERY:
|
|
case OP_CRPOSSTAR:
|
|
case OP_CRPOSQUERY:
|
|
cc++;
|
|
break;
|
|
|
|
case OP_CRRANGE:
|
|
case OP_CRMINRANGE:
|
|
case OP_CRPOSRANGE:
|
|
branchlength += GET2(cc,1);
|
|
cc += 1 + 2 * IMM2_SIZE;
|
|
break;
|
|
|
|
default:
|
|
branchlength++;
|
|
break;
|
|
}
|
|
break;
|
|
|
|
/* Backreferences and subroutine calls (OP_RECURSE) are treated in the same
|
|
way: we find the minimum length for the subpattern. A recursion
|
|
(backreference or subroutine) causes an a flag to be set that causes the
|
|
length of this branch to be ignored. The logic is that a recursion can only
|
|
make sense if there is another alternative that stops the recursing. That
|
|
will provide the minimum length (when no recursion happens).
|
|
|
|
If PCRE2_MATCH_UNSET_BACKREF is set, a backreference to an unset bracket
|
|
matches an empty string (by default it causes a matching failure), so in
|
|
that case we must set the minimum length to zero.
|
|
|
|
For backreferenes, if duplicate numbers are present in the pattern we check
|
|
for a reference to a duplicate. If it is, we don't know which version will
|
|
be referenced, so we have to set the minimum length to zero. */
|
|
|
|
/* Duplicate named pattern back reference. */
|
|
|
|
case OP_DNREF:
|
|
case OP_DNREFI:
|
|
if (!dupcapused && (re->overall_options & PCRE2_MATCH_UNSET_BACKREF) == 0)
|
|
{
|
|
int count = GET2(cc, 1+IMM2_SIZE);
|
|
PCRE2_UCHAR *slot =
|
|
(PCRE2_UCHAR *)((uint8_t *)re + sizeof(pcre2_real_code)) +
|
|
GET2(cc, 1) * re->name_entry_size;
|
|
|
|
d = INT_MAX;
|
|
|
|
/* Scan all groups with the same name; find the shortest. */
|
|
|
|
while (count-- > 0)
|
|
{
|
|
int dd, i;
|
|
recno = GET2(slot, 0);
|
|
|
|
if (recno <= backref_cache[0] && backref_cache[recno] >= 0)
|
|
dd = backref_cache[recno];
|
|
else
|
|
{
|
|
ce = cs = (PCRE2_UCHAR *)PRIV(find_bracket)(startcode, utf, recno);
|
|
if (cs == NULL) return -2;
|
|
do ce += GET(ce, 1); while (*ce == OP_ALT);
|
|
|
|
dd = 0;
|
|
if (!dupcapused ||
|
|
(PCRE2_UCHAR *)PRIV(find_bracket)(ce, utf, recno) == NULL)
|
|
{
|
|
if (cc > cs && cc < ce) /* Simple recursion */
|
|
{
|
|
had_recurse = TRUE;
|
|
}
|
|
else
|
|
{
|
|
recurse_check *r = recurses;
|
|
for (r = recurses; r != NULL; r = r->prev)
|
|
if (r->group == cs) break;
|
|
if (r != NULL) /* Mutual recursion */
|
|
{
|
|
had_recurse = TRUE;
|
|
}
|
|
else
|
|
{
|
|
this_recurse.prev = recurses; /* No recursion */
|
|
this_recurse.group = cs;
|
|
dd = find_minlength(re, cs, startcode, utf, &this_recurse,
|
|
countptr, backref_cache);
|
|
if (dd < 0) return dd;
|
|
}
|
|
}
|
|
}
|
|
|
|
backref_cache[recno] = dd;
|
|
for (i = backref_cache[0] + 1; i < recno; i++) backref_cache[i] = -1;
|
|
backref_cache[0] = recno;
|
|
}
|
|
|
|
if (dd < d) d = dd;
|
|
if (d <= 0) break; /* No point looking at any more */
|
|
slot += re->name_entry_size;
|
|
}
|
|
}
|
|
else d = 0;
|
|
cc += 1 + 2*IMM2_SIZE;
|
|
goto REPEAT_BACK_REFERENCE;
|
|
|
|
/* Single back reference by number. References by name are converted to by
|
|
number when there is no duplication. */
|
|
|
|
case OP_REF:
|
|
case OP_REFI:
|
|
recno = GET2(cc, 1);
|
|
if (recno <= backref_cache[0] && backref_cache[recno] >= 0)
|
|
d = backref_cache[recno];
|
|
else
|
|
{
|
|
int i;
|
|
d = 0;
|
|
|
|
if ((re->overall_options & PCRE2_MATCH_UNSET_BACKREF) == 0)
|
|
{
|
|
ce = cs = (PCRE2_UCHAR *)PRIV(find_bracket)(startcode, utf, recno);
|
|
if (cs == NULL) return -2;
|
|
do ce += GET(ce, 1); while (*ce == OP_ALT);
|
|
|
|
if (!dupcapused ||
|
|
(PCRE2_UCHAR *)PRIV(find_bracket)(ce, utf, recno) == NULL)
|
|
{
|
|
if (cc > cs && cc < ce) /* Simple recursion */
|
|
{
|
|
had_recurse = TRUE;
|
|
}
|
|
else
|
|
{
|
|
recurse_check *r = recurses;
|
|
for (r = recurses; r != NULL; r = r->prev) if (r->group == cs) break;
|
|
if (r != NULL) /* Mutual recursion */
|
|
{
|
|
had_recurse = TRUE;
|
|
}
|
|
else /* No recursion */
|
|
{
|
|
this_recurse.prev = recurses;
|
|
this_recurse.group = cs;
|
|
d = find_minlength(re, cs, startcode, utf, &this_recurse, countptr,
|
|
backref_cache);
|
|
if (d < 0) return d;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
backref_cache[recno] = d;
|
|
for (i = backref_cache[0] + 1; i < recno; i++) backref_cache[i] = -1;
|
|
backref_cache[0] = recno;
|
|
}
|
|
|
|
cc += 1 + IMM2_SIZE;
|
|
|
|
/* Handle repeated back references */
|
|
|
|
REPEAT_BACK_REFERENCE:
|
|
switch (*cc)
|
|
{
|
|
case OP_CRSTAR:
|
|
case OP_CRMINSTAR:
|
|
case OP_CRQUERY:
|
|
case OP_CRMINQUERY:
|
|
case OP_CRPOSSTAR:
|
|
case OP_CRPOSQUERY:
|
|
min = 0;
|
|
cc++;
|
|
break;
|
|
|
|
case OP_CRPLUS:
|
|
case OP_CRMINPLUS:
|
|
case OP_CRPOSPLUS:
|
|
min = 1;
|
|
cc++;
|
|
break;
|
|
|
|
case OP_CRRANGE:
|
|
case OP_CRMINRANGE:
|
|
case OP_CRPOSRANGE:
|
|
min = GET2(cc, 1);
|
|
cc += 1 + 2 * IMM2_SIZE;
|
|
break;
|
|
|
|
default:
|
|
min = 1;
|
|
break;
|
|
}
|
|
|
|
/* Take care not to overflow: (1) min and d are ints, so check that their
|
|
product is not greater than INT_MAX. (2) branchlength is limited to
|
|
UINT16_MAX (checked at the top of the loop). */
|
|
|
|
if ((d > 0 && (INT_MAX/d) < min) || UINT16_MAX - branchlength < min*d)
|
|
branchlength = UINT16_MAX;
|
|
else branchlength += min * d;
|
|
break;
|
|
|
|
/* Recursion always refers to the first occurrence of a subpattern with a
|
|
given number. Therefore, we can always make use of caching, even when the
|
|
pattern contains multiple subpatterns with the same number. */
|
|
|
|
case OP_RECURSE:
|
|
cs = ce = (PCRE2_UCHAR *)startcode + GET(cc, 1);
|
|
recno = GET2(cs, 1+LINK_SIZE);
|
|
if (recno == prev_recurse_recno)
|
|
{
|
|
branchlength += prev_recurse_d;
|
|
}
|
|
else
|
|
{
|
|
do ce += GET(ce, 1); while (*ce == OP_ALT);
|
|
if (cc > cs && cc < ce) /* Simple recursion */
|
|
had_recurse = TRUE;
|
|
else
|
|
{
|
|
recurse_check *r = recurses;
|
|
for (r = recurses; r != NULL; r = r->prev) if (r->group == cs) break;
|
|
if (r != NULL) /* Mutual recursion */
|
|
had_recurse = TRUE;
|
|
else
|
|
{
|
|
this_recurse.prev = recurses;
|
|
this_recurse.group = cs;
|
|
prev_recurse_d = find_minlength(re, cs, startcode, utf, &this_recurse,
|
|
countptr, backref_cache);
|
|
if (prev_recurse_d < 0) return prev_recurse_d;
|
|
prev_recurse_recno = recno;
|
|
branchlength += prev_recurse_d;
|
|
}
|
|
}
|
|
}
|
|
cc += 1 + LINK_SIZE + once_fudge;
|
|
once_fudge = 0;
|
|
break;
|
|
|
|
/* Anything else does not or need not match a character. We can get the
|
|
item's length from the table, but for those that can match zero occurrences
|
|
of a character, we must take special action for UTF-8 characters. As it
|
|
happens, the "NOT" versions of these opcodes are used at present only for
|
|
ASCII characters, so they could be omitted from this list. However, in
|
|
future that may change, so we include them here so as not to leave a
|
|
gotcha for a future maintainer. */
|
|
|
|
case OP_UPTO:
|
|
case OP_UPTOI:
|
|
case OP_NOTUPTO:
|
|
case OP_NOTUPTOI:
|
|
case OP_MINUPTO:
|
|
case OP_MINUPTOI:
|
|
case OP_NOTMINUPTO:
|
|
case OP_NOTMINUPTOI:
|
|
case OP_POSUPTO:
|
|
case OP_POSUPTOI:
|
|
case OP_NOTPOSUPTO:
|
|
case OP_NOTPOSUPTOI:
|
|
|
|
case OP_STAR:
|
|
case OP_STARI:
|
|
case OP_NOTSTAR:
|
|
case OP_NOTSTARI:
|
|
case OP_MINSTAR:
|
|
case OP_MINSTARI:
|
|
case OP_NOTMINSTAR:
|
|
case OP_NOTMINSTARI:
|
|
case OP_POSSTAR:
|
|
case OP_POSSTARI:
|
|
case OP_NOTPOSSTAR:
|
|
case OP_NOTPOSSTARI:
|
|
|
|
case OP_QUERY:
|
|
case OP_QUERYI:
|
|
case OP_NOTQUERY:
|
|
case OP_NOTQUERYI:
|
|
case OP_MINQUERY:
|
|
case OP_MINQUERYI:
|
|
case OP_NOTMINQUERY:
|
|
case OP_NOTMINQUERYI:
|
|
case OP_POSQUERY:
|
|
case OP_POSQUERYI:
|
|
case OP_NOTPOSQUERY:
|
|
case OP_NOTPOSQUERYI:
|
|
|
|
cc += PRIV(OP_lengths)[op];
|
|
#ifdef SUPPORT_UNICODE
|
|
if (utf && HAS_EXTRALEN(cc[-1])) cc += GET_EXTRALEN(cc[-1]);
|
|
#endif
|
|
break;
|
|
|
|
/* Skip these, but we need to add in the name length. */
|
|
|
|
case OP_MARK:
|
|
case OP_COMMIT_ARG:
|
|
case OP_PRUNE_ARG:
|
|
case OP_SKIP_ARG:
|
|
case OP_THEN_ARG:
|
|
cc += PRIV(OP_lengths)[op] + cc[1];
|
|
break;
|
|
|
|
/* The remaining opcodes are just skipped over. */
|
|
|
|
case OP_CLOSE:
|
|
case OP_COMMIT:
|
|
case OP_FAIL:
|
|
case OP_PRUNE:
|
|
case OP_SET_SOM:
|
|
case OP_SKIP:
|
|
case OP_THEN:
|
|
cc += PRIV(OP_lengths)[op];
|
|
break;
|
|
|
|
/* This should not occur: we list all opcodes explicitly so that when
|
|
new ones get added they are properly considered. */
|
|
|
|
default:
|
|
return -3;
|
|
}
|
|
}
|
|
/* Control never gets here */
|
|
}
|
|
|
|
|
|
|
|
/*************************************************
|
|
* Set a bit and maybe its alternate case *
|
|
*************************************************/
|
|
|
|
/* Given a character, set its first code unit's bit in the table, and also the
|
|
corresponding bit for the other version of a letter if we are caseless.
|
|
|
|
Arguments:
|
|
re points to the regex block
|
|
p points to the first code unit of the character
|
|
caseless TRUE if caseless
|
|
utf TRUE for UTF mode
|
|
ucp TRUE for UCP mode
|
|
|
|
Returns: pointer after the character
|
|
*/
|
|
|
|
static PCRE2_SPTR
|
|
set_table_bit(pcre2_real_code *re, PCRE2_SPTR p, BOOL caseless, BOOL utf,
|
|
BOOL ucp)
|
|
{
|
|
uint32_t c = *p++; /* First code unit */
|
|
|
|
(void)utf; /* Stop compiler warnings when UTF not supported */
|
|
(void)ucp;
|
|
|
|
/* In 16-bit and 32-bit modes, code units greater than 0xff set the bit for
|
|
0xff. */
|
|
|
|
#if PCRE2_CODE_UNIT_WIDTH != 8
|
|
if (c > 0xff) SET_BIT(0xff); else
|
|
#endif
|
|
|
|
SET_BIT(c);
|
|
|
|
/* In UTF-8 or UTF-16 mode, pick up the remaining code units in order to find
|
|
the end of the character, even when caseless. */
|
|
|
|
#ifdef SUPPORT_UNICODE
|
|
if (utf)
|
|
{
|
|
#if PCRE2_CODE_UNIT_WIDTH == 8
|
|
if (c >= 0xc0) GETUTF8INC(c, p);
|
|
#elif PCRE2_CODE_UNIT_WIDTH == 16
|
|
if ((c & 0xfc00) == 0xd800) GETUTF16INC(c, p);
|
|
#endif
|
|
}
|
|
#endif /* SUPPORT_UNICODE */
|
|
|
|
/* If caseless, handle the other case of the character. */
|
|
|
|
if (caseless)
|
|
{
|
|
#ifdef SUPPORT_UNICODE
|
|
if (utf || ucp)
|
|
{
|
|
c = UCD_OTHERCASE(c);
|
|
#if PCRE2_CODE_UNIT_WIDTH == 8
|
|
if (utf)
|
|
{
|
|
PCRE2_UCHAR buff[6];
|
|
(void)PRIV(ord2utf)(c, buff);
|
|
SET_BIT(buff[0]);
|
|
}
|
|
else if (c < 256) SET_BIT(c);
|
|
#else /* 16-bit or 32-bit mode */
|
|
if (c > 0xff) SET_BIT(0xff); else SET_BIT(c);
|
|
#endif
|
|
}
|
|
|
|
else
|
|
#endif /* SUPPORT_UNICODE */
|
|
|
|
/* Not UTF or UCP */
|
|
|
|
if (MAX_255(c)) SET_BIT(re->tables[fcc_offset + c]);
|
|
}
|
|
|
|
return p;
|
|
}
|
|
|
|
|
|
|
|
/*************************************************
|
|
* Set bits for a positive character type *
|
|
*************************************************/
|
|
|
|
/* This function sets starting bits for a character type. In UTF-8 mode, we can
|
|
only do a direct setting for bytes less than 128, as otherwise there can be
|
|
confusion with bytes in the middle of UTF-8 characters. In a "traditional"
|
|
environment, the tables will only recognize ASCII characters anyway, but in at
|
|
least one Windows environment, some higher bytes bits were set in the tables.
|
|
So we deal with that case by considering the UTF-8 encoding.
|
|
|
|
Arguments:
|
|
re the regex block
|
|
cbit type the type of character wanted
|
|
table_limit 32 for non-UTF-8; 16 for UTF-8
|
|
|
|
Returns: nothing
|
|
*/
|
|
|
|
static void
|
|
set_type_bits(pcre2_real_code *re, int cbit_type, unsigned int table_limit)
|
|
{
|
|
uint32_t c;
|
|
for (c = 0; c < table_limit; c++)
|
|
re->start_bitmap[c] |= re->tables[c+cbits_offset+cbit_type];
|
|
#if defined SUPPORT_UNICODE && PCRE2_CODE_UNIT_WIDTH == 8
|
|
if (table_limit == 32) return;
|
|
for (c = 128; c < 256; c++)
|
|
{
|
|
if ((re->tables[cbits_offset + c/8] & (1u << (c&7))) != 0)
|
|
{
|
|
PCRE2_UCHAR buff[6];
|
|
(void)PRIV(ord2utf)(c, buff);
|
|
SET_BIT(buff[0]);
|
|
}
|
|
}
|
|
#endif /* UTF-8 */
|
|
}
|
|
|
|
|
|
/*************************************************
|
|
* Set bits for a negative character type *
|
|
*************************************************/
|
|
|
|
/* This function sets starting bits for a negative character type such as \D.
|
|
In UTF-8 mode, we can only do a direct setting for bytes less than 128, as
|
|
otherwise there can be confusion with bytes in the middle of UTF-8 characters.
|
|
Unlike in the positive case, where we can set appropriate starting bits for
|
|
specific high-valued UTF-8 characters, in this case we have to set the bits for
|
|
all high-valued characters. The lowest is 0xc2, but we overkill by starting at
|
|
0xc0 (192) for simplicity.
|
|
|
|
Arguments:
|
|
re the regex block
|
|
cbit type the type of character wanted
|
|
table_limit 32 for non-UTF-8; 16 for UTF-8
|
|
|
|
Returns: nothing
|
|
*/
|
|
|
|
static void
|
|
set_nottype_bits(pcre2_real_code *re, int cbit_type, unsigned int table_limit)
|
|
{
|
|
uint32_t c;
|
|
for (c = 0; c < table_limit; c++)
|
|
re->start_bitmap[c] |= (uint8_t)(~(re->tables[c+cbits_offset+cbit_type]));
|
|
#if defined SUPPORT_UNICODE && PCRE2_CODE_UNIT_WIDTH == 8
|
|
if (table_limit != 32) for (c = 24; c < 32; c++) re->start_bitmap[c] = 0xff;
|
|
#endif
|
|
}
|
|
|
|
|
|
|
|
/*************************************************
|
|
* Create bitmap of starting code units *
|
|
*************************************************/
|
|
|
|
/* This function scans a compiled unanchored expression recursively and
|
|
attempts to build a bitmap of the set of possible starting code units whose
|
|
values are less than 256. In 16-bit and 32-bit mode, values above 255 all cause
|
|
the 255 bit to be set. When calling set[_not]_type_bits() in UTF-8 (sic) mode
|
|
we pass a value of 16 rather than 32 as the final argument. (See comments in
|
|
those functions for the reason.)
|
|
|
|
The SSB_CONTINUE return is useful for parenthesized groups in patterns such as
|
|
(a*)b where the group provides some optional starting code units but scanning
|
|
must continue at the outer level to find at least one mandatory code unit. At
|
|
the outermost level, this function fails unless the result is SSB_DONE.
|
|
|
|
We restrict recursion (for nested groups) to 1000 to avoid stack overflow
|
|
issues.
|
|
|
|
Arguments:
|
|
re points to the compiled regex block
|
|
code points to an expression
|
|
utf TRUE if in UTF mode
|
|
ucp TRUE if in UCP mode
|
|
depthptr pointer to recurse depth
|
|
|
|
Returns: SSB_FAIL => Failed to find any starting code units
|
|
SSB_DONE => Found mandatory starting code units
|
|
SSB_CONTINUE => Found optional starting code units
|
|
SSB_UNKNOWN => Hit an unrecognized opcode
|
|
SSB_TOODEEP => Recursion is too deep
|
|
*/
|
|
|
|
static int
|
|
set_start_bits(pcre2_real_code *re, PCRE2_SPTR code, BOOL utf, BOOL ucp,
|
|
int *depthptr)
|
|
{
|
|
uint32_t c;
|
|
int yield = SSB_DONE;
|
|
|
|
#if defined SUPPORT_UNICODE && PCRE2_CODE_UNIT_WIDTH == 8
|
|
int table_limit = utf? 16:32;
|
|
#else
|
|
int table_limit = 32;
|
|
#endif
|
|
|
|
*depthptr += 1;
|
|
if (*depthptr > 1000) return SSB_TOODEEP;
|
|
|
|
do
|
|
{
|
|
BOOL try_next = TRUE;
|
|
PCRE2_SPTR tcode = code + 1 + LINK_SIZE;
|
|
|
|
if (*code == OP_CBRA || *code == OP_SCBRA ||
|
|
*code == OP_CBRAPOS || *code == OP_SCBRAPOS) tcode += IMM2_SIZE;
|
|
|
|
while (try_next) /* Loop for items in this branch */
|
|
{
|
|
int rc;
|
|
PCRE2_SPTR ncode;
|
|
uint8_t *classmap = NULL;
|
|
#ifdef SUPPORT_WIDE_CHARS
|
|
PCRE2_UCHAR xclassflags;
|
|
#endif
|
|
|
|
switch(*tcode)
|
|
{
|
|
/* If we reach something we don't understand, it means a new opcode has
|
|
been created that hasn't been added to this function. Hopefully this
|
|
problem will be discovered during testing. */
|
|
|
|
default:
|
|
return SSB_UNKNOWN;
|
|
|
|
/* Fail for a valid opcode that implies no starting bits. */
|
|
|
|
case OP_ACCEPT:
|
|
case OP_ASSERT_ACCEPT:
|
|
case OP_ALLANY:
|
|
case OP_ANY:
|
|
case OP_ANYBYTE:
|
|
case OP_CIRCM:
|
|
case OP_CLOSE:
|
|
case OP_COMMIT:
|
|
case OP_COMMIT_ARG:
|
|
case OP_COND:
|
|
case OP_CREF:
|
|
case OP_FALSE:
|
|
case OP_TRUE:
|
|
case OP_DNCREF:
|
|
case OP_DNREF:
|
|
case OP_DNREFI:
|
|
case OP_DNRREF:
|
|
case OP_DOLL:
|
|
case OP_DOLLM:
|
|
case OP_END:
|
|
case OP_EOD:
|
|
case OP_EODN:
|
|
case OP_EXTUNI:
|
|
case OP_FAIL:
|
|
case OP_MARK:
|
|
case OP_NOT:
|
|
case OP_NOTEXACT:
|
|
case OP_NOTEXACTI:
|
|
case OP_NOTI:
|
|
case OP_NOTMINPLUS:
|
|
case OP_NOTMINPLUSI:
|
|
case OP_NOTMINQUERY:
|
|
case OP_NOTMINQUERYI:
|
|
case OP_NOTMINSTAR:
|
|
case OP_NOTMINSTARI:
|
|
case OP_NOTMINUPTO:
|
|
case OP_NOTMINUPTOI:
|
|
case OP_NOTPLUS:
|
|
case OP_NOTPLUSI:
|
|
case OP_NOTPOSPLUS:
|
|
case OP_NOTPOSPLUSI:
|
|
case OP_NOTPOSQUERY:
|
|
case OP_NOTPOSQUERYI:
|
|
case OP_NOTPOSSTAR:
|
|
case OP_NOTPOSSTARI:
|
|
case OP_NOTPOSUPTO:
|
|
case OP_NOTPOSUPTOI:
|
|
case OP_NOTPROP:
|
|
case OP_NOTQUERY:
|
|
case OP_NOTQUERYI:
|
|
case OP_NOTSTAR:
|
|
case OP_NOTSTARI:
|
|
case OP_NOTUPTO:
|
|
case OP_NOTUPTOI:
|
|
case OP_NOT_HSPACE:
|
|
case OP_NOT_VSPACE:
|
|
case OP_PRUNE:
|
|
case OP_PRUNE_ARG:
|
|
case OP_RECURSE:
|
|
case OP_REF:
|
|
case OP_REFI:
|
|
case OP_REVERSE:
|
|
case OP_VREVERSE:
|
|
case OP_RREF:
|
|
case OP_SCOND:
|
|
case OP_SET_SOM:
|
|
case OP_SKIP:
|
|
case OP_SKIP_ARG:
|
|
case OP_SOD:
|
|
case OP_SOM:
|
|
case OP_THEN:
|
|
case OP_THEN_ARG:
|
|
return SSB_FAIL;
|
|
|
|
/* OP_CIRC happens only at the start of an anchored branch (multiline ^
|
|
uses OP_CIRCM). Skip over it. */
|
|
|
|
case OP_CIRC:
|
|
tcode += PRIV(OP_lengths)[OP_CIRC];
|
|
break;
|
|
|
|
/* A "real" property test implies no starting bits, but the fake property
|
|
PT_CLIST identifies a list of characters. These lists are short, as they
|
|
are used for characters with more than one "other case", so there is no
|
|
point in recognizing them for OP_NOTPROP. */
|
|
|
|
case OP_PROP:
|
|
if (tcode[1] != PT_CLIST) return SSB_FAIL;
|
|
{
|
|
const uint32_t *p = PRIV(ucd_caseless_sets) + tcode[2];
|
|
while ((c = *p++) < NOTACHAR)
|
|
{
|
|
#if defined SUPPORT_UNICODE && PCRE2_CODE_UNIT_WIDTH == 8
|
|
if (utf)
|
|
{
|
|
PCRE2_UCHAR buff[6];
|
|
(void)PRIV(ord2utf)(c, buff);
|
|
c = buff[0];
|
|
}
|
|
#endif
|
|
if (c > 0xff) SET_BIT(0xff); else SET_BIT(c);
|
|
}
|
|
}
|
|
try_next = FALSE;
|
|
break;
|
|
|
|
/* We can ignore word boundary tests. */
|
|
|
|
case OP_WORD_BOUNDARY:
|
|
case OP_NOT_WORD_BOUNDARY:
|
|
case OP_UCP_WORD_BOUNDARY:
|
|
case OP_NOT_UCP_WORD_BOUNDARY:
|
|
tcode++;
|
|
break;
|
|
|
|
/* For a positive lookahead assertion, inspect what immediately follows,
|
|
ignoring intermediate assertions and callouts. If the next item is one
|
|
that sets a mandatory character, skip this assertion. Otherwise, treat it
|
|
the same as other bracket groups. */
|
|
|
|
case OP_ASSERT:
|
|
case OP_ASSERT_NA:
|
|
ncode = tcode + GET(tcode, 1);
|
|
while (*ncode == OP_ALT) ncode += GET(ncode, 1);
|
|
ncode += 1 + LINK_SIZE;
|
|
|
|
/* Skip irrelevant items */
|
|
|
|
for (BOOL done = FALSE; !done;)
|
|
{
|
|
switch (*ncode)
|
|
{
|
|
case OP_ASSERT:
|
|
case OP_ASSERT_NOT:
|
|
case OP_ASSERTBACK:
|
|
case OP_ASSERTBACK_NOT:
|
|
case OP_ASSERT_NA:
|
|
case OP_ASSERTBACK_NA:
|
|
ncode += GET(ncode, 1);
|
|
while (*ncode == OP_ALT) ncode += GET(ncode, 1);
|
|
ncode += 1 + LINK_SIZE;
|
|
break;
|
|
|
|
case OP_WORD_BOUNDARY:
|
|
case OP_NOT_WORD_BOUNDARY:
|
|
case OP_UCP_WORD_BOUNDARY:
|
|
case OP_NOT_UCP_WORD_BOUNDARY:
|
|
ncode++;
|
|
break;
|
|
|
|
case OP_CALLOUT:
|
|
ncode += PRIV(OP_lengths)[OP_CALLOUT];
|
|
break;
|
|
|
|
case OP_CALLOUT_STR:
|
|
ncode += GET(ncode, 1 + 2*LINK_SIZE);
|
|
break;
|
|
|
|
default:
|
|
done = TRUE;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Now check the next significant item. */
|
|
|
|
switch(*ncode)
|
|
{
|
|
default:
|
|
break;
|
|
|
|
case OP_PROP:
|
|
if (ncode[1] != PT_CLIST) break;
|
|
/* Fall through */
|
|
case OP_ANYNL:
|
|
case OP_CHAR:
|
|
case OP_CHARI:
|
|
case OP_EXACT:
|
|
case OP_EXACTI:
|
|
case OP_HSPACE:
|
|
case OP_MINPLUS:
|
|
case OP_MINPLUSI:
|
|
case OP_PLUS:
|
|
case OP_PLUSI:
|
|
case OP_POSPLUS:
|
|
case OP_POSPLUSI:
|
|
case OP_VSPACE:
|
|
/* Note that these types will only be present in non-UCP mode. */
|
|
case OP_DIGIT:
|
|
case OP_NOT_DIGIT:
|
|
case OP_WORDCHAR:
|
|
case OP_NOT_WORDCHAR:
|
|
case OP_WHITESPACE:
|
|
case OP_NOT_WHITESPACE:
|
|
tcode = ncode;
|
|
continue; /* With the following significant opcode */
|
|
}
|
|
/* Fall through */
|
|
|
|
/* For a group bracket or a positive assertion without an immediately
|
|
following mandatory setting, recurse to set bits from within the
|
|
subpattern. If it can't find anything, we have to give up. If it finds
|
|
some mandatory character(s), we are done for this branch. Otherwise,
|
|
carry on scanning after the subpattern. */
|
|
|
|
case OP_BRA:
|
|
case OP_SBRA:
|
|
case OP_CBRA:
|
|
case OP_SCBRA:
|
|
case OP_BRAPOS:
|
|
case OP_SBRAPOS:
|
|
case OP_CBRAPOS:
|
|
case OP_SCBRAPOS:
|
|
case OP_ONCE:
|
|
case OP_SCRIPT_RUN:
|
|
rc = set_start_bits(re, tcode, utf, ucp, depthptr);
|
|
if (rc == SSB_DONE)
|
|
{
|
|
try_next = FALSE;
|
|
}
|
|
else if (rc == SSB_CONTINUE)
|
|
{
|
|
do tcode += GET(tcode, 1); while (*tcode == OP_ALT);
|
|
tcode += 1 + LINK_SIZE;
|
|
}
|
|
else return rc; /* FAIL, UNKNOWN, or TOODEEP */
|
|
break;
|
|
|
|
/* If we hit ALT or KET, it means we haven't found anything mandatory in
|
|
this branch, though we might have found something optional. For ALT, we
|
|
continue with the next alternative, but we have to arrange that the final
|
|
result from subpattern is SSB_CONTINUE rather than SSB_DONE. For KET,
|
|
return SSB_CONTINUE: if this is the top level, that indicates failure,
|
|
but after a nested subpattern, it causes scanning to continue. */
|
|
|
|
case OP_ALT:
|
|
yield = SSB_CONTINUE;
|
|
try_next = FALSE;
|
|
break;
|
|
|
|
case OP_KET:
|
|
case OP_KETRMAX:
|
|
case OP_KETRMIN:
|
|
case OP_KETRPOS:
|
|
return SSB_CONTINUE;
|
|
|
|
/* Skip over callout */
|
|
|
|
case OP_CALLOUT:
|
|
tcode += PRIV(OP_lengths)[OP_CALLOUT];
|
|
break;
|
|
|
|
case OP_CALLOUT_STR:
|
|
tcode += GET(tcode, 1 + 2*LINK_SIZE);
|
|
break;
|
|
|
|
/* Skip over lookbehind and negative lookahead assertions */
|
|
|
|
case OP_ASSERT_NOT:
|
|
case OP_ASSERTBACK:
|
|
case OP_ASSERTBACK_NOT:
|
|
case OP_ASSERTBACK_NA:
|
|
do tcode += GET(tcode, 1); while (*tcode == OP_ALT);
|
|
tcode += 1 + LINK_SIZE;
|
|
break;
|
|
|
|
/* BRAZERO does the bracket, but carries on. */
|
|
|
|
case OP_BRAZERO:
|
|
case OP_BRAMINZERO:
|
|
case OP_BRAPOSZERO:
|
|
rc = set_start_bits(re, ++tcode, utf, ucp, depthptr);
|
|
if (rc == SSB_FAIL || rc == SSB_UNKNOWN || rc == SSB_TOODEEP) return rc;
|
|
do tcode += GET(tcode,1); while (*tcode == OP_ALT);
|
|
tcode += 1 + LINK_SIZE;
|
|
break;
|
|
|
|
/* SKIPZERO skips the bracket. */
|
|
|
|
case OP_SKIPZERO:
|
|
tcode++;
|
|
do tcode += GET(tcode,1); while (*tcode == OP_ALT);
|
|
tcode += 1 + LINK_SIZE;
|
|
break;
|
|
|
|
/* Single-char * or ? sets the bit and tries the next item */
|
|
|
|
case OP_STAR:
|
|
case OP_MINSTAR:
|
|
case OP_POSSTAR:
|
|
case OP_QUERY:
|
|
case OP_MINQUERY:
|
|
case OP_POSQUERY:
|
|
tcode = set_table_bit(re, tcode + 1, FALSE, utf, ucp);
|
|
break;
|
|
|
|
case OP_STARI:
|
|
case OP_MINSTARI:
|
|
case OP_POSSTARI:
|
|
case OP_QUERYI:
|
|
case OP_MINQUERYI:
|
|
case OP_POSQUERYI:
|
|
tcode = set_table_bit(re, tcode + 1, TRUE, utf, ucp);
|
|
break;
|
|
|
|
/* Single-char upto sets the bit and tries the next */
|
|
|
|
case OP_UPTO:
|
|
case OP_MINUPTO:
|
|
case OP_POSUPTO:
|
|
tcode = set_table_bit(re, tcode + 1 + IMM2_SIZE, FALSE, utf, ucp);
|
|
break;
|
|
|
|
case OP_UPTOI:
|
|
case OP_MINUPTOI:
|
|
case OP_POSUPTOI:
|
|
tcode = set_table_bit(re, tcode + 1 + IMM2_SIZE, TRUE, utf, ucp);
|
|
break;
|
|
|
|
/* At least one single char sets the bit and stops */
|
|
|
|
case OP_EXACT:
|
|
tcode += IMM2_SIZE;
|
|
/* Fall through */
|
|
case OP_CHAR:
|
|
case OP_PLUS:
|
|
case OP_MINPLUS:
|
|
case OP_POSPLUS:
|
|
(void)set_table_bit(re, tcode + 1, FALSE, utf, ucp);
|
|
try_next = FALSE;
|
|
break;
|
|
|
|
case OP_EXACTI:
|
|
tcode += IMM2_SIZE;
|
|
/* Fall through */
|
|
case OP_CHARI:
|
|
case OP_PLUSI:
|
|
case OP_MINPLUSI:
|
|
case OP_POSPLUSI:
|
|
(void)set_table_bit(re, tcode + 1, TRUE, utf, ucp);
|
|
try_next = FALSE;
|
|
break;
|
|
|
|
/* Special spacing and line-terminating items. These recognize specific
|
|
lists of characters. The difference between VSPACE and ANYNL is that the
|
|
latter can match the two-character CRLF sequence, but that is not
|
|
relevant for finding the first character, so their code here is
|
|
identical. */
|
|
|
|
case OP_HSPACE:
|
|
SET_BIT(CHAR_HT);
|
|
SET_BIT(CHAR_SPACE);
|
|
|
|
/* For the 16-bit and 32-bit libraries (which can never be EBCDIC), set
|
|
the bits for 0xA0 and for code units >= 255, independently of UTF. */
|
|
|
|
#if PCRE2_CODE_UNIT_WIDTH != 8
|
|
SET_BIT(0xA0);
|
|
SET_BIT(0xFF);
|
|
#else
|
|
/* For the 8-bit library in UTF-8 mode, set the bits for the first code
|
|
units of horizontal space characters. */
|
|
|
|
#ifdef SUPPORT_UNICODE
|
|
if (utf)
|
|
{
|
|
SET_BIT(0xC2); /* For U+00A0 */
|
|
SET_BIT(0xE1); /* For U+1680, U+180E */
|
|
SET_BIT(0xE2); /* For U+2000 - U+200A, U+202F, U+205F */
|
|
SET_BIT(0xE3); /* For U+3000 */
|
|
}
|
|
else
|
|
#endif
|
|
/* For the 8-bit library not in UTF-8 mode, set the bit for 0xA0, unless
|
|
the code is EBCDIC. */
|
|
{
|
|
#ifndef EBCDIC
|
|
SET_BIT(0xA0);
|
|
#endif /* Not EBCDIC */
|
|
}
|
|
#endif /* 8-bit support */
|
|
|
|
try_next = FALSE;
|
|
break;
|
|
|
|
case OP_ANYNL:
|
|
case OP_VSPACE:
|
|
SET_BIT(CHAR_LF);
|
|
SET_BIT(CHAR_VT);
|
|
SET_BIT(CHAR_FF);
|
|
SET_BIT(CHAR_CR);
|
|
|
|
/* For the 16-bit and 32-bit libraries (which can never be EBCDIC), set
|
|
the bits for NEL and for code units >= 255, independently of UTF. */
|
|
|
|
#if PCRE2_CODE_UNIT_WIDTH != 8
|
|
SET_BIT(CHAR_NEL);
|
|
SET_BIT(0xFF);
|
|
#else
|
|
/* For the 8-bit library in UTF-8 mode, set the bits for the first code
|
|
units of vertical space characters. */
|
|
|
|
#ifdef SUPPORT_UNICODE
|
|
if (utf)
|
|
{
|
|
SET_BIT(0xC2); /* For U+0085 (NEL) */
|
|
SET_BIT(0xE2); /* For U+2028, U+2029 */
|
|
}
|
|
else
|
|
#endif
|
|
/* For the 8-bit library not in UTF-8 mode, set the bit for NEL. */
|
|
{
|
|
SET_BIT(CHAR_NEL);
|
|
}
|
|
#endif /* 8-bit support */
|
|
|
|
try_next = FALSE;
|
|
break;
|
|
|
|
/* Single character types set the bits and stop. Note that if PCRE2_UCP
|
|
is set, we do not see these opcodes because \d etc are converted to
|
|
properties. Therefore, these apply in the case when only characters less
|
|
than 256 are recognized to match the types. */
|
|
|
|
case OP_NOT_DIGIT:
|
|
set_nottype_bits(re, cbit_digit, table_limit);
|
|
try_next = FALSE;
|
|
break;
|
|
|
|
case OP_DIGIT:
|
|
set_type_bits(re, cbit_digit, table_limit);
|
|
try_next = FALSE;
|
|
break;
|
|
|
|
case OP_NOT_WHITESPACE:
|
|
set_nottype_bits(re, cbit_space, table_limit);
|
|
try_next = FALSE;
|
|
break;
|
|
|
|
case OP_WHITESPACE:
|
|
set_type_bits(re, cbit_space, table_limit);
|
|
try_next = FALSE;
|
|
break;
|
|
|
|
case OP_NOT_WORDCHAR:
|
|
set_nottype_bits(re, cbit_word, table_limit);
|
|
try_next = FALSE;
|
|
break;
|
|
|
|
case OP_WORDCHAR:
|
|
set_type_bits(re, cbit_word, table_limit);
|
|
try_next = FALSE;
|
|
break;
|
|
|
|
/* One or more character type fudges the pointer and restarts, knowing
|
|
it will hit a single character type and stop there. */
|
|
|
|
case OP_TYPEPLUS:
|
|
case OP_TYPEMINPLUS:
|
|
case OP_TYPEPOSPLUS:
|
|
tcode++;
|
|
break;
|
|
|
|
case OP_TYPEEXACT:
|
|
tcode += 1 + IMM2_SIZE;
|
|
break;
|
|
|
|
/* Zero or more repeats of character types set the bits and then
|
|
try again. */
|
|
|
|
case OP_TYPEUPTO:
|
|
case OP_TYPEMINUPTO:
|
|
case OP_TYPEPOSUPTO:
|
|
tcode += IMM2_SIZE; /* Fall through */
|
|
|
|
case OP_TYPESTAR:
|
|
case OP_TYPEMINSTAR:
|
|
case OP_TYPEPOSSTAR:
|
|
case OP_TYPEQUERY:
|
|
case OP_TYPEMINQUERY:
|
|
case OP_TYPEPOSQUERY:
|
|
switch(tcode[1])
|
|
{
|
|
default:
|
|
case OP_ANY:
|
|
case OP_ALLANY:
|
|
return SSB_FAIL;
|
|
|
|
case OP_HSPACE:
|
|
SET_BIT(CHAR_HT);
|
|
SET_BIT(CHAR_SPACE);
|
|
|
|
/* For the 16-bit and 32-bit libraries (which can never be EBCDIC), set
|
|
the bits for 0xA0 and for code units >= 255, independently of UTF. */
|
|
|
|
#if PCRE2_CODE_UNIT_WIDTH != 8
|
|
SET_BIT(0xA0);
|
|
SET_BIT(0xFF);
|
|
#else
|
|
/* For the 8-bit library in UTF-8 mode, set the bits for the first code
|
|
units of horizontal space characters. */
|
|
|
|
#ifdef SUPPORT_UNICODE
|
|
if (utf)
|
|
{
|
|
SET_BIT(0xC2); /* For U+00A0 */
|
|
SET_BIT(0xE1); /* For U+1680, U+180E */
|
|
SET_BIT(0xE2); /* For U+2000 - U+200A, U+202F, U+205F */
|
|
SET_BIT(0xE3); /* For U+3000 */
|
|
}
|
|
else
|
|
#endif
|
|
/* For the 8-bit library not in UTF-8 mode, set the bit for 0xA0, unless
|
|
the code is EBCDIC. */
|
|
{
|
|
#ifndef EBCDIC
|
|
SET_BIT(0xA0);
|
|
#endif /* Not EBCDIC */
|
|
}
|
|
#endif /* 8-bit support */
|
|
break;
|
|
|
|
case OP_ANYNL:
|
|
case OP_VSPACE:
|
|
SET_BIT(CHAR_LF);
|
|
SET_BIT(CHAR_VT);
|
|
SET_BIT(CHAR_FF);
|
|
SET_BIT(CHAR_CR);
|
|
|
|
/* For the 16-bit and 32-bit libraries (which can never be EBCDIC), set
|
|
the bits for NEL and for code units >= 255, independently of UTF. */
|
|
|
|
#if PCRE2_CODE_UNIT_WIDTH != 8
|
|
SET_BIT(CHAR_NEL);
|
|
SET_BIT(0xFF);
|
|
#else
|
|
/* For the 8-bit library in UTF-8 mode, set the bits for the first code
|
|
units of vertical space characters. */
|
|
|
|
#ifdef SUPPORT_UNICODE
|
|
if (utf)
|
|
{
|
|
SET_BIT(0xC2); /* For U+0085 (NEL) */
|
|
SET_BIT(0xE2); /* For U+2028, U+2029 */
|
|
}
|
|
else
|
|
#endif
|
|
/* For the 8-bit library not in UTF-8 mode, set the bit for NEL. */
|
|
{
|
|
SET_BIT(CHAR_NEL);
|
|
}
|
|
#endif /* 8-bit support */
|
|
break;
|
|
|
|
case OP_NOT_DIGIT:
|
|
set_nottype_bits(re, cbit_digit, table_limit);
|
|
break;
|
|
|
|
case OP_DIGIT:
|
|
set_type_bits(re, cbit_digit, table_limit);
|
|
break;
|
|
|
|
case OP_NOT_WHITESPACE:
|
|
set_nottype_bits(re, cbit_space, table_limit);
|
|
break;
|
|
|
|
case OP_WHITESPACE:
|
|
set_type_bits(re, cbit_space, table_limit);
|
|
break;
|
|
|
|
case OP_NOT_WORDCHAR:
|
|
set_nottype_bits(re, cbit_word, table_limit);
|
|
break;
|
|
|
|
case OP_WORDCHAR:
|
|
set_type_bits(re, cbit_word, table_limit);
|
|
break;
|
|
}
|
|
|
|
tcode += 2;
|
|
break;
|
|
|
|
/* Extended class: if there are any property checks, or if this is a
|
|
negative XCLASS without a map, give up. If there are no property checks,
|
|
there must be wide characters on the XCLASS list, because otherwise an
|
|
XCLASS would not have been created. This means that code points >= 255
|
|
are potential starters. In the UTF-8 case we can scan them and set bits
|
|
for the relevant leading bytes. */
|
|
|
|
#ifdef SUPPORT_WIDE_CHARS
|
|
case OP_XCLASS:
|
|
xclassflags = tcode[1 + LINK_SIZE];
|
|
if ((xclassflags & XCL_HASPROP) != 0 ||
|
|
(xclassflags & (XCL_MAP|XCL_NOT)) == XCL_NOT)
|
|
return SSB_FAIL;
|
|
|
|
/* We have a positive XCLASS or a negative one without a map. Set up the
|
|
map pointer if there is one, and fall through. */
|
|
|
|
classmap = ((xclassflags & XCL_MAP) == 0)? NULL :
|
|
(uint8_t *)(tcode + 1 + LINK_SIZE + 1);
|
|
|
|
/* In UTF-8 mode, scan the character list and set bits for leading bytes,
|
|
then jump to handle the map. */
|
|
|
|
#if PCRE2_CODE_UNIT_WIDTH == 8
|
|
if (utf && (xclassflags & XCL_NOT) == 0)
|
|
{
|
|
PCRE2_UCHAR b, e;
|
|
PCRE2_SPTR p = tcode + 1 + LINK_SIZE + 1 + ((classmap == NULL)? 0:32);
|
|
tcode += GET(tcode, 1);
|
|
|
|
for (;;) switch (*p++)
|
|
{
|
|
case XCL_SINGLE:
|
|
b = *p++;
|
|
while ((*p & 0xc0) == 0x80) p++;
|
|
re->start_bitmap[b/8] |= (1u << (b&7));
|
|
break;
|
|
|
|
case XCL_RANGE:
|
|
b = *p++;
|
|
while ((*p & 0xc0) == 0x80) p++;
|
|
e = *p++;
|
|
while ((*p & 0xc0) == 0x80) p++;
|
|
for (; b <= e; b++)
|
|
re->start_bitmap[b/8] |= (1u << (b&7));
|
|
break;
|
|
|
|
case XCL_END:
|
|
goto HANDLE_CLASSMAP;
|
|
|
|
default:
|
|
return SSB_UNKNOWN; /* Internal error, should not occur */
|
|
}
|
|
}
|
|
#endif /* SUPPORT_UNICODE && PCRE2_CODE_UNIT_WIDTH == 8 */
|
|
#endif /* SUPPORT_WIDE_CHARS */
|
|
|
|
/* It seems that the fall through comment must be outside the #ifdef if
|
|
it is to avoid the gcc compiler warning. */
|
|
|
|
/* Fall through */
|
|
|
|
/* Enter here for a negative non-XCLASS. In the 8-bit library, if we are
|
|
in UTF mode, any byte with a value >= 0xc4 is a potentially valid starter
|
|
because it starts a character with a value > 255. In 8-bit non-UTF mode,
|
|
there is no difference between CLASS and NCLASS. In all other wide
|
|
character modes, set the 0xFF bit to indicate code units >= 255. */
|
|
|
|
case OP_NCLASS:
|
|
#if defined SUPPORT_UNICODE && PCRE2_CODE_UNIT_WIDTH == 8
|
|
if (utf)
|
|
{
|
|
re->start_bitmap[24] |= 0xf0; /* Bits for 0xc4 - 0xc8 */
|
|
memset(re->start_bitmap+25, 0xff, 7); /* Bits for 0xc9 - 0xff */
|
|
}
|
|
#elif PCRE2_CODE_UNIT_WIDTH != 8
|
|
SET_BIT(0xFF); /* For characters >= 255 */
|
|
#endif
|
|
/* Fall through */
|
|
|
|
/* Enter here for a positive non-XCLASS. If we have fallen through from
|
|
an XCLASS, classmap will already be set; just advance the code pointer.
|
|
Otherwise, set up classmap for a a non-XCLASS and advance past it. */
|
|
|
|
case OP_CLASS:
|
|
if (*tcode == OP_XCLASS) tcode += GET(tcode, 1); else
|
|
{
|
|
classmap = (uint8_t *)(++tcode);
|
|
tcode += 32 / sizeof(PCRE2_UCHAR);
|
|
}
|
|
|
|
/* When wide characters are supported, classmap may be NULL. In UTF-8
|
|
(sic) mode, the bits in a class bit map correspond to character values,
|
|
not to byte values. However, the bit map we are constructing is for byte
|
|
values. So we have to do a conversion for characters whose code point is
|
|
greater than 127. In fact, there are only two possible starting bytes for
|
|
characters in the range 128 - 255. */
|
|
|
|
#if defined SUPPORT_WIDE_CHARS && PCRE2_CODE_UNIT_WIDTH == 8
|
|
HANDLE_CLASSMAP:
|
|
#endif
|
|
if (classmap != NULL)
|
|
{
|
|
#if defined SUPPORT_UNICODE && PCRE2_CODE_UNIT_WIDTH == 8
|
|
if (utf)
|
|
{
|
|
for (c = 0; c < 16; c++) re->start_bitmap[c] |= classmap[c];
|
|
for (c = 128; c < 256; c++)
|
|
{
|
|
if ((classmap[c/8] & (1u << (c&7))) != 0)
|
|
{
|
|
int d = (c >> 6) | 0xc0; /* Set bit for this starter */
|
|
re->start_bitmap[d/8] |= (1u << (d&7)); /* and then skip on to the */
|
|
c = (c & 0xc0) + 0x40 - 1; /* next relevant character. */
|
|
}
|
|
}
|
|
}
|
|
else
|
|
#endif
|
|
/* In all modes except UTF-8, the two bit maps are compatible. */
|
|
|
|
{
|
|
for (c = 0; c < 32; c++) re->start_bitmap[c] |= classmap[c];
|
|
}
|
|
}
|
|
|
|
/* Act on what follows the class. For a zero minimum repeat, continue;
|
|
otherwise stop processing. */
|
|
|
|
switch (*tcode)
|
|
{
|
|
case OP_CRSTAR:
|
|
case OP_CRMINSTAR:
|
|
case OP_CRQUERY:
|
|
case OP_CRMINQUERY:
|
|
case OP_CRPOSSTAR:
|
|
case OP_CRPOSQUERY:
|
|
tcode++;
|
|
break;
|
|
|
|
case OP_CRRANGE:
|
|
case OP_CRMINRANGE:
|
|
case OP_CRPOSRANGE:
|
|
if (GET2(tcode, 1) == 0) tcode += 1 + 2 * IMM2_SIZE;
|
|
else try_next = FALSE;
|
|
break;
|
|
|
|
default:
|
|
try_next = FALSE;
|
|
break;
|
|
}
|
|
break; /* End of class handling case */
|
|
} /* End of switch for opcodes */
|
|
} /* End of try_next loop */
|
|
|
|
code += GET(code, 1); /* Advance to next branch */
|
|
}
|
|
while (*code == OP_ALT);
|
|
|
|
return yield;
|
|
}
|
|
|
|
|
|
|
|
/*************************************************
|
|
* Study a compiled expression *
|
|
*************************************************/
|
|
|
|
/* This function is handed a compiled expression that it must study to produce
|
|
information that will speed up the matching.
|
|
|
|
Argument:
|
|
re points to the compiled expression
|
|
|
|
Returns: 0 normally; non-zero should never normally occur
|
|
1 unknown opcode in set_start_bits
|
|
2 missing capturing bracket
|
|
3 unknown opcode in find_minlength
|
|
*/
|
|
|
|
int
|
|
PRIV(study)(pcre2_real_code *re)
|
|
{
|
|
int count = 0;
|
|
PCRE2_UCHAR *code;
|
|
BOOL utf = (re->overall_options & PCRE2_UTF) != 0;
|
|
BOOL ucp = (re->overall_options & PCRE2_UCP) != 0;
|
|
|
|
/* Find start of compiled code */
|
|
|
|
code = (PCRE2_UCHAR *)((uint8_t *)re + sizeof(pcre2_real_code)) +
|
|
re->name_entry_size * re->name_count;
|
|
|
|
/* For a pattern that has a first code unit, or a multiline pattern that
|
|
matches only at "line start", there is no point in seeking a list of starting
|
|
code units. */
|
|
|
|
if ((re->flags & (PCRE2_FIRSTSET|PCRE2_STARTLINE)) == 0)
|
|
{
|
|
int depth = 0;
|
|
int rc = set_start_bits(re, code, utf, ucp, &depth);
|
|
if (rc == SSB_UNKNOWN) return 1;
|
|
|
|
/* If a list of starting code units was set up, scan the list to see if only
|
|
one or two were listed. Having only one listed is rare because usually a
|
|
single starting code unit will have been recognized and PCRE2_FIRSTSET set.
|
|
If two are listed, see if they are caseless versions of the same character;
|
|
if so we can replace the list with a caseless first code unit. This gives
|
|
better performance and is plausibly worth doing for patterns such as [Ww]ord
|
|
or (word|WORD). */
|
|
|
|
if (rc == SSB_DONE)
|
|
{
|
|
int i;
|
|
int a = -1;
|
|
int b = -1;
|
|
uint8_t *p = re->start_bitmap;
|
|
uint32_t flags = PCRE2_FIRSTMAPSET;
|
|
|
|
for (i = 0; i < 256; p++, i += 8)
|
|
{
|
|
uint8_t x = *p;
|
|
if (x != 0)
|
|
{
|
|
int c;
|
|
uint8_t y = x & (~x + 1); /* Least significant bit */
|
|
if (y != x) goto DONE; /* More than one bit set */
|
|
|
|
/* In the 16-bit and 32-bit libraries, the bit for 0xff means "0xff and
|
|
all wide characters", so we cannot use it here. */
|
|
|
|
#if PCRE2_CODE_UNIT_WIDTH != 8
|
|
if (i == 248 && x == 0x80) goto DONE;
|
|
#endif
|
|
|
|
/* Compute the character value */
|
|
|
|
c = i;
|
|
switch (x)
|
|
{
|
|
case 1: break;
|
|
case 2: c += 1; break; case 4: c += 2; break;
|
|
case 8: c += 3; break; case 16: c += 4; break;
|
|
case 32: c += 5; break; case 64: c += 6; break;
|
|
case 128: c += 7; break;
|
|
}
|
|
|
|
/* c contains the code unit value, in the range 0-255. In 8-bit UTF
|
|
mode, only values < 128 can be used. In all the other cases, c is a
|
|
character value. */
|
|
|
|
#if PCRE2_CODE_UNIT_WIDTH == 8
|
|
if (utf && c > 127) goto DONE;
|
|
#endif
|
|
if (a < 0) a = c; /* First one found, save in a */
|
|
else if (b < 0) /* Second one found */
|
|
{
|
|
int d = TABLE_GET((unsigned int)c, re->tables + fcc_offset, c);
|
|
|
|
#ifdef SUPPORT_UNICODE
|
|
if (utf || ucp)
|
|
{
|
|
if (UCD_CASESET(c) != 0) goto DONE; /* Multiple case set */
|
|
if (c > 127) d = UCD_OTHERCASE(c);
|
|
}
|
|
#endif /* SUPPORT_UNICODE */
|
|
|
|
if (d != a) goto DONE; /* Not the other case of a */
|
|
b = c; /* Save second in b */
|
|
}
|
|
else goto DONE; /* More than two characters found */
|
|
}
|
|
}
|
|
|
|
/* Replace the start code unit bits with a first code unit, but only if it
|
|
is not the same as a required later code unit. This is because a search for
|
|
a required code unit starts after an explicit first code unit, but at a
|
|
code unit found from the bitmap. Patterns such as /a*a/ don't work
|
|
if both the start unit and required unit are the same. */
|
|
|
|
if (a >= 0 &&
|
|
(
|
|
(re->flags & PCRE2_LASTSET) == 0 ||
|
|
(
|
|
re->last_codeunit != (uint32_t)a &&
|
|
(b < 0 || re->last_codeunit != (uint32_t)b)
|
|
)
|
|
))
|
|
{
|
|
re->first_codeunit = a;
|
|
flags = PCRE2_FIRSTSET;
|
|
if (b >= 0) flags |= PCRE2_FIRSTCASELESS;
|
|
}
|
|
|
|
DONE:
|
|
re->flags |= flags;
|
|
}
|
|
}
|
|
|
|
/* Find the minimum length of subject string. If the pattern can match an empty
|
|
string, the minimum length is already known. If the pattern contains (*ACCEPT)
|
|
all bets are off, and we don't even try to find a minimum length. If there are
|
|
more back references than the size of the vector we are going to cache them in,
|
|
do nothing. A pattern that complicated will probably take a long time to
|
|
analyze and may in any case turn out to be too complicated. Note that back
|
|
reference minima are held as 16-bit numbers. */
|
|
|
|
if ((re->flags & (PCRE2_MATCH_EMPTY|PCRE2_HASACCEPT)) == 0 &&
|
|
re->top_backref <= MAX_CACHE_BACKREF)
|
|
{
|
|
int min;
|
|
int backref_cache[MAX_CACHE_BACKREF+1];
|
|
backref_cache[0] = 0; /* Highest one that is set */
|
|
min = find_minlength(re, code, code, utf, NULL, &count, backref_cache);
|
|
switch(min)
|
|
{
|
|
case -1: /* \C in UTF mode or over-complex regex */
|
|
break; /* Leave minlength unchanged (will be zero) */
|
|
|
|
case -2:
|
|
return 2; /* missing capturing bracket */
|
|
|
|
case -3:
|
|
return 3; /* unrecognized opcode */
|
|
|
|
default:
|
|
re->minlength = (min > UINT16_MAX)? UINT16_MAX : min;
|
|
break;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* End of pcre2_study.c */
|