mirror of
https://github.com/chibicitiberiu/rainmeter-studio.git
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1127 lines
31 KiB
C
1127 lines
31 KiB
C
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/*************************************************
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* Perl-Compatible Regular Expressions *
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*************************************************/
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/* PCRE is a library of functions to support regular expressions whose syntax
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and semantics are as close as possible to those of the Perl 5 language.
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Written by Philip Hazel
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Copyright (c) 1997-2010 University of Cambridge
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-----------------------------------------------------------------------------
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are met:
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* Redistributions of source code must retain the above copyright notice,
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this list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above copyright
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notice, this list of conditions and the following disclaimer in the
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documentation and/or other materials provided with the distribution.
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* Neither the name of the University of Cambridge nor the names of its
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contributors may be used to endorse or promote products derived from
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this software without specific prior written permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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POSSIBILITY OF SUCH DAMAGE.
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-----------------------------------------------------------------------------
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*/
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/* This module contains the external function pcre_study(), along with local
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supporting functions. */
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#ifdef HAVE_CONFIG_H
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#include "config.h"
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#endif
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#include "pcre_internal.h"
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#define SET_BIT(c) start_bits[c/8] |= (1 << (c&7))
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/* Returns from set_start_bits() */
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enum { SSB_FAIL, SSB_DONE, SSB_CONTINUE };
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/*************************************************
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* Find the minimum subject length for a group *
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*************************************************/
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/* Scan a parenthesized group and compute the minimum length of subject that
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is needed to match it. This is a lower bound; it does not mean there is a
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string of that length that matches. In UTF8 mode, the result is in characters
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rather than bytes.
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Arguments:
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code pointer to start of group (the bracket)
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startcode pointer to start of the whole pattern
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options the compiling options
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Returns: the minimum length
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-1 if \C was encountered
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-2 internal error (missing capturing bracket)
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*/
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static int
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find_minlength(const uschar *code, const uschar *startcode, int options)
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{
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int length = -1;
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BOOL utf8 = (options & PCRE_UTF8) != 0;
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BOOL had_recurse = FALSE;
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register int branchlength = 0;
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register uschar *cc = (uschar *)code + 1 + LINK_SIZE;
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if (*code == OP_CBRA || *code == OP_SCBRA) cc += 2;
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/* Scan along the opcodes for this branch. If we get to the end of the
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branch, check the length against that of the other branches. */
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for (;;)
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{
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int d, min;
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uschar *cs, *ce;
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register int op = *cc;
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switch (op)
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{
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case OP_COND:
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case OP_SCOND:
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/* If there is only one branch in a condition, the implied branch has zero
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length, so we don't add anything. This covers the DEFINE "condition"
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automatically. */
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cs = cc + GET(cc, 1);
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if (*cs != OP_ALT)
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{
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cc = cs + 1 + LINK_SIZE;
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break;
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}
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/* Otherwise we can fall through and treat it the same as any other
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subpattern. */
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case OP_CBRA:
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case OP_SCBRA:
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case OP_BRA:
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case OP_SBRA:
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case OP_ONCE:
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d = find_minlength(cc, startcode, options);
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if (d < 0) return d;
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branchlength += d;
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do cc += GET(cc, 1); while (*cc == OP_ALT);
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cc += 1 + LINK_SIZE;
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break;
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/* Reached end of a branch; if it's a ket it is the end of a nested
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call. If it's ALT it is an alternation in a nested call. If it is
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END it's the end of the outer call. All can be handled by the same code. */
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case OP_ALT:
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case OP_KET:
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case OP_KETRMAX:
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case OP_KETRMIN:
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case OP_END:
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if (length < 0 || (!had_recurse && branchlength < length))
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length = branchlength;
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if (*cc != OP_ALT) return length;
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cc += 1 + LINK_SIZE;
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branchlength = 0;
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had_recurse = FALSE;
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break;
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/* Skip over assertive subpatterns */
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case OP_ASSERT:
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case OP_ASSERT_NOT:
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case OP_ASSERTBACK:
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case OP_ASSERTBACK_NOT:
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do cc += GET(cc, 1); while (*cc == OP_ALT);
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/* Fall through */
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/* Skip over things that don't match chars */
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case OP_REVERSE:
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case OP_CREF:
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case OP_NCREF:
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case OP_RREF:
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case OP_NRREF:
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case OP_DEF:
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case OP_OPT:
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case OP_CALLOUT:
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case OP_SOD:
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case OP_SOM:
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case OP_EOD:
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case OP_EODN:
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case OP_CIRC:
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case OP_DOLL:
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case OP_NOT_WORD_BOUNDARY:
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case OP_WORD_BOUNDARY:
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cc += _pcre_OP_lengths[*cc];
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break;
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/* Skip over a subpattern that has a {0} or {0,x} quantifier */
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case OP_BRAZERO:
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case OP_BRAMINZERO:
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case OP_SKIPZERO:
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cc += _pcre_OP_lengths[*cc];
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do cc += GET(cc, 1); while (*cc == OP_ALT);
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cc += 1 + LINK_SIZE;
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break;
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/* Handle literal characters and + repetitions */
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case OP_CHAR:
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case OP_CHARNC:
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case OP_NOT:
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case OP_PLUS:
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case OP_MINPLUS:
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case OP_POSPLUS:
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case OP_NOTPLUS:
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case OP_NOTMINPLUS:
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case OP_NOTPOSPLUS:
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branchlength++;
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cc += 2;
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#ifdef SUPPORT_UTF8
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if (utf8 && cc[-1] >= 0xc0) cc += _pcre_utf8_table4[cc[-1] & 0x3f];
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#endif
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break;
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case OP_TYPEPLUS:
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case OP_TYPEMINPLUS:
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case OP_TYPEPOSPLUS:
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branchlength++;
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cc += (cc[1] == OP_PROP || cc[1] == OP_NOTPROP)? 4 : 2;
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break;
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/* Handle exact repetitions. The count is already in characters, but we
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need to skip over a multibyte character in UTF8 mode. */
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case OP_EXACT:
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case OP_NOTEXACT:
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branchlength += GET2(cc,1);
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cc += 4;
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#ifdef SUPPORT_UTF8
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if (utf8 && cc[-1] >= 0xc0) cc += _pcre_utf8_table4[cc[-1] & 0x3f];
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#endif
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break;
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case OP_TYPEEXACT:
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branchlength += GET2(cc,1);
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cc += (cc[3] == OP_PROP || cc[3] == OP_NOTPROP)? 6 : 4;
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break;
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/* Handle single-char non-literal matchers */
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case OP_PROP:
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case OP_NOTPROP:
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cc += 2;
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/* Fall through */
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case OP_NOT_DIGIT:
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case OP_DIGIT:
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case OP_NOT_WHITESPACE:
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case OP_WHITESPACE:
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case OP_NOT_WORDCHAR:
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case OP_WORDCHAR:
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case OP_ANY:
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case OP_ALLANY:
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case OP_EXTUNI:
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case OP_HSPACE:
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case OP_NOT_HSPACE:
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case OP_VSPACE:
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case OP_NOT_VSPACE:
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branchlength++;
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cc++;
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break;
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/* "Any newline" might match two characters */
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case OP_ANYNL:
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branchlength += 2;
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cc++;
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break;
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/* The single-byte matcher means we can't proceed in UTF-8 mode */
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case OP_ANYBYTE:
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#ifdef SUPPORT_UTF8
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if (utf8) return -1;
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#endif
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branchlength++;
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cc++;
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break;
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/* For repeated character types, we have to test for \p and \P, which have
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an extra two bytes of parameters. */
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case OP_TYPESTAR:
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case OP_TYPEMINSTAR:
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case OP_TYPEQUERY:
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case OP_TYPEMINQUERY:
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case OP_TYPEPOSSTAR:
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case OP_TYPEPOSQUERY:
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if (cc[1] == OP_PROP || cc[1] == OP_NOTPROP) cc += 2;
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cc += _pcre_OP_lengths[op];
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break;
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case OP_TYPEUPTO:
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case OP_TYPEMINUPTO:
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case OP_TYPEPOSUPTO:
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if (cc[3] == OP_PROP || cc[3] == OP_NOTPROP) cc += 2;
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cc += _pcre_OP_lengths[op];
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break;
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/* Check a class for variable quantification */
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#ifdef SUPPORT_UTF8
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case OP_XCLASS:
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cc += GET(cc, 1) - 33;
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/* Fall through */
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#endif
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case OP_CLASS:
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case OP_NCLASS:
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cc += 33;
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switch (*cc)
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{
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case OP_CRPLUS:
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case OP_CRMINPLUS:
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branchlength++;
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/* Fall through */
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case OP_CRSTAR:
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case OP_CRMINSTAR:
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case OP_CRQUERY:
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case OP_CRMINQUERY:
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cc++;
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break;
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case OP_CRRANGE:
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case OP_CRMINRANGE:
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branchlength += GET2(cc,1);
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cc += 5;
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break;
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default:
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||
|
branchlength++;
|
||
|
break;
|
||
|
}
|
||
|
break;
|
||
|
|
||
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/* Backreferences and subroutine calls are treated in the same way: we find
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the minimum length for the subpattern. A recursion, however, 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
|
||
|
alternation that stops the recursing. That will provide the minimum length
|
||
|
(when no recursion happens). A backreference within the group that it is
|
||
|
referencing behaves in the same way.
|
||
|
|
||
|
If PCRE_JAVASCRIPT_COMPAT 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. */
|
||
|
|
||
|
case OP_REF:
|
||
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if ((options & PCRE_JAVASCRIPT_COMPAT) == 0)
|
||
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{
|
||
|
ce = cs = (uschar *)_pcre_find_bracket(startcode, utf8, GET2(cc, 1));
|
||
|
if (cs == NULL) return -2;
|
||
|
do ce += GET(ce, 1); while (*ce == OP_ALT);
|
||
|
if (cc > cs && cc < ce)
|
||
|
{
|
||
|
d = 0;
|
||
|
had_recurse = TRUE;
|
||
|
}
|
||
|
else d = find_minlength(cs, startcode, options);
|
||
|
}
|
||
|
else d = 0;
|
||
|
cc += 3;
|
||
|
|
||
|
/* Handle repeated back references */
|
||
|
|
||
|
switch (*cc)
|
||
|
{
|
||
|
case OP_CRSTAR:
|
||
|
case OP_CRMINSTAR:
|
||
|
case OP_CRQUERY:
|
||
|
case OP_CRMINQUERY:
|
||
|
min = 0;
|
||
|
cc++;
|
||
|
break;
|
||
|
|
||
|
case OP_CRRANGE:
|
||
|
case OP_CRMINRANGE:
|
||
|
min = GET2(cc, 1);
|
||
|
cc += 5;
|
||
|
break;
|
||
|
|
||
|
default:
|
||
|
min = 1;
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
branchlength += min * d;
|
||
|
break;
|
||
|
|
||
|
case OP_RECURSE:
|
||
|
cs = ce = (uschar *)startcode + GET(cc, 1);
|
||
|
if (cs == NULL) return -2;
|
||
|
do ce += GET(ce, 1); while (*ce == OP_ALT);
|
||
|
if (cc > cs && cc < ce)
|
||
|
had_recurse = TRUE;
|
||
|
else
|
||
|
branchlength += find_minlength(cs, startcode, options);
|
||
|
cc += 1 + LINK_SIZE;
|
||
|
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. */
|
||
|
|
||
|
case OP_UPTO:
|
||
|
case OP_NOTUPTO:
|
||
|
case OP_MINUPTO:
|
||
|
case OP_NOTMINUPTO:
|
||
|
case OP_POSUPTO:
|
||
|
case OP_STAR:
|
||
|
case OP_MINSTAR:
|
||
|
case OP_NOTMINSTAR:
|
||
|
case OP_POSSTAR:
|
||
|
case OP_NOTPOSSTAR:
|
||
|
case OP_QUERY:
|
||
|
case OP_MINQUERY:
|
||
|
case OP_NOTMINQUERY:
|
||
|
case OP_POSQUERY:
|
||
|
case OP_NOTPOSQUERY:
|
||
|
cc += _pcre_OP_lengths[op];
|
||
|
#ifdef SUPPORT_UTF8
|
||
|
if (utf8 && cc[-1] >= 0xc0) cc += _pcre_utf8_table4[cc[-1] & 0x3f];
|
||
|
#endif
|
||
|
break;
|
||
|
|
||
|
/* Skip these, but we need to add in the name length. */
|
||
|
|
||
|
case OP_MARK:
|
||
|
case OP_PRUNE_ARG:
|
||
|
case OP_SKIP_ARG:
|
||
|
case OP_THEN_ARG:
|
||
|
cc += _pcre_OP_lengths[op] + cc[1];
|
||
|
break;
|
||
|
|
||
|
/* For the record, these are the opcodes that are matched by "default":
|
||
|
OP_ACCEPT, OP_CLOSE, OP_COMMIT, OP_FAIL, OP_PRUNE, OP_SET_SOM, OP_SKIP,
|
||
|
OP_THEN. */
|
||
|
|
||
|
default:
|
||
|
cc += _pcre_OP_lengths[op];
|
||
|
break;
|
||
|
}
|
||
|
}
|
||
|
/* Control never gets here */
|
||
|
}
|
||
|
|
||
|
|
||
|
|
||
|
/*************************************************
|
||
|
* Set a bit and maybe its alternate case *
|
||
|
*************************************************/
|
||
|
|
||
|
/* Given a character, set its first byte's bit in the table, and also the
|
||
|
corresponding bit for the other version of a letter if we are caseless. In
|
||
|
UTF-8 mode, for characters greater than 127, we can only do the caseless thing
|
||
|
when Unicode property support is available.
|
||
|
|
||
|
Arguments:
|
||
|
start_bits points to the bit map
|
||
|
p points to the character
|
||
|
caseless the caseless flag
|
||
|
cd the block with char table pointers
|
||
|
utf8 TRUE for UTF-8 mode
|
||
|
|
||
|
Returns: pointer after the character
|
||
|
*/
|
||
|
|
||
|
static const uschar *
|
||
|
set_table_bit(uschar *start_bits, const uschar *p, BOOL caseless,
|
||
|
compile_data *cd, BOOL utf8)
|
||
|
{
|
||
|
unsigned int c = *p;
|
||
|
|
||
|
SET_BIT(c);
|
||
|
|
||
|
#ifdef SUPPORT_UTF8
|
||
|
if (utf8 && c > 127)
|
||
|
{
|
||
|
GETCHARINC(c, p);
|
||
|
#ifdef SUPPORT_UCP
|
||
|
if (caseless)
|
||
|
{
|
||
|
uschar buff[8];
|
||
|
c = UCD_OTHERCASE(c);
|
||
|
(void)_pcre_ord2utf8(c, buff);
|
||
|
SET_BIT(buff[0]);
|
||
|
}
|
||
|
#endif
|
||
|
return p;
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
/* Not UTF-8 mode, or character is less than 127. */
|
||
|
|
||
|
if (caseless && (cd->ctypes[c] & ctype_letter) != 0) SET_BIT(cd->fcc[c]);
|
||
|
return p + 1;
|
||
|
}
|
||
|
|
||
|
|
||
|
|
||
|
/*************************************************
|
||
|
* 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:
|
||
|
start_bits the starting bitmap
|
||
|
cbit type the type of character wanted
|
||
|
table_limit 32 for non-UTF-8; 16 for UTF-8
|
||
|
cd the block with char table pointers
|
||
|
|
||
|
Returns: nothing
|
||
|
*/
|
||
|
|
||
|
static void
|
||
|
set_type_bits(uschar *start_bits, int cbit_type, int table_limit,
|
||
|
compile_data *cd)
|
||
|
{
|
||
|
register int c;
|
||
|
for (c = 0; c < table_limit; c++) start_bits[c] |= cd->cbits[c+cbit_type];
|
||
|
if (table_limit == 32) return;
|
||
|
for (c = 128; c < 256; c++)
|
||
|
{
|
||
|
if ((cd->cbits[c/8] & (1 << (c&7))) != 0)
|
||
|
{
|
||
|
uschar buff[8];
|
||
|
(void)_pcre_ord2utf8(c, buff);
|
||
|
SET_BIT(buff[0]);
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
|
||
|
/*************************************************
|
||
|
* 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:
|
||
|
start_bits the starting bitmap
|
||
|
cbit type the type of character wanted
|
||
|
table_limit 32 for non-UTF-8; 16 for UTF-8
|
||
|
cd the block with char table pointers
|
||
|
|
||
|
Returns: nothing
|
||
|
*/
|
||
|
|
||
|
static void
|
||
|
set_nottype_bits(uschar *start_bits, int cbit_type, int table_limit,
|
||
|
compile_data *cd)
|
||
|
{
|
||
|
register int c;
|
||
|
for (c = 0; c < table_limit; c++) start_bits[c] |= ~cd->cbits[c+cbit_type];
|
||
|
if (table_limit != 32) for (c = 24; c < 32; c++) start_bits[c] = 0xff;
|
||
|
}
|
||
|
|
||
|
|
||
|
|
||
|
/*************************************************
|
||
|
* Create bitmap of starting bytes *
|
||
|
*************************************************/
|
||
|
|
||
|
/* This function scans a compiled unanchored expression recursively and
|
||
|
attempts to build a bitmap of the set of possible starting bytes. As time goes
|
||
|
by, we may be able to get more clever at doing this. The SSB_CONTINUE return is
|
||
|
useful for parenthesized groups in patterns such as (a*)b where the group
|
||
|
provides some optional starting bytes but scanning must continue at the outer
|
||
|
level to find at least one mandatory byte. At the outermost level, this
|
||
|
function fails unless the result is SSB_DONE.
|
||
|
|
||
|
Arguments:
|
||
|
code points to an expression
|
||
|
start_bits points to a 32-byte table, initialized to 0
|
||
|
caseless the current state of the caseless flag
|
||
|
utf8 TRUE if in UTF-8 mode
|
||
|
cd the block with char table pointers
|
||
|
|
||
|
Returns: SSB_FAIL => Failed to find any starting bytes
|
||
|
SSB_DONE => Found mandatory starting bytes
|
||
|
SSB_CONTINUE => Found optional starting bytes
|
||
|
*/
|
||
|
|
||
|
static int
|
||
|
set_start_bits(const uschar *code, uschar *start_bits, BOOL caseless,
|
||
|
BOOL utf8, compile_data *cd)
|
||
|
{
|
||
|
register int c;
|
||
|
int yield = SSB_DONE;
|
||
|
int table_limit = utf8? 16:32;
|
||
|
|
||
|
#if 0
|
||
|
/* ========================================================================= */
|
||
|
/* The following comment and code was inserted in January 1999. In May 2006,
|
||
|
when it was observed to cause compiler warnings about unused values, I took it
|
||
|
out again. If anybody is still using OS/2, they will have to put it back
|
||
|
manually. */
|
||
|
|
||
|
/* This next statement and the later reference to dummy are here in order to
|
||
|
trick the optimizer of the IBM C compiler for OS/2 into generating correct
|
||
|
code. Apparently IBM isn't going to fix the problem, and we would rather not
|
||
|
disable optimization (in this module it actually makes a big difference, and
|
||
|
the pcre module can use all the optimization it can get). */
|
||
|
|
||
|
volatile int dummy;
|
||
|
/* ========================================================================= */
|
||
|
#endif
|
||
|
|
||
|
do
|
||
|
{
|
||
|
const uschar *tcode = code + (((int)*code == OP_CBRA)? 3:1) + LINK_SIZE;
|
||
|
BOOL try_next = TRUE;
|
||
|
|
||
|
while (try_next) /* Loop for items in this branch */
|
||
|
{
|
||
|
int rc;
|
||
|
switch(*tcode)
|
||
|
{
|
||
|
/* Fail if we reach something we don't understand */
|
||
|
|
||
|
default:
|
||
|
return SSB_FAIL;
|
||
|
|
||
|
/* If we hit a bracket or a positive lookahead assertion, 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_ONCE:
|
||
|
case OP_ASSERT:
|
||
|
rc = set_start_bits(tcode, start_bits, caseless, utf8, cd);
|
||
|
if (rc == SSB_FAIL) return SSB_FAIL;
|
||
|
if (rc == SSB_DONE) try_next = FALSE; else
|
||
|
{
|
||
|
do tcode += GET(tcode, 1); while (*tcode == OP_ALT);
|
||
|
tcode += 1 + LINK_SIZE;
|
||
|
}
|
||
|
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:
|
||
|
return SSB_CONTINUE;
|
||
|
|
||
|
/* Skip over callout */
|
||
|
|
||
|
case OP_CALLOUT:
|
||
|
tcode += 2 + 2*LINK_SIZE;
|
||
|
break;
|
||
|
|
||
|
/* Skip over lookbehind and negative lookahead assertions */
|
||
|
|
||
|
case OP_ASSERT_NOT:
|
||
|
case OP_ASSERTBACK:
|
||
|
case OP_ASSERTBACK_NOT:
|
||
|
do tcode += GET(tcode, 1); while (*tcode == OP_ALT);
|
||
|
tcode += 1 + LINK_SIZE;
|
||
|
break;
|
||
|
|
||
|
/* Skip over an option setting, changing the caseless flag */
|
||
|
|
||
|
case OP_OPT:
|
||
|
caseless = (tcode[1] & PCRE_CASELESS) != 0;
|
||
|
tcode += 2;
|
||
|
break;
|
||
|
|
||
|
/* BRAZERO does the bracket, but carries on. */
|
||
|
|
||
|
case OP_BRAZERO:
|
||
|
case OP_BRAMINZERO:
|
||
|
if (set_start_bits(++tcode, start_bits, caseless, utf8, cd) == SSB_FAIL)
|
||
|
return SSB_FAIL;
|
||
|
/* =========================================================================
|
||
|
See the comment at the head of this function concerning the next line,
|
||
|
which was an old fudge for the benefit of OS/2.
|
||
|
dummy = 1;
|
||
|
========================================================================= */
|
||
|
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(start_bits, tcode + 1, caseless, cd, utf8);
|
||
|
break;
|
||
|
|
||
|
/* Single-char upto sets the bit and tries the next */
|
||
|
|
||
|
case OP_UPTO:
|
||
|
case OP_MINUPTO:
|
||
|
case OP_POSUPTO:
|
||
|
tcode = set_table_bit(start_bits, tcode + 3, caseless, cd, utf8);
|
||
|
break;
|
||
|
|
||
|
/* At least one single char sets the bit and stops */
|
||
|
|
||
|
case OP_EXACT: /* Fall through */
|
||
|
tcode += 2;
|
||
|
|
||
|
case OP_CHAR:
|
||
|
case OP_CHARNC:
|
||
|
case OP_PLUS:
|
||
|
case OP_MINPLUS:
|
||
|
case OP_POSPLUS:
|
||
|
(void)set_table_bit(start_bits, tcode + 1, caseless, cd, utf8);
|
||
|
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(0x09);
|
||
|
SET_BIT(0x20);
|
||
|
if (utf8)
|
||
|
{
|
||
|
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 SET_BIT(0xA0);
|
||
|
try_next = FALSE;
|
||
|
break;
|
||
|
|
||
|
case OP_ANYNL:
|
||
|
case OP_VSPACE:
|
||
|
SET_BIT(0x0A);
|
||
|
SET_BIT(0x0B);
|
||
|
SET_BIT(0x0C);
|
||
|
SET_BIT(0x0D);
|
||
|
if (utf8)
|
||
|
{
|
||
|
SET_BIT(0xC2); /* For U+0085 */
|
||
|
SET_BIT(0xE2); /* For U+2028, U+2029 */
|
||
|
}
|
||
|
else SET_BIT(0x85);
|
||
|
try_next = FALSE;
|
||
|
break;
|
||
|
|
||
|
/* Single character types set the bits and stop. Note that if PCRE_UCP
|
||
|
is set, we do not see these op codes 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(start_bits, cbit_digit, table_limit, cd);
|
||
|
try_next = FALSE;
|
||
|
break;
|
||
|
|
||
|
case OP_DIGIT:
|
||
|
set_type_bits(start_bits, cbit_digit, table_limit, cd);
|
||
|
try_next = FALSE;
|
||
|
break;
|
||
|
|
||
|
/* The cbit_space table has vertical tab as whitespace; we have to
|
||
|
ensure it is set as not whitespace. */
|
||
|
|
||
|
case OP_NOT_WHITESPACE:
|
||
|
set_nottype_bits(start_bits, cbit_space, table_limit, cd);
|
||
|
start_bits[1] |= 0x08;
|
||
|
try_next = FALSE;
|
||
|
break;
|
||
|
|
||
|
/* The cbit_space table has vertical tab as whitespace; we have to
|
||
|
not set it from the table. */
|
||
|
|
||
|
case OP_WHITESPACE:
|
||
|
c = start_bits[1]; /* Save in case it was already set */
|
||
|
set_type_bits(start_bits, cbit_space, table_limit, cd);
|
||
|
start_bits[1] = (start_bits[1] & ~0x08) | c;
|
||
|
try_next = FALSE;
|
||
|
break;
|
||
|
|
||
|
case OP_NOT_WORDCHAR:
|
||
|
set_nottype_bits(start_bits, cbit_word, table_limit, cd);
|
||
|
try_next = FALSE;
|
||
|
break;
|
||
|
|
||
|
case OP_WORDCHAR:
|
||
|
set_type_bits(start_bits, cbit_word, table_limit, cd);
|
||
|
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 += 3;
|
||
|
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 += 2; /* 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(0x09);
|
||
|
SET_BIT(0x20);
|
||
|
if (utf8)
|
||
|
{
|
||
|
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 SET_BIT(0xA0);
|
||
|
break;
|
||
|
|
||
|
case OP_ANYNL:
|
||
|
case OP_VSPACE:
|
||
|
SET_BIT(0x0A);
|
||
|
SET_BIT(0x0B);
|
||
|
SET_BIT(0x0C);
|
||
|
SET_BIT(0x0D);
|
||
|
if (utf8)
|
||
|
{
|
||
|
SET_BIT(0xC2); /* For U+0085 */
|
||
|
SET_BIT(0xE2); /* For U+2028, U+2029 */
|
||
|
}
|
||
|
else SET_BIT(0x85);
|
||
|
break;
|
||
|
|
||
|
case OP_NOT_DIGIT:
|
||
|
set_nottype_bits(start_bits, cbit_digit, table_limit, cd);
|
||
|
break;
|
||
|
|
||
|
case OP_DIGIT:
|
||
|
set_type_bits(start_bits, cbit_digit, table_limit, cd);
|
||
|
break;
|
||
|
|
||
|
/* The cbit_space table has vertical tab as whitespace; we have to
|
||
|
ensure it gets set as not whitespace. */
|
||
|
|
||
|
case OP_NOT_WHITESPACE:
|
||
|
set_nottype_bits(start_bits, cbit_space, table_limit, cd);
|
||
|
start_bits[1] |= 0x08;
|
||
|
break;
|
||
|
|
||
|
/* The cbit_space table has vertical tab as whitespace; we have to
|
||
|
avoid setting it. */
|
||
|
|
||
|
case OP_WHITESPACE:
|
||
|
c = start_bits[1]; /* Save in case it was already set */
|
||
|
set_type_bits(start_bits, cbit_space, table_limit, cd);
|
||
|
start_bits[1] = (start_bits[1] & ~0x08) | c;
|
||
|
break;
|
||
|
|
||
|
case OP_NOT_WORDCHAR:
|
||
|
set_nottype_bits(start_bits, cbit_word, table_limit, cd);
|
||
|
break;
|
||
|
|
||
|
case OP_WORDCHAR:
|
||
|
set_type_bits(start_bits, cbit_word, table_limit, cd);
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
tcode += 2;
|
||
|
break;
|
||
|
|
||
|
/* Character class where all the information is in a bit map: set the
|
||
|
bits and either carry on or not, according to the repeat count. If it was
|
||
|
a negative class, and we are operating with UTF-8 characters, any byte
|
||
|
with a value >= 0xc4 is a potentially valid starter because it starts a
|
||
|
character with a value > 255. */
|
||
|
|
||
|
case OP_NCLASS:
|
||
|
#ifdef SUPPORT_UTF8
|
||
|
if (utf8)
|
||
|
{
|
||
|
start_bits[24] |= 0xf0; /* Bits for 0xc4 - 0xc8 */
|
||
|
memset(start_bits+25, 0xff, 7); /* Bits for 0xc9 - 0xff */
|
||
|
}
|
||
|
#endif
|
||
|
/* Fall through */
|
||
|
|
||
|
case OP_CLASS:
|
||
|
{
|
||
|
tcode++;
|
||
|
|
||
|
/* In UTF-8 mode, the bits in a 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
|
||
|
value is > 127. In fact, there are only two possible starting bytes for
|
||
|
characters in the range 128 - 255. */
|
||
|
|
||
|
#ifdef SUPPORT_UTF8
|
||
|
if (utf8)
|
||
|
{
|
||
|
for (c = 0; c < 16; c++) start_bits[c] |= tcode[c];
|
||
|
for (c = 128; c < 256; c++)
|
||
|
{
|
||
|
if ((tcode[c/8] && (1 << (c&7))) != 0)
|
||
|
{
|
||
|
int d = (c >> 6) | 0xc0; /* Set bit for this starter */
|
||
|
start_bits[d/8] |= (1 << (d&7)); /* and then skip on to the */
|
||
|
c = (c & 0xc0) + 0x40 - 1; /* next relevant character. */
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* In non-UTF-8 mode, the two bit maps are completely compatible. */
|
||
|
|
||
|
else
|
||
|
#endif
|
||
|
{
|
||
|
for (c = 0; c < 32; c++) start_bits[c] |= tcode[c];
|
||
|
}
|
||
|
|
||
|
/* Advance past the bit map, and act on what follows */
|
||
|
|
||
|
tcode += 32;
|
||
|
switch (*tcode)
|
||
|
{
|
||
|
case OP_CRSTAR:
|
||
|
case OP_CRMINSTAR:
|
||
|
case OP_CRQUERY:
|
||
|
case OP_CRMINQUERY:
|
||
|
tcode++;
|
||
|
break;
|
||
|
|
||
|
case OP_CRRANGE:
|
||
|
case OP_CRMINRANGE:
|
||
|
if (((tcode[1] << 8) + tcode[2]) == 0) tcode += 5;
|
||
|
else try_next = FALSE;
|
||
|
break;
|
||
|
|
||
|
default:
|
||
|
try_next = FALSE;
|
||
|
break;
|
||
|
}
|
||
|
}
|
||
|
break; /* End of bitmap class handling */
|
||
|
|
||
|
} /* End of switch */
|
||
|
} /* 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. It returns a pcre_extra block
|
||
|
which then gets handed back to pcre_exec().
|
||
|
|
||
|
Arguments:
|
||
|
re points to the compiled expression
|
||
|
options contains option bits
|
||
|
errorptr points to where to place error messages;
|
||
|
set NULL unless error
|
||
|
|
||
|
Returns: pointer to a pcre_extra block, with study_data filled in and the
|
||
|
appropriate flags set;
|
||
|
NULL on error or if no optimization possible
|
||
|
*/
|
||
|
|
||
|
PCRE_EXP_DEFN pcre_extra * PCRE_CALL_CONVENTION
|
||
|
pcre_study(const pcre *external_re, int options, const char **errorptr)
|
||
|
{
|
||
|
int min;
|
||
|
BOOL bits_set = FALSE;
|
||
|
uschar start_bits[32];
|
||
|
pcre_extra *extra;
|
||
|
pcre_study_data *study;
|
||
|
const uschar *tables;
|
||
|
uschar *code;
|
||
|
compile_data compile_block;
|
||
|
const real_pcre *re = (const real_pcre *)external_re;
|
||
|
|
||
|
*errorptr = NULL;
|
||
|
|
||
|
if (re == NULL || re->magic_number != MAGIC_NUMBER)
|
||
|
{
|
||
|
*errorptr = "argument is not a compiled regular expression";
|
||
|
return NULL;
|
||
|
}
|
||
|
|
||
|
if ((options & ~PUBLIC_STUDY_OPTIONS) != 0)
|
||
|
{
|
||
|
*errorptr = "unknown or incorrect option bit(s) set";
|
||
|
return NULL;
|
||
|
}
|
||
|
|
||
|
code = (uschar *)re + re->name_table_offset +
|
||
|
(re->name_count * re->name_entry_size);
|
||
|
|
||
|
/* For an anchored pattern, or an unanchored pattern that has a first char, or
|
||
|
a multiline pattern that matches only at "line starts", there is no point in
|
||
|
seeking a list of starting bytes. */
|
||
|
|
||
|
if ((re->options & PCRE_ANCHORED) == 0 &&
|
||
|
(re->flags & (PCRE_FIRSTSET|PCRE_STARTLINE)) == 0)
|
||
|
{
|
||
|
/* Set the character tables in the block that is passed around */
|
||
|
|
||
|
tables = re->tables;
|
||
|
if (tables == NULL)
|
||
|
(void)pcre_fullinfo(external_re, NULL, PCRE_INFO_DEFAULT_TABLES,
|
||
|
(void *)(&tables));
|
||
|
|
||
|
compile_block.lcc = tables + lcc_offset;
|
||
|
compile_block.fcc = tables + fcc_offset;
|
||
|
compile_block.cbits = tables + cbits_offset;
|
||
|
compile_block.ctypes = tables + ctypes_offset;
|
||
|
|
||
|
/* See if we can find a fixed set of initial characters for the pattern. */
|
||
|
|
||
|
memset(start_bits, 0, 32 * sizeof(uschar));
|
||
|
bits_set = set_start_bits(code, start_bits,
|
||
|
(re->options & PCRE_CASELESS) != 0, (re->options & PCRE_UTF8) != 0,
|
||
|
&compile_block) == SSB_DONE;
|
||
|
}
|
||
|
|
||
|
/* Find the minimum length of subject string. */
|
||
|
|
||
|
min = find_minlength(code, code, re->options);
|
||
|
|
||
|
/* Return NULL if no optimization is possible. */
|
||
|
|
||
|
if (!bits_set && min < 0) return NULL;
|
||
|
|
||
|
/* Get a pcre_extra block and a pcre_study_data block. The study data is put in
|
||
|
the latter, which is pointed to by the former, which may also get additional
|
||
|
data set later by the calling program. At the moment, the size of
|
||
|
pcre_study_data is fixed. We nevertheless save it in a field for returning via
|
||
|
the pcre_fullinfo() function so that if it becomes variable in the future, we
|
||
|
don't have to change that code. */
|
||
|
|
||
|
extra = (pcre_extra *)(pcre_malloc)
|
||
|
(sizeof(pcre_extra) + sizeof(pcre_study_data));
|
||
|
|
||
|
if (extra == NULL)
|
||
|
{
|
||
|
*errorptr = "failed to get memory";
|
||
|
return NULL;
|
||
|
}
|
||
|
|
||
|
study = (pcre_study_data *)((char *)extra + sizeof(pcre_extra));
|
||
|
extra->flags = PCRE_EXTRA_STUDY_DATA;
|
||
|
extra->study_data = study;
|
||
|
|
||
|
study->size = sizeof(pcre_study_data);
|
||
|
study->flags = 0;
|
||
|
|
||
|
if (bits_set)
|
||
|
{
|
||
|
study->flags |= PCRE_STUDY_MAPPED;
|
||
|
memcpy(study->start_bits, start_bits, sizeof(start_bits));
|
||
|
}
|
||
|
|
||
|
if (min >= 0)
|
||
|
{
|
||
|
study->flags |= PCRE_STUDY_MINLEN;
|
||
|
study->minlength = min;
|
||
|
}
|
||
|
|
||
|
return extra;
|
||
|
}
|
||
|
|
||
|
/* End of pcre_study.c */
|