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+/*************************************************
+* 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
+ Copyright (c) 1997-2012 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 the external function pcre_study(), along with local
+supporting functions. */
+
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "pcre_internal.h"
+
+#define SET_BIT(c) start_bits[c/8] |= (1 << (c&7))
+
+/* Returns from set_start_bits() */
+
+enum { SSB_FAIL, SSB_DONE, SSB_CONTINUE, SSB_UNKNOWN };
+
+
+
+/*************************************************
+* 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 UTF8 mode, the result is in characters
+rather than bytes.
+
+Arguments:
+ re compiled pattern block
+ code pointer to start of group (the bracket)
+ startcode pointer to start of the whole pattern's code
+ options the compiling options
+ int RECURSE depth
+
+Returns: the minimum length
+ -1 if \C in UTF-8 mode or (*ACCEPT) was encountered
+ -2 internal error (missing capturing bracket)
+ -3 internal error (opcode not listed)
+*/
+
+static int
+find_minlength(const REAL_PCRE *re, const pcre_uchar *code,
+ const pcre_uchar *startcode, int options, int recurse_depth)
+{
+int length = -1;
+/* PCRE_UTF16 has the same value as PCRE_UTF8. */
+BOOL utf = (options & PCRE_UTF8) != 0;
+BOOL had_recurse = FALSE;
+register int branchlength = 0;
+register pcre_uchar *cc = (pcre_uchar *)code + 1 + LINK_SIZE;
+
+if (*code == OP_CBRA || *code == OP_SCBRA ||
+ *code == OP_CBRAPOS || *code == OP_SCBRAPOS) cc += IMM2_SIZE;
+
+/* 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. */
+
+for (;;)
+ {
+ int d, min;
+ pcre_uchar *cs, *ce;
+ register pcre_uchar 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. */
+
+ cs = cc + GET(cc, 1);
+ if (*cs != OP_ALT)
+ {
+ cc = cs + 1 + LINK_SIZE;
+ break;
+ }
+
+ /* Otherwise we can fall through and treat it the same as any other
+ subpattern. */
+
+ case OP_CBRA:
+ case OP_SCBRA:
+ case OP_BRA:
+ case OP_SBRA:
+ case OP_CBRAPOS:
+ case OP_SCBRAPOS:
+ case OP_BRAPOS:
+ case OP_SBRAPOS:
+ case OP_ONCE:
+ case OP_ONCE_NC:
+ d = find_minlength(re, cc, startcode, options, recurse_depth);
+ if (d < 0) return d;
+ branchlength += 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. */
+
+ 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 an
+ ACCEPT was previously encountered, use the length that was in force at that
+ time, and pass back the shortest ACCEPT length. */
+
+ 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) return length;
+ 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:
+ do cc += GET(cc, 1); while (*cc == OP_ALT);
+ /* Fall through */
+
+ /* Skip over things that don't match chars */
+
+ case OP_REVERSE:
+ case OP_CREF:
+ case OP_DNCREF:
+ case OP_RREF:
+ case OP_DNRREF:
+ case OP_DEF:
+ 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:
+ cc += PRIV(OP_lengths)[*cc];
+ 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_UTF
+ 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
+ need to skip over a multibyte character in UTF8 mode. */
+
+ case OP_EXACT:
+ case OP_EXACTI:
+ case OP_NOTEXACT:
+ case OP_NOTEXACTI:
+ branchlength += GET2(cc,1);
+ cc += 2 + IMM2_SIZE;
+#ifdef SUPPORT_UTF
+ 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-8 mode. (In
+ non-UTF-8 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_UTF
+ 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:
+#if defined SUPPORT_UTF || defined COMPILE_PCRE16 || defined COMPILE_PCRE32
+ 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 are treated in the same way: we find
+ 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_DNREF: /* Duplicate named pattern back reference */
+ case OP_DNREFI:
+ if ((options & PCRE_JAVASCRIPT_COMPAT) == 0)
+ {
+ int count = GET2(cc, 1+IMM2_SIZE);
+ pcre_uchar *slot = (pcre_uchar *)re +
+ re->name_table_offset + GET2(cc, 1) * re->name_entry_size;
+ d = INT_MAX;
+ while (count-- > 0)
+ {
+ ce = cs = (pcre_uchar *)PRIV(find_bracket)(startcode, utf, GET2(slot, 0));
+ if (cs == NULL) return -2;
+ do ce += GET(ce, 1); while (*ce == OP_ALT);
+ if (cc > cs && cc < ce)
+ {
+ d = 0;
+ had_recurse = TRUE;
+ break;
+ }
+ else
+ {
+ int dd = find_minlength(re, cs, startcode, options, recurse_depth);
+ if (dd < d) d = dd;
+ }
+ slot += re->name_entry_size;
+ }
+ }
+ else d = 0;
+ cc += 1 + 2*IMM2_SIZE;
+ goto REPEAT_BACK_REFERENCE;
+
+ case OP_REF: /* Single back reference */
+ case OP_REFI:
+ if ((options & PCRE_JAVASCRIPT_COMPAT) == 0)
+ {
+ ce = cs = (pcre_uchar *)PRIV(find_bracket)(startcode, utf, 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(re, cs, startcode, options, recurse_depth);
+ }
+ }
+ else d = 0;
+ 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;
+ }
+
+ branchlength += min * d;
+ break;
+
+ /* We can easily detect direct recursion, but not mutual recursion. This is
+ caught by a recursion depth count. */
+
+ case OP_RECURSE:
+ cs = ce = (pcre_uchar *)startcode + GET(cc, 1);
+ do ce += GET(ce, 1); while (*ce == OP_ALT);
+ if ((cc > cs && cc < ce) || recurse_depth > 10)
+ had_recurse = TRUE;
+ else
+ {
+ branchlength += find_minlength(re, cs, startcode, options,
+ recurse_depth + 1);
+ }
+ 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. 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_UTF
+ 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_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 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
+ utf TRUE for UTF-8 / UTF-16 / UTF-32 mode
+
+Returns: pointer after the character
+*/
+
+static const pcre_uchar *
+set_table_bit(pcre_uint8 *start_bits, const pcre_uchar *p, BOOL caseless,
+ compile_data *cd, BOOL utf)
+{
+pcre_uint32 c = *p;
+
+#ifdef COMPILE_PCRE8
+SET_BIT(c);
+
+#ifdef SUPPORT_UTF
+if (utf && c > 127)
+ {
+ GETCHARINC(c, p);
+#ifdef SUPPORT_UCP
+ if (caseless)
+ {
+ pcre_uchar buff[6];
+ c = UCD_OTHERCASE(c);
+ (void)PRIV(ord2utf)(c, buff);
+ SET_BIT(buff[0]);
+ }
+#endif /* Not SUPPORT_UCP */
+ return p;
+ }
+#else /* Not SUPPORT_UTF */
+(void)(utf); /* Stops warning for unused parameter */
+#endif /* SUPPORT_UTF */
+
+/* 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;
+#endif /* COMPILE_PCRE8 */
+
+#if defined COMPILE_PCRE16 || defined COMPILE_PCRE32
+if (c > 0xff)
+ {
+ c = 0xff;
+ caseless = FALSE;
+ }
+SET_BIT(c);
+
+#ifdef SUPPORT_UTF
+if (utf && c > 127)
+ {
+ GETCHARINC(c, p);
+#ifdef SUPPORT_UCP
+ if (caseless)
+ {
+ c = UCD_OTHERCASE(c);
+ if (c > 0xff)
+ c = 0xff;
+ SET_BIT(c);
+ }
+#endif /* SUPPORT_UCP */
+ return p;
+ }
+#else /* Not SUPPORT_UTF */
+(void)(utf); /* Stops warning for unused parameter */
+#endif /* SUPPORT_UTF */
+
+if (caseless && (cd->ctypes[c] & ctype_letter) != 0) SET_BIT(cd->fcc[c]);
+return p + 1;
+#endif
+}
+
+
+
+/*************************************************
+* 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(pcre_uint8 *start_bits, int cbit_type, unsigned int table_limit,
+ compile_data *cd)
+{
+register pcre_uint32 c;
+for (c = 0; c < table_limit; c++) start_bits[c] |= cd->cbits[c+cbit_type];
+#if defined SUPPORT_UTF && defined COMPILE_PCRE8
+if (table_limit == 32) return;
+for (c = 128; c < 256; c++)
+ {
+ if ((cd->cbits[c/8] & (1 << (c&7))) != 0)
+ {
+ pcre_uchar buff[6];
+ (void)PRIV(ord2utf)(c, buff);
+ SET_BIT(buff[0]);
+ }
+ }
+#endif
+}
+
+
+/*************************************************
+* 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(pcre_uint8 *start_bits, int cbit_type, unsigned int table_limit,
+ compile_data *cd)
+{
+register pcre_uint32 c;
+for (c = 0; c < table_limit; c++) start_bits[c] |= ~cd->cbits[c+cbit_type];
+#if defined SUPPORT_UTF && defined COMPILE_PCRE8
+if (table_limit != 32) for (c = 24; c < 32; c++) start_bits[c] = 0xff;
+#endif
+}
+
+
+
+/*************************************************
+* 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
+ utf TRUE if in UTF-8 / UTF-16 / UTF-32 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
+ SSB_UNKNOWN => Hit an unrecognized opcode
+*/
+
+static int
+set_start_bits(const pcre_uchar *code, pcre_uint8 *start_bits, BOOL utf,
+ compile_data *cd)
+{
+register pcre_uint32 c;
+int yield = SSB_DONE;
+#if defined SUPPORT_UTF && defined COMPILE_PCRE8
+int table_limit = utf? 16:32;
+#else
+int table_limit = 32;
+#endif
+
+#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
+ {
+ BOOL try_next = TRUE;
+ const pcre_uchar *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;
+
+ 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 code. 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_CIRC:
+ case OP_CIRCM:
+ case OP_CLOSE:
+ case OP_COMMIT:
+ case OP_COND:
+ case OP_CREF:
+ case OP_DEF:
+ 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_PROP:
+ case OP_PRUNE:
+ case OP_PRUNE_ARG:
+ case OP_RECURSE:
+ case OP_REF:
+ case OP_REFI:
+ case OP_REVERSE:
+ 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;
+
+ /* We can ignore word boundary tests. */
+
+ case OP_WORD_BOUNDARY:
+ case OP_NOT_WORD_BOUNDARY:
+ tcode++;
+ break;
+
+ /* 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_BRAPOS:
+ case OP_SBRAPOS:
+ case OP_CBRAPOS:
+ case OP_SCBRAPOS:
+ case OP_ONCE:
+ case OP_ONCE_NC:
+ case OP_ASSERT:
+ rc = set_start_bits(tcode, start_bits, utf, cd);
+ if (rc == SSB_FAIL || rc == SSB_UNKNOWN) return rc;
+ 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:
+ case OP_KETRPOS:
+ 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;
+
+ /* BRAZERO does the bracket, but carries on. */
+
+ case OP_BRAZERO:
+ case OP_BRAMINZERO:
+ case OP_BRAPOSZERO:
+ rc = set_start_bits(++tcode, start_bits, utf, cd);
+ if (rc == SSB_FAIL || rc == SSB_UNKNOWN) return rc;
+/* =========================================================================
+ 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, FALSE, cd, utf);
+ break;
+
+ case OP_STARI:
+ case OP_MINSTARI:
+ case OP_POSSTARI:
+ case OP_QUERYI:
+ case OP_MINQUERYI:
+ case OP_POSQUERYI:
+ tcode = set_table_bit(start_bits, tcode + 1, TRUE, cd, utf);
+ 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 + 1 + IMM2_SIZE, FALSE, cd, utf);
+ break;
+
+ case OP_UPTOI:
+ case OP_MINUPTOI:
+ case OP_POSUPTOI:
+ tcode = set_table_bit(start_bits, tcode + 1 + IMM2_SIZE, TRUE, cd, utf);
+ 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(start_bits, tcode + 1, FALSE, cd, utf);
+ 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(start_bits, tcode + 1, TRUE, cd, utf);
+ 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);
+#ifdef SUPPORT_UTF
+ if (utf)
+ {
+#ifdef COMPILE_PCRE8
+ 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 */
+#elif defined COMPILE_PCRE16 || defined COMPILE_PCRE32
+ SET_BIT(0xA0);
+ SET_BIT(0xFF); /* For characters > 255 */
+#endif /* COMPILE_PCRE[8|16|32] */
+ }
+ else
+#endif /* SUPPORT_UTF */
+ {
+#ifndef EBCDIC
+ SET_BIT(0xA0);
+#endif /* Not EBCDIC */
+#if defined COMPILE_PCRE16 || defined COMPILE_PCRE32
+ SET_BIT(0xFF); /* For characters > 255 */
+#endif /* COMPILE_PCRE[16|32] */
+ }
+ 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);
+#ifdef SUPPORT_UTF
+ if (utf)
+ {
+#ifdef COMPILE_PCRE8
+ SET_BIT(0xC2); /* For U+0085 */
+ SET_BIT(0xE2); /* For U+2028, U+2029 */
+#elif defined COMPILE_PCRE16 || defined COMPILE_PCRE32
+ SET_BIT(CHAR_NEL);
+ SET_BIT(0xFF); /* For characters > 255 */
+#endif /* COMPILE_PCRE[8|16|32] */
+ }
+ else
+#endif /* SUPPORT_UTF */
+ {
+ SET_BIT(CHAR_NEL);
+#if defined COMPILE_PCRE16 || defined COMPILE_PCRE32
+ SET_BIT(0xFF); /* For characters > 255 */
+#endif
+ }
+ 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. Luckily, the code value is the same
+ (0x0b) in ASCII and EBCDIC, so we can just adjust the appropriate bit. */
+
+ 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. Luckily, the code value is the same (0x0b) in
+ ASCII and EBCDIC, so we can just adjust the appropriate bit. */
+
+ 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 += 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);
+#ifdef SUPPORT_UTF
+ if (utf)
+ {
+#ifdef COMPILE_PCRE8
+ 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 */
+#elif defined COMPILE_PCRE16 || defined COMPILE_PCRE32
+ SET_BIT(0xA0);
+ SET_BIT(0xFF); /* For characters > 255 */
+#endif /* COMPILE_PCRE[8|16|32] */
+ }
+ else
+#endif /* SUPPORT_UTF */
+#ifndef EBCDIC
+ SET_BIT(0xA0);
+#endif /* Not EBCDIC */
+ break;
+
+ case OP_ANYNL:
+ case OP_VSPACE:
+ SET_BIT(CHAR_LF);
+ SET_BIT(CHAR_VT);
+ SET_BIT(CHAR_FF);
+ SET_BIT(CHAR_CR);
+#ifdef SUPPORT_UTF
+ if (utf)
+ {
+#ifdef COMPILE_PCRE8
+ SET_BIT(0xC2); /* For U+0085 */
+ SET_BIT(0xE2); /* For U+2028, U+2029 */
+#elif defined COMPILE_PCRE16 || defined COMPILE_PCRE32
+ SET_BIT(CHAR_NEL);
+ SET_BIT(0xFF); /* For characters > 255 */
+#endif /* COMPILE_PCRE16 */
+ }
+ else
+#endif /* SUPPORT_UTF */
+ SET_BIT(CHAR_NEL);
+ 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 no longer
+ have to play fancy tricks because Perl added VT to its whitespace at
+ release 5.18. PCRE added it at release 8.34. */
+
+ case OP_NOT_WHITESPACE:
+ set_nottype_bits(start_bits, cbit_space, table_limit, cd);
+ break;
+
+ case OP_WHITESPACE:
+ set_type_bits(start_bits, cbit_space, table_limit, cd);
+ 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. */
+
+#if defined SUPPORT_UTF || !defined COMPILE_PCRE8
+ case OP_XCLASS:
+ if ((tcode[1 + LINK_SIZE] & XCL_HASPROP) != 0)
+ return SSB_FAIL;
+ /* All bits are set. */
+ if ((tcode[1 + LINK_SIZE] & XCL_MAP) == 0 && (tcode[1 + LINK_SIZE] & XCL_NOT) != 0)
+ return SSB_FAIL;
+#endif
+ /* Fall through */
+
+ case OP_NCLASS:
+#if defined SUPPORT_UTF && defined COMPILE_PCRE8
+ if (utf)
+ {
+ start_bits[24] |= 0xf0; /* Bits for 0xc4 - 0xc8 */
+ memset(start_bits+25, 0xff, 7); /* Bits for 0xc9 - 0xff */
+ }
+#endif
+#if defined COMPILE_PCRE16 || defined COMPILE_PCRE32
+ SET_BIT(0xFF); /* For characters > 255 */
+#endif
+ /* Fall through */
+
+ case OP_CLASS:
+ {
+ pcre_uint8 *map;
+#if defined SUPPORT_UTF || !defined COMPILE_PCRE8
+ map = NULL;
+ if (*tcode == OP_XCLASS)
+ {
+ if ((tcode[1 + LINK_SIZE] & XCL_MAP) != 0)
+ map = (pcre_uint8 *)(tcode + 1 + LINK_SIZE + 1);
+ tcode += GET(tcode, 1);
+ }
+ else
+#endif
+ {
+ tcode++;
+ map = (pcre_uint8 *)tcode;
+ tcode += 32 / sizeof(pcre_uchar);
+ }
+
+ /* 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. */
+
+#if defined SUPPORT_UTF || !defined COMPILE_PCRE8
+ if (map != NULL)
+#endif
+ {
+#if defined SUPPORT_UTF && defined COMPILE_PCRE8
+ if (utf)
+ {
+ for (c = 0; c < 16; c++) start_bits[c] |= map[c];
+ for (c = 128; c < 256; c++)
+ {
+ if ((map[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. */
+ }
+ }
+ }
+ else
+#endif
+ {
+ /* In non-UTF-8 mode, the two bit maps are completely compatible. */
+ for (c = 0; c < 32; c++) start_bits[c] |= map[c];
+ }
+ }
+
+ /* Advance past the bit map, and act on what follows. 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 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[16]_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[16]_extra block, with study_data filled in and
+ the appropriate flags set;
+ NULL on error or if no optimization possible
+*/
+
+#if defined COMPILE_PCRE8
+PCRE_EXP_DEFN pcre_extra * PCRE_CALL_CONVENTION
+pcre_study(const pcre *external_re, int options, const char **errorptr)
+#elif defined COMPILE_PCRE16
+PCRE_EXP_DEFN pcre16_extra * PCRE_CALL_CONVENTION
+pcre16_study(const pcre16 *external_re, int options, const char **errorptr)
+#elif defined COMPILE_PCRE32
+PCRE_EXP_DEFN pcre32_extra * PCRE_CALL_CONVENTION
+pcre32_study(const pcre32 *external_re, int options, const char **errorptr)
+#endif
+{
+int min;
+BOOL bits_set = FALSE;
+pcre_uint8 start_bits[32];
+PUBL(extra) *extra = NULL;
+pcre_study_data *study;
+const pcre_uint8 *tables;
+pcre_uchar *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 ((re->flags & PCRE_MODE) == 0)
+ {
+#if defined COMPILE_PCRE8
+ *errorptr = "argument not compiled in 8 bit mode";
+#elif defined COMPILE_PCRE16
+ *errorptr = "argument not compiled in 16 bit mode";
+#elif defined COMPILE_PCRE32
+ *errorptr = "argument not compiled in 32 bit mode";
+#endif
+ return NULL;
+ }
+
+if ((options & ~PUBLIC_STUDY_OPTIONS) != 0)
+ {
+ *errorptr = "unknown or incorrect option bit(s) set";
+ return NULL;
+ }
+
+code = (pcre_uchar *)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)
+ {
+ int rc;
+
+ /* Set the character tables in the block that is passed around */
+
+ tables = re->tables;
+
+#if defined COMPILE_PCRE8
+ if (tables == NULL)
+ (void)pcre_fullinfo(external_re, NULL, PCRE_INFO_DEFAULT_TABLES,
+ (void *)(&tables));
+#elif defined COMPILE_PCRE16
+ if (tables == NULL)
+ (void)pcre16_fullinfo(external_re, NULL, PCRE_INFO_DEFAULT_TABLES,
+ (void *)(&tables));
+#elif defined COMPILE_PCRE32
+ if (tables == NULL)
+ (void)pcre32_fullinfo(external_re, NULL, PCRE_INFO_DEFAULT_TABLES,
+ (void *)(&tables));
+#endif
+
+ 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(pcre_uint8));
+ rc = set_start_bits(code, start_bits, (re->options & PCRE_UTF8) != 0,
+ &compile_block);
+ bits_set = rc == SSB_DONE;
+ if (rc == SSB_UNKNOWN)
+ {
+ *errorptr = "internal error: opcode not recognized";
+ return NULL;
+ }
+ }
+
+/* Find the minimum length of subject string. */
+
+switch(min = find_minlength(re, code, code, re->options, 0))
+ {
+ case -2: *errorptr = "internal error: missing capturing bracket"; return NULL;
+ case -3: *errorptr = "internal error: opcode not recognized"; return NULL;
+ default: break;
+ }
+
+/* If a set of starting bytes has been identified, or if the minimum length is
+greater than zero, or if JIT optimization has been requested, or if
+PCRE_STUDY_EXTRA_NEEDED is set, get a pcre[16]_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. */
+
+if (bits_set || min > 0 || (options & (
+#ifdef SUPPORT_JIT
+ PCRE_STUDY_JIT_COMPILE | PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE |
+ PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE |
+#endif
+ PCRE_STUDY_EXTRA_NEEDED)) != 0)
+ {
+ extra = (PUBL(extra) *)(PUBL(malloc))
+ (sizeof(PUBL(extra)) + sizeof(pcre_study_data));
+ if (extra == NULL)
+ {
+ *errorptr = "failed to get memory";
+ return NULL;
+ }
+
+ study = (pcre_study_data *)((char *)extra + sizeof(PUBL(extra)));
+ extra->flags = PCRE_EXTRA_STUDY_DATA;
+ extra->study_data = study;
+
+ study->size = sizeof(pcre_study_data);
+ study->flags = 0;
+
+ /* Set the start bits always, to avoid unset memory errors if the
+ study data is written to a file, but set the flag only if any of the bits
+ are set, to save time looking when none are. */
+
+ if (bits_set)
+ {
+ study->flags |= PCRE_STUDY_MAPPED;
+ memcpy(study->start_bits, start_bits, sizeof(start_bits));
+ }
+ else memset(study->start_bits, 0, 32 * sizeof(pcre_uint8));
+
+#ifdef PCRE_DEBUG
+ if (bits_set)
+ {
+ pcre_uint8 *ptr = start_bits;
+ int i;
+
+ printf("Start bits:\n");
+ for (i = 0; i < 32; i++)
+ printf("%3d: %02x%s", i * 8, *ptr++, ((i + 1) & 0x7) != 0? " " : "\n");
+ }
+#endif
+
+ /* Always set the minlength value in the block, because the JIT compiler
+ makes use of it. However, don't set the bit unless the length is greater than
+ zero - the interpretive pcre_exec() and pcre_dfa_exec() needn't waste time
+ checking the zero case. */
+
+ if (min > 0)
+ {
+ study->flags |= PCRE_STUDY_MINLEN;
+ study->minlength = min;
+ }
+ else study->minlength = 0;
+
+ /* If JIT support was compiled and requested, attempt the JIT compilation.
+ If no starting bytes were found, and the minimum length is zero, and JIT
+ compilation fails, abandon the extra block and return NULL, unless
+ PCRE_STUDY_EXTRA_NEEDED is set. */
+
+#ifdef SUPPORT_JIT
+ extra->executable_jit = NULL;
+ if ((options & PCRE_STUDY_JIT_COMPILE) != 0)
+ PRIV(jit_compile)(re, extra, JIT_COMPILE);
+ if ((options & PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE) != 0)
+ PRIV(jit_compile)(re, extra, JIT_PARTIAL_SOFT_COMPILE);
+ if ((options & PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE) != 0)
+ PRIV(jit_compile)(re, extra, JIT_PARTIAL_HARD_COMPILE);
+
+ if (study->flags == 0 && (extra->flags & PCRE_EXTRA_EXECUTABLE_JIT) == 0 &&
+ (options & PCRE_STUDY_EXTRA_NEEDED) == 0)
+ {
+#if defined COMPILE_PCRE8
+ pcre_free_study(extra);
+#elif defined COMPILE_PCRE16
+ pcre16_free_study(extra);
+#elif defined COMPILE_PCRE32
+ pcre32_free_study(extra);
+#endif
+ extra = NULL;
+ }
+#endif
+ }
+
+return extra;
+}
+
+
+/*************************************************
+* Free the study data *
+*************************************************/
+
+/* This function frees the memory that was obtained by pcre_study().
+
+Argument: a pointer to the pcre[16]_extra block
+Returns: nothing
+*/
+
+#if defined COMPILE_PCRE8
+PCRE_EXP_DEFN void
+pcre_free_study(pcre_extra *extra)
+#elif defined COMPILE_PCRE16
+PCRE_EXP_DEFN void
+pcre16_free_study(pcre16_extra *extra)
+#elif defined COMPILE_PCRE32
+PCRE_EXP_DEFN void
+pcre32_free_study(pcre32_extra *extra)
+#endif
+{
+if (extra == NULL)
+ return;
+#ifdef SUPPORT_JIT
+if ((extra->flags & PCRE_EXTRA_EXECUTABLE_JIT) != 0 &&
+ extra->executable_jit != NULL)
+ PRIV(jit_free)(extra->executable_jit);
+#endif
+PUBL(free)(extra);
+}
+
+/* End of pcre_study.c */
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