Include pcre sources with library

Advantages are that it works better on non-linux

1 files changed, 1643 insertions, 0 deletions

diff --git a/src/private/pcre_src/pcre_study.c b/src/private/pcre_src/pcre_study.c
new file mode 100644
index 000000000..f19d9fbb9
--- /dev/null
+++ b/src/private/pcre_src/pcre_study.c
@@ -0,0 +1,1643 @@
+/*************************************************
+*      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_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;
+
+      /* 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 pcre_uint32 *p = PRIV(ucd_caseless_sets) + tcode[2];
+        while ((c = *p++) < NOTACHAR)
+          {
+#if defined SUPPORT_UTF && defined COMPILE_PCRE8
+          if (utf)
+            {
+            pcre_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:
+      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 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);
+      try_next = FALSE;
+      break;
+
+      case OP_WHITESPACE:
+      set_type_bits(start_bits, cbit_space, table_limit, cd);
+      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 */