[exim-cvs] cvs commit: exim/exim-src/src/pcre ChangeLog LICE…

トップ ページ
このメッセージを削除
このメッセージに返信
著者: Philip Hazel
日付:  
To: exim-cvs
題目: [exim-cvs] cvs commit: exim/exim-src/src/pcre ChangeLog LICENCE Makefile README config.h dftables.c get.c internal.h maketables.c pcre.c pcre.h pcretest.c printint.c study.c
ph10 2004/10/07 14:04:13 BST

  Added files:
    exim-src/src/pcre    ChangeLog LICENCE Makefile README 
                         config.h dftables.c get.c internal.h 
                         maketables.c pcre.c pcre.h pcretest.c 
                         printint.c study.c 
  Log:
  Start


  Revision  Changes    Path
  1.1       +1611 -0   exim/exim-src/src/pcre/ChangeLog (new)
  1.1       +45 -0     exim/exim-src/src/pcre/LICENCE (new)
  1.1       +51 -0     exim/exim-src/src/pcre/Makefile (new)
  1.1       +20 -0     exim/exim-src/src/pcre/README (new)
  1.1       +39 -0     exim/exim-src/src/pcre/config.h (new)
  1.1       +173 -0    exim/exim-src/src/pcre/dftables.c (new)
  1.1       +357 -0    exim/exim-src/src/pcre/get.c (new)
  1.1       +752 -0    exim/exim-src/src/pcre/internal.h (new)
  1.1       +146 -0    exim/exim-src/src/pcre/maketables.c (new)
  1.1       +9194 -0   exim/exim-src/src/pcre/pcre.c (new)
  1.1       +239 -0    exim/exim-src/src/pcre/pcre.h (new)
  1.1       +1789 -0   exim/exim-src/src/pcre/pcretest.c (new)
  1.1       +465 -0    exim/exim-src/src/pcre/printint.c (new)
  1.1       +484 -0    exim/exim-src/src/pcre/study.c (new)


Index: ChangeLog
====================================================================
ChangeLog for PCRE
------------------

Version 5.0 13-Sep-04
---------------------

   1. Internal change: literal characters are no longer packed up into items
      containing multiple characters in a single byte-string. Each character
      is now matched using a separate opcode. However, there may be more than one
      byte in the character in UTF-8 mode.


   2. The pcre_callout_block structure has two new fields: pattern_position and
      next_item_length. These contain the offset in the pattern to the next match
      item, and its length, respectively.


   3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
      insertion of callouts before each pattern item. Added the /C option to
      pcretest to make use of this.


4. On the advice of a Windows user, the lines

        #if defined(_WIN32) || defined(WIN32)
        _setmode( _fileno( stdout ), 0x8000 );
        #endif  /* defined(_WIN32) || defined(WIN32) */


      have been added to the source of pcretest. This apparently does useful
      magic in relation to line terminators.


   5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
      for the benefit of those environments where the "b" makes a difference.


   6. The icc compiler has the same options as gcc, but "configure" doesn't seem
      to know about it. I have put a hack into configure.in that adds in code
      to set GCC=yes if CC=icc. This seems to end up at a point in the
      generated configure script that is early enough to affect the setting of
      compiler options, which is what is needed, but I have no means of testing
      whether it really works. (The user who reported this had patched the
      generated configure script, which of course I cannot do.)


      LATER: After change 22 below (new libtool files), the configure script
      seems to know about icc (and also ecc). Therefore, I have commented out
      this hack in configure.in.


7. Added support for pkg-config (2 patches were sent in).

   8. Negated POSIX character classes that used a combination of internal tables
      were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
      [[:^ascii]]. Typically, they would match almost any characters. The other
      POSIX classes were not broken in this way.


   9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
      to find the match, as PCRE was deluded into thinking that the match had to
      start at the start point or following a newline. The same bug applied to
      patterns with negative forward assertions or any backward assertions
      preceding ".*" at the start, unless the pattern required a fixed first
      character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.


  10. In UTF-8 mode, when moving forwards in the subject after a failed match
      starting at the last subject character, bytes beyond the end of the subject
      string were read.


  11. Renamed the variable "class" as "classbits" to make life easier for C++
      users. (Previously there was a macro definition, but it apparently wasn't
      enough.)


  12. Added the new field "tables" to the extra data so that tables can be passed
      in at exec time, or the internal tables can be re-selected. This allows
      a compiled regex to be saved and re-used at a later time by a different
      program that might have everything at different addresses.


  13. Modified the pcre-config script so that, when run on Solaris, it shows a
      -R library as well as a -L library.


  14. The debugging options of pcretest (-d on the command line or D on a
      pattern) showed incorrect output for anything following an extended class
      that contained multibyte characters and which was followed by a quantifier.


  15. Added optional support for general category Unicode character properties
      via the \p, \P, and \X escapes. Unicode property support implies UTF-8
      support. It adds about 90K to the size of the library. The meanings of the
      inbuilt class escapes such as \d and \s have NOT been changed.


  16. Updated pcredemo.c to include calls to free() to release the memory for the
      compiled pattern.


  17. The generated file chartables.c was being created in the source directory
      instead of in the building directory. This caused the build to fail if the
      source directory was different from the building directory, and was
      read-only.


  18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
      file. No doubt somebody will tell me if they don't make sense... Also added
      Dan Mooney's comments about building on OpenVMS.


  19. Added support for partial matching via the PCRE_PARTIAL option for
      pcre_exec() and the \P data escape in pcretest.


20. Extended pcretest with 3 new pattern features:

      (i)   A pattern option of the form ">rest-of-line" causes pcretest to
            write the compiled pattern to the file whose name is "rest-of-line".
            This is a straight binary dump of the data, with the saved pointer to
            the character tables forced to be NULL. The study data, if any, is
            written too. After writing, pcretest reads a new pattern.


      (ii)  If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
            compiled pattern from the given file. There must not be any
            occurrences of "<" in the file name (pretty unlikely); if there are,
            pcretest will instead treat the initial "<" as a pattern delimiter.
            After reading in the pattern, pcretest goes on to read data lines as
            usual.


      (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
            and 16-bit fields in a compiled pattern, to simulate a pattern that
            was compiled on a host of opposite endianness.


  21. The pcre-exec() function can now cope with patterns that were compiled on
      hosts of opposite endianness, with this restriction:


        As for any compiled expression that is saved and used later, the tables
        pointer field cannot be preserved; the extra_data field in the arguments
        to pcre_exec() should be used to pass in a tables address if a value
        other than the default internal tables were used at compile time.


  22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
      now diagnosed as an error. Previously, most of the time, a negative number
      would have been treated as zero, but if in addition "ovector" was passed as
      NULL, a crash could occur.


  23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
      new versions from the libtool 1.5 distribution (the last one is a copy of
      a file called libtool.m4). This seems to have fixed the need to patch
      "configure" to support Darwin 1.3 (which I used to do). However, I still
      had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
      workstation).


24. Changed the PCRE licence to be the more standard "BSD" licence.


Version 4.5 01-Dec-03
---------------------

   1. There has been some re-arrangement of the code for the match() function so
      that it can be compiled in a version that does not call itself recursively.
      Instead, it keeps those local variables that need separate instances for
      each "recursion" in a frame on the heap, and gets/frees frames whenever it
      needs to "recurse". Keeping track of where control must go is done by means
      of setjmp/longjmp. The whole thing is implemented by a set of macros that
      hide most of the details from the main code, and operates only if
      NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
      "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
      operating.


      To make it easier for callers to provide specially tailored get/free
      functions for this usage, two new functions, pcre_stack_malloc, and
      pcre_stack_free, are used. They are always called in strict stacking order,
      and the size of block requested is always the same.


      The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
      PCRE has been compiled to use the stack or the heap for recursion. The
      -C option of pcretest uses this to show which version is compiled.


      A new data escape \S, is added to pcretest; it causes the amounts of store
      obtained and freed by both kinds of malloc/free at match time to be added
      to the output.


   2. Changed the locale test to use "fr_FR" instead of "fr" because that's
      what's available on my current Linux desktop machine.


   3. When matching a UTF-8 string, the test for a valid string at the start has
      been extended. If start_offset is not zero, PCRE now checks that it points
      to a byte that is the start of a UTF-8 character. If not, it returns
      PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
      this is necessary because there may be backward assertions in the pattern.
      When matching the same subject several times, it may save resources to use
      PCRE_NO_UTF8_CHECK on all but the first call if the string is long.


   4. The code for checking the validity of UTF-8 strings has been tightened so
      that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
      containing "overlong sequences".


   5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
      I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
      should have been "&", but it just so happened that all the cases this let
      through by mistake were picked up later in the function.


   6. I had used a variable called "isblank" - this is a C99 function, causing
      some compilers to warn. To avoid this, I renamed it (as "blankclass").


   7. Cosmetic: (a) only output another newline at the end of pcretest if it is
      prompting; (b) run "./pcretest /dev/null" at the start of the test script
      so the version is shown; (c) stop "make test" echoing "./RunTest".


8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.

   9. The prototype for memmove() for systems that don't have it was using
      size_t, but the inclusion of the header that defines size_t was later. I've
      moved the #includes for the C headers earlier to avoid this.


  10. Added some adjustments to the code to make it easier to compiler on certain
      special systems:


        (a) Some "const" qualifiers were missing.
        (b) Added the macro EXPORT before all exported functions; by default this
            is defined to be empty.
        (c) Changed the dftables auxiliary program (that builds chartables.c) so
            that it reads its output file name as an argument instead of writing
            to the standard output and assuming this can be redirected.


  11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
      class containing characters with values greater than 255, PCRE compilation
      went into a loop.


  12. A recursive reference to a subpattern that was within another subpattern
      that had a minimum quantifier of zero caused PCRE to crash. For example,
      (x(y(?2))z)? provoked this bug with a subject that got as far as the
      recursion. If the recursively-called subpattern itself had a zero repeat,
      that was OK.


  13. In pcretest, the buffer for reading a data line was set at 30K, but the
      buffer into which it was copied (for escape processing) was still set at
      1024, so long lines caused crashes.


  14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
      "internal error: code overflow...". This applied to any character class
      that was followed by a possessive quantifier.


  15. Modified the Makefile to add libpcre.la as a prerequisite for
      libpcreposix.la because I was told this is needed for a parallel build to
      work.


  16. If a pattern that contained .* following optional items at the start was
      studied, the wrong optimizing data was generated, leading to matching
      errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
      matching string must start with a or b or c. The correct conclusion for
      this pattern is that a match can start with any character.



Version 4.4 13-Aug-03
---------------------

   1. In UTF-8 mode, a character class containing characters with values between
      127 and 255 was not handled correctly if the compiled pattern was studied.
      In fixing this, I have also improved the studying algorithm for such
      classes (slightly).


   2. Three internal functions had redundant arguments passed to them. Removal
      might give a very teeny performance improvement.


   3. Documentation bug: the value of the capture_top field in a callout is *one
      more than* the number of the hightest numbered captured substring.


   4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
      in incorrectly linking with a previously installed version. They now link
      explicitly with libpcre.la.


5. configure.in no longer needs to recognize Cygwin specially.

6. A problem in pcre.in for Windows platforms is fixed.

   7. If a pattern was successfully studied, and the -d (or /D) flag was given to
      pcretest, it used to include the size of the study block as part of its
      output. Unfortunately, the structure contains a field that has a different
      size on different hardware architectures. This meant that the tests that
      showed this size failed. As the block is currently always of a fixed size,
      this information isn't actually particularly useful in pcretest output, so
      I have just removed it.


   8. Three pre-processor statements accidentally did not start in column 1.
      Sadly, there are *still* compilers around that complain, even though
      standard C has not required this for well over a decade. Sigh.


   9. In pcretest, the code for checking callouts passed small integers in the
      callout_data field, which is a void * field. However, some picky compilers
      complained about the casts involved for this on 64-bit systems. Now
      pcretest passes the address of the small integer instead, which should get
      rid of the warnings.


  10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
      both compile and run time, and gives an error if an invalid UTF-8 sequence
      is found. There is a option for disabling this check in cases where the
      string is known to be correct and/or the maximum performance is wanted.


11. In response to a bug report, I changed one line in Makefile.in from

          -Wl,--out-implib,.libs/lib@WIN_PREFIX@??? \
      to
          -Wl,--out-implib,.libs/@WIN_PREFIX@??? \


      to look similar to other lines, but I have no way of telling whether this
      is the right thing to do, as I do not use Windows. No doubt I'll get told
      if it's wrong...



Version 4.3 21-May-03
---------------------

  1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
     Makefile.


2. Some refactoring to improve the quality of the code:

     (i)   The utf8_table... variables are now declared "const".


     (ii)  The code for \cx, which used the "case flipping" table to upper case
           lower case letters, now just substracts 32. This is ASCII-specific,
           but the whole concept of \cx is ASCII-specific, so it seems
           reasonable.


     (iii) PCRE was using its character types table to recognize decimal and
           hexadecimal digits in the pattern. This is silly, because it handles
           only 0-9, a-f, and A-F, but the character types table is locale-
           specific, which means strange things might happen. A private
           table is now used for this - though it costs 256 bytes, a table is
           much faster than multiple explicit tests. Of course, the standard
           character types table is still used for matching digits in subject
           strings against \d.


     (iv)  Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
           ending in _t are). So I've renamed it as ESC_tee.


  3. The first argument for regexec() in the POSIX wrapper should have been
     defined as "const".


  4. Changed pcretest to use malloc() for its buffers so that they can be
     Electric Fenced for debugging.


  5. There were several places in the code where, in UTF-8 mode, PCRE would try
     to read one or more bytes before the start of the subject string. Often this
     had no effect on PCRE's behaviour, but in some circumstances it could
     provoke a segmentation fault.


  6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
     to try to read one or more bytes before the start of the subject string.


  7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
     UTF-8 support could misbehave in various ways if the subject string
     contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
     area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
     back over UTF-8 characters.)



Version 4.2 14-Apr-03
---------------------

1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.

  2. Changes to the building process, supplied by Ronald Landheer-Cieslak
       [ON_WINDOWS]: new variable, "#" on non-Windows platforms
       [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
       [WIN_PREFIX]: new variable, "cyg" for Cygwin
       * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
         and BUILD_EXEEXT
       Note: automatic setting of the BUILD variables is not yet working
       set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
         compile-time but not at link-time
       [LINK]: use for linking executables only
       make different versions for Windows and non-Windows
       [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
         libraries
       [LINK_FOR_BUILD]: new variable
       [OBJEXT]: use throughout
       [EXEEXT]: use throughout
       <winshared>: new target
       <wininstall>: new target
       <dftables.o>: use native compiler
       <dftables>: use native linker
       <install>: handle Windows platform correctly
       <clean>: ditto
       <check>: ditto
       copy DLL to top builddir before testing


     As part of these changes, -no-undefined was removed again. This was reported
     to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
     in any case.


3. Some tidies to get rid of compiler warnings:

     . In the match_data structure, match_limit was an unsigned long int, whereas
       match_call_count was an int. I've made them both unsigned long ints.


     . In pcretest the fact that a const uschar * doesn't automatically cast to
       a void * provoked a warning.


     . Turning on some more compiler warnings threw up some "shadow" variables
       and a few more missing casts.


  4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
     option, a class that contained a single character with a value between 128
     and 255 (e.g. /[\xFF]/) caused PCRE to crash.


  5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
     option, a class that contained several characters, but with at least one
     whose value was between 128 and 255 caused PCRE to crash.



Version 4.1 12-Mar-03
---------------------

1. Compiling with gcc -pedantic found a couple of places where casts were
needed, and a string in dftables.c that was longer than standard compilers are
required to support.

2. Compiling with Sun's compiler found a few more places where the code could
be tidied up in order to avoid warnings.

3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
first of these names is deprecated in the latest Autoconf in favour of the name
CC_FOR_BUILD, because "host" is typically used to mean the system on which the
compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
analogy I have changed it to CFLAGS_FOR_BUILD.

4. Added -no-undefined to the linking command in the Makefile, because this is
apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
linking step for the pcreposix library.

5. PCRE was failing to diagnose the case of two named groups with the same
name.

6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
literal character that is needed in the subject for a match, and scans along to
ensure that it is present before embarking on the full matching process. This
saves time in cases of nested unlimited repeats that are never going to match.
Problem: the scan can take a lot of time if the subject is very long (e.g.
megabytes), thus penalizing straightforward matches. It is now done only if the
amount of subject to be scanned is less than 1000 bytes.

7. A lesser problem with the same optimization is that it was recording the
first character of an anchored pattern as "needed", thus provoking a search
right along the subject, even when the first match of the pattern was going to
fail. The "needed" character is now not set for anchored patterns, unless it
follows something in the pattern that is of non-fixed length. Thus, it still
fulfils its original purpose of finding quick non-matches in cases of nested
unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.


Version 4.0 17-Feb-03
---------------------

1. If a comment in an extended regex that started immediately after a meta-item
extended to the end of string, PCRE compiled incorrect data. This could lead to
all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.

2. Moved to autoconf 2.53 and libtool 1.4.2.

3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
the special perltest8 script is no longer needed - all the tests can be run
from a single perltest script.

4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
by \s. It has now been removed in PCRE. This means it isn't recognized as
whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
class [:space:] *does* include VT, thereby creating a mess.

5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
space and tab.

6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
its new features into the main test script, reducing the number of scripts.

7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
were backward compatible, and made the (?i) apply to the whole pattern, as if
/i were given. Now it behaves more logically, and applies the option setting
only to what follows. PCRE has been changed to follow suit. However, if it
finds options settings right at the start of the pattern, it extracts them into
the global options, as before. Thus, they show up in the info data.

8. Added support for the \Q...\E escape sequence. Characters in between are
treated as literals. This is slightly different from Perl in that $ and @ are
also handled as literals inside the quotes. In Perl, they will cause variable
interpolation. Note the following examples:

      Pattern            PCRE matches      Perl matches


      \Qabc$xyz\E        abc$xyz           abc followed by the contents of $xyz
      \Qabc\$xyz\E       abc\$xyz          abc\$xyz
      \Qabc\E\$\Qxyz\E   abc$xyz           abc$xyz


For compatibility with Perl, \Q...\E sequences are recognized inside character
classes as well as outside them.

9. Re-organized 3 code statements in pcretest to avoid "overflow in
floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
(size_t) cast to one statement in pcretest and one in pcreposix to avoid
signed/unsigned warnings.

10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
option for pcretest, so I've replaced it by a simple function that does just
that job.

11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
"pcregrep -".

12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
Java package. This provides some syntactic sugar for simple cases of what my
documentation calls "once-only subpatterns". A pattern such as x*+ is the same
as (?>x*). In other words, if what is inside (?>...) is just a single repeated
item, you can use this simplified notation. Note that only makes sense with
greedy quantifiers. Consequently, the use of the possessive quantifier forces
greediness, whatever the setting of the PCRE_UNGREEDY option.

13. A change of greediness default within a pattern was not taking effect at
the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
was abstracted outside.

14. PCRE now supports the \G assertion. It is true when the current matching
position is at the start point of the match. This differs from \A when the
starting offset is non-zero. Used with the /g option of pcretest (or similar
code), it works in the same way as it does for Perl's /g option. If all
alternatives of a regex begin with \G, the expression is anchored to the start
match position, and the "anchored" flag is set in the compiled expression.

15. Some bugs concerning the handling of certain option changes within patterns
have been fixed. These applied to options other than (?ims). For example,
"a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
been the other way round. Some of this was related to change 7 above.

16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
POSIX classes only within a class (e.g. /[[:alpha:]]/).

17. Added support for Perl's \C escape. This matches one byte, even in UTF8
mode. Unlike ".", it always matches newline, whatever the setting of
PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
assertions. Perl allows it, but it doesn't (in general) work because it can't
calculate the length of the lookbehind. At least, that's the case for Perl
5.8.0 - I've been told they are going to document that it doesn't work in
future.

18. Added an error diagnosis for escapes that PCRE does not support: these are
\L, \l, \N, \P, \p, \U, \u, and \X.

19. Although correctly diagnosing a missing ']' in a character class, PCRE was
reading past the end of the pattern in cases such as /[abcd/.

20. PCRE was getting more memory than necessary for patterns with classes that
contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.

21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
compiling PCRE for use with Virtual Pascal.

22. Small fix to the Makefile to make it work properly if the build is done
outside the source tree.

23. Added a new extension: a condition to go with recursion. If a conditional
subpattern starts with (?(R) the "true" branch is used if recursion has
happened, whereas the "false" branch is used only at the top level.

24. When there was a very long string of literal characters (over 255 bytes
without UTF support, over 250 bytes with UTF support), the computation of how
much memory was required could be incorrect, leading to segfaults or other
strange effects.

25. PCRE was incorrectly assuming anchoring (either to start of subject or to
start of line for a non-DOTALL pattern) when a pattern started with (.*) and
there was a subsequent back reference to those brackets. This meant that, for
example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
possible to check for precisely this case. All we can do is abandon the
optimization if .* occurs inside capturing brackets when there are any back
references whatsoever. (See below for a better fix that came later.)

26. The handling of the optimization for finding the first character of a
non-anchored pattern, and for finding a character that is required later in the
match were failing in some cases. This didn't break the matching; it just
failed to optimize when it could. The way this is done has been re-implemented.

27. Fixed typo in error message for invalid (?R item (it said "(?p").

28. Added a new feature that provides some of the functionality that Perl
provides with (?{...}). The facility is termed a "callout". The way it is done
in PCRE is for the caller to provide an optional function, by setting
pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
global variable. By default it is unset, which disables all calling out. To get
the function called, the regex must include (?C) at appropriate points. This
is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
This provides a means of identifying different callout points. When PCRE
reaches such a point in the regex, if pcre_callout has been set, the external
function is called. It is provided with data in a structure called
pcre_callout_block, which is defined in pcre.h. If the function returns 0,
matching continues; if it returns a non-zero value, the match at the current
point fails. However, backtracking will occur if possible. [This was changed
later and other features added - see item 49 below.]

29. pcretest is upgraded to test the callout functionality. It provides a
callout function that displays information. By default, it shows the start of
the match and the current position in the text. There are some new data escapes
to vary what happens:

      \C+         in addition, show current contents of captured substrings
      \C-         do not supply a callout function
      \C!n        return 1 when callout number n is reached
      \C!n!m      return 1 when callout number n is reached for the mth time


30. If pcregrep was called with the -l option and just a single file name, it
output "<stdin>" if a match was found, instead of the file name.

31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
pcre_exec(). This saves a malloc/free per call. The default value of
POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
when configuring.

32. The default maximum size of a compiled pattern is 64K. There have been a
few cases of people hitting this limit. The code now uses macros to handle the
storing of links as offsets within the compiled pattern. It defaults to 2-byte
links, but this can be changed to 3 or 4 bytes by --with-link-size when
configuring. Tests 2 and 5 work only with 2-byte links because they output
debugging information about compiled patterns.

33. Internal code re-arrangements:

  (a) Moved the debugging function for printing out a compiled regex into
      its own source file (printint.c) and used #include to pull it into
      pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
      separate copies.


  (b) Defined the list of op-code names for debugging as a macro in
      internal.h so that it is next to the definition of the opcodes.


  (c) Defined a table of op-code lengths for simpler skipping along compiled
      code. This is again a macro in internal.h so that it is next to the
      definition of the opcodes.


34. Added support for recursive calls to individual subpatterns, along the
lines of Robin Houston's patch (but implemented somewhat differently).

35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
allow it to read and process whole directories in Win32. This code was
contributed by Lionel Fourquaux; it has not been tested by me.

36. Added support for named subpatterns. The Python syntax (?P<name>...) is
used to name a group. Names consist of alphanumerics and underscores, and must
be unique. Back references use the syntax (?P=name) and recursive calls use
(?P>name) which is a PCRE extension to the Python extension. Groups still have
numbers. The function pcre_fullinfo() can be used after compilation to extract
a name/number map. There are three relevant calls:

    PCRE_INFO_NAMEENTRYSIZE        yields the size of each entry in the map
    PCRE_INFO_NAMECOUNT            yields the number of entries
    PCRE_INFO_NAMETABLE            yields a pointer to the map.


The map is a vector of fixed-size entries. The size of each entry depends on
the length of the longest name used. The first two bytes of each entry are the
group number, most significant byte first. There follows the corresponding
name, zero terminated. The names are in alphabetical order.

37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
case instead of 255. Making it the same both with and without UTF-8 support
means that the same test output works with both.

38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
calling malloc() with a zero argument.

39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
optimization. I've improved things by keeping a bitmap of backreferences with
numbers 1-31 so that if .* occurs inside capturing brackets that are not in
fact referenced, the optimization can be applied. It is unlikely that a
relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
the match to follow \n) will appear inside brackets with a number greater than
31, but if it does, any back reference > 31 suppresses the optimization.

40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
of disabling numbered capturing parentheses. Any opening parenthesis that is
not followed by ? behaves as if it were followed by ?: but named parentheses
can still be used for capturing (and they will acquire numbers in the usual
way).

41. Redesigned the return codes from the match() function into yes/no/error so
that errors can be passed back from deep inside the nested calls. A malloc
failure while inside a recursive subpattern call now causes the
PCRE_ERROR_NOMEMORY return instead of quietly going wrong.

42. It is now possible to set a limit on the number of times the match()
function is called in a call to pcre_exec(). This facility makes it possible to
limit the amount of recursion and backtracking, though not in a directly
obvious way, because the match() function is used in a number of different
circumstances. The count starts from zero for each position in the subject
string (for non-anchored patterns). The default limit is, for compatibility, a
large number, namely 10 000 000. You can change this in two ways:

  (a) When configuring PCRE before making, you can use --with-match-limit=n
      to set a default value for the compiled library.


  (b) For each call to pcre_exec(), you can pass a pcre_extra block in which
      a different value is set. See 45 below.


If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.

43. Added a new function pcre_config(int, void *) to enable run-time extraction
of things that can be changed at compile time. The first argument specifies
what is wanted and the second points to where the information is to be placed.
The current list of available information is:

    PCRE_CONFIG_UTF8


The output is an integer that is set to one if UTF-8 support is available;
otherwise it is set to zero.

    PCRE_CONFIG_NEWLINE


The output is an integer that it set to the value of the code that is used for
newline. It is either LF (10) or CR (13).

    PCRE_CONFIG_LINK_SIZE


The output is an integer that contains the number of bytes used for internal
linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.

    PCRE_CONFIG_POSIX_MALLOC_THRESHOLD


The output is an integer that contains the threshold above which the POSIX
interface uses malloc() for output vectors. See item 31 above.

    PCRE_CONFIG_MATCH_LIMIT


The output is an unsigned integer that contains the default limit of the number
of match() calls in a pcre_exec() execution. See 42 above.

44. pcretest has been upgraded by the addition of the -C option. This causes it
to extract all the available output from the new pcre_config() function, and to
output it. The program then exits immediately.

45. A need has arisen to pass over additional data with calls to pcre_exec() in
order to support additional features. One way would have been to define
pcre_exec2() (for example) with extra arguments, but this would not have been
extensible, and would also have required all calls to the original function to
be mapped to the new one. Instead, I have chosen to extend the mechanism that
is used for passing in "extra" data from pcre_study().

The pcre_extra structure is now exposed and defined in pcre.h. It currently
contains the following fields:

    flags         a bitmap indicating which of the following fields are set
    study_data    opaque data from pcre_study()
    match_limit   a way of specifying a limit on match() calls for a specific
                    call to pcre_exec()
    callout_data  data for callouts (see 49 below)


The flag bits are also defined in pcre.h, and are

    PCRE_EXTRA_STUDY_DATA
    PCRE_EXTRA_MATCH_LIMIT
    PCRE_EXTRA_CALLOUT_DATA


The pcre_study() function now returns one of these new pcre_extra blocks, with
the actual study data pointed to by the study_data field, and the
PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
before. That is, this change is entirely upwards-compatible and requires no
change to existing code.

If you want to pass in additional data to pcre_exec(), you can either place it
in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
block.

46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
data string contains the escape sequence \M, pcretest calls pcre_exec() several
times with different match limits, until it finds the minimum value needed for
pcre_exec() to complete. The value is then output. This can be instructive; for
most simple matches the number is quite small, but for pathological cases it
gets very large very quickly.

47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
returns the size of the data block pointed to by the study_data field in a
pcre_extra block, that is, the value that was passed as the argument to
pcre_malloc() when PCRE was getting memory in which to place the information
created by pcre_study(). The fourth argument should point to a size_t variable.
pcretest has been extended so that this information is shown after a successful
pcre_study() call when information about the compiled regex is being displayed.

48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
because what follows is always an absolute path. (Later: it turns out that this
is more than cosmetic for MinGW, because it doesn't like empty path
components.)

49. Some changes have been made to the callout feature (see 28 above):

(i) A callout function now has three choices for what it returns:

         0  =>  success, carry on matching
       > 0  =>  failure at this point, but backtrack if possible
       < 0  =>  serious error, return this value from pcre_exec()


       Negative values should normally be chosen from the set of PCRE_ERROR_xxx
       values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
       "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
       use by callout functions. It will never be used by PCRE itself.


  (ii) The pcre_extra structure (see 45 above) has a void * field called
       callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
       pcre_callout_block structure has a field of the same name. The contents of
       the field passed in the pcre_extra structure are passed to the callout
       function in the corresponding field in the callout block. This makes it
       easier to use the same callout-containing regex from multiple threads. For
       testing, the pcretest program has a new data escape


         \C*n        pass the number n (may be negative) as callout_data


       If the callout function in pcretest receives a non-zero value as
       callout_data, it returns that value.


50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
there were some redundant $(CFLAGS) in commands that are now specified as
$(LINK), which already includes $(CFLAGS).

51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
has been compiled with UTF-8 support *and* pcre_compile() has been compiled
with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
one-byte characters throughout. Note that case-insensitive matching applies
only to characters whose values are less than 256. PCRE doesn't support the
notion of cases for higher-valued characters.

  (i)   A character class whose characters are all within 0-255 is handled as
        a bit map, and the map is inverted for negative classes. Previously, a
        character > 255 always failed to match such a class; however it should
        match if the class was a negative one (e.g. [^ab]). This has been fixed.


  (ii)  A negated character class with a single character < 255 is coded as
        "not this character" (OP_NOT). This wasn't working properly when the test
        character was multibyte, either singly or repeated.


  (iii) Repeats of multibyte characters are now handled correctly in UTF-8
        mode, for example: \x{100}{2,3}.


  (iv)  The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
        singly or repeated) now correctly test multibyte characters. However,
        PCRE doesn't recognize any characters with values greater than 255 as
        digits, spaces, or word characters. Such characters always match \D, \S,
        and \W, and never match \d, \s, or \w.


  (v)   Classes may now contain characters and character ranges with values
        greater than 255. For example: [ab\x{100}-\x{400}].


  (vi)  pcregrep now has a --utf-8 option (synonym -u) which makes it call
        PCRE in UTF-8 mode.


52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
retained for backwards compatibility. (Note that LASTLITERAL is also a byte
value.)

53. The single man page has become too large. I have therefore split it up into
a number of separate man pages. These also give rise to individual HTML pages;
these are now put in a separate directory, and there is an index.html page that
lists them all. Some hyperlinking between the pages has been installed.

54. Added convenience functions for handling named capturing parentheses.

55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
are faulted.

56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
calling configure. These values are used when compiling the dftables.c program
which is run to generate the source of the default character tables. They
default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
you will need to set these values.

57. Updated the building process for Windows DLL, as provided by Fred Cox.


Version 3.9 02-Jan-02
---------------------

1. A bit of extraneous text had somehow crept into the pcregrep documentation.

2. If --disable-static was given, the building process failed when trying to
build pcretest and pcregrep. (For some reason it was using libtool to compile
them, which is not right, as they aren't part of the library.)


Version 3.8 18-Dec-01
---------------------

1. The experimental UTF-8 code was completely screwed up. It was packing the
bytes in the wrong order. How dumb can you get?


Version 3.7 29-Oct-01
---------------------

1. In updating pcretest to check change 1 of version 3.6, I screwed up.
This caused pcretest, when used on the test data, to segfault. Unfortunately,
this didn't happen under Solaris 8, where I normally test things.

2. The Makefile had to be changed to make it work on BSD systems, where 'make'
doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
this fix an hour or so after the initial 3.7 release.)


Version 3.6 23-Oct-01
---------------------

1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
offsets passed as NULL with zero offset count.

2. The config.guess and config.sub files had not been updated when I moved to
the latest autoconf.


Version 3.5 15-Aug-01
---------------------

1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
had been forgotten.

2. By using declared but undefined structures, we can avoid using "void"
definitions in pcre.h while keeping the internal definitions of the structures
private.

3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
user point of view, this means that both static and shared libraries are built
by default, but this can be individually controlled. More of the work of
handling this static/shared cases is now inside libtool instead of PCRE's make
file.

4. The pcretest utility is now installed along with pcregrep because it is
useful for users (to test regexs) and by doing this, it automatically gets
relinked by libtool. The documentation has been turned into a man page, so
there are now .1, .txt, and .html versions in /doc.

  5. Upgrades to pcregrep:
     (i)   Added long-form option names like gnu grep.
     (ii)  Added --help to list all options with an explanatory phrase.
     (iii) Added -r, --recursive to recurse into sub-directories.
     (iv)  Added -f, --file to read patterns from a file.


6. pcre_exec() was referring to its "code" argument before testing that
argument for NULL (and giving an error if it was NULL).

7. Upgraded Makefile.in to allow for compiling in a different directory from
the source directory.

8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
options bits, the pointer it was passed was to an int instead of to an unsigned
long int. This mattered only on 64-bit systems.

9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
generated) instead of pcre.in, which it its source. Also made the same change
in several of the .c files.

10. A new release of gcc defines printf() as a macro, which broke pcretest
because it had an ifdef in the middle of a string argument for printf(). Fixed
by using separate calls to printf().

11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
script, to force use of CR or LF instead of \n in the source. On non-Unix
systems, the value can be set in config.h.

12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
absolute limit. Changed the text of the error message to make this clear, and
likewise updated the man page.

13. The limit of 99 on the number of capturing subpatterns has been removed.
The new limit is 65535, which I hope will not be a "real" limit.


Version 3.4 22-Aug-00
---------------------

1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.

2. Diagnose condition (?(0) as an error instead of crashing on matching.


Version 3.3 01-Aug-00
---------------------

1. If an octal character was given, but the value was greater than \377, it
was not getting masked to the least significant bits, as documented. This could
lead to crashes in some systems.

2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.

3. Added the functions pcre_free_substring() and pcre_free_substring_list().
These just pass their arguments on to (pcre_free)(), but they are provided
because some uses of PCRE bind it to non-C systems that can call its functions,
but cannot call free() or pcre_free() directly.

4. Add "make test" as a synonym for "make check". Corrected some comments in
the Makefile.

5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
Makefile.

6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
command called pgrep for grepping around the active processes.

7. Added the beginnings of support for UTF-8 character strings.

8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
RANLIB to ./ltconfig so that they are used by libtool. I think these are all
the relevant ones. (AR is not passed because ./ltconfig does its own figuring
out for the ar command.)


Version 3.2 12-May-00
---------------------

This is purely a bug fixing release.

1. If the pattern /((Z)+|A)*/ was matched agained ZABCDEFG it matched Z instead
of ZA. This was just one example of several cases that could provoke this bug,
which was introduced by change 9 of version 2.00. The code for breaking
infinite loops after an iteration that matches an empty string was't working
correctly.

2. The pcretest program was not imitating Perl correctly for the pattern /a*/g
when matched against abbab (for example). After matching an empty string, it
wasn't forcing anchoring when setting PCRE_NOTEMPTY for the next attempt; this
caused it to match further down the string than it should.

3. The code contained an inclusion of sys/types.h. It isn't clear why this
was there because it doesn't seem to be needed, and it causes trouble on some
systems, as it is not a Standard C header. It has been removed.

4. Made 4 silly changes to the source to avoid stupid compiler warnings that
were reported on the Macintosh. The changes were from

    while ((c = *(++ptr)) != 0 && c != '\n');
  to
    while ((c = *(++ptr)) != 0 && c != '\n') ;


Totally extraordinary, but if that's what it takes...

5. PCRE is being used in one environment where neither memmove() nor bcopy() is
available. Added HAVE_BCOPY and an autoconf test for it; if neither
HAVE_MEMMOVE nor HAVE_BCOPY is set, use a built-in emulation function which
assumes the way PCRE uses memmove() (always moving upwards).

6. PCRE is being used in one environment where strchr() is not available. There
was only one use in pcre.c, and writing it out to avoid strchr() probably gives
faster code anyway.


Version 3.1 09-Feb-00
---------------------

The only change in this release is the fixing of some bugs in Makefile.in for
the "install" target:

(1) It was failing to install pcreposix.h.

(2) It was overwriting the pcre.3 man page with the pcreposix.3 man page.


Version 3.0 01-Feb-00
---------------------

1. Add support for the /+ modifier to perltest (to output $` like it does in
pcretest).

2. Add support for the /g modifier to perltest.

3. Fix pcretest so that it behaves even more like Perl for /g when the pattern
matches null strings.

4. Fix perltest so that it doesn't do unwanted things when fed an empty
pattern. Perl treats empty patterns specially - it reuses the most recent
pattern, which is not what we want. Replace // by /(?#)/ in order to avoid this
effect.

5. The POSIX interface was broken in that it was just handing over the POSIX
captured string vector to pcre_exec(), but (since release 2.00) PCRE has
required a bigger vector, with some working space on the end. This means that
the POSIX wrapper now has to get and free some memory, and copy the results.

6. Added some simple autoconf support, placing the test data and the
documentation in separate directories, re-organizing some of the
information files, and making it build pcre-config (a GNU standard). Also added
libtool support for building PCRE as a shared library, which is now the
default.

7. Got rid of the leading zero in the definition of PCRE_MINOR because 08 and
09 are not valid octal constants. Single digits will be used for minor values
less than 10.

8. Defined REG_EXTENDED and REG_NOSUB as zero in the POSIX header, so that
existing programs that set these in the POSIX interface can use PCRE without
modification.

9. Added a new function, pcre_fullinfo() with an extensible interface. It can
return all that pcre_info() returns, plus additional data. The pcre_info()
function is retained for compatibility, but is considered to be obsolete.

10. Added experimental recursion feature (?R) to handle one common case that
Perl 5.6 will be able to do with (?p{...}).

11. Added support for POSIX character classes like [:alpha:], which Perl is
adopting.


Version 2.08 31-Aug-99
----------------------

1. When startoffset was not zero and the pattern began with ".*", PCRE was not
trying to match at the startoffset position, but instead was moving forward to
the next newline as if a previous match had failed.

2. pcretest was not making use of PCRE_NOTEMPTY when repeating for /g and /G,
and could get into a loop if a null string was matched other than at the start
of the subject.

3. Added definitions of PCRE_MAJOR and PCRE_MINOR to pcre.h so the version can
be distinguished at compile time, and for completeness also added PCRE_DATE.

5. Added Paul Sokolovsky's minor changes to make it easy to compile a Win32 DLL
in GnuWin32 environments.


Version 2.07 29-Jul-99
----------------------

1. The documentation is now supplied in plain text form and HTML as well as in
the form of man page sources.

2. C++ compilers don't like assigning (void *) values to other pointer types.
In particular this affects malloc(). Although there is no problem in Standard
C, I've put in casts to keep C++ compilers happy.

3. Typo on pcretest.c; a cast of (unsigned char *) in the POSIX regexec() call
should be (const char *).

4. If NOPOSIX is defined, pcretest.c compiles without POSIX support. This may
be useful for non-Unix systems who don't want to bother with the POSIX stuff.
However, I haven't made this a standard facility. The documentation doesn't
mention it, and the Makefile doesn't support it.

5. The Makefile now contains an "install" target, with editable destinations at
the top of the file. The pcretest program is not installed.

6. pgrep -V now gives the PCRE version number and date.

7. Fixed bug: a zero repetition after a literal string (e.g. /abcde{0}/) was
causing the entire string to be ignored, instead of just the last character.

8. If a pattern like /"([^\\"]+|\\.)*"/ is applied in the normal way to a
non-matching string, it can take a very, very long time, even for strings of
quite modest length, because of the nested recursion. PCRE now does better in
some of these cases. It does this by remembering the last required literal
character in the pattern, and pre-searching the subject to ensure it is present
before running the real match. In other words, it applies a heuristic to detect
some types of certain failure quickly, and in the above example, if presented
with a string that has no trailing " it gives "no match" very quickly.

9. A new runtime option PCRE_NOTEMPTY causes null string matches to be ignored;
other alternatives are tried instead.


Version 2.06 09-Jun-99
----------------------

1. Change pcretest's output for amount of store used to show just the code
space, because the remainder (the data block) varies in size between 32-bit and
64-bit systems.

2. Added an extra argument to pcre_exec() to supply an offset in the subject to
start matching at. This allows lookbehinds to work when searching for multiple
occurrences in a string.

3. Added additional options to pcretest for testing multiple occurrences:

     /+   outputs the rest of the string that follows a match
     /g   loops for multiple occurrences, using the new startoffset argument
     /G   loops for multiple occurrences by passing an incremented pointer


4. PCRE wasn't doing the "first character" optimization for patterns starting
with \b or \B, though it was doing it for other lookbehind assertions. That is,
it wasn't noticing that a match for a pattern such as /\bxyz/ has to start with
the letter 'x'. On long subject strings, this gives a significant speed-up.


Version 2.05 21-Apr-99
----------------------

1. Changed the type of magic_number from int to long int so that it works
properly on 16-bit systems.

2. Fixed a bug which caused patterns starting with .* not to work correctly
when the subject string contained newline characters. PCRE was assuming
anchoring for such patterns in all cases, which is not correct because .* will
not pass a newline unless PCRE_DOTALL is set. It now assumes anchoring only if
DOTALL is set at top level; otherwise it knows that patterns starting with .*
must be retried after every newline in the subject.


Version 2.04 18-Feb-99
----------------------

1. For parenthesized subpatterns with repeats whose minimum was zero, the
computation of the store needed to hold the pattern was incorrect (too large).
If such patterns were nested a few deep, this could multiply and become a real
problem.

2. Added /M option to pcretest to show the memory requirement of a specific
pattern. Made -m a synonym of -s (which does this globally) for compatibility.

3. Subpatterns of the form (regex){n,m} (i.e. limited maximum) were being
compiled in such a way that the backtracking after subsequent failure was
pessimal. Something like (a){0,3} was compiled as (a)?(a)?(a)? instead of
((a)((a)(a)?)?)? with disastrous performance if the maximum was of any size.


Version 2.03 02-Feb-99
----------------------

1. Fixed typo and small mistake in man page.

2. Added 4th condition (GPL supersedes if conflict) and created separate
LICENCE file containing the conditions.

3. Updated pcretest so that patterns such as /abc\/def/ work like they do in
Perl, that is the internal \ allows the delimiter to be included in the
pattern. Locked out the use of \ as a delimiter. If \ immediately follows
the final delimiter, add \ to the end of the pattern (to test the error).

4. Added the convenience functions for extracting substrings after a successful
match. Updated pcretest to make it able to test these functions.


Version 2.02 14-Jan-99
----------------------

1. Initialized the working variables associated with each extraction so that
their saving and restoring doesn't refer to uninitialized store.

2. Put dummy code into study.c 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.

3. Pcretest: the timing code wasn't using LOOPREPEAT for timing execution
calls, and wasn't printing the correct value for compiling calls. Increased the
default value of LOOPREPEAT, and the number of significant figures in the
times.

4. Changed "/bin/rm" in the Makefile to "-rm" so it works on Windows NT.

5. Renamed "deftables" as "dftables" to get it down to 8 characters, to avoid
a building problem on Windows NT with a FAT file system.


Version 2.01 21-Oct-98
----------------------

1. Changed the API for pcre_compile() to allow for the provision of a pointer
to character tables built by pcre_maketables() in the current locale. If NULL
is passed, the default tables are used.


Version 2.00 24-Sep-98
----------------------

1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
it any more.

2. Allow quantification of (?>) groups, and make it work correctly.

3. The first character computation wasn't working for (?>) groups.

4. Correct the implementation of \Z (it is permitted to match on the \n at the
end of the subject) and add 5.005's \z, which really does match only at the
very end of the subject.

5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.

6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
localized options. All options to pcre_study() were also removed.

7. Add other new features from 5.005:

     $(?<=           positive lookbehind
     $(?<!           negative lookbehind
     (?imsx-imsx)    added the unsetting capability
                     such a setting is global if at outer level; local otherwise
     (?imsx-imsx:)   non-capturing groups with option setting
     (?(cond)re|re)  conditional pattern matching


     A backreference to itself in a repeated group matches the previous
     captured string.


8. General tidying up of studying (both automatic and via "study")
consequential on the addition of new assertions.

9. As in 5.005, unlimited repeated groups that could match an empty substring
are no longer faulted at compile time. Instead, the loop is forcibly broken at
runtime if any iteration does actually match an empty substring.

10. Include the RunTest script in the distribution.

11. Added tests from the Perl 5.005_02 distribution. This showed up a few
discrepancies, some of which were old and were also with respect to 5.004. They
have now been fixed.


Version 1.09 28-Apr-98
----------------------

1. A negated single character class followed by a quantifier with a minimum
value of one (e.g. [^x]{1,6} ) was not compiled correctly. This could lead to
program crashes, or just wrong answers. This did not apply to negated classes
containing more than one character, or to minima other than one.


Version 1.08 27-Mar-98
----------------------

1. Add PCRE_UNGREEDY to invert the greediness of quantifiers.

2. Add (?U) and (?X) to set PCRE_UNGREEDY and PCRE_EXTRA respectively. The
latter must appear before anything that relies on it in the pattern.


Version 1.07 16-Feb-98
----------------------

1. A pattern such as /((a)*)*/ was not being diagnosed as in error (unlimited
repeat of a potentially empty string).


Version 1.06 23-Jan-98
----------------------

1. Added Markus Oberhumer's little patches for C++.

2. Literal strings longer than 255 characters were broken.


Version 1.05 23-Dec-97
----------------------

1. Negated character classes containing more than one character were failing if
PCRE_CASELESS was set at run time.


Version 1.04 19-Dec-97
----------------------

1. Corrected the man page, where some "const" qualifiers had been omitted.

2. Made debugging output print "{0,xxx}" instead of just "{,xxx}" to agree with
input syntax.

3. Fixed memory leak which occurred when a regex with back references was
matched with an offsets vector that wasn't big enough. The temporary memory
that is used in this case wasn't being freed if the match failed.

4. Tidied pcretest to ensure it frees memory that it gets.

5. Temporary memory was being obtained in the case where the passed offsets
vector was exactly big enough.

6. Corrected definition of offsetof() from change 5 below.

7. I had screwed up change 6 below and broken the rules for the use of
setjmp(). Now fixed.


Version 1.03 18-Dec-97
----------------------

1. A erroneous regex with a missing opening parenthesis was correctly
diagnosed, but PCRE attempted to access brastack[-1], which could cause crashes
on some systems.

2. Replaced offsetof(real_pcre, code) by offsetof(real_pcre, code[0]) because
it was reported that one broken compiler failed on the former because "code" is
also an independent variable.

3. The erroneous regex a[]b caused an array overrun reference.

4. A regex ending with a one-character negative class (e.g. /[^k]$/) did not
fail on data ending with that character. (It was going on too far, and checking
the next character, typically a binary zero.) This was specific to the
optimized code for single-character negative classes.

5. Added a contributed patch from the TIN world which does the following:

    + Add an undef for memmove, in case the the system defines a macro for it.


    + Add a definition of offsetof(), in case there isn't one. (I don't know
      the reason behind this - offsetof() is part of the ANSI standard - but
      it does no harm).


    + Reduce the ifdef's in pcre.c using macro DPRINTF, thereby eliminating
      most of the places where whitespace preceded '#'. I have given up and
      allowed the remaining 2 cases to be at the margin.


    + Rename some variables in pcre to eliminate shadowing. This seems very
      pedantic, but does no harm, of course.


6. Moved the call to setjmp() into its own function, to get rid of warnings
from gcc -Wall, and avoided calling it at all unless PCRE_EXTRA is used.

7. Constructs such as \d{8,} were compiling into the equivalent of
\d{8}\d{0,65527} instead of \d{8}\d* which didn't make much difference to the
outcome, but in this particular case used more store than had been allocated,
which caused the bug to be discovered because it threw up an internal error.

8. The debugging code in both pcre and pcretest for outputting the compiled
form of a regex was going wrong in the case of back references followed by
curly-bracketed repeats.


Version 1.02 12-Dec-97
----------------------

1. Typos in pcre.3 and comments in the source fixed.

2. Applied a contributed patch to get rid of places where it used to remove
'const' from variables, and fixed some signed/unsigned and uninitialized
variable warnings.

3. Added the "runtest" target to Makefile.

4. Set default compiler flag to -O2 rather than just -O.


Version 1.01 19-Nov-97
----------------------

1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
like /([ab]*)*/, that is, for classes with more than one character in them.

2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
as /((?>a*))*/ (a PCRE_EXTRA facility).


Version 1.00 18-Nov-97
----------------------

1. Added compile-time macros to support systems such as SunOS4 which don't have
memmove() or strerror() but have other things that can be used instead.

2. Arranged that "make clean" removes the executables.


Version 0.99 27-Oct-97
----------------------

1. Fixed bug in code for optimizing classes with only one character. It was
initializing a 32-byte map regardless, which could cause it to run off the end
of the memory it had got.

2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.


Version 0.98 22-Oct-97
----------------------

1. Fixed bug in code for handling temporary memory usage when there are more
back references than supplied space in the ovector. This could cause segfaults.


Version 0.97 21-Oct-97
----------------------

1. Added the \X "cut" facility, conditional on PCRE_EXTRA.

2. Optimized negated single characters not to use a bit map.

3. Brought error texts together as macro definitions; clarified some of them;
fixed one that was wrong - it said "range out of order" when it meant "invalid
escape sequence".

4. Changed some char * arguments to const char *.

5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).

6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
pcretest.


Version 0.96 16-Oct-97
----------------------

1. Added a simple "pgrep" utility to the distribution.

2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
where "ddd" means "one or more decimal digits".

3. Fixed serious bug. If a pattern had a back reference, but the call to
pcre_exec() didn't supply a large enough ovector to record the related
identifying subpattern, the match always failed. PCRE now remembers the number
of the largest back reference, and gets some temporary memory in which to save
the offsets during matching if necessary, in order to ensure that
backreferences always work.

4. Increased the compatibility with Perl in a number of ways:

    (a) . no longer matches \n by default; an option PCRE_DOTALL is provided
        to request this handling. The option can be set at compile or exec time.


    (b) $ matches before a terminating newline by default; an option
        PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
        mode). The option can be set at compile or exec time.


    (c) The handling of \ followed by a digit other than 0 is now supposed to be
        the same as Perl's. If the decimal number it represents is less than 10
        or there aren't that many previous left capturing parentheses, an octal
        escape is read. Inside a character class, it's always an octal escape,
        even if it is a single digit.


    (d) An escaped but undefined alphabetic character is taken as a literal,
        unless PCRE_EXTRA is set. Currently this just reserves the remaining
        escapes.


    (e) {0} is now permitted. (The previous item is removed from the compiled
        pattern).


5. Changed all the names of code files so that the basic parts are no longer
than 10 characters, and abolished the teeny "globals.c" file.

6. Changed the handling of character classes; they are now done with a 32-byte
bit map always.

7. Added the -d and /D options to pcretest to make it possible to look at the
internals of compilation without having to recompile pcre.


Version 0.95 23-Sep-97
----------------------

1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
\x20 at the start of a run of normal characters. These were being treated as
real characters, instead of the source characters being re-checked.


Version 0.94 18-Sep-97
----------------------

1. The functions are now thread-safe, with the caveat that the global variables
containing pointers to malloc() and free() or alternative functions are the
same for all threads.

2. Get pcre_study() to generate a bitmap of initial characters for non-
anchored patterns when this is possible, and use it if passed to pcre_exec().


Version 0.93 15-Sep-97
----------------------

1. /(b)|(:+)/ was computing an incorrect first character.

2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
but not actually doing anything yet.

3. Treat "-" characters in classes that cannot be part of ranges as literals,
as Perl does (e.g. [-az] or [az-]).

4. Set the anchored flag if a branch starts with .* or .*? because that tests
all possible positions.

5. Split up into different modules to avoid including unneeded functions in a
compiled binary. However, compile and exec are still in one module. The "study"
function is split off.

6. The character tables are now in a separate module whose source is generated
by an auxiliary program - but can then be edited by hand if required. There are
now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
toupper() in the code.

7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
make them global. Abolish the function for setting them, as the caller can now
set them directly.


Version 0.92 11-Sep-97
----------------------

1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
(e.g. /a{1,3}/) was broken (I mis-optimized it).

2. Caseless matching was not working in character classes if the characters in
the pattern were in upper case.

3. Make ranges like [W-c] work in the same way as Perl for caseless matching.

4. Make PCRE_ANCHORED public and accept as a compile option.

5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
pass them.

6. Give an error if bad option bits passed at compile or run time.

7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
pcretest to cause it to pass that flag.

8. Add pcre_info(), to get the number of identifying subpatterns, the stored
options, and the first character, if set.

9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.


Version 0.91 10-Sep-97
----------------------

1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
match the empty string as in /(a*)*/. It was looping and ultimately crashing.

2. PCRE was looping on encountering an indefinitely repeated back reference to
a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
Perl does - treats the match as successful.

****

Index: LICENCE
====================================================================
PCRE LICENCE
------------

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.

Release 5 of PCRE is distributed under the terms of the "BSD" licence, as
specified below. The documentation for PCRE, supplied in the "doc"
directory, is distributed under the same terms as the software itself.

Written by: Philip Hazel <ph10@???>

University of Cambridge Computing Service,
Cambridge, England. Phone: +44 1223 334714.

Copyright (c) 1997-2004 University of Cambridge
All rights reserved.

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.

End

Index: Makefile
====================================================================
# $Cambridge: exim/exim-src/src/pcre/Makefile,v 1.1 2004/10/07 13:04:13 ph10 Exp $

# Makefile for PCRE (Perl-Compatible Regular Expression) library for use by
# Exim. This is a tailored Makefile, not the normal one that comes with the
# PCRE distribution.

# These variables are in practice overridden from the Exim Makefile.

AR = ar cq
CC = gcc -O2 -Wall
CFLAGS =
RANLIB = @true

##############################################################################

OBJ = maketables.o get.o pcre.o study.o

  all:            libpcre.a ../pcretest


  ../pcretest: libpcre.a pcretest.o
          $(CC) $(CFLAGS) -o ../pcretest pcretest.o libpcre.a


  libpcre.a:      $(OBJ)
          -rm -f libpcre.a
          $(AR) libpcre.a $(OBJ)
          $(RANLIB) libpcre.a


  pcre.o:         chartables.c pcre.c config.h pcre.h internal.h Makefile
          $(CC) -c $(CFLAGS) pcre.c


  maketables.o:   maketables.c config.h pcre.h internal.h Makefile
          $(CC) -c $(CFLAGS) maketables.c


  get.o:          get.c pcre.h config.h internal.h Makefile
          $(CC) -c $(CFLAGS) get.c


  study.o:        study.c pcre.h config.h internal.h Makefile
          $(CC) -c $(CFLAGS) study.c


  pcretest.o:     pcretest.c config.h pcre.h internal.h Makefile
          $(CC) -c -DNOPOSIX $(CFLAGS) -I. pcretest.c


# An auxiliary program makes the default character table source

  chartables.c:   dftables
          ./dftables chartables.c


  dftables:       dftables.c maketables.c config.h pcre.h internal.h Makefile
          $(CC) -o dftables $(CFLAGS) dftables.c


# End

Index: README
====================================================================
$Cambridge: exim/exim-src/src/pcre/README,v 1.1 2004/10/07 13:04:13 ph10 Exp $

PCRE for use in Exim
--------------------

This directory contains a subset of the files from the PCRE distribution,
enough to supply regular expression support for Exim, plus the pcretest test
program. Do not start from here if you want to install PCRE as a free-standing
library for use by other programs. Get the full PCRE distribution, which can be
obtained from

ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-x.x.tar.gz

where x.x is the version number. This contains support for a POSIX interface to
PCRE, a "grep" program that uses PCRE, and the means to build PCRE as a shared
library. It is configured by autoconf, and has "make install" support in the
conventional way.

Philip Hazel <ph10@???>
February 2000

Index: config.h
====================================================================
/* $Cambridge: exim/exim-src/src/pcre/config.h,v 1.1 2004/10/07 13:04:13 ph10 Exp $ */

  /*************************************************
  *           config.h for PCRE for Exim           *
  *************************************************/


/* The PCRE sources include config.h, which for a free-standing PCRE build gets
set up by autoconf. For the embedded version in Exim, this file, which is
manually maintained, is used.

The only configuration thing that matters for the PCRE library itself is
whether the memmove() function exists or not. It should be present in all
Standard C libraries, but is missing in SunOS4. PCRE expects autoconf to set
HAVE_MEMMOVE to 1 in config.h when memmove() is present. If that is not set, it
defines memmove() as a macro for bcopy().

Exim works differently. It handles this case by defining memmove() as a macro
in its os.h-SunOS4 file. We interface this to PCRE by including the os.h file
here, and then defining HAVE_MEMOVE so that PCRE's code in internal.h leaves
things alone. */

#include "../os.h"
#define HAVE_MEMMOVE 1

/* We also set up directly a number of parameters that, in the freestanding
PCRE, can be adjusted by "configure". */

  #define NEWLINE                 '\n'
  #define LINK_SIZE               2
  #define MATCH_LIMIT             10000000
  #define POSIX_MALLOC_THRESHOLD  10


/* There is some stuff in the PCRE sources for compilation on non-Unix systems
and non-ASCII systems. For Exim's purposes, just flatten it all. */

#define EBCDIC 0
#define EXPORT

/* End */

  Index: dftables.c
  ====================================================================
  /*************************************************
  *      Perl-Compatible Regular Expressions       *
  *************************************************/


/*
PCRE is a library of functions to support regular expressions whose syntax
and semantics are as close as possible to those of the Perl 5 language.

Written by: Philip Hazel <ph10@???>

             Copyright (c) 1997-2004 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 is a support program to generate the file chartables.c, containing
character tables of various kinds. They are built according to the default C
locale and used as the default tables by PCRE. Now that pcre_maketables is
a function visible to the outside world, we make use of its code from here in
order to be consistent. */

#include <ctype.h>
#include <stdio.h>
#include <string.h>

#include "internal.h"

  #define DFTABLES          /* maketables.c notices this */
  #include "maketables.c"



int main(int argc, char **argv)
{
int i;
FILE *f;
const unsigned char *tables = pcre_maketables();

  if (argc != 2)
    {
    fprintf(stderr, "dftables: one filename argument is required\n");
    return 1;
    }


  f = fopen(argv[1], "w");
  if (f == NULL)
    {
    fprintf(stderr, "dftables: failed to open %s for writing\n", argv[1]);
    return 1;
    }


/* There are two fprintf() calls here, because gcc in pedantic mode complains
about the very long string otherwise. */

  fprintf(f,
    "/*************************************************\n"
    "*      Perl-Compatible Regular Expressions       *\n"
    "*************************************************/\n\n"
    "/* This file is automatically written by the dftables auxiliary \n"
    "program. If you edit it by hand, you might like to edit the Makefile to \n"
    "prevent its ever being regenerated.\n\n");
  fprintf(f,
    "This file is #included in the compilation of pcre.c to build the default\n"
    "character tables which are used when no tables are passed to the compile\n"
    "function. */\n\n"
    "static unsigned char pcre_default_tables[] = {\n\n"
    "/* This table is a lower casing table. */\n\n");


  fprintf(f, "  ");
  for (i = 0; i < 256; i++)
    {
    if ((i & 7) == 0 && i != 0) fprintf(f, "\n  ");
    fprintf(f, "%3d", *tables++);
    if (i != 255) fprintf(f, ",");
    }
  fprintf(f, ",\n\n");


fprintf(f, "/* This table is a case flipping table. */\n\n");

  fprintf(f, "  ");
  for (i = 0; i < 256; i++)
    {
    if ((i & 7) == 0 && i != 0) fprintf(f, "\n  ");
    fprintf(f, "%3d", *tables++);
    if (i != 255) fprintf(f, ",");
    }
  fprintf(f, ",\n\n");


  fprintf(f,
    "/* This table contains bit maps for various character classes.\n"
    "Each map is 32 bytes long and the bits run from the least\n"
    "significant end of each byte. The classes that have their own\n"
    "maps are: space, xdigit, digit, upper, lower, word, graph\n"
    "print, punct, and cntrl. Other classes are built from combinations. */\n\n");


  fprintf(f, "  ");
  for (i = 0; i < cbit_length; i++)
    {
    if ((i & 7) == 0 && i != 0)
      {
      if ((i & 31) == 0) fprintf(f, "\n");
      fprintf(f, "\n  ");
      }
    fprintf(f, "0x%02x", *tables++);
    if (i != cbit_length - 1) fprintf(f, ",");
    }
  fprintf(f, ",\n\n");


  fprintf(f,
    "/* This table identifies various classes of character by individual bits:\n"
    "  0x%02x   white space character\n"
    "  0x%02x   letter\n"
    "  0x%02x   decimal digit\n"
    "  0x%02x   hexadecimal digit\n"
    "  0x%02x   alphanumeric or '_'\n"
    "  0x%02x   regular expression metacharacter or binary zero\n*/\n\n",
    ctype_space, ctype_letter, ctype_digit, ctype_xdigit, ctype_word,
    ctype_meta);


  fprintf(f, "  ");
  for (i = 0; i < 256; i++)
    {
    if ((i & 7) == 0 && i != 0)
      {
      fprintf(f, " /* ");
      if (isprint(i-8)) fprintf(f, " %c -", i-8);
        else fprintf(f, "%3d-", i-8);
      if (isprint(i-1)) fprintf(f, " %c ", i-1);
        else fprintf(f, "%3d", i-1);
      fprintf(f, " */\n  ");
      }
    fprintf(f, "0x%02x", *tables++);
    if (i != 255) fprintf(f, ",");
    }


  fprintf(f, "};/* ");
  if (isprint(i-8)) fprintf(f, " %c -", i-8);
    else fprintf(f, "%3d-", i-8);
  if (isprint(i-1)) fprintf(f, " %c ", i-1);
    else fprintf(f, "%3d", i-1);
  fprintf(f, " */\n\n/* End of chartables.c */\n");


fclose(f);
return 0;
}

/* End of dftables.c */

  Index: get.c
  ====================================================================
  /*************************************************
  *      Perl-Compatible Regular Expressions       *
  *************************************************/


/*
This 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. See
the file Tech.Notes for some information on the internals.

Written by: Philip Hazel <ph10@???>

             Copyright (c) 1997-2003 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 some convenience functions for extracting substrings
from the subject string after a regex match has succeeded. The original idea
for these functions came from Scott Wimer. */


/* Include the internals header, which itself includes Standard C headers plus
the external pcre header. */

#include "internal.h"


  /*************************************************
  *           Find number for named string         *
  *************************************************/


/* This function is used by the two extraction functions below, as well
as being generally available.

  Arguments:
    code        the compiled regex
    stringname  the name whose number is required


  Returns:      the number of the named parentheses, or a negative number
                  (PCRE_ERROR_NOSUBSTRING) if not found
  */


int
pcre_get_stringnumber(const pcre *code, const char *stringname)
{
int rc;
int entrysize;
int top, bot;
uschar *nametable;

  if ((rc = pcre_fullinfo(code, NULL, PCRE_INFO_NAMECOUNT, &top)) != 0)
    return rc;
  if (top <= 0) return PCRE_ERROR_NOSUBSTRING;


  if ((rc = pcre_fullinfo(code, NULL, PCRE_INFO_NAMEENTRYSIZE, &entrysize)) != 0)
    return rc;
  if ((rc = pcre_fullinfo(code, NULL, PCRE_INFO_NAMETABLE, &nametable)) != 0)
    return rc;


  bot = 0;
  while (top > bot)
    {
    int mid = (top + bot) / 2;
    uschar *entry = nametable + entrysize*mid;
    int c = strcmp(stringname, (char *)(entry + 2));
    if (c == 0) return (entry[0] << 8) + entry[1];
    if (c > 0) bot = mid + 1; else top = mid;
    }


return PCRE_ERROR_NOSUBSTRING;
}



  /*************************************************
  *      Copy captured string to given buffer      *
  *************************************************/


/* This function copies a single captured substring into a given buffer.
Note that we use memcpy() rather than strncpy() in case there are binary zeros
in the string.

  Arguments:
    subject        the subject string that was matched
    ovector        pointer to the offsets table
    stringcount    the number of substrings that were captured
                     (i.e. the yield of the pcre_exec call, unless
                     that was zero, in which case it should be 1/3
                     of the offset table size)
    stringnumber   the number of the required substring
    buffer         where to put the substring
    size           the size of the buffer


  Returns:         if successful:
                     the length of the copied string, not including the zero
                     that is put on the end; can be zero
                   if not successful:
                     PCRE_ERROR_NOMEMORY (-6) buffer too small
                     PCRE_ERROR_NOSUBSTRING (-7) no such captured substring
  */


  int
  pcre_copy_substring(const char *subject, int *ovector, int stringcount,
    int stringnumber, char *buffer, int size)
  {
  int yield;
  if (stringnumber < 0 || stringnumber >= stringcount)
    return PCRE_ERROR_NOSUBSTRING;
  stringnumber *= 2;
  yield = ovector[stringnumber+1] - ovector[stringnumber];
  if (size < yield + 1) return PCRE_ERROR_NOMEMORY;
  memcpy(buffer, subject + ovector[stringnumber], yield);
  buffer[yield] = 0;
  return yield;
  }




/*************************************************
* Copy named captured string to given buffer *
*************************************************/

/* This function copies a single captured substring into a given buffer,
identifying it by name.

  Arguments:
    code           the compiled regex
    subject        the subject string that was matched
    ovector        pointer to the offsets table
    stringcount    the number of substrings that were captured
                     (i.e. the yield of the pcre_exec call, unless
                     that was zero, in which case it should be 1/3
                     of the offset table size)
    stringname     the name of the required substring
    buffer         where to put the substring
    size           the size of the buffer


  Returns:         if successful:
                     the length of the copied string, not including the zero
                     that is put on the end; can be zero
                   if not successful:
                     PCRE_ERROR_NOMEMORY (-6) buffer too small
                     PCRE_ERROR_NOSUBSTRING (-7) no such captured substring
  */


  int
  pcre_copy_named_substring(const pcre *code, const char *subject, int *ovector,
    int stringcount, const char *stringname, char *buffer, int size)
  {
  int n = pcre_get_stringnumber(code, stringname);
  if (n <= 0) return n;
  return pcre_copy_substring(subject, ovector, stringcount, n, buffer, size);
  }




  /*************************************************
  *      Copy all captured strings to new store    *
  *************************************************/


/* This function gets one chunk of store and builds a list of pointers and all
of the captured substrings in it. A NULL pointer is put on the end of the list.

  Arguments:
    subject        the subject string that was matched
    ovector        pointer to the offsets table
    stringcount    the number of substrings that were captured
                     (i.e. the yield of the pcre_exec call, unless
                     that was zero, in which case it should be 1/3
                     of the offset table size)
    listptr        set to point to the list of pointers


  Returns:         if successful: 0
                   if not successful:
                     PCRE_ERROR_NOMEMORY (-6) failed to get store
  */


  int
  pcre_get_substring_list(const char *subject, int *ovector, int stringcount,
    const char ***listptr)
  {
  int i;
  int size = sizeof(char *);
  int double_count = stringcount * 2;
  char **stringlist;
  char *p;


  for (i = 0; i < double_count; i += 2)
    size += sizeof(char *) + ovector[i+1] - ovector[i] + 1;


stringlist = (char **)(pcre_malloc)(size);
if (stringlist == NULL) return PCRE_ERROR_NOMEMORY;

*listptr = (const char **)stringlist;
p = (char *)(stringlist + stringcount + 1);

  for (i = 0; i < double_count; i += 2)
    {
    int len = ovector[i+1] - ovector[i];
    memcpy(p, subject + ovector[i], len);
    *stringlist++ = p;
    p += len;
    *p++ = 0;
    }


*stringlist = NULL;
return 0;
}



  /*************************************************
  *   Free store obtained by get_substring_list    *
  *************************************************/


/* This function exists for the benefit of people calling PCRE from non-C
programs that can call its functions, but not free() or (pcre_free)() directly.

  Argument:   the result of a previous pcre_get_substring_list()
  Returns:    nothing
  */


void
pcre_free_substring_list(const char **pointer)
{
(pcre_free)((void *)pointer);
}



  /*************************************************
  *      Copy captured string to new store         *
  *************************************************/


/* This function copies a single captured substring into a piece of new
store

  Arguments:
    subject        the subject string that was matched
    ovector        pointer to the offsets table
    stringcount    the number of substrings that were captured
                     (i.e. the yield of the pcre_exec call, unless
                     that was zero, in which case it should be 1/3
                     of the offset table size)
    stringnumber   the number of the required substring
    stringptr      where to put a pointer to the substring


  Returns:         if successful:
                     the length of the string, not including the zero that
                     is put on the end; can be zero
                   if not successful:
                     PCRE_ERROR_NOMEMORY (-6) failed to get store
                     PCRE_ERROR_NOSUBSTRING (-7) substring not present
  */


  int
  pcre_get_substring(const char *subject, int *ovector, int stringcount,
    int stringnumber, const char **stringptr)
  {
  int yield;
  char *substring;
  if (stringnumber < 0 || stringnumber >= stringcount)
    return PCRE_ERROR_NOSUBSTRING;
  stringnumber *= 2;
  yield = ovector[stringnumber+1] - ovector[stringnumber];
  substring = (char *)(pcre_malloc)(yield + 1);
  if (substring == NULL) return PCRE_ERROR_NOMEMORY;
  memcpy(substring, subject + ovector[stringnumber], yield);
  substring[yield] = 0;
  *stringptr = substring;
  return yield;
  }




  /*************************************************
  *   Copy named captured string to new store      *
  *************************************************/


/* This function copies a single captured substring, identified by name, into
new store.

  Arguments:
    code           the compiled regex
    subject        the subject string that was matched
    ovector        pointer to the offsets table
    stringcount    the number of substrings that were captured
                     (i.e. the yield of the pcre_exec call, unless
                     that was zero, in which case it should be 1/3
                     of the offset table size)
    stringname     the name of the required substring
    stringptr      where to put the pointer


  Returns:         if successful:
                     the length of the copied string, not including the zero
                     that is put on the end; can be zero
                   if not successful:
                     PCRE_ERROR_NOMEMORY (-6) couldn't get memory
                     PCRE_ERROR_NOSUBSTRING (-7) no such captured substring
  */


  int
  pcre_get_named_substring(const pcre *code, const char *subject, int *ovector,
    int stringcount, const char *stringname, const char **stringptr)
  {
  int n = pcre_get_stringnumber(code, stringname);
  if (n <= 0) return n;
  return pcre_get_substring(subject, ovector, stringcount, n, stringptr);
  }





  /*************************************************
  *       Free store obtained by get_substring     *
  *************************************************/


/* This function exists for the benefit of people calling PCRE from non-C
programs that can call its functions, but not free() or (pcre_free)() directly.

  Argument:   the result of a previous pcre_get_substring()
  Returns:    nothing
  */


void
pcre_free_substring(const char *pointer)
{
(pcre_free)((void *)pointer);
}

/* End of get.c */

  Index: internal.h
  ====================================================================
  /*************************************************
  *      Perl-Compatible Regular Expressions       *
  *************************************************/



/* This 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. See
the file doc/Tech.Notes for some information on the internals.

Written by: Philip Hazel <ph10@???>

             Copyright (c) 1997-2004 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 header contains definitions that are shared between the different
modules, but which are not relevant to the outside. */

/* Get the definitions provided by running "configure" */

#include "config.h"

/* Standard C headers plus the external interface definition. The only time
setjmp and stdarg are used is when NO_RECURSE is set. */

#include <ctype.h>
#include <limits.h>
#include <setjmp.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

  #ifndef PCRE_SPY
  #define PCRE_DEFINITION       /* Win32 __declspec(export) trigger for .dll */
  #endif


/* We need to have types that specify unsigned 16-bit and 32-bit integers. We
cannot determine these outside the compilation (e.g. by running a program as
part of "configure") because PCRE is often cross-compiled for use on other
systems. Instead we make use of the maximum sizes that are available at
preprocessor time in standard C environments. */

  #if USHRT_MAX == 65535
    typedef unsigned short pcre_uint16;
  #elif UINT_MAX == 65535
    typedef unsigned int pcre_uint16;
  #else
    #error Cannot determine a type for 16-bit unsigned integers
  #endif


  #if UINT_MAX == 4294967295
    typedef unsigned int pcre_uint32;
  #elif ULONG_MAX == 4294967295
    typedef unsigned long int pcre_uint32;
  #else
    #error Cannot determine a type for 32-bit unsigned integers
  #endif


/* All character handling must be done as unsigned characters. Otherwise there
are problems with top-bit-set characters and functions such as isspace().
However, we leave the interface to the outside world as char *, because that
should make things easier for callers. We define a short type for unsigned char
to save lots of typing. I tried "uchar", but it causes problems on Digital
Unix, where it is defined in sys/types, so use "uschar" instead. */

typedef unsigned char uschar;

/* Include the public PCRE header */

#include "pcre.h"

/* When compiling for use with the Virtual Pascal compiler, these functions
need to have their names changed. PCRE must be compiled with the -DVPCOMPAT
option on the command line. */

  #ifdef VPCOMPAT
  #define strncmp(s1,s2,m) _strncmp(s1,s2,m)
  #define memcpy(d,s,n)    _memcpy(d,s,n)
  #define memmove(d,s,n)   _memmove(d,s,n)
  #define memset(s,c,n)    _memset(s,c,n)
  #else  /* VPCOMPAT */


/* To cope with SunOS4 and other systems that lack memmove() but have bcopy(),
define a macro for memmove() if HAVE_MEMMOVE is false, provided that HAVE_BCOPY
is set. Otherwise, include an emulating function for those systems that have
neither (there some non-Unix environments where this is the case). This assumes
that all calls to memmove are moving strings upwards in store, which is the
case in PCRE. */

  #if ! HAVE_MEMMOVE
  #undef  memmove        /* some systems may have a macro */
  #if HAVE_BCOPY
  #define memmove(a, b, c) bcopy(b, a, c)
  #else  /* HAVE_BCOPY */
  void *
  pcre_memmove(unsigned char *dest, const unsigned char *src, size_t n)
  {
  int i;
  dest += n;
  src += n;
  for (i = 0; i < n; ++i) *(--dest) =  *(--src);
  }
  #define memmove(a, b, c) pcre_memmove(a, b, c)
  #endif   /* not HAVE_BCOPY */
  #endif   /* not HAVE_MEMMOVE */
  #endif   /* not VPCOMPAT */



/* PCRE keeps offsets in its compiled code as 2-byte quantities (always stored
in big-endian order) by default. These are used, for example, to link from the
start of a subpattern to its alternatives and its end. The use of 2 bytes per
offset limits the size of the compiled regex to around 64K, which is big enough
for almost everybody. However, I received a request for an even bigger limit.
For this reason, and also to make the code easier to maintain, the storing and
loading of offsets from the byte string is now handled by the macros that are
defined here.

The macros are controlled by the value of LINK_SIZE. This defaults to 2 in
the config.h file, but can be overridden by using -D on the command line. This
is automated on Unix systems via the "configure" command. */

#if LINK_SIZE == 2

  #define PUT(a,n,d)   \
    (a[n] = (d) >> 8), \
    (a[(n)+1] = (d) & 255)


  #define GET(a,n) \
    (((a)[n] << 8) | (a)[(n)+1])


#define MAX_PATTERN_SIZE (1 << 16)


#elif LINK_SIZE == 3

  #define PUT(a,n,d)       \
    (a[n] = (d) >> 16),    \
    (a[(n)+1] = (d) >> 8), \
    (a[(n)+2] = (d) & 255)


  #define GET(a,n) \
    (((a)[n] << 16) | ((a)[(n)+1] << 8) | (a)[(n)+2])


#define MAX_PATTERN_SIZE (1 << 24)


#elif LINK_SIZE == 4

  #define PUT(a,n,d)        \
    (a[n] = (d) >> 24),     \
    (a[(n)+1] = (d) >> 16), \
    (a[(n)+2] = (d) >> 8),  \
    (a[(n)+3] = (d) & 255)


  #define GET(a,n) \
    (((a)[n] << 24) | ((a)[(n)+1] << 16) | ((a)[(n)+2] << 8) | (a)[(n)+3])


#define MAX_PATTERN_SIZE (1 << 30) /* Keep it positive */


#else
#error LINK_SIZE must be either 2, 3, or 4
#endif


/* Convenience macro defined in terms of the others */

#define PUTINC(a,n,d) PUT(a,n,d), a += LINK_SIZE


/* PCRE uses some other 2-byte quantities that do not change when the size of
offsets changes. There are used for repeat counts and for other things such as
capturing parenthesis numbers in back references. */

  #define PUT2(a,n,d)   \
    a[n] = (d) >> 8; \
    a[(n)+1] = (d) & 255


  #define GET2(a,n) \
    (((a)[n] << 8) | (a)[(n)+1])


#define PUT2INC(a,n,d) PUT2(a,n,d), a += 2


/* In case there is no definition of offsetof() provided - though any proper
Standard C system should have one. */

#ifndef offsetof
#define offsetof(p_type,field) ((size_t)&(((p_type *)0)->field))
#endif


/* These are the public options that can change during matching. */

#define PCRE_IMS (PCRE_CASELESS|PCRE_MULTILINE|PCRE_DOTALL)

/* Private options flags start at the most significant end of the four bytes,
but skip the top bit so we can use ints for convenience without getting tangled
with negative values. The public options defined in pcre.h start at the least
significant end. Make sure they don't overlap, though now that we have expanded
to four bytes, there is plenty of space. */

  #define PCRE_FIRSTSET      0x40000000  /* first_byte is set */
  #define PCRE_REQCHSET      0x20000000  /* req_byte is set */
  #define PCRE_STARTLINE     0x10000000  /* start after \n for multiline */
  #define PCRE_ICHANGED      0x08000000  /* i option changes within regex */
  #define PCRE_NOPARTIAL     0x04000000  /* can't use partial with this regex */


/* Options for the "extra" block produced by pcre_study(). */

  #define PCRE_STUDY_MAPPED   0x01     /* a map of starting chars exists */


/* Masks for identifying the public options which are permitted at compile
time, run time or study time, respectively. */

  #define PUBLIC_OPTIONS \
    (PCRE_CASELESS|PCRE_EXTENDED|PCRE_ANCHORED|PCRE_MULTILINE| \
     PCRE_DOTALL|PCRE_DOLLAR_ENDONLY|PCRE_EXTRA|PCRE_UNGREEDY|PCRE_UTF8| \
     PCRE_NO_AUTO_CAPTURE|PCRE_NO_UTF8_CHECK|PCRE_AUTO_CALLOUT)


  #define PUBLIC_EXEC_OPTIONS \
    (PCRE_ANCHORED|PCRE_NOTBOL|PCRE_NOTEOL|PCRE_NOTEMPTY|PCRE_NO_UTF8_CHECK| \
     PCRE_PARTIAL)


#define PUBLIC_STUDY_OPTIONS 0 /* None defined */

/* Magic number to provide a small check against being handed junk. */

#define MAGIC_NUMBER 0x50435245UL /* 'PCRE' */

/* Negative values for the firstchar and reqchar variables */

#define REQ_UNSET (-2)
#define REQ_NONE (-1)

/* Flags added to firstbyte or reqbyte; a "non-literal" item is either a
variable-length repeat, or a anything other than literal characters. */

  #define REQ_CASELESS 0x0100    /* indicates caselessness */
  #define REQ_VARY     0x0200    /* reqbyte followed non-literal item */


/* Miscellaneous definitions */

typedef int BOOL;

  #define FALSE   0
  #define TRUE    1


/* Escape items that are just an encoding of a particular data value. Note that
ESC_n is defined as yet another macro, which is set in config.h to either \n
(the default) or \r (which some people want). */

#ifndef ESC_e
#define ESC_e 27
#endif

#ifndef ESC_f
#define ESC_f '\f'
#endif

#ifndef ESC_n
#define ESC_n NEWLINE
#endif

#ifndef ESC_r
#define ESC_r '\r'
#endif

/* We can't officially use ESC_t because it is a POSIX reserved identifier
(presumably because of all the others like size_t). */

#ifndef ESC_tee
#define ESC_tee '\t'
#endif

/* These are escaped items that aren't just an encoding of a particular data
value such as \n. They must have non-zero values, as check_escape() returns
their negation. Also, they must appear in the same order as in the opcode
definitions below, up to ESC_z. There's a dummy for OP_ANY because it
corresponds to "." rather than an escape sequence. The final one must be
ESC_REF as subsequent values are used for \1, \2, \3, etc. There is are two
tests in the code for an escape greater than ESC_b and less than ESC_Z to
detect the types that may be repeated. These are the types that consume
characters. If any new escapes are put in between that don't consume a
character, that code will have to change. */

  enum { ESC_A = 1, ESC_G, ESC_B, ESC_b, ESC_D, ESC_d, ESC_S, ESC_s, ESC_W,
         ESC_w, ESC_dum1, ESC_C, ESC_P, ESC_p, ESC_X, ESC_Z, ESC_z, ESC_E,
         ESC_Q, ESC_REF };


/* Flag bits and data types for the extended class (OP_XCLASS) for classes that
contain UTF-8 characters with values greater than 255. */

  #define XCL_NOT    0x01    /* Flag: this is a negative class */
  #define XCL_MAP    0x02    /* Flag: a 32-byte map is present */


  #define XCL_END       0    /* Marks end of individual items */
  #define XCL_SINGLE    1    /* Single item (one multibyte char) follows */
  #define XCL_RANGE     2    /* A range (two multibyte chars) follows */
  #define XCL_PROP      3    /* Unicode property (one property code) follows */
  #define XCL_NOTPROP   4    /* Unicode inverted property (ditto) */



/* Opcode table: OP_BRA must be last, as all values >= it are used for brackets
that extract substrings. Starting from 1 (i.e. after OP_END), the values up to
OP_EOD must correspond in order to the list of escapes immediately above.
Note that whenever this list is updated, the two macro definitions that follow
must also be updated to match. */

  enum {
    OP_END,            /* 0 End of pattern */


    /* Values corresponding to backslashed metacharacters */


    OP_SOD,            /* 1 Start of data: \A */
    OP_SOM,            /* 2 Start of match (subject + offset): \G */
    OP_NOT_WORD_BOUNDARY,  /*  3 \B */
    OP_WORD_BOUNDARY,      /*  4 \b */
    OP_NOT_DIGIT,          /*  5 \D */
    OP_DIGIT,              /*  6 \d */
    OP_NOT_WHITESPACE,     /*  7 \S */
    OP_WHITESPACE,         /*  8 \s */
    OP_NOT_WORDCHAR,       /*  9 \W */
    OP_WORDCHAR,           /* 10 \w */
    OP_ANY,            /* 11 Match any character */
    OP_ANYBYTE,        /* 12 Match any byte (\C); different to OP_ANY for UTF-8 */
    OP_NOTPROP,        /* 13 \P (not Unicode property) */
    OP_PROP,           /* 14 \p (Unicode property) */
    OP_EXTUNI,         /* 15 \X (extended Unicode sequence */
    OP_EODN,           /* 16 End of data or \n at end of data: \Z. */
    OP_EOD,            /* 17 End of data: \z */


    OP_OPT,            /* 18 Set runtime options */
    OP_CIRC,           /* 19 Start of line - varies with multiline switch */
    OP_DOLL,           /* 20 End of line - varies with multiline switch */
    OP_CHAR,           /* 21 Match one character, casefully */
    OP_CHARNC,         /* 22 Match one character, caselessly */
    OP_NOT,            /* 23 Match anything but the following char */


    OP_STAR,           /* 24 The maximizing and minimizing versions of */
    OP_MINSTAR,        /* 25 all these opcodes must come in pairs, with */
    OP_PLUS,           /* 26 the minimizing one second. */
    OP_MINPLUS,        /* 27 This first set applies to single characters */
    OP_QUERY,          /* 28 */
    OP_MINQUERY,       /* 29 */
    OP_UPTO,           /* 30 From 0 to n matches */
    OP_MINUPTO,        /* 31 */
    OP_EXACT,          /* 32 Exactly n matches */


    OP_NOTSTAR,        /* 33 The maximizing and minimizing versions of */
    OP_NOTMINSTAR,     /* 34 all these opcodes must come in pairs, with */
    OP_NOTPLUS,        /* 35 the minimizing one second. */
    OP_NOTMINPLUS,     /* 36 This set applies to "not" single characters */
    OP_NOTQUERY,       /* 37 */
    OP_NOTMINQUERY,    /* 38 */
    OP_NOTUPTO,        /* 39 From 0 to n matches */
    OP_NOTMINUPTO,     /* 40 */
    OP_NOTEXACT,       /* 41 Exactly n matches */


    OP_TYPESTAR,       /* 42 The maximizing and minimizing versions of */
    OP_TYPEMINSTAR,    /* 43 all these opcodes must come in pairs, with */
    OP_TYPEPLUS,       /* 44 the minimizing one second. These codes must */
    OP_TYPEMINPLUS,    /* 45 be in exactly the same order as those above. */
    OP_TYPEQUERY,      /* 46 This set applies to character types such as \d */
    OP_TYPEMINQUERY,   /* 47 */
    OP_TYPEUPTO,       /* 48 From 0 to n matches */
    OP_TYPEMINUPTO,    /* 49 */
    OP_TYPEEXACT,      /* 50 Exactly n matches */


    OP_CRSTAR,         /* 51 The maximizing and minimizing versions of */
    OP_CRMINSTAR,      /* 52 all these opcodes must come in pairs, with */
    OP_CRPLUS,         /* 53 the minimizing one second. These codes must */
    OP_CRMINPLUS,      /* 54 be in exactly the same order as those above. */
    OP_CRQUERY,        /* 55 These are for character classes and back refs */
    OP_CRMINQUERY,     /* 56 */
    OP_CRRANGE,        /* 57 These are different to the three sets above. */
    OP_CRMINRANGE,     /* 58 */


    OP_CLASS,          /* 59 Match a character class, chars < 256 only */
    OP_NCLASS,         /* 60 Same, but the bitmap was created from a negative
                             class - the difference is relevant only when a UTF-8
                             character > 255 is encountered. */


    OP_XCLASS,         /* 61 Extended class for handling UTF-8 chars within the
                             class. This does both positive and negative. */


    OP_REF,            /* 62 Match a back reference */
    OP_RECURSE,        /* 63 Match a numbered subpattern (possibly recursive) */
    OP_CALLOUT,        /* 64 Call out to external function if provided */


    OP_ALT,            /* 65 Start of alternation */
    OP_KET,            /* 66 End of group that doesn't have an unbounded repeat */
    OP_KETRMAX,        /* 67 These two must remain together and in this */
    OP_KETRMIN,        /* 68 order. They are for groups the repeat for ever. */


    /* The assertions must come before ONCE and COND */


    OP_ASSERT,         /* 69 Positive lookahead */
    OP_ASSERT_NOT,     /* 70 Negative lookahead */
    OP_ASSERTBACK,     /* 71 Positive lookbehind */
    OP_ASSERTBACK_NOT, /* 72 Negative lookbehind */
    OP_REVERSE,        /* 73 Move pointer back - used in lookbehind assertions */


    /* ONCE and COND must come after the assertions, with ONCE first, as there's
    a test for >= ONCE for a subpattern that isn't an assertion. */


    OP_ONCE,           /* 74 Once matched, don't back up into the subpattern */
    OP_COND,           /* 75 Conditional group */
    OP_CREF,           /* 76 Used to hold an extraction string number (cond ref) */


    OP_BRAZERO,        /* 77 These two must remain together and in this */
    OP_BRAMINZERO,     /* 78 order. */


    OP_BRANUMBER,      /* 79 Used for extracting brackets whose number is greater
                             than can fit into an opcode. */


    OP_BRA             /* 80 This and greater values are used for brackets that
                             extract substrings up to EXTRACT_BASIC_MAX. After
                             that, use is made of OP_BRANUMBER. */
  };


/* WARNING WARNING WARNING: There is an implicit assumption in pcre.c and
study.c that all opcodes are less than 128 in value. This makes handling UTF-8
character sequences easier. */

/* The highest extraction number before we have to start using additional
bytes. (Originally PCRE didn't have support for extraction counts highter than
this number.) The value is limited by the number of opcodes left after OP_BRA,
i.e. 255 - OP_BRA. We actually set it a bit lower to leave room for additional
opcodes. */

#define EXTRACT_BASIC_MAX 100


/* This macro defines textual names for all the opcodes. There are used only
for debugging, in pcre.c when DEBUG is defined, and also in pcretest.c. The
macro is referenced only in printint.c. */

  #define OP_NAME_LIST \
    "End", "\\A", "\\G", "\\B", "\\b", "\\D", "\\d",                \
    "\\S", "\\s", "\\W", "\\w", "Any", "Anybyte",                   \
    "notprop", "prop", "extuni",                                    \
    "\\Z", "\\z",                                                   \
    "Opt", "^", "$", "char", "charnc", "not",                       \
    "*", "*?", "+", "+?", "?", "??", "{", "{", "{",                 \
    "*", "*?", "+", "+?", "?", "??", "{", "{", "{",                 \
    "*", "*?", "+", "+?", "?", "??", "{", "{", "{",                 \
    "*", "*?", "+", "+?", "?", "??", "{", "{",                      \
    "class", "nclass", "xclass", "Ref", "Recurse", "Callout",       \
    "Alt", "Ket", "KetRmax", "KetRmin", "Assert", "Assert not",     \
    "AssertB", "AssertB not", "Reverse", "Once", "Cond", "Cond ref",\
    "Brazero", "Braminzero", "Branumber", "Bra"



/* This macro defines the length of fixed length operations in the compiled
regex. The lengths are used when searching for specific things, and also in the
debugging printing of a compiled regex. We use a macro so that it can be
incorporated both into pcre.c and pcretest.c without being publicly exposed.

As things have been extended, some of these are no longer fixed lenths, but are
minima instead. For example, the length of a single-character repeat may vary
in UTF-8 mode. The code that uses this table must know about such things. */

  #define OP_LENGTHS \
    1,                             /* End                                    */ \
    1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  /* \A, \G, \B, \B, \D, \d, \S, \s, \W, \w */ \
    1, 1,                          /* Any, Anybyte                           */ \
    2, 2, 1,                       /* NOTPROP, PROP, EXTUNI                  */ \
    1, 1, 2, 1, 1,                 /* \Z, \z, Opt, ^, $                      */ \
    2,                             /* Char  - the minimum length             */ \
    2,                             /* Charnc  - the minimum length           */ \
    2,                             /* not                                    */ \
    /* Positive single-char repeats                            ** These are  */ \
    2, 2, 2, 2, 2, 2,              /* *, *?, +, +?, ?, ??      ** minima in  */ \
    4, 4, 4,                       /* upto, minupto, exact     ** UTF-8 mode */ \
    /* Negative single-char repeats - only for chars < 256                   */ \
    2, 2, 2, 2, 2, 2,              /* NOT *, *?, +, +?, ?, ??                */ \
    4, 4, 4,                       /* NOT upto, minupto, exact               */ \
    /* Positive type repeats                                                 */ \
    2, 2, 2, 2, 2, 2,              /* Type *, *?, +, +?, ?, ??               */ \
    4, 4, 4,                       /* Type upto, minupto, exact              */ \
    /* Character class & ref repeats                                         */ \
    1, 1, 1, 1, 1, 1,              /* *, *?, +, +?, ?, ??                    */ \
    5, 5,                          /* CRRANGE, CRMINRANGE                    */ \
   33,                             /* CLASS                                  */ \
   33,                             /* NCLASS                                 */ \
    0,                             /* XCLASS - variable length               */ \
    3,                             /* REF                                    */ \
    1+LINK_SIZE,                   /* RECURSE                                */ \
    2+2*LINK_SIZE,                 /* CALLOUT                                */ \
    1+LINK_SIZE,                   /* Alt                                    */ \
    1+LINK_SIZE,                   /* Ket                                    */ \
    1+LINK_SIZE,                   /* KetRmax                                */ \
    1+LINK_SIZE,                   /* KetRmin                                */ \
    1+LINK_SIZE,                   /* Assert                                 */ \
    1+LINK_SIZE,                   /* Assert not                             */ \
    1+LINK_SIZE,                   /* Assert behind                          */ \
    1+LINK_SIZE,                   /* Assert behind not                      */ \
    1+LINK_SIZE,                   /* Reverse                                */ \
    1+LINK_SIZE,                   /* Once                                   */ \
    1+LINK_SIZE,                   /* COND                                   */ \
    3,                             /* CREF                                   */ \
    1, 1,                          /* BRAZERO, BRAMINZERO                    */ \
    3,                             /* BRANUMBER                              */ \
    1+LINK_SIZE                    /* BRA                                    */ \



/* A magic value for OP_CREF to indicate the "in recursion" condition. */

#define CREF_RECURSE 0xffff

/* The texts of compile-time error messages are defined as macros here so that
they can be accessed by the POSIX wrapper and converted into error codes. Yes,
I could have used error codes in the first place, but didn't feel like changing
just to accommodate the POSIX wrapper. */

#define ERR1 "\\ at end of pattern"
#define ERR2 "\\c at end of pattern"
#define ERR3 "unrecognized character follows \\"
#define ERR4 "numbers out of order in {} quantifier"
#define ERR5 "number too big in {} quantifier"
#define ERR6 "missing terminating ] for character class"
#define ERR7 "invalid escape sequence in character class"
#define ERR8 "range out of order in character class"
#define ERR9 "nothing to repeat"
#define ERR10 "operand of unlimited repeat could match the empty string"
#define ERR11 "internal error: unexpected repeat"
#define ERR12 "unrecognized character after (?"
#define ERR13 "POSIX named classes are supported only within a class"
#define ERR14 "missing )"
#define ERR15 "reference to non-existent subpattern"
#define ERR16 "erroffset passed as NULL"
#define ERR17 "unknown option bit(s) set"
#define ERR18 "missing ) after comment"
#define ERR19 "parentheses nested too deeply"
#define ERR20 "regular expression too large"
#define ERR21 "failed to get memory"
#define ERR22 "unmatched parentheses"
#define ERR23 "internal error: code overflow"
#define ERR24 "unrecognized character after (?<"
#define ERR25 "lookbehind assertion is not fixed length"
#define ERR26 "malformed number after (?("
#define ERR27 "conditional group contains more than two branches"
#define ERR28 "assertion expected after (?("
#define ERR29 "(?R or (?digits must be followed by )"
#define ERR30 "unknown POSIX class name"
#define ERR31 "POSIX collating elements are not supported"
#define ERR32 "this version of PCRE is not compiled with PCRE_UTF8 support"
#define ERR33 "spare error"
#define ERR34 "character value in \\x{...} sequence is too large"
#define ERR35 "invalid condition (?(0)"
#define ERR36 "\\C not allowed in lookbehind assertion"
#define ERR37 "PCRE does not support \\L, \\l, \\N, \\U, or \\u"
#define ERR38 "number after (?C is > 255"
#define ERR39 "closing ) for (?C expected"
#define ERR40 "recursive call could loop indefinitely"
#define ERR41 "unrecognized character after (?P"
#define ERR42 "syntax error after (?P"
#define ERR43 "two named groups have the same name"
#define ERR44 "invalid UTF-8 string"
#define ERR45 "support for \\P, \\p, and \\X has not been compiled"
#define ERR46 "malformed \\P or \\p sequence"
#define ERR47 "unknown property name after \\P or \\p"

/* The real format of the start of the pcre block; the index of names and the
code vector run on as long as necessary after the end. We store an explicit
offset to the name table so that if a regex is compiled on one host, saved, and
then run on another where the size of pointers is different, all might still
be well. For the case of compiled-on-4 and run-on-8, we include an extra
pointer that is always NULL. For future-proofing, we also include a few dummy
fields - even though you can never get this planning right!

NOTE NOTE NOTE:
Because people can now save and re-use compiled patterns, any additions to this
structure should be made at the end, and something earlier (e.g. a new
flag in the options or one of the dummy fields) should indicate that the new
fields are present. Currently PCRE always sets the dummy fields to zero.
NOTE NOTE NOTE:
*/

  typedef struct real_pcre {
    pcre_uint32 magic_number;
    pcre_uint32 size;               /* Total that was malloced */
    pcre_uint32 options;
    pcre_uint32 dummy1;             /* For future use, maybe */


    pcre_uint16 top_bracket;
    pcre_uint16 top_backref;
    pcre_uint16 first_byte;
    pcre_uint16 req_byte;
    pcre_uint16 name_table_offset;  /* Offset to name table that follows */
    pcre_uint16 name_entry_size;    /* Size of any name items */
    pcre_uint16 name_count;         /* Number of name items */
    pcre_uint16 dummy2;             /* For future use, maybe */


    const unsigned char *tables;    /* Pointer to tables or NULL for std */
    const unsigned char *nullpad;   /* NULL padding */
  } real_pcre;


/* The format of the block used to store data from pcre_study(). The same
remark (see NOTE above) about extending this structure applies. */

  typedef struct pcre_study_data {
    pcre_uint32 size;               /* Total that was malloced */
    pcre_uint32 options;
    uschar start_bits[32];
  } pcre_study_data;


/* Structure for passing "static" information around between the functions
doing the compiling, so that they are thread-safe. */

  typedef struct compile_data {
    const uschar *lcc;            /* Points to lower casing table */
    const uschar *fcc;            /* Points to case-flipping table */
    const uschar *cbits;          /* Points to character type table */
    const uschar *ctypes;         /* Points to table of type maps */
    const uschar *start_code;     /* The start of the compiled code */
    const uschar *start_pattern;  /* The start of the pattern */
    uschar *name_table;           /* The name/number table */
    int  names_found;             /* Number of entries so far */
    int  name_entry_size;         /* Size of each entry */
    int  top_backref;             /* Maximum back reference */
    unsigned int backref_map;     /* Bitmap of low back refs */
    int  req_varyopt;             /* "After variable item" flag for reqbyte */
    BOOL nopartial;               /* Set TRUE if partial won't work */
  } compile_data;


/* Structure for maintaining a chain of pointers to the currently incomplete
branches, for testing for left recursion. */

  typedef struct branch_chain {
    struct branch_chain *outer;
    uschar *current;
  } branch_chain;


/* Structure for items in a linked list that represents an explicit recursive
call within the pattern. */

  typedef struct recursion_info {
    struct recursion_info *prevrec; /* Previous recursion record (or NULL) */
    int group_num;                /* Number of group that was called */
    const uschar *after_call;     /* "Return value": points after the call in the expr */
    const uschar *save_start;     /* Old value of md->start_match */
    int *offset_save;             /* Pointer to start of saved offsets */
    int saved_max;                /* Number of saved offsets */
  } recursion_info;


/* When compiling in a mode that doesn't use recursive calls to match(),
a structure is used to remember local variables on the heap. It is defined in
pcre.c, close to the match() function, so that it is easy to keep it in step
with any changes of local variable. However, the pointer to the current frame
must be saved in some "static" place over a longjmp(). We declare the
structure here so that we can put a pointer in the match_data structure.
NOTE: This isn't used for a "normal" compilation of pcre. */

struct heapframe;

/* Structure for passing "static" information around between the functions
doing the matching, so that they are thread-safe. */

  typedef struct match_data {
    unsigned long int match_call_count; /* As it says */
    unsigned long int match_limit;/* As it says */
    int   *offset_vector;         /* Offset vector */
    int    offset_end;            /* One past the end */
    int    offset_max;            /* The maximum usable for return data */
    const uschar *lcc;            /* Points to lower casing table */
    const uschar *ctypes;         /* Points to table of type maps */
    BOOL   offset_overflow;       /* Set if too many extractions */
    BOOL   notbol;                /* NOTBOL flag */
    BOOL   noteol;                /* NOTEOL flag */
    BOOL   utf8;                  /* UTF8 flag */
    BOOL   endonly;               /* Dollar not before final \n */
    BOOL   notempty;              /* Empty string match not wanted */
    BOOL   partial;               /* PARTIAL flag */
    BOOL   hitend;                /* Hit the end of the subject at some point */
    const uschar *start_code;     /* For use when recursing */
    const uschar *start_subject;  /* Start of the subject string */
    const uschar *end_subject;    /* End of the subject string */
    const uschar *start_match;    /* Start of this match attempt */
    const uschar *end_match_ptr;  /* Subject position at end match */
    int    end_offset_top;        /* Highwater mark at end of match */
    int    capture_last;          /* Most recent capture number */
    int    start_offset;          /* The start offset value */
    recursion_info *recursive;    /* Linked list of recursion data */
    void  *callout_data;          /* To pass back to callouts */
    struct heapframe *thisframe;  /* Used only when compiling for no recursion */
  } match_data;


/* Bit definitions for entries in the pcre_ctypes table. */

  #define ctype_space   0x01
  #define ctype_letter  0x02
  #define ctype_digit   0x04
  #define ctype_xdigit  0x08
  #define ctype_word    0x10   /* alphameric or '_' */
  #define ctype_meta    0x80   /* regexp meta char or zero (end pattern) */


/* Offsets for the bitmap tables in pcre_cbits. Each table contains a set
of bits for a class map. Some classes are built by combining these tables. */

  #define cbit_space     0      /* [:space:] or \s */
  #define cbit_xdigit   32      /* [:xdigit:] */
  #define cbit_digit    64      /* [:digit:] or \d */
  #define cbit_upper    96      /* [:upper:] */
  #define cbit_lower   128      /* [:lower:] */
  #define cbit_word    160      /* [:word:] or \w */
  #define cbit_graph   192      /* [:graph:] */
  #define cbit_print   224      /* [:print:] */
  #define cbit_punct   256      /* [:punct:] */
  #define cbit_cntrl   288      /* [:cntrl:] */
  #define cbit_length  320      /* Length of the cbits table */


/* Offsets of the various tables from the base tables pointer, and
total length. */

  #define lcc_offset      0
  #define fcc_offset    256
  #define cbits_offset  512
  #define ctypes_offset (cbits_offset + cbit_length)
  #define tables_length (ctypes_offset + 256)


/* End of internal.h */

  Index: maketables.c
  ====================================================================
  /*************************************************
  *      Perl-Compatible Regular Expressions       *
  *************************************************/


/*
PCRE is a library of functions to support regular expressions whose syntax
and semantics are as close as possible to those of the Perl 5 language.

Written by: Philip Hazel <ph10@???>

             Copyright (c) 1997-2003 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 file is compiled on its own as part of the PCRE library. However,
it is also included in the compilation of dftables.c, in which case the macro
DFTABLES is defined. */

#ifndef DFTABLES
#include "internal.h"
#endif



  /*************************************************
  *           Create PCRE character tables         *
  *************************************************/


/* This function builds a set of character tables for use by PCRE and returns
a pointer to them. They are build using the ctype functions, and consequently
their contents will depend upon the current locale setting. When compiled as
part of the library, the store is obtained via pcre_malloc(), but when compiled
inside dftables, use malloc().

  Arguments:   none
  Returns:     pointer to the contiguous block of data
  */


const unsigned char *
pcre_maketables(void)
{
unsigned char *yield, *p;
int i;

#ifndef DFTABLES
yield = (unsigned char*)(pcre_malloc)(tables_length);
#else
yield = (unsigned char*)malloc(tables_length);
#endif

if (yield == NULL) return NULL;
p = yield;

/* First comes the lower casing table */

for (i = 0; i < 256; i++) *p++ = tolower(i);

/* Next the case-flipping table */

for (i = 0; i < 256; i++) *p++ = islower(i)? toupper(i) : tolower(i);

/* Then the character class tables. Don't try to be clever and save effort
on exclusive ones - in some locales things may be different. Note that the
table for "space" includes everything "isspace" gives, including VT in the
default locale. This makes it work for the POSIX class [:space:]. */

  memset(p, 0, cbit_length);
  for (i = 0; i < 256; i++)
    {
    if (isdigit(i))
      {
      p[cbit_digit  + i/8] |= 1 << (i&7);
      p[cbit_word   + i/8] |= 1 << (i&7);
      }
    if (isupper(i))
      {
      p[cbit_upper  + i/8] |= 1 << (i&7);
      p[cbit_word   + i/8] |= 1 << (i&7);
      }
    if (islower(i))
      {
      p[cbit_lower  + i/8] |= 1 << (i&7);
      p[cbit_word   + i/8] |= 1 << (i&7);
      }
    if (i == '_')   p[cbit_word   + i/8] |= 1 << (i&7);
    if (isspace(i)) p[cbit_space  + i/8] |= 1 << (i&7);
    if (isxdigit(i))p[cbit_xdigit + i/8] |= 1 << (i&7);
    if (isgraph(i)) p[cbit_graph  + i/8] |= 1 << (i&7);
    if (isprint(i)) p[cbit_print  + i/8] |= 1 << (i&7);
    if (ispunct(i)) p[cbit_punct  + i/8] |= 1 << (i&7);
    if (iscntrl(i)) p[cbit_cntrl  + i/8] |= 1 << (i&7);
    }
  p += cbit_length;


/* Finally, the character type table. In this, we exclude VT from the white
space chars, because Perl doesn't recognize it as such for \s and for comments
within regexes. */

  for (i = 0; i < 256; i++)
    {
    int x = 0;
    if (i != 0x0b && isspace(i)) x += ctype_space;
    if (isalpha(i)) x += ctype_letter;
    if (isdigit(i)) x += ctype_digit;
    if (isxdigit(i)) x += ctype_xdigit;
    if (isalnum(i) || i == '_') x += ctype_word;


    /* Note: strchr includes the terminating zero in the characters it considers.
    In this instance, that is ok because we want binary zero to be flagged as a
    meta-character, which in this sense is any character that terminates a run
    of data characters. */


    if (strchr("*+?{^.$|()[", i) != 0) x += ctype_meta; *p++ = x; }


return yield;
}

/* End of maketables.c */

  Index: pcre.c
  ====================================================================
  /*************************************************
  *      Perl-Compatible Regular Expressions       *
  *************************************************/


/*
This 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. See
the file Tech.Notes for some information on the internals.

Written by: Philip Hazel <ph10@???>

             Copyright (c) 1997-2004 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.
-----------------------------------------------------------------------------
*/


/* Define DEBUG to get debugging output on stdout. */
/* #define DEBUG */

/* Use a macro for debugging printing, 'cause that eliminates the use of #ifdef
inline, and there are *still* stupid compilers about that don't like indented
pre-processor statements. I suppose it's only been 10 years... */

#ifdef DEBUG
#define DPRINTF(p) printf p
#else
#define DPRINTF(p) /*nothing*/
#endif

/* Include the internals header, which itself includes "config.h", the Standard
C headers, and the external pcre header. */

#include "internal.h"

/* If Unicode Property support is wanted, include a private copy of the
function that does it, and the table that translates names to numbers. */

#ifdef SUPPORT_UCP
#include "ucp.c"
#include "ucptypetable.c"
#endif

/* Maximum number of items on the nested bracket stacks at compile time. This
applies to the nesting of all kinds of parentheses. It does not limit
un-nested, non-capturing parentheses. This number can be made bigger if
necessary - it is used to dimension one int and one unsigned char vector at
compile time. */

#define BRASTACK_SIZE 200


/* Maximum number of ints of offset to save on the stack for recursive calls.
If the offset vector is bigger, malloc is used. This should be a multiple of 3,
because the offset vector is always a multiple of 3 long. */

#define REC_STACK_SAVE_MAX 30


/* The maximum remaining length of subject we are prepared to search for a
req_byte match. */

#define REQ_BYTE_MAX 1000


/* Table of sizes for the fixed-length opcodes. It's defined in a macro so that
the definition is next to the definition of the opcodes in internal.h. */

static const uschar OP_lengths[] = { OP_LENGTHS };

/* Min and max values for the common repeats; for the maxima, 0 => infinity */

static const char rep_min[] = { 0, 0, 1, 1, 0, 0 };
static const char rep_max[] = { 0, 0, 0, 0, 1, 1 };

/* Table for handling escaped characters in the range '0'-'z'. Positive returns
are simple data values; negative values are for special things like \d and so
on. Zero means further processing is needed (for things like \x), or the escape
is invalid. */

  #if !EBCDIC   /* This is the "normal" table for ASCII systems */
  static const short int escapes[] = {
       0,      0,      0,      0,      0,      0,      0,      0,   /* 0 - 7 */
       0,      0,    ':',    ';',    '<',    '=',    '>',    '?',   /* 8 - ? */
     '@', -ESC_A, -ESC_B, -ESC_C, -ESC_D, -ESC_E,      0, -ESC_G,   /* @ - G */
       0,      0,      0,      0,      0,      0,      0,      0,   /* H - O */
  -ESC_P, -ESC_Q,      0, -ESC_S,      0,      0,      0, -ESC_W,   /* P - W */
  -ESC_X,      0, -ESC_Z,    '[',   '\\',    ']',    '^',    '_',   /* X - _ */
     '`',      7, -ESC_b,      0, -ESC_d,  ESC_e,  ESC_f,      0,   /* ` - g */
       0,      0,      0,      0,      0,      0,  ESC_n,      0,   /* h - o */
  -ESC_p,      0,  ESC_r, -ESC_s,  ESC_tee,    0,      0, -ESC_w,   /* p - w */
       0,      0, -ESC_z                                            /* x - z */
  };


  #else         /* This is the "abnormal" table for EBCDIC systems */
  static const short int escapes[] = {
  /*  48 */     0,     0,      0,     '.',    '<',   '(',    '+',    '|',
  /*  50 */   '&',     0,      0,       0,      0,     0,      0,      0,
  /*  58 */     0,     0,    '!',     '$',    '*',   ')',    ';',    '~',
  /*  60 */   '-',   '/',      0,       0,      0,     0,      0,      0,
  /*  68 */     0,     0,    '|',     ',',    '%',   '_',    '>',    '?',
  /*  70 */     0,     0,      0,       0,      0,     0,      0,      0,
  /*  78 */     0,   '`',    ':',     '#',    '@',  '\'',    '=',    '"',
  /*  80 */     0,     7, -ESC_b,       0, -ESC_d, ESC_e,  ESC_f,      0,
  /*  88 */     0,     0,      0,     '{',      0,     0,      0,      0,
  /*  90 */     0,     0,      0,     'l',      0, ESC_n,      0, -ESC_p,
  /*  98 */     0, ESC_r,      0,     '}',      0,     0,      0,      0,
  /*  A0 */     0,   '~', -ESC_s, ESC_tee,      0,     0, -ESC_w,      0,
  /*  A8 */     0,-ESC_z,      0,       0,      0,   '[',      0,      0,
  /*  B0 */     0,     0,      0,       0,      0,     0,      0,      0,
  /*  B8 */     0,     0,      0,       0,      0,   ']',    '=',    '-',
  /*  C0 */   '{',-ESC_A, -ESC_B,  -ESC_C, -ESC_D,-ESC_E,      0, -ESC_G,
  /*  C8 */     0,     0,      0,       0,      0,     0,      0,      0,
  /*  D0 */   '}',     0,      0,       0,      0,     0,      0, -ESC_P,
  /*  D8 */-ESC_Q,     0,      0,       0,      0,     0,      0,      0,
  /*  E0 */  '\\',     0, -ESC_S,       0,      0,     0, -ESC_W, -ESC_X,
  /*  E8 */     0,-ESC_Z,      0,       0,      0,     0,      0,      0,
  /*  F0 */     0,     0,      0,       0,      0,     0,      0,      0,
  /*  F8 */     0,     0,      0,       0,      0,     0,      0,      0
  };
  #endif



/* Tables of names of POSIX character classes and their lengths. The list is
terminated by a zero length entry. The first three must be alpha, upper, lower,
as this is assumed for handling case independence. */

  static const char *const posix_names[] = {
    "alpha", "lower", "upper",
    "alnum", "ascii", "blank", "cntrl", "digit", "graph",
    "print", "punct", "space", "word",  "xdigit" };


  static const uschar posix_name_lengths[] = {
    5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 4, 6, 0 };


/* Table of class bit maps for each POSIX class; up to three may be combined
to form the class. The table for [:blank:] is dynamically modified to remove
the vertical space characters. */

  static const int posix_class_maps[] = {
    cbit_lower, cbit_upper, -1,             /* alpha */
    cbit_lower, -1,         -1,             /* lower */
    cbit_upper, -1,         -1,             /* upper */
    cbit_digit, cbit_lower, cbit_upper,     /* alnum */
    cbit_print, cbit_cntrl, -1,             /* ascii */
    cbit_space, -1,         -1,             /* blank - a GNU extension */
    cbit_cntrl, -1,         -1,             /* cntrl */
    cbit_digit, -1,         -1,             /* digit */
    cbit_graph, -1,         -1,             /* graph */
    cbit_print, -1,         -1,             /* print */
    cbit_punct, -1,         -1,             /* punct */
    cbit_space, -1,         -1,             /* space */
    cbit_word,  -1,         -1,             /* word - a Perl extension */
    cbit_xdigit,-1,         -1              /* xdigit */
  };


/* Table to identify digits and hex digits. This is used when compiling
patterns. Note that the tables in chartables are dependent on the locale, and
may mark arbitrary characters as digits - but the PCRE compiling code expects
to handle only 0-9, a-z, and A-Z as digits when compiling. That is why we have
a private table here. It costs 256 bytes, but it is a lot faster than doing
character value tests (at least in some simple cases I timed), and in some
applications one wants PCRE to compile efficiently as well as match
efficiently.

For convenience, we use the same bit definitions as in chartables:

    0x04   decimal digit
    0x08   hexadecimal digit


Then we can use ctype_digit and ctype_xdigit in the code. */

  #if !EBCDIC    /* This is the "normal" case, for ASCII systems */
  static const unsigned char digitab[] =
    {
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*   0-  7 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*   8- 15 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  16- 23 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  24- 31 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*    - '  */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  ( - /  */
    0x0c,0x0c,0x0c,0x0c,0x0c,0x0c,0x0c,0x0c, /*  0 - 7  */
    0x0c,0x0c,0x00,0x00,0x00,0x00,0x00,0x00, /*  8 - ?  */
    0x00,0x08,0x08,0x08,0x08,0x08,0x08,0x00, /*  @ - G  */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  H - O  */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  P - W  */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  X - _  */
    0x00,0x08,0x08,0x08,0x08,0x08,0x08,0x00, /*  ` - g  */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  h - o  */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  p - w  */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  x -127 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 128-135 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 136-143 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 144-151 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 152-159 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 160-167 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 168-175 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 176-183 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 184-191 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 192-199 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 200-207 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 208-215 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 216-223 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 224-231 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 232-239 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 240-247 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};/* 248-255 */


  #else          /* This is the "abnormal" case, for EBCDIC systems */
  static const unsigned char digitab[] =
    {
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*   0-  7  0 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*   8- 15    */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  16- 23 10 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  24- 31    */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  32- 39 20 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  40- 47    */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  48- 55 30 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  56- 63    */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*    - 71 40 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  72- |     */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  & - 87 50 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  88- ¬     */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  - -103 60 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 104- ?     */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 112-119 70 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 120- "     */
    0x00,0x08,0x08,0x08,0x08,0x08,0x08,0x00, /* 128- g  80 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  h -143    */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 144- p  90 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  q -159    */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 160- x  A0 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  y -175    */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  ^ -183 B0 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 184-191    */
    0x00,0x08,0x08,0x08,0x08,0x08,0x08,0x00, /*  { - G  C0 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  H -207    */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  } - P  D0 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  Q -223    */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  \ - X  E0 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  Y -239    */
    0x0c,0x0c,0x0c,0x0c,0x0c,0x0c,0x0c,0x0c, /*  0 - 7  F0 */
    0x0c,0x0c,0x00,0x00,0x00,0x00,0x00,0x00};/*  8 -255    */


  static const unsigned char ebcdic_chartab[] = { /* chartable partial dup */
    0x80,0x00,0x00,0x00,0x00,0x01,0x00,0x00, /*   0-  7 */
    0x00,0x00,0x00,0x00,0x01,0x01,0x00,0x00, /*   8- 15 */
    0x00,0x00,0x00,0x00,0x00,0x01,0x00,0x00, /*  16- 23 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  24- 31 */
    0x00,0x00,0x00,0x00,0x00,0x01,0x00,0x00, /*  32- 39 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  40- 47 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  48- 55 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  56- 63 */
    0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*    - 71 */
    0x00,0x00,0x00,0x80,0x00,0x80,0x80,0x80, /*  72- |  */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  & - 87 */
    0x00,0x00,0x00,0x80,0x80,0x80,0x00,0x00, /*  88- ¬  */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  - -103 */
    0x00,0x00,0x00,0x00,0x00,0x10,0x00,0x80, /* 104- ?  */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 112-119 */
    0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 120- "  */
    0x00,0x1a,0x1a,0x1a,0x1a,0x1a,0x1a,0x12, /* 128- g  */
    0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /*  h -143 */
    0x00,0x12,0x12,0x12,0x12,0x12,0x12,0x12, /* 144- p  */
    0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /*  q -159 */
    0x00,0x00,0x12,0x12,0x12,0x12,0x12,0x12, /* 160- x  */
    0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /*  y -175 */
    0x80,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*  ^ -183 */
    0x00,0x00,0x80,0x00,0x00,0x00,0x00,0x00, /* 184-191 */
    0x80,0x1a,0x1a,0x1a,0x1a,0x1a,0x1a,0x12, /*  { - G  */
    0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /*  H -207 */
    0x00,0x12,0x12,0x12,0x12,0x12,0x12,0x12, /*  } - P  */
    0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /*  Q -223 */
    0x00,0x00,0x12,0x12,0x12,0x12,0x12,0x12, /*  \ - X  */
    0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /*  Y -239 */
    0x1c,0x1c,0x1c,0x1c,0x1c,0x1c,0x1c,0x1c, /*  0 - 7  */
    0x1c,0x1c,0x00,0x00,0x00,0x00,0x00,0x00};/*  8 -255 */
  #endif



/* Definition to allow mutual recursion */

  static BOOL
    compile_regex(int, int, int *, uschar **, const uschar **, const char **,
      BOOL, int, int *, int *, branch_chain *, compile_data *);


/* Structure for building a chain of data that actually lives on the
stack, for holding the values of the subject pointer at the start of each
subpattern, so as to detect when an empty string has been matched by a
subpattern - to break infinite loops. When NO_RECURSE is set, these blocks
are on the heap, not on the stack. */

  typedef struct eptrblock {
    struct eptrblock *epb_prev;
    const uschar *epb_saved_eptr;
  } eptrblock;


/* Flag bits for the match() function */

  #define match_condassert   0x01    /* Called to check a condition assertion */
  #define match_isgroup      0x02    /* Set if start of bracketed group */


/* Non-error returns from the match() function. Error returns are externally
defined PCRE_ERROR_xxx codes, which are all negative. */

  #define MATCH_MATCH        1
  #define MATCH_NOMATCH      0




  /*************************************************
  *               Global variables                 *
  *************************************************/


/* PCRE is thread-clean and doesn't use any global variables in the normal
sense. However, it calls memory allocation and free functions via the four
indirections below, and it can optionally do callouts. These values can be
changed by the caller, but are shared between all threads. However, when
compiling for Virtual Pascal, things are done differently (see pcre.in). */

#ifndef VPCOMPAT
#ifdef __cplusplus
extern "C" void *(*pcre_malloc)(size_t) = malloc;
extern "C" void (*pcre_free)(void *) = free;
extern "C" void *(*pcre_stack_malloc)(size_t) = malloc;
extern "C" void (*pcre_stack_free)(void *) = free;
extern "C" int (*pcre_callout)(pcre_callout_block *) = NULL;
#else
void *(*pcre_malloc)(size_t) = malloc;
void (*pcre_free)(void *) = free;
void *(*pcre_stack_malloc)(size_t) = malloc;
void (*pcre_stack_free)(void *) = free;
int (*pcre_callout)(pcre_callout_block *) = NULL;
#endif
#endif


  /*************************************************
  *    Macros and tables for character handling    *
  *************************************************/


/* When UTF-8 encoding is being used, a character is no longer just a single
byte. The macros for character handling generate simple sequences when used in
byte-mode, and more complicated ones for UTF-8 characters. */

#ifndef SUPPORT_UTF8
#define GETCHAR(c, eptr) c = *eptr;
#define GETCHARINC(c, eptr) c = *eptr++;
#define GETCHARINCTEST(c, eptr) c = *eptr++;
#define GETCHARLEN(c, eptr, len) c = *eptr;
#define BACKCHAR(eptr)

#else /* SUPPORT_UTF8 */

/* Get the next UTF-8 character, not advancing the pointer. This is called when
we know we are in UTF-8 mode. */

  #define GETCHAR(c, eptr) \
    c = *eptr; \
    if ((c & 0xc0) == 0xc0) \
      { \
      int gcii; \
      int gcaa = utf8_table4[c & 0x3f];  /* Number of additional bytes */ \
      int gcss = 6*gcaa; \
      c = (c & utf8_table3[gcaa]) << gcss; \
      for (gcii = 1; gcii <= gcaa; gcii++) \
        { \
        gcss -= 6; \
        c |= (eptr[gcii] & 0x3f) << gcss; \
        } \
      }


/* Get the next UTF-8 character, advancing the pointer. This is called when we
know we are in UTF-8 mode. */

  #define GETCHARINC(c, eptr) \
    c = *eptr++; \
    if ((c & 0xc0) == 0xc0) \
      { \
      int gcaa = utf8_table4[c & 0x3f];  /* Number of additional bytes */ \
      int gcss = 6*gcaa; \
      c = (c & utf8_table3[gcaa]) << gcss; \
      while (gcaa-- > 0) \
        { \
        gcss -= 6; \
        c |= (*eptr++ & 0x3f) << gcss; \
        } \
      }


/* Get the next character, testing for UTF-8 mode, and advancing the pointer */

  #define GETCHARINCTEST(c, eptr) \
    c = *eptr++; \
    if (md->utf8 && (c & 0xc0) == 0xc0) \
      { \
      int gcaa = utf8_table4[c & 0x3f];  /* Number of additional bytes */ \
      int gcss = 6*gcaa; \
      c = (c & utf8_table3[gcaa]) << gcss; \
      while (gcaa-- > 0) \
        { \
        gcss -= 6; \
        c |= (*eptr++ & 0x3f) << gcss; \
        } \
      }


/* Get the next UTF-8 character, not advancing the pointer, incrementing length
if there are extra bytes. This is called when we know we are in UTF-8 mode. */

  #define GETCHARLEN(c, eptr, len) \
    c = *eptr; \
    if ((c & 0xc0) == 0xc0) \
      { \
      int gcii; \
      int gcaa = utf8_table4[c & 0x3f];  /* Number of additional bytes */ \
      int gcss = 6*gcaa; \
      c = (c & utf8_table3[gcaa]) << gcss; \
      for (gcii = 1; gcii <= gcaa; gcii++) \
        { \
        gcss -= 6; \
        c |= (eptr[gcii] & 0x3f) << gcss; \
        } \
      len += gcaa; \
      }


/* If the pointer is not at the start of a character, move it back until
it is. Called only in UTF-8 mode. */

#define BACKCHAR(eptr) while((*eptr & 0xc0) == 0x80) eptr--;

#endif



  /*************************************************
  *             Default character tables           *
  *************************************************/


/* A default set of character tables is included in the PCRE binary. Its source
is built by the maketables auxiliary program, which uses the default C ctypes
functions, and put in the file chartables.c. These tables are used by PCRE
whenever the caller of pcre_compile() does not provide an alternate set of
tables. */

#include "chartables.c"



  #ifdef SUPPORT_UTF8
  /*************************************************
  *           Tables for UTF-8 support             *
  *************************************************/


/* These are the breakpoints for different numbers of bytes in a UTF-8
character. */

  static const int utf8_table1[] =
    { 0x7f, 0x7ff, 0xffff, 0x1fffff, 0x3ffffff, 0x7fffffff};


/* These are the indicator bits and the mask for the data bits to set in the
first byte of a character, indexed by the number of additional bytes. */

  static const int utf8_table2[] = { 0,    0xc0, 0xe0, 0xf0, 0xf8, 0xfc};
  static const int utf8_table3[] = { 0xff, 0x1f, 0x0f, 0x07, 0x03, 0x01};


/* Table of the number of extra characters, indexed by the first character
masked with 0x3f. The highest number for a valid UTF-8 character is in fact
0x3d. */

  static const uschar utf8_table4[] = {
    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
    2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
    3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 };



  /*************************************************
  *       Convert character value to UTF-8         *
  *************************************************/


/* This function takes an integer value in the range 0 - 0x7fffffff
and encodes it as a UTF-8 character in 0 to 6 bytes.

  Arguments:
    cvalue     the character value
    buffer     pointer to buffer for result - at least 6 bytes long


  Returns:     number of characters placed in the buffer
  */


  static int
  ord2utf8(int cvalue, uschar *buffer)
  {
  register int i, j;
  for (i = 0; i < sizeof(utf8_table1)/sizeof(int); i++)
    if (cvalue <= utf8_table1[i]) break;
  buffer += i;
  for (j = i; j > 0; j--)
   {
   *buffer-- = 0x80 | (cvalue & 0x3f);
   cvalue >>= 6;
   }
  *buffer = utf8_table2[i] | cvalue;
  return i + 1;
  }
  #endif




  /*************************************************
  *         Print compiled regex                   *
  *************************************************/


/* The code for doing this is held in a separate file that is also included in
pcretest.c. It defines a function called print_internals(). */

#ifdef DEBUG
#include "printint.c"
#endif



  /*************************************************
  *          Return version string                 *
  *************************************************/


#define STRING(a) # a
#define XSTRING(s) STRING(s)

EXPORT const char *
pcre_version(void)
{
return XSTRING(PCRE_MAJOR) "." XSTRING(PCRE_MINOR) " " XSTRING(PCRE_DATE);
}




  /*************************************************
  *         Flip bytes in an integer               *
  *************************************************/


/* This function is called when the magic number in a regex doesn't match in
order to flip its bytes to see if we are dealing with a pattern that was
compiled on a host of different endianness. If so, this function is used to
flip other byte values.

  Arguments:
    value        the number to flip
    n            the number of bytes to flip (assumed to be 2 or 4)


  Returns:       the flipped value
  */


  static long int
  byteflip(long int value, int n)
  {
  if (n == 2) return ((value & 0x00ff) << 8) | ((value & 0xff00) >> 8);
  return ((value & 0x000000ff) << 24) |
         ((value & 0x0000ff00) <<  8) |
         ((value & 0x00ff0000) >>  8) |
         ((value & 0xff000000) >> 24);
  }




  /*************************************************
  *       Test for a byte-flipped compiled regex   *
  *************************************************/


/* This function is called from pce_exec() and also from pcre_fullinfo(). Its
job is to test whether the regex is byte-flipped - that is, it was compiled on
a system of opposite endianness. The function is called only when the native
MAGIC_NUMBER test fails. If the regex is indeed flipped, we flip all the
relevant values into a different data block, and return it.

  Arguments:
    re               points to the regex
    study            points to study data, or NULL
    internal_re      points to a new regex block
    internal_study   points to a new study block


  Returns:           the new block if is is indeed a byte-flipped regex
                     NULL if it is not
  */


  static real_pcre *
  try_flipped(const real_pcre *re, real_pcre *internal_re,
    const pcre_study_data *study, pcre_study_data *internal_study)
  {
  if (byteflip(re->magic_number, sizeof(re->magic_number)) != MAGIC_NUMBER)
    return NULL;


  *internal_re = *re;           /* To copy other fields */
  internal_re->size = byteflip(re->size, sizeof(re->size));
  internal_re->options = byteflip(re->options, sizeof(re->options));
  internal_re->top_bracket = byteflip(re->top_bracket, sizeof(re->top_bracket));
  internal_re->top_backref = byteflip(re->top_backref, sizeof(re->top_backref));
  internal_re->first_byte = byteflip(re->first_byte, sizeof(re->first_byte));
  internal_re->req_byte = byteflip(re->req_byte, sizeof(re->req_byte));
  internal_re->name_table_offset = byteflip(re->name_table_offset,
    sizeof(re->name_table_offset));
  internal_re->name_entry_size = byteflip(re->name_entry_size,
    sizeof(re->name_entry_size));
  internal_re->name_count = byteflip(re->name_count, sizeof(re->name_count));


  if (study != NULL)
    {
    *internal_study = *study;   /* To copy other fields */
    internal_study->size = byteflip(study->size, sizeof(study->size));
    internal_study->options = byteflip(study->options, sizeof(study->options));
    }


return internal_re;
}



/*************************************************
* (Obsolete) Return info about compiled pattern *
*************************************************/

/* This is the original "info" function. It picks potentially useful data out
of the private structure, but its interface was too rigid. It remains for
backwards compatibility. The public options are passed back in an int - though
the re->options field has been expanded to a long int, all the public options
at the low end of it, and so even on 16-bit systems this will still be OK.
Therefore, I haven't changed the API for pcre_info().

  Arguments:
    argument_re   points to compiled code
    optptr        where to pass back the options
    first_byte    where to pass back the first character,
                  or -1 if multiline and all branches start ^,
                  or -2 otherwise


  Returns:        number of capturing subpatterns
                  or negative values on error
  */


  EXPORT int
  pcre_info(const pcre *argument_re, int *optptr, int *first_byte)
  {
  real_pcre internal_re;
  const real_pcre *re = (const real_pcre *)argument_re;
  if (re == NULL) return PCRE_ERROR_NULL;
  if (re->magic_number != MAGIC_NUMBER)
    {
    re = try_flipped(re, &internal_re, NULL, NULL);
    if (re == NULL) return PCRE_ERROR_BADMAGIC;
    }
  if (optptr != NULL) *optptr = (int)(re->options & PUBLIC_OPTIONS);
  if (first_byte != NULL)
    *first_byte = ((re->options & PCRE_FIRSTSET) != 0)? re->first_byte :
       ((re->options & PCRE_STARTLINE) != 0)? -1 : -2;
  return re->top_bracket;
  }




  /*************************************************
  *        Return info about compiled pattern      *
  *************************************************/


/* This is a newer "info" function which has an extensible interface so
that additional items can be added compatibly.

  Arguments:
    argument_re      points to compiled code
    extra_data       points extra data, or NULL
    what             what information is required
    where            where to put the information


  Returns:           0 if data returned, negative on error
  */


  EXPORT int
  pcre_fullinfo(const pcre *argument_re, const pcre_extra *extra_data, int what,
    void *where)
  {
  real_pcre internal_re;
  pcre_study_data internal_study;
  const real_pcre *re = (const real_pcre *)argument_re;
  const pcre_study_data *study = NULL;


if (re == NULL || where == NULL) return PCRE_ERROR_NULL;

  if (extra_data != NULL && (extra_data->flags & PCRE_EXTRA_STUDY_DATA) != 0)
    study = (const pcre_study_data *)extra_data->study_data;


  if (re->magic_number != MAGIC_NUMBER)
    {
    re = try_flipped(re, &internal_re, study, &internal_study);
    if (re == NULL) return PCRE_ERROR_BADMAGIC;
    if (study != NULL) study = &internal_study;
    }


  switch (what)
    {
    case PCRE_INFO_OPTIONS:
    *((unsigned long int *)where) = re->options & PUBLIC_OPTIONS;
    break;


    case PCRE_INFO_SIZE:
    *((size_t *)where) = re->size;
    break;


    case PCRE_INFO_STUDYSIZE:
    *((size_t *)where) = (study == NULL)? 0 : study->size;
    break;


    case PCRE_INFO_CAPTURECOUNT:
    *((int *)where) = re->top_bracket;
    break;


    case PCRE_INFO_BACKREFMAX:
    *((int *)where) = re->top_backref;
    break;


    case PCRE_INFO_FIRSTBYTE:
    *((int *)where) =
      ((re->options & PCRE_FIRSTSET) != 0)? re->first_byte :
      ((re->options & PCRE_STARTLINE) != 0)? -1 : -2;
    break;


    /* Make sure we pass back the pointer to the bit vector in the external
    block, not the internal copy (with flipped integer fields). */


    case PCRE_INFO_FIRSTTABLE:
    *((const uschar **)where) =
      (study != NULL && (study->options & PCRE_STUDY_MAPPED) != 0)?
        ((const pcre_study_data *)extra_data->study_data)->start_bits : NULL;
    break;


    case PCRE_INFO_LASTLITERAL:
    *((int *)where) =
      ((re->options & PCRE_REQCHSET) != 0)? re->req_byte : -1;
    break;


    case PCRE_INFO_NAMEENTRYSIZE:
    *((int *)where) = re->name_entry_size;
    break;


    case PCRE_INFO_NAMECOUNT:
    *((int *)where) = re->name_count;
    break;


    case PCRE_INFO_NAMETABLE:
    *((const uschar **)where) = (const uschar *)re + re->name_table_offset;
    break;


    case PCRE_INFO_DEFAULT_TABLES:
    *((const uschar **)where) = (const uschar *)pcre_default_tables;
    break;


    default: return PCRE_ERROR_BADOPTION;
    }


return 0;
}



/*************************************************
* Return info about what features are configured *
*************************************************/

/* This is function which has an extensible interface so that additional items
can be added compatibly.

  Arguments:
    what             what information is required
    where            where to put the information


  Returns:           0 if data returned, negative on error
  */


  EXPORT int
  pcre_config(int what, void *where)
  {
  switch (what)
    {
    case PCRE_CONFIG_UTF8:
  #ifdef SUPPORT_UTF8
    *((int *)where) = 1;
  #else
    *((int *)where) = 0;
  #endif
    break;


    case PCRE_CONFIG_UNICODE_PROPERTIES:
  #ifdef SUPPORT_UCP
    *((int *)where) = 1;
  #else
    *((int *)where) = 0;
  #endif
    break;


    case PCRE_CONFIG_NEWLINE:
    *((int *)where) = NEWLINE;
    break;


    case PCRE_CONFIG_LINK_SIZE:
    *((int *)where) = LINK_SIZE;
    break;


    case PCRE_CONFIG_POSIX_MALLOC_THRESHOLD:
    *((int *)where) = POSIX_MALLOC_THRESHOLD;
    break;


    case PCRE_CONFIG_MATCH_LIMIT:
    *((unsigned int *)where) = MATCH_LIMIT;
    break;


    case PCRE_CONFIG_STACKRECURSE:
  #ifdef NO_RECURSE
    *((int *)where) = 0;
  #else
    *((int *)where) = 1;
  #endif
    break;


    default: return PCRE_ERROR_BADOPTION;
    }


return 0;
}



  #ifdef DEBUG
  /*************************************************
  *        Debugging function to print chars       *
  *************************************************/


/* Print a sequence of chars in printable format, stopping at the end of the
subject if the requested.

  Arguments:
    p           points to characters
    length      number to print
    is_subject  TRUE if printing from within md->start_subject
    md          pointer to matching data block, if is_subject is TRUE


  Returns:     nothing
  */


  static void
  pchars(const uschar *p, int length, BOOL is_subject, match_data *md)
  {
  int c;
  if (is_subject && length > md->end_subject - p) length = md->end_subject - p;
  while (length-- > 0)
    if (isprint(c = *(p++))) printf("%c", c); else printf("\\x%02x", c);
  }
  #endif





  /*************************************************
  *            Handle escapes                      *
  *************************************************/


/* This function is called when a \ has been encountered. It either returns a
positive value for a simple escape such as \n, or a negative value which
encodes one of the more complicated things such as \d. When UTF-8 is enabled,
a positive value greater than 255 may be returned. On entry, ptr is pointing at
the \. On exit, it is on the final character of the escape sequence.

  Arguments:
    ptrptr     points to the pattern position pointer
    errorptr   points to the pointer to the error message
    bracount   number of previous extracting brackets
    options    the options bits
    isclass    TRUE if inside a character class


  Returns:     zero or positive => a data character
               negative => a special escape sequence
               on error, errorptr is set
  */


  static int
  check_escape(const uschar **ptrptr, const char **errorptr, int bracount,
    int options, BOOL isclass)
  {
  const uschar *ptr = *ptrptr;
  int c, i;


/* If backslash is at the end of the pattern, it's an error. */

c = *(++ptr);
if (c == 0) *errorptr = ERR1;

/* Non-alphamerics are literals. For digits or letters, do an initial lookup in
a table. A non-zero result is something that can be returned immediately.
Otherwise further processing may be required. */

  #if !EBCDIC    /* ASCII coding */
  else if (c < '0' || c > 'z') {}                           /* Not alphameric */
  else if ((i = escapes[c - '0']) != 0) c = i;


  #else          /* EBCDIC coding */
  else if (c < 'a' || (ebcdic_chartab[c] & 0x0E) == 0) {}   /* Not alphameric */
  else if ((i = escapes[c - 0x48]) != 0)  c = i;
  #endif


/* Escapes that need further processing, or are illegal. */

  else
    {
    const uschar *oldptr;
    switch (c)
      {
      /* A number of Perl escapes are not handled by PCRE. We give an explicit
      error. */


      case 'l':
      case 'L':
      case 'N':
      case 'u':
      case 'U':
      *errorptr = ERR37;
      break;


      /* The handling of escape sequences consisting of a string of digits
      starting with one that is not zero is not straightforward. By experiment,
      the way Perl works seems to be as follows:


      Outside a character class, the digits are read as a decimal number. If the
      number is less than 10, or if there are that many previous extracting
      left brackets, then it is a back reference. Otherwise, up to three octal
      digits are read to form an escaped byte. Thus \123 is likely to be octal
      123 (cf \0123, which is octal 012 followed by the literal 3). If the octal
      value is greater than 377, the least significant 8 bits are taken. Inside a
      character class, \ followed by a digit is always an octal number. */


      case '1': case '2': case '3': case '4': case '5':
      case '6': case '7': case '8': case '9':


      if (!isclass)
        {
        oldptr = ptr;
        c -= '0';
        while ((digitab[ptr[1]] & ctype_digit) != 0)
          c = c * 10 + *(++ptr) - '0';
        if (c < 10 || c <= bracount)
          {
          c = -(ESC_REF + c);
          break;
          }
        ptr = oldptr;      /* Put the pointer back and fall through */
        }


      /* Handle an octal number following \. If the first digit is 8 or 9, Perl
      generates a binary zero byte and treats the digit as a following literal.
      Thus we have to pull back the pointer by one. */


      if ((c = *ptr) >= '8')
        {
        ptr--;
        c = 0;
        break;
        }


      /* \0 always starts an octal number, but we may drop through to here with a
      larger first octal digit. */


      case '0':
      c -= '0';
      while(i++ < 2 && ptr[1] >= '0' && ptr[1] <= '7')
          c = c * 8 + *(++ptr) - '0';
      c &= 255;     /* Take least significant 8 bits */
      break;


      /* \x is complicated when UTF-8 is enabled. \x{ddd} is a character number
      which can be greater than 0xff, but only if the ddd are hex digits. */


      case 'x':
  #ifdef SUPPORT_UTF8
      if (ptr[1] == '{' && (options & PCRE_UTF8) != 0)
        {
        const uschar *pt = ptr + 2;
        register int count = 0;
        c = 0;
        while ((digitab[*pt] & ctype_xdigit) != 0)
          {
          int cc = *pt++;
          count++;
  #if !EBCDIC    /* ASCII coding */
          if (cc >= 'a') cc -= 32;               /* Convert to upper case */
          c = c * 16 + cc - ((cc < 'A')? '0' : ('A' - 10));
  #else          /* EBCDIC coding */
          if (cc >= 'a' && cc <= 'z') cc += 64;  /* Convert to upper case */
          c = c * 16 + cc - ((cc >= '0')? '0' : ('A' - 10));
  #endif
          }
        if (*pt == '}')
          {
          if (c < 0 || count > 8) *errorptr = ERR34;
          ptr = pt;
          break;
          }
        /* If the sequence of hex digits does not end with '}', then we don't
        recognize this construct; fall through to the normal \x handling. */
        }
  #endif


      /* Read just a single hex char */


      c = 0;
      while (i++ < 2 && (digitab[ptr[1]] & ctype_xdigit) != 0)
        {
        int cc;                               /* Some compilers don't like ++ */
        cc = *(++ptr);                        /* in initializers */
  #if !EBCDIC    /* ASCII coding */
        if (cc >= 'a') cc -= 32;              /* Convert to upper case */
        c = c * 16 + cc - ((cc < 'A')? '0' : ('A' - 10));
  #else          /* EBCDIC coding */
        if (cc <= 'z') cc += 64;              /* Convert to upper case */
        c = c * 16 + cc - ((cc >= '0')? '0' : ('A' - 10));
  #endif
        }
      break;


      /* Other special escapes not starting with a digit are straightforward */


      case 'c':
      c = *(++ptr);
      if (c == 0)
        {
        *errorptr = ERR2;
        return 0;
        }


      /* A letter is upper-cased; then the 0x40 bit is flipped. This coding
      is ASCII-specific, but then the whole concept of \cx is ASCII-specific.
      (However, an EBCDIC equivalent has now been added.) */


  #if !EBCDIC    /* ASCII coding */
      if (c >= 'a' && c <= 'z') c -= 32;
      c ^= 0x40;
  #else          /* EBCDIC coding */
      if (c >= 'a' && c <= 'z') c += 64;
      c ^= 0xC0;
  #endif
      break;


      /* PCRE_EXTRA enables extensions to Perl in the matter of escapes. Any
      other alphameric following \ is an error if PCRE_EXTRA was set; otherwise,
      for Perl compatibility, it is a literal. This code looks a bit odd, but
      there used to be some cases other than the default, and there may be again
      in future, so I haven't "optimized" it. */


      default:
      if ((options & PCRE_EXTRA) != 0) switch(c)
        {
        default:
        *errorptr = ERR3;
        break;
        }
      break;
      }
    }


*ptrptr = ptr;
return c;
}



  #ifdef SUPPORT_UCP
  /*************************************************
  *               Handle \P and \p                 *
  *************************************************/


/* This function is called after \P or \p has been encountered, provided that
PCRE is compiled with support for Unicode properties. On entry, ptrptr is
pointing at the P or p. On exit, it is pointing at the final character of the
escape sequence.

  Argument:
    ptrptr     points to the pattern position pointer
    negptr     points to a boolean that is set TRUE for negation else FALSE
    errorptr   points to the pointer to the error message


  Returns:     value from ucp_type_table, or -1 for an invalid type
  */


static int
get_ucp(const uschar **ptrptr, BOOL *negptr, const char **errorptr)
{
int c, i, bot, top;
const uschar *ptr = *ptrptr;
char name[4];

c = *(++ptr);
if (c == 0) goto ERROR_RETURN;

*negptr = FALSE;

/* \P or \p can be followed by a one- or two-character name in {}, optionally
preceded by ^ for negation. */

  if (c == '{')
    {
    if (ptr[1] == '^')
      {
      *negptr = TRUE;
      ptr++;
      }
    for (i = 0; i <= 2; i++)
      {
      c = *(++ptr);
      if (c == 0) goto ERROR_RETURN;
      if (c == '}') break;
      name[i] = c;
      }
    if (c !='}')   /* Try to distinguish error cases */
      {
      while (*(++ptr) != 0 && *ptr != '}');
      if (*ptr == '}') goto UNKNOWN_RETURN; else goto ERROR_RETURN;
      }
    name[i] = 0;
    }


/* Otherwise there is just one following character */

  else
    {
    name[0] = c;
    name[1] = 0;
    }


*ptrptr = ptr;

/* Search for a recognized property name using binary chop */

bot = 0;
top = sizeof(utt)/sizeof(ucp_type_table);

  while (bot < top)
    {
    i = (bot + top)/2;
    c = strcmp(name, utt[i].name);
    if (c == 0) return utt[i].value;
    if (c > 0) bot = i + 1; else top = i;
    }


UNKNOWN_RETURN:
*errorptr = ERR47;
*ptrptr = ptr;
return -1;

ERROR_RETURN:
*errorptr = ERR46;
*ptrptr = ptr;
return -1;
}
#endif




  /*************************************************
  *            Check for counted repeat            *
  *************************************************/


/* This function is called when a '{' is encountered in a place where it might
start a quantifier. It looks ahead to see if it really is a quantifier or not.
It is only a quantifier if it is one of the forms {ddd} {ddd,} or {ddd,ddd}
where the ddds are digits.

  Arguments:
    p         pointer to the first char after '{'


  Returns:    TRUE or FALSE
  */


static BOOL
is_counted_repeat(const uschar *p)
{
if ((digitab[*p++] & ctype_digit) == 0) return FALSE;
while ((digitab[*p] & ctype_digit) != 0) p++;
if (*p == '}') return TRUE;

if (*p++ != ',') return FALSE;
if (*p == '}') return TRUE;

if ((digitab[*p++] & ctype_digit) == 0) return FALSE;
while ((digitab[*p] & ctype_digit) != 0) p++;

return (*p == '}');
}



  /*************************************************
  *         Read repeat counts                     *
  *************************************************/


/* Read an item of the form {n,m} and return the values. This is called only
after is_counted_repeat() has confirmed that a repeat-count quantifier exists,
so the syntax is guaranteed to be correct, but we need to check the values.

  Arguments:
    p          pointer to first char after '{'
    minp       pointer to int for min
    maxp       pointer to int for max
               returned as -1 if no max
    errorptr   points to pointer to error message


  Returns:     pointer to '}' on success;
               current ptr on error, with errorptr set
  */


static const uschar *
read_repeat_counts(const uschar *p, int *minp, int *maxp, const char **errorptr)
{
int min = 0;
int max = -1;

while ((digitab[*p] & ctype_digit) != 0) min = min * 10 + *p++ - '0';

  if (*p == '}') max = min; else
    {
    if (*(++p) != '}')
      {
      max = 0;
      while((digitab[*p] & ctype_digit) != 0) max = max * 10 + *p++ - '0';
      if (max < min)
        {
        *errorptr = ERR4;
        return p;
        }
      }
    }


/* Do paranoid checks, then fill in the required variables, and pass back the
pointer to the terminating '}'. */

  if (min > 65535 || max > 65535)
    *errorptr = ERR5;
  else
    {
    *minp = min;
    *maxp = max;
    }
  return p;
  }




  /*************************************************
  *      Find first significant op code            *
  *************************************************/


/* This is called by several functions that scan a compiled expression looking
for a fixed first character, or an anchoring op code etc. It skips over things
that do not influence this. For some calls, a change of option is important.
For some calls, it makes sense to skip negative forward and all backward
assertions, and also the \b assertion; for others it does not.

  Arguments:
    code         pointer to the start of the group
    options      pointer to external options
    optbit       the option bit whose changing is significant, or
                   zero if none are
    skipassert   TRUE if certain assertions are to be skipped


  Returns:       pointer to the first significant opcode
  */


  static const uschar*
  first_significant_code(const uschar *code, int *options, int optbit,
    BOOL skipassert)
  {
  for (;;)
    {
    switch ((int)*code)
      {
      case OP_OPT:
      if (optbit > 0 && ((int)code[1] & optbit) != (*options & optbit))
        *options = (int)code[1];
      code += 2;
      break;


      case OP_ASSERT_NOT:
      case OP_ASSERTBACK:
      case OP_ASSERTBACK_NOT:
      if (!skipassert) return code;
      do code += GET(code, 1); while (*code == OP_ALT);
      code += OP_lengths[*code];
      break;


      case OP_WORD_BOUNDARY:
      case OP_NOT_WORD_BOUNDARY:
      if (!skipassert) return code;
      /* Fall through */


      case OP_CALLOUT:
      case OP_CREF:
      case OP_BRANUMBER:
      code += OP_lengths[*code];
      break;


      default:
      return code;
      }
    }
  /* Control never reaches here */
  }





  /*************************************************
  *        Find the fixed length of a pattern      *
  *************************************************/


/* Scan a pattern and compute the fixed length of subject that will match it,
if the length is fixed. This is needed for dealing with backward assertions.
In UTF8 mode, the result is in characters rather than bytes.

  Arguments:
    code     points to the start of the pattern (the bracket)
    options  the compiling options


  Returns:   the fixed length, or -1 if there is no fixed length,
               or -2 if \C was encountered
  */


static int
find_fixedlength(uschar *code, int options)
{
int length = -1;

register int branchlength = 0;
register uschar *cc = code + 1 + LINK_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;
    register int op = *cc;
    if (op >= OP_BRA) op = OP_BRA;


    switch (op)
      {
      case OP_BRA:
      case OP_ONCE:
      case OP_COND:
      d = find_fixedlength(cc, options);
      if (d < 0) return d;
      branchlength += d;
      do cc += GET(cc, 1); while (*cc == OP_ALT);
      cc += 1 + LINK_SIZE;
      break;


      /* 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. */


      case OP_ALT:
      case OP_KET:
      case OP_KETRMAX:
      case OP_KETRMIN:
      case OP_END:
      if (length < 0) length = branchlength;
        else if (length != branchlength) return -1;
      if (*cc != OP_ALT) return length;
      cc += 1 + LINK_SIZE;
      branchlength = 0;
      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_BRANUMBER:
      case OP_CREF:
      case OP_OPT:
      case OP_CALLOUT:
      case OP_SOD:
      case OP_SOM:
      case OP_EOD:
      case OP_EODN:
      case OP_CIRC:
      case OP_DOLL:
      case OP_NOT_WORD_BOUNDARY:
      case OP_WORD_BOUNDARY:
      cc += OP_lengths[*cc];
      break;


      /* Handle literal characters */


      case OP_CHAR:
      case OP_CHARNC:
      branchlength++;
      cc += 2;
  #ifdef SUPPORT_UTF8
      if ((options & PCRE_UTF8) != 0)
        {
        while ((*cc & 0xc0) == 0x80) cc++;
        }
  #endif
      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:
      branchlength += GET2(cc,1);
      cc += 4;
  #ifdef SUPPORT_UTF8
      if ((options & PCRE_UTF8) != 0)
        {
        while((*cc & 0x80) == 0x80) cc++;
        }
  #endif
      break;


      case OP_TYPEEXACT:
      branchlength += GET2(cc,1);
      cc += 4;
      break;


      /* Handle single-char matchers */


      case OP_PROP:
      case OP_NOTPROP:
      cc++;
      /* 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:
      branchlength++;
      cc++;
      break;


      /* The single-byte matcher isn't allowed */


      case OP_ANYBYTE:
      return -2;


      /* Check a class for variable quantification */


  #ifdef SUPPORT_UTF8
      case OP_XCLASS:
      cc += GET(cc, 1) - 33;
      /* Fall through */
  #endif


      case OP_CLASS:
      case OP_NCLASS:
      cc += 33;


      switch (*cc)
        {
        case OP_CRSTAR:
        case OP_CRMINSTAR:
        case OP_CRQUERY:
        case OP_CRMINQUERY:
        return -1;


        case OP_CRRANGE:
        case OP_CRMINRANGE:
        if (GET2(cc,1) != GET2(cc,3)) return -1;
        branchlength += GET2(cc,1);
        cc += 5;
        break;


        default:
        branchlength++;
        }
      break;


      /* Anything else is variable length */


      default:
      return -1;
      }
    }
  /* Control never gets here */
  }





  /*************************************************
  *    Scan compiled regex for numbered bracket    *
  *************************************************/


/* This little function scans through a compiled pattern until it finds a
capturing bracket with the given number.

  Arguments:
    code        points to start of expression
    utf8        TRUE in UTF-8 mode
    number      the required bracket number


  Returns:      pointer to the opcode for the bracket, or NULL if not found
  */


  static const uschar *
  find_bracket(const uschar *code, BOOL utf8, int number)
  {
  #ifndef SUPPORT_UTF8
  utf8 = utf8;               /* Stop pedantic compilers complaining */
  #endif


  for (;;)
    {
    register int c = *code;
    if (c == OP_END) return NULL;
    else if (c > OP_BRA)
      {
      int n = c - OP_BRA;
      if (n > EXTRACT_BASIC_MAX) n = GET2(code, 2+LINK_SIZE);
      if (n == number) return (uschar *)code;
      code += OP_lengths[OP_BRA];
      }
    else
      {
      code += OP_lengths[c];


#ifdef SUPPORT_UTF8

      /* In UTF-8 mode, opcodes that are followed by a character may be followed
      by a multi-byte character. The length in the table is a minimum, so we have
      to scan along to skip the extra bytes. All opcodes are less than 128, so we
      can use relatively efficient code. */


      if (utf8) switch(c)
        {
        case OP_CHAR:
        case OP_CHARNC:
        case OP_EXACT:
        case OP_UPTO:
        case OP_MINUPTO:
        case OP_STAR:
        case OP_MINSTAR:
        case OP_PLUS:
        case OP_MINPLUS:
        case OP_QUERY:
        case OP_MINQUERY:
        while ((*code & 0xc0) == 0x80) code++;
        break;


        /* XCLASS is used for classes that cannot be represented just by a bit
        map. This includes negated single high-valued characters. The length in
        the table is zero; the actual length is stored in the compiled code. */


        case OP_XCLASS:
        code += GET(code, 1) + 1;
        break;
        }
  #endif
      }
    }
  }




/*************************************************
* Scan compiled regex for recursion reference *
*************************************************/

/* This little function scans through a compiled pattern until it finds an
instance of OP_RECURSE.

  Arguments:
    code        points to start of expression
    utf8        TRUE in UTF-8 mode


  Returns:      pointer to the opcode for OP_RECURSE, or NULL if not found
  */


  static const uschar *
  find_recurse(const uschar *code, BOOL utf8)
  {
  #ifndef SUPPORT_UTF8
  utf8 = utf8;               /* Stop pedantic compilers complaining */
  #endif


  for (;;)
    {
    register int c = *code;
    if (c == OP_END) return NULL;
    else if (c == OP_RECURSE) return code;
    else if (c > OP_BRA)
      {
      code += OP_lengths[OP_BRA];
      }
    else
      {
      code += OP_lengths[c];


#ifdef SUPPORT_UTF8

      /* In UTF-8 mode, opcodes that are followed by a character may be followed
      by a multi-byte character. The length in the table is a minimum, so we have
      to scan along to skip the extra bytes. All opcodes are less than 128, so we
      can use relatively efficient code. */


      if (utf8) switch(c)
        {
        case OP_CHAR:
        case OP_CHARNC:
        case OP_EXACT:
        case OP_UPTO:
        case OP_MINUPTO:
        case OP_STAR:
        case OP_MINSTAR:
        case OP_PLUS:
        case OP_MINPLUS:
        case OP_QUERY:
        case OP_MINQUERY:
        while ((*code & 0xc0) == 0x80) code++;
        break;


        /* XCLASS is used for classes that cannot be represented just by a bit
        map. This includes negated single high-valued characters. The length in
        the table is zero; the actual length is stored in the compiled code. */


        case OP_XCLASS:
        code += GET(code, 1) + 1;
        break;
        }
  #endif
      }
    }
  }




  /*************************************************
  *    Scan compiled branch for non-emptiness      *
  *************************************************/


/* This function scans through a branch of a compiled pattern to see whether it
can match the empty string or not. It is called only from could_be_empty()
below. Note that first_significant_code() skips over assertions. If we hit an
unclosed bracket, we return "empty" - this means we've struck an inner bracket
whose current branch will already have been scanned.

  Arguments:
    code        points to start of search
    endcode     points to where to stop
    utf8        TRUE if in UTF8 mode


  Returns:      TRUE if what is matched could be empty
  */


  static BOOL
  could_be_empty_branch(const uschar *code, const uschar *endcode, BOOL utf8)
  {
  register int c;
  for (code = first_significant_code(code + 1 + LINK_SIZE, NULL, 0, TRUE);
       code < endcode;
       code = first_significant_code(code + OP_lengths[c], NULL, 0, TRUE))
    {
    const uschar *ccode;


    c = *code;


    if (c >= OP_BRA)
      {
      BOOL empty_branch;
      if (GET(code, 1) == 0) return TRUE;    /* Hit unclosed bracket */


      /* Scan a closed bracket */


      empty_branch = FALSE;
      do
        {
        if (!empty_branch && could_be_empty_branch(code, endcode, utf8))
          empty_branch = TRUE;
        code += GET(code, 1);
        }
      while (*code == OP_ALT);
      if (!empty_branch) return FALSE;   /* All branches are non-empty */
      code += 1 + LINK_SIZE;
      c = *code;
      }


    else switch (c)
      {
      /* Check for quantifiers after a class */


  #ifdef SUPPORT_UTF8
      case OP_XCLASS:
      ccode = code + GET(code, 1);
      goto CHECK_CLASS_REPEAT;
  #endif


      case OP_CLASS:
      case OP_NCLASS:
      ccode = code + 33;


  #ifdef SUPPORT_UTF8
      CHECK_CLASS_REPEAT:
  #endif


      switch (*ccode)
        {
        case OP_CRSTAR:            /* These could be empty; continue */
        case OP_CRMINSTAR:
        case OP_CRQUERY:
        case OP_CRMINQUERY:
        break;


        default:                   /* Non-repeat => class must match */
        case OP_CRPLUS:            /* These repeats aren't empty */
        case OP_CRMINPLUS:
        return FALSE;


        case OP_CRRANGE:
        case OP_CRMINRANGE:
        if (GET2(ccode, 1) > 0) return FALSE;  /* Minimum > 0 */
        break;
        }
      break;


      /* Opcodes that must match a character */


      case OP_PROP:
      case OP_NOTPROP:
      case OP_EXTUNI:
      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_ANYBYTE:
      case OP_CHAR:
      case OP_CHARNC:
      case OP_NOT:
      case OP_PLUS:
      case OP_MINPLUS:
      case OP_EXACT:
      case OP_NOTPLUS:
      case OP_NOTMINPLUS:
      case OP_NOTEXACT:
      case OP_TYPEPLUS:
      case OP_TYPEMINPLUS:
      case OP_TYPEEXACT:
      return FALSE;


      /* End of branch */


      case OP_KET:
      case OP_KETRMAX:
      case OP_KETRMIN:
      case OP_ALT:
      return TRUE;


      /* In UTF-8 mode, STAR, MINSTAR, QUERY, MINQUERY, UPTO, and MINUPTO  may be
      followed by a multibyte character */


  #ifdef SUPPORT_UTF8
      case OP_STAR:
      case OP_MINSTAR:
      case OP_QUERY:
      case OP_MINQUERY:
      case OP_UPTO:
      case OP_MINUPTO:
      if (utf8) while ((code[2] & 0xc0) == 0x80) code++;
      break;
  #endif
      }
    }


return TRUE;
}



  /*************************************************
  *    Scan compiled regex for non-emptiness       *
  *************************************************/


/* This function is called to check for left recursive calls. We want to check
the current branch of the current pattern to see if it could match the empty
string. If it could, we must look outwards for branches at other levels,
stopping when we pass beyond the bracket which is the subject of the recursion.

  Arguments:
    code        points to start of the recursion
    endcode     points to where to stop (current RECURSE item)
    bcptr       points to the chain of current (unclosed) branch starts
    utf8        TRUE if in UTF-8 mode


  Returns:      TRUE if what is matched could be empty
  */


  static BOOL
  could_be_empty(const uschar *code, const uschar *endcode, branch_chain *bcptr,
    BOOL utf8)
  {
  while (bcptr != NULL && bcptr->current >= code)
    {
    if (!could_be_empty_branch(bcptr->current, endcode, utf8)) return FALSE;
    bcptr = bcptr->outer;
    }
  return TRUE;
  }




  /*************************************************
  *           Check for POSIX class syntax         *
  *************************************************/


/* This function is called when the sequence "[:" or "[." or "[=" is
encountered in a character class. It checks whether this is followed by an
optional ^ and then a sequence of letters, terminated by a matching ":]" or
".]" or "=]".

  Argument:
    ptr      pointer to the initial [
    endptr   where to return the end pointer
    cd       pointer to compile data


Returns: TRUE or FALSE
*/

  static BOOL
  check_posix_syntax(const uschar *ptr, const uschar **endptr, compile_data *cd)
  {
  int terminator;          /* Don't combine these lines; the Solaris cc */
  terminator = *(++ptr);   /* compiler warns about "non-constant" initializer. */
  if (*(++ptr) == '^') ptr++;
  while ((cd->ctypes[*ptr] & ctype_letter) != 0) ptr++;
  if (*ptr == terminator && ptr[1] == ']')
    {
    *endptr = ptr;
    return TRUE;
    }
  return FALSE;
  }





  /*************************************************
  *          Check POSIX class name                *
  *************************************************/


/* This function is called to check the name given in a POSIX-style class entry
such as [:alnum:].

  Arguments:
    ptr        points to the first letter
    len        the length of the name


  Returns:     a value representing the name, or -1 if unknown
  */


  static int
  check_posix_name(const uschar *ptr, int len)
  {
  register int yield = 0;
  while (posix_name_lengths[yield] != 0)
    {
    if (len == posix_name_lengths[yield] &&
      strncmp((const char *)ptr, posix_names[yield], len) == 0) return yield;
    yield++;
    }
  return -1;
  }



  /*************************************************
  *    Adjust OP_RECURSE items in repeated group   *
  *************************************************/


/* OP_RECURSE items contain an offset from the start of the regex to the group
that is referenced. This means that groups can be replicated for fixed
repetition simply by copying (because the recursion is allowed to refer to
earlier groups that are outside the current group). However, when a group is
optional (i.e. the minimum quantifier is zero), OP_BRAZERO is inserted before
it, after it has been compiled. This means that any OP_RECURSE items within it
that refer to the group itself or any contained groups have to have their
offsets adjusted. That is the job of this function. Before it is called, the
partially compiled regex must be temporarily terminated with OP_END.

  Arguments:
    group      points to the start of the group
    adjust     the amount by which the group is to be moved
    utf8       TRUE in UTF-8 mode
    cd         contains pointers to tables etc.


  Returns:     nothing
  */


  static void
  adjust_recurse(uschar *group, int adjust, BOOL utf8, compile_data *cd)
  {
  uschar *ptr = group;
  while ((ptr = (uschar *)find_recurse(ptr, utf8)) != NULL)
    {
    int offset = GET(ptr, 1);
    if (cd->start_code + offset >= group) PUT(ptr, 1, offset + adjust);
    ptr += 1 + LINK_SIZE;
    }
  }




  /*************************************************
  *        Insert an automatic callout point       *
  *************************************************/


/* This function is called when the PCRE_AUTO_CALLOUT option is set, to insert
callout points before each pattern item.

  Arguments:
    code           current code pointer
    ptr            current pattern pointer
    cd             pointers to tables etc


  Returns:         new code pointer
  */


  static uschar *
  auto_callout(uschar *code, const uschar *ptr, compile_data *cd)
  {
  *code++ = OP_CALLOUT;
  *code++ = 255;
  PUT(code, 0, ptr - cd->start_pattern);  /* Pattern offset */
  PUT(code, LINK_SIZE, 0);                /* Default length */
  return code + 2*LINK_SIZE;
  }




  /*************************************************
  *         Complete a callout item                *
  *************************************************/


/* A callout item contains the length of the next item in the pattern, which
we can't fill in till after we have reached the relevant point. This is used
for both automatic and manual callouts.

  Arguments:
    previous_callout   points to previous callout item
    ptr                current pattern pointer
    cd                 pointers to tables etc


  Returns:             nothing
  */


static void
complete_callout(uschar *previous_callout, const uschar *ptr, compile_data *cd)
{
int length = ptr - cd->start_pattern - GET(previous_callout, 2);
PUT(previous_callout, 2 + LINK_SIZE, length);
}



  #ifdef SUPPORT_UCP
  /*************************************************
  *           Get othercase range                  *
  *************************************************/


/* This function is passed the start and end of a class range, in UTF-8 mode
with UCP support. It searches up the characters, looking for internal ranges of
characters in the "other" case. Each call returns the next one, updating the
start address.

  Arguments:
    cptr        points to starting character value; updated
    d           end value
    ocptr       where to put start of othercase range
    odptr       where to put end of othercase range


  Yield:        TRUE when range returned; FALSE when no more
  */


static BOOL
get_othercase_range(int *cptr, int d, int *ocptr, int *odptr)
{
int c, chartype, othercase, next;

  for (c = *cptr; c <= d; c++)
    {
    if (ucp_findchar(c, &chartype, &othercase) == ucp_L && othercase != 0) break;
    }


if (c > d) return FALSE;

*ocptr = othercase;
next = othercase + 1;

  for (++c; c <= d; c++)
    {
    if (ucp_findchar(c, &chartype, &othercase) != ucp_L || othercase != next)
      break;
    next++;
    }


*odptr = next - 1;
*cptr = c;

return TRUE;
}
#endif /* SUPPORT_UCP */


  /*************************************************
  *           Compile one branch                   *
  *************************************************/


/* Scan the pattern, compiling it into the code vector. If the options are
changed during the branch, the pointer is used to change the external options
bits.

  Arguments:
    optionsptr     pointer to the option bits
    brackets       points to number of extracting brackets used
    codeptr        points to the pointer to the current code point
    ptrptr         points to the current pattern pointer
    errorptr       points to pointer to error message
    firstbyteptr   set to initial literal character, or < 0 (REQ_UNSET, REQ_NONE)
    reqbyteptr     set to the last literal character required, else < 0
    bcptr          points to current branch chain
    cd             contains pointers to tables etc.


  Returns:         TRUE on success
                   FALSE, with *errorptr set on error
  */


  static BOOL
  compile_branch(int *optionsptr, int *brackets, uschar **codeptr,
    const uschar **ptrptr, const char **errorptr, int *firstbyteptr,
    int *reqbyteptr, branch_chain *bcptr, compile_data *cd)
  {
  int repeat_type, op_type;
  int repeat_min = 0, repeat_max = 0;      /* To please picky compilers */
  int bravalue = 0;
  int greedy_default, greedy_non_default;
  int firstbyte, reqbyte;
  int zeroreqbyte, zerofirstbyte;
  int req_caseopt, reqvary, tempreqvary;
  int condcount = 0;
  int options = *optionsptr;
  int after_manual_callout = 0;
  register int c;
  register uschar *code = *codeptr;
  uschar *tempcode;
  BOOL inescq = FALSE;
  BOOL groupsetfirstbyte = FALSE;
  const uschar *ptr = *ptrptr;
  const uschar *tempptr;
  uschar *previous = NULL;
  uschar *previous_callout = NULL;
  uschar classbits[32];


#ifdef SUPPORT_UTF8
BOOL class_utf8;
BOOL utf8 = (options & PCRE_UTF8) != 0;
uschar *class_utf8data;
uschar utf8_char[6];
#else
BOOL utf8 = FALSE;
#endif

/* Set up the default and non-default settings for greediness */

greedy_default = ((options & PCRE_UNGREEDY) != 0);
greedy_non_default = greedy_default ^ 1;

/* Initialize no first byte, no required byte. REQ_UNSET means "no char
matching encountered yet". It gets changed to REQ_NONE if we hit something that
matches a non-fixed char first char; reqbyte just remains unset if we never
find one.

When we hit a repeat whose minimum is zero, we may have to adjust these values
to take the zero repeat into account. This is implemented by setting them to
zerofirstbyte and zeroreqbyte when such a repeat is encountered. The individual
item types that can be repeated set these backoff variables appropriately. */

firstbyte = reqbyte = zerofirstbyte = zeroreqbyte = REQ_UNSET;

/* The variable req_caseopt contains either the REQ_CASELESS value or zero,
according to the current setting of the caseless flag. REQ_CASELESS is a bit
value > 255. It is added into the firstbyte or reqbyte variables to record the
case status of the value. This is used only for ASCII characters. */

req_caseopt = ((options & PCRE_CASELESS) != 0)? REQ_CASELESS : 0;

/* Switch on next character until the end of the branch */

  for (;; ptr++)
    {
    BOOL negate_class;
    BOOL possessive_quantifier;
    BOOL is_quantifier;
    int class_charcount;
    int class_lastchar;
    int newoptions;
    int recno;
    int skipbytes;
    int subreqbyte;
    int subfirstbyte;
    int mclength;
    uschar mcbuffer[8];


    /* Next byte in the pattern */


    c = *ptr;


    /* If in \Q...\E, check for the end; if not, we have a literal */


    if (inescq && c != 0)
      {
      if (c == '\\' && ptr[1] == 'E')
        {
        inescq = FALSE;
        ptr++;
        continue;
        }
      else
        {
        if (previous_callout != NULL)
          {
          complete_callout(previous_callout, ptr, cd);
          previous_callout = NULL;
          }
        if ((options & PCRE_AUTO_CALLOUT) != 0)
          {
          previous_callout = code;
          code = auto_callout(code, ptr, cd);
          }
        goto NORMAL_CHAR;
        }
      }


    /* Fill in length of a previous callout, except when the next thing is
    a quantifier. */


    is_quantifier = c == '*' || c == '+' || c == '?' ||
      (c == '{' && is_counted_repeat(ptr+1));


    if (!is_quantifier && previous_callout != NULL &&
         after_manual_callout-- <= 0)
      {
      complete_callout(previous_callout, ptr, cd);
      previous_callout = NULL;
      }


    /* In extended mode, skip white space and comments */


    if ((options & PCRE_EXTENDED) != 0)
      {
      if ((cd->ctypes[c] & ctype_space) != 0) continue;
      if (c == '#')
        {
        /* The space before the ; is to avoid a warning on a silly compiler
        on the Macintosh. */
        while ((c = *(++ptr)) != 0 && c != NEWLINE) ;
        if (c != 0) continue;   /* Else fall through to handle end of string */
        }
      }


    /* No auto callout for quantifiers. */


    if ((options & PCRE_AUTO_CALLOUT) != 0 && !is_quantifier)
      {
      previous_callout = code;
      code = auto_callout(code, ptr, cd);
      }


    switch(c)
      {
      /* The branch terminates at end of string, |, or ). */


      case 0:
      case '|':
      case ')':
      *firstbyteptr = firstbyte;
      *reqbyteptr = reqbyte;
      *codeptr = code;
      *ptrptr = ptr;
      return TRUE;


      /* Handle single-character metacharacters. In multiline mode, ^ disables
      the setting of any following char as a first character. */


      case '^':
      if ((options & PCRE_MULTILINE) != 0)
        {
        if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
        }
      previous = NULL;
      *code++ = OP_CIRC;
      break;


      case '$':
      previous = NULL;
      *code++ = OP_DOLL;
      break;


      /* There can never be a first char if '.' is first, whatever happens about
      repeats. The value of reqbyte doesn't change either. */


      case '.':
      if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
      zerofirstbyte = firstbyte;
      zeroreqbyte = reqbyte;
      previous = code;
      *code++ = OP_ANY;
      break;


      /* Character classes. If the included characters are all < 255 in value, we
      build a 32-byte bitmap of the permitted characters, except in the special
      case where there is only one such character. For negated classes, we build
      the map as usual, then invert it at the end. However, we use a different
      opcode so that data characters > 255 can be handled correctly.


      If the class contains characters outside the 0-255 range, a different
      opcode is compiled. It may optionally have a bit map for characters < 256,
      but those above are are explicitly listed afterwards. A flag byte tells
      whether the bitmap is present, and whether this is a negated class or not.
      */


      case '[':
      previous = code;


      /* PCRE supports POSIX class stuff inside a class. Perl gives an error if
      they are encountered at the top level, so we'll do that too. */


      if ((ptr[1] == ':' || ptr[1] == '.' || ptr[1] == '=') &&
          check_posix_syntax(ptr, &tempptr, cd))
        {
        *errorptr = (ptr[1] == ':')? ERR13 : ERR31;
        goto FAILED;
        }


      /* If the first character is '^', set the negation flag and skip it. */


      if ((c = *(++ptr)) == '^')
        {
        negate_class = TRUE;
        c = *(++ptr);
        }
      else
        {
        negate_class = FALSE;
        }


      /* Keep a count of chars with values < 256 so that we can optimize the case
      of just a single character (as long as it's < 256). For higher valued UTF-8
      characters, we don't yet do any optimization. */


      class_charcount = 0;
      class_lastchar = -1;


  #ifdef SUPPORT_UTF8
      class_utf8 = FALSE;                       /* No chars >= 256 */
      class_utf8data = code + LINK_SIZE + 34;   /* For UTF-8 items */
  #endif


      /* Initialize the 32-char bit map to all zeros. We have to build the
      map in a temporary bit of store, in case the class contains only 1
      character (< 256), because in that case the compiled code doesn't use the
      bit map. */


      memset(classbits, 0, 32 * sizeof(uschar));


      /* Process characters until ] is reached. By writing this as a "do" it
      means that an initial ] is taken as a data character. The first pass
      through the regex checked the overall syntax, so we don't need to be very
      strict here. At the start of the loop, c contains the first byte of the
      character. */


      do
        {
  #ifdef SUPPORT_UTF8
        if (utf8 && c > 127)
          {                           /* Braces are required because the */
          GETCHARLEN(c, ptr, ptr);    /* macro generates multiple statements */
          }
  #endif


        /* Inside \Q...\E everything is literal except \E */


        if (inescq)
          {
          if (c == '\\' && ptr[1] == 'E')
            {
            inescq = FALSE;
            ptr++;
            continue;
            }
          else goto LONE_SINGLE_CHARACTER;
          }


        /* Handle POSIX class names. Perl allows a negation extension of the
        form [:^name:]. A square bracket that doesn't match the syntax is
        treated as a literal. We also recognize the POSIX constructions
        [.ch.] and [=ch=] ("collating elements") and fault them, as Perl
        5.6 and 5.8 do. */


        if (c == '[' &&
            (ptr[1] == ':' || ptr[1] == '.' || ptr[1] == '=') &&
            check_posix_syntax(ptr, &tempptr, cd))
          {
          BOOL local_negate = FALSE;
          int posix_class, i;
          register const uschar *cbits = cd->cbits;


          if (ptr[1] != ':')
            {
            *errorptr = ERR31;
            goto FAILED;
            }


          ptr += 2;
          if (*ptr == '^')
            {
            local_negate = TRUE;
            ptr++;
            }


          posix_class = check_posix_name(ptr, tempptr - ptr);
          if (posix_class < 0)
            {
            *errorptr = ERR30;
            goto FAILED;
            }


          /* If matching is caseless, upper and lower are converted to
          alpha. This relies on the fact that the class table starts with
          alpha, lower, upper as the first 3 entries. */


          if ((options & PCRE_CASELESS) != 0 && posix_class <= 2)
            posix_class = 0;


          /* Or into the map we are building up to 3 of the static class
          tables, or their negations. The [:blank:] class sets up the same
          chars as the [:space:] class (all white space). We remove the vertical
          white space chars afterwards. */


          posix_class *= 3;
          for (i = 0; i < 3; i++)
            {
            BOOL blankclass = strncmp((char *)ptr, "blank", 5) == 0;
            int taboffset = posix_class_maps[posix_class + i];
            if (taboffset < 0) break;
            if (local_negate)
              {
              if (i == 0)
                for (c = 0; c < 32; c++) classbits[c] |= ~cbits[c+taboffset];
              else
                for (c = 0; c < 32; c++) classbits[c] &= ~cbits[c+taboffset];
              if (blankclass) classbits[1] |= 0x3c;
              }
            else
              {
              for (c = 0; c < 32; c++) classbits[c] |= cbits[c+taboffset];
              if (blankclass) classbits[1] &= ~0x3c;
              }
            }


          ptr = tempptr + 1;
          class_charcount = 10;  /* Set > 1; assumes more than 1 per class */
          continue;    /* End of POSIX syntax handling */
          }


        /* Backslash may introduce a single character, or it may introduce one
        of the specials, which just set a flag. Escaped items are checked for
        validity in the pre-compiling pass. The sequence \b is a special case.
        Inside a class (and only there) it is treated as backspace. Elsewhere
        it marks a word boundary. Other escapes have preset maps ready to
        or into the one we are building. We assume they have more than one
        character in them, so set class_charcount bigger than one. */


        if (c == '\\')
          {
          c = check_escape(&ptr, errorptr, *brackets, options, TRUE);


          if (-c == ESC_b) c = '\b';       /* \b is backslash in a class */
          else if (-c == ESC_X) c = 'X';   /* \X is literal X in a class */
          else if (-c == ESC_Q)            /* Handle start of quoted string */
            {
            if (ptr[1] == '\\' && ptr[2] == 'E')
              {
              ptr += 2; /* avoid empty string */
              }
            else inescq = TRUE;
            continue;
            }


          if (c < 0)
            {
            register const uschar *cbits = cd->cbits;
            class_charcount += 2;     /* Greater than 1 is what matters */
            switch (-c)
              {
              case ESC_d:
              for (c = 0; c < 32; c++) classbits[c] |= cbits[c+cbit_digit];
              continue;


              case ESC_D:
              for (c = 0; c < 32; c++) classbits[c] |= ~cbits[c+cbit_digit];
              continue;


              case ESC_w:
              for (c = 0; c < 32; c++) classbits[c] |= cbits[c+cbit_word];
              continue;


              case ESC_W:
              for (c = 0; c < 32; c++) classbits[c] |= ~cbits[c+cbit_word];
              continue;


              case ESC_s:
              for (c = 0; c < 32; c++) classbits[c] |= cbits[c+cbit_space];
              classbits[1] &= ~0x08;   /* Perl 5.004 onwards omits VT from \s */
              continue;


              case ESC_S:
              for (c = 0; c < 32; c++) classbits[c] |= ~cbits[c+cbit_space];
              classbits[1] |= 0x08;    /* Perl 5.004 onwards omits VT from \s */
              continue;


  #ifdef SUPPORT_UCP
              case ESC_p:
              case ESC_P:
                {
                BOOL negated;
                int property = get_ucp(&ptr, &negated, errorptr);
                if (property < 0) goto FAILED;
                class_utf8 = TRUE;
                *class_utf8data++ = ((-c == ESC_p) != negated)?
                  XCL_PROP : XCL_NOTPROP;
                *class_utf8data++ = property;
                class_charcount -= 2;   /* Not a < 256 character */
                }
              continue;
  #endif


              /* Unrecognized escapes are faulted if PCRE is running in its
              strict mode. By default, for compatibility with Perl, they are
              treated as literals. */


              default:
              if ((options & PCRE_EXTRA) != 0)
                {
                *errorptr = ERR7;
                goto FAILED;
                }
              c = *ptr;              /* The final character */
              class_charcount -= 2;  /* Undo the default count from above */
              }
            }


          /* Fall through if we have a single character (c >= 0). This may be
          > 256 in UTF-8 mode. */


          }   /* End of backslash handling */


        /* A single character may be followed by '-' to form a range. However,
        Perl does not permit ']' to be the end of the range. A '-' character
        here is treated as a literal. */


        if (ptr[1] == '-' && ptr[2] != ']')
          {
          int d;
          ptr += 2;


  #ifdef SUPPORT_UTF8
          if (utf8)
            {                           /* Braces are required because the */
            GETCHARLEN(d, ptr, ptr);    /* macro generates multiple statements */
            }
          else
  #endif
          d = *ptr;  /* Not UTF-8 mode */


          /* The second part of a range can be a single-character escape, but
          not any of the other escapes. Perl 5.6 treats a hyphen as a literal
          in such circumstances. */


          if (d == '\\')
            {
            const uschar *oldptr = ptr;
            d = check_escape(&ptr, errorptr, *brackets, options, TRUE);


            /* \b is backslash; \X is literal X; any other special means the '-'
            was literal */


            if (d < 0)
              {
              if (d == -ESC_b) d = '\b';
              else if (d == -ESC_X) d = 'X'; else
                {
                ptr = oldptr - 2;
                goto LONE_SINGLE_CHARACTER;  /* A few lines below */
                }
              }
            }


          /* The check that the two values are in the correct order happens in
          the pre-pass. Optimize one-character ranges */


          if (d == c) goto LONE_SINGLE_CHARACTER;  /* A few lines below */


          /* In UTF-8 mode, if the upper limit is > 255, or > 127 for caseless
          matching, we have to use an XCLASS with extra data items. Caseless
          matching for characters > 127 is available only if UCP support is
          available. */


  #ifdef SUPPORT_UTF8
          if (utf8 && (d > 255 || ((options & PCRE_CASELESS) != 0 && d > 127)))
            {
            class_utf8 = TRUE;


            /* With UCP support, we can find the other case equivalents of
            the relevant characters. There may be several ranges. Optimize how
            they fit with the basic range. */


  #ifdef SUPPORT_UCP
            if ((options & PCRE_CASELESS) != 0)
              {
              int occ, ocd;
              int cc = c;
              int origd = d;
              while (get_othercase_range(&cc, origd, &occ, &ocd))
                {
                if (occ >= c && ocd <= d) continue;  /* Skip embedded ranges */


                if (occ < c  && ocd >= c - 1)        /* Extend the basic range */
                  {                                  /* if there is overlap,   */
                  c = occ;                           /* noting that if occ < c */
                  continue;                          /* we can't have ocd > d  */
                  }                                  /* because a subrange is  */
                if (ocd > d && occ <= d + 1)         /* always shorter than    */
                  {                                  /* the basic range.       */
                  d = ocd;
                  continue;
                  }


                if (occ == ocd)
                  {
                  *class_utf8data++ = XCL_SINGLE;
                  }
                else
                  {
                  *class_utf8data++ = XCL_RANGE;
                  class_utf8data += ord2utf8(occ, class_utf8data);
                  }
                class_utf8data += ord2utf8(ocd, class_utf8data);
                }
              }
  #endif  /* SUPPORT_UCP */


            /* Now record the original range, possibly modified for UCP caseless
            overlapping ranges. */


            *class_utf8data++ = XCL_RANGE;
            class_utf8data += ord2utf8(c, class_utf8data);
            class_utf8data += ord2utf8(d, class_utf8data);


            /* With UCP support, we are done. Without UCP support, there is no
            caseless matching for UTF-8 characters > 127; we can use the bit map
            for the smaller ones. */


  #ifdef SUPPORT_UCP
            continue;    /* With next character in the class */
  #else
            if ((options & PCRE_CASELESS) == 0 || c > 127) continue;


            /* Adjust upper limit and fall through to set up the map */


            d = 127;


  #endif  /* SUPPORT_UCP */
            }
  #endif  /* SUPPORT_UTF8 */


          /* We use the bit map for all cases when not in UTF-8 mode; else
          ranges that lie entirely within 0-127 when there is UCP support; else
          for partial ranges without UCP support. */


          for (; c <= d; c++)
            {
            classbits[c/8] |= (1 << (c&7));
            if ((options & PCRE_CASELESS) != 0)
              {
              int uc = cd->fcc[c];           /* flip case */
              classbits[uc/8] |= (1 << (uc&7));
              }
            class_charcount++;                /* in case a one-char range */
            class_lastchar = c;
            }


          continue;   /* Go get the next char in the class */
          }


        /* Handle a lone single character - we can get here for a normal
        non-escape char, or after \ that introduces a single character or for an
        apparent range that isn't. */


        LONE_SINGLE_CHARACTER:


        /* Handle a character that cannot go in the bit map */


  #ifdef SUPPORT_UTF8
        if (utf8 && (c > 255 || ((options & PCRE_CASELESS) != 0 && c > 127)))
          {
          class_utf8 = TRUE;
          *class_utf8data++ = XCL_SINGLE;
          class_utf8data += ord2utf8(c, class_utf8data);


  #ifdef SUPPORT_UCP
          if ((options & PCRE_CASELESS) != 0)
            {
            int chartype;
            int othercase;
            if (ucp_findchar(c, &chartype, &othercase) >= 0 && othercase > 0)
              {
              *class_utf8data++ = XCL_SINGLE;
              class_utf8data += ord2utf8(othercase, class_utf8data);
              }
            }
  #endif  /* SUPPORT_UCP */


          }
        else
  #endif  /* SUPPORT_UTF8 */


        /* Handle a single-byte character */
          {
          classbits[c/8] |= (1 << (c&7));
          if ((options & PCRE_CASELESS) != 0)
            {
            c = cd->fcc[c];   /* flip case */
            classbits[c/8] |= (1 << (c&7));
            }
          class_charcount++;
          class_lastchar = c;
          }
        }


      /* Loop until ']' reached; the check for end of string happens inside the
      loop. This "while" is the end of the "do" above. */


      while ((c = *(++ptr)) != ']' || inescq);


      /* If class_charcount is 1, we saw precisely one character whose value is
      less than 256. In non-UTF-8 mode we can always optimize. In UTF-8 mode, we
      can optimize the negative case only if there were no characters >= 128
      because OP_NOT and the related opcodes like OP_NOTSTAR operate on
      single-bytes only. This is an historical hangover. Maybe one day we can
      tidy these opcodes to handle multi-byte characters.


      The optimization throws away the bit map. We turn the item into a
      1-character OP_CHAR[NC] if it's positive, or OP_NOT if it's negative. Note
      that OP_NOT does not support multibyte characters. In the positive case, it
      can cause firstbyte to be set. Otherwise, there can be no first char if
      this item is first, whatever repeat count may follow. In the case of
      reqbyte, save the previous value for reinstating. */


  #ifdef SUPPORT_UTF8
      if (class_charcount == 1 &&
            (!utf8 ||
            (!class_utf8 && (!negate_class || class_lastchar < 128))))


  #else
      if (class_charcount == 1)
  #endif
        {
        zeroreqbyte = reqbyte;


        /* The OP_NOT opcode works on one-byte characters only. */


        if (negate_class)
          {
          if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
          zerofirstbyte = firstbyte;
          *code++ = OP_NOT;
          *code++ = class_lastchar;
          break;
          }


        /* For a single, positive character, get the value into mcbuffer, and
        then we can handle this with the normal one-character code. */


  #ifdef SUPPORT_UTF8
        if (utf8 && class_lastchar > 127)
          mclength = ord2utf8(class_lastchar, mcbuffer);
        else
  #endif
          {
          mcbuffer[0] = class_lastchar;
          mclength = 1;
          }
        goto ONE_CHAR;
        }       /* End of 1-char optimization */


      /* The general case - not the one-char optimization. If this is the first
      thing in the branch, there can be no first char setting, whatever the
      repeat count. Any reqbyte setting must remain unchanged after any kind of
      repeat. */


      if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
      zerofirstbyte = firstbyte;
      zeroreqbyte = reqbyte;


      /* If there are characters with values > 255, we have to compile an
      extended class, with its own opcode. If there are no characters < 256,
      we can omit the bitmap. */


  #ifdef SUPPORT_UTF8
      if (class_utf8)
        {
        *class_utf8data++ = XCL_END;    /* Marks the end of extra data */
        *code++ = OP_XCLASS;
        code += LINK_SIZE;
        *code = negate_class? XCL_NOT : 0;


        /* If the map is required, install it, and move on to the end of
        the extra data */


        if (class_charcount > 0)
          {
          *code++ |= XCL_MAP;
          memcpy(code, classbits, 32);
          code = class_utf8data;
          }


        /* If the map is not required, slide down the extra data. */


        else
          {
          int len = class_utf8data - (code + 33);
          memmove(code + 1, code + 33, len);
          code += len + 1;
          }


        /* Now fill in the complete length of the item */


        PUT(previous, 1, code - previous);
        break;   /* End of class handling */
        }
  #endif


      /* If there are no characters > 255, negate the 32-byte map if necessary,
      and copy it into the code vector. If this is the first thing in the branch,
      there can be no first char setting, whatever the repeat count. Any reqbyte
      setting must remain unchanged after any kind of repeat. */


      if (negate_class)
        {
        *code++ = OP_NCLASS;
        for (c = 0; c < 32; c++) code[c] = ~classbits[c];
        }
      else
        {
        *code++ = OP_CLASS;
        memcpy(code, classbits, 32);
        }
      code += 32;
      break;


      /* Various kinds of repeat; '{' is not necessarily a quantifier, but this
      has been tested above. */


      case '{':
      if (!is_quantifier) goto NORMAL_CHAR;
      ptr = read_repeat_counts(ptr+1, &repeat_min, &repeat_max, errorptr);
      if (*errorptr != NULL) goto FAILED;
      goto REPEAT;


      case '*':
      repeat_min = 0;
      repeat_max = -1;
      goto REPEAT;


      case '+':
      repeat_min = 1;
      repeat_max = -1;
      goto REPEAT;


      case '?':
      repeat_min = 0;
      repeat_max = 1;


      REPEAT:
      if (previous == NULL)
        {
        *errorptr = ERR9;
        goto FAILED;
        }


      if (repeat_min == 0)
        {
        firstbyte = zerofirstbyte;    /* Adjust for zero repeat */
        reqbyte = zeroreqbyte;        /* Ditto */
        }


      /* Remember whether this is a variable length repeat */


      reqvary = (repeat_min == repeat_max)? 0 : REQ_VARY;


      op_type = 0;                    /* Default single-char op codes */
      possessive_quantifier = FALSE;  /* Default not possessive quantifier */


      /* Save start of previous item, in case we have to move it up to make space
      for an inserted OP_ONCE for the additional '+' extension. */


      tempcode = previous;


      /* If the next character is '+', we have a possessive quantifier. This
      implies greediness, whatever the setting of the PCRE_UNGREEDY option.
      If the next character is '?' this is a minimizing repeat, by default,
      but if PCRE_UNGREEDY is set, it works the other way round. We change the
      repeat type to the non-default. */


      if (ptr[1] == '+')
        {
        repeat_type = 0;                  /* Force greedy */
        possessive_quantifier = TRUE;
        ptr++;
        }
      else if (ptr[1] == '?')
        {
        repeat_type = greedy_non_default;
        ptr++;
        }
      else repeat_type = greedy_default;


      /* If previous was a recursion, we need to wrap it inside brackets so that
      it can be replicated if necessary. */


      if (*previous == OP_RECURSE)
        {
        memmove(previous + 1 + LINK_SIZE, previous, 1 + LINK_SIZE);
        code += 1 + LINK_SIZE;
        *previous = OP_BRA;
        PUT(previous, 1, code - previous);
        *code = OP_KET;
        PUT(code, 1, code - previous);
        code += 1 + LINK_SIZE;
        }


      /* If previous was a character match, abolish the item and generate a
      repeat item instead. If a char item has a minumum of more than one, ensure
      that it is set in reqbyte - it might not be if a sequence such as x{3} is
      the first thing in a branch because the x will have gone into firstbyte
      instead.  */


      if (*previous == OP_CHAR || *previous == OP_CHARNC)
        {
        /* Deal with UTF-8 characters that take up more than one byte. It's
        easier to write this out separately than try to macrify it. Use c to
        hold the length of the character in bytes, plus 0x80 to flag that it's a
        length rather than a small character. */


  #ifdef SUPPORT_UTF8
        if (utf8 && (code[-1] & 0x80) != 0)
          {
          uschar *lastchar = code - 1;
          while((*lastchar & 0xc0) == 0x80) lastchar--;
          c = code - lastchar;            /* Length of UTF-8 character */
          memcpy(utf8_char, lastchar, c); /* Save the char */
          c |= 0x80;                      /* Flag c as a length */
          }
        else
  #endif


        /* Handle the case of a single byte - either with no UTF8 support, or
        with UTF-8 disabled, or for a UTF-8 character < 128. */


          {
          c = code[-1];
          if (repeat_min > 1) reqbyte = c | req_caseopt | cd->req_varyopt;
          }


        goto OUTPUT_SINGLE_REPEAT;   /* Code shared with single character types */
        }


      /* If previous was a single negated character ([^a] or similar), we use
      one of the special opcodes, replacing it. The code is shared with single-
      character repeats by setting opt_type to add a suitable offset into
      repeat_type. OP_NOT is currently used only for single-byte chars. */


      else if (*previous == OP_NOT)
        {
        op_type = OP_NOTSTAR - OP_STAR;  /* Use "not" opcodes */
        c = previous[1];
        goto OUTPUT_SINGLE_REPEAT;
        }


      /* If previous was a character type match (\d or similar), abolish it and
      create a suitable repeat item. The code is shared with single-character
      repeats by setting op_type to add a suitable offset into repeat_type. Note
      the the Unicode property types will be present only when SUPPORT_UCP is
      defined, but we don't wrap the little bits of code here because it just
      makes it horribly messy. */


      else if (*previous < OP_EODN)
        {
        uschar *oldcode;
        int prop_type;
        op_type = OP_TYPESTAR - OP_STAR;  /* Use type opcodes */
        c = *previous;


        OUTPUT_SINGLE_REPEAT:
        prop_type = (*previous == OP_PROP || *previous == OP_NOTPROP)?
          previous[1] : -1;


        oldcode = code;
        code = previous;                  /* Usually overwrite previous item */


        /* If the maximum is zero then the minimum must also be zero; Perl allows
        this case, so we do too - by simply omitting the item altogether. */


        if (repeat_max == 0) goto END_REPEAT;


        /* All real repeats make it impossible to handle partial matching (maybe
        one day we will be able to remove this restriction). */


        if (repeat_max != 1) cd->nopartial = TRUE;


        /* Combine the op_type with the repeat_type */


        repeat_type += op_type;


        /* A minimum of zero is handled either as the special case * or ?, or as
        an UPTO, with the maximum given. */


        if (repeat_min == 0)
          {
          if (repeat_max == -1) *code++ = OP_STAR + repeat_type;
            else if (repeat_max == 1) *code++ = OP_QUERY + repeat_type;
          else
            {
            *code++ = OP_UPTO + repeat_type;
            PUT2INC(code, 0, repeat_max);
            }
          }


        /* A repeat minimum of 1 is optimized into some special cases. If the
        maximum is unlimited, we use OP_PLUS. Otherwise, the original item it
        left in place and, if the maximum is greater than 1, we use OP_UPTO with
        one less than the maximum. */


        else if (repeat_min == 1)
          {
          if (repeat_max == -1)
            *code++ = OP_PLUS + repeat_type;
          else
            {
            code = oldcode;                 /* leave previous item in place */
            if (repeat_max == 1) goto END_REPEAT;
            *code++ = OP_UPTO + repeat_type;
            PUT2INC(code, 0, repeat_max - 1);
            }
          }


        /* The case {n,n} is just an EXACT, while the general case {n,m} is
        handled as an EXACT followed by an UPTO. */


        else
          {
          *code++ = OP_EXACT + op_type;  /* NB EXACT doesn't have repeat_type */
          PUT2INC(code, 0, repeat_min);


          /* If the maximum is unlimited, insert an OP_STAR. Before doing so,
          we have to insert the character for the previous code. For a repeated
          Unicode property match, there is an extra byte that defines the
          required property. In UTF-8 mode, long characters have their length in
          c, with the 0x80 bit as a flag. */


          if (repeat_max < 0)
            {
  #ifdef SUPPORT_UTF8
            if (utf8 && c >= 128)
              {
              memcpy(code, utf8_char, c & 7);
              code += c & 7;
              }
            else
  #endif
              {
              *code++ = c;
              if (prop_type >= 0) *code++ = prop_type;
              }
            *code++ = OP_STAR + repeat_type;
            }


          /* Else insert an UPTO if the max is greater than the min, again
          preceded by the character, for the previously inserted code. */


          else if (repeat_max != repeat_min)
            {
  #ifdef SUPPORT_UTF8
            if (utf8 && c >= 128)
              {
              memcpy(code, utf8_char, c & 7);
              code += c & 7;
              }
            else
  #endif
            *code++ = c;
            if (prop_type >= 0) *code++ = prop_type;
            repeat_max -= repeat_min;
            *code++ = OP_UPTO + repeat_type;
            PUT2INC(code, 0, repeat_max);
            }
          }


        /* The character or character type itself comes last in all cases. */


  #ifdef SUPPORT_UTF8
        if (utf8 && c >= 128)
          {
          memcpy(code, utf8_char, c & 7);
          code += c & 7;
          }
        else
  #endif
        *code++ = c;


        /* For a repeated Unicode property match, there is an extra byte that
        defines the required property. */


  #ifdef SUPPORT_UCP
        if (prop_type >= 0) *code++ = prop_type;
  #endif
        }


      /* If previous was a character class or a back reference, we put the repeat
      stuff after it, but just skip the item if the repeat was {0,0}. */


      else if (*previous == OP_CLASS ||
               *previous == OP_NCLASS ||
  #ifdef SUPPORT_UTF8
               *previous == OP_XCLASS ||
  #endif
               *previous == OP_REF)
        {
        if (repeat_max == 0)
          {
          code = previous;
          goto END_REPEAT;
          }


        /* All real repeats make it impossible to handle partial matching (maybe
        one day we will be able to remove this restriction). */


        if (repeat_max != 1) cd->nopartial = TRUE;


        if (repeat_min == 0 && repeat_max == -1)
          *code++ = OP_CRSTAR + repeat_type;
        else if (repeat_min == 1 && repeat_max == -1)
          *code++ = OP_CRPLUS + repeat_type;
        else if (repeat_min == 0 && repeat_max == 1)
          *code++ = OP_CRQUERY + repeat_type;
        else
          {
          *code++ = OP_CRRANGE + repeat_type;
          PUT2INC(code, 0, repeat_min);
          if (repeat_max == -1) repeat_max = 0;  /* 2-byte encoding for max */
          PUT2INC(code, 0, repeat_max);
          }
        }


      /* If previous was a bracket group, we may have to replicate it in certain
      cases. */


      else if (*previous >= OP_BRA || *previous == OP_ONCE ||
               *previous == OP_COND)
        {
        register int i;
        int ketoffset = 0;
        int len = code - previous;
        uschar *bralink = NULL;


        /* If the maximum repeat count is unlimited, find the end of the bracket
        by scanning through from the start, and compute the offset back to it
        from the current code pointer. There may be an OP_OPT setting following
        the final KET, so we can't find the end just by going back from the code
        pointer. */


        if (repeat_max == -1)
          {
          register uschar *ket = previous;
          do ket += GET(ket, 1); while (*ket != OP_KET);
          ketoffset = code - ket;
          }


        /* The case of a zero minimum is special because of the need to stick
        OP_BRAZERO in front of it, and because the group appears once in the
        data, whereas in other cases it appears the minimum number of times. For
        this reason, it is simplest to treat this case separately, as otherwise
        the code gets far too messy. There are several special subcases when the
        minimum is zero. */


        if (repeat_min == 0)
          {
          /* If the maximum is also zero, we just omit the group from the output
          altogether. */


          if (repeat_max == 0)
            {
            code = previous;
            goto END_REPEAT;
            }


          /* If the maximum is 1 or unlimited, we just have to stick in the
          BRAZERO and do no more at this point. However, we do need to adjust
          any OP_RECURSE calls inside the group that refer to the group itself or
          any internal group, because the offset is from the start of the whole
          regex. Temporarily terminate the pattern while doing this. */


          if (repeat_max <= 1)
            {
            *code = OP_END;
            adjust_recurse(previous, 1, utf8, cd);
            memmove(previous+1, previous, len);
            code++;
            *previous++ = OP_BRAZERO + repeat_type;
            }


          /* If the maximum is greater than 1 and limited, we have to replicate
          in a nested fashion, sticking OP_BRAZERO before each set of brackets.
          The first one has to be handled carefully because it's the original
          copy, which has to be moved up. The remainder can be handled by code
          that is common with the non-zero minimum case below. We have to
          adjust the value or repeat_max, since one less copy is required. Once
          again, we may have to adjust any OP_RECURSE calls inside the group. */


          else
            {
            int offset;
            *code = OP_END;
            adjust_recurse(previous, 2 + LINK_SIZE, utf8, cd);
            memmove(previous + 2 + LINK_SIZE, previous, len);
            code += 2 + LINK_SIZE;
            *previous++ = OP_BRAZERO + repeat_type;
            *previous++ = OP_BRA;


            /* We chain together the bracket offset fields that have to be
            filled in later when the ends of the brackets are reached. */


            offset = (bralink == NULL)? 0 : previous - bralink;
            bralink = previous;
            PUTINC(previous, 0, offset);
            }


          repeat_max--;
          }


        /* If the minimum is greater than zero, replicate the group as many
        times as necessary, and adjust the maximum to the number of subsequent
        copies that we need. If we set a first char from the group, and didn't
        set a required char, copy the latter from the former. */


        else
          {
          if (repeat_min > 1)
            {
            if (groupsetfirstbyte && reqbyte < 0) reqbyte = firstbyte;
            for (i = 1; i < repeat_min; i++)
              {
              memcpy(code, previous, len);
              code += len;
              }
            }
          if (repeat_max > 0) repeat_max -= repeat_min;
          }


        /* This code is common to both the zero and non-zero minimum cases. If
        the maximum is limited, it replicates the group in a nested fashion,
        remembering the bracket starts on a stack. In the case of a zero minimum,
        the first one was set up above. In all cases the repeat_max now specifies
        the number of additional copies needed. */


        if (repeat_max >= 0)
          {
          for (i = repeat_max - 1; i >= 0; i--)
            {
            *code++ = OP_BRAZERO + repeat_type;


            /* All but the final copy start a new nesting, maintaining the
            chain of brackets outstanding. */


            if (i != 0)
              {
              int offset;
              *code++ = OP_BRA;
              offset = (bralink == NULL)? 0 : code - bralink;
              bralink = code;
              PUTINC(code, 0, offset);
              }


            memcpy(code, previous, len);
            code += len;
            }


          /* Now chain through the pending brackets, and fill in their length
          fields (which are holding the chain links pro tem). */


          while (bralink != NULL)
            {
            int oldlinkoffset;
            int offset = code - bralink + 1;
            uschar *bra = code - offset;
            oldlinkoffset = GET(bra, 1);
            bralink = (oldlinkoffset == 0)? NULL : bralink - oldlinkoffset;
            *code++ = OP_KET;
            PUTINC(code, 0, offset);
            PUT(bra, 1, offset);
            }
          }


        /* If the maximum is unlimited, set a repeater in the final copy. We
        can't just offset backwards from the current code point, because we
        don't know if there's been an options resetting after the ket. The
        correct offset was computed above. */


        else code[-ketoffset] = OP_KETRMAX + repeat_type;
        }


      /* Else there's some kind of shambles */


      else
        {
        *errorptr = ERR11;
        goto FAILED;
        }


      /* If the character following a repeat is '+', we wrap the entire repeated
      item inside OP_ONCE brackets. This is just syntactic sugar, taken from
      Sun's Java package. The repeated item starts at tempcode, not at previous,
      which might be the first part of a string whose (former) last char we
      repeated. However, we don't support '+' after a greediness '?'. */


      if (possessive_quantifier)
        {
        int len = code - tempcode;
        memmove(tempcode + 1+LINK_SIZE, tempcode, len);
        code += 1 + LINK_SIZE;
        len += 1 + LINK_SIZE;
        tempcode[0] = OP_ONCE;
        *code++ = OP_KET;
        PUTINC(code, 0, len);
        PUT(tempcode, 1, len);
        }


      /* In all case we no longer have a previous item. We also set the
      "follows varying string" flag for subsequently encountered reqbytes if
      it isn't already set and we have just passed a varying length item. */


      END_REPEAT:
      previous = NULL;
      cd->req_varyopt |= reqvary;
      break;



      /* Start of nested bracket sub-expression, or comment or lookahead or
      lookbehind or option setting or condition. First deal with special things
      that can come after a bracket; all are introduced by ?, and the appearance
      of any of them means that this is not a referencing group. They were
      checked for validity in the first pass over the string, so we don't have to
      check for syntax errors here.  */


      case '(':
      newoptions = options;
      skipbytes = 0;


      if (*(++ptr) == '?')
        {
        int set, unset;
        int *optset;


        switch (*(++ptr))
          {
          case '#':                 /* Comment; skip to ket */
          ptr++;
          while (*ptr != ')') ptr++;
          continue;


          case ':':                 /* Non-extracting bracket */
          bravalue = OP_BRA;
          ptr++;
          break;


          case '(':
          bravalue = OP_COND;       /* Conditional group */


          /* Condition to test for recursion */


          if (ptr[1] == 'R')
            {
            code[1+LINK_SIZE] = OP_CREF;
            PUT2(code, 2+LINK_SIZE, CREF_RECURSE);
            skipbytes = 3;
            ptr += 3;
            }


          /* Condition to test for a numbered subpattern match. We know that
          if a digit follows ( then there will just be digits until ) because
          the syntax was checked in the first pass. */


          else if ((digitab[ptr[1]] && ctype_digit) != 0)
            {
            int condref;                 /* Don't amalgamate; some compilers */
            condref = *(++ptr) - '0';    /* grumble at autoincrement in declaration */
            while (*(++ptr) != ')') condref = condref*10 + *ptr - '0';
            if (condref == 0)
              {
              *errorptr = ERR35;
              goto FAILED;
              }
            ptr++;
            code[1+LINK_SIZE] = OP_CREF;
            PUT2(code, 2+LINK_SIZE, condref);
            skipbytes = 3;
            }
          /* For conditions that are assertions, we just fall through, having
          set bravalue above. */
          break;


          case '=':                 /* Positive lookahead */
          bravalue = OP_ASSERT;
          ptr++;
          break;


          case '!':                 /* Negative lookahead */
          bravalue = OP_ASSERT_NOT;
          ptr++;
          break;


          case '<':                 /* Lookbehinds */
          switch (*(++ptr))
            {
            case '=':               /* Positive lookbehind */
            bravalue = OP_ASSERTBACK;
            ptr++;
            break;


            case '!':               /* Negative lookbehind */
            bravalue = OP_ASSERTBACK_NOT;
            ptr++;
            break;
            }
          break;


          case '>':                 /* One-time brackets */
          bravalue = OP_ONCE;
          ptr++;
          break;


          case 'C':                 /* Callout - may be followed by digits; */
          previous_callout = code;  /* Save for later completion */
          after_manual_callout = 1; /* Skip one item before completing */
          *code++ = OP_CALLOUT;     /* Already checked that the terminating */
            {                       /* closing parenthesis is present. */
            int n = 0;
            while ((digitab[*(++ptr)] & ctype_digit) != 0)
              n = n * 10 + *ptr - '0';
            if (n > 255)
              {
              *errorptr = ERR38;
              goto FAILED;
              }
            *code++ = n;
            PUT(code, 0, ptr - cd->start_pattern + 1);  /* Pattern offset */
            PUT(code, LINK_SIZE, 0);                    /* Default length */
            code += 2 * LINK_SIZE;
            }
          previous = NULL;
          continue;


          case 'P':                 /* Named subpattern handling */
          if (*(++ptr) == '<')      /* Definition */
            {
            int i, namelen;
            uschar *slot = cd->name_table;
            const uschar *name;     /* Don't amalgamate; some compilers */
            name = ++ptr;           /* grumble at autoincrement in declaration */


            while (*ptr++ != '>');
            namelen = ptr - name - 1;


            for (i = 0; i < cd->names_found; i++)
              {
              int crc = memcmp(name, slot+2, namelen);
              if (crc == 0)
                {
                if (slot[2+namelen] == 0)
                  {
                  *errorptr = ERR43;
                  goto FAILED;
                  }
                crc = -1;             /* Current name is substring */
                }
              if (crc < 0)
                {
                memmove(slot + cd->name_entry_size, slot,
                  (cd->names_found - i) * cd->name_entry_size);
                break;
                }
              slot += cd->name_entry_size;
              }


            PUT2(slot, 0, *brackets + 1);
            memcpy(slot + 2, name, namelen);
            slot[2+namelen] = 0;
            cd->names_found++;
            goto NUMBERED_GROUP;
            }


          if (*ptr == '=' || *ptr == '>')  /* Reference or recursion */
            {
            int i, namelen;
            int type = *ptr++;
            const uschar *name = ptr;
            uschar *slot = cd->name_table;


            while (*ptr != ')') ptr++;
            namelen = ptr - name;


            for (i = 0; i < cd->names_found; i++)
              {
              if (strncmp((char *)name, (char *)slot+2, namelen) == 0) break;
              slot += cd->name_entry_size;
              }
            if (i >= cd->names_found)
              {
              *errorptr = ERR15;
              goto FAILED;
              }


            recno = GET2(slot, 0);


            if (type == '>') goto HANDLE_RECURSION;  /* A few lines below */


            /* Back reference */


            previous = code;
            *code++ = OP_REF;
            PUT2INC(code, 0, recno);
            cd->backref_map |= (recno < 32)? (1 << recno) : 1;
            if (recno > cd->top_backref) cd->top_backref = recno;
            continue;
            }


          /* Should never happen */
          break;


          case 'R':                 /* Pattern recursion */
          ptr++;                    /* Same as (?0)      */
          /* Fall through */


          /* Recursion or "subroutine" call */


          case '0': case '1': case '2': case '3': case '4':
          case '5': case '6': case '7': case '8': case '9':
            {
            const uschar *called;
            recno = 0;
            while((digitab[*ptr] & ctype_digit) != 0)
              recno = recno * 10 + *ptr++ - '0';


            /* Come here from code above that handles a named recursion */


            HANDLE_RECURSION:


            previous = code;


            /* Find the bracket that is being referenced. Temporarily end the
            regex in case it doesn't exist. */


            *code = OP_END;
            called = (recno == 0)?
              cd->start_code : find_bracket(cd->start_code, utf8, recno);


            if (called == NULL)
              {
              *errorptr = ERR15;
              goto FAILED;
              }


            /* If the subpattern is still open, this is a recursive call. We
            check to see if this is a left recursion that could loop for ever,
            and diagnose that case. */


            if (GET(called, 1) == 0 && could_be_empty(called, code, bcptr, utf8))
              {
              *errorptr = ERR40;
              goto FAILED;
              }


            /* Insert the recursion/subroutine item */


            *code = OP_RECURSE;
            PUT(code, 1, called - cd->start_code);
            code += 1 + LINK_SIZE;
            }
          continue;


          /* Character after (? not specially recognized */


          default:                  /* Option setting */
          set = unset = 0;
          optset = &set;


          while (*ptr != ')' && *ptr != ':')
            {
            switch (*ptr++)
              {
              case '-': optset = &unset; break;


              case 'i': *optset |= PCRE_CASELESS; break;
              case 'm': *optset |= PCRE_MULTILINE; break;
              case 's': *optset |= PCRE_DOTALL; break;
              case 'x': *optset |= PCRE_EXTENDED; break;
              case 'U': *optset |= PCRE_UNGREEDY; break;
              case 'X': *optset |= PCRE_EXTRA; break;
              }
            }


          /* Set up the changed option bits, but don't change anything yet. */


          newoptions = (options | set) & (~unset);


          /* If the options ended with ')' this is not the start of a nested
          group with option changes, so the options change at this level. Compile
          code to change the ims options if this setting actually changes any of
          them. We also pass the new setting back so that it can be put at the
          start of any following branches, and when this group ends (if we are in
          a group), a resetting item can be compiled.


          Note that if this item is right at the start of the pattern, the
          options will have been abstracted and made global, so there will be no
          change to compile. */


          if (*ptr == ')')
            {
            if ((options & PCRE_IMS) != (newoptions & PCRE_IMS))
              {
              *code++ = OP_OPT;
              *code++ = newoptions & PCRE_IMS;
              }


            /* Change options at this level, and pass them back for use
            in subsequent branches. Reset the greedy defaults and the case
            value for firstbyte and reqbyte. */


            *optionsptr = options = newoptions;
            greedy_default = ((newoptions & PCRE_UNGREEDY) != 0);
            greedy_non_default = greedy_default ^ 1;
            req_caseopt = ((options & PCRE_CASELESS) != 0)? REQ_CASELESS : 0;


            previous = NULL;       /* This item can't be repeated */
            continue;              /* It is complete */
            }


          /* If the options ended with ':' we are heading into a nested group
          with possible change of options. Such groups are non-capturing and are
          not assertions of any kind. All we need to do is skip over the ':';
          the newoptions value is handled below. */


          bravalue = OP_BRA;
          ptr++;
          }
        }


      /* If PCRE_NO_AUTO_CAPTURE is set, all unadorned brackets become
      non-capturing and behave like (?:...) brackets */


      else if ((options & PCRE_NO_AUTO_CAPTURE) != 0)
        {
        bravalue = OP_BRA;
        }


      /* Else we have a referencing group; adjust the opcode. If the bracket
      number is greater than EXTRACT_BASIC_MAX, we set the opcode one higher, and
      arrange for the true number to follow later, in an OP_BRANUMBER item. */


      else
        {
        NUMBERED_GROUP:
        if (++(*brackets) > EXTRACT_BASIC_MAX)
          {
          bravalue = OP_BRA + EXTRACT_BASIC_MAX + 1;
          code[1+LINK_SIZE] = OP_BRANUMBER;
          PUT2(code, 2+LINK_SIZE, *brackets);
          skipbytes = 3;
          }
        else bravalue = OP_BRA + *brackets;
        }


      /* Process nested bracketed re. Assertions may not be repeated, but other
      kinds can be. We copy code into a non-register variable in order to be able
      to pass its address because some compilers complain otherwise. Pass in a
      new setting for the ims options if they have changed. */


      previous = (bravalue >= OP_ONCE)? code : NULL;
      *code = bravalue;
      tempcode = code;
      tempreqvary = cd->req_varyopt;     /* Save value before bracket */


      if (!compile_regex(
           newoptions,                   /* The complete new option state */
           options & PCRE_IMS,           /* The previous ims option state */
           brackets,                     /* Extracting bracket count */
           &tempcode,                    /* Where to put code (updated) */
           &ptr,                         /* Input pointer (updated) */
           errorptr,                     /* Where to put an error message */
           (bravalue == OP_ASSERTBACK ||
            bravalue == OP_ASSERTBACK_NOT), /* TRUE if back assert */
           skipbytes,                    /* Skip over OP_COND/OP_BRANUMBER */
           &subfirstbyte,                /* For possible first char */
           &subreqbyte,                  /* For possible last char */
           bcptr,                        /* Current branch chain */
           cd))                          /* Tables block */
        goto FAILED;


      /* At the end of compiling, code is still pointing to the start of the
      group, while tempcode has been updated to point past the end of the group
      and any option resetting that may follow it. The pattern pointer (ptr)
      is on the bracket. */


      /* If this is a conditional bracket, check that there are no more than
      two branches in the group. */


      else if (bravalue == OP_COND)
        {
        uschar *tc = code;
        condcount = 0;


        do {
           condcount++;
           tc += GET(tc,1);
           }
        while (*tc != OP_KET);


        if (condcount > 2)
          {
          *errorptr = ERR27;
          goto FAILED;
          }


        /* If there is just one branch, we must not make use of its firstbyte or
        reqbyte, because this is equivalent to an empty second branch. */


        if (condcount == 1) subfirstbyte = subreqbyte = REQ_NONE;
        }


      /* Handle updating of the required and first characters. Update for normal
      brackets of all kinds, and conditions with two branches (see code above).
      If the bracket is followed by a quantifier with zero repeat, we have to
      back off. Hence the definition of zeroreqbyte and zerofirstbyte outside the
      main loop so that they can be accessed for the back off. */


      zeroreqbyte = reqbyte;
      zerofirstbyte = firstbyte;
      groupsetfirstbyte = FALSE;


      if (bravalue >= OP_BRA || bravalue == OP_ONCE || bravalue == OP_COND)
        {
        /* If we have not yet set a firstbyte in this branch, take it from the
        subpattern, remembering that it was set here so that a repeat of more
        than one can replicate it as reqbyte if necessary. If the subpattern has
        no firstbyte, set "none" for the whole branch. In both cases, a zero
        repeat forces firstbyte to "none". */


        if (firstbyte == REQ_UNSET)
          {
          if (subfirstbyte >= 0)
            {
            firstbyte = subfirstbyte;
            groupsetfirstbyte = TRUE;
            }
          else firstbyte = REQ_NONE;
          zerofirstbyte = REQ_NONE;
          }


        /* If firstbyte was previously set, convert the subpattern's firstbyte
        into reqbyte if there wasn't one, using the vary flag that was in
        existence beforehand. */


        else if (subfirstbyte >= 0 && subreqbyte < 0)
          subreqbyte = subfirstbyte | tempreqvary;


        /* If the subpattern set a required byte (or set a first byte that isn't
        really the first byte - see above), set it. */


        if (subreqbyte >= 0) reqbyte = subreqbyte;
        }


      /* For a forward assertion, we take the reqbyte, if set. This can be
      helpful if the pattern that follows the assertion doesn't set a different
      char. For example, it's useful for /(?=abcde).+/. We can't set firstbyte
      for an assertion, however because it leads to incorrect effect for patterns
      such as /(?=a)a.+/ when the "real" "a" would then become a reqbyte instead
      of a firstbyte. This is overcome by a scan at the end if there's no
      firstbyte, looking for an asserted first char. */


      else if (bravalue == OP_ASSERT && subreqbyte >= 0) reqbyte = subreqbyte;


      /* Now update the main code pointer to the end of the group. */


      code = tempcode;


      /* Error if hit end of pattern */


      if (*ptr != ')')
        {
        *errorptr = ERR14;
        goto FAILED;
        }
      break;


      /* Check \ for being a real metacharacter; if not, fall through and handle
      it as a data character at the start of a string. Escape items are checked
      for validity in the pre-compiling pass. */


      case '\\':
      tempptr = ptr;
      c = check_escape(&ptr, errorptr, *brackets, options, FALSE);


      /* Handle metacharacters introduced by \. For ones like \d, the ESC_ values
      are arranged to be the negation of the corresponding OP_values. For the
      back references, the values are ESC_REF plus the reference number. Only
      back references and those types that consume a character may be repeated.
      We can test for values between ESC_b and ESC_Z for the latter; this may
      have to change if any new ones are ever created. */


      if (c < 0)
        {
        if (-c == ESC_Q)            /* Handle start of quoted string */
          {
          if (ptr[1] == '\\' && ptr[2] == 'E') ptr += 2; /* avoid empty string */
            else inescq = TRUE;
          continue;
          }


        /* For metasequences that actually match a character, we disable the
        setting of a first character if it hasn't already been set. */


        if (firstbyte == REQ_UNSET && -c > ESC_b && -c < ESC_Z)
          firstbyte = REQ_NONE;


        /* Set values to reset to if this is followed by a zero repeat. */


        zerofirstbyte = firstbyte;
        zeroreqbyte = reqbyte;


        /* Back references are handled specially */


        if (-c >= ESC_REF)
          {
          int number = -c - ESC_REF;
          previous = code;
          *code++ = OP_REF;
          PUT2INC(code, 0, number);
          }


        /* So are Unicode property matches, if supported. We know that get_ucp
        won't fail because it was tested in the pre-pass. */


  #ifdef SUPPORT_UCP
        else if (-c == ESC_P || -c == ESC_p)
          {
          BOOL negated;
          int value = get_ucp(&ptr, &negated, errorptr);
          previous = code;
          *code++ = ((-c == ESC_p) != negated)? OP_PROP : OP_NOTPROP;
          *code++ = value;
          }
  #endif


        /* For the rest, we can obtain the OP value by negating the escape
        value */


        else
          {
          previous = (-c > ESC_b && -c < ESC_Z)? code : NULL;
          *code++ = -c;
          }
        continue;
        }


      /* We have a data character whose value is in c. In UTF-8 mode it may have
      a value > 127. We set its representation in the length/buffer, and then
      handle it as a data character. */


  #ifdef SUPPORT_UTF8
      if (utf8 && c > 127)
        mclength = ord2utf8(c, mcbuffer);
      else
  #endif


       {
       mcbuffer[0] = c;
       mclength = 1;
       }


      goto ONE_CHAR;


      /* Handle a literal character. It is guaranteed not to be whitespace or #
      when the extended flag is set. If we are in UTF-8 mode, it may be a
      multi-byte literal character. */


      default:
      NORMAL_CHAR:
      mclength = 1;
      mcbuffer[0] = c;


  #ifdef SUPPORT_UTF8
      if (utf8 && (c & 0xc0) == 0xc0)
        {
        while ((ptr[1] & 0xc0) == 0x80)
          mcbuffer[mclength++] = *(++ptr);
        }
  #endif


      /* At this point we have the character's bytes in mcbuffer, and the length
      in mclength. When not in UTF-8 mode, the length is always 1. */


      ONE_CHAR:
      previous = code;
      *code++ = ((options & PCRE_CASELESS) != 0)? OP_CHARNC : OP_CHAR;
      for (c = 0; c < mclength; c++) *code++ = mcbuffer[c];


      /* Set the first and required bytes appropriately. If no previous first
      byte, set it from this character, but revert to none on a zero repeat.
      Otherwise, leave the firstbyte value alone, and don't change it on a zero
      repeat. */


      if (firstbyte == REQ_UNSET)
        {
        zerofirstbyte = REQ_NONE;
        zeroreqbyte = reqbyte;


        /* If the character is more than one byte long, we can set firstbyte
        only if it is not to be matched caselessly. */


        if (mclength == 1 || req_caseopt == 0)
          {
          firstbyte = mcbuffer[0] | req_caseopt;
          if (mclength != 1) reqbyte = code[-1] | cd->req_varyopt;
          }
        else firstbyte = reqbyte = REQ_NONE;
        }


      /* firstbyte was previously set; we can set reqbyte only the length is
      1 or the matching is caseful. */


      else
        {
        zerofirstbyte = firstbyte;
        zeroreqbyte = reqbyte;
        if (mclength == 1 || req_caseopt == 0)
          reqbyte = code[-1] | req_caseopt | cd->req_varyopt;
        }


      break;            /* End of literal character handling */
      }
    }                   /* end of big loop */


/* Control never reaches here by falling through, only by a goto for all the
error states. Pass back the position in the pattern so that it can be displayed
to the user for diagnosing the error. */

FAILED:
*ptrptr = ptr;
return FALSE;
}




  /*************************************************
  *     Compile sequence of alternatives           *
  *************************************************/


/* On entry, ptr is pointing past the bracket character, but on return
it points to the closing bracket, or vertical bar, or end of string.
The code variable is pointing at the byte into which the BRA operator has been
stored. If the ims options are changed at the start (for a (?ims: group) or
during any branch, we need to insert an OP_OPT item at the start of every
following branch to ensure they get set correctly at run time, and also pass
the new options into every subsequent branch compile.

  Argument:
    options        option bits, including any changes for this subpattern
    oldims         previous settings of ims option bits
    brackets       -> int containing the number of extracting brackets used
    codeptr        -> the address of the current code pointer
    ptrptr         -> the address of the current pattern pointer
    errorptr       -> pointer to error message
    lookbehind     TRUE if this is a lookbehind assertion
    skipbytes      skip this many bytes at start (for OP_COND, OP_BRANUMBER)
    firstbyteptr   place to put the first required character, or a negative number
    reqbyteptr     place to put the last required character, or a negative number
    bcptr          pointer to the chain of currently open branches
    cd             points to the data block with tables pointers etc.


  Returns:      TRUE on success
  */


  static BOOL
  compile_regex(int options, int oldims, int *brackets, uschar **codeptr,
    const uschar **ptrptr, const char **errorptr, BOOL lookbehind, int skipbytes,
    int *firstbyteptr, int *reqbyteptr, branch_chain *bcptr, compile_data *cd)
  {
  const uschar *ptr = *ptrptr;
  uschar *code = *codeptr;
  uschar *last_branch = code;
  uschar *start_bracket = code;
  uschar *reverse_count = NULL;
  int firstbyte, reqbyte;
  int branchfirstbyte, branchreqbyte;
  branch_chain bc;


bc.outer = bcptr;
bc.current = code;

firstbyte = reqbyte = REQ_UNSET;

/* Offset is set zero to mark that this bracket is still open */

PUT(code, 1, 0);
code += 1 + LINK_SIZE + skipbytes;

/* Loop for each alternative branch */

  for (;;)
    {
    /* Handle a change of ims options at the start of the branch */


    if ((options & PCRE_IMS) != oldims)
      {
      *code++ = OP_OPT;
      *code++ = options & PCRE_IMS;
      }


    /* Set up dummy OP_REVERSE if lookbehind assertion */


    if (lookbehind)
      {
      *code++ = OP_REVERSE;
      reverse_count = code;
      PUTINC(code, 0, 0);
      }


    /* Now compile the branch */


    if (!compile_branch(&options, brackets, &code, &ptr, errorptr,
          &branchfirstbyte, &branchreqbyte, &bc, cd))
      {
      *ptrptr = ptr;
      return FALSE;
      }


    /* If this is the first branch, the firstbyte and reqbyte values for the
    branch become the values for the regex. */


    if (*last_branch != OP_ALT)
      {
      firstbyte = branchfirstbyte;
      reqbyte = branchreqbyte;
      }


    /* If this is not the first branch, the first char and reqbyte have to
    match the values from all the previous branches, except that if the previous
    value for reqbyte didn't have REQ_VARY set, it can still match, and we set
    REQ_VARY for the regex. */


    else
      {
      /* If we previously had a firstbyte, but it doesn't match the new branch,
      we have to abandon the firstbyte for the regex, but if there was previously
      no reqbyte, it takes on the value of the old firstbyte. */


      if (firstbyte >= 0 && firstbyte != branchfirstbyte)
        {
        if (reqbyte < 0) reqbyte = firstbyte;
        firstbyte = REQ_NONE;
        }


      /* If we (now or from before) have no firstbyte, a firstbyte from the
      branch becomes a reqbyte if there isn't a branch reqbyte. */


      if (firstbyte < 0 && branchfirstbyte >= 0 && branchreqbyte < 0)
          branchreqbyte = branchfirstbyte;


      /* Now ensure that the reqbytes match */


      if ((reqbyte & ~REQ_VARY) != (branchreqbyte & ~REQ_VARY))
        reqbyte = REQ_NONE;
      else reqbyte |= branchreqbyte;   /* To "or" REQ_VARY */
      }


    /* If lookbehind, check that this branch matches a fixed-length string,
    and put the length into the OP_REVERSE item. Temporarily mark the end of
    the branch with OP_END. */


    if (lookbehind)
      {
      int length;
      *code = OP_END;
      length = find_fixedlength(last_branch, options);
      DPRINTF(("fixed length = %d\n", length));
      if (length < 0)
        {
        *errorptr = (length == -2)? ERR36 : ERR25;
        *ptrptr = ptr;
        return FALSE;
        }
      PUT(reverse_count, 0, length);
      }


    /* Reached end of expression, either ')' or end of pattern. Go back through
    the alternative branches and reverse the chain of offsets, with the field in
    the BRA item now becoming an offset to the first alternative. If there are
    no alternatives, it points to the end of the group. The length in the
    terminating ket is always the length of the whole bracketed item. If any of
    the ims options were changed inside the group, compile a resetting op-code
    following, except at the very end of the pattern. Return leaving the pointer
    at the terminating char. */


    if (*ptr != '|')
      {
      int length = code - last_branch;
      do
        {
        int prev_length = GET(last_branch, 1);
        PUT(last_branch, 1, length);
        length = prev_length;
        last_branch -= length;
        }
      while (length > 0);


      /* Fill in the ket */


      *code = OP_KET;
      PUT(code, 1, code - start_bracket);
      code += 1 + LINK_SIZE;


      /* Resetting option if needed */


      if ((options & PCRE_IMS) != oldims && *ptr == ')')
        {
        *code++ = OP_OPT;
        *code++ = oldims;
        }


      /* Set values to pass back */


      *codeptr = code;
      *ptrptr = ptr;
      *firstbyteptr = firstbyte;
      *reqbyteptr = reqbyte;
      return TRUE;
      }


    /* Another branch follows; insert an "or" node. Its length field points back
    to the previous branch while the bracket remains open. At the end the chain
    is reversed. It's done like this so that the start of the bracket has a
    zero offset until it is closed, making it possible to detect recursion. */


    *code = OP_ALT;
    PUT(code, 1, code - last_branch);
    bc.current = last_branch = code;
    code += 1 + LINK_SIZE;
    ptr++;
    }
  /* Control never reaches here */
  }





  /*************************************************
  *          Check for anchored expression         *
  *************************************************/


/* Try to find out if this is an anchored regular expression. Consider each
alternative branch. If they all start with OP_SOD or OP_CIRC, or with a bracket
all of whose alternatives start with OP_SOD or OP_CIRC (recurse ad lib), then
it's anchored. However, if this is a multiline pattern, then only OP_SOD
counts, since OP_CIRC can match in the middle.

We can also consider a regex to be anchored if OP_SOM starts all its branches.
This is the code for \G, which means "match at start of match position, taking
into account the match offset".

A branch is also implicitly anchored if it starts with .* and DOTALL is set,
because that will try the rest of the pattern at all possible matching points,
so there is no point trying again.... er ....

.... except when the .* appears inside capturing parentheses, and there is a
subsequent back reference to those parentheses. We haven't enough information
to catch that case precisely.

At first, the best we could do was to detect when .* was in capturing brackets
and the highest back reference was greater than or equal to that level.
However, by keeping a bitmap of the first 31 back references, we can catch some
of the more common cases more precisely.

  Arguments:
    code           points to start of expression (the bracket)
    options        points to the options setting
    bracket_map    a bitmap of which brackets we are inside while testing; this
                    handles up to substring 31; after that we just have to take
                    the less precise approach
    backref_map    the back reference bitmap


  Returns:     TRUE or FALSE
  */


  static BOOL
  is_anchored(register const uschar *code, int *options, unsigned int bracket_map,
    unsigned int backref_map)
  {
  do {
     const uschar *scode =
       first_significant_code(code + 1+LINK_SIZE, options, PCRE_MULTILINE, FALSE);
     register int op = *scode;


     /* Capturing brackets */


     if (op > OP_BRA)
       {
       int new_map;
       op -= OP_BRA;
       if (op > EXTRACT_BASIC_MAX) op = GET2(scode, 2+LINK_SIZE);
       new_map = bracket_map | ((op < 32)? (1 << op) : 1);
       if (!is_anchored(scode, options, new_map, backref_map)) return FALSE;
       }


     /* Other brackets */


     else if (op == OP_BRA || op == OP_ASSERT || op == OP_ONCE || op == OP_COND)
       {
       if (!is_anchored(scode, options, bracket_map, backref_map)) return FALSE;
       }


     /* .* is not anchored unless DOTALL is set and it isn't in brackets that
     are or may be referenced. */


     else if ((op == OP_TYPESTAR || op == OP_TYPEMINSTAR) &&
              (*options & PCRE_DOTALL) != 0)
       {
       if (scode[1] != OP_ANY || (bracket_map & backref_map) != 0) return FALSE;
       }


     /* Check for explicit anchoring */


     else if (op != OP_SOD && op != OP_SOM &&
             ((*options & PCRE_MULTILINE) != 0 || op != OP_CIRC))
       return FALSE;
     code += GET(code, 1);
     }
  while (*code == OP_ALT);   /* Loop for each alternative */
  return TRUE;
  }




  /*************************************************
  *         Check for starting with ^ or .*        *
  *************************************************/


/* This is called to find out if every branch starts with ^ or .* so that
"first char" processing can be done to speed things up in multiline
matching and for non-DOTALL patterns that start with .* (which must start at
the beginning or after \n). As in the case of is_anchored() (see above), we
have to take account of back references to capturing brackets that contain .*
because in that case we can't make the assumption.

  Arguments:
    code           points to start of expression (the bracket)
    bracket_map    a bitmap of which brackets we are inside while testing; this
                    handles up to substring 31; after that we just have to take
                    the less precise approach
    backref_map    the back reference bitmap


  Returns:         TRUE or FALSE
  */


  static BOOL
  is_startline(const uschar *code, unsigned int bracket_map,
    unsigned int backref_map)
  {
  do {
     const uschar *scode = first_significant_code(code + 1+LINK_SIZE, NULL, 0,
       FALSE);
     register int op = *scode;


     /* Capturing brackets */


     if (op > OP_BRA)
       {
       int new_map;
       op -= OP_BRA;
       if (op > EXTRACT_BASIC_MAX) op = GET2(scode, 2+LINK_SIZE);
       new_map = bracket_map | ((op < 32)? (1 << op) : 1);
       if (!is_startline(scode, new_map, backref_map)) return FALSE;
       }


     /* Other brackets */


     else if (op == OP_BRA || op == OP_ASSERT || op == OP_ONCE || op == OP_COND)
       { if (!is_startline(scode, bracket_map, backref_map)) return FALSE; }


     /* .* means "start at start or after \n" if it isn't in brackets that
     may be referenced. */


     else if (op == OP_TYPESTAR || op == OP_TYPEMINSTAR)
       {
       if (scode[1] != OP_ANY || (bracket_map & backref_map) != 0) return FALSE;
       }


     /* Check for explicit circumflex */


     else if (op != OP_CIRC) return FALSE;


     /* Move on to the next alternative */


     code += GET(code, 1);
     }
  while (*code == OP_ALT);  /* Loop for each alternative */
  return TRUE;
  }




  /*************************************************
  *       Check for asserted fixed first char      *
  *************************************************/


/* During compilation, the "first char" settings from forward assertions are
discarded, because they can cause conflicts with actual literals that follow.
However, if we end up without a first char setting for an unanchored pattern,
it is worth scanning the regex to see if there is an initial asserted first
char. If all branches start with the same asserted char, or with a bracket all
of whose alternatives start with the same asserted char (recurse ad lib), then
we return that char, otherwise -1.

  Arguments:
    code       points to start of expression (the bracket)
    options    pointer to the options (used to check casing changes)
    inassert   TRUE if in an assertion


  Returns:     -1 or the fixed first char
  */


  static int
  find_firstassertedchar(const uschar *code, int *options, BOOL inassert)
  {
  register int c = -1;
  do {
     int d;
     const uschar *scode =
       first_significant_code(code + 1+LINK_SIZE, options, PCRE_CASELESS, TRUE);
     register int op = *scode;


     if (op >= OP_BRA) op = OP_BRA;


     switch(op)
       {
       default:
       return -1;


       case OP_BRA:
       case OP_ASSERT:
       case OP_ONCE:
       case OP_COND:
       if ((d = find_firstassertedchar(scode, options, op == OP_ASSERT)) < 0)
         return -1;
       if (c < 0) c = d; else if (c != d) return -1;
       break;


       case OP_EXACT:       /* Fall through */
       scode += 2;


       case OP_CHAR:
       case OP_CHARNC:
       case OP_PLUS:
       case OP_MINPLUS:
       if (!inassert) return -1;
       if (c < 0)
         {
         c = scode[1];
         if ((*options & PCRE_CASELESS) != 0) c |= REQ_CASELESS;
         }
       else if (c != scode[1]) return -1;
       break;
       }


     code += GET(code, 1);
     }
  while (*code == OP_ALT);
  return c;
  }





  #ifdef SUPPORT_UTF8
  /*************************************************
  *         Validate a UTF-8 string                *
  *************************************************/


/* This function is called (optionally) at the start of compile or match, to
validate that a supposed UTF-8 string is actually valid. The early check means
that subsequent code can assume it is dealing with a valid string. The check
can be turned off for maximum performance, but then consequences of supplying
an invalid string are then undefined.

  Arguments:
    string       points to the string
    length       length of string, or -1 if the string is zero-terminated


  Returns:       < 0    if the string is a valid UTF-8 string
                 >= 0   otherwise; the value is the offset of the bad byte
  */


static int
valid_utf8(const uschar *string, int length)
{
register const uschar *p;

  if (length < 0)
    {
    for (p = string; *p != 0; p++);
    length = p - string;
    }


  for (p = string; length-- > 0; p++)
    {
    register int ab;
    register int c = *p;
    if (c < 128) continue;
    if ((c & 0xc0) != 0xc0) return p - string;
    ab = utf8_table4[c & 0x3f];  /* Number of additional bytes */
    if (length < ab) return p - string;
    length -= ab;


    /* Check top bits in the second byte */
    if ((*(++p) & 0xc0) != 0x80) return p - string;


    /* Check for overlong sequences for each different length */
    switch (ab)
      {
      /* Check for xx00 000x */
      case 1:
      if ((c & 0x3e) == 0) return p - string;
      continue;   /* We know there aren't any more bytes to check */


      /* Check for 1110 0000, xx0x xxxx */
      case 2:
      if (c == 0xe0 && (*p & 0x20) == 0) return p - string;
      break;


      /* Check for 1111 0000, xx00 xxxx */
      case 3:
      if (c == 0xf0 && (*p & 0x30) == 0) return p - string;
      break;


      /* Check for 1111 1000, xx00 0xxx */
      case 4:
      if (c == 0xf8 && (*p & 0x38) == 0) return p - string;
      break;


      /* Check for leading 0xfe or 0xff, and then for 1111 1100, xx00 00xx */
      case 5:
      if (c == 0xfe || c == 0xff ||
         (c == 0xfc && (*p & 0x3c) == 0)) return p - string;
      break;
      }


    /* Check for valid bytes after the 2nd, if any; all must start 10 */
    while (--ab > 0)
      {
      if ((*(++p) & 0xc0) != 0x80) return p - string;
      }
    }


return -1;
}
#endif



  /*************************************************
  *        Compile a Regular Expression            *
  *************************************************/


/* This function takes a string and returns a pointer to a block of store
holding a compiled version of the expression.

  Arguments:
    pattern      the regular expression
    options      various option bits
    errorptr     pointer to pointer to error text
    erroroffset  ptr offset in pattern where error was detected
    tables       pointer to character tables or NULL


  Returns:       pointer to compiled data block, or NULL on error,
                 with errorptr and erroroffset set
  */


  EXPORT pcre *
  pcre_compile(const char *pattern, int options, const char **errorptr,
    int *erroroffset, const unsigned char *tables)
  {
  real_pcre *re;
  int length = 1 + LINK_SIZE;      /* For initial BRA plus length */
  int c, firstbyte, reqbyte;
  int bracount = 0;
  int branch_extra = 0;
  int branch_newextra;
  int item_count = -1;
  int name_count = 0;
  int max_name_size = 0;
  int lastitemlength = 0;
  #ifdef SUPPORT_UTF8
  BOOL utf8;
  BOOL class_utf8;
  #endif
  BOOL inescq = FALSE;
  unsigned int brastackptr = 0;
  size_t size;
  uschar *code;
  const uschar *codestart;
  const uschar *ptr;
  compile_data compile_block;
  int brastack[BRASTACK_SIZE];
  uschar bralenstack[BRASTACK_SIZE];


/* We can't pass back an error message if errorptr is NULL; I guess the best we
can do is just return NULL. */

if (errorptr == NULL) return NULL;
*errorptr = NULL;

/* However, we can give a message for this error */

  if (erroroffset == NULL)
    {
    *errorptr = ERR16;
    return NULL;
    }
  *erroroffset = 0;


/* Can't support UTF8 unless PCRE has been compiled to include the code. */

  #ifdef SUPPORT_UTF8
  utf8 = (options & PCRE_UTF8) != 0;
  if (utf8 && (options & PCRE_NO_UTF8_CHECK) == 0 &&
       (*erroroffset = valid_utf8((uschar *)pattern, -1)) >= 0)
    {
    *errorptr = ERR44;
    return NULL;
    }
  #else
  if ((options & PCRE_UTF8) != 0)
    {
    *errorptr = ERR32;
    return NULL;
    }
  #endif


  if ((options & ~PUBLIC_OPTIONS) != 0)
    {
    *errorptr = ERR17;
    return NULL;
    }


/* Set up pointers to the individual character tables */

if (tables == NULL) tables = pcre_default_tables;
compile_block.lcc = tables + lcc_offset;
compile_block.fcc = tables + fcc_offset;
compile_block.cbits = tables + cbits_offset;
compile_block.ctypes = tables + ctypes_offset;

/* Maximum back reference and backref bitmap. This is updated for numeric
references during the first pass, but for named references during the actual
compile pass. The bitmap records up to 31 back references to help in deciding
whether (.*) can be treated as anchored or not. */

compile_block.top_backref = 0;
compile_block.backref_map = 0;

/* Reflect pattern for debugging output */

DPRINTF(("------------------------------------------------------------------\n"));
DPRINTF(("%s\n", pattern));

/* The first thing to do is to make a pass over the pattern to compute the
amount of store required to hold the compiled code. This does not have to be
perfect as long as errors are overestimates. At the same time we can detect any
flag settings right at the start, and extract them. Make an attempt to correct
for any counted white space if an "extended" flag setting appears late in the
pattern. We can't be so clever for #-comments. */

  ptr = (const uschar *)(pattern - 1);
  while ((c = *(++ptr)) != 0)
    {
    int min, max;
    int class_optcount;
    int bracket_length;
    int duplength;


    /* If we are inside a \Q...\E sequence, all chars are literal */


    if (inescq)
      {
      if ((options & PCRE_AUTO_CALLOUT) != 0) length += 2 + 2*LINK_SIZE;
      goto NORMAL_CHAR;
      }


    /* Otherwise, first check for ignored whitespace and comments */


    if ((options & PCRE_EXTENDED) != 0)
      {
      if ((compile_block.ctypes[c] & ctype_space) != 0) continue;
      if (c == '#')
        {
        /* The space before the ; is to avoid a warning on a silly compiler
        on the Macintosh. */
        while ((c = *(++ptr)) != 0 && c != NEWLINE) ;
        if (c == 0) break;
        continue;
        }
      }


    item_count++;    /* Is zero for the first non-comment item */


    /* Allow space for auto callout before every item except quantifiers. */


    if ((options & PCRE_AUTO_CALLOUT) != 0 &&
         c != '*' && c != '+' && c != '?' &&
         (c != '{' || !is_counted_repeat(ptr + 1)))
      length += 2 + 2*LINK_SIZE;


    switch(c)
      {
      /* A backslashed item may be an escaped data character or it may be a
      character type. */


      case '\\':
      c = check_escape(&ptr, errorptr, bracount, options, FALSE);
      if (*errorptr != NULL) goto PCRE_ERROR_RETURN;


      lastitemlength = 1;     /* Default length of last item for repeats */


      if (c >= 0)             /* Data character */
        {
        length += 2;          /* For a one-byte character */


  #ifdef SUPPORT_UTF8
        if (utf8 && c > 127)
          {
          int i;
          for (i = 0; i < sizeof(utf8_table1)/sizeof(int); i++)
            if (c <= utf8_table1[i]) break;
          length += i;
          lastitemlength += i;
          }
  #endif


        continue;
        }


      /* If \Q, enter "literal" mode */


      if (-c == ESC_Q)
        {
        inescq = TRUE;
        continue;
        }


      /* \X is supported only if Unicode property support is compiled */


  #ifndef SUPPORT_UCP
      if (-c == ESC_X)
        {
        *errorptr = ERR45;
        goto PCRE_ERROR_RETURN;
        }
  #endif


      /* \P and \p are for Unicode properties, but only when the support has
      been compiled. Each item needs 2 bytes. */


      else if (-c == ESC_P || -c == ESC_p)
        {
  #ifdef SUPPORT_UCP
        BOOL negated;
        length += 2;
        lastitemlength = 2;
        if (get_ucp(&ptr, &negated, errorptr) < 0) goto PCRE_ERROR_RETURN;
        continue;
  #else
        *errorptr = ERR45;
        goto PCRE_ERROR_RETURN;
  #endif
        }


      /* Other escapes need one byte */


      length++;


      /* A back reference needs an additional 2 bytes, plus either one or 5
      bytes for a repeat. We also need to keep the value of the highest
      back reference. */


      if (c <= -ESC_REF)
        {
        int refnum = -c - ESC_REF;
        compile_block.backref_map |= (refnum < 32)? (1 << refnum) : 1;
        if (refnum > compile_block.top_backref)
          compile_block.top_backref = refnum;
        length += 2;   /* For single back reference */
        if (ptr[1] == '{' && is_counted_repeat(ptr+2))
          {
          ptr = read_repeat_counts(ptr+2, &min, &max, errorptr);
          if (*errorptr != NULL) goto PCRE_ERROR_RETURN;
          if ((min == 0 && (max == 1 || max == -1)) ||
            (min == 1 && max == -1))
              length++;
          else length += 5;
          if (ptr[1] == '?') ptr++;
          }
        }
      continue;


      case '^':     /* Single-byte metacharacters */
      case '.':
      case '$':
      length++;
      lastitemlength = 1;
      continue;


      case '*':            /* These repeats won't be after brackets; */
      case '+':            /* those are handled separately */
      case '?':
      length++;
      goto POSESSIVE;      /* A few lines below */


      /* This covers the cases of braced repeats after a single char, metachar,
      class, or back reference. */


      case '{':
      if (!is_counted_repeat(ptr+1)) goto NORMAL_CHAR;
      ptr = read_repeat_counts(ptr+1, &min, &max, errorptr);
      if (*errorptr != NULL) goto PCRE_ERROR_RETURN;


      /* These special cases just insert one extra opcode */


      if ((min == 0 && (max == 1 || max == -1)) ||
        (min == 1 && max == -1))
          length++;


      /* These cases might insert additional copies of a preceding character. */


      else
        {
        if (min != 1)
          {
          length -= lastitemlength;   /* Uncount the original char or metachar */
          if (min > 0) length += 3 + lastitemlength;
          }
        length += lastitemlength + ((max > 0)? 3 : 1);
        }


      if (ptr[1] == '?') ptr++;      /* Needs no extra length */


      POSESSIVE:                     /* Test for possessive quantifier */
      if (ptr[1] == '+')
        {
        ptr++;
        length += 2 + 2*LINK_SIZE;   /* Allow for atomic brackets */
        }
      continue;


      /* An alternation contains an offset to the next branch or ket. If any ims
      options changed in the previous branch(es), and/or if we are in a
      lookbehind assertion, extra space will be needed at the start of the
      branch. This is handled by branch_extra. */


      case '|':
      length += 1 + LINK_SIZE + branch_extra;
      continue;


      /* A character class uses 33 characters provided that all the character
      values are less than 256. Otherwise, it uses a bit map for low valued
      characters, and individual items for others. Don't worry about character
      types that aren't allowed in classes - they'll get picked up during the
      compile. A character class that contains only one single-byte character
      uses 2 or 3 bytes, depending on whether it is negated or not. Notice this
      where we can. (In UTF-8 mode we can do this only for chars < 128.) */


      case '[':
      if (*(++ptr) == '^')
        {
        class_optcount = 10;  /* Greater than one */
        ptr++;
        }
      else class_optcount = 0;


  #ifdef SUPPORT_UTF8
      class_utf8 = FALSE;
  #endif


      /* Written as a "do" so that an initial ']' is taken as data */


      if (*ptr != 0) do
        {
        /* Inside \Q...\E everything is literal except \E */


        if (inescq)
          {
          if (*ptr != '\\' || ptr[1] != 'E') goto GET_ONE_CHARACTER;
          inescq = FALSE;
          ptr += 1;
          continue;
          }


        /* Outside \Q...\E, check for escapes */


        if (*ptr == '\\')
          {
          c = check_escape(&ptr, errorptr, bracount, options, TRUE);
          if (*errorptr != NULL) goto PCRE_ERROR_RETURN;


          /* \b is backspace inside a class; \X is literal */


          if (-c == ESC_b) c = '\b';
          else if (-c == ESC_X) c = 'X';


          /* \Q enters quoting mode */


          else if (-c == ESC_Q)
            {
            inescq = TRUE;
            continue;
            }


          /* Handle escapes that turn into characters */


          if (c >= 0) goto NON_SPECIAL_CHARACTER;


          /* Escapes that are meta-things. The normal ones just affect the
          bit map, but Unicode properties require an XCLASS extended item. */


          else
            {
            class_optcount = 10;         /* \d, \s etc; make sure > 1 */
  #ifdef SUPPORT_UTF8
            if (-c == ESC_p || -c == ESC_P)
              {
              if (!class_utf8)
                {
                class_utf8 = TRUE;
                length += LINK_SIZE + 2;
                }
              length += 2;
              }
  #endif
            }
          }


        /* Check the syntax for POSIX stuff. The bits we actually handle are
        checked during the real compile phase. */


        else if (*ptr == '[' && check_posix_syntax(ptr, &ptr, &compile_block))
          {
          ptr++;
          class_optcount = 10;    /* Make sure > 1 */
          }


        /* Anything else increments the possible optimization count. We have to
        detect ranges here so that we can compute the number of extra ranges for
        caseless wide characters when UCP support is available. If there are wide
        characters, we are going to have to use an XCLASS, even for single
        characters. */


        else
          {
          int d;


          GET_ONE_CHARACTER:


  #ifdef SUPPORT_UTF8
          if (utf8)
            {
            int extra = 0;
            GETCHARLEN(c, ptr, extra);
            ptr += extra;
            }
          else c = *ptr;
  #else
          c = *ptr;
  #endif


          /* Come here from handling \ above when it escapes to a char value */


          NON_SPECIAL_CHARACTER:
          class_optcount++;


          d = -1;
          if (ptr[1] == '-')
            {
            uschar const *hyptr = ptr++;
            if (ptr[1] == '\\')
              {
              ptr++;
              d = check_escape(&ptr, errorptr, bracount, options, TRUE);
              if (*errorptr != NULL) goto PCRE_ERROR_RETURN;
              if (-d == ESC_b) d = '\b';        /* backspace */
              else if (-d == ESC_X) d = 'X';    /* literal X in a class */
              }
            else if (ptr[1] != 0 && ptr[1] != ']')
              {
              ptr++;
  #ifdef SUPPORT_UTF8
              if (utf8)
                {
                int extra = 0;
                GETCHARLEN(d, ptr, extra);
                ptr += extra;
                }
              else
  #endif
              d = *ptr;
              }
            if (d < 0) ptr = hyptr;      /* go back to hyphen as data */
            }


          /* If d >= 0 we have a range. In UTF-8 mode, if the end is > 255, or >
          127 for caseless matching, we will need to use an XCLASS. */


          if (d >= 0)
            {
            class_optcount = 10;     /* Ensure > 1 */
            if (d < c)
              {
              *errorptr = ERR8;
              goto PCRE_ERROR_RETURN;
              }


  #ifdef SUPPORT_UTF8
            if (utf8 && (d > 255 || ((options & PCRE_CASELESS) != 0 && d > 127)))
              {
              uschar buffer[6];
              if (!class_utf8)         /* Allow for XCLASS overhead */
                {
                class_utf8 = TRUE;
                length += LINK_SIZE + 2;
                }


  #ifdef SUPPORT_UCP
              /* If we have UCP support, find out how many extra ranges are
              needed to map the other case of characters within this range. We
              have to mimic the range optimization here, because extending the
              range upwards might push d over a boundary that makes is use
              another byte in the UTF-8 representation. */


              if ((options & PCRE_CASELESS) != 0)
                {
                int occ, ocd;
                int cc = c;
                int origd = d;
                while (get_othercase_range(&cc, origd, &occ, &ocd))
                  {
                  if (occ >= c && ocd <= d) continue;   /* Skip embedded */


                  if (occ < c  && ocd >= c - 1)  /* Extend the basic range */
                    {                            /* if there is overlap,   */
                    c = occ;                     /* noting that if occ < c */
                    continue;                    /* we can't have ocd > d  */
                    }                            /* because a subrange is  */
                  if (ocd > d && occ <= d + 1)   /* always shorter than    */
                    {                            /* the basic range.       */
                    d = ocd;
                    continue;
                    }


                  /* An extra item is needed */


                  length += 1 + ord2utf8(occ, buffer) +
                    ((occ == ocd)? 0 : ord2utf8(ocd, buffer));
                  }
                }
  #endif  /* SUPPORT_UCP */


              /* The length of the (possibly extended) range */


              length += 1 + ord2utf8(c, buffer) + ord2utf8(d, buffer);
              }
  #endif  /* SUPPORT_UTF8 */


            }


          /* We have a single character. There is nothing to be done unless we
          are in UTF-8 mode. If the char is > 255, or 127 when caseless, we must
          allow for an XCL_SINGLE item, doubled for caselessness if there is UCP
          support. */


          else
            {
  #ifdef SUPPORT_UTF8
            if (utf8 && (c > 255 || ((options & PCRE_CASELESS) != 0 && c > 127)))
              {
              uschar buffer[6];
              class_optcount = 10;     /* Ensure > 1 */
              if (!class_utf8)         /* Allow for XCLASS overhead */
                {
                class_utf8 = TRUE;
                length += LINK_SIZE + 2;
                }
  #ifdef SUPPORT_UCP
              length += (((options & PCRE_CASELESS) != 0)? 2 : 1) *
                (1 + ord2utf8(c, buffer));
  #else   /* SUPPORT_UCP */
              length += 1 + ord2utf8(c, buffer);
  #endif  /* SUPPORT_UCP */
              }
  #endif  /* SUPPORT_UTF8 */
            }
          }
        }
      while (*(++ptr) != 0 && (inescq || *ptr != ']')); /* Concludes "do" above */


      if (*ptr == 0)                          /* Missing terminating ']' */
        {
        *errorptr = ERR6;
        goto PCRE_ERROR_RETURN;
        }


      /* We can optimize when there was only one optimizable character. Repeats
      for positive and negated single one-byte chars are handled by the general
      code. Here, we handle repeats for the class opcodes. */


      if (class_optcount == 1) length += 3; else
        {
        length += 33;


        /* A repeat needs either 1 or 5 bytes. If it is a possessive quantifier,
        we also need extra for wrapping the whole thing in a sub-pattern. */


        if (*ptr != 0 && ptr[1] == '{' && is_counted_repeat(ptr+2))
          {
          ptr = read_repeat_counts(ptr+2, &min, &max, errorptr);
          if (*errorptr != NULL) goto PCRE_ERROR_RETURN;
          if ((min == 0 && (max == 1 || max == -1)) ||
            (min == 1 && max == -1))
              length++;
          else length += 5;
          if (ptr[1] == '+')
            {
            ptr++;
            length += 2 + 2*LINK_SIZE;
            }
          else if (ptr[1] == '?') ptr++;
          }
        }
      continue;


      /* Brackets may be genuine groups or special things */


      case '(':
      branch_newextra = 0;
      bracket_length = 1 + LINK_SIZE;


      /* Handle special forms of bracket, which all start (? */


      if (ptr[1] == '?')
        {
        int set, unset;
        int *optset;


        switch (c = ptr[2])
          {
          /* Skip over comments entirely */
          case '#':
          ptr += 3;
          while (*ptr != 0 && *ptr != ')') ptr++;
          if (*ptr == 0)
            {
            *errorptr = ERR18;
            goto PCRE_ERROR_RETURN;
            }
          continue;


          /* Non-referencing groups and lookaheads just move the pointer on, and
          then behave like a non-special bracket, except that they don't increment
          the count of extracting brackets. Ditto for the "once only" bracket,
          which is in Perl from version 5.005. */


          case ':':
          case '=':
          case '!':
          case '>':
          ptr += 2;
          break;


          /* (?R) specifies a recursive call to the regex, which is an extension
          to provide the facility which can be obtained by (?p{perl-code}) in
          Perl 5.6. In Perl 5.8 this has become (??{perl-code}).


          From PCRE 4.00, items such as (?3) specify subroutine-like "calls" to
          the appropriate numbered brackets. This includes both recursive and
          non-recursive calls. (?R) is now synonymous with (?0). */


          case 'R':
          ptr++;


          case '0': case '1': case '2': case '3': case '4':
          case '5': case '6': case '7': case '8': case '9':
          ptr += 2;
          if (c != 'R')
            while ((digitab[*(++ptr)] & ctype_digit) != 0);
          if (*ptr != ')')
            {
            *errorptr = ERR29;
            goto PCRE_ERROR_RETURN;
            }
          length += 1 + LINK_SIZE;


          /* If this item is quantified, it will get wrapped inside brackets so
          as to use the code for quantified brackets. We jump down and use the
          code that handles this for real brackets. */


          if (ptr[1] == '+' || ptr[1] == '*' || ptr[1] == '?' || ptr[1] == '{')
            {
            length += 2 + 2 * LINK_SIZE;       /* to make bracketed */
            duplength = 5 + 3 * LINK_SIZE;
            goto HANDLE_QUANTIFIED_BRACKETS;
            }
          continue;


          /* (?C) is an extension which provides "callout" - to provide a bit of
          the functionality of the Perl (?{...}) feature. An optional number may
          follow (default is zero). */


          case 'C':
          ptr += 2;
          while ((digitab[*(++ptr)] & ctype_digit) != 0);
          if (*ptr != ')')
            {
            *errorptr = ERR39;
            goto PCRE_ERROR_RETURN;
            }
          length += 2 + 2*LINK_SIZE;
          continue;


          /* Named subpatterns are an extension copied from Python */


          case 'P':
          ptr += 3;
          if (*ptr == '<')
            {
            const uschar *p;    /* Don't amalgamate; some compilers */
            p = ++ptr;          /* grumble at autoincrement in declaration */
            while ((compile_block.ctypes[*ptr] & ctype_word) != 0) ptr++;
            if (*ptr != '>')
              {
              *errorptr = ERR42;
              goto PCRE_ERROR_RETURN;
              }
            name_count++;
            if (ptr - p > max_name_size) max_name_size = (ptr - p);
            break;
            }


          if (*ptr == '=' || *ptr == '>')
            {
            while ((compile_block.ctypes[*(++ptr)] & ctype_word) != 0);
            if (*ptr != ')')
              {
              *errorptr = ERR42;
              goto PCRE_ERROR_RETURN;
              }
            break;
            }


          /* Unknown character after (?P */


          *errorptr = ERR41;
          goto PCRE_ERROR_RETURN;


          /* Lookbehinds are in Perl from version 5.005 */


          case '<':
          ptr += 3;
          if (*ptr == '=' || *ptr == '!')
            {
            branch_newextra = 1 + LINK_SIZE;
            length += 1 + LINK_SIZE;         /* For the first branch */
            break;
            }
          *errorptr = ERR24;
          goto PCRE_ERROR_RETURN;


          /* Conditionals are in Perl from version 5.005. The bracket must either
          be followed by a number (for bracket reference) or by an assertion
          group, or (a PCRE extension) by 'R' for a recursion test. */


          case '(':
          if (ptr[3] == 'R' && ptr[4] == ')')
            {
            ptr += 4;
            length += 3;
            }
          else if ((digitab[ptr[3]] & ctype_digit) != 0)
            {
            ptr += 4;
            length += 3;
            while ((digitab[*ptr] & ctype_digit) != 0) ptr++;
            if (*ptr != ')')
              {
              *errorptr = ERR26;
              goto PCRE_ERROR_RETURN;
              }
            }
          else   /* An assertion must follow */
            {
            ptr++;   /* Can treat like ':' as far as spacing is concerned */
            if (ptr[2] != '?' ||
               (ptr[3] != '=' && ptr[3] != '!' && ptr[3] != '<') )
              {
              ptr += 2;    /* To get right offset in message */
              *errorptr = ERR28;
              goto PCRE_ERROR_RETURN;
              }
            }
          break;


          /* Else loop checking valid options until ) is met. Anything else is an
          error. If we are without any brackets, i.e. at top level, the settings
          act as if specified in the options, so massage the options immediately.
          This is for backward compatibility with Perl 5.004. */


          default:
          set = unset = 0;
          optset = &set;
          ptr += 2;


          for (;; ptr++)
            {
            c = *ptr;
            switch (c)
              {
              case 'i':
              *optset |= PCRE_CASELESS;
              continue;


              case 'm':
              *optset |= PCRE_MULTILINE;
              continue;


              case 's':
              *optset |= PCRE_DOTALL;
              continue;


              case 'x':
              *optset |= PCRE_EXTENDED;
              continue;


              case 'X':
              *optset |= PCRE_EXTRA;
              continue;


              case 'U':
              *optset |= PCRE_UNGREEDY;
              continue;


              case '-':
              optset = &unset;
              continue;


              /* A termination by ')' indicates an options-setting-only item; if
              this is at the very start of the pattern (indicated by item_count
              being zero), we use it to set the global options. This is helpful
              when analyzing the pattern for first characters, etc. Otherwise
              nothing is done here and it is handled during the compiling
              process.


              [Historical note: Up to Perl 5.8, options settings at top level
              were always global settings, wherever they appeared in the pattern.
              That is, they were equivalent to an external setting. From 5.8
              onwards, they apply only to what follows (which is what you might
              expect).] */


              case ')':
              if (item_count == 0)
                {
                options = (options | set) & (~unset);
                set = unset = 0;     /* To save length */
                item_count--;        /* To allow for several */
                }


              /* Fall through */


              /* A termination by ':' indicates the start of a nested group with
              the given options set. This is again handled at compile time, but
              we must allow for compiled space if any of the ims options are
              set. We also have to allow for resetting space at the end of
              the group, which is why 4 is added to the length and not just 2.
              If there are several changes of options within the same group, this
              will lead to an over-estimate on the length, but this shouldn't
              matter very much. We also have to allow for resetting options at
              the start of any alternations, which we do by setting
              branch_newextra to 2. Finally, we record whether the case-dependent
              flag ever changes within the regex. This is used by the "required
              character" code. */


              case ':':
              if (((set|unset) & PCRE_IMS) != 0)
                {
                length += 4;
                branch_newextra = 2;
                if (((set|unset) & PCRE_CASELESS) != 0) options |= PCRE_ICHANGED;
                }
              goto END_OPTIONS;


              /* Unrecognized option character */


              default:
              *errorptr = ERR12;
              goto PCRE_ERROR_RETURN;
              }
            }


          /* If we hit a closing bracket, that's it - this is a freestanding
          option-setting. We need to ensure that branch_extra is updated if
          necessary. The only values branch_newextra can have here are 0 or 2.
          If the value is 2, then branch_extra must either be 2 or 5, depending
          on whether this is a lookbehind group or not. */


          END_OPTIONS:
          if (c == ')')
            {
            if (branch_newextra == 2 &&
                (branch_extra == 0 || branch_extra == 1+LINK_SIZE))
              branch_extra += branch_newextra;
            continue;
            }


          /* If options were terminated by ':' control comes here. Fall through
          to handle the group below. */
          }
        }


      /* Extracting brackets must be counted so we can process escapes in a
      Perlish way. If the number exceeds EXTRACT_BASIC_MAX we are going to
      need an additional 3 bytes of store per extracting bracket. However, if
      PCRE_NO_AUTO)CAPTURE is set, unadorned brackets become non-capturing, so we
      must leave the count alone (it will aways be zero). */


      else if ((options & PCRE_NO_AUTO_CAPTURE) == 0)
        {
        bracount++;
        if (bracount > EXTRACT_BASIC_MAX) bracket_length += 3;
        }


      /* Save length for computing whole length at end if there's a repeat that
      requires duplication of the group. Also save the current value of
      branch_extra, and start the new group with the new value. If non-zero, this
      will either be 2 for a (?imsx: group, or 3 for a lookbehind assertion. */


      if (brastackptr >= sizeof(brastack)/sizeof(int))
        {
        *errorptr = ERR19;
        goto PCRE_ERROR_RETURN;
        }


      bralenstack[brastackptr] = branch_extra;
      branch_extra = branch_newextra;


      brastack[brastackptr++] = length;
      length += bracket_length;
      continue;


      /* Handle ket. Look for subsequent max/min; for certain sets of values we
      have to replicate this bracket up to that many times. If brastackptr is
      0 this is an unmatched bracket which will generate an error, but take care
      not to try to access brastack[-1] when computing the length and restoring
      the branch_extra value. */


      case ')':
      length += 1 + LINK_SIZE;
      if (brastackptr > 0)
        {
        duplength = length - brastack[--brastackptr];
        branch_extra = bralenstack[brastackptr];
        }
      else duplength = 0;


      /* The following code is also used when a recursion such as (?3) is
      followed by a quantifier, because in that case, it has to be wrapped inside
      brackets so that the quantifier works. The value of duplength must be
      set before arrival. */


      HANDLE_QUANTIFIED_BRACKETS:


      /* Leave ptr at the final char; for read_repeat_counts this happens
      automatically; for the others we need an increment. */


      if ((c = ptr[1]) == '{' && is_counted_repeat(ptr+2))
        {
        ptr = read_repeat_counts(ptr+2, &min, &max, errorptr);
        if (*errorptr != NULL) goto PCRE_ERROR_RETURN;
        }
      else if (c == '*') { min = 0; max = -1; ptr++; }
      else if (c == '+') { min = 1; max = -1; ptr++; }
      else if (c == '?') { min = 0; max = 1;  ptr++; }
      else { min = 1; max = 1; }


      /* If the minimum is zero, we have to allow for an OP_BRAZERO before the
      group, and if the maximum is greater than zero, we have to replicate
      maxval-1 times; each replication acquires an OP_BRAZERO plus a nesting
      bracket set. */


      if (min == 0)
        {
        length++;
        if (max > 0) length += (max - 1) * (duplength + 3 + 2*LINK_SIZE);
        }


      /* When the minimum is greater than zero, we have to replicate up to
      minval-1 times, with no additions required in the copies. Then, if there
      is a limited maximum we have to replicate up to maxval-1 times allowing
      for a BRAZERO item before each optional copy and nesting brackets for all
      but one of the optional copies. */


      else
        {
        length += (min - 1) * duplength;
        if (max > min)   /* Need this test as max=-1 means no limit */
          length += (max - min) * (duplength + 3 + 2*LINK_SIZE)
            - (2 + 2*LINK_SIZE);
        }


      /* Allow space for once brackets for "possessive quantifier" */


      if (ptr[1] == '+')
        {
        ptr++;
        length += 2 + 2*LINK_SIZE;
        }
      continue;


      /* Non-special character. It won't be space or # in extended mode, so it is
      always a genuine character. If we are in a \Q...\E sequence, check for the
      end; if not, we have a literal. */


      default:
      NORMAL_CHAR:


      if (inescq && c == '\\' && ptr[1] == 'E')
        {
        inescq = FALSE;
        ptr++;
        continue;
        }


      length += 2;          /* For a one-byte character */
      lastitemlength = 1;   /* Default length of last item for repeats */


      /* In UTF-8 mode, check for additional bytes. */


  #ifdef SUPPORT_UTF8
      if (utf8 && (c & 0xc0) == 0xc0)
        {
        while ((ptr[1] & 0xc0) == 0x80)         /* Can't flow over the end */
          {                                     /* because the end is marked */
          lastitemlength++;                     /* by a zero byte. */
          length++;
          ptr++;
          }
        }
  #endif


      continue;
      }
    }


  length += 2 + LINK_SIZE;    /* For final KET and END */


  if ((options & PCRE_AUTO_CALLOUT) != 0)
    length += 2 + 2*LINK_SIZE;  /* For final callout */


  if (length > MAX_PATTERN_SIZE)
    {
    *errorptr = ERR20;
    return NULL;
    }


/* Compute the size of data block needed and get it, either from malloc or
externally provided function. */

size = length + sizeof(real_pcre) + name_count * (max_name_size + 3);
re = (real_pcre *)(pcre_malloc)(size);

  if (re == NULL)
    {
    *errorptr = ERR21;
    return NULL;
    }


/* Put in the magic number, and save the sizes, options, and character table
pointer. NULL is used for the default character tables. The nullpad field is at
the end; it's there to help in the case when a regex compiled on a system with
4-byte pointers is run on another with 8-byte pointers. */

re->magic_number = MAGIC_NUMBER;
re->size = size;
re->options = options;
re->dummy1 = re->dummy2 = 0;
re->name_table_offset = sizeof(real_pcre);
re->name_entry_size = max_name_size + 3;
re->name_count = name_count;
re->tables = (tables == pcre_default_tables)? NULL : tables;
re->nullpad = NULL;

/* The starting points of the name/number translation table and of the code are
passed around in the compile data block. */

compile_block.names_found = 0;
compile_block.name_entry_size = max_name_size + 3;
compile_block.name_table = (uschar *)re + re->name_table_offset;
codestart = compile_block.name_table + re->name_entry_size * re->name_count;
compile_block.start_code = codestart;
compile_block.start_pattern = (const uschar *)pattern;
compile_block.req_varyopt = 0;
compile_block.nopartial = FALSE;

/* Set up a starting, non-extracting bracket, then compile the expression. On
error, *errorptr will be set non-NULL, so we don't need to look at the result
of the function here. */

  ptr = (const uschar *)pattern;
  code = (uschar *)codestart;
  *code = OP_BRA;
  bracount = 0;
  (void)compile_regex(options, options & PCRE_IMS, &bracount, &code, &ptr,
    errorptr, FALSE, 0, &firstbyte, &reqbyte, NULL, &compile_block);
  re->top_bracket = bracount;
  re->top_backref = compile_block.top_backref;


if (compile_block.nopartial) re->options |= PCRE_NOPARTIAL;

/* If not reached end of pattern on success, there's an excess bracket. */

if (*errorptr == NULL && *ptr != 0) *errorptr = ERR22;

/* Fill in the terminating state and check for disastrous overflow, but
if debugging, leave the test till after things are printed out. */

*code++ = OP_END;

#ifndef DEBUG
if (code - codestart > length) *errorptr = ERR23;
#endif

/* Give an error if there's back reference to a non-existent capturing
subpattern. */

if (re->top_backref > re->top_bracket) *errorptr = ERR15;

/* Failed to compile, or error while post-processing */

  if (*errorptr != NULL)
    {
    (pcre_free)(re);
    PCRE_ERROR_RETURN:
    *erroroffset = ptr - (const uschar *)pattern;
    return NULL;
    }


/* If the anchored option was not passed, set the flag if we can determine that
the pattern is anchored by virtue of ^ characters or \A or anything else (such
as starting with .* when DOTALL is set).

Otherwise, if we know what the first character has to be, save it, because that
speeds up unanchored matches no end. If not, see if we can set the
PCRE_STARTLINE flag. This is helpful for multiline matches when all branches
start with ^. and also when all branches start with .* for non-DOTALL matches.
*/

  if ((options & PCRE_ANCHORED) == 0)
    {
    int temp_options = options;
    if (is_anchored(codestart, &temp_options, 0, compile_block.backref_map))
      re->options |= PCRE_ANCHORED;
    else
      {
      if (firstbyte < 0)
        firstbyte = find_firstassertedchar(codestart, &temp_options, FALSE);
      if (firstbyte >= 0)   /* Remove caseless flag for non-caseable chars */
        {
        int ch = firstbyte & 255;
        re->first_byte = ((firstbyte & REQ_CASELESS) != 0 &&
           compile_block.fcc[ch] == ch)? ch : firstbyte;
        re->options |= PCRE_FIRSTSET;
        }
      else if (is_startline(codestart, 0, compile_block.backref_map))
        re->options |= PCRE_STARTLINE;
      }
    }


/* For an anchored pattern, we use the "required byte" only if it follows a
variable length item in the regex. Remove the caseless flag for non-caseable
bytes. */

  if (reqbyte >= 0 &&
       ((re->options & PCRE_ANCHORED) == 0 || (reqbyte & REQ_VARY) != 0))
    {
    int ch = reqbyte & 255;
    re->req_byte = ((reqbyte & REQ_CASELESS) != 0 &&
      compile_block.fcc[ch] == ch)? (reqbyte & ~REQ_CASELESS) : reqbyte;
    re->options |= PCRE_REQCHSET;
    }


/* Print out the compiled data for debugging */

#ifdef DEBUG

  printf("Length = %d top_bracket = %d top_backref = %d\n",
    length, re->top_bracket, re->top_backref);


  if (re->options != 0)
    {
    printf("%s%s%s%s%s%s%s%s%s%s\n",
      ((re->options & PCRE_NOPARTIAL) != 0)? "nopartial " : "",
      ((re->options & PCRE_ANCHORED) != 0)? "anchored " : "",
      ((re->options & PCRE_CASELESS) != 0)? "caseless " : "",
      ((re->options & PCRE_ICHANGED) != 0)? "case state changed " : "",
      ((re->options & PCRE_EXTENDED) != 0)? "extended " : "",
      ((re->options & PCRE_MULTILINE) != 0)? "multiline " : "",
      ((re->options & PCRE_DOTALL) != 0)? "dotall " : "",
      ((re->options & PCRE_DOLLAR_ENDONLY) != 0)? "endonly " : "",
      ((re->options & PCRE_EXTRA) != 0)? "extra " : "",
      ((re->options & PCRE_UNGREEDY) != 0)? "ungreedy " : "");
    }


  if ((re->options & PCRE_FIRSTSET) != 0)
    {
    int ch = re->first_byte & 255;
    const char *caseless = ((re->first_byte & REQ_CASELESS) == 0)? "" : " (caseless)";
    if (isprint(ch)) printf("First char = %c%s\n", ch, caseless);
      else printf("First char = \\x%02x%s\n", ch, caseless);
    }


  if ((re->options & PCRE_REQCHSET) != 0)
    {
    int ch = re->req_byte & 255;
    const char *caseless = ((re->req_byte & REQ_CASELESS) == 0)? "" : " (caseless)";
    if (isprint(ch)) printf("Req char = %c%s\n", ch, caseless);
      else printf("Req char = \\x%02x%s\n", ch, caseless);
    }


print_internals(re, stdout);

/* This check is done here in the debugging case so that the code that
was compiled can be seen. */

  if (code - codestart > length)
    {
    *errorptr = ERR23;
    (pcre_free)(re);
    *erroroffset = ptr - (uschar *)pattern;
    return NULL;
    }
  #endif


return (pcre *)re;
}



  /*************************************************
  *          Match a back-reference                *
  *************************************************/


/* If a back reference hasn't been set, the length that is passed is greater
than the number of characters left in the string, so the match fails.

  Arguments:
    offset      index into the offset vector
    eptr        points into the subject
    length      length to be matched
    md          points to match data block
    ims         the ims flags


  Returns:      TRUE if matched
  */


  static BOOL
  match_ref(int offset, register const uschar *eptr, int length, match_data *md,
    unsigned long int ims)
  {
  const uschar *p = md->start_subject + md->offset_vector[offset];


  #ifdef DEBUG
  if (eptr >= md->end_subject)
    printf("matching subject <null>");
  else
    {
    printf("matching subject ");
    pchars(eptr, length, TRUE, md);
    }
  printf(" against backref ");
  pchars(p, length, FALSE, md);
  printf("\n");
  #endif


/* Always fail if not enough characters left */

if (length > md->end_subject - eptr) return FALSE;

/* Separate the caselesss case for speed */

  if ((ims & PCRE_CASELESS) != 0)
    {
    while (length-- > 0)
      if (md->lcc[*p++] != md->lcc[*eptr++]) return FALSE;
    }
  else
    { while (length-- > 0) if (*p++ != *eptr++) return FALSE; }


return TRUE;
}


  #ifdef SUPPORT_UTF8
  /*************************************************
  *       Match character against an XCLASS        *
  *************************************************/


/* This function is called from within the XCLASS code below, to match a
character against an extended class which might match values > 255.

  Arguments:
    c           the character
    data        points to the flag byte of the XCLASS data


  Returns:      TRUE if character matches, else FALSE
  */


static BOOL
match_xclass(int c, const uschar *data)
{
int t;
BOOL negated = (*data & XCL_NOT) != 0;

/* Character values < 256 are matched against a bitmap, if one is present. If
not, we still carry on, because there may be ranges that start below 256 in the
additional data. */

  if (c < 256)
    {
    if ((*data & XCL_MAP) != 0 && (data[1 + c/8] & (1 << (c&7))) != 0)
      return !negated;   /* char found */
    }


/* First skip the bit map if present. Then match against the list of Unicode
properties or large chars or ranges that end with a large char. We won't ever
encounter XCL_PROP or XCL_NOTPROP when UCP support is not compiled. */

if ((*data++ & XCL_MAP) != 0) data += 32;

  while ((t = *data++) != XCL_END)
    {
    int x, y;
    if (t == XCL_SINGLE)
      {
      GETCHARINC(x, data);
      if (c == x) return !negated;
      }
    else if (t == XCL_RANGE)
      {
      GETCHARINC(x, data);
      GETCHARINC(y, data);
      if (c >= x && c <= y) return !negated;
      }


  #ifdef SUPPORT_UCP
    else  /* XCL_PROP & XCL_NOTPROP */
      {
      int chartype, othercase;
      int rqdtype = *data++;
      int category = ucp_findchar(c, &chartype, &othercase);
      if (rqdtype >= 128)
        {
        if ((rqdtype - 128 == category) == (t == XCL_PROP)) return !negated;
        }
      else
        {
        if ((rqdtype == chartype) == (t == XCL_PROP)) return !negated;
        }
      }
  #endif  /* SUPPORT_UCP */
    }


return negated; /* char did not match */
}
#endif


  /***************************************************************************
  ****************************************************************************
                     RECURSION IN THE match() FUNCTION


The match() function is highly recursive. Some regular expressions can cause
it to recurse thousands of times. I was writing for Unix, so I just let it
call itself recursively. This uses the stack for saving everything that has
to be saved for a recursive call. On Unix, the stack can be large, and this
works fine.

It turns out that on non-Unix systems there are problems with programs that
use a lot of stack. (This despite the fact that every last chip has oodles
of memory these days, and techniques for extending the stack have been known
for decades.) So....

There is a fudge, triggered by defining NO_RECURSE, which avoids recursive
calls by keeping local variables that need to be preserved in blocks of memory
obtained from malloc instead instead of on the stack. Macros are used to
achieve this so that the actual code doesn't look very different to what it
always used to.
****************************************************************************
***************************************************************************/


/* These versions of the macros use the stack, as normal */

#ifndef NO_RECURSE
#define REGISTER register
#define RMATCH(rx,ra,rb,rc,rd,re,rf,rg) rx = match(ra,rb,rc,rd,re,rf,rg)
#define RRETURN(ra) return ra
#else


/* These versions of the macros manage a private stack on the heap. Note
that the rd argument of RMATCH isn't actually used. It's the md argument of
match(), which never changes. */

#define REGISTER

  #define RMATCH(rx,ra,rb,rc,rd,re,rf,rg)\
    {\
    heapframe *newframe = (pcre_stack_malloc)(sizeof(heapframe));\
    if (setjmp(frame->Xwhere) == 0)\
      {\
      newframe->Xeptr = ra;\
      newframe->Xecode = rb;\
      newframe->Xoffset_top = rc;\
      newframe->Xims = re;\
      newframe->Xeptrb = rf;\
      newframe->Xflags = rg;\
      newframe->Xprevframe = frame;\
      frame = newframe;\
      DPRINTF(("restarting from line %d\n", __LINE__));\
      goto HEAP_RECURSE;\
      }\
    else\
      {\
      DPRINTF(("longjumped back to line %d\n", __LINE__));\
      frame = md->thisframe;\
      rx = frame->Xresult;\
      }\
    }


  #define RRETURN(ra)\
    {\
    heapframe *newframe = frame;\
    frame = newframe->Xprevframe;\
    (pcre_stack_free)(newframe);\
    if (frame != NULL)\
      {\
      frame->Xresult = ra;\
      md->thisframe = frame;\
      longjmp(frame->Xwhere, 1);\
      }\
    return ra;\
    }



/* Structure for remembering the local variables in a private frame */

  typedef struct heapframe {
    struct heapframe *Xprevframe;


    /* Function arguments that may change */


    const uschar *Xeptr;
    const uschar *Xecode;
    int Xoffset_top;
    long int Xims;
    eptrblock *Xeptrb;
    int Xflags;


    /* Function local variables */


    const uschar *Xcallpat;
    const uschar *Xcharptr;
    const uschar *Xdata;
    const uschar *Xnext;
    const uschar *Xpp;
    const uschar *Xprev;
    const uschar *Xsaved_eptr;


    recursion_info Xnew_recursive;


    BOOL Xcur_is_word;
    BOOL Xcondition;
    BOOL Xminimize;
    BOOL Xprev_is_word;


    unsigned long int Xoriginal_ims;


  #ifdef SUPPORT_UCP
    int Xprop_type;
    int Xprop_fail_result;
    int Xprop_category;
    int Xprop_chartype;
    int Xprop_othercase;
    int Xprop_test_against;
    int *Xprop_test_variable;
  #endif


    int Xctype;
    int Xfc;
    int Xfi;
    int Xlength;
    int Xmax;
    int Xmin;
    int Xnumber;
    int Xoffset;
    int Xop;
    int Xsave_capture_last;
    int Xsave_offset1, Xsave_offset2, Xsave_offset3;
    int Xstacksave[REC_STACK_SAVE_MAX];


    eptrblock Xnewptrb;


    /* Place to pass back result, and where to jump back to */


    int  Xresult;
    jmp_buf Xwhere;


} heapframe;

#endif


/***************************************************************************
***************************************************************************/



  /*************************************************
  *         Match from current position            *
  *************************************************/


/* On entry ecode points to the first opcode, and eptr to the first character
in the subject string, while eptrb holds the value of eptr at the start of the
last bracketed group - used for breaking infinite loops matching zero-length
strings. This function is called recursively in many circumstances. Whenever it
returns a negative (error) response, the outer incarnation must also return the
same response.

Performance note: It might be tempting to extract commonly used fields from the
md structure (e.g. utf8, end_subject) into individual variables to improve
performance. Tests using gcc on a SPARC disproved this; in the first case, it
made performance worse.

  Arguments:
     eptr        pointer in subject
     ecode       position in code
     offset_top  current top pointer
     md          pointer to "static" info for the match
     ims         current /i, /m, and /s options
     eptrb       pointer to chain of blocks containing eptr at start of
                   brackets - for testing for empty matches
     flags       can contain
                   match_condassert - this is an assertion condition
                   match_isgroup - this is the start of a bracketed group


  Returns:       MATCH_MATCH if matched            )  these values are >= 0
                 MATCH_NOMATCH if failed to match  )
                 a negative PCRE_ERROR_xxx value if aborted by an error condition
                   (e.g. stopped by recursion limit)
  */


  static int
  match(REGISTER const uschar *eptr, REGISTER const uschar *ecode,
    int offset_top, match_data *md, unsigned long int ims, eptrblock *eptrb,
    int flags)
  {
  /* These variables do not need to be preserved over recursion in this function,
  so they can be ordinary variables in all cases. Mark them with "register"
  because they are used a lot in loops. */


  register int rrc;    /* Returns from recursive calls */
  register int i;      /* Used for loops not involving calls to RMATCH() */
  register int c;      /* Character values not kept over RMATCH() calls */


/* When recursion is not being used, all "local" variables that have to be
preserved over calls to RMATCH() are part of a "frame" which is obtained from
heap storage. Set up the top-level frame here; others are obtained from the
heap whenever RMATCH() does a "recursion". See the macro definitions above. */

  #ifdef NO_RECURSE
  heapframe *frame = (pcre_stack_malloc)(sizeof(heapframe));
  frame->Xprevframe = NULL;            /* Marks the top level */


/* Copy in the original argument variables */

frame->Xeptr = eptr;
frame->Xecode = ecode;
frame->Xoffset_top = offset_top;
frame->Xims = ims;
frame->Xeptrb = eptrb;
frame->Xflags = flags;

/* This is where control jumps back to to effect "recursion" */

HEAP_RECURSE:

/* Macros make the argument variables come from the current frame */

  #define eptr               frame->Xeptr
  #define ecode              frame->Xecode
  #define offset_top         frame->Xoffset_top
  #define ims                frame->Xims
  #define eptrb              frame->Xeptrb
  #define flags              frame->Xflags


/* Ditto for the local variables */

  #ifdef SUPPORT_UTF8
  #define charptr            frame->Xcharptr
  #endif
  #define callpat            frame->Xcallpat
  #define data               frame->Xdata
  #define next               frame->Xnext
  #define pp                 frame->Xpp
  #define prev               frame->Xprev
  #define saved_eptr         frame->Xsaved_eptr


  #define new_recursive      frame->Xnew_recursive


  #define cur_is_word        frame->Xcur_is_word
  #define condition          frame->Xcondition
  #define minimize           frame->Xminimize
  #define prev_is_word       frame->Xprev_is_word


  #define original_ims       frame->Xoriginal_ims


  #ifdef SUPPORT_UCP
  #define prop_type          frame->Xprop_type
  #define prop_fail_result   frame->Xprop_fail_result
  #define prop_category      frame->Xprop_category
  #define prop_chartype      frame->Xprop_chartype
  #define prop_othercase     frame->Xprop_othercase
  #define prop_test_against  frame->Xprop_test_against
  #define prop_test_variable frame->Xprop_test_variable
  #endif


  #define ctype              frame->Xctype
  #define fc                 frame->Xfc
  #define fi                 frame->Xfi
  #define length             frame->Xlength
  #define max                frame->Xmax
  #define min                frame->Xmin
  #define number             frame->Xnumber
  #define offset             frame->Xoffset
  #define op                 frame->Xop
  #define save_capture_last  frame->Xsave_capture_last
  #define save_offset1       frame->Xsave_offset1
  #define save_offset2       frame->Xsave_offset2
  #define save_offset3       frame->Xsave_offset3
  #define stacksave          frame->Xstacksave


  #define newptrb            frame->Xnewptrb


/* When recursion is being used, local variables are allocated on the stack and
get preserved during recursion in the normal way. In this environment, fi and
i, and fc and c, can be the same variables. */

#else
#define fi i
#define fc c


  #ifdef SUPPORT_UTF8                /* Many of these variables are used ony */
  const uschar *charptr;             /* small blocks of the code. My normal  */
  #endif                             /* style of coding would have declared  */
  const uschar *callpat;             /* them within each of those blocks.    */
  const uschar *data;                /* However, in order to accommodate the */
  const uschar *next;                /* version of this code that uses an    */
  const uschar *pp;                  /* external "stack" implemented on the  */
  const uschar *prev;                /* heap, it is easier to declare them   */
  const uschar *saved_eptr;          /* all here, so the declarations can    */
                                     /* be cut out in a block. The only      */
  recursion_info new_recursive;      /* declarations within blocks below are */
                                     /* for variables that do not have to    */
  BOOL cur_is_word;                  /* be preserved over a recursive call   */
  BOOL condition;                    /* to RMATCH().                         */
  BOOL minimize;
  BOOL prev_is_word;


unsigned long int original_ims;

#ifdef SUPPORT_UCP
int prop_type;
int prop_fail_result;
int prop_category;
int prop_chartype;
int prop_othercase;
int prop_test_against;
int *prop_test_variable;
#endif

int ctype;
int length;
int max;
int min;
int number;
int offset;
int op;
int save_capture_last;
int save_offset1, save_offset2, save_offset3;
int stacksave[REC_STACK_SAVE_MAX];

eptrblock newptrb;
#endif

/* These statements are here to stop the compiler complaining about unitialized
variables. */

#ifdef SUPPORT_UCP
prop_fail_result = 0;
prop_test_against = 0;
prop_test_variable = NULL;
#endif

/* OK, now we can get on with the real code of the function. Recursion is
specified by the macros RMATCH and RRETURN. When NO_RECURSE is *not* defined,
these just turn into a recursive call to match() and a "return", respectively.
However, RMATCH isn't like a function call because it's quite a complicated
macro. It has to be used in one particular way. This shouldn't, however, impact
performance when true recursion is being used. */

if (md->match_call_count++ >= md->match_limit) RRETURN(PCRE_ERROR_MATCHLIMIT);

  original_ims = ims;    /* Save for resetting on ')' */


/* At the start of a bracketed group, add the current subject pointer to the
stack of such pointers, to be re-instated at the end of the group when we hit
the closing ket. When match() is called in other circumstances, we don't add to
this stack. */

  if ((flags & match_isgroup) != 0)
    {
    newptrb.epb_prev = eptrb;
    newptrb.epb_saved_eptr = eptr;
    eptrb = &newptrb;
    }


/* Now start processing the operations. */

  for (;;)
    {
    op = *ecode;
    minimize = FALSE;


    /* For partial matching, remember if we ever hit the end of the subject after
    matching at least one subject character. */


    if (md->partial &&
        eptr >= md->end_subject &&
        eptr > md->start_match)
      md->hitend = TRUE;


    /* Opening capturing bracket. If there is space in the offset vector, save
    the current subject position in the working slot at the top of the vector. We
    mustn't change the current values of the data slot, because they may be set
    from a previous iteration of this group, and be referred to by a reference
    inside the group.


    If the bracket fails to match, we need to restore this value and also the
    values of the final offsets, in case they were set by a previous iteration of
    the same bracket.


    If there isn't enough space in the offset vector, treat this as if it were a
    non-capturing bracket. Don't worry about setting the flag for the error case
    here; that is handled in the code for KET. */


    if (op > OP_BRA)
      {
      number = op - OP_BRA;


      /* For extended extraction brackets (large number), we have to fish out the
      number from a dummy opcode at the start. */


      if (number > EXTRACT_BASIC_MAX)
        number = GET2(ecode, 2+LINK_SIZE);
      offset = number << 1;


  #ifdef DEBUG
      printf("start bracket %d subject=", number);
      pchars(eptr, 16, TRUE, md);
      printf("\n");
  #endif


      if (offset < md->offset_max)
        {
        save_offset1 = md->offset_vector[offset];
        save_offset2 = md->offset_vector[offset+1];
        save_offset3 = md->offset_vector[md->offset_end - number];
        save_capture_last = md->capture_last;


        DPRINTF(("saving %d %d %d\n", save_offset1, save_offset2, save_offset3));
        md->offset_vector[md->offset_end - number] = eptr - md->start_subject;


        do
          {
          RMATCH(rrc, eptr, ecode + 1 + LINK_SIZE, offset_top, md, ims, eptrb,
            match_isgroup);
          if (rrc != MATCH_NOMATCH) RRETURN(rrc);
          md->capture_last = save_capture_last;
          ecode += GET(ecode, 1);
          }
        while (*ecode == OP_ALT);


        DPRINTF(("bracket %d failed\n", number));


        md->offset_vector[offset] = save_offset1;
        md->offset_vector[offset+1] = save_offset2;
        md->offset_vector[md->offset_end - number] = save_offset3;


        RRETURN(MATCH_NOMATCH);
        }


      /* Insufficient room for saving captured contents */


      else op = OP_BRA;
      }


    /* Other types of node can be handled by a switch */


    switch(op)
      {
      case OP_BRA:     /* Non-capturing bracket: optimized */
      DPRINTF(("start bracket 0\n"));
      do
        {
        RMATCH(rrc, eptr, ecode + 1 + LINK_SIZE, offset_top, md, ims, eptrb,
          match_isgroup);
        if (rrc != MATCH_NOMATCH) RRETURN(rrc);
        ecode += GET(ecode, 1);
        }
      while (*ecode == OP_ALT);
      DPRINTF(("bracket 0 failed\n"));
      RRETURN(MATCH_NOMATCH);


      /* Conditional group: compilation checked that there are no more than
      two branches. If the condition is false, skipping the first branch takes us
      past the end if there is only one branch, but that's OK because that is
      exactly what going to the ket would do. */


      case OP_COND:
      if (ecode[LINK_SIZE+1] == OP_CREF) /* Condition extract or recurse test */
        {
        offset = GET2(ecode, LINK_SIZE+2) << 1;  /* Doubled ref number */
        condition = (offset == CREF_RECURSE * 2)?
          (md->recursive != NULL) :
          (offset < offset_top && md->offset_vector[offset] >= 0);
        RMATCH(rrc, eptr, ecode + (condition?
          (LINK_SIZE + 4) : (LINK_SIZE + 1 + GET(ecode, 1))),
          offset_top, md, ims, eptrb, match_isgroup);
        RRETURN(rrc);
        }


      /* The condition is an assertion. Call match() to evaluate it - setting
      the final argument TRUE causes it to stop at the end of an assertion. */


      else
        {
        RMATCH(rrc, eptr, ecode + 1 + LINK_SIZE, offset_top, md, ims, NULL,
            match_condassert | match_isgroup);
        if (rrc == MATCH_MATCH)
          {
          ecode += 1 + LINK_SIZE + GET(ecode, LINK_SIZE+2);
          while (*ecode == OP_ALT) ecode += GET(ecode, 1);
          }
        else if (rrc != MATCH_NOMATCH)
          {
          RRETURN(rrc);         /* Need braces because of following else */
          }
        else ecode += GET(ecode, 1);
        RMATCH(rrc, eptr, ecode + 1 + LINK_SIZE, offset_top, md, ims, eptrb,
          match_isgroup);
        RRETURN(rrc);
        }
      /* Control never reaches here */


      /* Skip over conditional reference or large extraction number data if
      encountered. */


      case OP_CREF:
      case OP_BRANUMBER:
      ecode += 3;
      break;


      /* End of the pattern. If we are in a recursion, we should restore the
      offsets appropriately and continue from after the call. */


      case OP_END:
      if (md->recursive != NULL && md->recursive->group_num == 0)
        {
        recursion_info *rec = md->recursive;
        DPRINTF(("Hit the end in a (?0) recursion\n"));
        md->recursive = rec->prevrec;
        memmove(md->offset_vector, rec->offset_save,
          rec->saved_max * sizeof(int));
        md->start_match = rec->save_start;
        ims = original_ims;
        ecode = rec->after_call;
        break;
        }


      /* Otherwise, if PCRE_NOTEMPTY is set, fail if we have matched an empty
      string - backtracking will then try other alternatives, if any. */


      if (md->notempty && eptr == md->start_match) RRETURN(MATCH_NOMATCH);
      md->end_match_ptr = eptr;          /* Record where we ended */
      md->end_offset_top = offset_top;   /* and how many extracts were taken */
      RRETURN(MATCH_MATCH);


      /* Change option settings */


      case OP_OPT:
      ims = ecode[1];
      ecode += 2;
      DPRINTF(("ims set to %02lx\n", ims));
      break;


      /* Assertion brackets. Check the alternative branches in turn - the
      matching won't pass the KET for an assertion. If any one branch matches,
      the assertion is true. Lookbehind assertions have an OP_REVERSE item at the
      start of each branch to move the current point backwards, so the code at
      this level is identical to the lookahead case. */


      case OP_ASSERT:
      case OP_ASSERTBACK:
      do
        {
        RMATCH(rrc, eptr, ecode + 1 + LINK_SIZE, offset_top, md, ims, NULL,
          match_isgroup);
        if (rrc == MATCH_MATCH) break;
        if (rrc != MATCH_NOMATCH) RRETURN(rrc);
        ecode += GET(ecode, 1);
        }
      while (*ecode == OP_ALT);
      if (*ecode == OP_KET) RRETURN(MATCH_NOMATCH);


      /* If checking an assertion for a condition, return MATCH_MATCH. */


      if ((flags & match_condassert) != 0) RRETURN(MATCH_MATCH);


      /* Continue from after the assertion, updating the offsets high water
      mark, since extracts may have been taken during the assertion. */


      do ecode += GET(ecode,1); while (*ecode == OP_ALT);
      ecode += 1 + LINK_SIZE;
      offset_top = md->end_offset_top;
      continue;


      /* Negative assertion: all branches must fail to match */


      case OP_ASSERT_NOT:
      case OP_ASSERTBACK_NOT:
      do
        {
        RMATCH(rrc, eptr, ecode + 1 + LINK_SIZE, offset_top, md, ims, NULL,
          match_isgroup);
        if (rrc == MATCH_MATCH) RRETURN(MATCH_NOMATCH);
        if (rrc != MATCH_NOMATCH) RRETURN(rrc);
        ecode += GET(ecode,1);
        }
      while (*ecode == OP_ALT);


      if ((flags & match_condassert) != 0) RRETURN(MATCH_MATCH);


      ecode += 1 + LINK_SIZE;
      continue;


      /* Move the subject pointer back. This occurs only at the start of
      each branch of a lookbehind assertion. If we are too close to the start to
      move back, this match function fails. When working with UTF-8 we move
      back a number of characters, not bytes. */


      case OP_REVERSE:
  #ifdef SUPPORT_UTF8
      if (md->utf8)
        {
        c = GET(ecode,1);
        for (i = 0; i < c; i++)
          {
          eptr--;
          if (eptr < md->start_subject) RRETURN(MATCH_NOMATCH);
          BACKCHAR(eptr)
          }
        }
      else
  #endif


      /* No UTF-8 support, or not in UTF-8 mode: count is byte count */


        {
        eptr -= GET(ecode,1);
        if (eptr < md->start_subject) RRETURN(MATCH_NOMATCH);
        }


      /* Skip to next op code */


      ecode += 1 + LINK_SIZE;
      break;


      /* The callout item calls an external function, if one is provided, passing
      details of the match so far. This is mainly for debugging, though the
      function is able to force a failure. */


      case OP_CALLOUT:
      if (pcre_callout != NULL)
        {
        pcre_callout_block cb;
        cb.version          = 1;   /* Version 1 of the callout block */
        cb.callout_number   = ecode[1];
        cb.offset_vector    = md->offset_vector;
        cb.subject          = (const char *)md->start_subject;
        cb.subject_length   = md->end_subject - md->start_subject;
        cb.start_match      = md->start_match - md->start_subject;
        cb.current_position = eptr - md->start_subject;
        cb.pattern_position = GET(ecode, 2);
        cb.next_item_length = GET(ecode, 2 + LINK_SIZE);
        cb.capture_top      = offset_top/2;
        cb.capture_last     = md->capture_last;
        cb.callout_data     = md->callout_data;
        if ((rrc = (*pcre_callout)(&cb)) > 0) RRETURN(MATCH_NOMATCH);
        if (rrc < 0) RRETURN(rrc);
        }
      ecode += 2 + 2*LINK_SIZE;
      break;


      /* Recursion either matches the current regex, or some subexpression. The
      offset data is the offset to the starting bracket from the start of the
      whole pattern. (This is so that it works from duplicated subpatterns.)


      If there are any capturing brackets started but not finished, we have to
      save their starting points and reinstate them after the recursion. However,
      we don't know how many such there are (offset_top records the completed
      total) so we just have to save all the potential data. There may be up to
      65535 such values, which is too large to put on the stack, but using malloc
      for small numbers seems expensive. As a compromise, the stack is used when
      there are no more than REC_STACK_SAVE_MAX values to store; otherwise malloc
      is used. A problem is what to do if the malloc fails ... there is no way of
      returning to the top level with an error. Save the top REC_STACK_SAVE_MAX
      values on the stack, and accept that the rest may be wrong.


      There are also other values that have to be saved. We use a chained
      sequence of blocks that actually live on the stack. Thanks to Robin Houston
      for the original version of this logic. */


      case OP_RECURSE:
        {
        callpat = md->start_code + GET(ecode, 1);
        new_recursive.group_num = *callpat - OP_BRA;


        /* For extended extraction brackets (large number), we have to fish out
        the number from a dummy opcode at the start. */


        if (new_recursive.group_num > EXTRACT_BASIC_MAX)
          new_recursive.group_num = GET2(callpat, 2+LINK_SIZE);


        /* Add to "recursing stack" */


        new_recursive.prevrec = md->recursive;
        md->recursive = &new_recursive;


        /* Find where to continue from afterwards */


        ecode += 1 + LINK_SIZE;
        new_recursive.after_call = ecode;


        /* Now save the offset data. */


        new_recursive.saved_max = md->offset_end;
        if (new_recursive.saved_max <= REC_STACK_SAVE_MAX)
          new_recursive.offset_save = stacksave;
        else
          {
          new_recursive.offset_save =
            (int *)(pcre_malloc)(new_recursive.saved_max * sizeof(int));
          if (new_recursive.offset_save == NULL) RRETURN(PCRE_ERROR_NOMEMORY);
          }


        memcpy(new_recursive.offset_save, md->offset_vector,
              new_recursive.saved_max * sizeof(int));
        new_recursive.save_start = md->start_match;
        md->start_match = eptr;


        /* OK, now we can do the recursion. For each top-level alternative we
        restore the offset and recursion data. */


        DPRINTF(("Recursing into group %d\n", new_recursive.group_num));
        do
          {
          RMATCH(rrc, eptr, callpat + 1 + LINK_SIZE, offset_top, md, ims,
              eptrb, match_isgroup);
          if (rrc == MATCH_MATCH)
            {
            md->recursive = new_recursive.prevrec;
            if (new_recursive.offset_save != stacksave)
              (pcre_free)(new_recursive.offset_save);
            RRETURN(MATCH_MATCH);
            }
          else if (rrc != MATCH_NOMATCH) RRETURN(rrc);


          md->recursive = &new_recursive;
          memcpy(md->offset_vector, new_recursive.offset_save,
              new_recursive.saved_max * sizeof(int));
          callpat += GET(callpat, 1);
          }
        while (*callpat == OP_ALT);


        DPRINTF(("Recursion didn't match\n"));
        md->recursive = new_recursive.prevrec;
        if (new_recursive.offset_save != stacksave)
          (pcre_free)(new_recursive.offset_save);
        RRETURN(MATCH_NOMATCH);
        }
      /* Control never reaches here */


      /* "Once" brackets are like assertion brackets except that after a match,
      the point in the subject string is not moved back. Thus there can never be
      a move back into the brackets. Friedl calls these "atomic" subpatterns.
      Check the alternative branches in turn - the matching won't pass the KET
      for this kind of subpattern. If any one branch matches, we carry on as at
      the end of a normal bracket, leaving the subject pointer. */


      case OP_ONCE:
        {
        prev = ecode;
        saved_eptr = eptr;


        do
          {
          RMATCH(rrc, eptr, ecode + 1 + LINK_SIZE, offset_top, md, ims,
            eptrb, match_isgroup);
          if (rrc == MATCH_MATCH) break;
          if (rrc != MATCH_NOMATCH) RRETURN(rrc);
          ecode += GET(ecode,1);
          }
        while (*ecode == OP_ALT);


        /* If hit the end of the group (which could be repeated), fail */


        if (*ecode != OP_ONCE && *ecode != OP_ALT) RRETURN(MATCH_NOMATCH);


        /* Continue as from after the assertion, updating the offsets high water
        mark, since extracts may have been taken. */


        do ecode += GET(ecode,1); while (*ecode == OP_ALT);


        offset_top = md->end_offset_top;
        eptr = md->end_match_ptr;


        /* For a non-repeating ket, just continue at this level. This also
        happens for a repeating ket if no characters were matched in the group.
        This is the forcible breaking of infinite loops as implemented in Perl
        5.005. If there is an options reset, it will get obeyed in the normal
        course of events. */


        if (*ecode == OP_KET || eptr == saved_eptr)
          {
          ecode += 1+LINK_SIZE;
          break;
          }


        /* The repeating kets try the rest of the pattern or restart from the
        preceding bracket, in the appropriate order. We need to reset any options
        that changed within the bracket before re-running it, so check the next
        opcode. */


        if (ecode[1+LINK_SIZE] == OP_OPT)
          {
          ims = (ims & ~PCRE_IMS) | ecode[4];
          DPRINTF(("ims set to %02lx at group repeat\n", ims));
          }


        if (*ecode == OP_KETRMIN)
          {
          RMATCH(rrc, eptr, ecode + 1 + LINK_SIZE, offset_top, md, ims, eptrb, 0);
          if (rrc != MATCH_NOMATCH) RRETURN(rrc);
          RMATCH(rrc, eptr, prev, offset_top, md, ims, eptrb, match_isgroup);
          if (rrc != MATCH_NOMATCH) RRETURN(rrc);
          }
        else  /* OP_KETRMAX */
          {
          RMATCH(rrc, eptr, prev, offset_top, md, ims, eptrb, match_isgroup);
          if (rrc != MATCH_NOMATCH) RRETURN(rrc);
          RMATCH(rrc, eptr, ecode + 1+LINK_SIZE, offset_top, md, ims, eptrb, 0);
          if (rrc != MATCH_NOMATCH) RRETURN(rrc);
          }
        }
      RRETURN(MATCH_NOMATCH);


      /* An alternation is the end of a branch; scan along to find the end of the
      bracketed group and go to there. */


      case OP_ALT:
      do ecode += GET(ecode,1); while (*ecode == OP_ALT);
      break;


      /* BRAZERO and BRAMINZERO occur just before a bracket group, indicating
      that it may occur zero times. It may repeat infinitely, or not at all -
      i.e. it could be ()* or ()? in the pattern. Brackets with fixed upper
      repeat limits are compiled as a number of copies, with the optional ones
      preceded by BRAZERO or BRAMINZERO. */


      case OP_BRAZERO:
        {
        next = ecode+1;
        RMATCH(rrc, eptr, next, offset_top, md, ims, eptrb, match_isgroup);
        if (rrc != MATCH_NOMATCH) RRETURN(rrc);
        do next += GET(next,1); while (*next == OP_ALT);
        ecode = next + 1+LINK_SIZE;
        }
      break;


      case OP_BRAMINZERO:
        {
        next = ecode+1;
        do next += GET(next,1); while (*next == OP_ALT);
        RMATCH(rrc, eptr, next + 1+LINK_SIZE, offset_top, md, ims, eptrb,
          match_isgroup);
        if (rrc != MATCH_NOMATCH) RRETURN(rrc);
        ecode++;
        }
      break;


      /* End of a group, repeated or non-repeating. If we are at the end of
      an assertion "group", stop matching and return MATCH_MATCH, but record the
      current high water mark for use by positive assertions. Do this also
      for the "once" (not-backup up) groups. */


      case OP_KET:
      case OP_KETRMIN:
      case OP_KETRMAX:
        {
        prev = ecode - GET(ecode, 1);
        saved_eptr = eptrb->epb_saved_eptr;


        /* Back up the stack of bracket start pointers. */


        eptrb = eptrb->epb_prev;


        if (*prev == OP_ASSERT || *prev == OP_ASSERT_NOT ||
            *prev == OP_ASSERTBACK || *prev == OP_ASSERTBACK_NOT ||
            *prev == OP_ONCE)
          {
          md->end_match_ptr = eptr;      /* For ONCE */
          md->end_offset_top = offset_top;
          RRETURN(MATCH_MATCH);
          }


        /* In all other cases except a conditional group we have to check the
        group number back at the start and if necessary complete handling an
        extraction by setting the offsets and bumping the high water mark. */


        if (*prev != OP_COND)
          {
          number = *prev - OP_BRA;


          /* For extended extraction brackets (large number), we have to fish out
          the number from a dummy opcode at the start. */


          if (number > EXTRACT_BASIC_MAX) number = GET2(prev, 2+LINK_SIZE);
          offset = number << 1;


  #ifdef DEBUG
          printf("end bracket %d", number);
          printf("\n");
  #endif


          /* Test for a numbered group. This includes groups called as a result
          of recursion. Note that whole-pattern recursion is coded as a recurse
          into group 0, so it won't be picked up here. Instead, we catch it when
          the OP_END is reached. */


          if (number > 0)
            {
            md->capture_last = number;
            if (offset >= md->offset_max) md->offset_overflow = TRUE; else
              {
              md->offset_vector[offset] =
                md->offset_vector[md->offset_end - number];
              md->offset_vector[offset+1] = eptr - md->start_subject;
              if (offset_top <= offset) offset_top = offset + 2;
              }


            /* Handle a recursively called group. Restore the offsets
            appropriately and continue from after the call. */


            if (md->recursive != NULL && md->recursive->group_num == number)
              {
              recursion_info *rec = md->recursive;
              DPRINTF(("Recursion (%d) succeeded - continuing\n", number));
              md->recursive = rec->prevrec;
              md->start_match = rec->save_start;
              memcpy(md->offset_vector, rec->offset_save,
                rec->saved_max * sizeof(int));
              ecode = rec->after_call;
              ims = original_ims;
              break;
              }
            }
          }


        /* Reset the value of the ims flags, in case they got changed during
        the group. */


        ims = original_ims;
        DPRINTF(("ims reset to %02lx\n", ims));


        /* For a non-repeating ket, just continue at this level. This also
        happens for a repeating ket if no characters were matched in the group.
        This is the forcible breaking of infinite loops as implemented in Perl
        5.005. If there is an options reset, it will get obeyed in the normal
        course of events. */


        if (*ecode == OP_KET || eptr == saved_eptr)
          {
          ecode += 1 + LINK_SIZE;
          break;
          }


        /* The repeating kets try the rest of the pattern or restart from the
        preceding bracket, in the appropriate order. */


        if (*ecode == OP_KETRMIN)
          {
          RMATCH(rrc, eptr, ecode + 1+LINK_SIZE, offset_top, md, ims, eptrb, 0);
          if (rrc != MATCH_NOMATCH) RRETURN(rrc);
          RMATCH(rrc, eptr, prev, offset_top, md, ims, eptrb, match_isgroup);
          if (rrc != MATCH_NOMATCH) RRETURN(rrc);
          }
        else  /* OP_KETRMAX */
          {
          RMATCH(rrc, eptr, prev, offset_top, md, ims, eptrb, match_isgroup);
          if (rrc != MATCH_NOMATCH) RRETURN(rrc);
          RMATCH(rrc, eptr, ecode + 1+LINK_SIZE, offset_top, md, ims, eptrb, 0);
          if (rrc != MATCH_NOMATCH) RRETURN(rrc);
          }
        }


      RRETURN(MATCH_NOMATCH);


      /* Start of subject unless notbol, or after internal newline if multiline */


      case OP_CIRC:
      if (md->notbol && eptr == md->start_subject) RRETURN(MATCH_NOMATCH);
      if ((ims & PCRE_MULTILINE) != 0)
        {
        if (eptr != md->start_subject && eptr[-1] != NEWLINE)
          RRETURN(MATCH_NOMATCH);
        ecode++;
        break;
        }
      /* ... else fall through */


      /* Start of subject assertion */


      case OP_SOD:
      if (eptr != md->start_subject) RRETURN(MATCH_NOMATCH);
      ecode++;
      break;


      /* Start of match assertion */


      case OP_SOM:
      if (eptr != md->start_subject + md->start_offset) RRETURN(MATCH_NOMATCH);
      ecode++;
      break;


      /* Assert before internal newline if multiline, or before a terminating
      newline unless endonly is set, else end of subject unless noteol is set. */


      case OP_DOLL:
      if ((ims & PCRE_MULTILINE) != 0)
        {
        if (eptr < md->end_subject)
          { if (*eptr != NEWLINE) RRETURN(MATCH_NOMATCH); }
        else
          { if (md->noteol) RRETURN(MATCH_NOMATCH); }
        ecode++;
        break;
        }
      else
        {
        if (md->noteol) RRETURN(MATCH_NOMATCH);
        if (!md->endonly)
          {
          if (eptr < md->end_subject - 1 ||
             (eptr == md->end_subject - 1 && *eptr != NEWLINE))
            RRETURN(MATCH_NOMATCH);
          ecode++;
          break;
          }
        }
      /* ... else fall through */


      /* End of subject assertion (\z) */


----------------------------------------------
Diff block truncated. (Max lines = 10000)
----------------------------------------------