changelog

php-4.4.7学习linux时下载的源代码

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@[e-mail].a \
    to
        -Wl,--out-implib,.libs/@[e-mail].a \

    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 m