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diff --git a/srclib/pcre/ChangeLog b/srclib/pcre/ChangeLog deleted file mode 100644 index 266cb18cea..0000000000 --- a/srclib/pcre/ChangeLog +++ /dev/null @@ -1,1650 +0,0 @@ -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@pcreposix.dll.a \ - to - -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.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 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 3.2 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. - -**** |