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diff --git a/crawl-ref/source/util/pcre/ChangeLog b/crawl-ref/source/util/pcre/ChangeLog deleted file mode 100644 index 88c69f93eb..0000000000 --- a/crawl-ref/source/util/pcre/ChangeLog +++ /dev/null @@ -1,3308 +0,0 @@ -ChangeLog for PCRE ------------------- - -Version 7.7 07-May-08 ---------------------- - -1. Applied Craig's patch to sort out a long long problem: "If we can't convert - a string to a long long, pretend we don't even have a long long." This is - done by checking for the strtoq, strtoll, and _strtoi64 functions. - -2. Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with - pre-7.6 versions, which defined a global no_arg variable instead of putting - it in the RE class. (See also #8 below.) - -3. Remove a line of dead code, identified by coverity and reported by Nuno - Lopes. - -4. Fixed two related pcregrep bugs involving -r with --include or --exclude: - - (1) The include/exclude patterns were being applied to the whole pathnames - of files, instead of just to the final components. - - (2) If there was more than one level of directory, the subdirectories were - skipped unless they satisfied the include/exclude conditions. This is - inconsistent with GNU grep (and could even be seen as contrary to the - pcregrep specification - which I improved to make it absolutely clear). - The action now is always to scan all levels of directory, and just - apply the include/exclude patterns to regular files. - -5. Added the --include_dir and --exclude_dir patterns to pcregrep, and used - --exclude_dir in the tests to avoid scanning .svn directories. - -6. Applied Craig's patch to the QuoteMeta function so that it escapes the - NUL character as backslash + 0 rather than backslash + NUL, because PCRE - doesn't support NULs in patterns. - -7. Added some missing "const"s to declarations of static tables in - pcre_compile.c and pcre_dfa_exec.c. - -8. Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was - caused by fix #2 above. (Subsequently also a second patch to fix the - first patch. And a third patch - this was a messy problem.) - -9. Applied Craig's patch to remove the use of push_back(). - -10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX - matching function regexec(). - -11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n', - which, however, unlike Perl's \g{...}, are subroutine calls, not back - references. PCRE supports relative numbers with this syntax (I don't think - Oniguruma does). - -12. Previously, a group with a zero repeat such as (...){0} was completely - omitted from the compiled regex. However, this means that if the group - was called as a subroutine from elsewhere in the pattern, things went wrong - (an internal error was given). Such groups are now left in the compiled - pattern, with a new opcode that causes them to be skipped at execution - time. - -13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes - to the way PCRE behaves: - - (a) A lone ] character is dis-allowed (Perl treats it as data). - - (b) A back reference to an unmatched subpattern matches an empty string - (Perl fails the current match path). - - (c) A data ] in a character class must be notated as \] because if the - first data character in a class is ], it defines an empty class. (In - Perl it is not possible to have an empty class.) The empty class [] - never matches; it forces failure and is equivalent to (*FAIL) or (?!). - The negative empty class [^] matches any one character, independently - of the DOTALL setting. - -14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a - non-existent subpattern following a character class starting with ']' and - containing () gave an internal compiling error instead of "reference to - non-existent subpattern". Fortunately, when the pattern did exist, the - compiled code was correct. (When scanning forwards to check for the - existencd of the subpattern, it was treating the data ']' as terminating - the class, so got the count wrong. When actually compiling, the reference - was subsequently set up correctly.) - -15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile; - it was being rejected as not supported by pcre_dfa_exec(), even though - other assertions are supported. I have made pcre_dfa_exec() support - (*FAIL). - -16. The implementation of 13c above involved the invention of a new opcode, - OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s - cannot be changed at match time, I realized I could make a small - improvement to matching performance by compiling OP_ALLANY instead of - OP_ANY for "." when DOTALL was set, and then removing the runtime tests - on the OP_ANY path. - -17. Compiling pcretest on Windows with readline support failed without the - following two fixes: (1) Make the unistd.h include conditional on - HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno. - -18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the - ncurses library to be included for pcretest when ReadLine support is - requested, but also to allow for it to be overridden. This patch came from - Daniel Bergström. - -19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined - as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused - any errors with the current Unicode tables. Thanks to Peter Kankowski for - spotting this. - - -Version 7.6 28-Jan-08 ---------------------- - -1. A character class containing a very large number of characters with - codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer - overflow. - -2. Patch to cut out the "long long" test in pcrecpp_unittest when - HAVE_LONG_LONG is not defined. - -3. Applied Christian Ehrlicher's patch to update the CMake build files to - bring them up to date and include new features. This patch includes: - - - Fixed PH's badly added libz and libbz2 support. - - Fixed a problem with static linking. - - Added pcredemo. [But later removed - see 7 below.] - - Fixed dftables problem and added an option. - - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and - HAVE_LONG_LONG. - - Added readline support for pcretest. - - Added an listing of the option settings after cmake has run. - -4. A user submitted a patch to Makefile that makes it easy to create - "pcre.dll" under mingw when using Configure/Make. I added stuff to - Makefile.am that cause it to include this special target, without - affecting anything else. Note that the same mingw target plus all - the other distribution libraries and programs are now supported - when configuring with CMake (see 6 below) instead of with - Configure/Make. - -5. Applied Craig's patch that moves no_arg into the RE class in the C++ code. - This is an attempt to solve the reported problem "pcrecpp::no_arg is not - exported in the Windows port". It has not yet been confirmed that the patch - solves the problem, but it does no harm. - -6. Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and - NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured - with CMake, and also correct the comment about stack recursion. - -7. Remove the automatic building of pcredemo from the ./configure system and - from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example - of a program that users should build themselves after PCRE is installed, so - building it automatically is not really right. What is more, it gave - trouble in some build environments. - -8. Further tidies to CMakeLists.txt from Sheri and Christian. - - -Version 7.5 10-Jan-08 ---------------------- - -1. Applied a patch from Craig: "This patch makes it possible to 'ignore' - values in parens when parsing an RE using the C++ wrapper." - -2. Negative specials like \S did not work in character classes in UTF-8 mode. - Characters greater than 255 were excluded from the class instead of being - included. - -3. The same bug as (2) above applied to negated POSIX classes such as - [:^space:]. - -4. PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it - defined or documented. It seems to have been a typo for PCRE_STATIC, so - I have changed it. - -5. The construct (?&) was not diagnosed as a syntax error (it referenced the - first named subpattern) and a construct such as (?&a) would reference the - first named subpattern whose name started with "a" (in other words, the - length check was missing). Both these problems are fixed. "Subpattern name - expected" is now given for (?&) (a zero-length name), and this patch also - makes it give the same error for \k'' (previously it complained that that - was a reference to a non-existent subpattern). - -6. The erroneous patterns (?+-a) and (?-+a) give different error messages; - this is right because (?- can be followed by option settings as well as by - digits. I have, however, made the messages clearer. - -7. Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns - than the number used in the conditional) now cause a compile-time error. - This is actually not compatible with Perl, which accepts such patterns, but - treats the conditional as always being FALSE (as PCRE used to), but it - seems to me that giving a diagnostic is better. - -8. Change "alphameric" to the more common word "alphanumeric" in comments - and messages. - -9. Fix two occurrences of "backslash" in comments that should have been - "backspace". - -10. Remove two redundant lines of code that can never be obeyed (their function - was moved elsewhere). - -11. The program that makes PCRE's Unicode character property table had a bug - which caused it to generate incorrect table entries for sequences of - characters that have the same character type, but are in different scripts. - It amalgamated them into a single range, with the script of the first of - them. In other words, some characters were in the wrong script. There were - thirteen such cases, affecting characters in the following ranges: - - U+002b0 - U+002c1 - U+0060c - U+0060d - U+0061e - U+00612 - U+0064b - U+0065e - U+0074d - U+0076d - U+01800 - U+01805 - U+01d00 - U+01d77 - U+01d9b - U+01dbf - U+0200b - U+0200f - U+030fc - U+030fe - U+03260 - U+0327f - U+0fb46 - U+0fbb1 - U+10450 - U+1049d - -12. The -o option (show only the matching part of a line) for pcregrep was not - compatible with GNU grep in that, if there was more than one match in a - line, it showed only the first of them. It now behaves in the same way as - GNU grep. - -13. If the -o and -v options were combined for pcregrep, it printed a blank - line for every non-matching line. GNU grep prints nothing, and pcregrep now - does the same. The return code can be used to tell if there were any - non-matching lines. - -14. Added --file-offsets and --line-offsets to pcregrep. - -15. The pattern (?=something)(?R) was not being diagnosed as a potentially - infinitely looping recursion. The bug was that positive lookaheads were not - being skipped when checking for a possible empty match (negative lookaheads - and both kinds of lookbehind were skipped). - -16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the - inclusion of <windows.h> to before rather than after the definition of - INVALID_FILE_ATTRIBUTES (patch from David Byron). - -17. Specifying a possessive quantifier with a specific limit for a Unicode - character property caused pcre_compile() to compile bad code, which led at - runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this - are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that - caused the error; without that there was no problem. - -18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2. - -19. Added --enable-pcretest-libreadline. - -20. In pcrecpp.cc, the variable 'count' was incremented twice in - RE::GlobalReplace(). As a result, the number of replacements returned was - double what it should be. I removed one of the increments, but Craig sent a - later patch that removed the other one (the right fix) and added unit tests - that check the return values (which was not done before). - -21. Several CMake things: - - (1) Arranged that, when cmake is used on Unix, the libraries end up with - the names libpcre and libpcreposix, not just pcre and pcreposix. - - (2) The above change means that pcretest and pcregrep are now correctly - linked with the newly-built libraries, not previously installed ones. - - (3) Added PCRE_SUPPORT_LIBREADLINE, PCRE_SUPPORT_LIBZ, PCRE_SUPPORT_LIBBZ2. - -22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.* - crashed when matching a string such as a\x{2029}b (note that \x{2029} is a - UTF-8 newline character). The key issue is that the pattern starts .*; - this means that the match must be either at the beginning, or after a - newline. The bug was in the code for advancing after a failed match and - checking that the new position followed a newline. It was not taking - account of UTF-8 characters correctly. - -23. PCRE was behaving differently from Perl in the way it recognized POSIX - character classes. PCRE was not treating the sequence [:...:] as a - character class unless the ... were all letters. Perl, however, seems to - allow any characters between [: and :], though of course it rejects as - unknown any "names" that contain non-letters, because all the known class - names consist only of letters. Thus, Perl gives an error for [[:1234:]], - for example, whereas PCRE did not - it did not recognize a POSIX character - class. This seemed a bit dangerous, so the code has been changed to be - closer to Perl. The behaviour is not identical to Perl, because PCRE will - diagnose an unknown class for, for example, [[:l\ower:]] where Perl will - treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where - Perl does, and where it didn't before. - -24. Rewrite so as to remove the single use of %n from pcregrep because in some - Windows environments %n is disabled by default. - - -Version 7.4 21-Sep-07 ---------------------- - -1. Change 7.3/28 was implemented for classes by looking at the bitmap. This - means that a class such as [\s] counted as "explicit reference to CR or - LF". That isn't really right - the whole point of the change was to try to - help when there was an actual mention of one of the two characters. So now - the change happens only if \r or \n (or a literal CR or LF) character is - encountered. - -2. The 32-bit options word was also used for 6 internal flags, but the numbers - of both had grown to the point where there were only 3 bits left. - Fortunately, there was spare space in the data structure, and so I have - moved the internal flags into a new 16-bit field to free up more option - bits. - -3. The appearance of (?J) at the start of a pattern set the DUPNAMES option, - but did not set the internal JCHANGED flag - either of these is enough to - control the way the "get" function works - but the PCRE_INFO_JCHANGED - facility is supposed to tell if (?J) was ever used, so now (?J) at the - start sets both bits. - -4. Added options (at build time, compile time, exec time) to change \R from - matching any Unicode line ending sequence to just matching CR, LF, or CRLF. - -5. doc/pcresyntax.html was missing from the distribution. - -6. Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward - compatibility, even though it is no longer used. - -7. Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and - strtoull to pcrecpp.cc to select the available functions in WIN32 when the - windows.h file is present (where different names are used). [This was - reversed later after testing - see 16 below.] - -8. Changed all #include <config.h> to #include "config.h". There were also - some further <pcre.h> cases that I changed to "pcre.h". - -9. When pcregrep was used with the --colour option, it missed the line ending - sequence off the lines that it output. - -10. It was pointed out to me that arrays of string pointers cause lots of - relocations when a shared library is dynamically loaded. A technique of - using a single long string with a table of offsets can drastically reduce - these. I have refactored PCRE in four places to do this. The result is - dramatic: - - Originally: 290 - After changing UCP table: 187 - After changing error message table: 43 - After changing table of "verbs" 36 - After changing table of Posix names 22 - - Thanks to the folks working on Gregex for glib for this insight. - -11. --disable-stack-for-recursion caused compiling to fail unless -enable- - unicode-properties was also set. - -12. Updated the tests so that they work when \R is defaulted to ANYCRLF. - -13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously - checked only for CRLF. - -14. Added casts to pcretest.c to avoid compiler warnings. - -15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings. - -16. Added Craig's patch to remove the WINDOWS_H tests, that were not working, - and instead check for _strtoi64 explicitly, and avoid the use of snprintf() - entirely. This removes changes made in 7 above. - -17. The CMake files have been updated, and there is now more information about - building with CMake in the NON-UNIX-USE document. - - -Version 7.3 28-Aug-07 ---------------------- - - 1. In the rejigging of the build system that eventually resulted in 7.1, the - line "#include <pcre.h>" was included in pcre_internal.h. The use of angle - brackets there is not right, since it causes compilers to look for an - installed pcre.h, not the version that is in the source that is being - compiled (which of course may be different). I have changed it back to: - - #include "pcre.h" - - I have a vague recollection that the change was concerned with compiling in - different directories, but in the new build system, that is taken care of - by the VPATH setting the Makefile. - - 2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed - when the subject happened to end in the byte 0x85 (e.g. if the last - character was \x{1ec5}). *Character* 0x85 is one of the "any" newline - characters but of course it shouldn't be taken as a newline when it is part - of another character. The bug was that, for an unlimited repeat of . in - not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by - characters when looking for a newline. - - 3. A small performance improvement in the DOTALL UTF-8 mode .* case. - - 4. Debugging: adjusted the names of opcodes for different kinds of parentheses - in debug output. - - 5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for - long printing in the pcrecpp unittest when running under MinGW. - - 6. ESC_K was left out of the EBCDIC table. - - 7. Change 7.0/38 introduced a new limit on the number of nested non-capturing - parentheses; I made it 1000, which seemed large enough. Unfortunately, the - limit also applies to "virtual nesting" when a pattern is recursive, and in - this case 1000 isn't so big. I have been able to remove this limit at the - expense of backing off one optimization in certain circumstances. Normally, - when pcre_exec() would call its internal match() function recursively and - immediately return the result unconditionally, it uses a "tail recursion" - feature to save stack. However, when a subpattern that can match an empty - string has an unlimited repetition quantifier, it no longer makes this - optimization. That gives it a stack frame in which to save the data for - checking that an empty string has been matched. Previously this was taken - from the 1000-entry workspace that had been reserved. So now there is no - explicit limit, but more stack is used. - - 8. Applied Daniel's patches to solve problems with the import/export magic - syntax that is required for Windows, and which was going wrong for the - pcreposix and pcrecpp parts of the library. These were overlooked when this - problem was solved for the main library. - - 9. There were some crude static tests to avoid integer overflow when computing - the size of patterns that contain repeated groups with explicit upper - limits. As the maximum quantifier is 65535, the maximum group length was - set at 30,000 so that the product of these two numbers did not overflow a - 32-bit integer. However, it turns out that people want to use groups that - are longer than 30,000 bytes (though not repeat them that many times). - Change 7.0/17 (the refactoring of the way the pattern size is computed) has - made it possible to implement the integer overflow checks in a much more - dynamic way, which I have now done. The artificial limitation on group - length has been removed - we now have only the limit on the total length of - the compiled pattern, which depends on the LINK_SIZE setting. - -10. Fixed a bug in the documentation for get/copy named substring when - duplicate names are permitted. If none of the named substrings are set, the - functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an - empty string. - -11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E - instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error, - because the ] is interpreted as the first data character and the - terminating ] is not found. PCRE has been made compatible with Perl in this - regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could - cause memory overwriting. - -10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty - string has been matched (to stop an infinite loop). It was not recognizing - a conditional subpattern that could match an empty string if that - subpattern was within another subpattern. For example, it looped when - trying to match (((?(1)X|))*) but it was OK with ((?(1)X|)*) where the - condition was not nested. This bug has been fixed. - -12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack - past the start of the subject in the presence of bytes with the top bit - set, for example "\x8aBCD". - -13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE), - (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT). - -14. Optimized (?!) to (*FAIL). - -15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629. - This restricts code points to be within the range 0 to 0x10FFFF, excluding - the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the - full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still - does: it's just the validity check that is more restrictive. - -16. Inserted checks for integer overflows during escape sequence (backslash) - processing, and also fixed erroneous offset values for syntax errors during - backslash processing. - -17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above) - for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80". - -18. An unterminated class in a pattern like (?1)\c[ with a "forward reference" - caused an overrun. - -19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with - something other than just ASCII characters) inside a group that had an - unlimited repeat caused a loop at compile time (while checking to see - whether the group could match an empty string). - -20. Debugging a pattern containing \p or \P could cause a crash. For example, - [\P{Any}] did so. (Error in the code for printing property names.) - -21. An orphan \E inside a character class could cause a crash. - -22. A repeated capturing bracket such as (A)? could cause a wild memory - reference during compilation. - -23. There are several functions in pcre_compile() that scan along a compiled - expression for various reasons (e.g. to see if it's fixed length for look - behind). There were bugs in these functions when a repeated \p or \P was - present in the pattern. These operators have additional parameters compared - with \d, etc, and these were not being taken into account when moving along - the compiled data. Specifically: - - (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed - length. - - (b) An item such as \pL+ within a repeated group could cause crashes or - loops. - - (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect - "reference to non-existent subpattern" error. - - (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time. - -24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte - characters were involved (for example /\S{2}/8g with "A\x{a3}BC"). - -25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop. - -26. Patterns such as [\P{Yi}A] which include \p or \P and just one other - character were causing crashes (broken optimization). - -27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing - \p or \P) caused a compile-time loop. - -28. More problems have arisen in unanchored patterns when CRLF is a valid line - break. For example, the unstudied pattern [\r\n]A does not match the string - "\r\nA" because change 7.0/46 below moves the current point on by two - characters after failing to match at the start. However, the pattern \nA - *does* match, because it doesn't start till \n, and if [\r\n]A is studied, - the same is true. There doesn't seem any very clean way out of this, but - what I have chosen to do makes the common cases work: PCRE now takes note - of whether there can be an explicit match for \r or \n anywhere in the - pattern, and if so, 7.0/46 no longer applies. As part of this change, - there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled - pattern has explicit CR or LF references. - -29. Added (*CR) etc for changing newline setting at start of pattern. - - -Version 7.2 19-Jun-07 ---------------------- - - 1. If the fr_FR locale cannot be found for test 3, try the "french" locale, - which is apparently normally available under Windows. - - 2. Re-jig the pcregrep tests with different newline settings in an attempt - to make them independent of the local environment's newline setting. - - 3. Add code to configure.ac to remove -g from the CFLAGS default settings. - - 4. Some of the "internals" tests were previously cut out when the link size - was not 2, because the output contained actual offsets. The recent new - "Z" feature of pcretest means that these can be cut out, making the tests - usable with all link sizes. - - 5. Implemented Stan Switzer's goto replacement for longjmp() when not using - stack recursion. This gives a massive performance boost under BSD, but just - a small improvement under Linux. However, it saves one field in the frame - in all cases. - - 6. Added more features from the forthcoming Perl 5.10: - - (a) (?-n) (where n is a string of digits) is a relative subroutine or - recursion call. It refers to the nth most recently opened parentheses. - - (b) (?+n) is also a relative subroutine call; it refers to the nth next - to be opened parentheses. - - (c) Conditions that refer to capturing parentheses can be specified - relatively, for example, (?(-2)... or (?(+3)... - - (d) \K resets the start of the current match so that everything before - is not part of it. - - (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible). - - (f) \g{name} is another synonym - part of Perl 5.10's unification of - reference syntax. - - (g) (?| introduces a group in which the numbering of parentheses in each - alternative starts with the same number. - - (h) \h, \H, \v, and \V match horizontal and vertical whitespace. - - 7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and - PCRE_INFO_JCHANGED. - - 8. A pattern such as (.*(.)?)* caused pcre_exec() to fail by either not - terminating or by crashing. Diagnosed by Viktor Griph; it was in the code - for detecting groups that can match an empty string. - - 9. A pattern with a very large number of alternatives (more than several - hundred) was running out of internal workspace during the pre-compile - phase, where pcre_compile() figures out how much memory will be needed. A - bit of new cunning has reduced the workspace needed for groups with - alternatives. The 1000-alternative test pattern now uses 12 bytes of - workspace instead of running out of the 4096 that are available. - -10. Inserted some missing (unsigned int) casts to get rid of compiler warnings. - -11. Applied patch from Google to remove an optimization that didn't quite work. - The report of the bug said: - - pcrecpp::RE("a*").FullMatch("aaa") matches, while - pcrecpp::RE("a*?").FullMatch("aaa") does not, and - pcrecpp::RE("a*?\\z").FullMatch("aaa") does again. - -12. If \p or \P was used in non-UTF-8 mode on a character greater than 127 - it matched the wrong number of bytes. - - -Version 7.1 24-Apr-07 ---------------------- - - 1. Applied Bob Rossi and Daniel G's patches to convert the build system to one - that is more "standard", making use of automake and other Autotools. There - is some re-arrangement of the files and adjustment of comments consequent - on this. - - 2. Part of the patch fixed a problem with the pcregrep tests. The test of -r - for recursive directory scanning broke on some systems because the files - are not scanned in any specific order and on different systems the order - was different. A call to "sort" has been inserted into RunGrepTest for the - approprate test as a short-term fix. In the longer term there may be an - alternative. - - 3. I had an email from Eric Raymond about problems translating some of PCRE's - man pages to HTML (despite the fact that I distribute HTML pages, some - people do their own conversions for various reasons). The problems - concerned the use of low-level troff macros .br and .in. I have therefore - removed all such uses from the man pages (some were redundant, some could - be replaced by .nf/.fi pairs). The 132html script that I use to generate - HTML has been updated to handle .nf/.fi and to complain if it encounters - .br or .in. - - 4. Updated comments in configure.ac that get placed in config.h.in and also - arranged for config.h to be included in the distribution, with the name - config.h.generic, for the benefit of those who have to compile without - Autotools (compare pcre.h, which is now distributed as pcre.h.generic). - - 5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan - Weber: (1) pcre_internal.h was missing some function renames; (2) updated - makevp.bat for the current PCRE, using the additional files - makevp_c.txt, makevp_l.txt, and pcregexp.pas. - - 6. A Windows user reported a minor discrepancy with test 2, which turned out - to be caused by a trailing space on an input line that had got lost in his - copy. The trailing space was an accident, so I've just removed it. - - 7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told - that is needed. - - 8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c) - as "const" (a) because they are and (b) because it helps the PHP - maintainers who have recently made a script to detect big data structures - in the php code that should be moved to the .rodata section. I remembered - to update Builducptable as well, so it won't revert if ucptable.h is ever - re-created. - - 9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c, - pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in - order to be able to cut out the UTF-8 tables in the latter when UTF-8 - support is not required. This saves 1.5-2K of code, which is important in - some applications. - - Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c - so as not to refer to the tables, even though these functions will never be - called when UTF-8 support is disabled. Otherwise there are problems with a - shared library. - -10. Fixed two bugs in the emulated memmove() function in pcre_internal.h: - - (a) It was defining its arguments as char * instead of void *. - - (b) It was assuming that all moves were upwards in memory; this was true - a long time ago when I wrote it, but is no longer the case. - - The emulated memove() is provided for those environments that have neither - memmove() nor bcopy(). I didn't think anyone used it these days, but that - is clearly not the case, as these two bugs were recently reported. - -11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt, - and Detrail to create the HTML documentation, the .txt form of the man - pages, and it removes trailing spaces from listed files. It also creates - pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter - case, it wraps all the #defines with #ifndefs. This script should be run - before "make dist". - -12. Fixed two fairly obscure bugs concerned with quantified caseless matching - with Unicode property support. - - (a) For a maximizing quantifier, if the two different cases of the - character were of different lengths in their UTF-8 codings (there are - some cases like this - I found 11), and the matching function had to - back up over a mixture of the two cases, it incorrectly assumed they - were both the same length. - - (b) When PCRE was configured to use the heap rather than the stack for - recursion during matching, it was not correctly preserving the data for - the other case of a UTF-8 character when checking ahead for a match - while processing a minimizing repeat. If the check also involved - matching a wide character, but failed, corruption could cause an - erroneous result when trying to check for a repeat of the original - character. - -13. Some tidying changes to the testing mechanism: - - (a) The RunTest script now detects the internal link size and whether there - is UTF-8 and UCP support by running ./pcretest -C instead of relying on - values substituted by "configure". (The RunGrepTest script already did - this for UTF-8.) The configure.ac script no longer substitutes the - relevant variables. - - (b) The debugging options /B and /D in pcretest show the compiled bytecode - with length and offset values. This means that the output is different - for different internal link sizes. Test 2 is skipped for link sizes - other than 2 because of this, bypassing the problem. Unfortunately, - there was also a test in test 3 (the locale tests) that used /B and - failed for link sizes other than 2. Rather than cut the whole test out, - I have added a new /Z option to pcretest that replaces the length and - offset values with spaces. This is now used to make test 3 independent - of link size. (Test 2 will be tidied up later.) - -14. If erroroffset was passed as NULL to pcre_compile, it provoked a - segmentation fault instead of returning the appropriate error message. - -15. In multiline mode when the newline sequence was set to "any", the pattern - ^$ would give a match between the \r and \n of a subject such as "A\r\nB". - This doesn't seem right; it now treats the CRLF combination as the line - ending, and so does not match in that case. It's only a pattern such as ^$ - that would hit this one: something like ^ABC$ would have failed after \r - and then tried again after \r\n. - -16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub" - in an attempt to make files that differ only in their line terminators - compare equal. This works on Linux. - -17. Under certain error circumstances pcregrep might try to free random memory - as it exited. This is now fixed, thanks to valgrind. - -19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string - "abc\r\n\r\n", it found an unwanted second match after the second \r. This - was because its rules for how to advance for /g after matching an empty - string at the end of a line did not allow for this case. They now check for - it specially. - -20. pcretest is supposed to handle patterns and data of any length, by - extending its buffers when necessary. It was getting this wrong when the - buffer for a data line had to be extended. - -21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or - CRLF as a newline sequence. - -22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut - out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but - I have nevertheless tidied it up. - -23. Added some casts to kill warnings from HP-UX ia64 compiler. - -24. Added a man page for pcre-config. - - -Version 7.0 19-Dec-06 ---------------------- - - 1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by - moving to gcc 4.1.1. - - 2. The -S option for pcretest uses setrlimit(); I had omitted to #include - sys/time.h, which is documented as needed for this function. It doesn't - seem to matter on Linux, but it showed up on some releases of OS X. - - 3. It seems that there are systems where bytes whose values are greater than - 127 match isprint() in the "C" locale. The "C" locale should be the - default when a C program starts up. In most systems, only ASCII printing - characters match isprint(). This difference caused the output from pcretest - to vary, making some of the tests fail. I have changed pcretest so that: - - (a) When it is outputting text in the compiled version of a pattern, bytes - other than 32-126 are always shown as hex escapes. - - (b) When it is outputting text that is a matched part of a subject string, - it does the same, unless a different locale has been set for the match - (using the /L modifier). In this case, it uses isprint() to decide. - - 4. Fixed a major bug that caused incorrect computation of the amount of memory - required for a compiled pattern when options that changed within the - pattern affected the logic of the preliminary scan that determines the - length. The relevant options are -x, and -i in UTF-8 mode. The result was - that the computed length was too small. The symptoms of this bug were - either the PCRE error "internal error: code overflow" from pcre_compile(), - or a glibc crash with a message such as "pcretest: free(): invalid next - size (fast)". Examples of patterns that provoked this bug (shown in - pcretest format) are: - - /(?-x: )/x - /(?x)(?-x: \s*#\s*)/ - /((?i)[\x{c0}])/8 - /(?i:[\x{c0}])/8 - - HOWEVER: Change 17 below makes this fix obsolete as the memory computation - is now done differently. - - 5. Applied patches from Google to: (a) add a QuoteMeta function to the C++ - wrapper classes; (b) implement a new function in the C++ scanner that is - more efficient than the old way of doing things because it avoids levels of - recursion in the regex matching; (c) add a paragraph to the documentation - for the FullMatch() function. - - 6. The escape sequence \n was being treated as whatever was defined as - "newline". Not only was this contrary to the documentation, which states - that \n is character 10 (hex 0A), but it also went horribly wrong when - "newline" was defined as CRLF. This has been fixed. - - 7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c) - was being set to -1 for the "end of line" case (supposedly a value that no - character can have). Though this value is never used (the check for end of - line is "zero bytes in current character"), it caused compiler complaints. - I've changed it to 0xffffffff. - - 8. In pcre_version.c, the version string was being built by a sequence of - C macros that, in the event of PCRE_PRERELEASE being defined as an empty - string (as it is for production releases) called a macro with an empty - argument. The C standard says the result of this is undefined. The gcc - compiler treats it as an empty string (which was what was wanted) but it is - reported that Visual C gives an error. The source has been hacked around to - avoid this problem. - - 9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows - builds of pcretest, and changed the call to _setmode() to use _O_BINARY - instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all - of them did). - -10. Originally, pcretest opened its input and output without "b"; then I was - told that "b" was needed in some environments, so it was added for release - 5.0 to both the input and output. (It makes no difference on Unix-like - systems.) Later I was told that it is wrong for the input on Windows. I've - now abstracted the modes into two macros, to make it easier to fiddle with - them, and removed "b" from the input mode under Windows. - -11. Added pkgconfig support for the C++ wrapper library, libpcrecpp. - -12. Added -help and --help to pcretest as an official way of being reminded - of the options. - -13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in - and pcrecpp.cc because they annoy compilers at high warning levels. - -14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop. - -15. Fixed an occurrence of == in configure.ac that should have been = (shell - scripts are not C programs :-) and which was not noticed because it works - on Linux. - -16. pcretest is supposed to handle any length of pattern and data line (as one - line or as a continued sequence of lines) by extending its input buffer if - necessary. This feature was broken for very long pattern lines, leading to - a string of junk being passed to pcre_compile() if the pattern was longer - than about 50K. - -17. I have done a major re-factoring of the way pcre_compile() computes the - amount of memory needed for a compiled pattern. Previously, there was code - that made a preliminary scan of the pattern in order to do this. That was - OK when PCRE was new, but as the facilities have expanded, it has become - harder and harder to keep it in step with the real compile phase, and there - have been a number of bugs (see for example, 4 above). I have now found a - cunning way of running the real compile function in a "fake" mode that - enables it to compute how much memory it would need, while actually only - ever using a few hundred bytes of working memory and without too many - tests of the mode. This should make future maintenance and development - easier. A side effect of this work is that the limit of 200 on the nesting - depth of parentheses has been removed (though this was never a serious - limitation, I suspect). However, there is a downside: pcre_compile() now - runs more slowly than before (30% or more, depending on the pattern). I - hope this isn't a big issue. There is no effect on runtime performance. - -18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a - newline (only possible for the last line of a file) and it was a - pattern that set a locale (followed by /Lsomething), pcretest crashed. - -19. Added additional timing features to pcretest. (1) The -tm option now times - matching only, not compiling. (2) Both -t and -tm can be followed, as a - separate command line item, by a number that specifies the number of - repeats to use when timing. The default is 50000; this gives better - precision, but takes uncomfortably long for very large patterns. - -20. Extended pcre_study() to be more clever in cases where a branch of a - subpattern has no definite first character. For example, (a*|b*)[cd] would - previously give no result from pcre_study(). Now it recognizes that the - first character must be a, b, c, or d. - -21. There was an incorrect error "recursive call could loop indefinitely" if - a subpattern (or the entire pattern) that was being tested for matching an - empty string contained only one non-empty item after a nested subpattern. - For example, the pattern (?>\x{100}*)\d(?R) provoked this error - incorrectly, because the \d was being skipped in the check. - -22. The pcretest program now has a new pattern option /B and a command line - option -b, which is equivalent to adding /B to every pattern. This causes - it to show the compiled bytecode, without the additional information that - -d shows. The effect of -d is now the same as -b with -i (and similarly, /D - is the same as /B/I). - -23. A new optimization is now able automatically to treat some sequences such - as a*b as a*+b. More specifically, if something simple (such as a character - or a simple class like \d) has an unlimited quantifier, and is followed by - something that cannot possibly match the quantified thing, the quantifier - is automatically "possessified". - -24. A recursive reference to a subpattern whose number was greater than 39 - went wrong under certain circumstances in UTF-8 mode. This bug could also - have affected the operation of pcre_study(). - -25. Realized that a little bit of performance could be had by replacing - (c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters. - -26. Timing data from pcretest is now shown to 4 decimal places instead of 3. - -27. Possessive quantifiers such as a++ were previously implemented by turning - them into atomic groups such as ($>a+). Now they have their own opcodes, - which improves performance. This includes the automatically created ones - from 23 above. - -28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a - lookahead was broken if it was not anchored. PCRE was mistakenly expecting - the first matched character to be a colon. This applied both to named and - numbered groups. - -29. The ucpinternal.h header file was missing its idempotency #ifdef. - -30. I was sent a "project" file called libpcre.a.dev which I understand makes - building PCRE on Windows easier, so I have included it in the distribution. - -31. There is now a check in pcretest against a ridiculously large number being - returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G - loop, the loop is abandoned. - -32. Forward references to subpatterns in conditions such as (?(2)...) where - subpattern 2 is defined later cause pcre_compile() to search forwards in - the pattern for the relevant set of parentheses. This search went wrong - when there were unescaped parentheses in a character class, parentheses - escaped with \Q...\E, or parentheses in a #-comment in /x mode. - -33. "Subroutine" calls and backreferences were previously restricted to - referencing subpatterns earlier in the regex. This restriction has now - been removed. - -34. Added a number of extra features that are going to be in Perl 5.10. On the - whole, these are just syntactic alternatives for features that PCRE had - previously implemented using the Python syntax or my own invention. The - other formats are all retained for compatibility. - - (a) Named groups can now be defined as (?<name>...) or (?'name'...) as well - as (?P<name>...). The new forms, as well as being in Perl 5.10, are - also .NET compatible. - - (b) A recursion or subroutine call to a named group can now be defined as - (?&name) as well as (?P>name). - - (c) A backreference to a named group can now be defined as \k<name> or - \k'name' as well as (?P=name). The new forms, as well as being in Perl - 5.10, are also .NET compatible. - - (d) A conditional reference to a named group can now use the syntax - (?(<name>) or (?('name') as well as (?(name). - - (e) A "conditional group" of the form (?(DEFINE)...) can be used to define - groups (named and numbered) that are never evaluated inline, but can be - called as "subroutines" from elsewhere. In effect, the DEFINE condition - is always false. There may be only one alternative in such a group. - - (f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well - as the simple (?(R). The condition is true only if the most recent - recursion is that of the given number or name. It does not search out - through the entire recursion stack. - - (g) The escape \gN or \g{N} has been added, where N is a positive or - negative number, specifying an absolute or relative reference. - -35. Tidied to get rid of some further signed/unsigned compiler warnings and - some "unreachable code" warnings. - -36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other - things, this adds five new scripts. - -37. Perl ignores orphaned \E escapes completely. PCRE now does the same. - There were also incompatibilities regarding the handling of \Q..\E inside - character classes, for example with patterns like [\Qa\E-\Qz\E] where the - hyphen was adjacent to \Q or \E. I hope I've cleared all this up now. - -38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group - matches an empty string, and forcibly breaks the loop. There were bugs in - this code in non-simple cases. For a pattern such as ^(a()*)* matched - against aaaa the result was just "a" rather than "aaaa", for example. Two - separate and independent bugs (that affected different cases) have been - fixed. - -39. Refactored the code to abolish the use of different opcodes for small - capturing bracket numbers. This is a tidy that I avoided doing when I - removed the limit on the number of capturing brackets for 3.5 back in 2001. - The new approach is not only tidier, it makes it possible to reduce the - memory needed to fix the previous bug (38). - -40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline - sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when - processing dot, circumflex, or dollar metacharacters, or #-comments in /x - mode. - -41. Add \R to match any Unicode newline sequence, as suggested in the Unicode - report. - -42. Applied patch, originally from Ari Pollak, modified by Google, to allow - copy construction and assignment in the C++ wrapper. - -43. Updated pcregrep to support "--newline=any". In the process, I fixed a - couple of bugs that could have given wrong results in the "--newline=crlf" - case. - -44. Added a number of casts and did some reorganization of signed/unsigned int - variables following suggestions from Dair Grant. Also renamed the variable - "this" as "item" because it is a C++ keyword. - -45. Arranged for dftables to add - - #include "pcre_internal.h" - - to pcre_chartables.c because without it, gcc 4.x may remove the array - definition from the final binary if PCRE is built into a static library and - dead code stripping is activated. - -46. For an unanchored pattern, if a match attempt fails at the start of a - newline sequence, and the newline setting is CRLF or ANY, and the next two - characters are CRLF, advance by two characters instead of one. - - -Version 6.7 04-Jul-06 ---------------------- - - 1. In order to handle tests when input lines are enormously long, pcretest has - been re-factored so that it automatically extends its buffers when - necessary. The code is crude, but this _is_ just a test program. The - default size has been increased from 32K to 50K. - - 2. The code in pcre_study() was using the value of the re argument before - testing it for NULL. (Of course, in any sensible call of the function, it - won't be NULL.) - - 3. The memmove() emulation function in pcre_internal.h, which is used on - systems that lack both memmove() and bcopy() - that is, hardly ever - - was missing a "static" storage class specifier. - - 4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns - containing an extended class (one that cannot be represented by a bitmap - because it contains high-valued characters or Unicode property items, e.g. - [\pZ]). Almost always one would set UTF-8 mode when processing such a - pattern, but PCRE should not loop if you do not (it no longer does). - [Detail: two cases were found: (a) a repeated subpattern containing an - extended class; (b) a recursive reference to a subpattern that followed a - previous extended class. It wasn't skipping over the extended class - correctly when UTF-8 mode was not set.] - - 5. A negated single-character class was not being recognized as fixed-length - in lookbehind assertions such as (?<=[^f]), leading to an incorrect - compile error "lookbehind assertion is not fixed length". - - 6. The RunPerlTest auxiliary script was showing an unexpected difference - between PCRE and Perl for UTF-8 tests. It turns out that it is hard to - write a Perl script that can interpret lines of an input file either as - byte characters or as UTF-8, which is what "perltest" was being required to - do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you - can't do is switch easily at run time between having the "use utf8;" pragma - or not. In the end, I fudged it by using the RunPerlTest script to insert - "use utf8;" explicitly for the UTF-8 tests. - - 7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at - the end of the subject string, contrary to the documentation and to what - Perl does. This was true of both matching functions. Now it matches only at - the start of the subject and immediately after *internal* newlines. - - 8. A call of pcre_fullinfo() from pcretest to get the option bits was passing - a pointer to an int instead of a pointer to an unsigned long int. This - caused problems on 64-bit systems. - - 9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another - instance of the 'standard' template library not being so standard". - -10. There was no check on the number of named subpatterns nor the maximum - length of a subpattern name. The product of these values is used to compute - the size of the memory block for a compiled pattern. By supplying a very - long subpattern name and a large number of named subpatterns, the size - computation could be caused to overflow. This is now prevented by limiting - the length of names to 32 characters, and the number of named subpatterns - to 10,000. - -11. Subpatterns that are repeated with specific counts have to be replicated in - the compiled pattern. The size of memory for this was computed from the - length of the subpattern and the repeat count. The latter is limited to - 65535, but there was no limit on the former, meaning that integer overflow - could in principle occur. The compiled length of a repeated subpattern is - now limited to 30,000 bytes in order to prevent this. - -12. Added the optional facility to have named substrings with the same name. - -13. Added the ability to use a named substring as a condition, using the - Python syntax: (?(name)yes|no). This overloads (?(R)... and names that - are numbers (not recommended). Forward references are permitted. - -14. Added forward references in named backreferences (if you see what I mean). - -15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the - pattern could run off the end of the subject. For example, the pattern - "(?s)(.{1,5})"8 did this with the subject "ab". - -16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if - PCRE_CASELESS was set when matching characters that were quantified with ? - or *. - -17. A character class other than a single negated character that had a minimum - but no maximum quantifier - for example [ab]{6,} - was not handled - correctly by pce_dfa_exec(). It would match only one character. - -18. A valid (though odd) pattern that looked like a POSIX character - class but used an invalid character after [ (for example [[,abc,]]) caused - pcre_compile() to give the error "Failed: internal error: code overflow" or - in some cases to crash with a glibc free() error. This could even happen if - the pattern terminated after [[ but there just happened to be a sequence of - letters, a binary zero, and a closing ] in the memory that followed. - -19. Perl's treatment of octal escapes in the range \400 to \777 has changed - over the years. Originally (before any Unicode support), just the bottom 8 - bits were taken. Thus, for example, \500 really meant \100. Nowadays the - output from "man perlunicode" includes this: - - The regular expression compiler produces polymorphic opcodes. That - is, the pattern adapts to the data and automatically switches to - the Unicode character scheme when presented with Unicode data--or - instead uses a traditional byte scheme when presented with byte - data. - - Sadly, a wide octal escape does not cause a switch, and in a string with - no other multibyte characters, these octal escapes are treated as before. - Thus, in Perl, the pattern /\500/ actually matches \100 but the pattern - /\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a - Unicode string. - - I have not perpetrated such confusion in PCRE. Up till now, it took just - the bottom 8 bits, as in old Perl. I have now made octal escapes with - values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they - translate to the appropriate multibyte character. - -29. Applied some refactoring to reduce the number of warnings from Microsoft - and Borland compilers. This has included removing the fudge introduced - seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused - a warning about an unused variable. - -21. PCRE has not included VT (character 0x0b) in the set of whitespace - characters since release 4.0, because Perl (from release 5.004) does not. - [Or at least, is documented not to: some releases seem to be in conflict - with the documentation.] However, when a pattern was studied with - pcre_study() and all its branches started with \s, PCRE still included VT - as a possible starting character. Of course, this did no harm; it just - caused an unnecessary match attempt. - -22. Removed a now-redundant internal flag bit that recorded the fact that case - dependency changed within the pattern. This was once needed for "required - byte" processing, but is no longer used. This recovers a now-scarce options - bit. Also moved the least significant internal flag bit to the most- - significant bit of the word, which was not previously used (hangover from - the days when it was an int rather than a uint) to free up another bit for - the future. - -23. Added support for CRLF line endings as well as CR and LF. As well as the - default being selectable at build time, it can now be changed at runtime - via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to - specify that it is scanning data with non-default line endings. - -24. Changed the definition of CXXLINK to make it agree with the definition of - LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS. - -25. Applied Ian Taylor's patches to avoid using another stack frame for tail - recursions. This makes a big different to stack usage for some patterns. - -26. If a subpattern containing a named recursion or subroutine reference such - as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of - the space required for the compiled pattern went wrong and gave too small a - value. Depending on the environment, this could lead to "Failed: internal - error: code overflow at offset 49" or "glibc detected double free or - corruption" errors. - -27. Applied patches from Google (a) to support the new newline modes and (b) to - advance over multibyte UTF-8 characters in GlobalReplace. - -28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a - difference for some implementation of PCRE in some Windows version. - -29. Added some extra testing facilities to pcretest: - - \q<number> in a data line sets the "match limit" value - \Q<number> in a data line sets the "match recursion limt" value - -S <number> sets the stack size, where <number> is in megabytes - - The -S option isn't available for Windows. - - -Version 6.6 06-Feb-06 ---------------------- - - 1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined - in pcreposix.h. I have copied the definition from pcre.h. - - 2. Change 25 for 6.5 broke compilation in a build directory out-of-tree - because pcre.h is no longer a built file. - - 3. Added Jeff Friedl's additional debugging patches to pcregrep. These are - not normally included in the compiled code. - - -Version 6.5 01-Feb-06 ---------------------- - - 1. When using the partial match feature with pcre_dfa_exec(), it was not - anchoring the second and subsequent partial matches at the new starting - point. This could lead to incorrect results. For example, with the pattern - /1234/, partially matching against "123" and then "a4" gave a match. - - 2. Changes to pcregrep: - - (a) All non-match returns from pcre_exec() were being treated as failures - to match the line. Now, unless the error is PCRE_ERROR_NOMATCH, an - error message is output. Some extra information is given for the - PCRE_ERROR_MATCHLIMIT and PCRE_ERROR_RECURSIONLIMIT errors, which are - probably the only errors that are likely to be caused by users (by - specifying a regex that has nested indefinite repeats, for instance). - If there are more than 20 of these errors, pcregrep is abandoned. - - (b) A binary zero was treated as data while matching, but terminated the - output line if it was written out. This has been fixed: binary zeroes - are now no different to any other data bytes. - - (c) Whichever of the LC_ALL or LC_CTYPE environment variables is set is - used to set a locale for matching. The --locale=xxxx long option has - been added (no short equivalent) to specify a locale explicitly on the - pcregrep command, overriding the environment variables. - - (d) When -B was used with -n, some line numbers in the output were one less - than they should have been. - - (e) Added the -o (--only-matching) option. - - (f) If -A or -C was used with -c (count only), some lines of context were - accidentally printed for the final match. - - (g) Added the -H (--with-filename) option. - - (h) The combination of options -rh failed to suppress file names for files - that were found from directory arguments. - - (i) Added the -D (--devices) and -d (--directories) options. - - (j) Added the -F (--fixed-strings) option. - - (k) Allow "-" to be used as a file name for -f as well as for a data file. - - (l) Added the --colo(u)r option. - - (m) Added Jeffrey Friedl's -S testing option, but within #ifdefs so that it - is not present by default. - - 3. A nasty bug was discovered in the handling of recursive patterns, that is, - items such as (?R) or (?1), when the recursion could match a number of - alternatives. If it matched one of the alternatives, but subsequently, - outside the recursion, there was a failure, the code tried to back up into - the recursion. However, because of the way PCRE is implemented, this is not - possible, and the result was an incorrect result from the match. - - In order to prevent this happening, the specification of recursion has - been changed so that all such subpatterns are automatically treated as - atomic groups. Thus, for example, (?R) is treated as if it were (?>(?R)). - - 4. I had overlooked the fact that, in some locales, there are characters for - which isalpha() is true but neither isupper() nor islower() are true. In - the fr_FR locale, for instance, the \xAA and \xBA characters (ordmasculine - and ordfeminine) are like this. This affected the treatment of \w and \W - when they appeared in character classes, but not when they appeared outside - a character class. The bit map for "word" characters is now created - separately from the results of isalnum() instead of just taking it from the - upper, lower, and digit maps. (Plus the underscore character, of course.) - - 5. The above bug also affected the handling of POSIX character classes such as - [[:alpha:]] and [[:alnum:]]. These do not have their own bit maps in PCRE's - permanent tables. Instead, the bit maps for such a class were previously - created as the appropriate unions of the upper, lower, and digit bitmaps. - Now they are created by subtraction from the [[:word:]] class, which has - its own bitmap. - - 6. The [[:blank:]] character class matches horizontal, but not vertical space. - It is created by subtracting the vertical space characters (\x09, \x0a, - \x0b, \x0c) from the [[:space:]] bitmap. Previously, however, the - subtraction was done in the overall bitmap for a character class, meaning - that a class such as [\x0c[:blank:]] was incorrect because \x0c would not - be recognized. This bug has been fixed. - - 7. Patches from the folks at Google: - - (a) pcrecpp.cc: "to handle a corner case that may or may not happen in - real life, but is still worth protecting against". - - (b) pcrecpp.cc: "corrects a bug when negative radixes are used with - regular expressions". - - (c) pcre_scanner.cc: avoid use of std::count() because not all systems - have it. - - (d) Split off pcrecpparg.h from pcrecpp.h and had the former built by - "configure" and the latter not, in order to fix a problem somebody had - with compiling the Arg class on HP-UX. - - (e) Improve the error-handling of the C++ wrapper a little bit. - - (f) New tests for checking recursion limiting. - - 8. The pcre_memmove() function, which is used only if the environment does not - have a standard memmove() function (and is therefore rarely compiled), - contained two bugs: (a) use of int instead of size_t, and (b) it was not - returning a result (though PCRE never actually uses the result). - - 9. In the POSIX regexec() interface, if nmatch is specified as a ridiculously - large number - greater than INT_MAX/(3*sizeof(int)) - REG_ESPACE is - returned instead of calling malloc() with an overflowing number that would - most likely cause subsequent chaos. - -10. The debugging option of pcretest was not showing the NO_AUTO_CAPTURE flag. - -11. The POSIX flag REG_NOSUB is now supported. When a pattern that was compiled - with this option is matched, the nmatch and pmatch options of regexec() are - ignored. - -12. Added REG_UTF8 to the POSIX interface. This is not defined by POSIX, but is - provided in case anyone wants to the the POSIX interface with UTF-8 - strings. - -13. Added CXXLDFLAGS to the Makefile parameters to provide settings only on the - C++ linking (needed for some HP-UX environments). - -14. Avoid compiler warnings in get_ucpname() when compiled without UCP support - (unused parameter) and in the pcre_printint() function (omitted "default" - switch label when the default is to do nothing). - -15. Added some code to make it possible, when PCRE is compiled as a C++ - library, to replace subject pointers for pcre_exec() with a smart pointer - class, thus making it possible to process discontinuous strings. - -16. The two macros PCRE_EXPORT and PCRE_DATA_SCOPE are confusing, and perform - much the same function. They were added by different people who were trying - to make PCRE easy to compile on non-Unix systems. It has been suggested - that PCRE_EXPORT be abolished now that there is more automatic apparatus - for compiling on Windows systems. I have therefore replaced it with - PCRE_DATA_SCOPE. This is set automatically for Windows; if not set it - defaults to "extern" for C or "extern C" for C++, which works fine on - Unix-like systems. It is now possible to override the value of PCRE_DATA_ - SCOPE with something explicit in config.h. In addition: - - (a) pcreposix.h still had just "extern" instead of either of these macros; - I have replaced it with PCRE_DATA_SCOPE. - - (b) Functions such as _pcre_xclass(), which are internal to the library, - but external in the C sense, all had PCRE_EXPORT in their definitions. - This is apparently wrong for the Windows case, so I have removed it. - (It makes no difference on Unix-like systems.) - -17. Added a new limit, MATCH_LIMIT_RECURSION, which limits the depth of nesting - of recursive calls to match(). This is different to MATCH_LIMIT because - that limits the total number of calls to match(), not all of which increase - the depth of recursion. Limiting the recursion depth limits the amount of - stack (or heap if NO_RECURSE is set) that is used. The default can be set - when PCRE is compiled, and changed at run time. A patch from Google adds - this functionality to the C++ interface. - -18. Changes to the handling of Unicode character properties: - - (a) Updated the table to Unicode 4.1.0. - - (b) Recognize characters that are not in the table as "Cn" (undefined). - - (c) I revised the way the table is implemented to a much improved format - which includes recognition of ranges. It now supports the ranges that - are defined in UnicodeData.txt, and it also amalgamates other - characters into ranges. This has reduced the number of entries in the - table from around 16,000 to around 3,000, thus reducing its size - considerably. I realized I did not need to use a tree structure after - all - a binary chop search is just as efficient. Having reduced the - number of entries, I extended their size from 6 bytes to 8 bytes to - allow for more data. - - (d) Added support for Unicode script names via properties such as \p{Han}. - -19. In UTF-8 mode, a backslash followed by a non-Ascii character was not - matching that character. - -20. When matching a repeated Unicode property with a minimum greater than zero, - (for example \pL{2,}), PCRE could look past the end of the subject if it - reached it while seeking the minimum number of characters. This could - happen only if some of the characters were more than one byte long, because - there is a check for at least the minimum number of bytes. - -21. Refactored the implementation of \p and \P so as to be more general, to - allow for more different types of property in future. This has changed the - compiled form incompatibly. Anybody with saved compiled patterns that use - \p or \P will have to recompile them. - -22. Added "Any" and "L&" to the supported property types. - -23. Recognize \x{...} as a code point specifier, even when not in UTF-8 mode, - but give a compile time error if the value is greater than 0xff. - -24. The man pages for pcrepartial, pcreprecompile, and pcre_compile2 were - accidentally not being installed or uninstalled. - -25. The pcre.h file was built from pcre.h.in, but the only changes that were - made were to insert the current release number. This seemed silly, because - it made things harder for people building PCRE on systems that don't run - "configure". I have turned pcre.h into a distributed file, no longer built - by "configure", with the version identification directly included. There is - no longer a pcre.h.in file. - - However, this change necessitated a change to the pcre-config script as - well. It is built from pcre-config.in, and one of the substitutions was the - release number. I have updated configure.ac so that ./configure now finds - the release number by grepping pcre.h. - -26. Added the ability to run the tests under valgrind. - - -Version 6.4 05-Sep-05 ---------------------- - - 1. Change 6.0/10/(l) to pcregrep introduced a bug that caused separator lines - "--" to be printed when multiple files were scanned, even when none of the - -A, -B, or -C options were used. This is not compatible with Gnu grep, so I - consider it to be a bug, and have restored the previous behaviour. - - 2. A couple of code tidies to get rid of compiler warnings. - - 3. The pcretest program used to cheat by referring to symbols in the library - whose names begin with _pcre_. These are internal symbols that are not - really supposed to be visible externally, and in some environments it is - possible to suppress them. The cheating is now confined to including - certain files from the library's source, which is a bit cleaner. - - 4. Renamed pcre.in as pcre.h.in to go with pcrecpp.h.in; it also makes the - file's purpose clearer. - - 5. Reorganized pcre_ucp_findchar(). - - -Version 6.3 15-Aug-05 ---------------------- - - 1. The file libpcre.pc.in did not have general read permission in the tarball. - - 2. There were some problems when building without C++ support: - - (a) If C++ support was not built, "make install" and "make test" still - tried to test it. - - (b) There were problems when the value of CXX was explicitly set. Some - changes have been made to try to fix these, and ... - - (c) --disable-cpp can now be used to explicitly disable C++ support. - - (d) The use of @CPP_OBJ@ directly caused a blank line preceded by a - backslash in a target when C++ was disabled. This confuses some - versions of "make", apparently. Using an intermediate variable solves - this. (Same for CPP_LOBJ.) - - 3. $(LINK_FOR_BUILD) now includes $(CFLAGS_FOR_BUILD) and $(LINK) - (non-Windows) now includes $(CFLAGS) because these flags are sometimes - necessary on certain architectures. - - 4. Added a setting of -export-symbols-regex to the link command to remove - those symbols that are exported in the C sense, but actually are local - within the library, and not documented. Their names all begin with - "_pcre_". This is not a perfect job, because (a) we have to except some - symbols that pcretest ("illegally") uses, and (b) the facility isn't always - available (and never for static libraries). I have made a note to try to - find a way round (a) in the future. - - -Version 6.2 01-Aug-05 ---------------------- - - 1. There was no test for integer overflow of quantifier values. A construction - such as {1111111111111111} would give undefined results. What is worse, if - a minimum quantifier for a parenthesized subpattern overflowed and became - negative, the calculation of the memory size went wrong. This could have - led to memory overwriting. - - 2. Building PCRE using VPATH was broken. Hopefully it is now fixed. - - 3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like - operating environments where this matters. - - 4. Applied Giuseppe Maxia's patch to add additional features for controlling - PCRE options from within the C++ wrapper. - - 5. Named capturing subpatterns were not being correctly counted when a pattern - was compiled. This caused two problems: (a) If there were more than 100 - such subpatterns, the calculation of the memory needed for the whole - compiled pattern went wrong, leading to an overflow error. (b) Numerical - back references of the form \12, where the number was greater than 9, were - not recognized as back references, even though there were sufficient - previous subpatterns. - - 6. Two minor patches to pcrecpp.cc in order to allow it to compile on older - versions of gcc, e.g. 2.95.4. - - -Version 6.1 21-Jun-05 ---------------------- - - 1. There was one reference to the variable "posix" in pcretest.c that was not - surrounded by "#if !defined NOPOSIX". - - 2. Make it possible to compile pcretest without DFA support, UTF8 support, or - the cross-check on the old pcre_info() function, for the benefit of the - cut-down version of PCRE that is currently imported into Exim. - - 3. A (silly) pattern starting with (?i)(?-i) caused an internal space - allocation error. I've done the easy fix, which wastes 2 bytes for sensible - patterns that start (?i) but I don't think that matters. The use of (?i) is - just an example; this all applies to the other options as well. - - 4. Since libtool seems to echo the compile commands it is issuing, the output - from "make" can be reduced a bit by putting "@" in front of each libtool - compile command. - - 5. Patch from the folks at Google for configure.in to be a bit more thorough - in checking for a suitable C++ installation before trying to compile the - C++ stuff. This should fix a reported problem when a compiler was present, - but no suitable headers. - - 6. The man pages all had just "PCRE" as their title. I have changed them to - be the relevant file name. I have also arranged that these names are - retained in the file doc/pcre.txt, which is a concatenation in text format - of all the man pages except the little individual ones for each function. - - 7. The NON-UNIX-USE file had not been updated for the different set of source - files that come with release 6. I also added a few comments about the C++ - wrapper. - - -Version 6.0 07-Jun-05 ---------------------- - - 1. Some minor internal re-organization to help with my DFA experiments. - - 2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that - didn't matter for the library itself when fully configured, but did matter - when compiling without UCP support, or within Exim, where the ucp files are - not imported. - - 3. Refactoring of the library code to split up the various functions into - different source modules. The addition of the new DFA matching code (see - below) to a single monolithic source would have made it really too - unwieldy, quite apart from causing all the code to be include in a - statically linked application, when only some functions are used. This is - relevant even without the DFA addition now that patterns can be compiled in - one application and matched in another. - - The downside of splitting up is that there have to be some external - functions and data tables that are used internally in different modules of - the library but which are not part of the API. These have all had their - names changed to start with "_pcre_" so that they are unlikely to clash - with other external names. - - 4. Added an alternate matching function, pcre_dfa_exec(), which matches using - a different (DFA) algorithm. Although it is slower than the original - function, it does have some advantages for certain types of matching - problem. - - 5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(), - including restarting after a partial match. - - 6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not - defined when compiling for Windows was sent to me. I have put it into the - code, though I have no means of testing or verifying it. - - 7. Added the pcre_refcount() auxiliary function. - - 8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to - match before or at the first newline in the subject string. In pcretest, - the /f option on a pattern can be used to set this. - - 9. A repeated \w when used in UTF-8 mode with characters greater than 256 - would behave wrongly. This has been present in PCRE since release 4.0. - -10. A number of changes to the pcregrep command: - - (a) Refactored how -x works; insert ^(...)$ instead of setting - PCRE_ANCHORED and checking the length, in preparation for adding - something similar for -w. - - (b) Added the -w (match as a word) option. - - (c) Refactored the way lines are read and buffered so as to have more - than one at a time available. - - (d) Implemented a pcregrep test script. - - (e) Added the -M (multiline match) option. This allows patterns to match - over several lines of the subject. The buffering ensures that at least - 8K, or the rest of the document (whichever is the shorter) is available - for matching (and similarly the previous 8K for lookbehind assertions). - - (f) Changed the --help output so that it now says - - -w, --word-regex(p) - - instead of two lines, one with "regex" and the other with "regexp" - because that confused at least one person since the short forms are the - same. (This required a bit of code, as the output is generated - automatically from a table. It wasn't just a text change.) - - (g) -- can be used to terminate pcregrep options if the next thing isn't an - option but starts with a hyphen. Could be a pattern or a path name - starting with a hyphen, for instance. - - (h) "-" can be given as a file name to represent stdin. - - (i) When file names are being printed, "(standard input)" is used for - the standard input, for compatibility with GNU grep. Previously - "<stdin>" was used. - - (j) The option --label=xxx can be used to supply a name to be used for - stdin when file names are being printed. There is no short form. - - (k) Re-factored the options decoding logic because we are going to add - two more options that take data. Such options can now be given in four - different ways, e.g. "-fname", "-f name", "--file=name", "--file name". - - (l) Added the -A, -B, and -C options for requesting that lines of context - around matches be printed. - - (m) Added the -L option to print the names of files that do not contain - any matching lines, that is, the complement of -l. - - (n) The return code is 2 if any file cannot be opened, but pcregrep does - continue to scan other files. - - (o) The -s option was incorrectly implemented. For compatibility with other - greps, it now suppresses the error message for a non-existent or non- - accessible file (but not the return code). There is a new option called - -q that suppresses the output of matching lines, which was what -s was - previously doing. - - (p) Added --include and --exclude options to specify files for inclusion - and exclusion when recursing. - -11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly. - Hopefully, it now does. - -12. Missing cast in pcre_study(). - -13. Added an "uninstall" target to the makefile. - -14. Replaced "extern" in the function prototypes in Makefile.in with - "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix - world, but is set differently for Windows. - -15. Added a second compiling function called pcre_compile2(). The only - difference is that it has an extra argument, which is a pointer to an - integer error code. When there is a compile-time failure, this is set - non-zero, in addition to the error test pointer being set to point to an - error message. The new argument may be NULL if no error number is required - (but then you may as well call pcre_compile(), which is now just a - wrapper). This facility is provided because some applications need a - numeric error indication, but it has also enabled me to tidy up the way - compile-time errors are handled in the POSIX wrapper. - -16. Added VPATH=.libs to the makefile; this should help when building with one - prefix path and installing with another. (Or so I'm told by someone who - knows more about this stuff than I do.) - -17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This - passes PCRE_DOTALL to the pcre_compile() function, making the "." character - match everything, including newlines. This is not POSIX-compatible, but - somebody wanted the feature. From pcretest it can be activated by using - both the P and the s flags. - -18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one. - -19. libpcre.pc was being incorrectly installed as executable. - -20. A couple of places in pcretest check for end-of-line by looking for '\n'; - it now also looks for '\r' so that it will work unmodified on Windows. - -21. Added Google's contributed C++ wrapper to the distribution. - -22. Added some untidy missing memory free() calls in pcretest, to keep - Electric Fence happy when testing. - - - -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 3.1 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. - -**** |