ViewVC logotype

Diff of /code/trunk/ChangeLog

Parent Directory Parent Directory | Revision Log Revision Log | View Patch Patch

revision 73 by nigel, Sat Feb 24 21:40:30 2007 UTC revision 428 by ph10, Mon Aug 31 17:10:26 2009 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
4    Version 8.00 ??-???-??
5    ----------------------
7    1.  The table for translating pcre_compile() error codes into POSIX error codes
8        was out-of-date, and there was no check on the pcre_compile() error code
9        being within the table. This could lead to an OK return being given in
10        error.
12    2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
13        "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
14        in a Windows environment.
16    3.  The pcregrep --count option prints the count for each file even when it is
17        zero, as does GNU grep. However, pcregrep was also printing all files when
18        --files-with-matches was added. Now, when both options are given, it prints
19        counts only for those files that have at least one match. (GNU grep just
20        prints the file name in this circumstance, but including the count seems
21        more useful - otherwise, why use --count?) Also ensured that the
22        combination -clh just lists non-zero counts, with no names.
24    4.  The long form of the pcregrep -F option was incorrectly implemented as
25        --fixed_strings instead of --fixed-strings. This is an incompatible change,
26        but it seems right to fix it, and I didn't think it was worth preserving
27        the old behaviour.
29    5.  The command line items --regex=pattern and --regexp=pattern were not
30        recognized by pcregrep, which required --regex pattern or --regexp pattern
31        (with a space rather than an '='). The man page documented the '=' forms,
32        which are compatible with GNU grep; these now work.
34    6.  No libpcreposix.pc file was created for pkg-config; there was just
35        libpcre.pc and libpcrecpp.pc. The omission has been rectified.
37    7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
38        when UCP support is not needed, by modifying the Python script that
39        generates it from Unicode data files. This should not matter if the module
40        is correctly used as a library, but I received one complaint about 50K of
41        unwanted data. My guess is that the person linked everything into his
42        program rather than using a library. Anyway, it does no harm.
44    8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
45        was a minimum greater than 1 for a wide character in a possessive
46        repetition. Chaos could result.
48    9.  The restrictions on what a pattern can contain when partial matching is
49        requested for pcre_exec() have been removed. All patterns can now be
50        partially matched by this function. In addition, if there are at least two
51        slots in the offset vector, the offsets of the first-encountered partial
52        match are set in them when PCRE_ERROR_PARTIAL is returned.
54    10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
55        synonymous with PCRE_PARTIAL, for backwards compatibility, and
56        PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
57        and may be more useful for multi-segment matching, especially with
58        pcre_exec().
60    11. Partial matching with pcre_exec() is now more intuitive. A partial match
61        used to be given if ever the end of the subject was reached; now it is
62        given only if matching could not proceed because another character was
63        needed. This makes a difference in some odd cases such as Z(*FAIL) with the
64        string "Z", which now yields "no match" instead of "partial match". In the
65        case of pcre_dfa_exec(), "no match" is given if every matching path for the
66        final character ended with (*FAIL).
68    12. Restarting a match using pcre_dfa_exec() after a partial match did not work
69        if the pattern had a "must contain" character that was already found in the
70        earlier partial match, unless partial matching was again requested. For
71        example, with the pattern /dog.(body)?/, the "must contain" character is
72        "g". If the first part-match was for the string "dog", restarting with
73        "sbody" failed.
76    Version 7.9 11-Apr-09
77    ---------------------
79    1.  When building with support for bzlib/zlib (pcregrep) and/or readline
80        (pcretest), all targets were linked against these libraries. This included
81        libpcre, libpcreposix, and libpcrecpp, even though they do not use these
82        libraries. This caused unwanted dependencies to be created. This problem
83        has been fixed, and now only pcregrep is linked with bzlib/zlib and only
84        pcretest is linked with readline.
86    2.  The "typedef int BOOL" in pcre_internal.h that was included inside the
87        "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
88        moved outside it again, because FALSE and TRUE are already defined in AIX,
89        but BOOL is not.
91    3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
92        PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
94    4.  The pcregrep documentation said spaces were inserted as well as colons (or
95        hyphens) following file names and line numbers when outputting matching
96        lines. This is not true; no spaces are inserted. I have also clarified the
97        wording for the --colour (or --color) option.
99    5.  In pcregrep, when --colour was used with -o, the list of matching strings
100        was not coloured; this is different to GNU grep, so I have changed it to be
101        the same.
103    6.  When --colo(u)r was used in pcregrep, only the first matching substring in
104        each matching line was coloured. Now it goes on to look for further matches
105        of any of the test patterns, which is the same behaviour as GNU grep.
107    7.  A pattern that could match an empty string could cause pcregrep to loop; it
108        doesn't make sense to accept an empty string match in pcregrep, so I have
109        locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
110        seems to be how GNU grep behaves.
112    8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
113        start or after a newline", because the conditional assertion was not being
114        correctly handled. The rule now is that both the assertion and what follows
115        in the first alternative must satisfy the test.
117    9.  If auto-callout was enabled in a pattern with a conditional group whose
118        condition was an assertion, PCRE could crash during matching, both with
119        pcre_exec() and pcre_dfa_exec().
121    10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
122        used for matching.
124    11. Unicode property support in character classes was not working for
125        characters (bytes) greater than 127 when not in UTF-8 mode.
127    12. Added the -M command line option to pcretest.
129    14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
131    15. Added the PCRE_NO_START_OPTIMIZE match-time option.
133    16. Added comments and documentation about mis-use of no_arg in the C++
134        wrapper.
136    17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
137        from Martin Jerabek that uses macro names for all relevant character and
138        string constants.
140    18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
141        SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
142        SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
143        these, but not everybody uses configure.
145    19. A conditional group that had only one branch was not being correctly
146        recognized as an item that could match an empty string. This meant that an
147        enclosing group might also not be so recognized, causing infinite looping
148        (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
149        with the subject "ab", where knowledge that the repeated group can match
150        nothing is needed in order to break the loop.
152    20. If a pattern that was compiled with callouts was matched using pcre_dfa_
153        exec(), but without supplying a callout function, matching went wrong.
155    21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
156        leak if the size of the offset vector was greater than 30. When the vector
157        is smaller, the saved offsets during recursion go onto a local stack
158        vector, but for larger vectors malloc() is used. It was failing to free
159        when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
160        error, in fact).
162    22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
163        heapframe that is used only when UTF-8 support is enabled. This caused no
164        problem, but was untidy.
166    23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
167        CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
168        included within another project.
170    24. Steven Van Ingelgem's patches to add more options to the CMake support,
171        slightly modified by me:
173          (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
174              not building pcregrep.
176          (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
177              if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
179    25. Forward references, both numeric and by name, in patterns that made use of
180        duplicate group numbers, could behave incorrectly or give incorrect errors,
181        because when scanning forward to find the reference group, PCRE was not
182        taking into account the duplicate group numbers. A pattern such as
183        ^X(?3)(a)(?|(b)|(q))(Y) is an example.
185    26. Changed a few more instances of "const unsigned char *" to USPTR, making
186        the feature of a custom pointer more persuasive (as requested by a user).
188    27. Wrapped the definitions of fileno and isatty for Windows, which appear in
189        pcretest.c, inside #ifndefs, because it seems they are sometimes already
190        pre-defined.
192    28. Added support for (*UTF8) at the start of a pattern.
194    29. Arrange for flags added by the "release type" setting in CMake to be shown
195        in the configuration summary.
198    Version 7.8 05-Sep-08
199    ---------------------
201    1.  Replaced UCP searching code with optimized version as implemented for Ad
202        Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
203        stage table and inline lookup instead of a function, giving speed ups of 2
204        to 5 times on some simple patterns that I tested. Permission was given to
205        distribute the MultiStage2.py script that generates the tables (it's not in
206        the tarball, but is in the Subversion repository).
208    2.  Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
209        scripts.
211    3.  Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
212        a group with a zero qualifier. The result of the study could be incorrect,
213        or the function might crash, depending on the pattern.
215    4.  Caseless matching was not working for non-ASCII characters in back
216        references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
217        It now works when Unicode Property Support is available.
219    5.  In pcretest, an escape such as \x{de} in the data was always generating
220        a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
221        non-UTF-8 mode. If the value is greater than 255, it gives a warning about
222        truncation.
224    6.  Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
226    7.  Added two (int) casts to pcregrep when printing the difference of two
227        pointers, in case they are 64-bit values.
229    8.  Added comments about Mac OS X stack usage to the pcrestack man page and to
230        test 2 if it fails.
232    9.  Added PCRE_CALL_CONVENTION just before the names of all exported functions,
233        and a #define of that name to empty if it is not externally set. This is to
234        allow users of MSVC to set it if necessary.
236    10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
237        the convenience functions in the pcre_get.c source file.
239    11. An option change at the start of a pattern that had top-level alternatives
240        could cause overwriting and/or a crash. This command provoked a crash in
241        some environments:
243          printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
245        This potential security problem was recorded as CVE-2008-2371.
247    12. For a pattern where the match had to start at the beginning or immediately
248        after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
249        pcre_dfa_exec() could read past the end of the passed subject if there was
250        no match. To help with detecting such bugs (e.g. with valgrind), I modified
251        pcretest so that it places the subject at the end of its malloc-ed buffer.
253    13. The change to pcretest in 12 above threw up a couple more cases when pcre_
254        exec() might read past the end of the data buffer in UTF-8 mode.
256    14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
257        the data contained the byte 0x85 as part of a UTF-8 character within its
258        first line. This applied both to normal and DFA matching.
260    15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
261        /^[^d]*?$/8 failed to match "abc".
263    16. Added a missing copyright notice to pcrecpp_internal.h.
265    17. Make it more clear in the documentation that values returned from
266        pcre_exec() in ovector are byte offsets, not character counts.
268    18. Tidied a few places to stop certain compilers from issuing warnings.
270    19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
271        supplied by Stefan Weber. I made a further small update for 7.8 because
272        there is a change of source arrangements: the pcre_searchfuncs.c module is
273        replaced by pcre_ucd.c.
276    Version 7.7 07-May-08
277    ---------------------
279    1.  Applied Craig's patch to sort out a long long problem: "If we can't convert
280        a string to a long long, pretend we don't even have a long long." This is
281        done by checking for the strtoq, strtoll, and _strtoi64 functions.
283    2.  Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
284        pre-7.6 versions, which defined a global no_arg variable instead of putting
285        it in the RE class. (See also #8 below.)
287    3.  Remove a line of dead code, identified by coverity and reported by Nuno
288        Lopes.
290    4.  Fixed two related pcregrep bugs involving -r with --include or --exclude:
292        (1) The include/exclude patterns were being applied to the whole pathnames
293            of files, instead of just to the final components.
295        (2) If there was more than one level of directory, the subdirectories were
296            skipped unless they satisfied the include/exclude conditions. This is
297            inconsistent with GNU grep (and could even be seen as contrary to the
298            pcregrep specification - which I improved to make it absolutely clear).
299            The action now is always to scan all levels of directory, and just
300            apply the include/exclude patterns to regular files.
302    5.  Added the --include_dir and --exclude_dir patterns to pcregrep, and used
303        --exclude_dir in the tests to avoid scanning .svn directories.
305    6.  Applied Craig's patch to the QuoteMeta function so that it escapes the
306        NUL character as backslash + 0 rather than backslash + NUL, because PCRE
307        doesn't support NULs in patterns.
309    7.  Added some missing "const"s to declarations of static tables in
310        pcre_compile.c and pcre_dfa_exec.c.
312    8.  Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
313        caused by fix #2  above. (Subsequently also a second patch to fix the
314        first patch. And a third patch - this was a messy problem.)
316    9.  Applied Craig's patch to remove the use of push_back().
318    10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
319        matching function regexec().
321    11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
322        which, however, unlike Perl's \g{...}, are subroutine calls, not back
323        references. PCRE supports relative numbers with this syntax (I don't think
324        Oniguruma does).
326    12. Previously, a group with a zero repeat such as (...){0} was completely
327        omitted from the compiled regex. However, this means that if the group
328        was called as a subroutine from elsewhere in the pattern, things went wrong
329        (an internal error was given). Such groups are now left in the compiled
330        pattern, with a new opcode that causes them to be skipped at execution
331        time.
333    13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
334        to the way PCRE behaves:
336        (a) A lone ] character is dis-allowed (Perl treats it as data).
338        (b) A back reference to an unmatched subpattern matches an empty string
339            (Perl fails the current match path).
341        (c) A data ] in a character class must be notated as \] because if the
342            first data character in a class is ], it defines an empty class. (In
343            Perl it is not possible to have an empty class.) The empty class []
344            never matches; it forces failure and is equivalent to (*FAIL) or (?!).
345            The negative empty class [^] matches any one character, independently
346            of the DOTALL setting.
348    14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
349        non-existent subpattern following a character class starting with ']' and
350        containing () gave an internal compiling error instead of "reference to
351        non-existent subpattern". Fortunately, when the pattern did exist, the
352        compiled code was correct. (When scanning forwards to check for the
353        existencd of the subpattern, it was treating the data ']' as terminating
354        the class, so got the count wrong. When actually compiling, the reference
355        was subsequently set up correctly.)
357    15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
358        it was being rejected as not supported by pcre_dfa_exec(), even though
359        other assertions are supported. I have made pcre_dfa_exec() support
360        (*FAIL).
362    16. The implementation of 13c above involved the invention of a new opcode,
363        OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
364        cannot be changed at match time, I realized I could make a small
365        improvement to matching performance by compiling OP_ALLANY instead of
366        OP_ANY for "." when DOTALL was set, and then removing the runtime tests
367        on the OP_ANY path.
369    17. Compiling pcretest on Windows with readline support failed without the
370        following two fixes: (1) Make the unistd.h include conditional on
371        HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
373    18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
374        ncurses library to be included for pcretest when ReadLine support is
375        requested, but also to allow for it to be overridden. This patch came from
376        Daniel Bergström.
378    19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
379        as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
380        any errors with the current Unicode tables. Thanks to Peter Kankowski for
381        spotting this.
384    Version 7.6 28-Jan-08
385    ---------------------
387    1.  A character class containing a very large number of characters with
388        codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
389        overflow.
391    2.  Patch to cut out the "long long" test in pcrecpp_unittest when
392        HAVE_LONG_LONG is not defined.
394    3.  Applied Christian Ehrlicher's patch to update the CMake build files to
395        bring them up to date and include new features. This patch includes:
397        - Fixed PH's badly added libz and libbz2 support.
398        - Fixed a problem with static linking.
399        - Added pcredemo. [But later removed - see 7 below.]
400        - Fixed dftables problem and added an option.
401        - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
402            HAVE_LONG_LONG.
403        - Added readline support for pcretest.
404        - Added an listing of the option settings after cmake has run.
406    4.  A user submitted a patch to Makefile that makes it easy to create
407        "pcre.dll" under mingw when using Configure/Make. I added stuff to
408        Makefile.am that cause it to include this special target, without
409        affecting anything else. Note that the same mingw target plus all
410        the other distribution libraries and programs are now supported
411        when configuring with CMake (see 6 below) instead of with
412        Configure/Make.
414    5.  Applied Craig's patch that moves no_arg into the RE class in the C++ code.
415        This is an attempt to solve the reported problem "pcrecpp::no_arg is not
416        exported in the Windows port". It has not yet been confirmed that the patch
417        solves the problem, but it does no harm.
419    6.  Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
420        NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
421        with CMake, and also correct the comment about stack recursion.
423    7.  Remove the automatic building of pcredemo from the ./configure system and
424        from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
425        of a program that users should build themselves after PCRE is installed, so
426        building it automatically is not really right. What is more, it gave
427        trouble in some build environments.
429    8.  Further tidies to CMakeLists.txt from Sheri and Christian.
432    Version 7.5 10-Jan-08
433    ---------------------
435    1.  Applied a patch from Craig: "This patch makes it possible to 'ignore'
436        values in parens when parsing an RE using the C++ wrapper."
438    2.  Negative specials like \S did not work in character classes in UTF-8 mode.
439        Characters greater than 255 were excluded from the class instead of being
440        included.
442    3.  The same bug as (2) above applied to negated POSIX classes such as
443        [:^space:].
445    4.  PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
446        defined or documented. It seems to have been a typo for PCRE_STATIC, so
447        I have changed it.
449    5.  The construct (?&) was not diagnosed as a syntax error (it referenced the
450        first named subpattern) and a construct such as (?&a) would reference the
451        first named subpattern whose name started with "a" (in other words, the
452        length check was missing). Both these problems are fixed. "Subpattern name
453        expected" is now given for (?&) (a zero-length name), and this patch also
454        makes it give the same error for \k'' (previously it complained that that
455        was a reference to a non-existent subpattern).
457    6.  The erroneous patterns (?+-a) and (?-+a) give different error messages;
458        this is right because (?- can be followed by option settings as well as by
459        digits. I have, however, made the messages clearer.
461    7.  Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
462        than the number used in the conditional) now cause a compile-time error.
463        This is actually not compatible with Perl, which accepts such patterns, but
464        treats the conditional as always being FALSE (as PCRE used to), but it
465        seems to me that giving a diagnostic is better.
467    8.  Change "alphameric" to the more common word "alphanumeric" in comments
468        and messages.
470    9.  Fix two occurrences of "backslash" in comments that should have been
471        "backspace".
473    10. Remove two redundant lines of code that can never be obeyed (their function
474        was moved elsewhere).
476    11. The program that makes PCRE's Unicode character property table had a bug
477        which caused it to generate incorrect table entries for sequences of
478        characters that have the same character type, but are in different scripts.
479        It amalgamated them into a single range, with the script of the first of
480        them. In other words, some characters were in the wrong script. There were
481        thirteen such cases, affecting characters in the following ranges:
483          U+002b0 - U+002c1
484          U+0060c - U+0060d
485          U+0061e - U+00612
486          U+0064b - U+0065e
487          U+0074d - U+0076d
488          U+01800 - U+01805
489          U+01d00 - U+01d77
490          U+01d9b - U+01dbf
491          U+0200b - U+0200f
492          U+030fc - U+030fe
493          U+03260 - U+0327f
494          U+0fb46 - U+0fbb1
495          U+10450 - U+1049d
497    12. The -o option (show only the matching part of a line) for pcregrep was not
498        compatible with GNU grep in that, if there was more than one match in a
499        line, it showed only the first of them. It now behaves in the same way as
500        GNU grep.
502    13. If the -o and -v options were combined for pcregrep, it printed a blank
503        line for every non-matching line. GNU grep prints nothing, and pcregrep now
504        does the same. The return code can be used to tell if there were any
505        non-matching lines.
507    14. Added --file-offsets and --line-offsets to pcregrep.
509    15. The pattern (?=something)(?R) was not being diagnosed as a potentially
510        infinitely looping recursion. The bug was that positive lookaheads were not
511        being skipped when checking for a possible empty match (negative lookaheads
512        and both kinds of lookbehind were skipped).
514    16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
515        inclusion of <windows.h> to before rather than after the definition of
516        INVALID_FILE_ATTRIBUTES (patch from David Byron).
518    17. Specifying a possessive quantifier with a specific limit for a Unicode
519        character property caused pcre_compile() to compile bad code, which led at
520        runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
521        are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
522        caused the error; without that there was no problem.
524    18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
526    19. Added --enable-pcretest-libreadline.
528    20. In pcrecpp.cc, the variable 'count' was incremented twice in
529        RE::GlobalReplace(). As a result, the number of replacements returned was
530        double what it should be. I removed one of the increments, but Craig sent a
531        later patch that removed the other one (the right fix) and added unit tests
532        that check the return values (which was not done before).
534    21. Several CMake things:
536        (1) Arranged that, when cmake is used on Unix, the libraries end up with
537            the names libpcre and libpcreposix, not just pcre and pcreposix.
539        (2) The above change means that pcretest and pcregrep are now correctly
540            linked with the newly-built libraries, not previously installed ones.
544    22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
545        crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
546        UTF-8 newline character). The key issue is that the pattern starts .*;
547        this means that the match must be either at the beginning, or after a
548        newline. The bug was in the code for advancing after a failed match and
549        checking that the new position followed a newline. It was not taking
550        account of UTF-8 characters correctly.
552    23. PCRE was behaving differently from Perl in the way it recognized POSIX
553        character classes. PCRE was not treating the sequence [:...:] as a
554        character class unless the ... were all letters. Perl, however, seems to
555        allow any characters between [: and :], though of course it rejects as
556        unknown any "names" that contain non-letters, because all the known class
557        names consist only of letters. Thus, Perl gives an error for [[:1234:]],
558        for example, whereas PCRE did not - it did not recognize a POSIX character
559        class. This seemed a bit dangerous, so the code has been changed to be
560        closer to Perl. The behaviour is not identical to Perl, because PCRE will
561        diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
562        treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
563        Perl does, and where it didn't before.
565    24. Rewrite so as to remove the single use of %n from pcregrep because in some
566        Windows environments %n is disabled by default.
569    Version 7.4 21-Sep-07
570    ---------------------
572    1.  Change 7.3/28 was implemented for classes by looking at the bitmap. This
573        means that a class such as [\s] counted as "explicit reference to CR or
574        LF". That isn't really right - the whole point of the change was to try to
575        help when there was an actual mention of one of the two characters. So now
576        the change happens only if \r or \n (or a literal CR or LF) character is
577        encountered.
579    2.  The 32-bit options word was also used for 6 internal flags, but the numbers
580        of both had grown to the point where there were only 3 bits left.
581        Fortunately, there was spare space in the data structure, and so I have
582        moved the internal flags into a new 16-bit field to free up more option
583        bits.
585    3.  The appearance of (?J) at the start of a pattern set the DUPNAMES option,
586        but did not set the internal JCHANGED flag - either of these is enough to
587        control the way the "get" function works - but the PCRE_INFO_JCHANGED
588        facility is supposed to tell if (?J) was ever used, so now (?J) at the
589        start sets both bits.
591    4.  Added options (at build time, compile time, exec time) to change \R from
592        matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
594    5.  doc/pcresyntax.html was missing from the distribution.
596    6.  Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
597        compatibility, even though it is no longer used.
599    7.  Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
600        strtoull to pcrecpp.cc to select the available functions in WIN32 when the
601        windows.h file is present (where different names are used). [This was
602        reversed later after testing - see 16 below.]
604    8.  Changed all #include <config.h> to #include "config.h". There were also
605        some further <pcre.h> cases that I changed to "pcre.h".
607    9.  When pcregrep was used with the --colour option, it missed the line ending
608        sequence off the lines that it output.
610    10. It was pointed out to me that arrays of string pointers cause lots of
611        relocations when a shared library is dynamically loaded. A technique of
612        using a single long string with a table of offsets can drastically reduce
613        these. I have refactored PCRE in four places to do this. The result is
614        dramatic:
616          Originally:                          290
617          After changing UCP table:            187
618          After changing error message table:   43
619          After changing table of "verbs"       36
620          After changing table of Posix names   22
622        Thanks to the folks working on Gregex for glib for this insight.
624    11. --disable-stack-for-recursion caused compiling to fail unless -enable-
625        unicode-properties was also set.
627    12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
629    13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
630        checked only for CRLF.
632    14. Added casts to pcretest.c to avoid compiler warnings.
634    15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
636    16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
637        and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
638        entirely. This removes changes made in 7 above.
640    17. The CMake files have been updated, and there is now more information about
641        building with CMake in the NON-UNIX-USE document.
644    Version 7.3 28-Aug-07
645    ---------------------
647     1. In the rejigging of the build system that eventually resulted in 7.1, the
648        line "#include <pcre.h>" was included in pcre_internal.h. The use of angle
649        brackets there is not right, since it causes compilers to look for an
650        installed pcre.h, not the version that is in the source that is being
651        compiled (which of course may be different). I have changed it back to:
653          #include "pcre.h"
655        I have a vague recollection that the change was concerned with compiling in
656        different directories, but in the new build system, that is taken care of
657        by the VPATH setting the Makefile.
659     2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
660        when the subject happened to end in the byte 0x85 (e.g. if the last
661        character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
662        characters but of course it shouldn't be taken as a newline when it is part
663        of another character. The bug was that, for an unlimited repeat of . in
664        not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
665        characters when looking for a newline.
667     3. A small performance improvement in the DOTALL UTF-8 mode .* case.
669     4. Debugging: adjusted the names of opcodes for different kinds of parentheses
670        in debug output.
672     5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
673        long printing in the pcrecpp unittest when running under MinGW.
675     6. ESC_K was left out of the EBCDIC table.
677     7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
678        parentheses; I made it 1000, which seemed large enough. Unfortunately, the
679        limit also applies to "virtual nesting" when a pattern is recursive, and in
680        this case 1000 isn't so big. I have been able to remove this limit at the
681        expense of backing off one optimization in certain circumstances. Normally,
682        when pcre_exec() would call its internal match() function recursively and
683        immediately return the result unconditionally, it uses a "tail recursion"
684        feature to save stack. However, when a subpattern that can match an empty
685        string has an unlimited repetition quantifier, it no longer makes this
686        optimization. That gives it a stack frame in which to save the data for
687        checking that an empty string has been matched. Previously this was taken
688        from the 1000-entry workspace that had been reserved. So now there is no
689        explicit limit, but more stack is used.
691     8. Applied Daniel's patches to solve problems with the import/export magic
692        syntax that is required for Windows, and which was going wrong for the
693        pcreposix and pcrecpp parts of the library. These were overlooked when this
694        problem was solved for the main library.
696     9. There were some crude static tests to avoid integer overflow when computing
697        the size of patterns that contain repeated groups with explicit upper
698        limits. As the maximum quantifier is 65535, the maximum group length was
699        set at 30,000 so that the product of these two numbers did not overflow a
700        32-bit integer. However, it turns out that people want to use groups that
701        are longer than 30,000 bytes (though not repeat them that many times).
702        Change 7.0/17 (the refactoring of the way the pattern size is computed) has
703        made it possible to implement the integer overflow checks in a much more
704        dynamic way, which I have now done. The artificial limitation on group
705        length has been removed - we now have only the limit on the total length of
706        the compiled pattern, which depends on the LINK_SIZE setting.
708    10. Fixed a bug in the documentation for get/copy named substring when
709        duplicate names are permitted. If none of the named substrings are set, the
710        functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
711        empty string.
713    11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E
714        instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error,
715        because the ] is interpreted as the first data character and the
716        terminating ] is not found. PCRE has been made compatible with Perl in this
717        regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could
718        cause memory overwriting.
720    10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty
721        string has been matched (to stop an infinite loop). It was not recognizing
722        a conditional subpattern that could match an empty string if that
723        subpattern was within another subpattern. For example, it looped when
724        trying to match  (((?(1)X|))*)  but it was OK with  ((?(1)X|)*)  where the
725        condition was not nested. This bug has been fixed.
727    12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
728        past the start of the subject in the presence of bytes with the top bit
729        set, for example "\x8aBCD".
731    13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
732        (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
734    14. Optimized (?!) to (*FAIL).
736    15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
737        This restricts code points to be within the range 0 to 0x10FFFF, excluding
738        the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
739        full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
740        does: it's just the validity check that is more restrictive.
742    16. Inserted checks for integer overflows during escape sequence (backslash)
743        processing, and also fixed erroneous offset values for syntax errors during
744        backslash processing.
746    17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
747        for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
749    18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
750        caused an overrun.
752    19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
753        something other than just ASCII characters) inside a group that had an
754        unlimited repeat caused a loop at compile time (while checking to see
755        whether the group could match an empty string).
757    20. Debugging a pattern containing \p or \P could cause a crash. For example,
758        [\P{Any}] did so. (Error in the code for printing property names.)
760    21. An orphan \E inside a character class could cause a crash.
762    22. A repeated capturing bracket such as (A)? could cause a wild memory
763        reference during compilation.
765    23. There are several functions in pcre_compile() that scan along a compiled
766        expression for various reasons (e.g. to see if it's fixed length for look
767        behind). There were bugs in these functions when a repeated \p or \P was
768        present in the pattern. These operators have additional parameters compared
769        with \d, etc, and these were not being taken into account when moving along
770        the compiled data. Specifically:
772        (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
773            length.
775        (b) An item such as \pL+ within a repeated group could cause crashes or
776            loops.
778        (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
779            "reference to non-existent subpattern" error.
781        (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
783    24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
784        characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
786    25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
788    26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
789        character were causing crashes (broken optimization).
791    27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
792        \p or \P) caused a compile-time loop.
794    28. More problems have arisen in unanchored patterns when CRLF is a valid line
795        break. For example, the unstudied pattern [\r\n]A does not match the string
796        "\r\nA" because change 7.0/46 below moves the current point on by two
797        characters after failing to match at the start. However, the pattern \nA
798        *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
799        the same is true. There doesn't seem any very clean way out of this, but
800        what I have chosen to do makes the common cases work: PCRE now takes note
801        of whether there can be an explicit match for \r or \n anywhere in the
802        pattern, and if so, 7.0/46 no longer applies. As part of this change,
803        there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
804        pattern has explicit CR or LF references.
806    29. Added (*CR) etc for changing newline setting at start of pattern.
809    Version 7.2 19-Jun-07
810    ---------------------
812     1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
813        which is apparently normally available under Windows.
815     2. Re-jig the pcregrep tests with different newline settings in an attempt
816        to make them independent of the local environment's newline setting.
818     3. Add code to configure.ac to remove -g from the CFLAGS default settings.
820     4. Some of the "internals" tests were previously cut out when the link size
821        was not 2, because the output contained actual offsets. The recent new
822        "Z" feature of pcretest means that these can be cut out, making the tests
823        usable with all link sizes.
825     5. Implemented Stan Switzer's goto replacement for longjmp() when not using
826        stack recursion. This gives a massive performance boost under BSD, but just
827        a small improvement under Linux. However, it saves one field in the frame
828        in all cases.
830     6. Added more features from the forthcoming Perl 5.10:
832        (a) (?-n) (where n is a string of digits) is a relative subroutine or
833            recursion call. It refers to the nth most recently opened parentheses.
835        (b) (?+n) is also a relative subroutine call; it refers to the nth next
836            to be opened parentheses.
838        (c) Conditions that refer to capturing parentheses can be specified
839            relatively, for example, (?(-2)... or (?(+3)...
841        (d) \K resets the start of the current match so that everything before
842            is not part of it.
844        (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible).
846        (f) \g{name} is another synonym - part of Perl 5.10's unification of
847            reference syntax.
849        (g) (?| introduces a group in which the numbering of parentheses in each
850            alternative starts with the same number.
852        (h) \h, \H, \v, and \V match horizontal and vertical whitespace.
854     7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and
857     8. A pattern such as  (.*(.)?)*  caused pcre_exec() to fail by either not
858        terminating or by crashing. Diagnosed by Viktor Griph; it was in the code
859        for detecting groups that can match an empty string.
861     9. A pattern with a very large number of alternatives (more than several
862        hundred) was running out of internal workspace during the pre-compile
863        phase, where pcre_compile() figures out how much memory will be needed. A
864        bit of new cunning has reduced the workspace needed for groups with
865        alternatives. The 1000-alternative test pattern now uses 12 bytes of
866        workspace instead of running out of the 4096 that are available.
868    10. Inserted some missing (unsigned int) casts to get rid of compiler warnings.
870    11. Applied patch from Google to remove an optimization that didn't quite work.
871        The report of the bug said:
873          pcrecpp::RE("a*").FullMatch("aaa") matches, while
874          pcrecpp::RE("a*?").FullMatch("aaa") does not, and
875          pcrecpp::RE("a*?\\z").FullMatch("aaa") does again.
877    12. If \p or \P was used in non-UTF-8 mode on a character greater than 127
878        it matched the wrong number of bytes.
881    Version 7.1 24-Apr-07
882    ---------------------
884     1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
885        that is more "standard", making use of automake and other Autotools. There
886        is some re-arrangement of the files and adjustment of comments consequent
887        on this.
889     2. Part of the patch fixed a problem with the pcregrep tests. The test of -r
890        for recursive directory scanning broke on some systems because the files
891        are not scanned in any specific order and on different systems the order
892        was different. A call to "sort" has been inserted into RunGrepTest for the
893        approprate test as a short-term fix. In the longer term there may be an
894        alternative.
896     3. I had an email from Eric Raymond about problems translating some of PCRE's
897        man pages to HTML (despite the fact that I distribute HTML pages, some
898        people do their own conversions for various reasons). The problems
899        concerned the use of low-level troff macros .br and .in. I have therefore
900        removed all such uses from the man pages (some were redundant, some could
901        be replaced by .nf/.fi pairs). The 132html script that I use to generate
902        HTML has been updated to handle .nf/.fi and to complain if it encounters
903        .br or .in.
905     4. Updated comments in configure.ac that get placed in config.h.in and also
906        arranged for config.h to be included in the distribution, with the name
907        config.h.generic, for the benefit of those who have to compile without
908        Autotools (compare pcre.h, which is now distributed as pcre.h.generic).
910     5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
911        Weber: (1) pcre_internal.h was missing some function renames; (2) updated
912        makevp.bat for the current PCRE, using the additional files
913        makevp_c.txt, makevp_l.txt, and pcregexp.pas.
915     6. A Windows user reported a minor discrepancy with test 2, which turned out
916        to be caused by a trailing space on an input line that had got lost in his
917        copy. The trailing space was an accident, so I've just removed it.
919     7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told
920        that is needed.
922     8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c)
923        as "const" (a) because they are and (b) because it helps the PHP
924        maintainers who have recently made a script to detect big data structures
925        in the php code that should be moved to the .rodata section. I remembered
926        to update Builducptable as well, so it won't revert if ucptable.h is ever
927        re-created.
929     9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c,
930        pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in
931        order to be able to cut out the UTF-8 tables in the latter when UTF-8
932        support is not required. This saves 1.5-2K of code, which is important in
933        some applications.
935        Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c
936        so as not to refer to the tables, even though these functions will never be
937        called when UTF-8 support is disabled. Otherwise there are problems with a
938        shared library.
940    10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:
942        (a) It was defining its arguments as char * instead of void *.
944        (b) It was assuming that all moves were upwards in memory; this was true
945            a long time ago when I wrote it, but is no longer the case.
947        The emulated memove() is provided for those environments that have neither
948        memmove() nor bcopy(). I didn't think anyone used it these days, but that
949        is clearly not the case, as these two bugs were recently reported.
951    11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,
952        and Detrail to create the HTML documentation, the .txt form of the man
953        pages, and it removes trailing spaces from listed files. It also creates
954        pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter
955        case, it wraps all the #defines with #ifndefs. This script should be run
956        before "make dist".
958    12. Fixed two fairly obscure bugs concerned with quantified caseless matching
959        with Unicode property support.
961        (a) For a maximizing quantifier, if the two different cases of the
962            character were of different lengths in their UTF-8 codings (there are
963            some cases like this - I found 11), and the matching function had to
964            back up over a mixture of the two cases, it incorrectly assumed they
965            were both the same length.
967        (b) When PCRE was configured to use the heap rather than the stack for
968            recursion during matching, it was not correctly preserving the data for
969            the other case of a UTF-8 character when checking ahead for a match
970            while processing a minimizing repeat. If the check also involved
971            matching a wide character, but failed, corruption could cause an
972            erroneous result when trying to check for a repeat of the original
973            character.
975    13. Some tidying changes to the testing mechanism:
977        (a) The RunTest script now detects the internal link size and whether there
978            is UTF-8 and UCP support by running ./pcretest -C instead of relying on
979            values substituted by "configure". (The RunGrepTest script already did
980            this for UTF-8.) The configure.ac script no longer substitutes the
981            relevant variables.
983        (b) The debugging options /B and /D in pcretest show the compiled bytecode
984            with length and offset values. This means that the output is different
985            for different internal link sizes. Test 2 is skipped for link sizes
986            other than 2 because of this, bypassing the problem. Unfortunately,
987            there was also a test in test 3 (the locale tests) that used /B and
988            failed for link sizes other than 2. Rather than cut the whole test out,
989            I have added a new /Z option to pcretest that replaces the length and
990            offset values with spaces. This is now used to make test 3 independent
991            of link size. (Test 2 will be tidied up later.)
993    14. If erroroffset was passed as NULL to pcre_compile, it provoked a
994        segmentation fault instead of returning the appropriate error message.
996    15. In multiline mode when the newline sequence was set to "any", the pattern
997        ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
998        This doesn't seem right; it now treats the CRLF combination as the line
999        ending, and so does not match in that case. It's only a pattern such as ^$
1000        that would hit this one: something like ^ABC$ would have failed after \r
1001        and then tried again after \r\n.
1003    16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
1004        in an attempt to make files that differ only in their line terminators
1005        compare equal. This works on Linux.
1007    17. Under certain error circumstances pcregrep might try to free random memory
1008        as it exited. This is now fixed, thanks to valgrind.
1010    19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
1011        "abc\r\n\r\n", it found an unwanted second match after the second \r. This
1012        was because its rules for how to advance for /g after matching an empty
1013        string at the end of a line did not allow for this case. They now check for
1014        it specially.
1016    20. pcretest is supposed to handle patterns and data of any length, by
1017        extending its buffers when necessary. It was getting this wrong when the
1018        buffer for a data line had to be extended.
1020    21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
1021        CRLF as a newline sequence.
1023    22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
1024        out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
1025        I have nevertheless tidied it up.
1027    23. Added some casts to kill warnings from HP-UX ia64 compiler.
1029    24. Added a man page for pcre-config.
1032    Version 7.0 19-Dec-06
1033    ---------------------
1035     1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by
1036        moving to gcc 4.1.1.
1038     2. The -S option for pcretest uses setrlimit(); I had omitted to #include
1039        sys/time.h, which is documented as needed for this function. It doesn't
1040        seem to matter on Linux, but it showed up on some releases of OS X.
1042     3. It seems that there are systems where bytes whose values are greater than
1043        127 match isprint() in the "C" locale. The "C" locale should be the
1044        default when a C program starts up. In most systems, only ASCII printing
1045        characters match isprint(). This difference caused the output from pcretest
1046        to vary, making some of the tests fail. I have changed pcretest so that:
1048        (a) When it is outputting text in the compiled version of a pattern, bytes
1049            other than 32-126 are always shown as hex escapes.
1051        (b) When it is outputting text that is a matched part of a subject string,
1052            it does the same, unless a different locale has been set for the match
1053            (using the /L modifier). In this case, it uses isprint() to decide.
1055     4. Fixed a major bug that caused incorrect computation of the amount of memory
1056        required for a compiled pattern when options that changed within the
1057        pattern affected the logic of the preliminary scan that determines the
1058        length. The relevant options are -x, and -i in UTF-8 mode. The result was
1059        that the computed length was too small. The symptoms of this bug were
1060        either the PCRE error "internal error: code overflow" from pcre_compile(),
1061        or a glibc crash with a message such as "pcretest: free(): invalid next
1062        size (fast)". Examples of patterns that provoked this bug (shown in
1063        pcretest format) are:
1065          /(?-x: )/x
1066          /(?x)(?-x: \s*#\s*)/
1067          /((?i)[\x{c0}])/8
1068          /(?i:[\x{c0}])/8
1070        HOWEVER: Change 17 below makes this fix obsolete as the memory computation
1071        is now done differently.
1073     5. Applied patches from Google to: (a) add a QuoteMeta function to the C++
1074        wrapper classes; (b) implement a new function in the C++ scanner that is
1075        more efficient than the old way of doing things because it avoids levels of
1076        recursion in the regex matching; (c) add a paragraph to the documentation
1077        for the FullMatch() function.
1079     6. The escape sequence \n was being treated as whatever was defined as
1080        "newline". Not only was this contrary to the documentation, which states
1081        that \n is character 10 (hex 0A), but it also went horribly wrong when
1082        "newline" was defined as CRLF. This has been fixed.
1084     7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c)
1085        was being set to -1 for the "end of line" case (supposedly a value that no
1086        character can have). Though this value is never used (the check for end of
1087        line is "zero bytes in current character"), it caused compiler complaints.
1088        I've changed it to 0xffffffff.
1090     8. In pcre_version.c, the version string was being built by a sequence of
1091        C macros that, in the event of PCRE_PRERELEASE being defined as an empty
1092        string (as it is for production releases) called a macro with an empty
1093        argument. The C standard says the result of this is undefined. The gcc
1094        compiler treats it as an empty string (which was what was wanted) but it is
1095        reported that Visual C gives an error. The source has been hacked around to
1096        avoid this problem.
1098     9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows
1099        builds of pcretest, and changed the call to _setmode() to use _O_BINARY
1100        instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all
1101        of them did).
1103    10. Originally, pcretest opened its input and output without "b"; then I was
1104        told that "b" was needed in some environments, so it was added for release
1105        5.0 to both the input and output. (It makes no difference on Unix-like
1106        systems.) Later I was told that it is wrong for the input on Windows. I've
1107        now abstracted the modes into two macros, to make it easier to fiddle with
1108        them, and removed "b" from the input mode under Windows.
1110    11. Added pkgconfig support for the C++ wrapper library, libpcrecpp.
1112    12. Added -help and --help to pcretest as an official way of being reminded
1113        of the options.
1115    13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in
1116        and pcrecpp.cc because they annoy compilers at high warning levels.
1118    14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop.
1120    15. Fixed an occurrence of == in configure.ac that should have been = (shell
1121        scripts are not C programs :-) and which was not noticed because it works
1122        on Linux.
1124    16. pcretest is supposed to handle any length of pattern and data line (as one
1125        line or as a continued sequence of lines) by extending its input buffer if
1126        necessary. This feature was broken for very long pattern lines, leading to
1127        a string of junk being passed to pcre_compile() if the pattern was longer
1128        than about 50K.
1130    17. I have done a major re-factoring of the way pcre_compile() computes the
1131        amount of memory needed for a compiled pattern. Previously, there was code
1132        that made a preliminary scan of the pattern in order to do this. That was
1133        OK when PCRE was new, but as the facilities have expanded, it has become
1134        harder and harder to keep it in step with the real compile phase, and there
1135        have been a number of bugs (see for example, 4 above). I have now found a
1136        cunning way of running the real compile function in a "fake" mode that
1137        enables it to compute how much memory it would need, while actually only
1138        ever using a few hundred bytes of working memory and without too many
1139        tests of the mode. This should make future maintenance and development
1140        easier. A side effect of this work is that the limit of 200 on the nesting
1141        depth of parentheses has been removed (though this was never a serious
1142        limitation, I suspect). However, there is a downside: pcre_compile() now
1143        runs more slowly than before (30% or more, depending on the pattern). I
1144        hope this isn't a big issue. There is no effect on runtime performance.
1146    18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a
1147        newline (only possible for the last line of a file) and it was a
1148        pattern that set a locale (followed by /Lsomething), pcretest crashed.
1150    19. Added additional timing features to pcretest. (1) The -tm option now times
1151        matching only, not compiling. (2) Both -t and -tm can be followed, as a
1152        separate command line item, by a number that specifies the number of
1153        repeats to use when timing. The default is 50000; this gives better
1154        precision, but takes uncomfortably long for very large patterns.
1156    20. Extended pcre_study() to be more clever in cases where a branch of a
1157        subpattern has no definite first character. For example, (a*|b*)[cd] would
1158        previously give no result from pcre_study(). Now it recognizes that the
1159        first character must be a, b, c, or d.
1161    21. There was an incorrect error "recursive call could loop indefinitely" if
1162        a subpattern (or the entire pattern) that was being tested for matching an
1163        empty string contained only one non-empty item after a nested subpattern.
1164        For example, the pattern (?>\x{100}*)\d(?R) provoked this error
1165        incorrectly, because the \d was being skipped in the check.
1167    22. The pcretest program now has a new pattern option /B and a command line
1168        option -b, which is equivalent to adding /B to every pattern. This causes
1169        it to show the compiled bytecode, without the additional information that
1170        -d shows. The effect of -d is now the same as -b with -i (and similarly, /D
1171        is the same as /B/I).
1173    23. A new optimization is now able automatically to treat some sequences such
1174        as a*b as a*+b. More specifically, if something simple (such as a character
1175        or a simple class like \d) has an unlimited quantifier, and is followed by
1176        something that cannot possibly match the quantified thing, the quantifier
1177        is automatically "possessified".
1179    24. A recursive reference to a subpattern whose number was greater than 39
1180        went wrong under certain circumstances in UTF-8 mode. This bug could also
1181        have affected the operation of pcre_study().
1183    25. Realized that a little bit of performance could be had by replacing
1184        (c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters.
1186    26. Timing data from pcretest is now shown to 4 decimal places instead of 3.
1188    27. Possessive quantifiers such as a++ were previously implemented by turning
1189        them into atomic groups such as ($>a+). Now they have their own opcodes,
1190        which improves performance. This includes the automatically created ones
1191        from 23 above.
1193    28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a
1194        lookahead was broken if it was not anchored. PCRE was mistakenly expecting
1195        the first matched character to be a colon. This applied both to named and
1196        numbered groups.
1198    29. The ucpinternal.h header file was missing its idempotency #ifdef.
1200    30. I was sent a "project" file called libpcre.a.dev which I understand makes
1201        building PCRE on Windows easier, so I have included it in the distribution.
1203    31. There is now a check in pcretest against a ridiculously large number being
1204        returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G
1205        loop, the loop is abandoned.
1207    32. Forward references to subpatterns in conditions such as (?(2)...) where
1208        subpattern 2 is defined later cause pcre_compile() to search forwards in
1209        the pattern for the relevant set of parentheses. This search went wrong
1210        when there were unescaped parentheses in a character class, parentheses
1211        escaped with \Q...\E, or parentheses in a #-comment in /x mode.
1213    33. "Subroutine" calls and backreferences were previously restricted to
1214        referencing subpatterns earlier in the regex. This restriction has now
1215        been removed.
1217    34. Added a number of extra features that are going to be in Perl 5.10. On the
1218        whole, these are just syntactic alternatives for features that PCRE had
1219        previously implemented using the Python syntax or my own invention. The
1220        other formats are all retained for compatibility.
1222        (a) Named groups can now be defined as (?<name>...) or (?'name'...) as well
1223            as (?P<name>...). The new forms, as well as being in Perl 5.10, are
1224            also .NET compatible.
1226        (b) A recursion or subroutine call to a named group can now be defined as
1227            (?&name) as well as (?P>name).
1229        (c) A backreference to a named group can now be defined as \k<name> or
1230            \k'name' as well as (?P=name). The new forms, as well as being in Perl
1231            5.10, are also .NET compatible.
1233        (d) A conditional reference to a named group can now use the syntax
1234            (?(<name>) or (?('name') as well as (?(name).
1236        (e) A "conditional group" of the form (?(DEFINE)...) can be used to define
1237            groups (named and numbered) that are never evaluated inline, but can be
1238            called as "subroutines" from elsewhere. In effect, the DEFINE condition
1239            is always false. There may be only one alternative in such a group.
1241        (f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well
1242            as the simple (?(R). The condition is true only if the most recent
1243            recursion is that of the given number or name. It does not search out
1244            through the entire recursion stack.
1246        (g) The escape \gN or \g{N} has been added, where N is a positive or
1247            negative number, specifying an absolute or relative reference.
1249    35. Tidied to get rid of some further signed/unsigned compiler warnings and
1250        some "unreachable code" warnings.
1252    36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other
1253        things, this adds five new scripts.
1255    37. Perl ignores orphaned \E escapes completely. PCRE now does the same.
1256        There were also incompatibilities regarding the handling of \Q..\E inside
1257        character classes, for example with patterns like [\Qa\E-\Qz\E] where the
1258        hyphen was adjacent to \Q or \E. I hope I've cleared all this up now.
1260    38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group
1261        matches an empty string, and forcibly breaks the loop. There were bugs in
1262        this code in non-simple cases. For a pattern such as  ^(a()*)*  matched
1263        against  aaaa  the result was just "a" rather than "aaaa", for example. Two
1264        separate and independent bugs (that affected different cases) have been
1265        fixed.
1267    39. Refactored the code to abolish the use of different opcodes for small
1268        capturing bracket numbers. This is a tidy that I avoided doing when I
1269        removed the limit on the number of capturing brackets for 3.5 back in 2001.
1270        The new approach is not only tidier, it makes it possible to reduce the
1271        memory needed to fix the previous bug (38).
1273    40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline
1274        sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when
1275        processing dot, circumflex, or dollar metacharacters, or #-comments in /x
1276        mode.
1278    41. Add \R to match any Unicode newline sequence, as suggested in the Unicode
1279        report.
1281    42. Applied patch, originally from Ari Pollak, modified by Google, to allow
1282        copy construction and assignment in the C++ wrapper.
1284    43. Updated pcregrep to support "--newline=any". In the process, I fixed a
1285        couple of bugs that could have given wrong results in the "--newline=crlf"
1286        case.
1288    44. Added a number of casts and did some reorganization of signed/unsigned int
1289        variables following suggestions from Dair Grant. Also renamed the variable
1290        "this" as "item" because it is a C++ keyword.
1292    45. Arranged for dftables to add
1294          #include "pcre_internal.h"
1296        to pcre_chartables.c because without it, gcc 4.x may remove the array
1297        definition from the final binary if PCRE is built into a static library and
1298        dead code stripping is activated.
1300    46. For an unanchored pattern, if a match attempt fails at the start of a
1301        newline sequence, and the newline setting is CRLF or ANY, and the next two
1302        characters are CRLF, advance by two characters instead of one.
1305    Version 6.7 04-Jul-06
1306    ---------------------
1308     1. In order to handle tests when input lines are enormously long, pcretest has
1309        been re-factored so that it automatically extends its buffers when
1310        necessary. The code is crude, but this _is_ just a test program. The
1311        default size has been increased from 32K to 50K.
1313     2. The code in pcre_study() was using the value of the re argument before
1314        testing it for NULL. (Of course, in any sensible call of the function, it
1315        won't be NULL.)
1317     3. The memmove() emulation function in pcre_internal.h, which is used on
1318        systems that lack both memmove() and bcopy() - that is, hardly ever -
1319        was missing a "static" storage class specifier.
1321     4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns
1322        containing an extended class (one that cannot be represented by a bitmap
1323        because it contains high-valued characters or Unicode property items, e.g.
1324        [\pZ]). Almost always one would set UTF-8 mode when processing such a
1325        pattern, but PCRE should not loop if you do not (it no longer does).
1326        [Detail: two cases were found: (a) a repeated subpattern containing an
1327        extended class; (b) a recursive reference to a subpattern that followed a
1328        previous extended class. It wasn't skipping over the extended class
1329        correctly when UTF-8 mode was not set.]
1331     5. A negated single-character class was not being recognized as fixed-length
1332        in lookbehind assertions such as (?<=[^f]), leading to an incorrect
1333        compile error "lookbehind assertion is not fixed length".
1335     6. The RunPerlTest auxiliary script was showing an unexpected difference
1336        between PCRE and Perl for UTF-8 tests. It turns out that it is hard to
1337        write a Perl script that can interpret lines of an input file either as
1338        byte characters or as UTF-8, which is what "perltest" was being required to
1339        do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you
1340        can't do is switch easily at run time between having the "use utf8;" pragma
1341        or not. In the end, I fudged it by using the RunPerlTest script to insert
1342        "use utf8;" explicitly for the UTF-8 tests.
1344     7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at
1345        the end of the subject string, contrary to the documentation and to what
1346        Perl does. This was true of both matching functions. Now it matches only at
1347        the start of the subject and immediately after *internal* newlines.
1349     8. A call of pcre_fullinfo() from pcretest to get the option bits was passing
1350        a pointer to an int instead of a pointer to an unsigned long int. This
1351        caused problems on 64-bit systems.
1353     9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another
1354        instance of the 'standard' template library not being so standard".
1356    10. There was no check on the number of named subpatterns nor the maximum
1357        length of a subpattern name. The product of these values is used to compute
1358        the size of the memory block for a compiled pattern. By supplying a very
1359        long subpattern name and a large number of named subpatterns, the size
1360        computation could be caused to overflow. This is now prevented by limiting
1361        the length of names to 32 characters, and the number of named subpatterns
1362        to 10,000.
1364    11. Subpatterns that are repeated with specific counts have to be replicated in
1365        the compiled pattern. The size of memory for this was computed from the
1366        length of the subpattern and the repeat count. The latter is limited to
1367        65535, but there was no limit on the former, meaning that integer overflow
1368        could in principle occur. The compiled length of a repeated subpattern is
1369        now limited to 30,000 bytes in order to prevent this.
1371    12. Added the optional facility to have named substrings with the same name.
1373    13. Added the ability to use a named substring as a condition, using the
1374        Python syntax: (?(name)yes|no). This overloads (?(R)... and names that
1375        are numbers (not recommended). Forward references are permitted.
1377    14. Added forward references in named backreferences (if you see what I mean).
1379    15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the
1380        pattern could run off the end of the subject. For example, the pattern
1381        "(?s)(.{1,5})"8 did this with the subject "ab".
1383    16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if
1384        PCRE_CASELESS was set when matching characters that were quantified with ?
1385        or *.
1387    17. A character class other than a single negated character that had a minimum
1388        but no maximum quantifier - for example [ab]{6,} - was not handled
1389        correctly by pce_dfa_exec(). It would match only one character.
1391    18. A valid (though odd) pattern that looked like a POSIX character
1392        class but used an invalid character after [ (for example [[,abc,]]) caused
1393        pcre_compile() to give the error "Failed: internal error: code overflow" or
1394        in some cases to crash with a glibc free() error. This could even happen if
1395        the pattern terminated after [[ but there just happened to be a sequence of
1396        letters, a binary zero, and a closing ] in the memory that followed.
1398    19. Perl's treatment of octal escapes in the range \400 to \777 has changed
1399        over the years. Originally (before any Unicode support), just the bottom 8
1400        bits were taken. Thus, for example, \500 really meant \100. Nowadays the
1401        output from "man perlunicode" includes this:
1403          The regular expression compiler produces polymorphic opcodes.  That
1404          is, the pattern adapts to the data and automatically switches to
1405          the Unicode character scheme when presented with Unicode data--or
1406          instead uses a traditional byte scheme when presented with byte
1407          data.
1409        Sadly, a wide octal escape does not cause a switch, and in a string with
1410        no other multibyte characters, these octal escapes are treated as before.
1411        Thus, in Perl, the pattern  /\500/ actually matches \100 but the pattern
1412        /\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a
1413        Unicode string.
1415        I have not perpetrated such confusion in PCRE. Up till now, it took just
1416        the bottom 8 bits, as in old Perl. I have now made octal escapes with
1417        values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they
1418        translate to the appropriate multibyte character.
1420    29. Applied some refactoring to reduce the number of warnings from Microsoft
1421        and Borland compilers. This has included removing the fudge introduced
1422        seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused
1423        a warning about an unused variable.
1425    21. PCRE has not included VT (character 0x0b) in the set of whitespace
1426        characters since release 4.0, because Perl (from release 5.004) does not.
1427        [Or at least, is documented not to: some releases seem to be in conflict
1428        with the documentation.] However, when a pattern was studied with
1429        pcre_study() and all its branches started with \s, PCRE still included VT
1430        as a possible starting character. Of course, this did no harm; it just
1431        caused an unnecessary match attempt.
1433    22. Removed a now-redundant internal flag bit that recorded the fact that case
1434        dependency changed within the pattern. This was once needed for "required
1435        byte" processing, but is no longer used. This recovers a now-scarce options
1436        bit. Also moved the least significant internal flag bit to the most-
1437        significant bit of the word, which was not previously used (hangover from
1438        the days when it was an int rather than a uint) to free up another bit for
1439        the future.
1441    23. Added support for CRLF line endings as well as CR and LF. As well as the
1442        default being selectable at build time, it can now be changed at runtime
1443        via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to
1444        specify that it is scanning data with non-default line endings.
1446    24. Changed the definition of CXXLINK to make it agree with the definition of
1447        LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS.
1449    25. Applied Ian Taylor's patches to avoid using another stack frame for tail
1450        recursions. This makes a big different to stack usage for some patterns.
1452    26. If a subpattern containing a named recursion or subroutine reference such
1453        as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of
1454        the space required for the compiled pattern went wrong and gave too small a
1455        value. Depending on the environment, this could lead to "Failed: internal
1456        error: code overflow at offset 49" or "glibc detected double free or
1457        corruption" errors.
1459    27. Applied patches from Google (a) to support the new newline modes and (b) to
1460        advance over multibyte UTF-8 characters in GlobalReplace.
1462    28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a
1463        difference for some implementation of PCRE in some Windows version.
1465    29. Added some extra testing facilities to pcretest:
1467        \q<number>   in a data line sets the "match limit" value
1468        \Q<number>   in a data line sets the "match recursion limt" value
1469        -S <number>  sets the stack size, where <number> is in megabytes
1471        The -S option isn't available for Windows.
1474    Version 6.6 06-Feb-06
1475    ---------------------
1477     1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined
1478        in pcreposix.h. I have copied the definition from pcre.h.
1480     2. Change 25 for 6.5 broke compilation in a build directory out-of-tree
1481        because pcre.h is no longer a built file.
1483     3. Added Jeff Friedl's additional debugging patches to pcregrep. These are
1484        not normally included in the compiled code.
1487    Version 6.5 01-Feb-06
1488    ---------------------
1490     1. When using the partial match feature with pcre_dfa_exec(), it was not
1491        anchoring the second and subsequent partial matches at the new starting
1492        point. This could lead to incorrect results. For example, with the pattern
1493        /1234/, partially matching against "123" and then "a4" gave a match.
1495     2. Changes to pcregrep:
1497        (a) All non-match returns from pcre_exec() were being treated as failures
1498            to match the line. Now, unless the error is PCRE_ERROR_NOMATCH, an
1499            error message is output. Some extra information is given for the
1500            PCRE_ERROR_MATCHLIMIT and PCRE_ERROR_RECURSIONLIMIT errors, which are
1501            probably the only errors that are likely to be caused by users (by
1502            specifying a regex that has nested indefinite repeats, for instance).
1503            If there are more than 20 of these errors, pcregrep is abandoned.
1505        (b) A binary zero was treated as data while matching, but terminated the
1506            output line if it was written out. This has been fixed: binary zeroes
1507            are now no different to any other data bytes.
1509        (c) Whichever of the LC_ALL or LC_CTYPE environment variables is set is
1510            used to set a locale for matching. The --locale=xxxx long option has
1511            been added (no short equivalent) to specify a locale explicitly on the
1512            pcregrep command, overriding the environment variables.
1514        (d) When -B was used with -n, some line numbers in the output were one less
1515            than they should have been.
1517        (e) Added the -o (--only-matching) option.
1519        (f) If -A or -C was used with -c (count only), some lines of context were
1520            accidentally printed for the final match.
1522        (g) Added the -H (--with-filename) option.
1524        (h) The combination of options -rh failed to suppress file names for files
1525            that were found from directory arguments.
1527        (i) Added the -D (--devices) and -d (--directories) options.
1529        (j) Added the -F (--fixed-strings) option.
1531        (k) Allow "-" to be used as a file name for -f as well as for a data file.
1533        (l) Added the --colo(u)r option.
1535        (m) Added Jeffrey Friedl's -S testing option, but within #ifdefs so that it
1536            is not present by default.
1538     3. A nasty bug was discovered in the handling of recursive patterns, that is,
1539        items such as (?R) or (?1), when the recursion could match a number of
1540        alternatives. If it matched one of the alternatives, but subsequently,
1541        outside the recursion, there was a failure, the code tried to back up into
1542        the recursion. However, because of the way PCRE is implemented, this is not
1543        possible, and the result was an incorrect result from the match.
1545        In order to prevent this happening, the specification of recursion has
1546        been changed so that all such subpatterns are automatically treated as
1547        atomic groups. Thus, for example, (?R) is treated as if it were (?>(?R)).
1549     4. I had overlooked the fact that, in some locales, there are characters for
1550        which isalpha() is true but neither isupper() nor islower() are true. In
1551        the fr_FR locale, for instance, the \xAA and \xBA characters (ordmasculine
1552        and ordfeminine) are like this. This affected the treatment of \w and \W
1553        when they appeared in character classes, but not when they appeared outside
1554        a character class. The bit map for "word" characters is now created
1555        separately from the results of isalnum() instead of just taking it from the
1556        upper, lower, and digit maps. (Plus the underscore character, of course.)
1558     5. The above bug also affected the handling of POSIX character classes such as
1559        [[:alpha:]] and [[:alnum:]]. These do not have their own bit maps in PCRE's
1560        permanent tables. Instead, the bit maps for such a class were previously
1561        created as the appropriate unions of the upper, lower, and digit bitmaps.
1562        Now they are created by subtraction from the [[:word:]] class, which has
1563        its own bitmap.
1565     6. The [[:blank:]] character class matches horizontal, but not vertical space.
1566        It is created by subtracting the vertical space characters (\x09, \x0a,
1567        \x0b, \x0c) from the [[:space:]] bitmap. Previously, however, the
1568        subtraction was done in the overall bitmap for a character class, meaning
1569        that a class such as [\x0c[:blank:]] was incorrect because \x0c would not
1570        be recognized. This bug has been fixed.
1572     7. Patches from the folks at Google:
1574          (a) pcrecpp.cc: "to handle a corner case that may or may not happen in
1575          real life, but is still worth protecting against".
1577          (b) pcrecpp.cc: "corrects a bug when negative radixes are used with
1578          regular expressions".
1580          (c) pcre_scanner.cc: avoid use of std::count() because not all systems
1581          have it.
1583          (d) Split off pcrecpparg.h from pcrecpp.h and had the former built by
1584          "configure" and the latter not, in order to fix a problem somebody had
1585          with compiling the Arg class on HP-UX.
1587          (e) Improve the error-handling of the C++ wrapper a little bit.
1589          (f) New tests for checking recursion limiting.
1591     8. The pcre_memmove() function, which is used only if the environment does not
1592        have a standard memmove() function (and is therefore rarely compiled),
1593        contained two bugs: (a) use of int instead of size_t, and (b) it was not
1594        returning a result (though PCRE never actually uses the result).
1596     9. In the POSIX regexec() interface, if nmatch is specified as a ridiculously
1597        large number - greater than INT_MAX/(3*sizeof(int)) - REG_ESPACE is
1598        returned instead of calling malloc() with an overflowing number that would
1599        most likely cause subsequent chaos.
1601    10. The debugging option of pcretest was not showing the NO_AUTO_CAPTURE flag.
1603    11. The POSIX flag REG_NOSUB is now supported. When a pattern that was compiled
1604        with this option is matched, the nmatch and pmatch options of regexec() are
1605        ignored.
1607    12. Added REG_UTF8 to the POSIX interface. This is not defined by POSIX, but is
1608        provided in case anyone wants to the the POSIX interface with UTF-8
1609        strings.
1611    13. Added CXXLDFLAGS to the Makefile parameters to provide settings only on the
1612        C++ linking (needed for some HP-UX environments).
1614    14. Avoid compiler warnings in get_ucpname() when compiled without UCP support
1615        (unused parameter) and in the pcre_printint() function (omitted "default"
1616        switch label when the default is to do nothing).
1618    15. Added some code to make it possible, when PCRE is compiled as a C++
1619        library, to replace subject pointers for pcre_exec() with a smart pointer
1620        class, thus making it possible to process discontinuous strings.
1622    16. The two macros PCRE_EXPORT and PCRE_DATA_SCOPE are confusing, and perform
1623        much the same function. They were added by different people who were trying
1624        to make PCRE easy to compile on non-Unix systems. It has been suggested
1625        that PCRE_EXPORT be abolished now that there is more automatic apparatus
1626        for compiling on Windows systems. I have therefore replaced it with
1627        PCRE_DATA_SCOPE. This is set automatically for Windows; if not set it
1628        defaults to "extern" for C or "extern C" for C++, which works fine on
1629        Unix-like systems. It is now possible to override the value of PCRE_DATA_
1630        SCOPE with something explicit in config.h. In addition:
1632        (a) pcreposix.h still had just "extern" instead of either of these macros;
1633            I have replaced it with PCRE_DATA_SCOPE.
1635        (b) Functions such as _pcre_xclass(), which are internal to the library,
1636            but external in the C sense, all had PCRE_EXPORT in their definitions.
1637            This is apparently wrong for the Windows case, so I have removed it.
1638            (It makes no difference on Unix-like systems.)
1640    17. Added a new limit, MATCH_LIMIT_RECURSION, which limits the depth of nesting
1641        of recursive calls to match(). This is different to MATCH_LIMIT because
1642        that limits the total number of calls to match(), not all of which increase
1643        the depth of recursion. Limiting the recursion depth limits the amount of
1644        stack (or heap if NO_RECURSE is set) that is used. The default can be set
1645        when PCRE is compiled, and changed at run time. A patch from Google adds
1646        this functionality to the C++ interface.
1648    18. Changes to the handling of Unicode character properties:
1650        (a) Updated the table to Unicode 4.1.0.
1652        (b) Recognize characters that are not in the table as "Cn" (undefined).
1654        (c) I revised the way the table is implemented to a much improved format
1655            which includes recognition of ranges. It now supports the ranges that
1656            are defined in UnicodeData.txt, and it also amalgamates other
1657            characters into ranges. This has reduced the number of entries in the
1658            table from around 16,000 to around 3,000, thus reducing its size
1659            considerably. I realized I did not need to use a tree structure after
1660            all - a binary chop search is just as efficient. Having reduced the
1661            number of entries, I extended their size from 6 bytes to 8 bytes to
1662            allow for more data.
1664        (d) Added support for Unicode script names via properties such as \p{Han}.
1666    19. In UTF-8 mode, a backslash followed by a non-Ascii character was not
1667        matching that character.
1669    20. When matching a repeated Unicode property with a minimum greater than zero,
1670        (for example \pL{2,}), PCRE could look past the end of the subject if it
1671        reached it while seeking the minimum number of characters. This could
1672        happen only if some of the characters were more than one byte long, because
1673        there is a check for at least the minimum number of bytes.
1675    21. Refactored the implementation of \p and \P so as to be more general, to
1676        allow for more different types of property in future. This has changed the
1677        compiled form incompatibly. Anybody with saved compiled patterns that use
1678        \p or \P will have to recompile them.
1680    22. Added "Any" and "L&" to the supported property types.
1682    23. Recognize \x{...} as a code point specifier, even when not in UTF-8 mode,
1683        but give a compile time error if the value is greater than 0xff.
1685    24. The man pages for pcrepartial, pcreprecompile, and pcre_compile2 were
1686        accidentally not being installed or uninstalled.
1688    25. The pcre.h file was built from pcre.h.in, but the only changes that were
1689        made were to insert the current release number. This seemed silly, because
1690        it made things harder for people building PCRE on systems that don't run
1691        "configure". I have turned pcre.h into a distributed file, no longer built
1692        by "configure", with the version identification directly included. There is
1693        no longer a pcre.h.in file.
1695        However, this change necessitated a change to the pcre-config script as
1696        well. It is built from pcre-config.in, and one of the substitutions was the
1697        release number. I have updated configure.ac so that ./configure now finds
1698        the release number by grepping pcre.h.
1700    26. Added the ability to run the tests under valgrind.
1703    Version 6.4 05-Sep-05
1704    ---------------------
1706     1. Change 6.0/10/(l) to pcregrep introduced a bug that caused separator lines
1707        "--" to be printed when multiple files were scanned, even when none of the
1708        -A, -B, or -C options were used. This is not compatible with Gnu grep, so I
1709        consider it to be a bug, and have restored the previous behaviour.
1711     2. A couple of code tidies to get rid of compiler warnings.
1713     3. The pcretest program used to cheat by referring to symbols in the library
1714        whose names begin with _pcre_. These are internal symbols that are not
1715        really supposed to be visible externally, and in some environments it is
1716        possible to suppress them. The cheating is now confined to including
1717        certain files from the library's source, which is a bit cleaner.
1719     4. Renamed pcre.in as pcre.h.in to go with pcrecpp.h.in; it also makes the
1720        file's purpose clearer.
1722     5. Reorganized pcre_ucp_findchar().
1725    Version 6.3 15-Aug-05
1726    ---------------------
1728     1. The file libpcre.pc.in did not have general read permission in the tarball.
1730     2. There were some problems when building without C++ support:
1732        (a) If C++ support was not built, "make install" and "make test" still
1733            tried to test it.
1735        (b) There were problems when the value of CXX was explicitly set. Some
1736            changes have been made to try to fix these, and ...
1738        (c) --disable-cpp can now be used to explicitly disable C++ support.
1740        (d) The use of @CPP_OBJ@ directly caused a blank line preceded by a
1741            backslash in a target when C++ was disabled. This confuses some
1742            versions of "make", apparently. Using an intermediate variable solves
1743            this. (Same for CPP_LOBJ.)
1745     3. $(LINK_FOR_BUILD) now includes $(CFLAGS_FOR_BUILD) and $(LINK)
1746        (non-Windows) now includes $(CFLAGS) because these flags are sometimes
1747        necessary on certain architectures.
1749     4. Added a setting of -export-symbols-regex to the link command to remove
1750        those symbols that are exported in the C sense, but actually are local
1751        within the library, and not documented. Their names all begin with
1752        "_pcre_". This is not a perfect job, because (a) we have to except some
1753        symbols that pcretest ("illegally") uses, and (b) the facility isn't always
1754        available (and never for static libraries). I have made a note to try to
1755        find a way round (a) in the future.
1758    Version 6.2 01-Aug-05
1759    ---------------------
1761     1. There was no test for integer overflow of quantifier values. A construction
1762        such as {1111111111111111} would give undefined results. What is worse, if
1763        a minimum quantifier for a parenthesized subpattern overflowed and became
1764        negative, the calculation of the memory size went wrong. This could have
1765        led to memory overwriting.
1767     2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
1769     3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
1770        operating environments where this matters.
1772     4. Applied Giuseppe Maxia's patch to add additional features for controlling
1773        PCRE options from within the C++ wrapper.
1775     5. Named capturing subpatterns were not being correctly counted when a pattern
1776        was compiled. This caused two problems: (a) If there were more than 100
1777        such subpatterns, the calculation of the memory needed for the whole
1778        compiled pattern went wrong, leading to an overflow error. (b) Numerical
1779        back references of the form \12, where the number was greater than 9, were
1780        not recognized as back references, even though there were sufficient
1781        previous subpatterns.
1783     6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
1784        versions of gcc, e.g. 2.95.4.
1787    Version 6.1 21-Jun-05
1788    ---------------------
1790     1. There was one reference to the variable "posix" in pcretest.c that was not
1791        surrounded by "#if !defined NOPOSIX".
1793     2. Make it possible to compile pcretest without DFA support, UTF8 support, or
1794        the cross-check on the old pcre_info() function, for the benefit of the
1795        cut-down version of PCRE that is currently imported into Exim.
1797     3. A (silly) pattern starting with (?i)(?-i) caused an internal space
1798        allocation error. I've done the easy fix, which wastes 2 bytes for sensible
1799        patterns that start (?i) but I don't think that matters. The use of (?i) is
1800        just an example; this all applies to the other options as well.
1802     4. Since libtool seems to echo the compile commands it is issuing, the output
1803        from "make" can be reduced a bit by putting "@" in front of each libtool
1804        compile command.
1806     5. Patch from the folks at Google for configure.in to be a bit more thorough
1807        in checking for a suitable C++ installation before trying to compile the
1808        C++ stuff. This should fix a reported problem when a compiler was present,
1809        but no suitable headers.
1811     6. The man pages all had just "PCRE" as their title. I have changed them to
1812        be the relevant file name. I have also arranged that these names are
1813        retained in the file doc/pcre.txt, which is a concatenation in text format
1814        of all the man pages except the little individual ones for each function.
1816     7. The NON-UNIX-USE file had not been updated for the different set of source
1817        files that come with release 6. I also added a few comments about the C++
1818        wrapper.
1821    Version 6.0 07-Jun-05
1822    ---------------------
1824     1. Some minor internal re-organization to help with my DFA experiments.
1826     2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
1827        didn't matter for the library itself when fully configured, but did matter
1828        when compiling without UCP support, or within Exim, where the ucp files are
1829        not imported.
1831     3. Refactoring of the library code to split up the various functions into
1832        different source modules. The addition of the new DFA matching code (see
1833        below) to a single monolithic source would have made it really too
1834        unwieldy, quite apart from causing all the code to be include in a
1835        statically linked application, when only some functions are used. This is
1836        relevant even without the DFA addition now that patterns can be compiled in
1837        one application and matched in another.
1839        The downside of splitting up is that there have to be some external
1840        functions and data tables that are used internally in different modules of
1841        the library but which are not part of the API. These have all had their
1842        names changed to start with "_pcre_" so that they are unlikely to clash
1843        with other external names.
1845     4. Added an alternate matching function, pcre_dfa_exec(), which matches using
1846        a different (DFA) algorithm. Although it is slower than the original
1847        function, it does have some advantages for certain types of matching
1848        problem.
1850     5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
1851        including restarting after a partial match.
1853     6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
1854        defined when compiling for Windows was sent to me. I have put it into the
1855        code, though I have no means of testing or verifying it.
1857     7. Added the pcre_refcount() auxiliary function.
1859     8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
1860        match before or at the first newline in the subject string. In pcretest,
1861        the /f option on a pattern can be used to set this.
1863     9. A repeated \w when used in UTF-8 mode with characters greater than 256
1864        would behave wrongly. This has been present in PCRE since release 4.0.
1866    10. A number of changes to the pcregrep command:
1868        (a) Refactored how -x works; insert ^(...)$ instead of setting
1869            PCRE_ANCHORED and checking the length, in preparation for adding
1870            something similar for -w.
1872        (b) Added the -w (match as a word) option.
1874        (c) Refactored the way lines are read and buffered so as to have more
1875            than one at a time available.
1877        (d) Implemented a pcregrep test script.
1879        (e) Added the -M (multiline match) option. This allows patterns to match
1880            over several lines of the subject. The buffering ensures that at least
1881            8K, or the rest of the document (whichever is the shorter) is available
1882            for matching (and similarly the previous 8K for lookbehind assertions).
1884        (f) Changed the --help output so that it now says
1886              -w, --word-regex(p)
1888            instead of two lines, one with "regex" and the other with "regexp"
1889            because that confused at least one person since the short forms are the
1890            same. (This required a bit of code, as the output is generated
1891            automatically from a table. It wasn't just a text change.)
1893        (g) -- can be used to terminate pcregrep options if the next thing isn't an
1894            option but starts with a hyphen. Could be a pattern or a path name
1895            starting with a hyphen, for instance.
1897        (h) "-" can be given as a file name to represent stdin.
1899        (i) When file names are being printed, "(standard input)" is used for
1900            the standard input, for compatibility with GNU grep. Previously
1901            "<stdin>" was used.
1903        (j) The option --label=xxx can be used to supply a name to be used for
1904            stdin when file names are being printed. There is no short form.
1906        (k) Re-factored the options decoding logic because we are going to add
1907            two more options that take data. Such options can now be given in four
1908            different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
1910        (l) Added the -A, -B, and -C options for requesting that lines of context
1911            around matches be printed.
1913        (m) Added the -L option to print the names of files that do not contain
1914            any matching lines, that is, the complement of -l.
1916        (n) The return code is 2 if any file cannot be opened, but pcregrep does
1917            continue to scan other files.
1919        (o) The -s option was incorrectly implemented. For compatibility with other
1920            greps, it now suppresses the error message for a non-existent or non-
1921            accessible file (but not the return code). There is a new option called
1922            -q that suppresses the output of matching lines, which was what -s was
1923            previously doing.
1925        (p) Added --include and --exclude options to specify files for inclusion
1926            and exclusion when recursing.
1928    11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
1929        Hopefully, it now does.
1931    12. Missing cast in pcre_study().
1933    13. Added an "uninstall" target to the makefile.
1935    14. Replaced "extern" in the function prototypes in Makefile.in with
1936        "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
1937        world, but is set differently for Windows.
1939    15. Added a second compiling function called pcre_compile2(). The only
1940        difference is that it has an extra argument, which is a pointer to an
1941        integer error code. When there is a compile-time failure, this is set
1942        non-zero, in addition to the error test pointer being set to point to an
1943        error message. The new argument may be NULL if no error number is required
1944        (but then you may as well call pcre_compile(), which is now just a
1945        wrapper). This facility is provided because some applications need a
1946        numeric error indication, but it has also enabled me to tidy up the way
1947        compile-time errors are handled in the POSIX wrapper.
1949    16. Added VPATH=.libs to the makefile; this should help when building with one
1950        prefix path and installing with another. (Or so I'm told by someone who
1951        knows more about this stuff than I do.)
1953    17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
1954        passes PCRE_DOTALL to the pcre_compile() function, making the "." character
1955        match everything, including newlines. This is not POSIX-compatible, but
1956        somebody wanted the feature. From pcretest it can be activated by using
1957        both the P and the s flags.
1959    18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
1961    19. libpcre.pc was being incorrectly installed as executable.
1963    20. A couple of places in pcretest check for end-of-line by looking for '\n';
1964        it now also looks for '\r' so that it will work unmodified on Windows.
1966    21. Added Google's contributed C++ wrapper to the distribution.
1968    22. Added some untidy missing memory free() calls in pcretest, to keep
1969        Electric Fence happy when testing.
1973    Version 5.0 13-Sep-04
1974    ---------------------
1976     1. Internal change: literal characters are no longer packed up into items
1977        containing multiple characters in a single byte-string. Each character
1978        is now matched using a separate opcode. However, there may be more than one
1979        byte in the character in UTF-8 mode.
1981     2. The pcre_callout_block structure has two new fields: pattern_position and
1982        next_item_length. These contain the offset in the pattern to the next match
1983        item, and its length, respectively.
1985     3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
1986        insertion of callouts before each pattern item. Added the /C option to
1987        pcretest to make use of this.
1989     4. On the advice of a Windows user, the lines
1991          #if defined(_WIN32) || defined(WIN32)
1992          _setmode( _fileno( stdout ), 0x8000 );
1993          #endif  /* defined(_WIN32) || defined(WIN32) */
1995        have been added to the source of pcretest. This apparently does useful
1996        magic in relation to line terminators.
1998     5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
1999        for the benefit of those environments where the "b" makes a difference.
2001     6. The icc compiler has the same options as gcc, but "configure" doesn't seem
2002        to know about it. I have put a hack into configure.in that adds in code
2003        to set GCC=yes if CC=icc. This seems to end up at a point in the
2004        generated configure script that is early enough to affect the setting of
2005        compiler options, which is what is needed, but I have no means of testing
2006        whether it really works. (The user who reported this had patched the
2007        generated configure script, which of course I cannot do.)
2009        LATER: After change 22 below (new libtool files), the configure script
2010        seems to know about icc (and also ecc). Therefore, I have commented out
2011        this hack in configure.in.
2013     7. Added support for pkg-config (2 patches were sent in).
2015     8. Negated POSIX character classes that used a combination of internal tables
2016        were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
2017        [[:^ascii]]. Typically, they would match almost any characters. The other
2018        POSIX classes were not broken in this way.
2020     9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
2021        to find the match, as PCRE was deluded into thinking that the match had to
2022        start at the start point or following a newline. The same bug applied to
2023        patterns with negative forward assertions or any backward assertions
2024        preceding ".*" at the start, unless the pattern required a fixed first
2025        character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
2027    10. In UTF-8 mode, when moving forwards in the subject after a failed match
2028        starting at the last subject character, bytes beyond the end of the subject
2029        string were read.
2031    11. Renamed the variable "class" as "classbits" to make life easier for C++
2032        users. (Previously there was a macro definition, but it apparently wasn't
2033        enough.)
2035    12. Added the new field "tables" to the extra data so that tables can be passed
2036        in at exec time, or the internal tables can be re-selected. This allows
2037        a compiled regex to be saved and re-used at a later time by a different
2038        program that might have everything at different addresses.
2040    13. Modified the pcre-config script so that, when run on Solaris, it shows a
2041        -R library as well as a -L library.
2043    14. The debugging options of pcretest (-d on the command line or D on a
2044        pattern) showed incorrect output for anything following an extended class
2045        that contained multibyte characters and which was followed by a quantifier.
2047    15. Added optional support for general category Unicode character properties
2048        via the \p, \P, and \X escapes. Unicode property support implies UTF-8
2049        support. It adds about 90K to the size of the library. The meanings of the
2050        inbuilt class escapes such as \d and \s have NOT been changed.
2052    16. Updated pcredemo.c to include calls to free() to release the memory for the
2053        compiled pattern.
2055    17. The generated file chartables.c was being created in the source directory
2056        instead of in the building directory. This caused the build to fail if the
2057        source directory was different from the building directory, and was
2058        read-only.
2060    18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
2061        file. No doubt somebody will tell me if they don't make sense... Also added
2062        Dan Mooney's comments about building on OpenVMS.
2064    19. Added support for partial matching via the PCRE_PARTIAL option for
2065        pcre_exec() and the \P data escape in pcretest.
2067    20. Extended pcretest with 3 new pattern features:
2069        (i)   A pattern option of the form ">rest-of-line" causes pcretest to
2070              write the compiled pattern to the file whose name is "rest-of-line".
2071              This is a straight binary dump of the data, with the saved pointer to
2072              the character tables forced to be NULL. The study data, if any, is
2073              written too. After writing, pcretest reads a new pattern.
2075        (ii)  If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
2076              compiled pattern from the given file. There must not be any
2077              occurrences of "<" in the file name (pretty unlikely); if there are,
2078              pcretest will instead treat the initial "<" as a pattern delimiter.
2079              After reading in the pattern, pcretest goes on to read data lines as
2080              usual.
2082        (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
2083              and 16-bit fields in a compiled pattern, to simulate a pattern that
2084              was compiled on a host of opposite endianness.
2086    21. The pcre-exec() function can now cope with patterns that were compiled on
2087        hosts of opposite endianness, with this restriction:
2089          As for any compiled expression that is saved and used later, the tables
2090          pointer field cannot be preserved; the extra_data field in the arguments
2091          to pcre_exec() should be used to pass in a tables address if a value
2092          other than the default internal tables were used at compile time.
2094    22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
2095        now diagnosed as an error. Previously, most of the time, a negative number
2096        would have been treated as zero, but if in addition "ovector" was passed as
2097        NULL, a crash could occur.
2099    23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
2100        new versions from the libtool 1.5 distribution (the last one is a copy of
2101        a file called libtool.m4). This seems to have fixed the need to patch
2102        "configure" to support Darwin 1.3 (which I used to do). However, I still
2103        had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
2104        workstation).
2106    24. Changed the PCRE licence to be the more standard "BSD" licence.
2109  Version 4.5 01-Dec-03  Version 4.5 01-Dec-03
2110  ---------------------  ---------------------

Removed from v.73  
changed lines
  Added in v.428

  ViewVC Help
Powered by ViewVC 1.1.5