/[pcre]/code/trunk/ChangeLog
ViewVC logotype

Diff of /code/trunk/ChangeLog

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

revision 248 by ph10, Mon Sep 17 10:09:22 2007 UTC revision 1040 by zherczeg, Sun Sep 16 06:52:27 2012 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 7.4 10-Sep-07  Version 8.32
5    ------------
6    
7    1.  Improved JIT compiler optimizations for first character search and single
8        character iterators.
9    
10    2.  Supporting IBM XL C compilers for PPC architectures in the JIT compiler.
11        Patch by Daniel Richard G.
12    
13    3.  Single character iterator optimizations in the JIT compiler.
14    
15    4.  Improved JIT compiler optimizations for character ranges.
16    
17    5.  Rename the "leave" variable names to "quit" to improve WinCE compatibility.
18        Reported by Giuseppe D'Angelo.
19    
20    6.  The PCRE_STARTLINE bit, indicating that a match can occur only at the start
21        of a line, was being set incorrectly in cases where .* appeared inside
22        atomic brackets at the start of a pattern, or where there was a subsequent
23        *PRUNE or *SKIP.
24    
25    7.  Improved instruction cache flush for POWER/PowerPC.
26        Patch by Daniel Richard G.
27    
28    8.  Fixed a number of issues in pcregrep, making it more compatible with GNU
29        grep:
30    
31        (a) There is now no limit to the number of patterns to be matched.
32    
33        (b) An error is given if a pattern is too long.
34    
35        (c) Multiple uses of --exclude, --exclude-dir, --include, and --include-dir
36            are now supported.
37    
38        (d) --exclude-from and --include-from (multiple use) have been added.
39    
40        (e) Exclusions and inclusions now apply to all files and directories, not
41            just to those obtained from scanning a directory recursively.
42    
43        (f) Multiple uses of -f and --file-list are now supported.
44    
45        (g) In a Windows environment, the default for -d has been changed from
46            "read" (the GNU grep default) to "skip", because otherwise the presence
47            of a directory in the file list provokes an error.
48    
49        (h) The documentation has been revised and clarified in places.
50    
51    9.  Improve the matching speed of capturing brackets.
52    
53    10. Changed the meaning of \X so that it now matches a Unicode extended
54        grapheme cluster.
55    
56    11. Patch by Daniel Richard G to the autoconf files to add a macro for sorting
57        out POSIX threads when JIT support is configured.
58    
59    12. Added support for PCRE_STUDY_EXTRA_NEEDED.
60    
61    13. In the POSIX wrapper regcomp() function, setting re_nsub field in the preg
62        structure could go wrong in environments where size_t is not the same size
63        as int.
64    
65    14. Applied user-supplied patch to pcrecpp.cc to allow PCRE_NO_UTF8_CHECK to be
66        set.
67    
68    15. The EBCDIC support had decayed; later updates to the code had included
69        explicit references to (e.g.) \x0a instead of CHAR_LF. There has been a
70        general tidy up of EBCDIC-related issues, and the documentation was also
71        not quite right. There is now a test that can be run on ASCII systems to
72        check some of the EBCDIC-related things (but is it not a full test).
73    
74    16. The new PCRE_STUDY_EXTRA_NEEDED option is now used by pcregrep, resulting
75        in a small tidy to the code.
76    
77    17. Fix JIT tests when UTF is disabled and both 8 and 16 bit mode are enabled.
78    
79    18. If the --only-matching (-o) option in pcregrep is specified multiple
80        times, each one causes appropriate output. For example, -o1 -o2 outputs the
81        substrings matched by the 1st and 2nd capturing parentheses. A separating
82        string can be specified by --om-separator (default empty).
83    
84    19. Improving the first n character searches.
85    
86    
87    Version 8.31 06-July-2012
88    -------------------------
89    
90    1.  Fixing a wrong JIT test case and some compiler warnings.
91    
92    2.  Removed a bashism from the RunTest script.
93    
94    3.  Add a cast to pcre_exec.c to fix the warning "unary minus operator applied
95        to unsigned type, result still unsigned" that was given by an MS compiler
96        on encountering the code "-sizeof(xxx)".
97    
98    4.  Partial matching support is added to the JIT compiler.
99    
100    5.  Fixed several bugs concerned with partial matching of items that consist
101        of more than one character:
102    
103        (a) /^(..)\1/ did not partially match "aba" because checking references was
104            done on an "all or nothing" basis. This also applied to repeated
105            references.
106    
107        (b) \R did not give a hard partial match if \r was found at the end of the
108            subject.
109    
110        (c) \X did not give a hard partial match after matching one or more
111            characters at the end of the subject.
112    
113        (d) When newline was set to CRLF, a pattern such as /a$/ did not recognize
114            a partial match for the string "\r".
115    
116        (e) When newline was set to CRLF, the metacharacter "." did not recognize
117            a partial match for a CR character at the end of the subject string.
118    
119    6.  If JIT is requested using /S++ or -s++ (instead of just /S+ or -s+) when
120        running pcretest, the text "(JIT)" added to the output whenever JIT is
121        actually used to run the match.
122    
123    7.  Individual JIT compile options can be set in pcretest by following -s+[+]
124        or /S+[+] with a digit between 1 and 7.
125    
126    8.  OP_NOT now supports any UTF character not just single-byte ones.
127    
128    9.  (*MARK) control verb is now supported by the JIT compiler.
129    
130    10. The command "./RunTest list" lists the available tests without actually
131        running any of them. (Because I keep forgetting what they all are.)
132    
133    11. Add PCRE_INFO_MAXLOOKBEHIND.
134    
135    12. Applied a (slightly modified) user-supplied patch that improves performance
136        when the heap is used for recursion (compiled with --disable-stack-for-
137        recursion). Instead of malloc and free for each heap frame each time a
138        logical recursion happens, frames are retained on a chain and re-used where
139        possible. This sometimes gives as much as 30% improvement.
140    
141    13. As documented, (*COMMIT) is now confined to within a recursive subpattern
142        call.
143    
144    14. As documented, (*COMMIT) is now confined to within a positive assertion.
145    
146    15. It is now possible to link pcretest with libedit as an alternative to
147        libreadline.
148    
149    16. (*COMMIT) control verb is now supported by the JIT compiler.
150    
151    17. The Unicode data tables have been updated to Unicode 6.1.0.
152    
153    18. Added --file-list option to pcregrep.
154    
155    19. Added binary file support to pcregrep, including the -a, --binary-files,
156        -I, and --text options.
157    
158    20. The madvise function is renamed for posix_madvise for QNX compatibility
159        reasons. Fixed by Giuseppe D'Angelo.
160    
161    21. Fixed a bug for backward assertions with REVERSE 0 in the JIT compiler.
162    
163    22. Changed the option for creating symbolic links for 16-bit man pages from
164        -s to -sf so that re-installing does not cause issues.
165    
166    23. Support PCRE_NO_START_OPTIMIZE in JIT as (*MARK) support requires it.
167    
168    24. Fixed a very old bug in pcretest that caused errors with restarted DFA
169        matches in certain environments (the workspace was not being correctly
170        retained). Also added to pcre_dfa_exec() a simple plausibility check on
171        some of the workspace data at the beginning of a restart.
172    
173    25. \s*\R was auto-possessifying the \s* when it should not, whereas \S*\R
174        was not doing so when it should - probably a typo introduced by SVN 528
175        (change 8.10/14).
176    
177    26. When PCRE_UCP was not set, \w+\x{c4} was incorrectly auto-possessifying the
178        \w+ when the character tables indicated that \x{c4} was a word character.
179        There were several related cases, all because the tests for doing a table
180        lookup were testing for characters less than 127 instead of 255.
181    
182    27. If a pattern contains capturing parentheses that are not used in a match,
183        their slots in the ovector are set to -1. For those that are higher than
184        any matched groups, this happens at the end of processing. In the case when
185        there were back references that the ovector was too small to contain
186        (causing temporary malloc'd memory to be used during matching), and the
187        highest capturing number was not used, memory off the end of the ovector
188        was incorrectly being set to -1. (It was using the size of the temporary
189        memory instead of the true size.)
190    
191    28. To catch bugs like 27 using valgrind, when pcretest is asked to specify an
192        ovector size, it uses memory at the end of the block that it has got.
193    
194    29. Check for an overlong MARK name and give an error at compile time. The
195        limit is 255 for the 8-bit library and 65535 for the 16-bit library.
196    
197    30. JIT compiler update.
198    
199    31. JIT is now supported on jailbroken iOS devices. Thanks for Ruiger
200        Rill for the patch.
201    
202    32. Put spaces around SLJIT_PRINT_D in the JIT compiler. Required by CXX11.
203    
204    33. Variable renamings in the PCRE-JIT compiler. No functionality change.
205    
206    34. Fixed typos in pcregrep: in two places there was SUPPORT_LIBZ2 instead of
207        SUPPORT_LIBBZ2. This caused a build problem when bzip2 but not gzip (zlib)
208        was enabled.
209    
210    35. Improve JIT code generation for greedy plus quantifier.
211    
212    36. When /((?:a?)*)*c/ or /((?>a?)*)*c/ was matched against "aac", it set group
213        1 to "aa" instead of to an empty string. The bug affected repeated groups
214        that could potentially match an empty string.
215    
216    37. Optimizing single character iterators in JIT.
217    
218    38. Wide characters specified with \uxxxx in JavaScript mode are now subject to
219        the same checks as \x{...} characters in non-JavaScript mode. Specifically,
220        codepoints that are too big for the mode are faulted, and in a UTF mode,
221        disallowed codepoints are also faulted.
222    
223    39. If PCRE was compiled with UTF support, in three places in the DFA
224        matcher there was code that should only have been obeyed in UTF mode, but
225        was being obeyed unconditionally. In 8-bit mode this could cause incorrect
226        processing when bytes with values greater than 127 were present. In 16-bit
227        mode the bug would be provoked by values in the range 0xfc00 to 0xdc00. In
228        both cases the values are those that cannot be the first data item in a UTF
229        character. The three items that might have provoked this were recursions,
230        possessively repeated groups, and atomic groups.
231    
232    40. Ensure that libpcre is explicitly listed in the link commands for pcretest
233        and pcregrep, because some OS require shared objects to be explicitly
234        passed to ld, causing the link step to fail if they are not.
235    
236    41. There were two incorrect #ifdefs in pcre_study.c, meaning that, in 16-bit
237        mode, patterns that started with \h* or \R* might be incorrectly matched.
238    
239    
240    Version 8.30 04-February-2012
241    -----------------------------
242    
243    1.  Renamed "isnumber" as "is_a_number" because in some Mac environments this
244        name is defined in ctype.h.
245    
246    2.  Fixed a bug in fixed-length calculation for lookbehinds that would show up
247        only in quite long subpatterns.
248    
249    3.  Removed the function pcre_info(), which has been obsolete and deprecated
250        since it was replaced by pcre_fullinfo() in February 2000.
251    
252    4.  For a non-anchored pattern, if (*SKIP) was given with a name that did not
253        match a (*MARK), and the match failed at the start of the subject, a
254        reference to memory before the start of the subject could occur. This bug
255        was introduced by fix 17 of release 8.21.
256    
257    5.  A reference to an unset group with zero minimum repetition was giving
258        totally wrong answers (in non-JavaScript-compatibility mode). For example,
259        /(another)?(\1?)test/ matched against "hello world test". This bug was
260        introduced in release 8.13.
261    
262    6.  Add support for 16-bit character strings (a large amount of work involving
263        many changes and refactorings).
264    
265    7.  RunGrepTest failed on msys because \r\n was replaced by whitespace when the
266        command "pattern=`printf 'xxx\r\njkl'`" was run. The pattern is now taken
267        from a file.
268    
269    8.  Ovector size of 2 is also supported by JIT based pcre_exec (the ovector size
270        rounding is not applied in this particular case).
271    
272    9.  The invalid Unicode surrogate codepoints U+D800 to U+DFFF are now rejected
273        if they appear, or are escaped, in patterns.
274    
275    10. Get rid of a number of -Wunused-but-set-variable warnings.
276    
277    11. The pattern /(?=(*:x))(q|)/ matches an empty string, and returns the mark
278        "x". The similar pattern /(?=(*:x))((*:y)q|)/ did not return a mark at all.
279        Oddly, Perl behaves the same way. PCRE has been fixed so that this pattern
280        also returns the mark "x". This bug applied to capturing parentheses,
281        non-capturing parentheses, and atomic parentheses. It also applied to some
282        assertions.
283    
284    12. Stephen Kelly's patch to CMakeLists.txt allows it to parse the version
285        information out of configure.ac instead of relying on pcre.h.generic, which
286        is not stored in the repository.
287    
288    13. Applied Dmitry V. Levin's patch for a more portable method for linking with
289        -lreadline.
290    
291    14. ZH added PCRE_CONFIG_JITTARGET; added its output to pcretest -C.
292    
293    15. Applied Graycode's patch to put the top-level frame on the stack rather
294        than the heap when not using the stack for recursion. This gives a
295        performance improvement in many cases when recursion is not deep.
296    
297    16. Experimental code added to "pcretest -C" to output the stack frame size.
298    
299    
300    Version 8.21 12-Dec-2011
301    ------------------------
302    
303    1.  Updating the JIT compiler.
304    
305    2.  JIT compiler now supports OP_NCREF, OP_RREF and OP_NRREF. New test cases
306        are added as well.
307    
308    3.  Fix cache-flush issue on PowerPC (It is still an experimental JIT port).
309        PCRE_EXTRA_TABLES is not suported by JIT, and should be checked before
310        calling _pcre_jit_exec. Some extra comments are added.
311    
312    4.  (*MARK) settings inside atomic groups that do not contain any capturing
313        parentheses, for example, (?>a(*:m)), were not being passed out. This bug
314        was introduced by change 18 for 8.20.
315    
316    5.  Supporting of \x, \U and \u in JavaScript compatibility mode based on the
317        ECMA-262 standard.
318    
319    6.  Lookbehinds such as (?<=a{2}b) that contained a fixed repetition were
320        erroneously being rejected as "not fixed length" if PCRE_CASELESS was set.
321        This bug was probably introduced by change 9 of 8.13.
322    
323    7.  While fixing 6 above, I noticed that a number of other items were being
324        incorrectly rejected as "not fixed length". This arose partly because newer
325        opcodes had not been added to the fixed-length checking code. I have (a)
326        corrected the bug and added tests for these items, and (b) arranged for an
327        error to occur if an unknown opcode is encountered while checking for fixed
328        length instead of just assuming "not fixed length". The items that were
329        rejected were: (*ACCEPT), (*COMMIT), (*FAIL), (*MARK), (*PRUNE), (*SKIP),
330        (*THEN), \h, \H, \v, \V, and single character negative classes with fixed
331        repetitions, e.g. [^a]{3}, with and without PCRE_CASELESS.
332    
333    8.  A possessively repeated conditional subpattern such as (?(?=c)c|d)++ was
334        being incorrectly compiled and would have given unpredicatble results.
335    
336    9.  A possessively repeated subpattern with minimum repeat count greater than
337        one behaved incorrectly. For example, (A){2,}+ behaved as if it was
338        (A)(A)++ which meant that, after a subsequent mismatch, backtracking into
339        the first (A) could occur when it should not.
340    
341    10. Add a cast and remove a redundant test from the code.
342    
343    11. JIT should use pcre_malloc/pcre_free for allocation.
344    
345    12. Updated pcre-config so that it no longer shows -L/usr/lib, which seems
346        best practice nowadays, and helps with cross-compiling. (If the exec_prefix
347        is anything other than /usr, -L is still shown).
348    
349    13. In non-UTF-8 mode, \C is now supported in lookbehinds and DFA matching.
350    
351    14. Perl does not support \N without a following name in a [] class; PCRE now
352        also gives an error.
353    
354    15. If a forward reference was repeated with an upper limit of around 2000,
355        it caused the error "internal error: overran compiling workspace". The
356        maximum number of forward references (including repeats) was limited by the
357        internal workspace, and dependent on the LINK_SIZE. The code has been
358        rewritten so that the workspace expands (via pcre_malloc) if necessary, and
359        the default depends on LINK_SIZE. There is a new upper limit (for safety)
360        of around 200,000 forward references. While doing this, I also speeded up
361        the filling in of repeated forward references.
362    
363    16. A repeated forward reference in a pattern such as (a)(?2){2}(.) was
364        incorrectly expecting the subject to contain another "a" after the start.
365    
366    17. When (*SKIP:name) is activated without a corresponding (*MARK:name) earlier
367        in the match, the SKIP should be ignored. This was not happening; instead
368        the SKIP was being treated as NOMATCH. For patterns such as
369        /A(*MARK:A)A+(*SKIP:B)Z|AAC/ this meant that the AAC branch was never
370        tested.
371    
372    18. The behaviour of (*MARK), (*PRUNE), and (*THEN) has been reworked and is
373        now much more compatible with Perl, in particular in cases where the result
374        is a non-match for a non-anchored pattern. For example, if
375        /b(*:m)f|a(*:n)w/ is matched against "abc", the non-match returns the name
376        "m", where previously it did not return a name. A side effect of this
377        change is that for partial matches, the last encountered mark name is
378        returned, as for non matches. A number of tests that were previously not
379        Perl-compatible have been moved into the Perl-compatible test files. The
380        refactoring has had the pleasing side effect of removing one argument from
381        the match() function, thus reducing its stack requirements.
382    
383    19. If the /S+ option was used in pcretest to study a pattern using JIT,
384        subsequent uses of /S (without +) incorrectly behaved like /S+.
385    
386    21. Retrieve executable code size support for the JIT compiler and fixing
387        some warnings.
388    
389    22. A caseless match of a UTF-8 character whose other case uses fewer bytes did
390        not work when the shorter character appeared right at the end of the
391        subject string.
392    
393    23. Added some (int) casts to non-JIT modules to reduce warnings on 64-bit
394        systems.
395    
396    24. Added PCRE_INFO_JITSIZE to pass on the value from (21) above, and also
397        output it when the /M option is used in pcretest.
398    
399    25. The CheckMan script was not being included in the distribution. Also, added
400        an explicit "perl" to run Perl scripts from the PrepareRelease script
401        because this is reportedly needed in Windows.
402    
403    26. If study data was being save in a file and studying had not found a set of
404        "starts with" bytes for the pattern, the data written to the file (though
405        never used) was taken from uninitialized memory and so caused valgrind to
406        complain.
407    
408    27. Updated RunTest.bat as provided by Sheri Pierce.
409    
410    28. Fixed a possible uninitialized memory bug in pcre_jit_compile.c.
411    
412    29. Computation of memory usage for the table of capturing group names was
413        giving an unnecessarily large value.
414    
415    
416    Version 8.20 21-Oct-2011
417    ------------------------
418    
419    1.  Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
420        a POSIX class. After further experiments with Perl, which convinced me that
421        Perl has bugs and confusions, a closing square bracket is no longer allowed
422        in a POSIX name. This bug also affected patterns with classes that started
423        with full stops.
424    
425    2.  If a pattern such as /(a)b|ac/ is matched against "ac", there is no
426        captured substring, but while checking the failing first alternative,
427        substring 1 is temporarily captured. If the output vector supplied to
428        pcre_exec() was not big enough for this capture, the yield of the function
429        was still zero ("insufficient space for captured substrings"). This cannot
430        be totally fixed without adding another stack variable, which seems a lot
431        of expense for a edge case. However, I have improved the situation in cases
432        such as /(a)(b)x|abc/ matched against "abc", where the return code
433        indicates that fewer than the maximum number of slots in the ovector have
434        been set.
435    
436    3.  Related to (2) above: when there are more back references in a pattern than
437        slots in the output vector, pcre_exec() uses temporary memory during
438        matching, and copies in the captures as far as possible afterwards. It was
439        using the entire output vector, but this conflicts with the specification
440        that only 2/3 is used for passing back captured substrings. Now it uses
441        only the first 2/3, for compatibility. This is, of course, another edge
442        case.
443    
444    4.  Zoltan Herczeg's just-in-time compiler support has been integrated into the
445        main code base, and can be used by building with --enable-jit. When this is
446        done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
447        runtime --no-jit option is given.
448    
449    5.  When the number of matches in a pcre_dfa_exec() run exactly filled the
450        ovector, the return from the function was zero, implying that there were
451        other matches that did not fit. The correct "exactly full" value is now
452        returned.
453    
454    6.  If a subpattern that was called recursively or as a subroutine contained
455        (*PRUNE) or any other control that caused it to give a non-standard return,
456        invalid errors such as "Error -26 (nested recursion at the same subject
457        position)" or even infinite loops could occur.
458    
459    7.  If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
460        computing the minimum length on reaching *ACCEPT, and so ended up with the
461        wrong value of 1 rather than 0. Further investigation indicates that
462        computing a minimum subject length in the presence of *ACCEPT is difficult
463        (think back references, subroutine calls), and so I have changed the code
464        so that no minimum is registered for a pattern that contains *ACCEPT.
465    
466    8.  If (*THEN) was present in the first (true) branch of a conditional group,
467        it was not handled as intended. [But see 16 below.]
468    
469    9.  Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
470        Sheri Pierce.
471    
472    10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
473        the first byte in a match must be "a".
474    
475    11. Change 17 for 8.13 increased the recursion depth for patterns like
476        /a(?:.)*?a/ drastically. I've improved things by remembering whether a
477        pattern contains any instances of (*THEN). If it does not, the old
478        optimizations are restored. It would be nice to do this on a per-group
479        basis, but at the moment that is not feasible.
480    
481    12. In some environments, the output of pcretest -C is CRLF terminated. This
482        broke RunTest's code that checks for the link size. A single white space
483        character after the value is now allowed for.
484    
485    13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
486        For "fr", it uses the Windows-specific input and output files.
487    
488    14. If (*THEN) appeared in a group that was called recursively or as a
489        subroutine, it did not work as intended. [But see next item.]
490    
491    15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
492        pattern fragments (but not containing any | characters). If A and B are
493        matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
494        was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
495        D. In other words, Perl considers parentheses that do not contain any |
496        characters to be part of a surrounding alternative, whereas PCRE was
497        treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
498        differently. PCRE now behaves in the same way as Perl, except in the case
499        of subroutine/recursion calls such as (?1) which have in any case always
500        been different (but PCRE had them first :-).
501    
502    16. Related to 15 above: Perl does not treat the | in a conditional group as
503        creating alternatives. Such a group is treated in the same way as an
504        ordinary group without any | characters when processing (*THEN). PCRE has
505        been changed to match Perl's behaviour.
506    
507    17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
508        RunGrepTest script failed.
509    
510    18. Change 22 for version 13 caused atomic groups to use more stack. This is
511        inevitable for groups that contain captures, but it can lead to a lot of
512        stack use in large patterns. The old behaviour has been restored for atomic
513        groups that do not contain any capturing parentheses.
514    
515    19. If the PCRE_NO_START_OPTIMIZE option was set for pcre_compile(), it did not
516        suppress the check for a minimum subject length at run time. (If it was
517        given to pcre_exec() or pcre_dfa_exec() it did work.)
518    
519    20. Fixed an ASCII-dependent infelicity in pcretest that would have made it
520        fail to work when decoding hex characters in data strings in EBCDIC
521        environments.
522    
523    21. It appears that in at least one Mac OS environment, the isxdigit() function
524        is implemented as a macro that evaluates to its argument more than once,
525        contravening the C 90 Standard (I haven't checked a later standard). There
526        was an instance in pcretest which caused it to go wrong when processing
527        \x{...} escapes in subject strings. The has been rewritten to avoid using
528        things like p++ in the argument of isxdigit().
529    
530    
531    Version 8.13 16-Aug-2011
532    ------------------------
533    
534    1.  The Unicode data tables have been updated to Unicode 6.0.0.
535    
536    2.  Two minor typos in pcre_internal.h have been fixed.
537    
538    3.  Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
539        pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
540        in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
541    
542    4.  There were a number of related bugs in the code for matching backrefences
543        caselessly in UTF-8 mode when codes for the characters concerned were
544        different numbers of bytes. For example, U+023A and U+2C65 are an upper
545        and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
546        (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
547        code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
548        2-byte code at the end of the subject (it thought there wasn't enough data
549        left).
550    
551    5.  Comprehensive information about what went wrong is now returned by
552        pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
553        as the output vector has at least 2 elements. The offset of the start of
554        the failing character and a reason code are placed in the vector.
555    
556    6.  When the UTF-8 string check fails for pcre_compile(), the offset that is
557        now returned is for the first byte of the failing character, instead of the
558        last byte inspected. This is an incompatible change, but I hope it is small
559        enough not to be a problem. It makes the returned offset consistent with
560        pcre_exec() and pcre_dfa_exec().
561    
562    7.  pcretest now gives a text phrase as well as the error number when
563        pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
564        failure, the offset and reason code are output.
565    
566    8.  When \R was used with a maximizing quantifier it failed to skip backwards
567        over a \r\n pair if the subsequent match failed. Instead, it just skipped
568        back over a single character (\n). This seems wrong (because it treated the
569        two characters as a single entity when going forwards), conflicts with the
570        documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
571        behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
572        has been changed.
573    
574    9.  Some internal refactoring has changed the processing so that the handling
575        of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
576        time (the PCRE_DOTALL option was changed this way some time ago: version
577        7.7 change 16). This has made it possible to abolish the OP_OPT op code,
578        which was always a bit of a fudge. It also means that there is one less
579        argument for the match() function, which reduces its stack requirements
580        slightly. This change also fixes an incompatibility with Perl: the pattern
581        (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
582    
583    10. More internal refactoring has drastically reduced the number of recursive
584        calls to match() for possessively repeated groups such as (abc)++ when
585        using pcre_exec().
586    
587    11. While implementing 10, a number of bugs in the handling of groups were
588        discovered and fixed:
589    
590        (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
591        (a|)*(?1) gave a compile-time internal error.
592        ((a|)+)+  did not notice that the outer group could match an empty string.
593        (^a|^)+   was not marked as anchored.
594        (.*a|.*)+ was not marked as matching at start or after a newline.
595    
596    12. Yet more internal refactoring has removed another argument from the match()
597        function. Special calls to this function are now indicated by setting a
598        value in a variable in the "match data" data block.
599    
600    13. Be more explicit in pcre_study() instead of relying on "default" for
601        opcodes that mean there is no starting character; this means that when new
602        ones are added and accidentally left out of pcre_study(), testing should
603        pick them up.
604    
605    14. The -s option of pcretest has been documented for ages as being an old
606        synonym of -m (show memory usage). I have changed it to mean "force study
607        for every regex", that is, assume /S for every regex. This is similar to -i
608        and -d etc. It's slightly incompatible, but I'm hoping nobody is still
609        using it. It makes it easier to run collections of tests with and without
610        study enabled, and thereby test pcre_study() more easily. All the standard
611        tests are now run with and without -s (but some patterns can be marked as
612        "never study" - see 20 below).
613    
614    15. When (*ACCEPT) was used in a subpattern that was called recursively, the
615        restoration of the capturing data to the outer values was not happening
616        correctly.
617    
618    16. If a recursively called subpattern ended with (*ACCEPT) and matched an
619        empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
620        pattern had matched an empty string, and so incorrectly returned a no
621        match.
622    
623    17. There was optimizing code for the last branch of non-capturing parentheses,
624        and also for the obeyed branch of a conditional subexpression, which used
625        tail recursion to cut down on stack usage. Unfortunately, now that there is
626        the possibility of (*THEN) occurring in these branches, tail recursion is
627        no longer possible because the return has to be checked for (*THEN). These
628        two optimizations have therefore been removed. [But see 8.20/11 above.]
629    
630    18. If a pattern containing \R was studied, it was assumed that \R always
631        matched two bytes, thus causing the minimum subject length to be
632        incorrectly computed because \R can also match just one byte.
633    
634    19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
635        was incorrectly computed.
636    
637    20. If /S is present twice on a test pattern in pcretest input, it now
638        *disables* studying, thereby overriding the use of -s on the command line
639        (see 14 above). This is necessary for one or two tests to keep the output
640        identical in both cases.
641    
642    21. When (*ACCEPT) was used in an assertion that matched an empty string and
643        PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
644    
645    22. When an atomic group that contained a capturing parenthesis was
646        successfully matched, but the branch in which it appeared failed, the
647        capturing was not being forgotten if a higher numbered group was later
648        captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
649        group 1 to "a", when in fact it should be unset. This applied to multi-
650        branched capturing and non-capturing groups, repeated or not, and also to
651        positive assertions (capturing in negative assertions does not happen
652        in PCRE) and also to nested atomic groups.
653    
654    23. Add the ++ qualifier feature to pcretest, to show the remainder of the
655        subject after a captured substring, to make it easier to tell which of a
656        number of identical substrings has been captured.
657    
658    24. The way atomic groups are processed by pcre_exec() has been changed so that
659        if they are repeated, backtracking one repetition now resets captured
660        values correctly. For example, if ((?>(a+)b)+aabab) is matched against
661        "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
662        "aaa". Previously, it would have been "a". As part of this code
663        refactoring, the way recursive calls are handled has also been changed.
664    
665    25. If an assertion condition captured any substrings, they were not passed
666        back unless some other capturing happened later. For example, if
667        (?(?=(a))a) was matched against "a", no capturing was returned.
668    
669    26. When studying a pattern that contained subroutine calls or assertions,
670        the code for finding the minimum length of a possible match was handling
671        direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
672        group 1 called group 2 while simultaneously a separate group 2 called group
673        1). A stack overflow occurred in this case. I have fixed this by limiting
674        the recursion depth to 10.
675    
676    27. Updated RunTest.bat in the distribution to the version supplied by Tom
677        Fortmann. This supports explicit test numbers on the command line, and has
678        argument validation and error reporting.
679    
680    28. An instance of \X with an unlimited repeat could fail if at any point the
681        first character it looked at was a mark character.
682    
683    29. Some minor code refactoring concerning Unicode properties and scripts
684        should reduce the stack requirement of match() slightly.
685    
686    30. Added the '=' option to pcretest to check the setting of unused capturing
687        slots at the end of the pattern, which are documented as being -1, but are
688        not included in the return count.
689    
690    31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
691        compiled something random. Now it gives a compile-time error (as does
692        Perl).
693    
694    32. A *MARK encountered during the processing of a positive assertion is now
695        recorded and passed back (compatible with Perl).
696    
697    33. If --only-matching or --colour was set on a pcregrep call whose pattern
698        had alternative anchored branches, the search for a second match in a line
699        was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
700        matched the line "0102" twice. The same bug affected patterns that started
701        with a backwards assertion. For example /\b01|\b02/ also matched "0102"
702        twice.
703    
704    34. Previously, PCRE did not allow quantification of assertions. However, Perl
705        does, and because of capturing effects, quantifying parenthesized
706        assertions may at times be useful. Quantifiers are now allowed for
707        parenthesized assertions.
708    
709    35. A minor code tidy in pcre_compile() when checking options for \R usage.
710    
711    36. \g was being checked for fancy things in a character class, when it should
712        just be a literal "g".
713    
714    37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
715        appearance of a nested POSIX class supersedes an apparent external class.
716        For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
717        unescaped square brackets may also appear as part of class names. For
718        example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
719        more like Perl. (But see 8.20/1 above.)
720    
721    38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
722        was because it thought it was \N{name}, which is not supported).
723    
724    39. Add minix to OS list not supporting the -S option in pcretest.
725    
726    40. PCRE tries to detect cases of infinite recursion at compile time, but it
727        cannot analyze patterns in sufficient detail to catch mutual recursions
728        such as ((?1))((?2)). There is now a runtime test that gives an error if a
729        subgroup is called recursively as a subpattern for a second time at the
730        same position in the subject string. In previous releases this might have
731        been caught by the recursion limit, or it might have run out of stack.
732    
733    41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
734        happen only once. PCRE was, however incorrectly giving a compile time error
735        "recursive call could loop indefinitely" because it cannot analyze the
736        pattern in sufficient detail. The compile time test no longer happens when
737        PCRE is compiling a conditional subpattern, but actual runaway loops are
738        now caught at runtime (see 40 above).
739    
740    42. It seems that Perl allows any characters other than a closing parenthesis
741        to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
742        has been changed to be the same.
743    
744    43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
745        as not to get warnings when autogen.sh is called. Also changed
746        AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
747    
748    44. To help people who use pcregrep to scan files containing exceedingly long
749        lines, the following changes have been made:
750    
751        (a) The default value of the buffer size parameter has been increased from
752            8K to 20K. (The actual buffer used is three times this size.)
753    
754        (b) The default can be changed by ./configure --with-pcregrep-bufsize when
755            PCRE is built.
756    
757        (c) A --buffer-size=n option has been added to pcregrep, to allow the size
758            to be set at run time.
759    
760        (d) Numerical values in pcregrep options can be followed by K or M, for
761            example --buffer-size=50K.
762    
763        (e) If a line being scanned overflows pcregrep's buffer, an error is now
764            given and the return code is set to 2.
765    
766    45. Add a pointer to the latest mark to the callout data block.
767    
768    46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
769        partial match of an empty string instead of no match. This was specific to
770        the use of ".".
771    
772    47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
773        complete match instead of a partial match. This bug was dependent on both
774        the PCRE_UTF8 and PCRE_DOTALL options being set.
775    
776    48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
777        starting byte set, because \b was not being ignored.
778    
779    
780    Version 8.12 15-Jan-2011
781    ------------------------
782    
783    1.  Fixed some typos in the markup of the man pages, and wrote a script that
784        checks for such things as part of the documentation building process.
785    
786    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
787        --match-limit and --recursion-limit options (added for 8.11). In
788        particular, this made one of the standard tests fail. (The integer value
789        went into the wrong half of a long int.)
790    
791    3.  If the --colour option was given to pcregrep with -v (invert match), it
792        did strange things, either producing crazy output, or crashing. It should,
793        of course, ignore a request for colour when reporting lines that do not
794        match.
795    
796    4.  Another pcregrep bug caused similar problems if --colour was specified with
797        -M (multiline) and the pattern match finished with a line ending.
798    
799    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
800        matched in multiline mode, the following line was shown as part of the
801        match. This seems wrong, so I have changed it.
802    
803    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
804        the check for further matches in the same line (so they could be coloured)
805        to overrun the end of the current line. If another match was found, it was
806        incorrectly shown (and then shown again when found in the next line).
807    
808    7.  If pcregrep was compiled under Windows, there was a reference to the
809        function pcregrep_exit() before it was defined. I am assuming this was
810        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
811        reported by a user. I've moved the definition above the reference.
812    
813    
814    Version 8.11 10-Dec-2010
815    ------------------------
816    
817    1.  (*THEN) was not working properly if there were untried alternatives prior
818        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
819        backtracked to try for "b" instead of moving to the next alternative branch
820        at the same level (in this case, to look for "c"). The Perl documentation
821        is clear that when (*THEN) is backtracked onto, it goes to the "next
822        alternative in the innermost enclosing group".
823    
824    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
825        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
826        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
827        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
828        (*THEN).
829    
830    3.  If \s appeared in a character class, it removed the VT character from
831        the class, even if it had been included by some previous item, for example
832        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
833        of \s, but is part of the POSIX "space" class.)
834    
835    4.  A partial match never returns an empty string (because you can always
836        match an empty string at the end of the subject); however the checking for
837        an empty string was starting at the "start of match" point. This has been
838        changed to the "earliest inspected character" point, because the returned
839        data for a partial match starts at this character. This means that, for
840        example, /(?<=abc)def/ gives a partial match for the subject "abc"
841        (previously it gave "no match").
842    
843    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
844        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
845        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
846        has an implication that the given string is incomplete (because a partial
847        match is preferred over a full match). For this reason, these items now
848        give a partial match in this situation. [Aside: previously, the one case
849        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
850        match rather than a full match, which was wrong by the old rules, but is
851        now correct.]
852    
853    6.  There was a bug in the handling of #-introduced comments, recognized when
854        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
855        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
856        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
857        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
858        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
859        places in pcre_compile().
860    
861    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
862        comments when looking ahead for named forward references to subpatterns,
863        the only newline sequence it recognized was NL. It now handles newlines
864        according to the set newline convention.
865    
866    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
867        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
868        cater for a lack of strerror(). These oversights have been fixed.
869    
870    9.  Added --match-limit and --recursion-limit to pcregrep.
871    
872    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
873    
874    11. When the -o option was used, pcregrep was setting a return code of 1, even
875        when matches were found, and --line-buffered was not being honoured.
876    
877    12. Added an optional parentheses number to the -o and --only-matching options
878        of pcregrep.
879    
880    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
881        can match an empty string. The code to do it in pcretest and pcredemo
882        needed fixing:
883    
884        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
885            only one byte after an empty string match just before CRLF (this case
886            just got forgotten; "any" and "anycrlf" were OK).
887    
888        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
889            mode when an empty string match preceded an ASCII character followed by
890            a non-ASCII character. (The code for advancing by one character rather
891            than one byte was nonsense.)
892    
893        (c) The pcredemo.c sample program did not have any code at all to handle
894            the cases when CRLF is a valid newline sequence.
895    
896    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
897        as a starting offset was within the subject string. There is now a new
898        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
899        negative or greater than the length of the string. In order to test this,
900        pcretest is extended to allow the setting of negative starting offsets.
901    
902    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
903        starting offset points to the beginning of a UTF-8 character was
904        unnecessarily clumsy. I tidied it up.
905    
906    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
907        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
908    
909    17. Nobody had reported that the --include_dir option, which was added in
910        release 7.7 should have been called --include-dir (hyphen, not underscore)
911        for compatibility with GNU grep. I have changed it to --include-dir, but
912        left --include_dir as an undocumented synonym, and the same for
913        --exclude-dir, though that is not available in GNU grep, at least as of
914        release 2.5.4.
915    
916    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
917        characters from a string of bytes) have been redefined so as not to use
918        loops, in order to improve performance in some environments. At the same
919        time, I abstracted some of the common code into auxiliary macros to save
920        repetition (this should not affect the compiled code).
921    
922    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
923        compile-time error is now given if \c is not followed by an ASCII
924        character, that is, a byte less than 128. (In EBCDIC mode, the code is
925        different, and any byte value is allowed.)
926    
927    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
928        START_OPTIMIZE option, which is now allowed at compile time - but just
929        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
930        to pcregrep and other applications that have no direct access to PCRE
931        options. The new /Y option in pcretest sets this option when calling
932        pcre_compile().
933    
934    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
935        back references. Groups containing recursive back references were forced to
936        be atomic by that change, but in the case of named groups, the amount of
937        memory required was incorrectly computed, leading to "Failed: internal
938        error: code overflow". This has been fixed.
939    
940    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
941        pcretest.c, to avoid build problems in some Borland environments.
942    
943    
944    Version 8.10 25-Jun-2010
945    ------------------------
946    
947    1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
948        THEN.
949    
950    2.  (*ACCEPT) was not working when inside an atomic group.
951    
952    3.  Inside a character class, \B is treated as a literal by default, but
953        faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
954        causes the error). The code is unchanged, but I tidied the documentation.
955    
956    4.  Inside a character class, PCRE always treated \R and \X as literals,
957        whereas Perl faults them if its -w option is set. I have changed PCRE so
958        that it faults them when PCRE_EXTRA is set.
959    
960    5.  Added support for \N, which always matches any character other than
961        newline. (It is the same as "." when PCRE_DOTALL is not set.)
962    
963    6.  When compiling pcregrep with newer versions of gcc which may have
964        FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
965        declared with attribute warn_unused_result" were given. Just casting the
966        result to (void) does not stop the warnings; a more elaborate fudge is
967        needed. I've used a macro to implement this.
968    
969    7.  Minor change to pcretest.c to avoid a compiler warning.
970    
971    8.  Added four artifical Unicode properties to help with an option to make
972        \s etc use properties (see next item). The new properties are: Xan
973        (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
974    
975    9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
976        use Unicode properties. (*UCP) at the start of a pattern can be used to set
977        this option. Modified pcretest to add /W to test this facility. Added
978        REG_UCP to make it available via the POSIX interface.
979    
980    10. Added --line-buffered to pcregrep.
981    
982    11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
983        studied, and the match started with a letter with a code point greater than
984        127 whose first byte was different to the first byte of the other case of
985        the letter, the other case of this starting letter was not recognized
986        (#976).
987    
988    12. If a pattern that was studied started with a repeated Unicode property
989        test, for example, \p{Nd}+, there was the theoretical possibility of
990        setting up an incorrect bitmap of starting bytes, but fortunately it could
991        not have actually happened in practice until change 8 above was made (it
992        added property types that matched character-matching opcodes).
993    
994    13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
995        possible starting bytes for non-anchored patterns.
996    
997    14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
998        \R, and also a number of cases that involve Unicode properties, both
999        explicit and implicit when PCRE_UCP is set.
1000    
1001    15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
1002        input, it could crash or give wrong results if characters with values
1003        greater than 0xc0 were present in the subject string. (Detail: it assumed
1004        UTF-8 input when processing these items.)
1005    
1006    16. Added a lot of (int) casts to avoid compiler warnings in systems where
1007        size_t is 64-bit (#991).
1008    
1009    17. Added a check for running out of memory when PCRE is compiled with
1010        --disable-stack-for-recursion (#990).
1011    
1012    18. If the last data line in a file for pcretest does not have a newline on
1013        the end, a newline was missing in the output.
1014    
1015    19. The default pcre_chartables.c file recognizes only ASCII characters (values
1016        less than 128) in its various bitmaps. However, there is a facility for
1017        generating tables according to the current locale when PCRE is compiled. It
1018        turns out that in some environments, 0x85 and 0xa0, which are Unicode space
1019        characters, are recognized by isspace() and therefore were getting set in
1020        these tables, and indeed these tables seem to approximate to ISO 8859. This
1021        caused a problem in UTF-8 mode when pcre_study() was used to create a list
1022        of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
1023        which of course cannot start UTF-8 characters. I have changed the code so
1024        that only real ASCII characters (less than 128) and the correct starting
1025        bytes for UTF-8 encodings are set for characters greater than 127 when in
1026        UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
1027        altogether.)
1028    
1029    20. Added the /T option to pcretest so as to be able to run tests with non-
1030        standard character tables, thus making it possible to include the tests
1031        used for 19 above in the standard set of tests.
1032    
1033    21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
1034        reference to a subpattern the other side of a comment that contains an
1035        opening parenthesis caused either an internal compiling error, or a
1036        reference to the wrong subpattern.
1037    
1038    
1039    Version 8.02 19-Mar-2010
1040    ------------------------
1041    
1042    1.  The Unicode data tables have been updated to Unicode 5.2.0.
1043    
1044    2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
1045        configured.
1046    
1047    3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
1048        original author of that file, following a query about its status.
1049    
1050    4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
1051        inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
1052    
1053    5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
1054        quantifier applied to a forward-referencing subroutine call, could compile
1055        incorrect code or give the error "internal error: previously-checked
1056        referenced subpattern not found".
1057    
1058    6.  Both MS Visual Studio and Symbian OS have problems with initializing
1059        variables to point to external functions. For these systems, therefore,
1060        pcre_malloc etc. are now initialized to local functions that call the
1061        relevant global functions.
1062    
1063    7.  There were two entries missing in the vectors called coptable and poptable
1064        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
1065        I've fixed the data, and added a kludgy way of testing at compile time that
1066        the lengths are correct (equal to the number of opcodes).
1067    
1068    8.  Following on from 7, I added a similar kludge to check the length of the
1069        eint vector in pcreposix.c.
1070    
1071    9.  Error texts for pcre_compile() are held as one long string to avoid too
1072        much relocation at load time. To find a text, the string is searched,
1073        counting zeros. There was no check for running off the end of the string,
1074        which could happen if a new error number was added without updating the
1075        string.
1076    
1077    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
1078    
1079    11. \K was not working if it appeared in an atomic group or in a group that
1080        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
1081        \K is "not well defined" if used in an assertion. PCRE now accepts it if
1082        the assertion is positive, but not if it is negative.
1083    
1084    12. Change 11 fortuitously reduced the size of the stack frame used in the
1085        "match()" function of pcre_exec.c by one pointer. Forthcoming
1086        implementation of support for (*MARK) will need an extra pointer on the
1087        stack; I have reserved it now, so that the stack frame size does not
1088        decrease.
1089    
1090    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
1091        item in branch that calls a recursion is a subroutine call - as in the
1092        second branch in the above example - was incorrectly given the compile-
1093        time error "recursive call could loop indefinitely" because pcre_compile()
1094        was not correctly checking the subroutine for matching a non-empty string.
1095    
1096    14. The checks for overrunning compiling workspace could trigger after an
1097        overrun had occurred. This is a "should never occur" error, but it can be
1098        triggered by pathological patterns such as hundreds of nested parentheses.
1099        The checks now trigger 100 bytes before the end of the workspace.
1100    
1101    15. Fix typo in configure.ac: "srtoq" should be "strtoq".
1102    
1103    
1104    Version 8.01 19-Jan-2010
1105    ------------------------
1106    
1107    1.  If a pattern contained a conditional subpattern with only one branch (in
1108        particular, this includes all (*DEFINE) patterns), a call to pcre_study()
1109        computed the wrong minimum data length (which is of course zero for such
1110        subpatterns). This could cause incorrect "no match" results.
1111    
1112    2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
1113        the pattern is reset in the first branch, pcre_compile() failed with
1114        "internal error: code overflow at offset...". This happened only when
1115        the reset was to the original external option setting. (An optimization
1116        abstracts leading options settings into an external setting, which was the
1117        cause of this.)
1118    
1119    3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
1120        of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
1121        assertion pattern did not match (meaning that the assertion was true), it
1122        was incorrectly treated as false if the SKIP had been reached during the
1123        matching. This also applied to assertions used as conditions.
1124    
1125    4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
1126        assertion subpattern, including such a pattern used as a condition,
1127        unpredictable results occurred, instead of the error return
1128        PCRE_ERROR_DFA_UITEM.
1129    
1130    5.  The C++ GlobalReplace function was not working like Perl for the special
1131        situation when an empty string is matched. It now does the fancy magic
1132        stuff that is necessary.
1133    
1134    6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
1135        removed. (These were left over from very, very early versions of PCRE.)
1136    
1137    7.  Some cosmetic changes to the code to make life easier when compiling it
1138        as part of something else:
1139    
1140        (a) Change DEBUG to PCRE_DEBUG.
1141    
1142        (b) In pcre_compile(), rename the member of the "branch_chain" structure
1143            called "current" as "current_branch", to prevent a collision with the
1144            Linux macro when compiled as a kernel module.
1145    
1146        (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
1147            prevent a collision with the Linux macro when compiled as a kernel
1148            module.
1149    
1150    8.  In pcre_compile() there are some checks for integer overflows that used to
1151        cast potentially large values to (double). This has been changed to that
1152        when building, a check for int64_t is made, and if it is found, it is used
1153        instead, thus avoiding the use of floating point arithmetic. (There is no
1154        other use of FP in PCRE.) If int64_t is not found, the fallback is to
1155        double.
1156    
1157    9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
1158        2005 (difference between two addresses compared to an unsigned value).
1159    
1160    10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
1161        custom one, because of the following reported problem in Windows:
1162    
1163          - libbz2 uses the Pascal calling convention (WINAPI) for the functions
1164              under Win32.
1165          - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
1166              therefore missing the function definition.
1167          - The compiler thus generates a "C" signature for the test function.
1168          - The linker fails to find the "C" function.
1169          - PCRE fails to configure if asked to do so against libbz2.
1170    
1171    11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
1172        messages were output:
1173    
1174          Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
1175          rerunning libtoolize, to keep the correct libtool macros in-tree.
1176          Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
1177    
1178        I have done both of these things.
1179    
1180    12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
1181        most of the time, it *can* run out if it is given a pattern that contains a
1182        runaway infinite recursion. I updated the discussion in the pcrestack man
1183        page.
1184    
1185    13. Now that we have gone to the x.xx style of version numbers, the minor
1186        version may start with zero. Using 08 or 09 is a bad idea because users
1187        might check the value of PCRE_MINOR in their code, and 08 or 09 may be
1188        interpreted as invalid octal numbers. I've updated the previous comment in
1189        configure.ac, and also added a check that gives an error if 08 or 09 are
1190        used.
1191    
1192    14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
1193        causing partial matching to fail when the end of the subject matched \W
1194        in a UTF-8 pattern where \W was quantified with a minimum of 3.
1195    
1196    15. There were some discrepancies between the declarations in pcre_internal.h
1197        of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
1198        their definitions. The declarations used "const uschar *" and the
1199        definitions used USPTR. Even though USPTR is normally defined as "const
1200        unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
1201        reported that: "This difference in casting confuses some C++ compilers, for
1202        example, SunCC recognizes above declarations as different functions and
1203        generates broken code for hbpcre." I have changed the declarations to use
1204        USPTR.
1205    
1206    16. GNU libtool is named differently on some systems. The autogen.sh script now
1207        tries several variants such as glibtoolize (MacOSX) and libtoolize1x
1208        (FreeBSD).
1209    
1210    17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
1211        (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
1212        comment: "Figure out how to create a longlong from a string: strtoll and
1213        equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
1214        instance, but it only takes 2 args instead of 3!"
1215    
1216    18. A subtle bug concerned with back references has been fixed by a change of
1217        specification, with a corresponding code fix. A pattern such as
1218        ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
1219        refers, was giving matches when it shouldn't. For example, xa=xaaa would
1220        match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
1221        same bug. Such groups have to be quantified to be useful, or contained
1222        inside another quantified group. (If there's no repetition, the reference
1223        can never match.) The problem arises because, having left the group and
1224        moved on to the rest of the pattern, a later failure that backtracks into
1225        the group uses the captured value from the final iteration of the group
1226        rather than the correct earlier one. I have fixed this in PCRE by forcing
1227        any group that contains a reference to itself to be an atomic group; that
1228        is, there cannot be any backtracking into it once it has completed. This is
1229        similar to recursive and subroutine calls.
1230    
1231    
1232    Version 8.00 19-Oct-09
1233    ----------------------
1234    
1235    1.  The table for translating pcre_compile() error codes into POSIX error codes
1236        was out-of-date, and there was no check on the pcre_compile() error code
1237        being within the table. This could lead to an OK return being given in
1238        error.
1239    
1240    2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
1241        "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
1242        in a Windows environment.
1243    
1244    3.  The pcregrep --count option prints the count for each file even when it is
1245        zero, as does GNU grep. However, pcregrep was also printing all files when
1246        --files-with-matches was added. Now, when both options are given, it prints
1247        counts only for those files that have at least one match. (GNU grep just
1248        prints the file name in this circumstance, but including the count seems
1249        more useful - otherwise, why use --count?) Also ensured that the
1250        combination -clh just lists non-zero counts, with no names.
1251    
1252    4.  The long form of the pcregrep -F option was incorrectly implemented as
1253        --fixed_strings instead of --fixed-strings. This is an incompatible change,
1254        but it seems right to fix it, and I didn't think it was worth preserving
1255        the old behaviour.
1256    
1257    5.  The command line items --regex=pattern and --regexp=pattern were not
1258        recognized by pcregrep, which required --regex pattern or --regexp pattern
1259        (with a space rather than an '='). The man page documented the '=' forms,
1260        which are compatible with GNU grep; these now work.
1261    
1262    6.  No libpcreposix.pc file was created for pkg-config; there was just
1263        libpcre.pc and libpcrecpp.pc. The omission has been rectified.
1264    
1265    7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
1266        when UCP support is not needed, by modifying the Python script that
1267        generates it from Unicode data files. This should not matter if the module
1268        is correctly used as a library, but I received one complaint about 50K of
1269        unwanted data. My guess is that the person linked everything into his
1270        program rather than using a library. Anyway, it does no harm.
1271    
1272    8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
1273        was a minimum greater than 1 for a wide character in a possessive
1274        repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
1275        which had an unlimited repeat of a nested, fixed maximum repeat of a wide
1276        character. Chaos in the form of incorrect output or a compiling loop could
1277        result.
1278    
1279    9.  The restrictions on what a pattern can contain when partial matching is
1280        requested for pcre_exec() have been removed. All patterns can now be
1281        partially matched by this function. In addition, if there are at least two
1282        slots in the offset vector, the offset of the earliest inspected character
1283        for the match and the offset of the end of the subject are set in them when
1284        PCRE_ERROR_PARTIAL is returned.
1285    
1286    10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
1287        synonymous with PCRE_PARTIAL, for backwards compatibility, and
1288        PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
1289        and may be more useful for multi-segment matching.
1290    
1291    11. Partial matching with pcre_exec() is now more intuitive. A partial match
1292        used to be given if ever the end of the subject was reached; now it is
1293        given only if matching could not proceed because another character was
1294        needed. This makes a difference in some odd cases such as Z(*FAIL) with the
1295        string "Z", which now yields "no match" instead of "partial match". In the
1296        case of pcre_dfa_exec(), "no match" is given if every matching path for the
1297        final character ended with (*FAIL).
1298    
1299    12. Restarting a match using pcre_dfa_exec() after a partial match did not work
1300        if the pattern had a "must contain" character that was already found in the
1301        earlier partial match, unless partial matching was again requested. For
1302        example, with the pattern /dog.(body)?/, the "must contain" character is
1303        "g". If the first part-match was for the string "dog", restarting with
1304        "sbody" failed. This bug has been fixed.
1305    
1306    13. The string returned by pcre_dfa_exec() after a partial match has been
1307        changed so that it starts at the first inspected character rather than the
1308        first character of the match. This makes a difference only if the pattern
1309        starts with a lookbehind assertion or \b or \B (\K is not supported by
1310        pcre_dfa_exec()). It's an incompatible change, but it makes the two
1311        matching functions compatible, and I think it's the right thing to do.
1312    
1313    14. Added a pcredemo man page, created automatically from the pcredemo.c file,
1314        so that the demonstration program is easily available in environments where
1315        PCRE has not been installed from source.
1316    
1317    15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
1318        libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
1319        library.
1320    
1321    16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
1322        It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
1323        is not the first non-POSIX option to be added. Clearly some people find
1324        these options useful.
1325    
1326    17. If a caller to the POSIX matching function regexec() passes a non-zero
1327        value for nmatch with a NULL value for pmatch, the value of
1328        nmatch is forced to zero.
1329    
1330    18. RunGrepTest did not have a test for the availability of the -u option of
1331        the diff command, as RunTest does. It now checks in the same way as
1332        RunTest, and also checks for the -b option.
1333    
1334    19. If an odd number of negated classes containing just a single character
1335        interposed, within parentheses, between a forward reference to a named
1336        subpattern and the definition of the subpattern, compilation crashed with
1337        an internal error, complaining that it could not find the referenced
1338        subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
1339        [The bug was that it was starting one character too far in when skipping
1340        over the character class, thus treating the ] as data rather than
1341        terminating the class. This meant it could skip too much.]
1342    
1343    20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
1344        /g option in pcretest when the pattern contains \K, which makes it possible
1345        to have an empty string match not at the start, even when the pattern is
1346        anchored. Updated pcretest and pcredemo to use this option.
1347    
1348    21. If the maximum number of capturing subpatterns in a recursion was greater
1349        than the maximum at the outer level, the higher number was returned, but
1350        with unset values at the outer level. The correct (outer level) value is
1351        now given.
1352    
1353    22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
1354        PCRE did not set those parentheses (unlike Perl). I have now found a way to
1355        make it do so. The string so far is captured, making this feature
1356        compatible with Perl.
1357    
1358    23. The tests have been re-organized, adding tests 11 and 12, to make it
1359        possible to check the Perl 5.10 features against Perl 5.10.
1360    
1361    24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
1362        pattern matches a fixed length string. PCRE did not allow this; now it
1363        does. Neither allows recursion.
1364    
1365    25. I finally figured out how to implement a request to provide the minimum
1366        length of subject string that was needed in order to match a given pattern.
1367        (It was back references and recursion that I had previously got hung up
1368        on.) This code has now been added to pcre_study(); it finds a lower bound
1369        to the length of subject needed. It is not necessarily the greatest lower
1370        bound, but using it to avoid searching strings that are too short does give
1371        some useful speed-ups. The value is available to calling programs via
1372        pcre_fullinfo().
1373    
1374    26. While implementing 25, I discovered to my embarrassment that pcretest had
1375        not been passing the result of pcre_study() to pcre_dfa_exec(), so the
1376        study optimizations had never been tested with that matching function.
1377        Oops. What is worse, even when it was passed study data, there was a bug in
1378        pcre_dfa_exec() that meant it never actually used it. Double oops. There
1379        were also very few tests of studied patterns with pcre_dfa_exec().
1380    
1381    27. If (?| is used to create subpatterns with duplicate numbers, they are now
1382        allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
1383        on the other side of the coin, they are no longer allowed to have different
1384        names, because these cannot be distinguished in PCRE, and this has caused
1385        confusion. (This is a difference from Perl.)
1386    
1387    28. When duplicate subpattern names are present (necessarily with different
1388        numbers, as required by 27 above), and a test is made by name in a
1389        conditional pattern, either for a subpattern having been matched, or for
1390        recursion in such a pattern, all the associated numbered subpatterns are
1391        tested, and the overall condition is true if the condition is true for any
1392        one of them. This is the way Perl works, and is also more like the way
1393        testing by number works.
1394    
1395    
1396    Version 7.9 11-Apr-09
1397    ---------------------
1398    
1399    1.  When building with support for bzlib/zlib (pcregrep) and/or readline
1400        (pcretest), all targets were linked against these libraries. This included
1401        libpcre, libpcreposix, and libpcrecpp, even though they do not use these
1402        libraries. This caused unwanted dependencies to be created. This problem
1403        has been fixed, and now only pcregrep is linked with bzlib/zlib and only
1404        pcretest is linked with readline.
1405    
1406    2.  The "typedef int BOOL" in pcre_internal.h that was included inside the
1407        "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
1408        moved outside it again, because FALSE and TRUE are already defined in AIX,
1409        but BOOL is not.
1410    
1411    3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
1412        PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
1413    
1414    4.  The pcregrep documentation said spaces were inserted as well as colons (or
1415        hyphens) following file names and line numbers when outputting matching
1416        lines. This is not true; no spaces are inserted. I have also clarified the
1417        wording for the --colour (or --color) option.
1418    
1419    5.  In pcregrep, when --colour was used with -o, the list of matching strings
1420        was not coloured; this is different to GNU grep, so I have changed it to be
1421        the same.
1422    
1423    6.  When --colo(u)r was used in pcregrep, only the first matching substring in
1424        each matching line was coloured. Now it goes on to look for further matches
1425        of any of the test patterns, which is the same behaviour as GNU grep.
1426    
1427    7.  A pattern that could match an empty string could cause pcregrep to loop; it
1428        doesn't make sense to accept an empty string match in pcregrep, so I have
1429        locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
1430        seems to be how GNU grep behaves.
1431    
1432    8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
1433        start or after a newline", because the conditional assertion was not being
1434        correctly handled. The rule now is that both the assertion and what follows
1435        in the first alternative must satisfy the test.
1436    
1437    9.  If auto-callout was enabled in a pattern with a conditional group whose
1438        condition was an assertion, PCRE could crash during matching, both with
1439        pcre_exec() and pcre_dfa_exec().
1440    
1441    10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
1442        used for matching.
1443    
1444    11. Unicode property support in character classes was not working for
1445        characters (bytes) greater than 127 when not in UTF-8 mode.
1446    
1447    12. Added the -M command line option to pcretest.
1448    
1449    14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
1450    
1451    15. Added the PCRE_NO_START_OPTIMIZE match-time option.
1452    
1453    16. Added comments and documentation about mis-use of no_arg in the C++
1454        wrapper.
1455    
1456    17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
1457        from Martin Jerabek that uses macro names for all relevant character and
1458        string constants.
1459    
1460    18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
1461        SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
1462        SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
1463        these, but not everybody uses configure.
1464    
1465    19. A conditional group that had only one branch was not being correctly
1466        recognized as an item that could match an empty string. This meant that an
1467        enclosing group might also not be so recognized, causing infinite looping
1468        (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
1469        with the subject "ab", where knowledge that the repeated group can match
1470        nothing is needed in order to break the loop.
1471    
1472    20. If a pattern that was compiled with callouts was matched using pcre_dfa_
1473        exec(), but without supplying a callout function, matching went wrong.
1474    
1475    21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
1476        leak if the size of the offset vector was greater than 30. When the vector
1477        is smaller, the saved offsets during recursion go onto a local stack
1478        vector, but for larger vectors malloc() is used. It was failing to free
1479        when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
1480        error, in fact).
1481    
1482    22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
1483        heapframe that is used only when UTF-8 support is enabled. This caused no
1484        problem, but was untidy.
1485    
1486    23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
1487        CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
1488        included within another project.
1489    
1490    24. Steven Van Ingelgem's patches to add more options to the CMake support,
1491        slightly modified by me:
1492    
1493          (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
1494              not building pcregrep.
1495    
1496          (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
1497              if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
1498    
1499    25. Forward references, both numeric and by name, in patterns that made use of
1500        duplicate group numbers, could behave incorrectly or give incorrect errors,
1501        because when scanning forward to find the reference group, PCRE was not
1502        taking into account the duplicate group numbers. A pattern such as
1503        ^X(?3)(a)(?|(b)|(q))(Y) is an example.
1504    
1505    26. Changed a few more instances of "const unsigned char *" to USPTR, making
1506        the feature of a custom pointer more persuasive (as requested by a user).
1507    
1508    27. Wrapped the definitions of fileno and isatty for Windows, which appear in
1509        pcretest.c, inside #ifndefs, because it seems they are sometimes already
1510        pre-defined.
1511    
1512    28. Added support for (*UTF8) at the start of a pattern.
1513    
1514    29. Arrange for flags added by the "release type" setting in CMake to be shown
1515        in the configuration summary.
1516    
1517    
1518    Version 7.8 05-Sep-08
1519    ---------------------
1520    
1521    1.  Replaced UCP searching code with optimized version as implemented for Ad
1522        Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
1523        stage table and inline lookup instead of a function, giving speed ups of 2
1524        to 5 times on some simple patterns that I tested. Permission was given to
1525        distribute the MultiStage2.py script that generates the tables (it's not in
1526        the tarball, but is in the Subversion repository).
1527    
1528    2.  Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
1529        scripts.
1530    
1531    3.  Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
1532        a group with a zero qualifier. The result of the study could be incorrect,
1533        or the function might crash, depending on the pattern.
1534    
1535    4.  Caseless matching was not working for non-ASCII characters in back
1536        references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
1537        It now works when Unicode Property Support is available.
1538    
1539    5.  In pcretest, an escape such as \x{de} in the data was always generating
1540        a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
1541        non-UTF-8 mode. If the value is greater than 255, it gives a warning about
1542        truncation.
1543    
1544    6.  Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
1545    
1546    7.  Added two (int) casts to pcregrep when printing the difference of two
1547        pointers, in case they are 64-bit values.
1548    
1549    8.  Added comments about Mac OS X stack usage to the pcrestack man page and to
1550        test 2 if it fails.
1551    
1552    9.  Added PCRE_CALL_CONVENTION just before the names of all exported functions,
1553        and a #define of that name to empty if it is not externally set. This is to
1554        allow users of MSVC to set it if necessary.
1555    
1556    10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
1557        the convenience functions in the pcre_get.c source file.
1558    
1559    11. An option change at the start of a pattern that had top-level alternatives
1560        could cause overwriting and/or a crash. This command provoked a crash in
1561        some environments:
1562    
1563          printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
1564    
1565        This potential security problem was recorded as CVE-2008-2371.
1566    
1567    12. For a pattern where the match had to start at the beginning or immediately
1568        after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
1569        pcre_dfa_exec() could read past the end of the passed subject if there was
1570        no match. To help with detecting such bugs (e.g. with valgrind), I modified
1571        pcretest so that it places the subject at the end of its malloc-ed buffer.
1572    
1573    13. The change to pcretest in 12 above threw up a couple more cases when pcre_
1574        exec() might read past the end of the data buffer in UTF-8 mode.
1575    
1576    14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
1577        the data contained the byte 0x85 as part of a UTF-8 character within its
1578        first line. This applied both to normal and DFA matching.
1579    
1580    15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
1581        /^[^d]*?$/8 failed to match "abc".
1582    
1583    16. Added a missing copyright notice to pcrecpp_internal.h.
1584    
1585    17. Make it more clear in the documentation that values returned from
1586        pcre_exec() in ovector are byte offsets, not character counts.
1587    
1588    18. Tidied a few places to stop certain compilers from issuing warnings.
1589    
1590    19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
1591        supplied by Stefan Weber. I made a further small update for 7.8 because
1592        there is a change of source arrangements: the pcre_searchfuncs.c module is
1593        replaced by pcre_ucd.c.
1594    
1595    
1596    Version 7.7 07-May-08
1597    ---------------------
1598    
1599    1.  Applied Craig's patch to sort out a long long problem: "If we can't convert
1600        a string to a long long, pretend we don't even have a long long." This is
1601        done by checking for the strtoq, strtoll, and _strtoi64 functions.
1602    
1603    2.  Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
1604        pre-7.6 versions, which defined a global no_arg variable instead of putting
1605        it in the RE class. (See also #8 below.)
1606    
1607    3.  Remove a line of dead code, identified by coverity and reported by Nuno
1608        Lopes.
1609    
1610    4.  Fixed two related pcregrep bugs involving -r with --include or --exclude:
1611    
1612        (1) The include/exclude patterns were being applied to the whole pathnames
1613            of files, instead of just to the final components.
1614    
1615        (2) If there was more than one level of directory, the subdirectories were
1616            skipped unless they satisfied the include/exclude conditions. This is
1617            inconsistent with GNU grep (and could even be seen as contrary to the
1618            pcregrep specification - which I improved to make it absolutely clear).
1619            The action now is always to scan all levels of directory, and just
1620            apply the include/exclude patterns to regular files.
1621    
1622    5.  Added the --include_dir and --exclude_dir patterns to pcregrep, and used
1623        --exclude_dir in the tests to avoid scanning .svn directories.
1624    
1625    6.  Applied Craig's patch to the QuoteMeta function so that it escapes the
1626        NUL character as backslash + 0 rather than backslash + NUL, because PCRE
1627        doesn't support NULs in patterns.
1628    
1629    7.  Added some missing "const"s to declarations of static tables in
1630        pcre_compile.c and pcre_dfa_exec.c.
1631    
1632    8.  Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
1633        caused by fix #2  above. (Subsequently also a second patch to fix the
1634        first patch. And a third patch - this was a messy problem.)
1635    
1636    9.  Applied Craig's patch to remove the use of push_back().
1637    
1638    10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
1639        matching function regexec().
1640    
1641    11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
1642        which, however, unlike Perl's \g{...}, are subroutine calls, not back
1643        references. PCRE supports relative numbers with this syntax (I don't think
1644        Oniguruma does).
1645    
1646    12. Previously, a group with a zero repeat such as (...){0} was completely
1647        omitted from the compiled regex. However, this means that if the group
1648        was called as a subroutine from elsewhere in the pattern, things went wrong
1649        (an internal error was given). Such groups are now left in the compiled
1650        pattern, with a new opcode that causes them to be skipped at execution
1651        time.
1652    
1653    13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
1654        to the way PCRE behaves:
1655    
1656        (a) A lone ] character is dis-allowed (Perl treats it as data).
1657    
1658        (b) A back reference to an unmatched subpattern matches an empty string
1659            (Perl fails the current match path).
1660    
1661        (c) A data ] in a character class must be notated as \] because if the
1662            first data character in a class is ], it defines an empty class. (In
1663            Perl it is not possible to have an empty class.) The empty class []
1664            never matches; it forces failure and is equivalent to (*FAIL) or (?!).
1665            The negative empty class [^] matches any one character, independently
1666            of the DOTALL setting.
1667    
1668    14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
1669        non-existent subpattern following a character class starting with ']' and
1670        containing () gave an internal compiling error instead of "reference to
1671        non-existent subpattern". Fortunately, when the pattern did exist, the
1672        compiled code was correct. (When scanning forwards to check for the
1673        existencd of the subpattern, it was treating the data ']' as terminating
1674        the class, so got the count wrong. When actually compiling, the reference
1675        was subsequently set up correctly.)
1676    
1677    15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
1678        it was being rejected as not supported by pcre_dfa_exec(), even though
1679        other assertions are supported. I have made pcre_dfa_exec() support
1680        (*FAIL).
1681    
1682    16. The implementation of 13c above involved the invention of a new opcode,
1683        OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
1684        cannot be changed at match time, I realized I could make a small
1685        improvement to matching performance by compiling OP_ALLANY instead of
1686        OP_ANY for "." when DOTALL was set, and then removing the runtime tests
1687        on the OP_ANY path.
1688    
1689    17. Compiling pcretest on Windows with readline support failed without the
1690        following two fixes: (1) Make the unistd.h include conditional on
1691        HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
1692    
1693    18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
1694        ncurses library to be included for pcretest when ReadLine support is
1695        requested, but also to allow for it to be overridden. This patch came from
1696        Daniel Bergström.
1697    
1698    19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
1699        as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
1700        any errors with the current Unicode tables. Thanks to Peter Kankowski for
1701        spotting this.
1702    
1703    
1704    Version 7.6 28-Jan-08
1705    ---------------------
1706    
1707    1.  A character class containing a very large number of characters with
1708        codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
1709        overflow.
1710    
1711    2.  Patch to cut out the "long long" test in pcrecpp_unittest when
1712        HAVE_LONG_LONG is not defined.
1713    
1714    3.  Applied Christian Ehrlicher's patch to update the CMake build files to
1715        bring them up to date and include new features. This patch includes:
1716    
1717        - Fixed PH's badly added libz and libbz2 support.
1718        - Fixed a problem with static linking.
1719        - Added pcredemo. [But later removed - see 7 below.]
1720        - Fixed dftables problem and added an option.
1721        - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
1722            HAVE_LONG_LONG.
1723        - Added readline support for pcretest.
1724        - Added an listing of the option settings after cmake has run.
1725    
1726    4.  A user submitted a patch to Makefile that makes it easy to create
1727        "pcre.dll" under mingw when using Configure/Make. I added stuff to
1728        Makefile.am that cause it to include this special target, without
1729        affecting anything else. Note that the same mingw target plus all
1730        the other distribution libraries and programs are now supported
1731        when configuring with CMake (see 6 below) instead of with
1732        Configure/Make.
1733    
1734    5.  Applied Craig's patch that moves no_arg into the RE class in the C++ code.
1735        This is an attempt to solve the reported problem "pcrecpp::no_arg is not
1736        exported in the Windows port". It has not yet been confirmed that the patch
1737        solves the problem, but it does no harm.
1738    
1739    6.  Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
1740        NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
1741        with CMake, and also correct the comment about stack recursion.
1742    
1743    7.  Remove the automatic building of pcredemo from the ./configure system and
1744        from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
1745        of a program that users should build themselves after PCRE is installed, so
1746        building it automatically is not really right. What is more, it gave
1747        trouble in some build environments.
1748    
1749    8.  Further tidies to CMakeLists.txt from Sheri and Christian.
1750    
1751    
1752    Version 7.5 10-Jan-08
1753    ---------------------
1754    
1755    1.  Applied a patch from Craig: "This patch makes it possible to 'ignore'
1756        values in parens when parsing an RE using the C++ wrapper."
1757    
1758    2.  Negative specials like \S did not work in character classes in UTF-8 mode.
1759        Characters greater than 255 were excluded from the class instead of being
1760        included.
1761    
1762    3.  The same bug as (2) above applied to negated POSIX classes such as
1763        [:^space:].
1764    
1765    4.  PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
1766        defined or documented. It seems to have been a typo for PCRE_STATIC, so
1767        I have changed it.
1768    
1769    5.  The construct (?&) was not diagnosed as a syntax error (it referenced the
1770        first named subpattern) and a construct such as (?&a) would reference the
1771        first named subpattern whose name started with "a" (in other words, the
1772        length check was missing). Both these problems are fixed. "Subpattern name
1773        expected" is now given for (?&) (a zero-length name), and this patch also
1774        makes it give the same error for \k'' (previously it complained that that
1775        was a reference to a non-existent subpattern).
1776    
1777    6.  The erroneous patterns (?+-a) and (?-+a) give different error messages;
1778        this is right because (?- can be followed by option settings as well as by
1779        digits. I have, however, made the messages clearer.
1780    
1781    7.  Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
1782        than the number used in the conditional) now cause a compile-time error.
1783        This is actually not compatible with Perl, which accepts such patterns, but
1784        treats the conditional as always being FALSE (as PCRE used to), but it
1785        seems to me that giving a diagnostic is better.
1786    
1787    8.  Change "alphameric" to the more common word "alphanumeric" in comments
1788        and messages.
1789    
1790    9.  Fix two occurrences of "backslash" in comments that should have been
1791        "backspace".
1792    
1793    10. Remove two redundant lines of code that can never be obeyed (their function
1794        was moved elsewhere).
1795    
1796    11. The program that makes PCRE's Unicode character property table had a bug
1797        which caused it to generate incorrect table entries for sequences of
1798        characters that have the same character type, but are in different scripts.
1799        It amalgamated them into a single range, with the script of the first of
1800        them. In other words, some characters were in the wrong script. There were
1801        thirteen such cases, affecting characters in the following ranges:
1802    
1803          U+002b0 - U+002c1
1804          U+0060c - U+0060d
1805          U+0061e - U+00612
1806          U+0064b - U+0065e
1807          U+0074d - U+0076d
1808          U+01800 - U+01805
1809          U+01d00 - U+01d77
1810          U+01d9b - U+01dbf
1811          U+0200b - U+0200f
1812          U+030fc - U+030fe
1813          U+03260 - U+0327f
1814          U+0fb46 - U+0fbb1
1815          U+10450 - U+1049d
1816    
1817    12. The -o option (show only the matching part of a line) for pcregrep was not
1818        compatible with GNU grep in that, if there was more than one match in a
1819        line, it showed only the first of them. It now behaves in the same way as
1820        GNU grep.
1821    
1822    13. If the -o and -v options were combined for pcregrep, it printed a blank
1823        line for every non-matching line. GNU grep prints nothing, and pcregrep now
1824        does the same. The return code can be used to tell if there were any
1825        non-matching lines.
1826    
1827    14. Added --file-offsets and --line-offsets to pcregrep.
1828    
1829    15. The pattern (?=something)(?R) was not being diagnosed as a potentially
1830        infinitely looping recursion. The bug was that positive lookaheads were not
1831        being skipped when checking for a possible empty match (negative lookaheads
1832        and both kinds of lookbehind were skipped).
1833    
1834    16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
1835        inclusion of <windows.h> to before rather than after the definition of
1836        INVALID_FILE_ATTRIBUTES (patch from David Byron).
1837    
1838    17. Specifying a possessive quantifier with a specific limit for a Unicode
1839        character property caused pcre_compile() to compile bad code, which led at
1840        runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
1841        are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
1842        caused the error; without that there was no problem.
1843    
1844    18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
1845    
1846    19. Added --enable-pcretest-libreadline.
1847    
1848    20. In pcrecpp.cc, the variable 'count' was incremented twice in
1849        RE::GlobalReplace(). As a result, the number of replacements returned was
1850        double what it should be. I removed one of the increments, but Craig sent a
1851        later patch that removed the other one (the right fix) and added unit tests
1852        that check the return values (which was not done before).
1853    
1854    21. Several CMake things:
1855    
1856        (1) Arranged that, when cmake is used on Unix, the libraries end up with
1857            the names libpcre and libpcreposix, not just pcre and pcreposix.
1858    
1859        (2) The above change means that pcretest and pcregrep are now correctly
1860            linked with the newly-built libraries, not previously installed ones.
1861    
1862        (3) Added PCRE_SUPPORT_LIBREADLINE, PCRE_SUPPORT_LIBZ, PCRE_SUPPORT_LIBBZ2.
1863    
1864    22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
1865        crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
1866        UTF-8 newline character). The key issue is that the pattern starts .*;
1867        this means that the match must be either at the beginning, or after a
1868        newline. The bug was in the code for advancing after a failed match and
1869        checking that the new position followed a newline. It was not taking
1870        account of UTF-8 characters correctly.
1871    
1872    23. PCRE was behaving differently from Perl in the way it recognized POSIX
1873        character classes. PCRE was not treating the sequence [:...:] as a
1874        character class unless the ... were all letters. Perl, however, seems to
1875        allow any characters between [: and :], though of course it rejects as
1876        unknown any "names" that contain non-letters, because all the known class
1877        names consist only of letters. Thus, Perl gives an error for [[:1234:]],
1878        for example, whereas PCRE did not - it did not recognize a POSIX character
1879        class. This seemed a bit dangerous, so the code has been changed to be
1880        closer to Perl. The behaviour is not identical to Perl, because PCRE will
1881        diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
1882        treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
1883        Perl does, and where it didn't before.
1884    
1885    24. Rewrite so as to remove the single use of %n from pcregrep because in some
1886        Windows environments %n is disabled by default.
1887    
1888    
1889    Version 7.4 21-Sep-07
1890  ---------------------  ---------------------
1891    
1892  1.  Change 7.3/28 was implemented for classes by looking at the bitmap. This  1.  Change 7.3/28 was implemented for classes by looking at the bitmap. This
# Line 32  Version 7.4 10-Sep-07 Line 1917  Version 7.4 10-Sep-07
1917      compatibility, even though it is no longer used.      compatibility, even though it is no longer used.
1918    
1919  7.  Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and  7.  Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
1920      strtoull to pcrecpp.cc to select the available functions in WIN32 when the      strtoull to pcrecpp.cc to select the available functions in WIN32 when the
1921      windows.h file is present (where different names are used).      windows.h file is present (where different names are used). [This was
1922        reversed later after testing - see 16 below.]
1923    
1924  8.  Changed all #include <config.h> to #include "config.h". There were also  8.  Changed all #include <config.h> to #include "config.h". There were also
1925      some further <pcre.h> cases that I changed to "pcre.h".      some further <pcre.h> cases that I changed to "pcre.h".
# Line 60  Version 7.4 10-Sep-07 Line 1946  Version 7.4 10-Sep-07
1946    
1947  12. Updated the tests so that they work when \R is defaulted to ANYCRLF.  12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
1948    
1949    13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
1950        checked only for CRLF.
1951    
1952    14. Added casts to pcretest.c to avoid compiler warnings.
1953    
1954    15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
1955    
1956    16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
1957        and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
1958        entirely. This removes changes made in 7 above.
1959    
1960    17. The CMake files have been updated, and there is now more information about
1961        building with CMake in the NON-UNIX-USE document.
1962    
1963    
1964  Version 7.3 28-Aug-07  Version 7.3 28-Aug-07
1965  ---------------------  ---------------------

Legend:
Removed from v.248  
changed lines
  Added in v.1040

  ViewVC Help
Powered by ViewVC 1.1.5