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

Diff of /code/trunk/ChangeLog

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

revision 545 by ph10, Wed Jun 16 10:51:15 2010 UTC revision 1050 by chpe, Sun Sep 30 18:20:10 2012 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 8.10 16-Jun-2010  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    20. Turn case lists for horizontal and vertical white space into macros so that
87        they are defined only once.
88    
89    21. This set of changes together give more compatible Unicode case-folding
90        behaviour for characters that have more than one other case when UCP
91        support is available.
92    
93        (a) The Unicode property table now has offsets into a new table of sets of
94            three or more characters that are case-equivalent. The MultiStage2.py
95            script that generates these tables (the pcre_ucd.c file) now scans
96            CaseFolding.txt instead of UnicodeData.txt for character case
97            information.
98    
99        (b) The code for adding characters or ranges of characters to a character
100            class has been abstracted into a generalized function that also handles
101            case-independence. In UTF-mode with UCP support, this uses the new data
102            to handle characters with more than one other case.
103    
104        (c) A bug that is fixed as a result of (b) is that codepoints less than 256
105            whose other case is greater than 256 are now correctly matched
106            caselessly. Previously, the high codepoint matched the low one, but not
107            vice versa.
108    
109        (d) The processing of \h, \H, \v, and \ in character classes now makes use
110            of the new class addition function, using character lists defined as
111            macros alongside the case definitions of 20 above.
112    
113        (e) Caseless back references now work with characters that have more than
114            one other case.
115    
116        (f) General caseless matching of characters with more than one other case
117            is supported.
118    
119    22. Unicode character properties were updated from Unicode 6.2.0
120    
121    Version 8.31 06-July-2012
122    -------------------------
123    
124    1.  Fixing a wrong JIT test case and some compiler warnings.
125    
126    2.  Removed a bashism from the RunTest script.
127    
128    3.  Add a cast to pcre_exec.c to fix the warning "unary minus operator applied
129        to unsigned type, result still unsigned" that was given by an MS compiler
130        on encountering the code "-sizeof(xxx)".
131    
132    4.  Partial matching support is added to the JIT compiler.
133    
134    5.  Fixed several bugs concerned with partial matching of items that consist
135        of more than one character:
136    
137        (a) /^(..)\1/ did not partially match "aba" because checking references was
138            done on an "all or nothing" basis. This also applied to repeated
139            references.
140    
141        (b) \R did not give a hard partial match if \r was found at the end of the
142            subject.
143    
144        (c) \X did not give a hard partial match after matching one or more
145            characters at the end of the subject.
146    
147        (d) When newline was set to CRLF, a pattern such as /a$/ did not recognize
148            a partial match for the string "\r".
149    
150        (e) When newline was set to CRLF, the metacharacter "." did not recognize
151            a partial match for a CR character at the end of the subject string.
152    
153    6.  If JIT is requested using /S++ or -s++ (instead of just /S+ or -s+) when
154        running pcretest, the text "(JIT)" added to the output whenever JIT is
155        actually used to run the match.
156    
157    7.  Individual JIT compile options can be set in pcretest by following -s+[+]
158        or /S+[+] with a digit between 1 and 7.
159    
160    8.  OP_NOT now supports any UTF character not just single-byte ones.
161    
162    9.  (*MARK) control verb is now supported by the JIT compiler.
163    
164    10. The command "./RunTest list" lists the available tests without actually
165        running any of them. (Because I keep forgetting what they all are.)
166    
167    11. Add PCRE_INFO_MAXLOOKBEHIND.
168    
169    12. Applied a (slightly modified) user-supplied patch that improves performance
170        when the heap is used for recursion (compiled with --disable-stack-for-
171        recursion). Instead of malloc and free for each heap frame each time a
172        logical recursion happens, frames are retained on a chain and re-used where
173        possible. This sometimes gives as much as 30% improvement.
174    
175    13. As documented, (*COMMIT) is now confined to within a recursive subpattern
176        call.
177    
178    14. As documented, (*COMMIT) is now confined to within a positive assertion.
179    
180    15. It is now possible to link pcretest with libedit as an alternative to
181        libreadline.
182    
183    16. (*COMMIT) control verb is now supported by the JIT compiler.
184    
185    17. The Unicode data tables have been updated to Unicode 6.1.0.
186    
187    18. Added --file-list option to pcregrep.
188    
189    19. Added binary file support to pcregrep, including the -a, --binary-files,
190        -I, and --text options.
191    
192    20. The madvise function is renamed for posix_madvise for QNX compatibility
193        reasons. Fixed by Giuseppe D'Angelo.
194    
195    21. Fixed a bug for backward assertions with REVERSE 0 in the JIT compiler.
196    
197    22. Changed the option for creating symbolic links for 16-bit man pages from
198        -s to -sf so that re-installing does not cause issues.
199    
200    23. Support PCRE_NO_START_OPTIMIZE in JIT as (*MARK) support requires it.
201    
202    24. Fixed a very old bug in pcretest that caused errors with restarted DFA
203        matches in certain environments (the workspace was not being correctly
204        retained). Also added to pcre_dfa_exec() a simple plausibility check on
205        some of the workspace data at the beginning of a restart.
206    
207    25. \s*\R was auto-possessifying the \s* when it should not, whereas \S*\R
208        was not doing so when it should - probably a typo introduced by SVN 528
209        (change 8.10/14).
210    
211    26. When PCRE_UCP was not set, \w+\x{c4} was incorrectly auto-possessifying the
212        \w+ when the character tables indicated that \x{c4} was a word character.
213        There were several related cases, all because the tests for doing a table
214        lookup were testing for characters less than 127 instead of 255.
215    
216    27. If a pattern contains capturing parentheses that are not used in a match,
217        their slots in the ovector are set to -1. For those that are higher than
218        any matched groups, this happens at the end of processing. In the case when
219        there were back references that the ovector was too small to contain
220        (causing temporary malloc'd memory to be used during matching), and the
221        highest capturing number was not used, memory off the end of the ovector
222        was incorrectly being set to -1. (It was using the size of the temporary
223        memory instead of the true size.)
224    
225    28. To catch bugs like 27 using valgrind, when pcretest is asked to specify an
226        ovector size, it uses memory at the end of the block that it has got.
227    
228    29. Check for an overlong MARK name and give an error at compile time. The
229        limit is 255 for the 8-bit library and 65535 for the 16-bit library.
230    
231    30. JIT compiler update.
232    
233    31. JIT is now supported on jailbroken iOS devices. Thanks for Ruiger
234        Rill for the patch.
235    
236    32. Put spaces around SLJIT_PRINT_D in the JIT compiler. Required by CXX11.
237    
238    33. Variable renamings in the PCRE-JIT compiler. No functionality change.
239    
240    34. Fixed typos in pcregrep: in two places there was SUPPORT_LIBZ2 instead of
241        SUPPORT_LIBBZ2. This caused a build problem when bzip2 but not gzip (zlib)
242        was enabled.
243    
244    35. Improve JIT code generation for greedy plus quantifier.
245    
246    36. When /((?:a?)*)*c/ or /((?>a?)*)*c/ was matched against "aac", it set group
247        1 to "aa" instead of to an empty string. The bug affected repeated groups
248        that could potentially match an empty string.
249    
250    37. Optimizing single character iterators in JIT.
251    
252    38. Wide characters specified with \uxxxx in JavaScript mode are now subject to
253        the same checks as \x{...} characters in non-JavaScript mode. Specifically,
254        codepoints that are too big for the mode are faulted, and in a UTF mode,
255        disallowed codepoints are also faulted.
256    
257    39. If PCRE was compiled with UTF support, in three places in the DFA
258        matcher there was code that should only have been obeyed in UTF mode, but
259        was being obeyed unconditionally. In 8-bit mode this could cause incorrect
260        processing when bytes with values greater than 127 were present. In 16-bit
261        mode the bug would be provoked by values in the range 0xfc00 to 0xdc00. In
262        both cases the values are those that cannot be the first data item in a UTF
263        character. The three items that might have provoked this were recursions,
264        possessively repeated groups, and atomic groups.
265    
266    40. Ensure that libpcre is explicitly listed in the link commands for pcretest
267        and pcregrep, because some OS require shared objects to be explicitly
268        passed to ld, causing the link step to fail if they are not.
269    
270    41. There were two incorrect #ifdefs in pcre_study.c, meaning that, in 16-bit
271        mode, patterns that started with \h* or \R* might be incorrectly matched.
272    
273    
274    Version 8.30 04-February-2012
275    -----------------------------
276    
277    1.  Renamed "isnumber" as "is_a_number" because in some Mac environments this
278        name is defined in ctype.h.
279    
280    2.  Fixed a bug in fixed-length calculation for lookbehinds that would show up
281        only in quite long subpatterns.
282    
283    3.  Removed the function pcre_info(), which has been obsolete and deprecated
284        since it was replaced by pcre_fullinfo() in February 2000.
285    
286    4.  For a non-anchored pattern, if (*SKIP) was given with a name that did not
287        match a (*MARK), and the match failed at the start of the subject, a
288        reference to memory before the start of the subject could occur. This bug
289        was introduced by fix 17 of release 8.21.
290    
291    5.  A reference to an unset group with zero minimum repetition was giving
292        totally wrong answers (in non-JavaScript-compatibility mode). For example,
293        /(another)?(\1?)test/ matched against "hello world test". This bug was
294        introduced in release 8.13.
295    
296    6.  Add support for 16-bit character strings (a large amount of work involving
297        many changes and refactorings).
298    
299    7.  RunGrepTest failed on msys because \r\n was replaced by whitespace when the
300        command "pattern=`printf 'xxx\r\njkl'`" was run. The pattern is now taken
301        from a file.
302    
303    8.  Ovector size of 2 is also supported by JIT based pcre_exec (the ovector size
304        rounding is not applied in this particular case).
305    
306    9.  The invalid Unicode surrogate codepoints U+D800 to U+DFFF are now rejected
307        if they appear, or are escaped, in patterns.
308    
309    10. Get rid of a number of -Wunused-but-set-variable warnings.
310    
311    11. The pattern /(?=(*:x))(q|)/ matches an empty string, and returns the mark
312        "x". The similar pattern /(?=(*:x))((*:y)q|)/ did not return a mark at all.
313        Oddly, Perl behaves the same way. PCRE has been fixed so that this pattern
314        also returns the mark "x". This bug applied to capturing parentheses,
315        non-capturing parentheses, and atomic parentheses. It also applied to some
316        assertions.
317    
318    12. Stephen Kelly's patch to CMakeLists.txt allows it to parse the version
319        information out of configure.ac instead of relying on pcre.h.generic, which
320        is not stored in the repository.
321    
322    13. Applied Dmitry V. Levin's patch for a more portable method for linking with
323        -lreadline.
324    
325    14. ZH added PCRE_CONFIG_JITTARGET; added its output to pcretest -C.
326    
327    15. Applied Graycode's patch to put the top-level frame on the stack rather
328        than the heap when not using the stack for recursion. This gives a
329        performance improvement in many cases when recursion is not deep.
330    
331    16. Experimental code added to "pcretest -C" to output the stack frame size.
332    
333    
334    Version 8.21 12-Dec-2011
335    ------------------------
336    
337    1.  Updating the JIT compiler.
338    
339    2.  JIT compiler now supports OP_NCREF, OP_RREF and OP_NRREF. New test cases
340        are added as well.
341    
342    3.  Fix cache-flush issue on PowerPC (It is still an experimental JIT port).
343        PCRE_EXTRA_TABLES is not suported by JIT, and should be checked before
344        calling _pcre_jit_exec. Some extra comments are added.
345    
346    4.  (*MARK) settings inside atomic groups that do not contain any capturing
347        parentheses, for example, (?>a(*:m)), were not being passed out. This bug
348        was introduced by change 18 for 8.20.
349    
350    5.  Supporting of \x, \U and \u in JavaScript compatibility mode based on the
351        ECMA-262 standard.
352    
353    6.  Lookbehinds such as (?<=a{2}b) that contained a fixed repetition were
354        erroneously being rejected as "not fixed length" if PCRE_CASELESS was set.
355        This bug was probably introduced by change 9 of 8.13.
356    
357    7.  While fixing 6 above, I noticed that a number of other items were being
358        incorrectly rejected as "not fixed length". This arose partly because newer
359        opcodes had not been added to the fixed-length checking code. I have (a)
360        corrected the bug and added tests for these items, and (b) arranged for an
361        error to occur if an unknown opcode is encountered while checking for fixed
362        length instead of just assuming "not fixed length". The items that were
363        rejected were: (*ACCEPT), (*COMMIT), (*FAIL), (*MARK), (*PRUNE), (*SKIP),
364        (*THEN), \h, \H, \v, \V, and single character negative classes with fixed
365        repetitions, e.g. [^a]{3}, with and without PCRE_CASELESS.
366    
367    8.  A possessively repeated conditional subpattern such as (?(?=c)c|d)++ was
368        being incorrectly compiled and would have given unpredicatble results.
369    
370    9.  A possessively repeated subpattern with minimum repeat count greater than
371        one behaved incorrectly. For example, (A){2,}+ behaved as if it was
372        (A)(A)++ which meant that, after a subsequent mismatch, backtracking into
373        the first (A) could occur when it should not.
374    
375    10. Add a cast and remove a redundant test from the code.
376    
377    11. JIT should use pcre_malloc/pcre_free for allocation.
378    
379    12. Updated pcre-config so that it no longer shows -L/usr/lib, which seems
380        best practice nowadays, and helps with cross-compiling. (If the exec_prefix
381        is anything other than /usr, -L is still shown).
382    
383    13. In non-UTF-8 mode, \C is now supported in lookbehinds and DFA matching.
384    
385    14. Perl does not support \N without a following name in a [] class; PCRE now
386        also gives an error.
387    
388    15. If a forward reference was repeated with an upper limit of around 2000,
389        it caused the error "internal error: overran compiling workspace". The
390        maximum number of forward references (including repeats) was limited by the
391        internal workspace, and dependent on the LINK_SIZE. The code has been
392        rewritten so that the workspace expands (via pcre_malloc) if necessary, and
393        the default depends on LINK_SIZE. There is a new upper limit (for safety)
394        of around 200,000 forward references. While doing this, I also speeded up
395        the filling in of repeated forward references.
396    
397    16. A repeated forward reference in a pattern such as (a)(?2){2}(.) was
398        incorrectly expecting the subject to contain another "a" after the start.
399    
400    17. When (*SKIP:name) is activated without a corresponding (*MARK:name) earlier
401        in the match, the SKIP should be ignored. This was not happening; instead
402        the SKIP was being treated as NOMATCH. For patterns such as
403        /A(*MARK:A)A+(*SKIP:B)Z|AAC/ this meant that the AAC branch was never
404        tested.
405    
406    18. The behaviour of (*MARK), (*PRUNE), and (*THEN) has been reworked and is
407        now much more compatible with Perl, in particular in cases where the result
408        is a non-match for a non-anchored pattern. For example, if
409        /b(*:m)f|a(*:n)w/ is matched against "abc", the non-match returns the name
410        "m", where previously it did not return a name. A side effect of this
411        change is that for partial matches, the last encountered mark name is
412        returned, as for non matches. A number of tests that were previously not
413        Perl-compatible have been moved into the Perl-compatible test files. The
414        refactoring has had the pleasing side effect of removing one argument from
415        the match() function, thus reducing its stack requirements.
416    
417    19. If the /S+ option was used in pcretest to study a pattern using JIT,
418        subsequent uses of /S (without +) incorrectly behaved like /S+.
419    
420    21. Retrieve executable code size support for the JIT compiler and fixing
421        some warnings.
422    
423    22. A caseless match of a UTF-8 character whose other case uses fewer bytes did
424        not work when the shorter character appeared right at the end of the
425        subject string.
426    
427    23. Added some (int) casts to non-JIT modules to reduce warnings on 64-bit
428        systems.
429    
430    24. Added PCRE_INFO_JITSIZE to pass on the value from (21) above, and also
431        output it when the /M option is used in pcretest.
432    
433    25. The CheckMan script was not being included in the distribution. Also, added
434        an explicit "perl" to run Perl scripts from the PrepareRelease script
435        because this is reportedly needed in Windows.
436    
437    26. If study data was being save in a file and studying had not found a set of
438        "starts with" bytes for the pattern, the data written to the file (though
439        never used) was taken from uninitialized memory and so caused valgrind to
440        complain.
441    
442    27. Updated RunTest.bat as provided by Sheri Pierce.
443    
444    28. Fixed a possible uninitialized memory bug in pcre_jit_compile.c.
445    
446    29. Computation of memory usage for the table of capturing group names was
447        giving an unnecessarily large value.
448    
449    
450    Version 8.20 21-Oct-2011
451    ------------------------
452    
453    1.  Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
454        a POSIX class. After further experiments with Perl, which convinced me that
455        Perl has bugs and confusions, a closing square bracket is no longer allowed
456        in a POSIX name. This bug also affected patterns with classes that started
457        with full stops.
458    
459    2.  If a pattern such as /(a)b|ac/ is matched against "ac", there is no
460        captured substring, but while checking the failing first alternative,
461        substring 1 is temporarily captured. If the output vector supplied to
462        pcre_exec() was not big enough for this capture, the yield of the function
463        was still zero ("insufficient space for captured substrings"). This cannot
464        be totally fixed without adding another stack variable, which seems a lot
465        of expense for a edge case. However, I have improved the situation in cases
466        such as /(a)(b)x|abc/ matched against "abc", where the return code
467        indicates that fewer than the maximum number of slots in the ovector have
468        been set.
469    
470    3.  Related to (2) above: when there are more back references in a pattern than
471        slots in the output vector, pcre_exec() uses temporary memory during
472        matching, and copies in the captures as far as possible afterwards. It was
473        using the entire output vector, but this conflicts with the specification
474        that only 2/3 is used for passing back captured substrings. Now it uses
475        only the first 2/3, for compatibility. This is, of course, another edge
476        case.
477    
478    4.  Zoltan Herczeg's just-in-time compiler support has been integrated into the
479        main code base, and can be used by building with --enable-jit. When this is
480        done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
481        runtime --no-jit option is given.
482    
483    5.  When the number of matches in a pcre_dfa_exec() run exactly filled the
484        ovector, the return from the function was zero, implying that there were
485        other matches that did not fit. The correct "exactly full" value is now
486        returned.
487    
488    6.  If a subpattern that was called recursively or as a subroutine contained
489        (*PRUNE) or any other control that caused it to give a non-standard return,
490        invalid errors such as "Error -26 (nested recursion at the same subject
491        position)" or even infinite loops could occur.
492    
493    7.  If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
494        computing the minimum length on reaching *ACCEPT, and so ended up with the
495        wrong value of 1 rather than 0. Further investigation indicates that
496        computing a minimum subject length in the presence of *ACCEPT is difficult
497        (think back references, subroutine calls), and so I have changed the code
498        so that no minimum is registered for a pattern that contains *ACCEPT.
499    
500    8.  If (*THEN) was present in the first (true) branch of a conditional group,
501        it was not handled as intended. [But see 16 below.]
502    
503    9.  Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
504        Sheri Pierce.
505    
506    10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
507        the first byte in a match must be "a".
508    
509    11. Change 17 for 8.13 increased the recursion depth for patterns like
510        /a(?:.)*?a/ drastically. I've improved things by remembering whether a
511        pattern contains any instances of (*THEN). If it does not, the old
512        optimizations are restored. It would be nice to do this on a per-group
513        basis, but at the moment that is not feasible.
514    
515    12. In some environments, the output of pcretest -C is CRLF terminated. This
516        broke RunTest's code that checks for the link size. A single white space
517        character after the value is now allowed for.
518    
519    13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
520        For "fr", it uses the Windows-specific input and output files.
521    
522    14. If (*THEN) appeared in a group that was called recursively or as a
523        subroutine, it did not work as intended. [But see next item.]
524    
525    15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
526        pattern fragments (but not containing any | characters). If A and B are
527        matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
528        was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
529        D. In other words, Perl considers parentheses that do not contain any |
530        characters to be part of a surrounding alternative, whereas PCRE was
531        treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
532        differently. PCRE now behaves in the same way as Perl, except in the case
533        of subroutine/recursion calls such as (?1) which have in any case always
534        been different (but PCRE had them first :-).
535    
536    16. Related to 15 above: Perl does not treat the | in a conditional group as
537        creating alternatives. Such a group is treated in the same way as an
538        ordinary group without any | characters when processing (*THEN). PCRE has
539        been changed to match Perl's behaviour.
540    
541    17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
542        RunGrepTest script failed.
543    
544    18. Change 22 for version 13 caused atomic groups to use more stack. This is
545        inevitable for groups that contain captures, but it can lead to a lot of
546        stack use in large patterns. The old behaviour has been restored for atomic
547        groups that do not contain any capturing parentheses.
548    
549    19. If the PCRE_NO_START_OPTIMIZE option was set for pcre_compile(), it did not
550        suppress the check for a minimum subject length at run time. (If it was
551        given to pcre_exec() or pcre_dfa_exec() it did work.)
552    
553    20. Fixed an ASCII-dependent infelicity in pcretest that would have made it
554        fail to work when decoding hex characters in data strings in EBCDIC
555        environments.
556    
557    21. It appears that in at least one Mac OS environment, the isxdigit() function
558        is implemented as a macro that evaluates to its argument more than once,
559        contravening the C 90 Standard (I haven't checked a later standard). There
560        was an instance in pcretest which caused it to go wrong when processing
561        \x{...} escapes in subject strings. The has been rewritten to avoid using
562        things like p++ in the argument of isxdigit().
563    
564    
565    Version 8.13 16-Aug-2011
566    ------------------------
567    
568    1.  The Unicode data tables have been updated to Unicode 6.0.0.
569    
570    2.  Two minor typos in pcre_internal.h have been fixed.
571    
572    3.  Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
573        pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
574        in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
575    
576    4.  There were a number of related bugs in the code for matching backrefences
577        caselessly in UTF-8 mode when codes for the characters concerned were
578        different numbers of bytes. For example, U+023A and U+2C65 are an upper
579        and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
580        (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
581        code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
582        2-byte code at the end of the subject (it thought there wasn't enough data
583        left).
584    
585    5.  Comprehensive information about what went wrong is now returned by
586        pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
587        as the output vector has at least 2 elements. The offset of the start of
588        the failing character and a reason code are placed in the vector.
589    
590    6.  When the UTF-8 string check fails for pcre_compile(), the offset that is
591        now returned is for the first byte of the failing character, instead of the
592        last byte inspected. This is an incompatible change, but I hope it is small
593        enough not to be a problem. It makes the returned offset consistent with
594        pcre_exec() and pcre_dfa_exec().
595    
596    7.  pcretest now gives a text phrase as well as the error number when
597        pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
598        failure, the offset and reason code are output.
599    
600    8.  When \R was used with a maximizing quantifier it failed to skip backwards
601        over a \r\n pair if the subsequent match failed. Instead, it just skipped
602        back over a single character (\n). This seems wrong (because it treated the
603        two characters as a single entity when going forwards), conflicts with the
604        documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
605        behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
606        has been changed.
607    
608    9.  Some internal refactoring has changed the processing so that the handling
609        of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
610        time (the PCRE_DOTALL option was changed this way some time ago: version
611        7.7 change 16). This has made it possible to abolish the OP_OPT op code,
612        which was always a bit of a fudge. It also means that there is one less
613        argument for the match() function, which reduces its stack requirements
614        slightly. This change also fixes an incompatibility with Perl: the pattern
615        (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
616    
617    10. More internal refactoring has drastically reduced the number of recursive
618        calls to match() for possessively repeated groups such as (abc)++ when
619        using pcre_exec().
620    
621    11. While implementing 10, a number of bugs in the handling of groups were
622        discovered and fixed:
623    
624        (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
625        (a|)*(?1) gave a compile-time internal error.
626        ((a|)+)+  did not notice that the outer group could match an empty string.
627        (^a|^)+   was not marked as anchored.
628        (.*a|.*)+ was not marked as matching at start or after a newline.
629    
630    12. Yet more internal refactoring has removed another argument from the match()
631        function. Special calls to this function are now indicated by setting a
632        value in a variable in the "match data" data block.
633    
634    13. Be more explicit in pcre_study() instead of relying on "default" for
635        opcodes that mean there is no starting character; this means that when new
636        ones are added and accidentally left out of pcre_study(), testing should
637        pick them up.
638    
639    14. The -s option of pcretest has been documented for ages as being an old
640        synonym of -m (show memory usage). I have changed it to mean "force study
641        for every regex", that is, assume /S for every regex. This is similar to -i
642        and -d etc. It's slightly incompatible, but I'm hoping nobody is still
643        using it. It makes it easier to run collections of tests with and without
644        study enabled, and thereby test pcre_study() more easily. All the standard
645        tests are now run with and without -s (but some patterns can be marked as
646        "never study" - see 20 below).
647    
648    15. When (*ACCEPT) was used in a subpattern that was called recursively, the
649        restoration of the capturing data to the outer values was not happening
650        correctly.
651    
652    16. If a recursively called subpattern ended with (*ACCEPT) and matched an
653        empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
654        pattern had matched an empty string, and so incorrectly returned a no
655        match.
656    
657    17. There was optimizing code for the last branch of non-capturing parentheses,
658        and also for the obeyed branch of a conditional subexpression, which used
659        tail recursion to cut down on stack usage. Unfortunately, now that there is
660        the possibility of (*THEN) occurring in these branches, tail recursion is
661        no longer possible because the return has to be checked for (*THEN). These
662        two optimizations have therefore been removed. [But see 8.20/11 above.]
663    
664    18. If a pattern containing \R was studied, it was assumed that \R always
665        matched two bytes, thus causing the minimum subject length to be
666        incorrectly computed because \R can also match just one byte.
667    
668    19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
669        was incorrectly computed.
670    
671    20. If /S is present twice on a test pattern in pcretest input, it now
672        *disables* studying, thereby overriding the use of -s on the command line
673        (see 14 above). This is necessary for one or two tests to keep the output
674        identical in both cases.
675    
676    21. When (*ACCEPT) was used in an assertion that matched an empty string and
677        PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
678    
679    22. When an atomic group that contained a capturing parenthesis was
680        successfully matched, but the branch in which it appeared failed, the
681        capturing was not being forgotten if a higher numbered group was later
682        captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
683        group 1 to "a", when in fact it should be unset. This applied to multi-
684        branched capturing and non-capturing groups, repeated or not, and also to
685        positive assertions (capturing in negative assertions does not happen
686        in PCRE) and also to nested atomic groups.
687    
688    23. Add the ++ qualifier feature to pcretest, to show the remainder of the
689        subject after a captured substring, to make it easier to tell which of a
690        number of identical substrings has been captured.
691    
692    24. The way atomic groups are processed by pcre_exec() has been changed so that
693        if they are repeated, backtracking one repetition now resets captured
694        values correctly. For example, if ((?>(a+)b)+aabab) is matched against
695        "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
696        "aaa". Previously, it would have been "a". As part of this code
697        refactoring, the way recursive calls are handled has also been changed.
698    
699    25. If an assertion condition captured any substrings, they were not passed
700        back unless some other capturing happened later. For example, if
701        (?(?=(a))a) was matched against "a", no capturing was returned.
702    
703    26. When studying a pattern that contained subroutine calls or assertions,
704        the code for finding the minimum length of a possible match was handling
705        direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
706        group 1 called group 2 while simultaneously a separate group 2 called group
707        1). A stack overflow occurred in this case. I have fixed this by limiting
708        the recursion depth to 10.
709    
710    27. Updated RunTest.bat in the distribution to the version supplied by Tom
711        Fortmann. This supports explicit test numbers on the command line, and has
712        argument validation and error reporting.
713    
714    28. An instance of \X with an unlimited repeat could fail if at any point the
715        first character it looked at was a mark character.
716    
717    29. Some minor code refactoring concerning Unicode properties and scripts
718        should reduce the stack requirement of match() slightly.
719    
720    30. Added the '=' option to pcretest to check the setting of unused capturing
721        slots at the end of the pattern, which are documented as being -1, but are
722        not included in the return count.
723    
724    31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
725        compiled something random. Now it gives a compile-time error (as does
726        Perl).
727    
728    32. A *MARK encountered during the processing of a positive assertion is now
729        recorded and passed back (compatible with Perl).
730    
731    33. If --only-matching or --colour was set on a pcregrep call whose pattern
732        had alternative anchored branches, the search for a second match in a line
733        was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
734        matched the line "0102" twice. The same bug affected patterns that started
735        with a backwards assertion. For example /\b01|\b02/ also matched "0102"
736        twice.
737    
738    34. Previously, PCRE did not allow quantification of assertions. However, Perl
739        does, and because of capturing effects, quantifying parenthesized
740        assertions may at times be useful. Quantifiers are now allowed for
741        parenthesized assertions.
742    
743    35. A minor code tidy in pcre_compile() when checking options for \R usage.
744    
745    36. \g was being checked for fancy things in a character class, when it should
746        just be a literal "g".
747    
748    37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
749        appearance of a nested POSIX class supersedes an apparent external class.
750        For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
751        unescaped square brackets may also appear as part of class names. For
752        example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
753        more like Perl. (But see 8.20/1 above.)
754    
755    38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
756        was because it thought it was \N{name}, which is not supported).
757    
758    39. Add minix to OS list not supporting the -S option in pcretest.
759    
760    40. PCRE tries to detect cases of infinite recursion at compile time, but it
761        cannot analyze patterns in sufficient detail to catch mutual recursions
762        such as ((?1))((?2)). There is now a runtime test that gives an error if a
763        subgroup is called recursively as a subpattern for a second time at the
764        same position in the subject string. In previous releases this might have
765        been caught by the recursion limit, or it might have run out of stack.
766    
767    41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
768        happen only once. PCRE was, however incorrectly giving a compile time error
769        "recursive call could loop indefinitely" because it cannot analyze the
770        pattern in sufficient detail. The compile time test no longer happens when
771        PCRE is compiling a conditional subpattern, but actual runaway loops are
772        now caught at runtime (see 40 above).
773    
774    42. It seems that Perl allows any characters other than a closing parenthesis
775        to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
776        has been changed to be the same.
777    
778    43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
779        as not to get warnings when autogen.sh is called. Also changed
780        AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
781    
782    44. To help people who use pcregrep to scan files containing exceedingly long
783        lines, the following changes have been made:
784    
785        (a) The default value of the buffer size parameter has been increased from
786            8K to 20K. (The actual buffer used is three times this size.)
787    
788        (b) The default can be changed by ./configure --with-pcregrep-bufsize when
789            PCRE is built.
790    
791        (c) A --buffer-size=n option has been added to pcregrep, to allow the size
792            to be set at run time.
793    
794        (d) Numerical values in pcregrep options can be followed by K or M, for
795            example --buffer-size=50K.
796    
797        (e) If a line being scanned overflows pcregrep's buffer, an error is now
798            given and the return code is set to 2.
799    
800    45. Add a pointer to the latest mark to the callout data block.
801    
802    46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
803        partial match of an empty string instead of no match. This was specific to
804        the use of ".".
805    
806    47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
807        complete match instead of a partial match. This bug was dependent on both
808        the PCRE_UTF8 and PCRE_DOTALL options being set.
809    
810    48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
811        starting byte set, because \b was not being ignored.
812    
813    
814    Version 8.12 15-Jan-2011
815    ------------------------
816    
817    1.  Fixed some typos in the markup of the man pages, and wrote a script that
818        checks for such things as part of the documentation building process.
819    
820    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
821        --match-limit and --recursion-limit options (added for 8.11). In
822        particular, this made one of the standard tests fail. (The integer value
823        went into the wrong half of a long int.)
824    
825    3.  If the --colour option was given to pcregrep with -v (invert match), it
826        did strange things, either producing crazy output, or crashing. It should,
827        of course, ignore a request for colour when reporting lines that do not
828        match.
829    
830    4.  Another pcregrep bug caused similar problems if --colour was specified with
831        -M (multiline) and the pattern match finished with a line ending.
832    
833    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
834        matched in multiline mode, the following line was shown as part of the
835        match. This seems wrong, so I have changed it.
836    
837    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
838        the check for further matches in the same line (so they could be coloured)
839        to overrun the end of the current line. If another match was found, it was
840        incorrectly shown (and then shown again when found in the next line).
841    
842    7.  If pcregrep was compiled under Windows, there was a reference to the
843        function pcregrep_exit() before it was defined. I am assuming this was
844        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
845        reported by a user. I've moved the definition above the reference.
846    
847    
848    Version 8.11 10-Dec-2010
849    ------------------------
850    
851    1.  (*THEN) was not working properly if there were untried alternatives prior
852        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
853        backtracked to try for "b" instead of moving to the next alternative branch
854        at the same level (in this case, to look for "c"). The Perl documentation
855        is clear that when (*THEN) is backtracked onto, it goes to the "next
856        alternative in the innermost enclosing group".
857    
858    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
859        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
860        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
861        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
862        (*THEN).
863    
864    3.  If \s appeared in a character class, it removed the VT character from
865        the class, even if it had been included by some previous item, for example
866        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
867        of \s, but is part of the POSIX "space" class.)
868    
869    4.  A partial match never returns an empty string (because you can always
870        match an empty string at the end of the subject); however the checking for
871        an empty string was starting at the "start of match" point. This has been
872        changed to the "earliest inspected character" point, because the returned
873        data for a partial match starts at this character. This means that, for
874        example, /(?<=abc)def/ gives a partial match for the subject "abc"
875        (previously it gave "no match").
876    
877    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
878        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
879        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
880        has an implication that the given string is incomplete (because a partial
881        match is preferred over a full match). For this reason, these items now
882        give a partial match in this situation. [Aside: previously, the one case
883        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
884        match rather than a full match, which was wrong by the old rules, but is
885        now correct.]
886    
887    6.  There was a bug in the handling of #-introduced comments, recognized when
888        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
889        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
890        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
891        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
892        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
893        places in pcre_compile().
894    
895    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
896        comments when looking ahead for named forward references to subpatterns,
897        the only newline sequence it recognized was NL. It now handles newlines
898        according to the set newline convention.
899    
900    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
901        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
902        cater for a lack of strerror(). These oversights have been fixed.
903    
904    9.  Added --match-limit and --recursion-limit to pcregrep.
905    
906    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
907    
908    11. When the -o option was used, pcregrep was setting a return code of 1, even
909        when matches were found, and --line-buffered was not being honoured.
910    
911    12. Added an optional parentheses number to the -o and --only-matching options
912        of pcregrep.
913    
914    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
915        can match an empty string. The code to do it in pcretest and pcredemo
916        needed fixing:
917    
918        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
919            only one byte after an empty string match just before CRLF (this case
920            just got forgotten; "any" and "anycrlf" were OK).
921    
922        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
923            mode when an empty string match preceded an ASCII character followed by
924            a non-ASCII character. (The code for advancing by one character rather
925            than one byte was nonsense.)
926    
927        (c) The pcredemo.c sample program did not have any code at all to handle
928            the cases when CRLF is a valid newline sequence.
929    
930    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
931        as a starting offset was within the subject string. There is now a new
932        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
933        negative or greater than the length of the string. In order to test this,
934        pcretest is extended to allow the setting of negative starting offsets.
935    
936    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
937        starting offset points to the beginning of a UTF-8 character was
938        unnecessarily clumsy. I tidied it up.
939    
940    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
941        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
942    
943    17. Nobody had reported that the --include_dir option, which was added in
944        release 7.7 should have been called --include-dir (hyphen, not underscore)
945        for compatibility with GNU grep. I have changed it to --include-dir, but
946        left --include_dir as an undocumented synonym, and the same for
947        --exclude-dir, though that is not available in GNU grep, at least as of
948        release 2.5.4.
949    
950    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
951        characters from a string of bytes) have been redefined so as not to use
952        loops, in order to improve performance in some environments. At the same
953        time, I abstracted some of the common code into auxiliary macros to save
954        repetition (this should not affect the compiled code).
955    
956    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
957        compile-time error is now given if \c is not followed by an ASCII
958        character, that is, a byte less than 128. (In EBCDIC mode, the code is
959        different, and any byte value is allowed.)
960    
961    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
962        START_OPTIMIZE option, which is now allowed at compile time - but just
963        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
964        to pcregrep and other applications that have no direct access to PCRE
965        options. The new /Y option in pcretest sets this option when calling
966        pcre_compile().
967    
968    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
969        back references. Groups containing recursive back references were forced to
970        be atomic by that change, but in the case of named groups, the amount of
971        memory required was incorrectly computed, leading to "Failed: internal
972        error: code overflow". This has been fixed.
973    
974    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
975        pcretest.c, to avoid build problems in some Borland environments.
976    
977    
978    Version 8.10 25-Jun-2010
979  ------------------------  ------------------------
980    
981  1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and  1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and

Legend:
Removed from v.545  
changed lines
  Added in v.1050

  ViewVC Help
Powered by ViewVC 1.1.5