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

Diff of /code/trunk/ChangeLog

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

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

Legend:
Removed from v.335  
changed lines
  Added in v.1009

  ViewVC Help
Powered by ViewVC 1.1.5