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1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 7.1 12-Mar-07  Version 8.31 20-June-2012
5    -------------------------
6    
7    1.  Fixing a wrong JIT test case and some compiler warnings.
8    
9    2.  Removed a bashism from the RunTest script.
10    
11    3.  Add a cast to pcre_exec.c to fix the warning "unary minus operator applied
12        to unsigned type, result still unsigned" that was given by an MS compiler
13        on encountering the code "-sizeof(xxx)".
14    
15    4.  Partial matching support is added to the JIT compiler.
16    
17    5.  Fixed several bugs concerned with partial matching of items that consist
18        of more than one character:
19    
20        (a) /^(..)\1/ did not partially match "aba" because checking references was
21            done on an "all or nothing" basis. This also applied to repeated
22            references.
23    
24        (b) \R did not give a hard partial match if \r was found at the end of the
25            subject.
26    
27        (c) \X did not give a hard partial match after matching one or more
28            characters at the end of the subject.
29    
30        (d) When newline was set to CRLF, a pattern such as /a$/ did not recognize
31            a partial match for the string "\r".
32    
33        (e) When newline was set to CRLF, the metacharacter "." did not recognize
34            a partial match for a CR character at the end of the subject string.
35    
36    6.  If JIT is requested using /S++ or -s++ (instead of just /S+ or -s+) when
37        running pcretest, the text "(JIT)" added to the output whenever JIT is
38        actually used to run the match.
39    
40    7.  Individual JIT compile options can be set in pcretest by following -s+[+]
41        or /S+[+] with a digit between 1 and 7.
42    
43    8.  OP_NOT now supports any UTF character not just single-byte ones.
44    
45    9.  (*MARK) control verb is now supported by the JIT compiler.
46    
47    10. The command "./RunTest list" lists the available tests without actually
48        running any of them. (Because I keep forgetting what they all are.)
49    
50    11. Add PCRE_INFO_MAXLOOKBEHIND.
51    
52    12. Applied a (slightly modified) user-supplied patch that improves performance
53        when the heap is used for recursion (compiled with --disable-stack-for-
54        recursion). Instead of malloc and free for each heap frame each time a
55        logical recursion happens, frames are retained on a chain and re-used where
56        possible. This sometimes gives as much as 30% improvement.
57    
58    13. As documented, (*COMMIT) is now confined to within a recursive subpattern
59        call.
60    
61    14. As documented, (*COMMIT) is now confined to within a positive assertion.
62    
63    15. It is now possible to link pcretest with libedit as an alternative to
64        libreadline.
65    
66    16. (*COMMIT) control verb is now supported by the JIT compiler.
67    
68    17. The Unicode data tables have been updated to Unicode 6.1.0.
69    
70    18. Added --file-list option to pcregrep.
71    
72    19. Added binary file support to pcregrep, including the -a, --binary-files,
73        -I, and --text options.
74    
75    20. The madvise function is renamed for posix_madvise for QNX compatibility
76        reasons. Fixed by Giuseppe D'Angelo.
77    
78    21. Fixed a bug for backward assertions with REVERSE 0 in the JIT compiler.
79    
80    22. Changed the option for creating symbolic links for 16-bit man pages from
81        -s to -sf so that re-installing does not cause issues.
82    
83    23. Support PCRE_NO_START_OPTIMIZE in JIT as (*MARK) support requires it.
84    
85    24. Fixed a very old bug in pcretest that caused errors with restarted DFA
86        matches in certain environments (the workspace was not being correctly
87        retained). Also added to pcre_dfa_exec() a simple plausibility check on
88        some of the workspace data at the beginning of a restart.
89    
90    25. \s*\R was auto-possessifying the \s* when it should not, whereas \S*\R
91        was not doing so when it should - probably a typo introduced by SVN 528
92        (change 8.10/14).
93    
94    26. When PCRE_UCP was not set, \w+\x{c4} was incorrectly auto-possessifying the
95        \w+ when the character tables indicated that \x{c4} was a word character.
96        There were several related cases, all because the tests for doing a table
97        lookup were testing for characters less than 127 instead of 255.
98    
99    27. If a pattern contains capturing parentheses that are not used in a match,
100        their slots in the ovector are set to -1. For those that are higher than
101        any matched groups, this happens at the end of processing. In the case when
102        there were back references that the ovector was too small to contain
103        (causing temporary malloc'd memory to be used during matching), and the
104        highest capturing number was not used, memory off the end of the ovector
105        was incorrectly being set to -1. (It was using the size of the temporary
106        memory instead of the true size.)
107    
108    28. To catch bugs like 27 using valgrind, when pcretest is asked to specify an
109        ovector size, it uses memory at the end of the block that it has got.
110    
111    29. Check for an overlong MARK name and give an error at compile time. The
112        limit is 255 for the 8-bit library and 65535 for the 16-bit library.
113    
114    30. JIT compiler update.
115    
116    31. JIT is now supported on jailbroken iOS devices. Thanks for Ruiger
117        Rill for the patch.
118    
119    32. Put spaces around SLJIT_PRINT_D in the JIT compiler. Required by CXX11.
120    
121    33. Variable renamings in the PCRE-JIT compiler. No functionality change.
122    
123    34. Fixed typos in pcregrep: in two places there was SUPPORT_LIBZ2 instead of
124        SUPPORT_LIBBZ2. This caused a build problem when bzip2 but not gzip (zlib)
125        was enabled.
126    
127    35. Improve JIT code generation for greedy plus quantifier.
128    
129    36. When /((?:a?)*)*c/ or /((?>a?)*)*c/ was matched against "aac", it set group
130        1 to "aa" instead of to an empty string. The bug affected repeated groups
131        that could potentially match an empty string.
132    
133    37. Optimizing single character iterators in JIT.
134    
135    38. Wide characters specified with \uxxxx in JavaScript mode are now subject to
136        the same checks as \x{...} characters in non-JavaScript mode. Specifically,
137        codepoints that are too big for the mode are faulted, and in a UTF mode,
138        disallowed codepoints are also faulted.
139    
140    39. If PCRE was compiled with UTF support, in three places in the DFA
141        matcher there was code that should only have been obeyed in UTF mode, but
142        was being obeyed unconditionally. In 8-bit mode this could cause incorrect
143        processing when bytes with values greater than 127 were present. In 16-bit
144        mode the bug would be provoked by values in the range 0xfc00 to 0xdc00. In
145        both cases the values are those that cannot be the first data item in a UTF
146        character. The three items that might have provoked this were recursions,
147        possessively repeated groups, and atomic groups.
148    
149    40. Ensure that libpcre is explicitly listed in the link commands for pcretest
150        and pcregrep, because some OS require shared objects to be explicitly
151        passed to ld, causing the link step to fail if they are not.
152    
153    
154    Version 8.30 04-February-2012
155    -----------------------------
156    
157    1.  Renamed "isnumber" as "is_a_number" because in some Mac environments this
158        name is defined in ctype.h.
159    
160    2.  Fixed a bug in fixed-length calculation for lookbehinds that would show up
161        only in quite long subpatterns.
162    
163    3.  Removed the function pcre_info(), which has been obsolete and deprecated
164        since it was replaced by pcre_fullinfo() in February 2000.
165    
166    4.  For a non-anchored pattern, if (*SKIP) was given with a name that did not
167        match a (*MARK), and the match failed at the start of the subject, a
168        reference to memory before the start of the subject could occur. This bug
169        was introduced by fix 17 of release 8.21.
170    
171    5.  A reference to an unset group with zero minimum repetition was giving
172        totally wrong answers (in non-JavaScript-compatibility mode). For example,
173        /(another)?(\1?)test/ matched against "hello world test". This bug was
174        introduced in release 8.13.
175    
176    6.  Add support for 16-bit character strings (a large amount of work involving
177        many changes and refactorings).
178    
179    7.  RunGrepTest failed on msys because \r\n was replaced by whitespace when the
180        command "pattern=`printf 'xxx\r\njkl'`" was run. The pattern is now taken
181        from a file.
182    
183    8.  Ovector size of 2 is also supported by JIT based pcre_exec (the ovector size
184        rounding is not applied in this particular case).
185    
186    9.  The invalid Unicode surrogate codepoints U+D800 to U+DFFF are now rejected
187        if they appear, or are escaped, in patterns.
188    
189    10. Get rid of a number of -Wunused-but-set-variable warnings.
190    
191    11. The pattern /(?=(*:x))(q|)/ matches an empty string, and returns the mark
192        "x". The similar pattern /(?=(*:x))((*:y)q|)/ did not return a mark at all.
193        Oddly, Perl behaves the same way. PCRE has been fixed so that this pattern
194        also returns the mark "x". This bug applied to capturing parentheses,
195        non-capturing parentheses, and atomic parentheses. It also applied to some
196        assertions.
197    
198    12. Stephen Kelly's patch to CMakeLists.txt allows it to parse the version
199        information out of configure.ac instead of relying on pcre.h.generic, which
200        is not stored in the repository.
201    
202    13. Applied Dmitry V. Levin's patch for a more portable method for linking with
203        -lreadline.
204    
205    14. ZH added PCRE_CONFIG_JITTARGET; added its output to pcretest -C.
206    
207    15. Applied Graycode's patch to put the top-level frame on the stack rather
208        than the heap when not using the stack for recursion. This gives a
209        performance improvement in many cases when recursion is not deep.
210    
211    16. Experimental code added to "pcretest -C" to output the stack frame size.
212    
213    
214    Version 8.21 12-Dec-2011
215    ------------------------
216    
217    1.  Updating the JIT compiler.
218    
219    2.  JIT compiler now supports OP_NCREF, OP_RREF and OP_NRREF. New test cases
220        are added as well.
221    
222    3.  Fix cache-flush issue on PowerPC (It is still an experimental JIT port).
223        PCRE_EXTRA_TABLES is not suported by JIT, and should be checked before
224        calling _pcre_jit_exec. Some extra comments are added.
225    
226    4.  (*MARK) settings inside atomic groups that do not contain any capturing
227        parentheses, for example, (?>a(*:m)), were not being passed out. This bug
228        was introduced by change 18 for 8.20.
229    
230    5.  Supporting of \x, \U and \u in JavaScript compatibility mode based on the
231        ECMA-262 standard.
232    
233    6.  Lookbehinds such as (?<=a{2}b) that contained a fixed repetition were
234        erroneously being rejected as "not fixed length" if PCRE_CASELESS was set.
235        This bug was probably introduced by change 9 of 8.13.
236    
237    7.  While fixing 6 above, I noticed that a number of other items were being
238        incorrectly rejected as "not fixed length". This arose partly because newer
239        opcodes had not been added to the fixed-length checking code. I have (a)
240        corrected the bug and added tests for these items, and (b) arranged for an
241        error to occur if an unknown opcode is encountered while checking for fixed
242        length instead of just assuming "not fixed length". The items that were
243        rejected were: (*ACCEPT), (*COMMIT), (*FAIL), (*MARK), (*PRUNE), (*SKIP),
244        (*THEN), \h, \H, \v, \V, and single character negative classes with fixed
245        repetitions, e.g. [^a]{3}, with and without PCRE_CASELESS.
246    
247    8.  A possessively repeated conditional subpattern such as (?(?=c)c|d)++ was
248        being incorrectly compiled and would have given unpredicatble results.
249    
250    9.  A possessively repeated subpattern with minimum repeat count greater than
251        one behaved incorrectly. For example, (A){2,}+ behaved as if it was
252        (A)(A)++ which meant that, after a subsequent mismatch, backtracking into
253        the first (A) could occur when it should not.
254    
255    10. Add a cast and remove a redundant test from the code.
256    
257    11. JIT should use pcre_malloc/pcre_free for allocation.
258    
259    12. Updated pcre-config so that it no longer shows -L/usr/lib, which seems
260        best practice nowadays, and helps with cross-compiling. (If the exec_prefix
261        is anything other than /usr, -L is still shown).
262    
263    13. In non-UTF-8 mode, \C is now supported in lookbehinds and DFA matching.
264    
265    14. Perl does not support \N without a following name in a [] class; PCRE now
266        also gives an error.
267    
268    15. If a forward reference was repeated with an upper limit of around 2000,
269        it caused the error "internal error: overran compiling workspace". The
270        maximum number of forward references (including repeats) was limited by the
271        internal workspace, and dependent on the LINK_SIZE. The code has been
272        rewritten so that the workspace expands (via pcre_malloc) if necessary, and
273        the default depends on LINK_SIZE. There is a new upper limit (for safety)
274        of around 200,000 forward references. While doing this, I also speeded up
275        the filling in of repeated forward references.
276    
277    16. A repeated forward reference in a pattern such as (a)(?2){2}(.) was
278        incorrectly expecting the subject to contain another "a" after the start.
279    
280    17. When (*SKIP:name) is activated without a corresponding (*MARK:name) earlier
281        in the match, the SKIP should be ignored. This was not happening; instead
282        the SKIP was being treated as NOMATCH. For patterns such as
283        /A(*MARK:A)A+(*SKIP:B)Z|AAC/ this meant that the AAC branch was never
284        tested.
285    
286    18. The behaviour of (*MARK), (*PRUNE), and (*THEN) has been reworked and is
287        now much more compatible with Perl, in particular in cases where the result
288        is a non-match for a non-anchored pattern. For example, if
289        /b(*:m)f|a(*:n)w/ is matched against "abc", the non-match returns the name
290        "m", where previously it did not return a name. A side effect of this
291        change is that for partial matches, the last encountered mark name is
292        returned, as for non matches. A number of tests that were previously not
293        Perl-compatible have been moved into the Perl-compatible test files. The
294        refactoring has had the pleasing side effect of removing one argument from
295        the match() function, thus reducing its stack requirements.
296    
297    19. If the /S+ option was used in pcretest to study a pattern using JIT,
298        subsequent uses of /S (without +) incorrectly behaved like /S+.
299    
300    21. Retrieve executable code size support for the JIT compiler and fixing
301        some warnings.
302    
303    22. A caseless match of a UTF-8 character whose other case uses fewer bytes did
304        not work when the shorter character appeared right at the end of the
305        subject string.
306    
307    23. Added some (int) casts to non-JIT modules to reduce warnings on 64-bit
308        systems.
309    
310    24. Added PCRE_INFO_JITSIZE to pass on the value from (21) above, and also
311        output it when the /M option is used in pcretest.
312    
313    25. The CheckMan script was not being included in the distribution. Also, added
314        an explicit "perl" to run Perl scripts from the PrepareRelease script
315        because this is reportedly needed in Windows.
316    
317    26. If study data was being save in a file and studying had not found a set of
318        "starts with" bytes for the pattern, the data written to the file (though
319        never used) was taken from uninitialized memory and so caused valgrind to
320        complain.
321    
322    27. Updated RunTest.bat as provided by Sheri Pierce.
323    
324    28. Fixed a possible uninitialized memory bug in pcre_jit_compile.c.
325    
326    29. Computation of memory usage for the table of capturing group names was
327        giving an unnecessarily large value.
328    
329    
330    Version 8.20 21-Oct-2011
331    ------------------------
332    
333    1.  Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
334        a POSIX class. After further experiments with Perl, which convinced me that
335        Perl has bugs and confusions, a closing square bracket is no longer allowed
336        in a POSIX name. This bug also affected patterns with classes that started
337        with full stops.
338    
339    2.  If a pattern such as /(a)b|ac/ is matched against "ac", there is no
340        captured substring, but while checking the failing first alternative,
341        substring 1 is temporarily captured. If the output vector supplied to
342        pcre_exec() was not big enough for this capture, the yield of the function
343        was still zero ("insufficient space for captured substrings"). This cannot
344        be totally fixed without adding another stack variable, which seems a lot
345        of expense for a edge case. However, I have improved the situation in cases
346        such as /(a)(b)x|abc/ matched against "abc", where the return code
347        indicates that fewer than the maximum number of slots in the ovector have
348        been set.
349    
350    3.  Related to (2) above: when there are more back references in a pattern than
351        slots in the output vector, pcre_exec() uses temporary memory during
352        matching, and copies in the captures as far as possible afterwards. It was
353        using the entire output vector, but this conflicts with the specification
354        that only 2/3 is used for passing back captured substrings. Now it uses
355        only the first 2/3, for compatibility. This is, of course, another edge
356        case.
357    
358    4.  Zoltan Herczeg's just-in-time compiler support has been integrated into the
359        main code base, and can be used by building with --enable-jit. When this is
360        done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
361        runtime --no-jit option is given.
362    
363    5.  When the number of matches in a pcre_dfa_exec() run exactly filled the
364        ovector, the return from the function was zero, implying that there were
365        other matches that did not fit. The correct "exactly full" value is now
366        returned.
367    
368    6.  If a subpattern that was called recursively or as a subroutine contained
369        (*PRUNE) or any other control that caused it to give a non-standard return,
370        invalid errors such as "Error -26 (nested recursion at the same subject
371        position)" or even infinite loops could occur.
372    
373    7.  If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
374        computing the minimum length on reaching *ACCEPT, and so ended up with the
375        wrong value of 1 rather than 0. Further investigation indicates that
376        computing a minimum subject length in the presence of *ACCEPT is difficult
377        (think back references, subroutine calls), and so I have changed the code
378        so that no minimum is registered for a pattern that contains *ACCEPT.
379    
380    8.  If (*THEN) was present in the first (true) branch of a conditional group,
381        it was not handled as intended. [But see 16 below.]
382    
383    9.  Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
384        Sheri Pierce.
385    
386    10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
387        the first byte in a match must be "a".
388    
389    11. Change 17 for 8.13 increased the recursion depth for patterns like
390        /a(?:.)*?a/ drastically. I've improved things by remembering whether a
391        pattern contains any instances of (*THEN). If it does not, the old
392        optimizations are restored. It would be nice to do this on a per-group
393        basis, but at the moment that is not feasible.
394    
395    12. In some environments, the output of pcretest -C is CRLF terminated. This
396        broke RunTest's code that checks for the link size. A single white space
397        character after the value is now allowed for.
398    
399    13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
400        For "fr", it uses the Windows-specific input and output files.
401    
402    14. If (*THEN) appeared in a group that was called recursively or as a
403        subroutine, it did not work as intended. [But see next item.]
404    
405    15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
406        pattern fragments (but not containing any | characters). If A and B are
407        matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
408        was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
409        D. In other words, Perl considers parentheses that do not contain any |
410        characters to be part of a surrounding alternative, whereas PCRE was
411        treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
412        differently. PCRE now behaves in the same way as Perl, except in the case
413        of subroutine/recursion calls such as (?1) which have in any case always
414        been different (but PCRE had them first :-).
415    
416    16. Related to 15 above: Perl does not treat the | in a conditional group as
417        creating alternatives. Such a group is treated in the same way as an
418        ordinary group without any | characters when processing (*THEN). PCRE has
419        been changed to match Perl's behaviour.
420    
421    17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
422        RunGrepTest script failed.
423    
424    18. Change 22 for version 13 caused atomic groups to use more stack. This is
425        inevitable for groups that contain captures, but it can lead to a lot of
426        stack use in large patterns. The old behaviour has been restored for atomic
427        groups that do not contain any capturing parentheses.
428    
429    19. If the PCRE_NO_START_OPTIMIZE option was set for pcre_compile(), it did not
430        suppress the check for a minimum subject length at run time. (If it was
431        given to pcre_exec() or pcre_dfa_exec() it did work.)
432    
433    20. Fixed an ASCII-dependent infelicity in pcretest that would have made it
434        fail to work when decoding hex characters in data strings in EBCDIC
435        environments.
436    
437    21. It appears that in at least one Mac OS environment, the isxdigit() function
438        is implemented as a macro that evaluates to its argument more than once,
439        contravening the C 90 Standard (I haven't checked a later standard). There
440        was an instance in pcretest which caused it to go wrong when processing
441        \x{...} escapes in subject strings. The has been rewritten to avoid using
442        things like p++ in the argument of isxdigit().
443    
444    
445    Version 8.13 16-Aug-2011
446    ------------------------
447    
448    1.  The Unicode data tables have been updated to Unicode 6.0.0.
449    
450    2.  Two minor typos in pcre_internal.h have been fixed.
451    
452    3.  Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
453        pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
454        in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
455    
456    4.  There were a number of related bugs in the code for matching backrefences
457        caselessly in UTF-8 mode when codes for the characters concerned were
458        different numbers of bytes. For example, U+023A and U+2C65 are an upper
459        and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
460        (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
461        code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
462        2-byte code at the end of the subject (it thought there wasn't enough data
463        left).
464    
465    5.  Comprehensive information about what went wrong is now returned by
466        pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
467        as the output vector has at least 2 elements. The offset of the start of
468        the failing character and a reason code are placed in the vector.
469    
470    6.  When the UTF-8 string check fails for pcre_compile(), the offset that is
471        now returned is for the first byte of the failing character, instead of the
472        last byte inspected. This is an incompatible change, but I hope it is small
473        enough not to be a problem. It makes the returned offset consistent with
474        pcre_exec() and pcre_dfa_exec().
475    
476    7.  pcretest now gives a text phrase as well as the error number when
477        pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
478        failure, the offset and reason code are output.
479    
480    8.  When \R was used with a maximizing quantifier it failed to skip backwards
481        over a \r\n pair if the subsequent match failed. Instead, it just skipped
482        back over a single character (\n). This seems wrong (because it treated the
483        two characters as a single entity when going forwards), conflicts with the
484        documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
485        behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
486        has been changed.
487    
488    9.  Some internal refactoring has changed the processing so that the handling
489        of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
490        time (the PCRE_DOTALL option was changed this way some time ago: version
491        7.7 change 16). This has made it possible to abolish the OP_OPT op code,
492        which was always a bit of a fudge. It also means that there is one less
493        argument for the match() function, which reduces its stack requirements
494        slightly. This change also fixes an incompatibility with Perl: the pattern
495        (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
496    
497    10. More internal refactoring has drastically reduced the number of recursive
498        calls to match() for possessively repeated groups such as (abc)++ when
499        using pcre_exec().
500    
501    11. While implementing 10, a number of bugs in the handling of groups were
502        discovered and fixed:
503    
504        (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
505        (a|)*(?1) gave a compile-time internal error.
506        ((a|)+)+  did not notice that the outer group could match an empty string.
507        (^a|^)+   was not marked as anchored.
508        (.*a|.*)+ was not marked as matching at start or after a newline.
509    
510    12. Yet more internal refactoring has removed another argument from the match()
511        function. Special calls to this function are now indicated by setting a
512        value in a variable in the "match data" data block.
513    
514    13. Be more explicit in pcre_study() instead of relying on "default" for
515        opcodes that mean there is no starting character; this means that when new
516        ones are added and accidentally left out of pcre_study(), testing should
517        pick them up.
518    
519    14. The -s option of pcretest has been documented for ages as being an old
520        synonym of -m (show memory usage). I have changed it to mean "force study
521        for every regex", that is, assume /S for every regex. This is similar to -i
522        and -d etc. It's slightly incompatible, but I'm hoping nobody is still
523        using it. It makes it easier to run collections of tests with and without
524        study enabled, and thereby test pcre_study() more easily. All the standard
525        tests are now run with and without -s (but some patterns can be marked as
526        "never study" - see 20 below).
527    
528    15. When (*ACCEPT) was used in a subpattern that was called recursively, the
529        restoration of the capturing data to the outer values was not happening
530        correctly.
531    
532    16. If a recursively called subpattern ended with (*ACCEPT) and matched an
533        empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
534        pattern had matched an empty string, and so incorrectly returned a no
535        match.
536    
537    17. There was optimizing code for the last branch of non-capturing parentheses,
538        and also for the obeyed branch of a conditional subexpression, which used
539        tail recursion to cut down on stack usage. Unfortunately, now that there is
540        the possibility of (*THEN) occurring in these branches, tail recursion is
541        no longer possible because the return has to be checked for (*THEN). These
542        two optimizations have therefore been removed. [But see 8.20/11 above.]
543    
544    18. If a pattern containing \R was studied, it was assumed that \R always
545        matched two bytes, thus causing the minimum subject length to be
546        incorrectly computed because \R can also match just one byte.
547    
548    19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
549        was incorrectly computed.
550    
551    20. If /S is present twice on a test pattern in pcretest input, it now
552        *disables* studying, thereby overriding the use of -s on the command line
553        (see 14 above). This is necessary for one or two tests to keep the output
554        identical in both cases.
555    
556    21. When (*ACCEPT) was used in an assertion that matched an empty string and
557        PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
558    
559    22. When an atomic group that contained a capturing parenthesis was
560        successfully matched, but the branch in which it appeared failed, the
561        capturing was not being forgotten if a higher numbered group was later
562        captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
563        group 1 to "a", when in fact it should be unset. This applied to multi-
564        branched capturing and non-capturing groups, repeated or not, and also to
565        positive assertions (capturing in negative assertions does not happen
566        in PCRE) and also to nested atomic groups.
567    
568    23. Add the ++ qualifier feature to pcretest, to show the remainder of the
569        subject after a captured substring, to make it easier to tell which of a
570        number of identical substrings has been captured.
571    
572    24. The way atomic groups are processed by pcre_exec() has been changed so that
573        if they are repeated, backtracking one repetition now resets captured
574        values correctly. For example, if ((?>(a+)b)+aabab) is matched against
575        "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
576        "aaa". Previously, it would have been "a". As part of this code
577        refactoring, the way recursive calls are handled has also been changed.
578    
579    25. If an assertion condition captured any substrings, they were not passed
580        back unless some other capturing happened later. For example, if
581        (?(?=(a))a) was matched against "a", no capturing was returned.
582    
583    26. When studying a pattern that contained subroutine calls or assertions,
584        the code for finding the minimum length of a possible match was handling
585        direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
586        group 1 called group 2 while simultaneously a separate group 2 called group
587        1). A stack overflow occurred in this case. I have fixed this by limiting
588        the recursion depth to 10.
589    
590    27. Updated RunTest.bat in the distribution to the version supplied by Tom
591        Fortmann. This supports explicit test numbers on the command line, and has
592        argument validation and error reporting.
593    
594    28. An instance of \X with an unlimited repeat could fail if at any point the
595        first character it looked at was a mark character.
596    
597    29. Some minor code refactoring concerning Unicode properties and scripts
598        should reduce the stack requirement of match() slightly.
599    
600    30. Added the '=' option to pcretest to check the setting of unused capturing
601        slots at the end of the pattern, which are documented as being -1, but are
602        not included in the return count.
603    
604    31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
605        compiled something random. Now it gives a compile-time error (as does
606        Perl).
607    
608    32. A *MARK encountered during the processing of a positive assertion is now
609        recorded and passed back (compatible with Perl).
610    
611    33. If --only-matching or --colour was set on a pcregrep call whose pattern
612        had alternative anchored branches, the search for a second match in a line
613        was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
614        matched the line "0102" twice. The same bug affected patterns that started
615        with a backwards assertion. For example /\b01|\b02/ also matched "0102"
616        twice.
617    
618    34. Previously, PCRE did not allow quantification of assertions. However, Perl
619        does, and because of capturing effects, quantifying parenthesized
620        assertions may at times be useful. Quantifiers are now allowed for
621        parenthesized assertions.
622    
623    35. A minor code tidy in pcre_compile() when checking options for \R usage.
624    
625    36. \g was being checked for fancy things in a character class, when it should
626        just be a literal "g".
627    
628    37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
629        appearance of a nested POSIX class supersedes an apparent external class.
630        For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
631        unescaped square brackets may also appear as part of class names. For
632        example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
633        more like Perl. (But see 8.20/1 above.)
634    
635    38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
636        was because it thought it was \N{name}, which is not supported).
637    
638    39. Add minix to OS list not supporting the -S option in pcretest.
639    
640    40. PCRE tries to detect cases of infinite recursion at compile time, but it
641        cannot analyze patterns in sufficient detail to catch mutual recursions
642        such as ((?1))((?2)). There is now a runtime test that gives an error if a
643        subgroup is called recursively as a subpattern for a second time at the
644        same position in the subject string. In previous releases this might have
645        been caught by the recursion limit, or it might have run out of stack.
646    
647    41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
648        happen only once. PCRE was, however incorrectly giving a compile time error
649        "recursive call could loop indefinitely" because it cannot analyze the
650        pattern in sufficient detail. The compile time test no longer happens when
651        PCRE is compiling a conditional subpattern, but actual runaway loops are
652        now caught at runtime (see 40 above).
653    
654    42. It seems that Perl allows any characters other than a closing parenthesis
655        to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
656        has been changed to be the same.
657    
658    43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
659        as not to get warnings when autogen.sh is called. Also changed
660        AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
661    
662    44. To help people who use pcregrep to scan files containing exceedingly long
663        lines, the following changes have been made:
664    
665        (a) The default value of the buffer size parameter has been increased from
666            8K to 20K. (The actual buffer used is three times this size.)
667    
668        (b) The default can be changed by ./configure --with-pcregrep-bufsize when
669            PCRE is built.
670    
671        (c) A --buffer-size=n option has been added to pcregrep, to allow the size
672            to be set at run time.
673    
674        (d) Numerical values in pcregrep options can be followed by K or M, for
675            example --buffer-size=50K.
676    
677        (e) If a line being scanned overflows pcregrep's buffer, an error is now
678            given and the return code is set to 2.
679    
680    45. Add a pointer to the latest mark to the callout data block.
681    
682    46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
683        partial match of an empty string instead of no match. This was specific to
684        the use of ".".
685    
686    47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
687        complete match instead of a partial match. This bug was dependent on both
688        the PCRE_UTF8 and PCRE_DOTALL options being set.
689    
690    48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
691        starting byte set, because \b was not being ignored.
692    
693    
694    Version 8.12 15-Jan-2011
695    ------------------------
696    
697    1.  Fixed some typos in the markup of the man pages, and wrote a script that
698        checks for such things as part of the documentation building process.
699    
700    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
701        --match-limit and --recursion-limit options (added for 8.11). In
702        particular, this made one of the standard tests fail. (The integer value
703        went into the wrong half of a long int.)
704    
705    3.  If the --colour option was given to pcregrep with -v (invert match), it
706        did strange things, either producing crazy output, or crashing. It should,
707        of course, ignore a request for colour when reporting lines that do not
708        match.
709    
710    4.  Another pcregrep bug caused similar problems if --colour was specified with
711        -M (multiline) and the pattern match finished with a line ending.
712    
713    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
714        matched in multiline mode, the following line was shown as part of the
715        match. This seems wrong, so I have changed it.
716    
717    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
718        the check for further matches in the same line (so they could be coloured)
719        to overrun the end of the current line. If another match was found, it was
720        incorrectly shown (and then shown again when found in the next line).
721    
722    7.  If pcregrep was compiled under Windows, there was a reference to the
723        function pcregrep_exit() before it was defined. I am assuming this was
724        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
725        reported by a user. I've moved the definition above the reference.
726    
727    
728    Version 8.11 10-Dec-2010
729    ------------------------
730    
731    1.  (*THEN) was not working properly if there were untried alternatives prior
732        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
733        backtracked to try for "b" instead of moving to the next alternative branch
734        at the same level (in this case, to look for "c"). The Perl documentation
735        is clear that when (*THEN) is backtracked onto, it goes to the "next
736        alternative in the innermost enclosing group".
737    
738    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
739        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
740        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
741        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
742        (*THEN).
743    
744    3.  If \s appeared in a character class, it removed the VT character from
745        the class, even if it had been included by some previous item, for example
746        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
747        of \s, but is part of the POSIX "space" class.)
748    
749    4.  A partial match never returns an empty string (because you can always
750        match an empty string at the end of the subject); however the checking for
751        an empty string was starting at the "start of match" point. This has been
752        changed to the "earliest inspected character" point, because the returned
753        data for a partial match starts at this character. This means that, for
754        example, /(?<=abc)def/ gives a partial match for the subject "abc"
755        (previously it gave "no match").
756    
757    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
758        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
759        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
760        has an implication that the given string is incomplete (because a partial
761        match is preferred over a full match). For this reason, these items now
762        give a partial match in this situation. [Aside: previously, the one case
763        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
764        match rather than a full match, which was wrong by the old rules, but is
765        now correct.]
766    
767    6.  There was a bug in the handling of #-introduced comments, recognized when
768        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
769        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
770        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
771        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
772        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
773        places in pcre_compile().
774    
775    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
776        comments when looking ahead for named forward references to subpatterns,
777        the only newline sequence it recognized was NL. It now handles newlines
778        according to the set newline convention.
779    
780    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
781        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
782        cater for a lack of strerror(). These oversights have been fixed.
783    
784    9.  Added --match-limit and --recursion-limit to pcregrep.
785    
786    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
787    
788    11. When the -o option was used, pcregrep was setting a return code of 1, even
789        when matches were found, and --line-buffered was not being honoured.
790    
791    12. Added an optional parentheses number to the -o and --only-matching options
792        of pcregrep.
793    
794    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
795        can match an empty string. The code to do it in pcretest and pcredemo
796        needed fixing:
797    
798        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
799            only one byte after an empty string match just before CRLF (this case
800            just got forgotten; "any" and "anycrlf" were OK).
801    
802        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
803            mode when an empty string match preceded an ASCII character followed by
804            a non-ASCII character. (The code for advancing by one character rather
805            than one byte was nonsense.)
806    
807        (c) The pcredemo.c sample program did not have any code at all to handle
808            the cases when CRLF is a valid newline sequence.
809    
810    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
811        as a starting offset was within the subject string. There is now a new
812        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
813        negative or greater than the length of the string. In order to test this,
814        pcretest is extended to allow the setting of negative starting offsets.
815    
816    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
817        starting offset points to the beginning of a UTF-8 character was
818        unnecessarily clumsy. I tidied it up.
819    
820    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
821        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
822    
823    17. Nobody had reported that the --include_dir option, which was added in
824        release 7.7 should have been called --include-dir (hyphen, not underscore)
825        for compatibility with GNU grep. I have changed it to --include-dir, but
826        left --include_dir as an undocumented synonym, and the same for
827        --exclude-dir, though that is not available in GNU grep, at least as of
828        release 2.5.4.
829    
830    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
831        characters from a string of bytes) have been redefined so as not to use
832        loops, in order to improve performance in some environments. At the same
833        time, I abstracted some of the common code into auxiliary macros to save
834        repetition (this should not affect the compiled code).
835    
836    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
837        compile-time error is now given if \c is not followed by an ASCII
838        character, that is, a byte less than 128. (In EBCDIC mode, the code is
839        different, and any byte value is allowed.)
840    
841    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
842        START_OPTIMIZE option, which is now allowed at compile time - but just
843        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
844        to pcregrep and other applications that have no direct access to PCRE
845        options. The new /Y option in pcretest sets this option when calling
846        pcre_compile().
847    
848    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
849        back references. Groups containing recursive back references were forced to
850        be atomic by that change, but in the case of named groups, the amount of
851        memory required was incorrectly computed, leading to "Failed: internal
852        error: code overflow". This has been fixed.
853    
854    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
855        pcretest.c, to avoid build problems in some Borland environments.
856    
857    
858    Version 8.10 25-Jun-2010
859    ------------------------
860    
861    1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
862        THEN.
863    
864    2.  (*ACCEPT) was not working when inside an atomic group.
865    
866    3.  Inside a character class, \B is treated as a literal by default, but
867        faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
868        causes the error). The code is unchanged, but I tidied the documentation.
869    
870    4.  Inside a character class, PCRE always treated \R and \X as literals,
871        whereas Perl faults them if its -w option is set. I have changed PCRE so
872        that it faults them when PCRE_EXTRA is set.
873    
874    5.  Added support for \N, which always matches any character other than
875        newline. (It is the same as "." when PCRE_DOTALL is not set.)
876    
877    6.  When compiling pcregrep with newer versions of gcc which may have
878        FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
879        declared with attribute warn_unused_result" were given. Just casting the
880        result to (void) does not stop the warnings; a more elaborate fudge is
881        needed. I've used a macro to implement this.
882    
883    7.  Minor change to pcretest.c to avoid a compiler warning.
884    
885    8.  Added four artifical Unicode properties to help with an option to make
886        \s etc use properties (see next item). The new properties are: Xan
887        (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
888    
889    9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
890        use Unicode properties. (*UCP) at the start of a pattern can be used to set
891        this option. Modified pcretest to add /W to test this facility. Added
892        REG_UCP to make it available via the POSIX interface.
893    
894    10. Added --line-buffered to pcregrep.
895    
896    11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
897        studied, and the match started with a letter with a code point greater than
898        127 whose first byte was different to the first byte of the other case of
899        the letter, the other case of this starting letter was not recognized
900        (#976).
901    
902    12. If a pattern that was studied started with a repeated Unicode property
903        test, for example, \p{Nd}+, there was the theoretical possibility of
904        setting up an incorrect bitmap of starting bytes, but fortunately it could
905        not have actually happened in practice until change 8 above was made (it
906        added property types that matched character-matching opcodes).
907    
908    13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
909        possible starting bytes for non-anchored patterns.
910    
911    14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
912        \R, and also a number of cases that involve Unicode properties, both
913        explicit and implicit when PCRE_UCP is set.
914    
915    15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
916        input, it could crash or give wrong results if characters with values
917        greater than 0xc0 were present in the subject string. (Detail: it assumed
918        UTF-8 input when processing these items.)
919    
920    16. Added a lot of (int) casts to avoid compiler warnings in systems where
921        size_t is 64-bit (#991).
922    
923    17. Added a check for running out of memory when PCRE is compiled with
924        --disable-stack-for-recursion (#990).
925    
926    18. If the last data line in a file for pcretest does not have a newline on
927        the end, a newline was missing in the output.
928    
929    19. The default pcre_chartables.c file recognizes only ASCII characters (values
930        less than 128) in its various bitmaps. However, there is a facility for
931        generating tables according to the current locale when PCRE is compiled. It
932        turns out that in some environments, 0x85 and 0xa0, which are Unicode space
933        characters, are recognized by isspace() and therefore were getting set in
934        these tables, and indeed these tables seem to approximate to ISO 8859. This
935        caused a problem in UTF-8 mode when pcre_study() was used to create a list
936        of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
937        which of course cannot start UTF-8 characters. I have changed the code so
938        that only real ASCII characters (less than 128) and the correct starting
939        bytes for UTF-8 encodings are set for characters greater than 127 when in
940        UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
941        altogether.)
942    
943    20. Added the /T option to pcretest so as to be able to run tests with non-
944        standard character tables, thus making it possible to include the tests
945        used for 19 above in the standard set of tests.
946    
947    21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
948        reference to a subpattern the other side of a comment that contains an
949        opening parenthesis caused either an internal compiling error, or a
950        reference to the wrong subpattern.
951    
952    
953    Version 8.02 19-Mar-2010
954    ------------------------
955    
956    1.  The Unicode data tables have been updated to Unicode 5.2.0.
957    
958    2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
959        configured.
960    
961    3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
962        original author of that file, following a query about its status.
963    
964    4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
965        inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
966    
967    5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
968        quantifier applied to a forward-referencing subroutine call, could compile
969        incorrect code or give the error "internal error: previously-checked
970        referenced subpattern not found".
971    
972    6.  Both MS Visual Studio and Symbian OS have problems with initializing
973        variables to point to external functions. For these systems, therefore,
974        pcre_malloc etc. are now initialized to local functions that call the
975        relevant global functions.
976    
977    7.  There were two entries missing in the vectors called coptable and poptable
978        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
979        I've fixed the data, and added a kludgy way of testing at compile time that
980        the lengths are correct (equal to the number of opcodes).
981    
982    8.  Following on from 7, I added a similar kludge to check the length of the
983        eint vector in pcreposix.c.
984    
985    9.  Error texts for pcre_compile() are held as one long string to avoid too
986        much relocation at load time. To find a text, the string is searched,
987        counting zeros. There was no check for running off the end of the string,
988        which could happen if a new error number was added without updating the
989        string.
990    
991    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
992    
993    11. \K was not working if it appeared in an atomic group or in a group that
994        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
995        \K is "not well defined" if used in an assertion. PCRE now accepts it if
996        the assertion is positive, but not if it is negative.
997    
998    12. Change 11 fortuitously reduced the size of the stack frame used in the
999        "match()" function of pcre_exec.c by one pointer. Forthcoming
1000        implementation of support for (*MARK) will need an extra pointer on the
1001        stack; I have reserved it now, so that the stack frame size does not
1002        decrease.
1003    
1004    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
1005        item in branch that calls a recursion is a subroutine call - as in the
1006        second branch in the above example - was incorrectly given the compile-
1007        time error "recursive call could loop indefinitely" because pcre_compile()
1008        was not correctly checking the subroutine for matching a non-empty string.
1009    
1010    14. The checks for overrunning compiling workspace could trigger after an
1011        overrun had occurred. This is a "should never occur" error, but it can be
1012        triggered by pathological patterns such as hundreds of nested parentheses.
1013        The checks now trigger 100 bytes before the end of the workspace.
1014    
1015    15. Fix typo in configure.ac: "srtoq" should be "strtoq".
1016    
1017    
1018    Version 8.01 19-Jan-2010
1019    ------------------------
1020    
1021    1.  If a pattern contained a conditional subpattern with only one branch (in
1022        particular, this includes all (*DEFINE) patterns), a call to pcre_study()
1023        computed the wrong minimum data length (which is of course zero for such
1024        subpatterns). This could cause incorrect "no match" results.
1025    
1026    2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
1027        the pattern is reset in the first branch, pcre_compile() failed with
1028        "internal error: code overflow at offset...". This happened only when
1029        the reset was to the original external option setting. (An optimization
1030        abstracts leading options settings into an external setting, which was the
1031        cause of this.)
1032    
1033    3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
1034        of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
1035        assertion pattern did not match (meaning that the assertion was true), it
1036        was incorrectly treated as false if the SKIP had been reached during the
1037        matching. This also applied to assertions used as conditions.
1038    
1039    4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
1040        assertion subpattern, including such a pattern used as a condition,
1041        unpredictable results occurred, instead of the error return
1042        PCRE_ERROR_DFA_UITEM.
1043    
1044    5.  The C++ GlobalReplace function was not working like Perl for the special
1045        situation when an empty string is matched. It now does the fancy magic
1046        stuff that is necessary.
1047    
1048    6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
1049        removed. (These were left over from very, very early versions of PCRE.)
1050    
1051    7.  Some cosmetic changes to the code to make life easier when compiling it
1052        as part of something else:
1053    
1054        (a) Change DEBUG to PCRE_DEBUG.
1055    
1056        (b) In pcre_compile(), rename the member of the "branch_chain" structure
1057            called "current" as "current_branch", to prevent a collision with the
1058            Linux macro when compiled as a kernel module.
1059    
1060        (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
1061            prevent a collision with the Linux macro when compiled as a kernel
1062            module.
1063    
1064    8.  In pcre_compile() there are some checks for integer overflows that used to
1065        cast potentially large values to (double). This has been changed to that
1066        when building, a check for int64_t is made, and if it is found, it is used
1067        instead, thus avoiding the use of floating point arithmetic. (There is no
1068        other use of FP in PCRE.) If int64_t is not found, the fallback is to
1069        double.
1070    
1071    9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
1072        2005 (difference between two addresses compared to an unsigned value).
1073    
1074    10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
1075        custom one, because of the following reported problem in Windows:
1076    
1077          - libbz2 uses the Pascal calling convention (WINAPI) for the functions
1078              under Win32.
1079          - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
1080              therefore missing the function definition.
1081          - The compiler thus generates a "C" signature for the test function.
1082          - The linker fails to find the "C" function.
1083          - PCRE fails to configure if asked to do so against libbz2.
1084    
1085    11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
1086        messages were output:
1087    
1088          Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
1089          rerunning libtoolize, to keep the correct libtool macros in-tree.
1090          Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
1091    
1092        I have done both of these things.
1093    
1094    12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
1095        most of the time, it *can* run out if it is given a pattern that contains a
1096        runaway infinite recursion. I updated the discussion in the pcrestack man
1097        page.
1098    
1099    13. Now that we have gone to the x.xx style of version numbers, the minor
1100        version may start with zero. Using 08 or 09 is a bad idea because users
1101        might check the value of PCRE_MINOR in their code, and 08 or 09 may be
1102        interpreted as invalid octal numbers. I've updated the previous comment in
1103        configure.ac, and also added a check that gives an error if 08 or 09 are
1104        used.
1105    
1106    14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
1107        causing partial matching to fail when the end of the subject matched \W
1108        in a UTF-8 pattern where \W was quantified with a minimum of 3.
1109    
1110    15. There were some discrepancies between the declarations in pcre_internal.h
1111        of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
1112        their definitions. The declarations used "const uschar *" and the
1113        definitions used USPTR. Even though USPTR is normally defined as "const
1114        unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
1115        reported that: "This difference in casting confuses some C++ compilers, for
1116        example, SunCC recognizes above declarations as different functions and
1117        generates broken code for hbpcre." I have changed the declarations to use
1118        USPTR.
1119    
1120    16. GNU libtool is named differently on some systems. The autogen.sh script now
1121        tries several variants such as glibtoolize (MacOSX) and libtoolize1x
1122        (FreeBSD).
1123    
1124    17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
1125        (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
1126        comment: "Figure out how to create a longlong from a string: strtoll and
1127        equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
1128        instance, but it only takes 2 args instead of 3!"
1129    
1130    18. A subtle bug concerned with back references has been fixed by a change of
1131        specification, with a corresponding code fix. A pattern such as
1132        ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
1133        refers, was giving matches when it shouldn't. For example, xa=xaaa would
1134        match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
1135        same bug. Such groups have to be quantified to be useful, or contained
1136        inside another quantified group. (If there's no repetition, the reference
1137        can never match.) The problem arises because, having left the group and
1138        moved on to the rest of the pattern, a later failure that backtracks into
1139        the group uses the captured value from the final iteration of the group
1140        rather than the correct earlier one. I have fixed this in PCRE by forcing
1141        any group that contains a reference to itself to be an atomic group; that
1142        is, there cannot be any backtracking into it once it has completed. This is
1143        similar to recursive and subroutine calls.
1144    
1145    
1146    Version 8.00 19-Oct-09
1147    ----------------------
1148    
1149    1.  The table for translating pcre_compile() error codes into POSIX error codes
1150        was out-of-date, and there was no check on the pcre_compile() error code
1151        being within the table. This could lead to an OK return being given in
1152        error.
1153    
1154    2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
1155        "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
1156        in a Windows environment.
1157    
1158    3.  The pcregrep --count option prints the count for each file even when it is
1159        zero, as does GNU grep. However, pcregrep was also printing all files when
1160        --files-with-matches was added. Now, when both options are given, it prints
1161        counts only for those files that have at least one match. (GNU grep just
1162        prints the file name in this circumstance, but including the count seems
1163        more useful - otherwise, why use --count?) Also ensured that the
1164        combination -clh just lists non-zero counts, with no names.
1165    
1166    4.  The long form of the pcregrep -F option was incorrectly implemented as
1167        --fixed_strings instead of --fixed-strings. This is an incompatible change,
1168        but it seems right to fix it, and I didn't think it was worth preserving
1169        the old behaviour.
1170    
1171    5.  The command line items --regex=pattern and --regexp=pattern were not
1172        recognized by pcregrep, which required --regex pattern or --regexp pattern
1173        (with a space rather than an '='). The man page documented the '=' forms,
1174        which are compatible with GNU grep; these now work.
1175    
1176    6.  No libpcreposix.pc file was created for pkg-config; there was just
1177        libpcre.pc and libpcrecpp.pc. The omission has been rectified.
1178    
1179    7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
1180        when UCP support is not needed, by modifying the Python script that
1181        generates it from Unicode data files. This should not matter if the module
1182        is correctly used as a library, but I received one complaint about 50K of
1183        unwanted data. My guess is that the person linked everything into his
1184        program rather than using a library. Anyway, it does no harm.
1185    
1186    8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
1187        was a minimum greater than 1 for a wide character in a possessive
1188        repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
1189        which had an unlimited repeat of a nested, fixed maximum repeat of a wide
1190        character. Chaos in the form of incorrect output or a compiling loop could
1191        result.
1192    
1193    9.  The restrictions on what a pattern can contain when partial matching is
1194        requested for pcre_exec() have been removed. All patterns can now be
1195        partially matched by this function. In addition, if there are at least two
1196        slots in the offset vector, the offset of the earliest inspected character
1197        for the match and the offset of the end of the subject are set in them when
1198        PCRE_ERROR_PARTIAL is returned.
1199    
1200    10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
1201        synonymous with PCRE_PARTIAL, for backwards compatibility, and
1202        PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
1203        and may be more useful for multi-segment matching.
1204    
1205    11. Partial matching with pcre_exec() is now more intuitive. A partial match
1206        used to be given if ever the end of the subject was reached; now it is
1207        given only if matching could not proceed because another character was
1208        needed. This makes a difference in some odd cases such as Z(*FAIL) with the
1209        string "Z", which now yields "no match" instead of "partial match". In the
1210        case of pcre_dfa_exec(), "no match" is given if every matching path for the
1211        final character ended with (*FAIL).
1212    
1213    12. Restarting a match using pcre_dfa_exec() after a partial match did not work
1214        if the pattern had a "must contain" character that was already found in the
1215        earlier partial match, unless partial matching was again requested. For
1216        example, with the pattern /dog.(body)?/, the "must contain" character is
1217        "g". If the first part-match was for the string "dog", restarting with
1218        "sbody" failed. This bug has been fixed.
1219    
1220    13. The string returned by pcre_dfa_exec() after a partial match has been
1221        changed so that it starts at the first inspected character rather than the
1222        first character of the match. This makes a difference only if the pattern
1223        starts with a lookbehind assertion or \b or \B (\K is not supported by
1224        pcre_dfa_exec()). It's an incompatible change, but it makes the two
1225        matching functions compatible, and I think it's the right thing to do.
1226    
1227    14. Added a pcredemo man page, created automatically from the pcredemo.c file,
1228        so that the demonstration program is easily available in environments where
1229        PCRE has not been installed from source.
1230    
1231    15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
1232        libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
1233        library.
1234    
1235    16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
1236        It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
1237        is not the first non-POSIX option to be added. Clearly some people find
1238        these options useful.
1239    
1240    17. If a caller to the POSIX matching function regexec() passes a non-zero
1241        value for nmatch with a NULL value for pmatch, the value of
1242        nmatch is forced to zero.
1243    
1244    18. RunGrepTest did not have a test for the availability of the -u option of
1245        the diff command, as RunTest does. It now checks in the same way as
1246        RunTest, and also checks for the -b option.
1247    
1248    19. If an odd number of negated classes containing just a single character
1249        interposed, within parentheses, between a forward reference to a named
1250        subpattern and the definition of the subpattern, compilation crashed with
1251        an internal error, complaining that it could not find the referenced
1252        subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
1253        [The bug was that it was starting one character too far in when skipping
1254        over the character class, thus treating the ] as data rather than
1255        terminating the class. This meant it could skip too much.]
1256    
1257    20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
1258        /g option in pcretest when the pattern contains \K, which makes it possible
1259        to have an empty string match not at the start, even when the pattern is
1260        anchored. Updated pcretest and pcredemo to use this option.
1261    
1262    21. If the maximum number of capturing subpatterns in a recursion was greater
1263        than the maximum at the outer level, the higher number was returned, but
1264        with unset values at the outer level. The correct (outer level) value is
1265        now given.
1266    
1267    22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
1268        PCRE did not set those parentheses (unlike Perl). I have now found a way to
1269        make it do so. The string so far is captured, making this feature
1270        compatible with Perl.
1271    
1272    23. The tests have been re-organized, adding tests 11 and 12, to make it
1273        possible to check the Perl 5.10 features against Perl 5.10.
1274    
1275    24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
1276        pattern matches a fixed length string. PCRE did not allow this; now it
1277        does. Neither allows recursion.
1278    
1279    25. I finally figured out how to implement a request to provide the minimum
1280        length of subject string that was needed in order to match a given pattern.
1281        (It was back references and recursion that I had previously got hung up
1282        on.) This code has now been added to pcre_study(); it finds a lower bound
1283        to the length of subject needed. It is not necessarily the greatest lower
1284        bound, but using it to avoid searching strings that are too short does give
1285        some useful speed-ups. The value is available to calling programs via
1286        pcre_fullinfo().
1287    
1288    26. While implementing 25, I discovered to my embarrassment that pcretest had
1289        not been passing the result of pcre_study() to pcre_dfa_exec(), so the
1290        study optimizations had never been tested with that matching function.
1291        Oops. What is worse, even when it was passed study data, there was a bug in
1292        pcre_dfa_exec() that meant it never actually used it. Double oops. There
1293        were also very few tests of studied patterns with pcre_dfa_exec().
1294    
1295    27. If (?| is used to create subpatterns with duplicate numbers, they are now
1296        allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
1297        on the other side of the coin, they are no longer allowed to have different
1298        names, because these cannot be distinguished in PCRE, and this has caused
1299        confusion. (This is a difference from Perl.)
1300    
1301    28. When duplicate subpattern names are present (necessarily with different
1302        numbers, as required by 27 above), and a test is made by name in a
1303        conditional pattern, either for a subpattern having been matched, or for
1304        recursion in such a pattern, all the associated numbered subpatterns are
1305        tested, and the overall condition is true if the condition is true for any
1306        one of them. This is the way Perl works, and is also more like the way
1307        testing by number works.
1308    
1309    
1310    Version 7.9 11-Apr-09
1311    ---------------------
1312    
1313    1.  When building with support for bzlib/zlib (pcregrep) and/or readline
1314        (pcretest), all targets were linked against these libraries. This included
1315        libpcre, libpcreposix, and libpcrecpp, even though they do not use these
1316        libraries. This caused unwanted dependencies to be created. This problem
1317        has been fixed, and now only pcregrep is linked with bzlib/zlib and only
1318        pcretest is linked with readline.
1319    
1320    2.  The "typedef int BOOL" in pcre_internal.h that was included inside the
1321        "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
1322        moved outside it again, because FALSE and TRUE are already defined in AIX,
1323        but BOOL is not.
1324    
1325    3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
1326        PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
1327    
1328    4.  The pcregrep documentation said spaces were inserted as well as colons (or
1329        hyphens) following file names and line numbers when outputting matching
1330        lines. This is not true; no spaces are inserted. I have also clarified the
1331        wording for the --colour (or --color) option.
1332    
1333    5.  In pcregrep, when --colour was used with -o, the list of matching strings
1334        was not coloured; this is different to GNU grep, so I have changed it to be
1335        the same.
1336    
1337    6.  When --colo(u)r was used in pcregrep, only the first matching substring in
1338        each matching line was coloured. Now it goes on to look for further matches
1339        of any of the test patterns, which is the same behaviour as GNU grep.
1340    
1341    7.  A pattern that could match an empty string could cause pcregrep to loop; it
1342        doesn't make sense to accept an empty string match in pcregrep, so I have
1343        locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
1344        seems to be how GNU grep behaves.
1345    
1346    8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
1347        start or after a newline", because the conditional assertion was not being
1348        correctly handled. The rule now is that both the assertion and what follows
1349        in the first alternative must satisfy the test.
1350    
1351    9.  If auto-callout was enabled in a pattern with a conditional group whose
1352        condition was an assertion, PCRE could crash during matching, both with
1353        pcre_exec() and pcre_dfa_exec().
1354    
1355    10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
1356        used for matching.
1357    
1358    11. Unicode property support in character classes was not working for
1359        characters (bytes) greater than 127 when not in UTF-8 mode.
1360    
1361    12. Added the -M command line option to pcretest.
1362    
1363    14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
1364    
1365    15. Added the PCRE_NO_START_OPTIMIZE match-time option.
1366    
1367    16. Added comments and documentation about mis-use of no_arg in the C++
1368        wrapper.
1369    
1370    17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
1371        from Martin Jerabek that uses macro names for all relevant character and
1372        string constants.
1373    
1374    18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
1375        SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
1376        SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
1377        these, but not everybody uses configure.
1378    
1379    19. A conditional group that had only one branch was not being correctly
1380        recognized as an item that could match an empty string. This meant that an
1381        enclosing group might also not be so recognized, causing infinite looping
1382        (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
1383        with the subject "ab", where knowledge that the repeated group can match
1384        nothing is needed in order to break the loop.
1385    
1386    20. If a pattern that was compiled with callouts was matched using pcre_dfa_
1387        exec(), but without supplying a callout function, matching went wrong.
1388    
1389    21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
1390        leak if the size of the offset vector was greater than 30. When the vector
1391        is smaller, the saved offsets during recursion go onto a local stack
1392        vector, but for larger vectors malloc() is used. It was failing to free
1393        when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
1394        error, in fact).
1395    
1396    22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
1397        heapframe that is used only when UTF-8 support is enabled. This caused no
1398        problem, but was untidy.
1399    
1400    23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
1401        CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
1402        included within another project.
1403    
1404    24. Steven Van Ingelgem's patches to add more options to the CMake support,
1405        slightly modified by me:
1406    
1407          (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
1408              not building pcregrep.
1409    
1410          (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
1411              if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
1412    
1413    25. Forward references, both numeric and by name, in patterns that made use of
1414        duplicate group numbers, could behave incorrectly or give incorrect errors,
1415        because when scanning forward to find the reference group, PCRE was not
1416        taking into account the duplicate group numbers. A pattern such as
1417        ^X(?3)(a)(?|(b)|(q))(Y) is an example.
1418    
1419    26. Changed a few more instances of "const unsigned char *" to USPTR, making
1420        the feature of a custom pointer more persuasive (as requested by a user).
1421    
1422    27. Wrapped the definitions of fileno and isatty for Windows, which appear in
1423        pcretest.c, inside #ifndefs, because it seems they are sometimes already
1424        pre-defined.
1425    
1426    28. Added support for (*UTF8) at the start of a pattern.
1427    
1428    29. Arrange for flags added by the "release type" setting in CMake to be shown
1429        in the configuration summary.
1430    
1431    
1432    Version 7.8 05-Sep-08
1433    ---------------------
1434    
1435    1.  Replaced UCP searching code with optimized version as implemented for Ad
1436        Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
1437        stage table and inline lookup instead of a function, giving speed ups of 2
1438        to 5 times on some simple patterns that I tested. Permission was given to
1439        distribute the MultiStage2.py script that generates the tables (it's not in
1440        the tarball, but is in the Subversion repository).
1441    
1442    2.  Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
1443        scripts.
1444    
1445    3.  Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
1446        a group with a zero qualifier. The result of the study could be incorrect,
1447        or the function might crash, depending on the pattern.
1448    
1449    4.  Caseless matching was not working for non-ASCII characters in back
1450        references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
1451        It now works when Unicode Property Support is available.
1452    
1453    5.  In pcretest, an escape such as \x{de} in the data was always generating
1454        a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
1455        non-UTF-8 mode. If the value is greater than 255, it gives a warning about
1456        truncation.
1457    
1458    6.  Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
1459    
1460    7.  Added two (int) casts to pcregrep when printing the difference of two
1461        pointers, in case they are 64-bit values.
1462    
1463    8.  Added comments about Mac OS X stack usage to the pcrestack man page and to
1464        test 2 if it fails.
1465    
1466    9.  Added PCRE_CALL_CONVENTION just before the names of all exported functions,
1467        and a #define of that name to empty if it is not externally set. This is to
1468        allow users of MSVC to set it if necessary.
1469    
1470    10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
1471        the convenience functions in the pcre_get.c source file.
1472    
1473    11. An option change at the start of a pattern that had top-level alternatives
1474        could cause overwriting and/or a crash. This command provoked a crash in
1475        some environments:
1476    
1477          printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
1478    
1479        This potential security problem was recorded as CVE-2008-2371.
1480    
1481    12. For a pattern where the match had to start at the beginning or immediately
1482        after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
1483        pcre_dfa_exec() could read past the end of the passed subject if there was
1484        no match. To help with detecting such bugs (e.g. with valgrind), I modified
1485        pcretest so that it places the subject at the end of its malloc-ed buffer.
1486    
1487    13. The change to pcretest in 12 above threw up a couple more cases when pcre_
1488        exec() might read past the end of the data buffer in UTF-8 mode.
1489    
1490    14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
1491        the data contained the byte 0x85 as part of a UTF-8 character within its
1492        first line. This applied both to normal and DFA matching.
1493    
1494    15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
1495        /^[^d]*?$/8 failed to match "abc".
1496    
1497    16. Added a missing copyright notice to pcrecpp_internal.h.
1498    
1499    17. Make it more clear in the documentation that values returned from
1500        pcre_exec() in ovector are byte offsets, not character counts.
1501    
1502    18. Tidied a few places to stop certain compilers from issuing warnings.
1503    
1504    19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
1505        supplied by Stefan Weber. I made a further small update for 7.8 because
1506        there is a change of source arrangements: the pcre_searchfuncs.c module is
1507        replaced by pcre_ucd.c.
1508    
1509    
1510    Version 7.7 07-May-08
1511    ---------------------
1512    
1513    1.  Applied Craig's patch to sort out a long long problem: "If we can't convert
1514        a string to a long long, pretend we don't even have a long long." This is
1515        done by checking for the strtoq, strtoll, and _strtoi64 functions.
1516    
1517    2.  Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
1518        pre-7.6 versions, which defined a global no_arg variable instead of putting
1519        it in the RE class. (See also #8 below.)
1520    
1521    3.  Remove a line of dead code, identified by coverity and reported by Nuno
1522        Lopes.
1523    
1524    4.  Fixed two related pcregrep bugs involving -r with --include or --exclude:
1525    
1526        (1) The include/exclude patterns were being applied to the whole pathnames
1527            of files, instead of just to the final components.
1528    
1529        (2) If there was more than one level of directory, the subdirectories were
1530            skipped unless they satisfied the include/exclude conditions. This is
1531            inconsistent with GNU grep (and could even be seen as contrary to the
1532            pcregrep specification - which I improved to make it absolutely clear).
1533            The action now is always to scan all levels of directory, and just
1534            apply the include/exclude patterns to regular files.
1535    
1536    5.  Added the --include_dir and --exclude_dir patterns to pcregrep, and used
1537        --exclude_dir in the tests to avoid scanning .svn directories.
1538    
1539    6.  Applied Craig's patch to the QuoteMeta function so that it escapes the
1540        NUL character as backslash + 0 rather than backslash + NUL, because PCRE
1541        doesn't support NULs in patterns.
1542    
1543    7.  Added some missing "const"s to declarations of static tables in
1544        pcre_compile.c and pcre_dfa_exec.c.
1545    
1546    8.  Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
1547        caused by fix #2  above. (Subsequently also a second patch to fix the
1548        first patch. And a third patch - this was a messy problem.)
1549    
1550    9.  Applied Craig's patch to remove the use of push_back().
1551    
1552    10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
1553        matching function regexec().
1554    
1555    11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
1556        which, however, unlike Perl's \g{...}, are subroutine calls, not back
1557        references. PCRE supports relative numbers with this syntax (I don't think
1558        Oniguruma does).
1559    
1560    12. Previously, a group with a zero repeat such as (...){0} was completely
1561        omitted from the compiled regex. However, this means that if the group
1562        was called as a subroutine from elsewhere in the pattern, things went wrong
1563        (an internal error was given). Such groups are now left in the compiled
1564        pattern, with a new opcode that causes them to be skipped at execution
1565        time.
1566    
1567    13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
1568        to the way PCRE behaves:
1569    
1570        (a) A lone ] character is dis-allowed (Perl treats it as data).
1571    
1572        (b) A back reference to an unmatched subpattern matches an empty string
1573            (Perl fails the current match path).
1574    
1575        (c) A data ] in a character class must be notated as \] because if the
1576            first data character in a class is ], it defines an empty class. (In
1577            Perl it is not possible to have an empty class.) The empty class []
1578            never matches; it forces failure and is equivalent to (*FAIL) or (?!).
1579            The negative empty class [^] matches any one character, independently
1580            of the DOTALL setting.
1581    
1582    14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
1583        non-existent subpattern following a character class starting with ']' and
1584        containing () gave an internal compiling error instead of "reference to
1585        non-existent subpattern". Fortunately, when the pattern did exist, the
1586        compiled code was correct. (When scanning forwards to check for the
1587        existencd of the subpattern, it was treating the data ']' as terminating
1588        the class, so got the count wrong. When actually compiling, the reference
1589        was subsequently set up correctly.)
1590    
1591    15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
1592        it was being rejected as not supported by pcre_dfa_exec(), even though
1593        other assertions are supported. I have made pcre_dfa_exec() support
1594        (*FAIL).
1595    
1596    16. The implementation of 13c above involved the invention of a new opcode,
1597        OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
1598        cannot be changed at match time, I realized I could make a small
1599        improvement to matching performance by compiling OP_ALLANY instead of
1600        OP_ANY for "." when DOTALL was set, and then removing the runtime tests
1601        on the OP_ANY path.
1602    
1603    17. Compiling pcretest on Windows with readline support failed without the
1604        following two fixes: (1) Make the unistd.h include conditional on
1605        HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
1606    
1607    18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
1608        ncurses library to be included for pcretest when ReadLine support is
1609        requested, but also to allow for it to be overridden. This patch came from
1610        Daniel Bergström.
1611    
1612    19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
1613        as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
1614        any errors with the current Unicode tables. Thanks to Peter Kankowski for
1615        spotting this.
1616    
1617    
1618    Version 7.6 28-Jan-08
1619    ---------------------
1620    
1621    1.  A character class containing a very large number of characters with
1622        codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
1623        overflow.
1624    
1625    2.  Patch to cut out the "long long" test in pcrecpp_unittest when
1626        HAVE_LONG_LONG is not defined.
1627    
1628    3.  Applied Christian Ehrlicher's patch to update the CMake build files to
1629        bring them up to date and include new features. This patch includes:
1630    
1631        - Fixed PH's badly added libz and libbz2 support.
1632        - Fixed a problem with static linking.
1633        - Added pcredemo. [But later removed - see 7 below.]
1634        - Fixed dftables problem and added an option.
1635        - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
1636            HAVE_LONG_LONG.
1637        - Added readline support for pcretest.
1638        - Added an listing of the option settings after cmake has run.
1639    
1640    4.  A user submitted a patch to Makefile that makes it easy to create
1641        "pcre.dll" under mingw when using Configure/Make. I added stuff to
1642        Makefile.am that cause it to include this special target, without
1643        affecting anything else. Note that the same mingw target plus all
1644        the other distribution libraries and programs are now supported
1645        when configuring with CMake (see 6 below) instead of with
1646        Configure/Make.
1647    
1648    5.  Applied Craig's patch that moves no_arg into the RE class in the C++ code.
1649        This is an attempt to solve the reported problem "pcrecpp::no_arg is not
1650        exported in the Windows port". It has not yet been confirmed that the patch
1651        solves the problem, but it does no harm.
1652    
1653    6.  Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
1654        NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
1655        with CMake, and also correct the comment about stack recursion.
1656    
1657    7.  Remove the automatic building of pcredemo from the ./configure system and
1658        from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
1659        of a program that users should build themselves after PCRE is installed, so
1660        building it automatically is not really right. What is more, it gave
1661        trouble in some build environments.
1662    
1663    8.  Further tidies to CMakeLists.txt from Sheri and Christian.
1664    
1665    
1666    Version 7.5 10-Jan-08
1667    ---------------------
1668    
1669    1.  Applied a patch from Craig: "This patch makes it possible to 'ignore'
1670        values in parens when parsing an RE using the C++ wrapper."
1671    
1672    2.  Negative specials like \S did not work in character classes in UTF-8 mode.
1673        Characters greater than 255 were excluded from the class instead of being
1674        included.
1675    
1676    3.  The same bug as (2) above applied to negated POSIX classes such as
1677        [:^space:].
1678    
1679    4.  PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
1680        defined or documented. It seems to have been a typo for PCRE_STATIC, so
1681        I have changed it.
1682    
1683    5.  The construct (?&) was not diagnosed as a syntax error (it referenced the
1684        first named subpattern) and a construct such as (?&a) would reference the
1685        first named subpattern whose name started with "a" (in other words, the
1686        length check was missing). Both these problems are fixed. "Subpattern name
1687        expected" is now given for (?&) (a zero-length name), and this patch also
1688        makes it give the same error for \k'' (previously it complained that that
1689        was a reference to a non-existent subpattern).
1690    
1691    6.  The erroneous patterns (?+-a) and (?-+a) give different error messages;
1692        this is right because (?- can be followed by option settings as well as by
1693        digits. I have, however, made the messages clearer.
1694    
1695    7.  Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
1696        than the number used in the conditional) now cause a compile-time error.
1697        This is actually not compatible with Perl, which accepts such patterns, but
1698        treats the conditional as always being FALSE (as PCRE used to), but it
1699        seems to me that giving a diagnostic is better.
1700    
1701    8.  Change "alphameric" to the more common word "alphanumeric" in comments
1702        and messages.
1703    
1704    9.  Fix two occurrences of "backslash" in comments that should have been
1705        "backspace".
1706    
1707    10. Remove two redundant lines of code that can never be obeyed (their function
1708        was moved elsewhere).
1709    
1710    11. The program that makes PCRE's Unicode character property table had a bug
1711        which caused it to generate incorrect table entries for sequences of
1712        characters that have the same character type, but are in different scripts.
1713        It amalgamated them into a single range, with the script of the first of
1714        them. In other words, some characters were in the wrong script. There were
1715        thirteen such cases, affecting characters in the following ranges:
1716    
1717          U+002b0 - U+002c1
1718          U+0060c - U+0060d
1719          U+0061e - U+00612
1720          U+0064b - U+0065e
1721          U+0074d - U+0076d
1722          U+01800 - U+01805
1723          U+01d00 - U+01d77
1724          U+01d9b - U+01dbf
1725          U+0200b - U+0200f
1726          U+030fc - U+030fe
1727          U+03260 - U+0327f
1728          U+0fb46 - U+0fbb1
1729          U+10450 - U+1049d
1730    
1731    12. The -o option (show only the matching part of a line) for pcregrep was not
1732        compatible with GNU grep in that, if there was more than one match in a
1733        line, it showed only the first of them. It now behaves in the same way as
1734        GNU grep.
1735    
1736    13. If the -o and -v options were combined for pcregrep, it printed a blank
1737        line for every non-matching line. GNU grep prints nothing, and pcregrep now
1738        does the same. The return code can be used to tell if there were any
1739        non-matching lines.
1740    
1741    14. Added --file-offsets and --line-offsets to pcregrep.
1742    
1743    15. The pattern (?=something)(?R) was not being diagnosed as a potentially
1744        infinitely looping recursion. The bug was that positive lookaheads were not
1745        being skipped when checking for a possible empty match (negative lookaheads
1746        and both kinds of lookbehind were skipped).
1747    
1748    16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
1749        inclusion of <windows.h> to before rather than after the definition of
1750        INVALID_FILE_ATTRIBUTES (patch from David Byron).
1751    
1752    17. Specifying a possessive quantifier with a specific limit for a Unicode
1753        character property caused pcre_compile() to compile bad code, which led at
1754        runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
1755        are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
1756        caused the error; without that there was no problem.
1757    
1758    18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
1759    
1760    19. Added --enable-pcretest-libreadline.
1761    
1762    20. In pcrecpp.cc, the variable 'count' was incremented twice in
1763        RE::GlobalReplace(). As a result, the number of replacements returned was
1764        double what it should be. I removed one of the increments, but Craig sent a
1765        later patch that removed the other one (the right fix) and added unit tests
1766        that check the return values (which was not done before).
1767    
1768    21. Several CMake things:
1769    
1770        (1) Arranged that, when cmake is used on Unix, the libraries end up with
1771            the names libpcre and libpcreposix, not just pcre and pcreposix.
1772    
1773        (2) The above change means that pcretest and pcregrep are now correctly
1774            linked with the newly-built libraries, not previously installed ones.
1775    
1776        (3) Added PCRE_SUPPORT_LIBREADLINE, PCRE_SUPPORT_LIBZ, PCRE_SUPPORT_LIBBZ2.
1777    
1778    22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
1779        crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
1780        UTF-8 newline character). The key issue is that the pattern starts .*;
1781        this means that the match must be either at the beginning, or after a
1782        newline. The bug was in the code for advancing after a failed match and
1783        checking that the new position followed a newline. It was not taking
1784        account of UTF-8 characters correctly.
1785    
1786    23. PCRE was behaving differently from Perl in the way it recognized POSIX
1787        character classes. PCRE was not treating the sequence [:...:] as a
1788        character class unless the ... were all letters. Perl, however, seems to
1789        allow any characters between [: and :], though of course it rejects as
1790        unknown any "names" that contain non-letters, because all the known class
1791        names consist only of letters. Thus, Perl gives an error for [[:1234:]],
1792        for example, whereas PCRE did not - it did not recognize a POSIX character
1793        class. This seemed a bit dangerous, so the code has been changed to be
1794        closer to Perl. The behaviour is not identical to Perl, because PCRE will
1795        diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
1796        treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
1797        Perl does, and where it didn't before.
1798    
1799    24. Rewrite so as to remove the single use of %n from pcregrep because in some
1800        Windows environments %n is disabled by default.
1801    
1802    
1803    Version 7.4 21-Sep-07
1804    ---------------------
1805    
1806    1.  Change 7.3/28 was implemented for classes by looking at the bitmap. This
1807        means that a class such as [\s] counted as "explicit reference to CR or
1808        LF". That isn't really right - the whole point of the change was to try to
1809        help when there was an actual mention of one of the two characters. So now
1810        the change happens only if \r or \n (or a literal CR or LF) character is
1811        encountered.
1812    
1813    2.  The 32-bit options word was also used for 6 internal flags, but the numbers
1814        of both had grown to the point where there were only 3 bits left.
1815        Fortunately, there was spare space in the data structure, and so I have
1816        moved the internal flags into a new 16-bit field to free up more option
1817        bits.
1818    
1819    3.  The appearance of (?J) at the start of a pattern set the DUPNAMES option,
1820        but did not set the internal JCHANGED flag - either of these is enough to
1821        control the way the "get" function works - but the PCRE_INFO_JCHANGED
1822        facility is supposed to tell if (?J) was ever used, so now (?J) at the
1823        start sets both bits.
1824    
1825    4.  Added options (at build time, compile time, exec time) to change \R from
1826        matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
1827    
1828    5.  doc/pcresyntax.html was missing from the distribution.
1829    
1830    6.  Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
1831        compatibility, even though it is no longer used.
1832    
1833    7.  Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
1834        strtoull to pcrecpp.cc to select the available functions in WIN32 when the
1835        windows.h file is present (where different names are used). [This was
1836        reversed later after testing - see 16 below.]
1837    
1838    8.  Changed all #include <config.h> to #include "config.h". There were also
1839        some further <pcre.h> cases that I changed to "pcre.h".
1840    
1841    9.  When pcregrep was used with the --colour option, it missed the line ending
1842        sequence off the lines that it output.
1843    
1844    10. It was pointed out to me that arrays of string pointers cause lots of
1845        relocations when a shared library is dynamically loaded. A technique of
1846        using a single long string with a table of offsets can drastically reduce
1847        these. I have refactored PCRE in four places to do this. The result is
1848        dramatic:
1849    
1850          Originally:                          290
1851          After changing UCP table:            187
1852          After changing error message table:   43
1853          After changing table of "verbs"       36
1854          After changing table of Posix names   22
1855    
1856        Thanks to the folks working on Gregex for glib for this insight.
1857    
1858    11. --disable-stack-for-recursion caused compiling to fail unless -enable-
1859        unicode-properties was also set.
1860    
1861    12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
1862    
1863    13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
1864        checked only for CRLF.
1865    
1866    14. Added casts to pcretest.c to avoid compiler warnings.
1867    
1868    15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
1869    
1870    16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
1871        and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
1872        entirely. This removes changes made in 7 above.
1873    
1874    17. The CMake files have been updated, and there is now more information about
1875        building with CMake in the NON-UNIX-USE document.
1876    
1877    
1878    Version 7.3 28-Aug-07
1879    ---------------------
1880    
1881     1. In the rejigging of the build system that eventually resulted in 7.1, the
1882        line "#include <pcre.h>" was included in pcre_internal.h. The use of angle
1883        brackets there is not right, since it causes compilers to look for an
1884        installed pcre.h, not the version that is in the source that is being
1885        compiled (which of course may be different). I have changed it back to:
1886    
1887          #include "pcre.h"
1888    
1889        I have a vague recollection that the change was concerned with compiling in
1890        different directories, but in the new build system, that is taken care of
1891        by the VPATH setting the Makefile.
1892    
1893     2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
1894        when the subject happened to end in the byte 0x85 (e.g. if the last
1895        character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
1896        characters but of course it shouldn't be taken as a newline when it is part
1897        of another character. The bug was that, for an unlimited repeat of . in
1898        not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
1899        characters when looking for a newline.
1900    
1901     3. A small performance improvement in the DOTALL UTF-8 mode .* case.
1902    
1903     4. Debugging: adjusted the names of opcodes for different kinds of parentheses
1904        in debug output.
1905    
1906     5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
1907        long printing in the pcrecpp unittest when running under MinGW.
1908    
1909     6. ESC_K was left out of the EBCDIC table.
1910    
1911     7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
1912        parentheses; I made it 1000, which seemed large enough. Unfortunately, the
1913        limit also applies to "virtual nesting" when a pattern is recursive, and in
1914        this case 1000 isn't so big. I have been able to remove this limit at the
1915        expense of backing off one optimization in certain circumstances. Normally,
1916        when pcre_exec() would call its internal match() function recursively and
1917        immediately return the result unconditionally, it uses a "tail recursion"
1918        feature to save stack. However, when a subpattern that can match an empty
1919        string has an unlimited repetition quantifier, it no longer makes this
1920        optimization. That gives it a stack frame in which to save the data for
1921        checking that an empty string has been matched. Previously this was taken
1922        from the 1000-entry workspace that had been reserved. So now there is no
1923        explicit limit, but more stack is used.
1924    
1925     8. Applied Daniel's patches to solve problems with the import/export magic
1926        syntax that is required for Windows, and which was going wrong for the
1927        pcreposix and pcrecpp parts of the library. These were overlooked when this
1928        problem was solved for the main library.
1929    
1930     9. There were some crude static tests to avoid integer overflow when computing
1931        the size of patterns that contain repeated groups with explicit upper
1932        limits. As the maximum quantifier is 65535, the maximum group length was
1933        set at 30,000 so that the product of these two numbers did not overflow a
1934        32-bit integer. However, it turns out that people want to use groups that
1935        are longer than 30,000 bytes (though not repeat them that many times).
1936        Change 7.0/17 (the refactoring of the way the pattern size is computed) has
1937        made it possible to implement the integer overflow checks in a much more
1938        dynamic way, which I have now done. The artificial limitation on group
1939        length has been removed - we now have only the limit on the total length of
1940        the compiled pattern, which depends on the LINK_SIZE setting.
1941    
1942    10. Fixed a bug in the documentation for get/copy named substring when
1943        duplicate names are permitted. If none of the named substrings are set, the
1944        functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
1945        empty string.
1946    
1947    11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E
1948        instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error,
1949        because the ] is interpreted as the first data character and the
1950        terminating ] is not found. PCRE has been made compatible with Perl in this
1951        regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could
1952        cause memory overwriting.
1953    
1954    10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty
1955        string has been matched (to stop an infinite loop). It was not recognizing
1956        a conditional subpattern that could match an empty string if that
1957        subpattern was within another subpattern. For example, it looped when
1958        trying to match  (((?(1)X|))*)  but it was OK with  ((?(1)X|)*)  where the
1959        condition was not nested. This bug has been fixed.
1960    
1961    12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
1962        past the start of the subject in the presence of bytes with the top bit
1963        set, for example "\x8aBCD".
1964    
1965    13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
1966        (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
1967    
1968    14. Optimized (?!) to (*FAIL).
1969    
1970    15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
1971        This restricts code points to be within the range 0 to 0x10FFFF, excluding
1972        the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
1973        full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
1974        does: it's just the validity check that is more restrictive.
1975    
1976    16. Inserted checks for integer overflows during escape sequence (backslash)
1977        processing, and also fixed erroneous offset values for syntax errors during
1978        backslash processing.
1979    
1980    17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
1981        for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
1982    
1983    18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
1984        caused an overrun.
1985    
1986    19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
1987        something other than just ASCII characters) inside a group that had an
1988        unlimited repeat caused a loop at compile time (while checking to see
1989        whether the group could match an empty string).
1990    
1991    20. Debugging a pattern containing \p or \P could cause a crash. For example,
1992        [\P{Any}] did so. (Error in the code for printing property names.)
1993    
1994    21. An orphan \E inside a character class could cause a crash.
1995    
1996    22. A repeated capturing bracket such as (A)? could cause a wild memory
1997        reference during compilation.
1998    
1999    23. There are several functions in pcre_compile() that scan along a compiled
2000        expression for various reasons (e.g. to see if it's fixed length for look
2001        behind). There were bugs in these functions when a repeated \p or \P was
2002        present in the pattern. These operators have additional parameters compared
2003        with \d, etc, and these were not being taken into account when moving along
2004        the compiled data. Specifically:
2005    
2006        (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
2007            length.
2008    
2009        (b) An item such as \pL+ within a repeated group could cause crashes or
2010            loops.
2011    
2012        (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
2013            "reference to non-existent subpattern" error.
2014    
2015        (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
2016    
2017    24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
2018        characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
2019    
2020    25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
2021    
2022    26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
2023        character were causing crashes (broken optimization).
2024    
2025    27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
2026        \p or \P) caused a compile-time loop.
2027    
2028    28. More problems have arisen in unanchored patterns when CRLF is a valid line
2029        break. For example, the unstudied pattern [\r\n]A does not match the string
2030        "\r\nA" because change 7.0/46 below moves the current point on by two
2031        characters after failing to match at the start. However, the pattern \nA
2032        *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
2033        the same is true. There doesn't seem any very clean way out of this, but
2034        what I have chosen to do makes the common cases work: PCRE now takes note
2035        of whether there can be an explicit match for \r or \n anywhere in the
2036        pattern, and if so, 7.0/46 no longer applies. As part of this change,
2037        there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
2038        pattern has explicit CR or LF references.
2039    
2040    29. Added (*CR) etc for changing newline setting at start of pattern.
2041    
2042    
2043    Version 7.2 19-Jun-07
2044    ---------------------
2045    
2046     1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
2047        which is apparently normally available under Windows.
2048    
2049     2. Re-jig the pcregrep tests with different newline settings in an attempt
2050        to make them independent of the local environment's newline setting.
2051    
2052     3. Add code to configure.ac to remove -g from the CFLAGS default settings.
2053    
2054     4. Some of the "internals" tests were previously cut out when the link size
2055        was not 2, because the output contained actual offsets. The recent new
2056        "Z" feature of pcretest means that these can be cut out, making the tests
2057        usable with all link sizes.
2058    
2059     5. Implemented Stan Switzer's goto replacement for longjmp() when not using
2060        stack recursion. This gives a massive performance boost under BSD, but just
2061        a small improvement under Linux. However, it saves one field in the frame
2062        in all cases.
2063    
2064     6. Added more features from the forthcoming Perl 5.10:
2065    
2066        (a) (?-n) (where n is a string of digits) is a relative subroutine or
2067            recursion call. It refers to the nth most recently opened parentheses.
2068    
2069        (b) (?+n) is also a relative subroutine call; it refers to the nth next
2070            to be opened parentheses.
2071    
2072        (c) Conditions that refer to capturing parentheses can be specified
2073            relatively, for example, (?(-2)... or (?(+3)...
2074    
2075        (d) \K resets the start of the current match so that everything before
2076            is not part of it.
2077    
2078        (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible).
2079    
2080        (f) \g{name} is another synonym - part of Perl 5.10's unification of
2081            reference syntax.
2082    
2083        (g) (?| introduces a group in which the numbering of parentheses in each
2084            alternative starts with the same number.
2085    
2086        (h) \h, \H, \v, and \V match horizontal and vertical whitespace.
2087    
2088     7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and
2089        PCRE_INFO_JCHANGED.
2090    
2091     8. A pattern such as  (.*(.)?)*  caused pcre_exec() to fail by either not
2092        terminating or by crashing. Diagnosed by Viktor Griph; it was in the code
2093        for detecting groups that can match an empty string.
2094    
2095     9. A pattern with a very large number of alternatives (more than several
2096        hundred) was running out of internal workspace during the pre-compile
2097        phase, where pcre_compile() figures out how much memory will be needed. A
2098        bit of new cunning has reduced the workspace needed for groups with
2099        alternatives. The 1000-alternative test pattern now uses 12 bytes of
2100        workspace instead of running out of the 4096 that are available.
2101    
2102    10. Inserted some missing (unsigned int) casts to get rid of compiler warnings.
2103    
2104    11. Applied patch from Google to remove an optimization that didn't quite work.
2105        The report of the bug said:
2106    
2107          pcrecpp::RE("a*").FullMatch("aaa") matches, while
2108          pcrecpp::RE("a*?").FullMatch("aaa") does not, and
2109          pcrecpp::RE("a*?\\z").FullMatch("aaa") does again.
2110    
2111    12. If \p or \P was used in non-UTF-8 mode on a character greater than 127
2112        it matched the wrong number of bytes.
2113    
2114    
2115    Version 7.1 24-Apr-07
2116  ---------------------  ---------------------
2117    
2118   1. Applied Bob Rossi and Daniel G's patches to convert the build system to one   1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
# Line 33  Version 7.1 12-Mar-07 Line 2144  Version 7.1 12-Mar-07
2144   5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan   5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
2145      Weber: (1) pcre_internal.h was missing some function renames; (2) updated      Weber: (1) pcre_internal.h was missing some function renames; (2) updated
2146      makevp.bat for the current PCRE, using the additional files      makevp.bat for the current PCRE, using the additional files
2147      makevp-c.txt, makevp-l.txt, and pcregexp.pas.      makevp_c.txt, makevp_l.txt, and pcregexp.pas.
2148    
2149   6. A Windows user reported a minor discrepancy with test 2, which turned out   6. A Windows user reported a minor discrepancy with test 2, which turned out
2150      to be caused by a trailing space on an input line that had got lost in his      to be caused by a trailing space on an input line that had got lost in his
# Line 115  Version 7.1 12-Mar-07 Line 2226  Version 7.1 12-Mar-07
2226    
2227  14. If erroroffset was passed as NULL to pcre_compile, it provoked a  14. If erroroffset was passed as NULL to pcre_compile, it provoked a
2228      segmentation fault instead of returning the appropriate error message.      segmentation fault instead of returning the appropriate error message.
2229    
2230  15. In multiline mode when the newline sequence was set to "any", the pattern  15. In multiline mode when the newline sequence was set to "any", the pattern
2231      ^$ would give a match between the \r and \n of a subject such as "A\r\nB".      ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
2232      This doesn't seem right; it now treats the CRLF combination as the line      This doesn't seem right; it now treats the CRLF combination as the line
2233      ending, and so does not match in that case. It's only a pattern such as ^$      ending, and so does not match in that case. It's only a pattern such as ^$
2234      that would hit this one: something like ^ABC$ would have failed after \r      that would hit this one: something like ^ABC$ would have failed after \r
2235      and then tried again after \r\n.      and then tried again after \r\n.
2236    
2237  16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"  16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
2238      in an attempt to make files that differ only in their line terminators      in an attempt to make files that differ only in their line terminators
2239      compare equal. This works on Linux.      compare equal. This works on Linux.
2240    
2241    17. Under certain error circumstances pcregrep might try to free random memory
2242        as it exited. This is now fixed, thanks to valgrind.
2243    
2244    19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
2245        "abc\r\n\r\n", it found an unwanted second match after the second \r. This
2246        was because its rules for how to advance for /g after matching an empty
2247        string at the end of a line did not allow for this case. They now check for
2248        it specially.
2249    
2250    20. pcretest is supposed to handle patterns and data of any length, by
2251        extending its buffers when necessary. It was getting this wrong when the
2252        buffer for a data line had to be extended.
2253    
2254    21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
2255        CRLF as a newline sequence.
2256    
2257    22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
2258        out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
2259        I have nevertheless tidied it up.
2260    
2261    23. Added some casts to kill warnings from HP-UX ia64 compiler.
2262    
2263    24. Added a man page for pcre-config.
2264    
2265    
2266  Version 7.0 19-Dec-06  Version 7.0 19-Dec-06

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