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

Diff of /code/trunk/ChangeLog

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

revision 412 by ph10, Sat Apr 11 10:34:37 2009 UTC revision 888 by ph10, Tue Jan 17 14:43:23 2012 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4    Version 8.30
5    ------------
6    
7    1.  Renamed "isnumber" as "is_a_number" because in some Mac environments this
8        name is defined in ctype.h.
9    
10    2.  Fixed a bug in fixed-length calculation for lookbehinds that would show up
11        only in quite long subpatterns.
12    
13    3.  Removed the function pcre_info(), which has been obsolete and deprecated
14        since it was replaced by pcre_fullinfo() in February 2000.
15    
16    4.  For a non-anchored pattern, if (*SKIP) was given with a name that did not
17        match a (*MARK), and the match failed at the start of the subject, a
18        reference to memory before the start of the subject could occur. This bug
19        was introduced by fix 17 of release 8.21.
20    
21    5.  A reference to an unset group with zero minimum repetition was giving
22        totally wrong answers (in non-JavaScript-compatibility mode). For example,
23        /(another)?(\1?)test/ matched against "hello world test". This bug was
24        introduced in release 8.13.
25    
26    6.  Add support for 16-bit character strings (a large amount of work involving
27        many changes and refactorings).
28    
29    7.  RunGrepTest failed on msys because \r\n was replaced by whitespace when the
30        command "pattern=`printf 'xxx\r\njkl'`" was run. The pattern is now taken
31        from a file.
32    
33    8.  Ovector size of 2 is also supported by JIT based pcre_exec (the ovector size
34        rounding is not applied in this particular case).
35    
36    9.  The invalid Unicode surrogate codepoints U+D800 to U+DFFF are now rejected
37        if they appear, or are escaped, in patterns.
38    
39    10. Get rid of a number of -Wunused-but-set-variable warnings.
40    
41    11. The pattern /(?=(*:x))(q|)/ matches an empty string, and returns the mark
42        "x". The similar pattern /(?=(*:x))((*:y)q|)/ did not return a mark at all.
43        Oddly, Perl behaves the same way. PCRE has been fixed so that this pattern
44        also returns the mark "x". This bug applied to capturing parentheses,
45        non-capturing parentheses, and atomic parentheses. It also applied to some
46        assertions.
47    
48    12. Stephen Kelly's patch to CMakeLists.txt allows it to parse the version
49        information out of configure.ac instead of relying on pcre.h.generic, which
50        is not stored in the repository.
51    
52    
53    Version 8.21 12-Dec-2011
54    ------------------------
55    
56    1.  Updating the JIT compiler.
57    
58    2.  JIT compiler now supports OP_NCREF, OP_RREF and OP_NRREF. New test cases
59        are added as well.
60    
61    3.  Fix cache-flush issue on PowerPC (It is still an experimental JIT port).
62        PCRE_EXTRA_TABLES is not suported by JIT, and should be checked before
63        calling _pcre_jit_exec. Some extra comments are added.
64    
65    4.  (*MARK) settings inside atomic groups that do not contain any capturing
66        parentheses, for example, (?>a(*:m)), were not being passed out. This bug
67        was introduced by change 18 for 8.20.
68    
69    5.  Supporting of \x, \U and \u in JavaScript compatibility mode based on the
70        ECMA-262 standard.
71    
72    6.  Lookbehinds such as (?<=a{2}b) that contained a fixed repetition were
73        erroneously being rejected as "not fixed length" if PCRE_CASELESS was set.
74        This bug was probably introduced by change 9 of 8.13.
75    
76    7.  While fixing 6 above, I noticed that a number of other items were being
77        incorrectly rejected as "not fixed length". This arose partly because newer
78        opcodes had not been added to the fixed-length checking code. I have (a)
79        corrected the bug and added tests for these items, and (b) arranged for an
80        error to occur if an unknown opcode is encountered while checking for fixed
81        length instead of just assuming "not fixed length". The items that were
82        rejected were: (*ACCEPT), (*COMMIT), (*FAIL), (*MARK), (*PRUNE), (*SKIP),
83        (*THEN), \h, \H, \v, \V, and single character negative classes with fixed
84        repetitions, e.g. [^a]{3}, with and without PCRE_CASELESS.
85    
86    8.  A possessively repeated conditional subpattern such as (?(?=c)c|d)++ was
87        being incorrectly compiled and would have given unpredicatble results.
88    
89    9.  A possessively repeated subpattern with minimum repeat count greater than
90        one behaved incorrectly. For example, (A){2,}+ behaved as if it was
91        (A)(A)++ which meant that, after a subsequent mismatch, backtracking into
92        the first (A) could occur when it should not.
93    
94    10. Add a cast and remove a redundant test from the code.
95    
96    11. JIT should use pcre_malloc/pcre_free for allocation.
97    
98    12. Updated pcre-config so that it no longer shows -L/usr/lib, which seems
99        best practice nowadays, and helps with cross-compiling. (If the exec_prefix
100        is anything other than /usr, -L is still shown).
101    
102    13. In non-UTF-8 mode, \C is now supported in lookbehinds and DFA matching.
103    
104    14. Perl does not support \N without a following name in a [] class; PCRE now
105        also gives an error.
106    
107    15. If a forward reference was repeated with an upper limit of around 2000,
108        it caused the error "internal error: overran compiling workspace". The
109        maximum number of forward references (including repeats) was limited by the
110        internal workspace, and dependent on the LINK_SIZE. The code has been
111        rewritten so that the workspace expands (via pcre_malloc) if necessary, and
112        the default depends on LINK_SIZE. There is a new upper limit (for safety)
113        of around 200,000 forward references. While doing this, I also speeded up
114        the filling in of repeated forward references.
115    
116    16. A repeated forward reference in a pattern such as (a)(?2){2}(.) was
117        incorrectly expecting the subject to contain another "a" after the start.
118    
119    17. When (*SKIP:name) is activated without a corresponding (*MARK:name) earlier
120        in the match, the SKIP should be ignored. This was not happening; instead
121        the SKIP was being treated as NOMATCH. For patterns such as
122        /A(*MARK:A)A+(*SKIP:B)Z|AAC/ this meant that the AAC branch was never
123        tested.
124    
125    18. The behaviour of (*MARK), (*PRUNE), and (*THEN) has been reworked and is
126        now much more compatible with Perl, in particular in cases where the result
127        is a non-match for a non-anchored pattern. For example, if
128        /b(*:m)f|a(*:n)w/ is matched against "abc", the non-match returns the name
129        "m", where previously it did not return a name. A side effect of this
130        change is that for partial matches, the last encountered mark name is
131        returned, as for non matches. A number of tests that were previously not
132        Perl-compatible have been moved into the Perl-compatible test files. The
133        refactoring has had the pleasing side effect of removing one argument from
134        the match() function, thus reducing its stack requirements.
135    
136    19. If the /S+ option was used in pcretest to study a pattern using JIT,
137        subsequent uses of /S (without +) incorrectly behaved like /S+.
138    
139    21. Retrieve executable code size support for the JIT compiler and fixing
140        some warnings.
141    
142    22. A caseless match of a UTF-8 character whose other case uses fewer bytes did
143        not work when the shorter character appeared right at the end of the
144        subject string.
145    
146    23. Added some (int) casts to non-JIT modules to reduce warnings on 64-bit
147        systems.
148    
149    24. Added PCRE_INFO_JITSIZE to pass on the value from (21) above, and also
150        output it when the /M option is used in pcretest.
151    
152    25. The CheckMan script was not being included in the distribution. Also, added
153        an explicit "perl" to run Perl scripts from the PrepareRelease script
154        because this is reportedly needed in Windows.
155    
156    26. If study data was being save in a file and studying had not found a set of
157        "starts with" bytes for the pattern, the data written to the file (though
158        never used) was taken from uninitialized memory and so caused valgrind to
159        complain.
160    
161    27. Updated RunTest.bat as provided by Sheri Pierce.
162    
163    28. Fixed a possible uninitialized memory bug in pcre_jit_compile.c.
164    
165    29. Computation of memory usage for the table of capturing group names was
166        giving an unnecessarily large value.
167    
168    
169    Version 8.20 21-Oct-2011
170    ------------------------
171    
172    1.  Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
173        a POSIX class. After further experiments with Perl, which convinced me that
174        Perl has bugs and confusions, a closing square bracket is no longer allowed
175        in a POSIX name. This bug also affected patterns with classes that started
176        with full stops.
177    
178    2.  If a pattern such as /(a)b|ac/ is matched against "ac", there is no
179        captured substring, but while checking the failing first alternative,
180        substring 1 is temporarily captured. If the output vector supplied to
181        pcre_exec() was not big enough for this capture, the yield of the function
182        was still zero ("insufficient space for captured substrings"). This cannot
183        be totally fixed without adding another stack variable, which seems a lot
184        of expense for a edge case. However, I have improved the situation in cases
185        such as /(a)(b)x|abc/ matched against "abc", where the return code
186        indicates that fewer than the maximum number of slots in the ovector have
187        been set.
188    
189    3.  Related to (2) above: when there are more back references in a pattern than
190        slots in the output vector, pcre_exec() uses temporary memory during
191        matching, and copies in the captures as far as possible afterwards. It was
192        using the entire output vector, but this conflicts with the specification
193        that only 2/3 is used for passing back captured substrings. Now it uses
194        only the first 2/3, for compatibility. This is, of course, another edge
195        case.
196    
197    4.  Zoltan Herczeg's just-in-time compiler support has been integrated into the
198        main code base, and can be used by building with --enable-jit. When this is
199        done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
200        runtime --no-jit option is given.
201    
202    5.  When the number of matches in a pcre_dfa_exec() run exactly filled the
203        ovector, the return from the function was zero, implying that there were
204        other matches that did not fit. The correct "exactly full" value is now
205        returned.
206    
207    6.  If a subpattern that was called recursively or as a subroutine contained
208        (*PRUNE) or any other control that caused it to give a non-standard return,
209        invalid errors such as "Error -26 (nested recursion at the same subject
210        position)" or even infinite loops could occur.
211    
212    7.  If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
213        computing the minimum length on reaching *ACCEPT, and so ended up with the
214        wrong value of 1 rather than 0. Further investigation indicates that
215        computing a minimum subject length in the presence of *ACCEPT is difficult
216        (think back references, subroutine calls), and so I have changed the code
217        so that no minimum is registered for a pattern that contains *ACCEPT.
218    
219    8.  If (*THEN) was present in the first (true) branch of a conditional group,
220        it was not handled as intended. [But see 16 below.]
221    
222    9.  Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
223        Sheri Pierce.
224    
225    10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
226        the first byte in a match must be "a".
227    
228    11. Change 17 for 8.13 increased the recursion depth for patterns like
229        /a(?:.)*?a/ drastically. I've improved things by remembering whether a
230        pattern contains any instances of (*THEN). If it does not, the old
231        optimizations are restored. It would be nice to do this on a per-group
232        basis, but at the moment that is not feasible.
233    
234    12. In some environments, the output of pcretest -C is CRLF terminated. This
235        broke RunTest's code that checks for the link size. A single white space
236        character after the value is now allowed for.
237    
238    13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
239        For "fr", it uses the Windows-specific input and output files.
240    
241    14. If (*THEN) appeared in a group that was called recursively or as a
242        subroutine, it did not work as intended. [But see next item.]
243    
244    15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
245        pattern fragments (but not containing any | characters). If A and B are
246        matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
247        was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
248        D. In other words, Perl considers parentheses that do not contain any |
249        characters to be part of a surrounding alternative, whereas PCRE was
250        treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
251        differently. PCRE now behaves in the same way as Perl, except in the case
252        of subroutine/recursion calls such as (?1) which have in any case always
253        been different (but PCRE had them first :-).
254    
255    16. Related to 15 above: Perl does not treat the | in a conditional group as
256        creating alternatives. Such a group is treated in the same way as an
257        ordinary group without any | characters when processing (*THEN). PCRE has
258        been changed to match Perl's behaviour.
259    
260    17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
261        RunGrepTest script failed.
262    
263    18. Change 22 for version 13 caused atomic groups to use more stack. This is
264        inevitable for groups that contain captures, but it can lead to a lot of
265        stack use in large patterns. The old behaviour has been restored for atomic
266        groups that do not contain any capturing parentheses.
267    
268    19. If the PCRE_NO_START_OPTIMIZE option was set for pcre_compile(), it did not
269        suppress the check for a minimum subject length at run time. (If it was
270        given to pcre_exec() or pcre_dfa_exec() it did work.)
271    
272    20. Fixed an ASCII-dependent infelicity in pcretest that would have made it
273        fail to work when decoding hex characters in data strings in EBCDIC
274        environments.
275    
276    21. It appears that in at least one Mac OS environment, the isxdigit() function
277        is implemented as a macro that evaluates to its argument more than once,
278        contravening the C 90 Standard (I haven't checked a later standard). There
279        was an instance in pcretest which caused it to go wrong when processing
280        \x{...} escapes in subject strings. The has been rewritten to avoid using
281        things like p++ in the argument of isxdigit().
282    
283    
284    Version 8.13 16-Aug-2011
285    ------------------------
286    
287    1.  The Unicode data tables have been updated to Unicode 6.0.0.
288    
289    2.  Two minor typos in pcre_internal.h have been fixed.
290    
291    3.  Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
292        pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
293        in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
294    
295    4.  There were a number of related bugs in the code for matching backrefences
296        caselessly in UTF-8 mode when codes for the characters concerned were
297        different numbers of bytes. For example, U+023A and U+2C65 are an upper
298        and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
299        (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
300        code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
301        2-byte code at the end of the subject (it thought there wasn't enough data
302        left).
303    
304    5.  Comprehensive information about what went wrong is now returned by
305        pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
306        as the output vector has at least 2 elements. The offset of the start of
307        the failing character and a reason code are placed in the vector.
308    
309    6.  When the UTF-8 string check fails for pcre_compile(), the offset that is
310        now returned is for the first byte of the failing character, instead of the
311        last byte inspected. This is an incompatible change, but I hope it is small
312        enough not to be a problem. It makes the returned offset consistent with
313        pcre_exec() and pcre_dfa_exec().
314    
315    7.  pcretest now gives a text phrase as well as the error number when
316        pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
317        failure, the offset and reason code are output.
318    
319    8.  When \R was used with a maximizing quantifier it failed to skip backwards
320        over a \r\n pair if the subsequent match failed. Instead, it just skipped
321        back over a single character (\n). This seems wrong (because it treated the
322        two characters as a single entity when going forwards), conflicts with the
323        documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
324        behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
325        has been changed.
326    
327    9.  Some internal refactoring has changed the processing so that the handling
328        of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
329        time (the PCRE_DOTALL option was changed this way some time ago: version
330        7.7 change 16). This has made it possible to abolish the OP_OPT op code,
331        which was always a bit of a fudge. It also means that there is one less
332        argument for the match() function, which reduces its stack requirements
333        slightly. This change also fixes an incompatibility with Perl: the pattern
334        (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
335    
336    10. More internal refactoring has drastically reduced the number of recursive
337        calls to match() for possessively repeated groups such as (abc)++ when
338        using pcre_exec().
339    
340    11. While implementing 10, a number of bugs in the handling of groups were
341        discovered and fixed:
342    
343        (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
344        (a|)*(?1) gave a compile-time internal error.
345        ((a|)+)+  did not notice that the outer group could match an empty string.
346        (^a|^)+   was not marked as anchored.
347        (.*a|.*)+ was not marked as matching at start or after a newline.
348    
349    12. Yet more internal refactoring has removed another argument from the match()
350        function. Special calls to this function are now indicated by setting a
351        value in a variable in the "match data" data block.
352    
353    13. Be more explicit in pcre_study() instead of relying on "default" for
354        opcodes that mean there is no starting character; this means that when new
355        ones are added and accidentally left out of pcre_study(), testing should
356        pick them up.
357    
358    14. The -s option of pcretest has been documented for ages as being an old
359        synonym of -m (show memory usage). I have changed it to mean "force study
360        for every regex", that is, assume /S for every regex. This is similar to -i
361        and -d etc. It's slightly incompatible, but I'm hoping nobody is still
362        using it. It makes it easier to run collections of tests with and without
363        study enabled, and thereby test pcre_study() more easily. All the standard
364        tests are now run with and without -s (but some patterns can be marked as
365        "never study" - see 20 below).
366    
367    15. When (*ACCEPT) was used in a subpattern that was called recursively, the
368        restoration of the capturing data to the outer values was not happening
369        correctly.
370    
371    16. If a recursively called subpattern ended with (*ACCEPT) and matched an
372        empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
373        pattern had matched an empty string, and so incorrectly returned a no
374        match.
375    
376    17. There was optimizing code for the last branch of non-capturing parentheses,
377        and also for the obeyed branch of a conditional subexpression, which used
378        tail recursion to cut down on stack usage. Unfortunately, now that there is
379        the possibility of (*THEN) occurring in these branches, tail recursion is
380        no longer possible because the return has to be checked for (*THEN). These
381        two optimizations have therefore been removed. [But see 8.20/11 above.]
382    
383    18. If a pattern containing \R was studied, it was assumed that \R always
384        matched two bytes, thus causing the minimum subject length to be
385        incorrectly computed because \R can also match just one byte.
386    
387    19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
388        was incorrectly computed.
389    
390    20. If /S is present twice on a test pattern in pcretest input, it now
391        *disables* studying, thereby overriding the use of -s on the command line
392        (see 14 above). This is necessary for one or two tests to keep the output
393        identical in both cases.
394    
395    21. When (*ACCEPT) was used in an assertion that matched an empty string and
396        PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
397    
398    22. When an atomic group that contained a capturing parenthesis was
399        successfully matched, but the branch in which it appeared failed, the
400        capturing was not being forgotten if a higher numbered group was later
401        captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
402        group 1 to "a", when in fact it should be unset. This applied to multi-
403        branched capturing and non-capturing groups, repeated or not, and also to
404        positive assertions (capturing in negative assertions does not happen
405        in PCRE) and also to nested atomic groups.
406    
407    23. Add the ++ qualifier feature to pcretest, to show the remainder of the
408        subject after a captured substring, to make it easier to tell which of a
409        number of identical substrings has been captured.
410    
411    24. The way atomic groups are processed by pcre_exec() has been changed so that
412        if they are repeated, backtracking one repetition now resets captured
413        values correctly. For example, if ((?>(a+)b)+aabab) is matched against
414        "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
415        "aaa". Previously, it would have been "a". As part of this code
416        refactoring, the way recursive calls are handled has also been changed.
417    
418    25. If an assertion condition captured any substrings, they were not passed
419        back unless some other capturing happened later. For example, if
420        (?(?=(a))a) was matched against "a", no capturing was returned.
421    
422    26. When studying a pattern that contained subroutine calls or assertions,
423        the code for finding the minimum length of a possible match was handling
424        direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
425        group 1 called group 2 while simultaneously a separate group 2 called group
426        1). A stack overflow occurred in this case. I have fixed this by limiting
427        the recursion depth to 10.
428    
429    27. Updated RunTest.bat in the distribution to the version supplied by Tom
430        Fortmann. This supports explicit test numbers on the command line, and has
431        argument validation and error reporting.
432    
433    28. An instance of \X with an unlimited repeat could fail if at any point the
434        first character it looked at was a mark character.
435    
436    29. Some minor code refactoring concerning Unicode properties and scripts
437        should reduce the stack requirement of match() slightly.
438    
439    30. Added the '=' option to pcretest to check the setting of unused capturing
440        slots at the end of the pattern, which are documented as being -1, but are
441        not included in the return count.
442    
443    31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
444        compiled something random. Now it gives a compile-time error (as does
445        Perl).
446    
447    32. A *MARK encountered during the processing of a positive assertion is now
448        recorded and passed back (compatible with Perl).
449    
450    33. If --only-matching or --colour was set on a pcregrep call whose pattern
451        had alternative anchored branches, the search for a second match in a line
452        was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
453        matched the line "0102" twice. The same bug affected patterns that started
454        with a backwards assertion. For example /\b01|\b02/ also matched "0102"
455        twice.
456    
457    34. Previously, PCRE did not allow quantification of assertions. However, Perl
458        does, and because of capturing effects, quantifying parenthesized
459        assertions may at times be useful. Quantifiers are now allowed for
460        parenthesized assertions.
461    
462    35. A minor code tidy in pcre_compile() when checking options for \R usage.
463    
464    36. \g was being checked for fancy things in a character class, when it should
465        just be a literal "g".
466    
467    37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
468        appearance of a nested POSIX class supersedes an apparent external class.
469        For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
470        unescaped square brackets may also appear as part of class names. For
471        example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
472        more like Perl. (But see 8.20/1 above.)
473    
474    38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
475        was because it thought it was \N{name}, which is not supported).
476    
477    39. Add minix to OS list not supporting the -S option in pcretest.
478    
479    40. PCRE tries to detect cases of infinite recursion at compile time, but it
480        cannot analyze patterns in sufficient detail to catch mutual recursions
481        such as ((?1))((?2)). There is now a runtime test that gives an error if a
482        subgroup is called recursively as a subpattern for a second time at the
483        same position in the subject string. In previous releases this might have
484        been caught by the recursion limit, or it might have run out of stack.
485    
486    41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
487        happen only once. PCRE was, however incorrectly giving a compile time error
488        "recursive call could loop indefinitely" because it cannot analyze the
489        pattern in sufficient detail. The compile time test no longer happens when
490        PCRE is compiling a conditional subpattern, but actual runaway loops are
491        now caught at runtime (see 40 above).
492    
493    42. It seems that Perl allows any characters other than a closing parenthesis
494        to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
495        has been changed to be the same.
496    
497    43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
498        as not to get warnings when autogen.sh is called. Also changed
499        AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
500    
501    44. To help people who use pcregrep to scan files containing exceedingly long
502        lines, the following changes have been made:
503    
504        (a) The default value of the buffer size parameter has been increased from
505            8K to 20K. (The actual buffer used is three times this size.)
506    
507        (b) The default can be changed by ./configure --with-pcregrep-bufsize when
508            PCRE is built.
509    
510        (c) A --buffer-size=n option has been added to pcregrep, to allow the size
511            to be set at run time.
512    
513        (d) Numerical values in pcregrep options can be followed by K or M, for
514            example --buffer-size=50K.
515    
516        (e) If a line being scanned overflows pcregrep's buffer, an error is now
517            given and the return code is set to 2.
518    
519    45. Add a pointer to the latest mark to the callout data block.
520    
521    46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
522        partial match of an empty string instead of no match. This was specific to
523        the use of ".".
524    
525    47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
526        complete match instead of a partial match. This bug was dependent on both
527        the PCRE_UTF8 and PCRE_DOTALL options being set.
528    
529    48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
530        starting byte set, because \b was not being ignored.
531    
532    
533    Version 8.12 15-Jan-2011
534    ------------------------
535    
536    1.  Fixed some typos in the markup of the man pages, and wrote a script that
537        checks for such things as part of the documentation building process.
538    
539    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
540        --match-limit and --recursion-limit options (added for 8.11). In
541        particular, this made one of the standard tests fail. (The integer value
542        went into the wrong half of a long int.)
543    
544    3.  If the --colour option was given to pcregrep with -v (invert match), it
545        did strange things, either producing crazy output, or crashing. It should,
546        of course, ignore a request for colour when reporting lines that do not
547        match.
548    
549    4.  Another pcregrep bug caused similar problems if --colour was specified with
550        -M (multiline) and the pattern match finished with a line ending.
551    
552    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
553        matched in multiline mode, the following line was shown as part of the
554        match. This seems wrong, so I have changed it.
555    
556    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
557        the check for further matches in the same line (so they could be coloured)
558        to overrun the end of the current line. If another match was found, it was
559        incorrectly shown (and then shown again when found in the next line).
560    
561    7.  If pcregrep was compiled under Windows, there was a reference to the
562        function pcregrep_exit() before it was defined. I am assuming this was
563        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
564        reported by a user. I've moved the definition above the reference.
565    
566    
567    Version 8.11 10-Dec-2010
568    ------------------------
569    
570    1.  (*THEN) was not working properly if there were untried alternatives prior
571        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
572        backtracked to try for "b" instead of moving to the next alternative branch
573        at the same level (in this case, to look for "c"). The Perl documentation
574        is clear that when (*THEN) is backtracked onto, it goes to the "next
575        alternative in the innermost enclosing group".
576    
577    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
578        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
579        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
580        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
581        (*THEN).
582    
583    3.  If \s appeared in a character class, it removed the VT character from
584        the class, even if it had been included by some previous item, for example
585        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
586        of \s, but is part of the POSIX "space" class.)
587    
588    4.  A partial match never returns an empty string (because you can always
589        match an empty string at the end of the subject); however the checking for
590        an empty string was starting at the "start of match" point. This has been
591        changed to the "earliest inspected character" point, because the returned
592        data for a partial match starts at this character. This means that, for
593        example, /(?<=abc)def/ gives a partial match for the subject "abc"
594        (previously it gave "no match").
595    
596    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
597        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
598        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
599        has an implication that the given string is incomplete (because a partial
600        match is preferred over a full match). For this reason, these items now
601        give a partial match in this situation. [Aside: previously, the one case
602        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
603        match rather than a full match, which was wrong by the old rules, but is
604        now correct.]
605    
606    6.  There was a bug in the handling of #-introduced comments, recognized when
607        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
608        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
609        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
610        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
611        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
612        places in pcre_compile().
613    
614    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
615        comments when looking ahead for named forward references to subpatterns,
616        the only newline sequence it recognized was NL. It now handles newlines
617        according to the set newline convention.
618    
619    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
620        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
621        cater for a lack of strerror(). These oversights have been fixed.
622    
623    9.  Added --match-limit and --recursion-limit to pcregrep.
624    
625    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
626    
627    11. When the -o option was used, pcregrep was setting a return code of 1, even
628        when matches were found, and --line-buffered was not being honoured.
629    
630    12. Added an optional parentheses number to the -o and --only-matching options
631        of pcregrep.
632    
633    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
634        can match an empty string. The code to do it in pcretest and pcredemo
635        needed fixing:
636    
637        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
638            only one byte after an empty string match just before CRLF (this case
639            just got forgotten; "any" and "anycrlf" were OK).
640    
641        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
642            mode when an empty string match preceded an ASCII character followed by
643            a non-ASCII character. (The code for advancing by one character rather
644            than one byte was nonsense.)
645    
646        (c) The pcredemo.c sample program did not have any code at all to handle
647            the cases when CRLF is a valid newline sequence.
648    
649    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
650        as a starting offset was within the subject string. There is now a new
651        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
652        negative or greater than the length of the string. In order to test this,
653        pcretest is extended to allow the setting of negative starting offsets.
654    
655    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
656        starting offset points to the beginning of a UTF-8 character was
657        unnecessarily clumsy. I tidied it up.
658    
659    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
660        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
661    
662    17. Nobody had reported that the --include_dir option, which was added in
663        release 7.7 should have been called --include-dir (hyphen, not underscore)
664        for compatibility with GNU grep. I have changed it to --include-dir, but
665        left --include_dir as an undocumented synonym, and the same for
666        --exclude-dir, though that is not available in GNU grep, at least as of
667        release 2.5.4.
668    
669    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
670        characters from a string of bytes) have been redefined so as not to use
671        loops, in order to improve performance in some environments. At the same
672        time, I abstracted some of the common code into auxiliary macros to save
673        repetition (this should not affect the compiled code).
674    
675    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
676        compile-time error is now given if \c is not followed by an ASCII
677        character, that is, a byte less than 128. (In EBCDIC mode, the code is
678        different, and any byte value is allowed.)
679    
680    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
681        START_OPTIMIZE option, which is now allowed at compile time - but just
682        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
683        to pcregrep and other applications that have no direct access to PCRE
684        options. The new /Y option in pcretest sets this option when calling
685        pcre_compile().
686    
687    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
688        back references. Groups containing recursive back references were forced to
689        be atomic by that change, but in the case of named groups, the amount of
690        memory required was incorrectly computed, leading to "Failed: internal
691        error: code overflow". This has been fixed.
692    
693    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
694        pcretest.c, to avoid build problems in some Borland environments.
695    
696    
697    Version 8.10 25-Jun-2010
698    ------------------------
699    
700    1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
701        THEN.
702    
703    2.  (*ACCEPT) was not working when inside an atomic group.
704    
705    3.  Inside a character class, \B is treated as a literal by default, but
706        faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
707        causes the error). The code is unchanged, but I tidied the documentation.
708    
709    4.  Inside a character class, PCRE always treated \R and \X as literals,
710        whereas Perl faults them if its -w option is set. I have changed PCRE so
711        that it faults them when PCRE_EXTRA is set.
712    
713    5.  Added support for \N, which always matches any character other than
714        newline. (It is the same as "." when PCRE_DOTALL is not set.)
715    
716    6.  When compiling pcregrep with newer versions of gcc which may have
717        FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
718        declared with attribute warn_unused_result" were given. Just casting the
719        result to (void) does not stop the warnings; a more elaborate fudge is
720        needed. I've used a macro to implement this.
721    
722    7.  Minor change to pcretest.c to avoid a compiler warning.
723    
724    8.  Added four artifical Unicode properties to help with an option to make
725        \s etc use properties (see next item). The new properties are: Xan
726        (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
727    
728    9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
729        use Unicode properties. (*UCP) at the start of a pattern can be used to set
730        this option. Modified pcretest to add /W to test this facility. Added
731        REG_UCP to make it available via the POSIX interface.
732    
733    10. Added --line-buffered to pcregrep.
734    
735    11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
736        studied, and the match started with a letter with a code point greater than
737        127 whose first byte was different to the first byte of the other case of
738        the letter, the other case of this starting letter was not recognized
739        (#976).
740    
741    12. If a pattern that was studied started with a repeated Unicode property
742        test, for example, \p{Nd}+, there was the theoretical possibility of
743        setting up an incorrect bitmap of starting bytes, but fortunately it could
744        not have actually happened in practice until change 8 above was made (it
745        added property types that matched character-matching opcodes).
746    
747    13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
748        possible starting bytes for non-anchored patterns.
749    
750    14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
751        \R, and also a number of cases that involve Unicode properties, both
752        explicit and implicit when PCRE_UCP is set.
753    
754    15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
755        input, it could crash or give wrong results if characters with values
756        greater than 0xc0 were present in the subject string. (Detail: it assumed
757        UTF-8 input when processing these items.)
758    
759    16. Added a lot of (int) casts to avoid compiler warnings in systems where
760        size_t is 64-bit (#991).
761    
762    17. Added a check for running out of memory when PCRE is compiled with
763        --disable-stack-for-recursion (#990).
764    
765    18. If the last data line in a file for pcretest does not have a newline on
766        the end, a newline was missing in the output.
767    
768    19. The default pcre_chartables.c file recognizes only ASCII characters (values
769        less than 128) in its various bitmaps. However, there is a facility for
770        generating tables according to the current locale when PCRE is compiled. It
771        turns out that in some environments, 0x85 and 0xa0, which are Unicode space
772        characters, are recognized by isspace() and therefore were getting set in
773        these tables, and indeed these tables seem to approximate to ISO 8859. This
774        caused a problem in UTF-8 mode when pcre_study() was used to create a list
775        of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
776        which of course cannot start UTF-8 characters. I have changed the code so
777        that only real ASCII characters (less than 128) and the correct starting
778        bytes for UTF-8 encodings are set for characters greater than 127 when in
779        UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
780        altogether.)
781    
782    20. Added the /T option to pcretest so as to be able to run tests with non-
783        standard character tables, thus making it possible to include the tests
784        used for 19 above in the standard set of tests.
785    
786    21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
787        reference to a subpattern the other side of a comment that contains an
788        opening parenthesis caused either an internal compiling error, or a
789        reference to the wrong subpattern.
790    
791    
792    Version 8.02 19-Mar-2010
793    ------------------------
794    
795    1.  The Unicode data tables have been updated to Unicode 5.2.0.
796    
797    2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
798        configured.
799    
800    3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
801        original author of that file, following a query about its status.
802    
803    4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
804        inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
805    
806    5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
807        quantifier applied to a forward-referencing subroutine call, could compile
808        incorrect code or give the error "internal error: previously-checked
809        referenced subpattern not found".
810    
811    6.  Both MS Visual Studio and Symbian OS have problems with initializing
812        variables to point to external functions. For these systems, therefore,
813        pcre_malloc etc. are now initialized to local functions that call the
814        relevant global functions.
815    
816    7.  There were two entries missing in the vectors called coptable and poptable
817        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
818        I've fixed the data, and added a kludgy way of testing at compile time that
819        the lengths are correct (equal to the number of opcodes).
820    
821    8.  Following on from 7, I added a similar kludge to check the length of the
822        eint vector in pcreposix.c.
823    
824    9.  Error texts for pcre_compile() are held as one long string to avoid too
825        much relocation at load time. To find a text, the string is searched,
826        counting zeros. There was no check for running off the end of the string,
827        which could happen if a new error number was added without updating the
828        string.
829    
830    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
831    
832    11. \K was not working if it appeared in an atomic group or in a group that
833        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
834        \K is "not well defined" if used in an assertion. PCRE now accepts it if
835        the assertion is positive, but not if it is negative.
836    
837    12. Change 11 fortuitously reduced the size of the stack frame used in the
838        "match()" function of pcre_exec.c by one pointer. Forthcoming
839        implementation of support for (*MARK) will need an extra pointer on the
840        stack; I have reserved it now, so that the stack frame size does not
841        decrease.
842    
843    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
844        item in branch that calls a recursion is a subroutine call - as in the
845        second branch in the above example - was incorrectly given the compile-
846        time error "recursive call could loop indefinitely" because pcre_compile()
847        was not correctly checking the subroutine for matching a non-empty string.
848    
849    14. The checks for overrunning compiling workspace could trigger after an
850        overrun had occurred. This is a "should never occur" error, but it can be
851        triggered by pathological patterns such as hundreds of nested parentheses.
852        The checks now trigger 100 bytes before the end of the workspace.
853    
854    15. Fix typo in configure.ac: "srtoq" should be "strtoq".
855    
856    
857    Version 8.01 19-Jan-2010
858    ------------------------
859    
860    1.  If a pattern contained a conditional subpattern with only one branch (in
861        particular, this includes all (*DEFINE) patterns), a call to pcre_study()
862        computed the wrong minimum data length (which is of course zero for such
863        subpatterns). This could cause incorrect "no match" results.
864    
865    2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
866        the pattern is reset in the first branch, pcre_compile() failed with
867        "internal error: code overflow at offset...". This happened only when
868        the reset was to the original external option setting. (An optimization
869        abstracts leading options settings into an external setting, which was the
870        cause of this.)
871    
872    3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
873        of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
874        assertion pattern did not match (meaning that the assertion was true), it
875        was incorrectly treated as false if the SKIP had been reached during the
876        matching. This also applied to assertions used as conditions.
877    
878    4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
879        assertion subpattern, including such a pattern used as a condition,
880        unpredictable results occurred, instead of the error return
881        PCRE_ERROR_DFA_UITEM.
882    
883    5.  The C++ GlobalReplace function was not working like Perl for the special
884        situation when an empty string is matched. It now does the fancy magic
885        stuff that is necessary.
886    
887    6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
888        removed. (These were left over from very, very early versions of PCRE.)
889    
890    7.  Some cosmetic changes to the code to make life easier when compiling it
891        as part of something else:
892    
893        (a) Change DEBUG to PCRE_DEBUG.
894    
895        (b) In pcre_compile(), rename the member of the "branch_chain" structure
896            called "current" as "current_branch", to prevent a collision with the
897            Linux macro when compiled as a kernel module.
898    
899        (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
900            prevent a collision with the Linux macro when compiled as a kernel
901            module.
902    
903    8.  In pcre_compile() there are some checks for integer overflows that used to
904        cast potentially large values to (double). This has been changed to that
905        when building, a check for int64_t is made, and if it is found, it is used
906        instead, thus avoiding the use of floating point arithmetic. (There is no
907        other use of FP in PCRE.) If int64_t is not found, the fallback is to
908        double.
909    
910    9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
911        2005 (difference between two addresses compared to an unsigned value).
912    
913    10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
914        custom one, because of the following reported problem in Windows:
915    
916          - libbz2 uses the Pascal calling convention (WINAPI) for the functions
917              under Win32.
918          - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
919              therefore missing the function definition.
920          - The compiler thus generates a "C" signature for the test function.
921          - The linker fails to find the "C" function.
922          - PCRE fails to configure if asked to do so against libbz2.
923    
924    11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
925        messages were output:
926    
927          Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
928          rerunning libtoolize, to keep the correct libtool macros in-tree.
929          Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
930    
931        I have done both of these things.
932    
933    12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
934        most of the time, it *can* run out if it is given a pattern that contains a
935        runaway infinite recursion. I updated the discussion in the pcrestack man
936        page.
937    
938    13. Now that we have gone to the x.xx style of version numbers, the minor
939        version may start with zero. Using 08 or 09 is a bad idea because users
940        might check the value of PCRE_MINOR in their code, and 08 or 09 may be
941        interpreted as invalid octal numbers. I've updated the previous comment in
942        configure.ac, and also added a check that gives an error if 08 or 09 are
943        used.
944    
945    14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
946        causing partial matching to fail when the end of the subject matched \W
947        in a UTF-8 pattern where \W was quantified with a minimum of 3.
948    
949    15. There were some discrepancies between the declarations in pcre_internal.h
950        of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
951        their definitions. The declarations used "const uschar *" and the
952        definitions used USPTR. Even though USPTR is normally defined as "const
953        unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
954        reported that: "This difference in casting confuses some C++ compilers, for
955        example, SunCC recognizes above declarations as different functions and
956        generates broken code for hbpcre." I have changed the declarations to use
957        USPTR.
958    
959    16. GNU libtool is named differently on some systems. The autogen.sh script now
960        tries several variants such as glibtoolize (MacOSX) and libtoolize1x
961        (FreeBSD).
962    
963    17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
964        (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
965        comment: "Figure out how to create a longlong from a string: strtoll and
966        equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
967        instance, but it only takes 2 args instead of 3!"
968    
969    18. A subtle bug concerned with back references has been fixed by a change of
970        specification, with a corresponding code fix. A pattern such as
971        ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
972        refers, was giving matches when it shouldn't. For example, xa=xaaa would
973        match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
974        same bug. Such groups have to be quantified to be useful, or contained
975        inside another quantified group. (If there's no repetition, the reference
976        can never match.) The problem arises because, having left the group and
977        moved on to the rest of the pattern, a later failure that backtracks into
978        the group uses the captured value from the final iteration of the group
979        rather than the correct earlier one. I have fixed this in PCRE by forcing
980        any group that contains a reference to itself to be an atomic group; that
981        is, there cannot be any backtracking into it once it has completed. This is
982        similar to recursive and subroutine calls.
983    
984    
985    Version 8.00 19-Oct-09
986    ----------------------
987    
988    1.  The table for translating pcre_compile() error codes into POSIX error codes
989        was out-of-date, and there was no check on the pcre_compile() error code
990        being within the table. This could lead to an OK return being given in
991        error.
992    
993    2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
994        "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
995        in a Windows environment.
996    
997    3.  The pcregrep --count option prints the count for each file even when it is
998        zero, as does GNU grep. However, pcregrep was also printing all files when
999        --files-with-matches was added. Now, when both options are given, it prints
1000        counts only for those files that have at least one match. (GNU grep just
1001        prints the file name in this circumstance, but including the count seems
1002        more useful - otherwise, why use --count?) Also ensured that the
1003        combination -clh just lists non-zero counts, with no names.
1004    
1005    4.  The long form of the pcregrep -F option was incorrectly implemented as
1006        --fixed_strings instead of --fixed-strings. This is an incompatible change,
1007        but it seems right to fix it, and I didn't think it was worth preserving
1008        the old behaviour.
1009    
1010    5.  The command line items --regex=pattern and --regexp=pattern were not
1011        recognized by pcregrep, which required --regex pattern or --regexp pattern
1012        (with a space rather than an '='). The man page documented the '=' forms,
1013        which are compatible with GNU grep; these now work.
1014    
1015    6.  No libpcreposix.pc file was created for pkg-config; there was just
1016        libpcre.pc and libpcrecpp.pc. The omission has been rectified.
1017    
1018    7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
1019        when UCP support is not needed, by modifying the Python script that
1020        generates it from Unicode data files. This should not matter if the module
1021        is correctly used as a library, but I received one complaint about 50K of
1022        unwanted data. My guess is that the person linked everything into his
1023        program rather than using a library. Anyway, it does no harm.
1024    
1025    8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
1026        was a minimum greater than 1 for a wide character in a possessive
1027        repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
1028        which had an unlimited repeat of a nested, fixed maximum repeat of a wide
1029        character. Chaos in the form of incorrect output or a compiling loop could
1030        result.
1031    
1032    9.  The restrictions on what a pattern can contain when partial matching is
1033        requested for pcre_exec() have been removed. All patterns can now be
1034        partially matched by this function. In addition, if there are at least two
1035        slots in the offset vector, the offset of the earliest inspected character
1036        for the match and the offset of the end of the subject are set in them when
1037        PCRE_ERROR_PARTIAL is returned.
1038    
1039    10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
1040        synonymous with PCRE_PARTIAL, for backwards compatibility, and
1041        PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
1042        and may be more useful for multi-segment matching.
1043    
1044    11. Partial matching with pcre_exec() is now more intuitive. A partial match
1045        used to be given if ever the end of the subject was reached; now it is
1046        given only if matching could not proceed because another character was
1047        needed. This makes a difference in some odd cases such as Z(*FAIL) with the
1048        string "Z", which now yields "no match" instead of "partial match". In the
1049        case of pcre_dfa_exec(), "no match" is given if every matching path for the
1050        final character ended with (*FAIL).
1051    
1052    12. Restarting a match using pcre_dfa_exec() after a partial match did not work
1053        if the pattern had a "must contain" character that was already found in the
1054        earlier partial match, unless partial matching was again requested. For
1055        example, with the pattern /dog.(body)?/, the "must contain" character is
1056        "g". If the first part-match was for the string "dog", restarting with
1057        "sbody" failed. This bug has been fixed.
1058    
1059    13. The string returned by pcre_dfa_exec() after a partial match has been
1060        changed so that it starts at the first inspected character rather than the
1061        first character of the match. This makes a difference only if the pattern
1062        starts with a lookbehind assertion or \b or \B (\K is not supported by
1063        pcre_dfa_exec()). It's an incompatible change, but it makes the two
1064        matching functions compatible, and I think it's the right thing to do.
1065    
1066    14. Added a pcredemo man page, created automatically from the pcredemo.c file,
1067        so that the demonstration program is easily available in environments where
1068        PCRE has not been installed from source.
1069    
1070    15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
1071        libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
1072        library.
1073    
1074    16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
1075        It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
1076        is not the first non-POSIX option to be added. Clearly some people find
1077        these options useful.
1078    
1079    17. If a caller to the POSIX matching function regexec() passes a non-zero
1080        value for nmatch with a NULL value for pmatch, the value of
1081        nmatch is forced to zero.
1082    
1083    18. RunGrepTest did not have a test for the availability of the -u option of
1084        the diff command, as RunTest does. It now checks in the same way as
1085        RunTest, and also checks for the -b option.
1086    
1087    19. If an odd number of negated classes containing just a single character
1088        interposed, within parentheses, between a forward reference to a named
1089        subpattern and the definition of the subpattern, compilation crashed with
1090        an internal error, complaining that it could not find the referenced
1091        subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
1092        [The bug was that it was starting one character too far in when skipping
1093        over the character class, thus treating the ] as data rather than
1094        terminating the class. This meant it could skip too much.]
1095    
1096    20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
1097        /g option in pcretest when the pattern contains \K, which makes it possible
1098        to have an empty string match not at the start, even when the pattern is
1099        anchored. Updated pcretest and pcredemo to use this option.
1100    
1101    21. If the maximum number of capturing subpatterns in a recursion was greater
1102        than the maximum at the outer level, the higher number was returned, but
1103        with unset values at the outer level. The correct (outer level) value is
1104        now given.
1105    
1106    22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
1107        PCRE did not set those parentheses (unlike Perl). I have now found a way to
1108        make it do so. The string so far is captured, making this feature
1109        compatible with Perl.
1110    
1111    23. The tests have been re-organized, adding tests 11 and 12, to make it
1112        possible to check the Perl 5.10 features against Perl 5.10.
1113    
1114    24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
1115        pattern matches a fixed length string. PCRE did not allow this; now it
1116        does. Neither allows recursion.
1117    
1118    25. I finally figured out how to implement a request to provide the minimum
1119        length of subject string that was needed in order to match a given pattern.
1120        (It was back references and recursion that I had previously got hung up
1121        on.) This code has now been added to pcre_study(); it finds a lower bound
1122        to the length of subject needed. It is not necessarily the greatest lower
1123        bound, but using it to avoid searching strings that are too short does give
1124        some useful speed-ups. The value is available to calling programs via
1125        pcre_fullinfo().
1126    
1127    26. While implementing 25, I discovered to my embarrassment that pcretest had
1128        not been passing the result of pcre_study() to pcre_dfa_exec(), so the
1129        study optimizations had never been tested with that matching function.
1130        Oops. What is worse, even when it was passed study data, there was a bug in
1131        pcre_dfa_exec() that meant it never actually used it. Double oops. There
1132        were also very few tests of studied patterns with pcre_dfa_exec().
1133    
1134    27. If (?| is used to create subpatterns with duplicate numbers, they are now
1135        allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
1136        on the other side of the coin, they are no longer allowed to have different
1137        names, because these cannot be distinguished in PCRE, and this has caused
1138        confusion. (This is a difference from Perl.)
1139    
1140    28. When duplicate subpattern names are present (necessarily with different
1141        numbers, as required by 27 above), and a test is made by name in a
1142        conditional pattern, either for a subpattern having been matched, or for
1143        recursion in such a pattern, all the associated numbered subpatterns are
1144        tested, and the overall condition is true if the condition is true for any
1145        one of them. This is the way Perl works, and is also more like the way
1146        testing by number works.
1147    
1148    
1149  Version 7.9 11-Apr-09  Version 7.9 11-Apr-09
1150  ---------------------  ---------------------
1151    
# Line 112  Version 7.9 11-Apr-09 Line 1257  Version 7.9 11-Apr-09
1257    
1258  26. Changed a few more instances of "const unsigned char *" to USPTR, making  26. Changed a few more instances of "const unsigned char *" to USPTR, making
1259      the feature of a custom pointer more persuasive (as requested by a user).      the feature of a custom pointer more persuasive (as requested by a user).
1260    
1261  27. Wrapped the definitions of fileno and isatty for Windows, which appear in  27. Wrapped the definitions of fileno and isatty for Windows, which appear in
1262      pcretest.c, inside #ifndefs, because it seems they are sometimes already      pcretest.c, inside #ifndefs, because it seems they are sometimes already
1263      pre-defined.      pre-defined.
1264    
1265  28. Added support for (*UTF8) at the start of a pattern.  28. Added support for (*UTF8) at the start of a pattern.
1266    
1267    29. Arrange for flags added by the "release type" setting in CMake to be shown
1268        in the configuration summary.
1269    
1270    
1271  Version 7.8 05-Sep-08  Version 7.8 05-Sep-08

Legend:
Removed from v.412  
changed lines
  Added in v.888

webmaster@exim.org
ViewVC Help
Powered by ViewVC 1.1.12