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

Diff of /code/trunk/ChangeLog

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

revision 365 by ph10, Fri Jul 11 17:06:55 2008 UTC revision 720 by ph10, Fri Oct 7 15:18:21 2011 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 8.0 02 Jul-08  Version 8.20 23-Sep-2011
5    ------------------------
6    
7    1.  Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
8        a POSIX class. After further experiments with Perl, which convinced me that
9        Perl has bugs and confusions, a closing square bracket is no longer allowed
10        in a POSIX name. This bug also affected patterns with classes that started
11        with full stops.
12    
13    2.  If a pattern such as /(a)b|ac/ is matched against "ac", there is no
14        captured substring, but while checking the failing first alternative,
15        substring 1 is temporarily captured. If the output vector supplied to
16        pcre_exec() was not big enough for this capture, the yield of the function
17        was still zero ("insufficient space for captured substrings"). This cannot
18        be totally fixed without adding another stack variable, which seems a lot
19        of expense for a edge case. However, I have improved the situation in cases
20        such as /(a)(b)x|abc/ matched against "abc", where the return code
21        indicates that fewer than the maximum number of slots in the ovector have
22        been set.
23    
24    3.  Related to (2) above: when there are more back references in a pattern than
25        slots in the output vector, pcre_exec() uses temporary memory during
26        matching, and copies in the captures as far as possible afterwards. It was
27        using the entire output vector, but this conflicts with the specification
28        that only 2/3 is used for passing back captured substrings. Now it uses
29        only the first 2/3, for compatibility. This is, of course, another edge
30        case.
31    
32    4.  Zoltan Herczeg's just-in-time compiler support has been integrated into the
33        main code base, and can be used by building with --enable-jit. When this is
34        done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
35        runtime --no-jit option is given.
36    
37    5.  When the number of matches in a pcre_dfa_exec() run exactly filled the
38        ovector, the return from the function was zero, implying that there were
39        other matches that did not fit. The correct "exactly full" value is now
40        returned.
41    
42    6.  If a subpattern that was called recursively or as a subroutine contained
43        (*PRUNE) or any other control that caused it to give a non-standard return,
44        invalid errors such as "Error -26 (nested recursion at the same subject
45        position)" or even infinite loops could occur.
46    
47    7.  If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
48        computing the minimum length on reaching *ACCEPT, and so ended up with the
49        wrong value of 1 rather than 0. Further investigation indicates that
50        computing a minimum subject length in the presence of *ACCEPT is difficult
51        (think back references, subroutine calls), and so I have changed the code
52        so that no minimum is registered for a pattern that contains *ACCEPT.
53    
54    8.  If (*THEN) was present in the first (true) branch of a conditional group,
55        it was not handled as intended. [But see 16 below.]
56    
57    9.  Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
58        Sheri Pierce.
59    
60    10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
61        the first byte in a match must be "a".
62    
63    11. Change 17 for 8.13 increased the recursion depth for patterns like
64        /a(?:.)*?a/ drastically. I've improved things by remembering whether a
65        pattern contains any instances of (*THEN). If it does not, the old
66        optimizations are restored. It would be nice to do this on a per-group
67        basis, but at the moment that is not feasible.
68    
69    12. In some environments, the output of pcretest -C is CRLF terminated. This
70        broke RunTest's code that checks for the link size. A single white space
71        after the value is now allowed for.
72    
73    13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
74        For "fr", it uses the Windows-specific input and output files.
75    
76    14. If (*THEN) appeared in a group that was called recursively or as a
77        subroutine, it did not work as intended. [But see next item.]
78    
79    15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
80        pattern fragments (but not containing any | characters). If A and B are
81        matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
82        was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
83        D. In other words, Perl considers parentheses that do not contain any |
84        characters to be part of a surrounding alternative, whereas PCRE was
85        treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
86        differently. PCRE now behaves in the same way as Perl, except in the case
87        of subroutine/recursion calls such as (?1) which have in any case always
88        been different (but PCRE had them first :-).
89    
90    16. Related to 15 above: Perl does not treat the | in a conditional group as
91        creating alternatives. Such a group is treated in the same way as an
92        ordinary group without any | characters when processing (*THEN). PCRE has
93        been changed to match Perl's behaviour.
94    
95    17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
96        RunGrepTest script failed.
97    
98    
99    Version 8.13 16-Aug-2011
100    ------------------------
101    
102    1.  The Unicode data tables have been updated to Unicode 6.0.0.
103    
104    2.  Two minor typos in pcre_internal.h have been fixed.
105    
106    3.  Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
107        pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
108        in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
109    
110    4.  There were a number of related bugs in the code for matching backrefences
111        caselessly in UTF-8 mode when codes for the characters concerned were
112        different numbers of bytes. For example, U+023A and U+2C65 are an upper
113        and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
114        (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
115        code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
116        2-byte code at the end of the subject (it thought there wasn't enough data
117        left).
118    
119    5.  Comprehensive information about what went wrong is now returned by
120        pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
121        as the output vector has at least 2 elements. The offset of the start of
122        the failing character and a reason code are placed in the vector.
123    
124    6.  When the UTF-8 string check fails for pcre_compile(), the offset that is
125        now returned is for the first byte of the failing character, instead of the
126        last byte inspected. This is an incompatible change, but I hope it is small
127        enough not to be a problem. It makes the returned offset consistent with
128        pcre_exec() and pcre_dfa_exec().
129    
130    7.  pcretest now gives a text phrase as well as the error number when
131        pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
132        failure, the offset and reason code are output.
133    
134    8.  When \R was used with a maximizing quantifier it failed to skip backwards
135        over a \r\n pair if the subsequent match failed. Instead, it just skipped
136        back over a single character (\n). This seems wrong (because it treated the
137        two characters as a single entity when going forwards), conflicts with the
138        documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
139        behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
140        has been changed.
141    
142    9.  Some internal refactoring has changed the processing so that the handling
143        of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
144        time (the PCRE_DOTALL option was changed this way some time ago: version
145        7.7 change 16). This has made it possible to abolish the OP_OPT op code,
146        which was always a bit of a fudge. It also means that there is one less
147        argument for the match() function, which reduces its stack requirements
148        slightly. This change also fixes an incompatibility with Perl: the pattern
149        (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
150    
151    10. More internal refactoring has drastically reduced the number of recursive
152        calls to match() for possessively repeated groups such as (abc)++ when
153        using pcre_exec().
154    
155    11. While implementing 10, a number of bugs in the handling of groups were
156        discovered and fixed:
157    
158        (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
159        (a|)*(?1) gave a compile-time internal error.
160        ((a|)+)+  did not notice that the outer group could match an empty string.
161        (^a|^)+   was not marked as anchored.
162        (.*a|.*)+ was not marked as matching at start or after a newline.
163    
164    12. Yet more internal refactoring has removed another argument from the match()
165        function. Special calls to this function are now indicated by setting a
166        value in a variable in the "match data" data block.
167    
168    13. Be more explicit in pcre_study() instead of relying on "default" for
169        opcodes that mean there is no starting character; this means that when new
170        ones are added and accidentally left out of pcre_study(), testing should
171        pick them up.
172    
173    14. The -s option of pcretest has been documented for ages as being an old
174        synonym of -m (show memory usage). I have changed it to mean "force study
175        for every regex", that is, assume /S for every regex. This is similar to -i
176        and -d etc. It's slightly incompatible, but I'm hoping nobody is still
177        using it. It makes it easier to run collections of tests with and without
178        study enabled, and thereby test pcre_study() more easily. All the standard
179        tests are now run with and without -s (but some patterns can be marked as
180        "never study" - see 20 below).
181    
182    15. When (*ACCEPT) was used in a subpattern that was called recursively, the
183        restoration of the capturing data to the outer values was not happening
184        correctly.
185    
186    16. If a recursively called subpattern ended with (*ACCEPT) and matched an
187        empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
188        pattern had matched an empty string, and so incorrectly returned a no
189        match.
190    
191    17. There was optimizing code for the last branch of non-capturing parentheses,
192        and also for the obeyed branch of a conditional subexpression, which used
193        tail recursion to cut down on stack usage. Unfortunately, now that there is
194        the possibility of (*THEN) occurring in these branches, tail recursion is
195        no longer possible because the return has to be checked for (*THEN). These
196        two optimizations have therefore been removed. [But see 8.20/11 above.]
197    
198    18. If a pattern containing \R was studied, it was assumed that \R always
199        matched two bytes, thus causing the minimum subject length to be
200        incorrectly computed because \R can also match just one byte.
201    
202    19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
203        was incorrectly computed.
204    
205    20. If /S is present twice on a test pattern in pcretest input, it now
206        *disables* studying, thereby overriding the use of -s on the command line
207        (see 14 above). This is necessary for one or two tests to keep the output
208        identical in both cases.
209    
210    21. When (*ACCEPT) was used in an assertion that matched an empty string and
211        PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
212    
213    22. When an atomic group that contained a capturing parenthesis was
214        successfully matched, but the branch in which it appeared failed, the
215        capturing was not being forgotten if a higher numbered group was later
216        captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
217        group 1 to "a", when in fact it should be unset. This applied to multi-
218        branched capturing and non-capturing groups, repeated or not, and also to
219        positive assertions (capturing in negative assertions does not happen
220        in PCRE) and also to nested atomic groups.
221    
222    23. Add the ++ qualifier feature to pcretest, to show the remainder of the
223        subject after a captured substring, to make it easier to tell which of a
224        number of identical substrings has been captured.
225    
226    24. The way atomic groups are processed by pcre_exec() has been changed so that
227        if they are repeated, backtracking one repetition now resets captured
228        values correctly. For example, if ((?>(a+)b)+aabab) is matched against
229        "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
230        "aaa". Previously, it would have been "a". As part of this code
231        refactoring, the way recursive calls are handled has also been changed.
232    
233    25. If an assertion condition captured any substrings, they were not passed
234        back unless some other capturing happened later. For example, if
235        (?(?=(a))a) was matched against "a", no capturing was returned.
236    
237    26. When studying a pattern that contained subroutine calls or assertions,
238        the code for finding the minimum length of a possible match was handling
239        direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
240        group 1 called group 2 while simultaneously a separate group 2 called group
241        1). A stack overflow occurred in this case. I have fixed this by limiting
242        the recursion depth to 10.
243    
244    27. Updated RunTest.bat in the distribution to the version supplied by Tom
245        Fortmann. This supports explicit test numbers on the command line, and has
246        argument validation and error reporting.
247    
248    28. An instance of \X with an unlimited repeat could fail if at any point the
249        first character it looked at was a mark character.
250    
251    29. Some minor code refactoring concerning Unicode properties and scripts
252        should reduce the stack requirement of match() slightly.
253    
254    30. Added the '=' option to pcretest to check the setting of unused capturing
255        slots at the end of the pattern, which are documented as being -1, but are
256        not included in the return count.
257    
258    31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
259        compiled something random. Now it gives a compile-time error (as does
260        Perl).
261    
262    32. A *MARK encountered during the processing of a positive assertion is now
263        recorded and passed back (compatible with Perl).
264    
265    33. If --only-matching or --colour was set on a pcregrep call whose pattern
266        had alternative anchored branches, the search for a second match in a line
267        was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
268        matched the line "0102" twice. The same bug affected patterns that started
269        with a backwards assertion. For example /\b01|\b02/ also matched "0102"
270        twice.
271    
272    34. Previously, PCRE did not allow quantification of assertions. However, Perl
273        does, and because of capturing effects, quantifying parenthesized
274        assertions may at times be useful. Quantifiers are now allowed for
275        parenthesized assertions.
276    
277    35. A minor code tidy in pcre_compile() when checking options for \R usage.
278    
279    36. \g was being checked for fancy things in a character class, when it should
280        just be a literal "g".
281    
282    37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
283        appearance of a nested POSIX class supersedes an apparent external class.
284        For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
285        unescaped square brackets may also appear as part of class names. For
286        example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
287        more like Perl. (But see 8.20/1 above.)
288    
289    38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
290        was because it thought it was \N{name}, which is not supported).
291    
292    39. Add minix to OS list not supporting the -S option in pcretest.
293    
294    40. PCRE tries to detect cases of infinite recursion at compile time, but it
295        cannot analyze patterns in sufficient detail to catch mutual recursions
296        such as ((?1))((?2)). There is now a runtime test that gives an error if a
297        subgroup is called recursively as a subpattern for a second time at the
298        same position in the subject string. In previous releases this might have
299        been caught by the recursion limit, or it might have run out of stack.
300    
301    41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
302        happen only once. PCRE was, however incorrectly giving a compile time error
303        "recursive call could loop indefinitely" because it cannot analyze the
304        pattern in sufficient detail. The compile time test no longer happens when
305        PCRE is compiling a conditional subpattern, but actual runaway loops are
306        now caught at runtime (see 40 above).
307    
308    42. It seems that Perl allows any characters other than a closing parenthesis
309        to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
310        has been changed to be the same.
311    
312    43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
313        as not to get warnings when autogen.sh is called. Also changed
314        AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
315    
316    44. To help people who use pcregrep to scan files containing exceedingly long
317        lines, the following changes have been made:
318    
319        (a) The default value of the buffer size parameter has been increased from
320            8K to 20K. (The actual buffer used is three times this size.)
321    
322        (b) The default can be changed by ./configure --with-pcregrep-bufsize when
323            PCRE is built.
324    
325        (c) A --buffer-size=n option has been added to pcregrep, to allow the size
326            to be set at run time.
327    
328        (d) Numerical values in pcregrep options can be followed by K or M, for
329            example --buffer-size=50K.
330    
331        (e) If a line being scanned overflows pcregrep's buffer, an error is now
332            given and the return code is set to 2.
333    
334    45. Add a pointer to the latest mark to the callout data block.
335    
336    46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
337        partial match of an empty string instead of no match. This was specific to
338        the use of ".".
339    
340    47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
341        complete match instead of a partial match. This bug was dependent on both
342        the PCRE_UTF8 and PCRE_DOTALL options being set.
343    
344    48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
345        starting byte set, because \b was not being ignored.
346    
347    
348    Version 8.12 15-Jan-2011
349    ------------------------
350    
351    1.  Fixed some typos in the markup of the man pages, and wrote a script that
352        checks for such things as part of the documentation building process.
353    
354    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
355        --match-limit and --recursion-limit options (added for 8.11). In
356        particular, this made one of the standard tests fail. (The integer value
357        went into the wrong half of a long int.)
358    
359    3.  If the --colour option was given to pcregrep with -v (invert match), it
360        did strange things, either producing crazy output, or crashing. It should,
361        of course, ignore a request for colour when reporting lines that do not
362        match.
363    
364    4.  Another pcregrep bug caused similar problems if --colour was specified with
365        -M (multiline) and the pattern match finished with a line ending.
366    
367    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
368        matched in multiline mode, the following line was shown as part of the
369        match. This seems wrong, so I have changed it.
370    
371    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
372        the check for further matches in the same line (so they could be coloured)
373        to overrun the end of the current line. If another match was found, it was
374        incorrectly shown (and then shown again when found in the next line).
375    
376    7.  If pcregrep was compiled under Windows, there was a reference to the
377        function pcregrep_exit() before it was defined. I am assuming this was
378        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
379        reported by a user. I've moved the definition above the reference.
380    
381    
382    Version 8.11 10-Dec-2010
383    ------------------------
384    
385    1.  (*THEN) was not working properly if there were untried alternatives prior
386        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
387        backtracked to try for "b" instead of moving to the next alternative branch
388        at the same level (in this case, to look for "c"). The Perl documentation
389        is clear that when (*THEN) is backtracked onto, it goes to the "next
390        alternative in the innermost enclosing group".
391    
392    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
393        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
394        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
395        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
396        (*THEN).
397    
398    3.  If \s appeared in a character class, it removed the VT character from
399        the class, even if it had been included by some previous item, for example
400        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
401        of \s, but is part of the POSIX "space" class.)
402    
403    4.  A partial match never returns an empty string (because you can always
404        match an empty string at the end of the subject); however the checking for
405        an empty string was starting at the "start of match" point. This has been
406        changed to the "earliest inspected character" point, because the returned
407        data for a partial match starts at this character. This means that, for
408        example, /(?<=abc)def/ gives a partial match for the subject "abc"
409        (previously it gave "no match").
410    
411    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
412        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
413        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
414        has an implication that the given string is incomplete (because a partial
415        match is preferred over a full match). For this reason, these items now
416        give a partial match in this situation. [Aside: previously, the one case
417        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
418        match rather than a full match, which was wrong by the old rules, but is
419        now correct.]
420    
421    6.  There was a bug in the handling of #-introduced comments, recognized when
422        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
423        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
424        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
425        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
426        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
427        places in pcre_compile().
428    
429    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
430        comments when looking ahead for named forward references to subpatterns,
431        the only newline sequence it recognized was NL. It now handles newlines
432        according to the set newline convention.
433    
434    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
435        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
436        cater for a lack of strerror(). These oversights have been fixed.
437    
438    9.  Added --match-limit and --recursion-limit to pcregrep.
439    
440    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
441    
442    11. When the -o option was used, pcregrep was setting a return code of 1, even
443        when matches were found, and --line-buffered was not being honoured.
444    
445    12. Added an optional parentheses number to the -o and --only-matching options
446        of pcregrep.
447    
448    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
449        can match an empty string. The code to do it in pcretest and pcredemo
450        needed fixing:
451    
452        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
453            only one byte after an empty string match just before CRLF (this case
454            just got forgotten; "any" and "anycrlf" were OK).
455    
456        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
457            mode when an empty string match preceded an ASCII character followed by
458            a non-ASCII character. (The code for advancing by one character rather
459            than one byte was nonsense.)
460    
461        (c) The pcredemo.c sample program did not have any code at all to handle
462            the cases when CRLF is a valid newline sequence.
463    
464    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
465        as a starting offset was within the subject string. There is now a new
466        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
467        negative or greater than the length of the string. In order to test this,
468        pcretest is extended to allow the setting of negative starting offsets.
469    
470    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
471        starting offset points to the beginning of a UTF-8 character was
472        unnecessarily clumsy. I tidied it up.
473    
474    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
475        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
476    
477    17. Nobody had reported that the --include_dir option, which was added in
478        release 7.7 should have been called --include-dir (hyphen, not underscore)
479        for compatibility with GNU grep. I have changed it to --include-dir, but
480        left --include_dir as an undocumented synonym, and the same for
481        --exclude-dir, though that is not available in GNU grep, at least as of
482        release 2.5.4.
483    
484    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
485        characters from a string of bytes) have been redefined so as not to use
486        loops, in order to improve performance in some environments. At the same
487        time, I abstracted some of the common code into auxiliary macros to save
488        repetition (this should not affect the compiled code).
489    
490    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
491        compile-time error is now given if \c is not followed by an ASCII
492        character, that is, a byte less than 128. (In EBCDIC mode, the code is
493        different, and any byte value is allowed.)
494    
495    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
496        START_OPTIMIZE option, which is now allowed at compile time - but just
497        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
498        to pcregrep and other applications that have no direct access to PCRE
499        options. The new /Y option in pcretest sets this option when calling
500        pcre_compile().
501    
502    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
503        back references. Groups containing recursive back references were forced to
504        be atomic by that change, but in the case of named groups, the amount of
505        memory required was incorrectly computed, leading to "Failed: internal
506        error: code overflow". This has been fixed.
507    
508    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
509        pcretest.c, to avoid build problems in some Borland environments.
510    
511    
512    Version 8.10 25-Jun-2010
513    ------------------------
514    
515    1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
516        THEN.
517    
518    2.  (*ACCEPT) was not working when inside an atomic group.
519    
520    3.  Inside a character class, \B is treated as a literal by default, but
521        faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
522        causes the error). The code is unchanged, but I tidied the documentation.
523    
524    4.  Inside a character class, PCRE always treated \R and \X as literals,
525        whereas Perl faults them if its -w option is set. I have changed PCRE so
526        that it faults them when PCRE_EXTRA is set.
527    
528    5.  Added support for \N, which always matches any character other than
529        newline. (It is the same as "." when PCRE_DOTALL is not set.)
530    
531    6.  When compiling pcregrep with newer versions of gcc which may have
532        FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
533        declared with attribute warn_unused_result" were given. Just casting the
534        result to (void) does not stop the warnings; a more elaborate fudge is
535        needed. I've used a macro to implement this.
536    
537    7.  Minor change to pcretest.c to avoid a compiler warning.
538    
539    8.  Added four artifical Unicode properties to help with an option to make
540        \s etc use properties (see next item). The new properties are: Xan
541        (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
542    
543    9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
544        use Unicode properties. (*UCP) at the start of a pattern can be used to set
545        this option. Modified pcretest to add /W to test this facility. Added
546        REG_UCP to make it available via the POSIX interface.
547    
548    10. Added --line-buffered to pcregrep.
549    
550    11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
551        studied, and the match started with a letter with a code point greater than
552        127 whose first byte was different to the first byte of the other case of
553        the letter, the other case of this starting letter was not recognized
554        (#976).
555    
556    12. If a pattern that was studied started with a repeated Unicode property
557        test, for example, \p{Nd}+, there was the theoretical possibility of
558        setting up an incorrect bitmap of starting bytes, but fortunately it could
559        not have actually happened in practice until change 8 above was made (it
560        added property types that matched character-matching opcodes).
561    
562    13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
563        possible starting bytes for non-anchored patterns.
564    
565    14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
566        \R, and also a number of cases that involve Unicode properties, both
567        explicit and implicit when PCRE_UCP is set.
568    
569    15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
570        input, it could crash or give wrong results if characters with values
571        greater than 0xc0 were present in the subject string. (Detail: it assumed
572        UTF-8 input when processing these items.)
573    
574    16. Added a lot of (int) casts to avoid compiler warnings in systems where
575        size_t is 64-bit (#991).
576    
577    17. Added a check for running out of memory when PCRE is compiled with
578        --disable-stack-for-recursion (#990).
579    
580    18. If the last data line in a file for pcretest does not have a newline on
581        the end, a newline was missing in the output.
582    
583    19. The default pcre_chartables.c file recognizes only ASCII characters (values
584        less than 128) in its various bitmaps. However, there is a facility for
585        generating tables according to the current locale when PCRE is compiled. It
586        turns out that in some environments, 0x85 and 0xa0, which are Unicode space
587        characters, are recognized by isspace() and therefore were getting set in
588        these tables, and indeed these tables seem to approximate to ISO 8859. This
589        caused a problem in UTF-8 mode when pcre_study() was used to create a list
590        of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
591        which of course cannot start UTF-8 characters. I have changed the code so
592        that only real ASCII characters (less than 128) and the correct starting
593        bytes for UTF-8 encodings are set for characters greater than 127 when in
594        UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
595        altogether.)
596    
597    20. Added the /T option to pcretest so as to be able to run tests with non-
598        standard character tables, thus making it possible to include the tests
599        used for 19 above in the standard set of tests.
600    
601    21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
602        reference to a subpattern the other side of a comment that contains an
603        opening parenthesis caused either an internal compiling error, or a
604        reference to the wrong subpattern.
605    
606    
607    Version 8.02 19-Mar-2010
608    ------------------------
609    
610    1.  The Unicode data tables have been updated to Unicode 5.2.0.
611    
612    2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
613        configured.
614    
615    3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
616        original author of that file, following a query about its status.
617    
618    4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
619        inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
620    
621    5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
622        quantifier applied to a forward-referencing subroutine call, could compile
623        incorrect code or give the error "internal error: previously-checked
624        referenced subpattern not found".
625    
626    6.  Both MS Visual Studio and Symbian OS have problems with initializing
627        variables to point to external functions. For these systems, therefore,
628        pcre_malloc etc. are now initialized to local functions that call the
629        relevant global functions.
630    
631    7.  There were two entries missing in the vectors called coptable and poptable
632        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
633        I've fixed the data, and added a kludgy way of testing at compile time that
634        the lengths are correct (equal to the number of opcodes).
635    
636    8.  Following on from 7, I added a similar kludge to check the length of the
637        eint vector in pcreposix.c.
638    
639    9.  Error texts for pcre_compile() are held as one long string to avoid too
640        much relocation at load time. To find a text, the string is searched,
641        counting zeros. There was no check for running off the end of the string,
642        which could happen if a new error number was added without updating the
643        string.
644    
645    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
646    
647    11. \K was not working if it appeared in an atomic group or in a group that
648        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
649        \K is "not well defined" if used in an assertion. PCRE now accepts it if
650        the assertion is positive, but not if it is negative.
651    
652    12. Change 11 fortuitously reduced the size of the stack frame used in the
653        "match()" function of pcre_exec.c by one pointer. Forthcoming
654        implementation of support for (*MARK) will need an extra pointer on the
655        stack; I have reserved it now, so that the stack frame size does not
656        decrease.
657    
658    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
659        item in branch that calls a recursion is a subroutine call - as in the
660        second branch in the above example - was incorrectly given the compile-
661        time error "recursive call could loop indefinitely" because pcre_compile()
662        was not correctly checking the subroutine for matching a non-empty string.
663    
664    14. The checks for overrunning compiling workspace could trigger after an
665        overrun had occurred. This is a "should never occur" error, but it can be
666        triggered by pathological patterns such as hundreds of nested parentheses.
667        The checks now trigger 100 bytes before the end of the workspace.
668    
669    15. Fix typo in configure.ac: "srtoq" should be "strtoq".
670    
671    
672    Version 8.01 19-Jan-2010
673    ------------------------
674    
675    1.  If a pattern contained a conditional subpattern with only one branch (in
676        particular, this includes all (*DEFINE) patterns), a call to pcre_study()
677        computed the wrong minimum data length (which is of course zero for such
678        subpatterns). This could cause incorrect "no match" results.
679    
680    2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
681        the pattern is reset in the first branch, pcre_compile() failed with
682        "internal error: code overflow at offset...". This happened only when
683        the reset was to the original external option setting. (An optimization
684        abstracts leading options settings into an external setting, which was the
685        cause of this.)
686    
687    3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
688        of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
689        assertion pattern did not match (meaning that the assertion was true), it
690        was incorrectly treated as false if the SKIP had been reached during the
691        matching. This also applied to assertions used as conditions.
692    
693    4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
694        assertion subpattern, including such a pattern used as a condition,
695        unpredictable results occurred, instead of the error return
696        PCRE_ERROR_DFA_UITEM.
697    
698    5.  The C++ GlobalReplace function was not working like Perl for the special
699        situation when an empty string is matched. It now does the fancy magic
700        stuff that is necessary.
701    
702    6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
703        removed. (These were left over from very, very early versions of PCRE.)
704    
705    7.  Some cosmetic changes to the code to make life easier when compiling it
706        as part of something else:
707    
708        (a) Change DEBUG to PCRE_DEBUG.
709    
710        (b) In pcre_compile(), rename the member of the "branch_chain" structure
711            called "current" as "current_branch", to prevent a collision with the
712            Linux macro when compiled as a kernel module.
713    
714        (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
715            prevent a collision with the Linux macro when compiled as a kernel
716            module.
717    
718    8.  In pcre_compile() there are some checks for integer overflows that used to
719        cast potentially large values to (double). This has been changed to that
720        when building, a check for int64_t is made, and if it is found, it is used
721        instead, thus avoiding the use of floating point arithmetic. (There is no
722        other use of FP in PCRE.) If int64_t is not found, the fallback is to
723        double.
724    
725    9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
726        2005 (difference between two addresses compared to an unsigned value).
727    
728    10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
729        custom one, because of the following reported problem in Windows:
730    
731          - libbz2 uses the Pascal calling convention (WINAPI) for the functions
732              under Win32.
733          - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
734              therefore missing the function definition.
735          - The compiler thus generates a "C" signature for the test function.
736          - The linker fails to find the "C" function.
737          - PCRE fails to configure if asked to do so against libbz2.
738    
739    11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
740        messages were output:
741    
742          Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
743          rerunning libtoolize, to keep the correct libtool macros in-tree.
744          Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
745    
746        I have done both of these things.
747    
748    12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
749        most of the time, it *can* run out if it is given a pattern that contains a
750        runaway infinite recursion. I updated the discussion in the pcrestack man
751        page.
752    
753    13. Now that we have gone to the x.xx style of version numbers, the minor
754        version may start with zero. Using 08 or 09 is a bad idea because users
755        might check the value of PCRE_MINOR in their code, and 08 or 09 may be
756        interpreted as invalid octal numbers. I've updated the previous comment in
757        configure.ac, and also added a check that gives an error if 08 or 09 are
758        used.
759    
760    14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
761        causing partial matching to fail when the end of the subject matched \W
762        in a UTF-8 pattern where \W was quantified with a minimum of 3.
763    
764    15. There were some discrepancies between the declarations in pcre_internal.h
765        of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
766        their definitions. The declarations used "const uschar *" and the
767        definitions used USPTR. Even though USPTR is normally defined as "const
768        unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
769        reported that: "This difference in casting confuses some C++ compilers, for
770        example, SunCC recognizes above declarations as different functions and
771        generates broken code for hbpcre." I have changed the declarations to use
772        USPTR.
773    
774    16. GNU libtool is named differently on some systems. The autogen.sh script now
775        tries several variants such as glibtoolize (MacOSX) and libtoolize1x
776        (FreeBSD).
777    
778    17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
779        (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
780        comment: "Figure out how to create a longlong from a string: strtoll and
781        equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
782        instance, but it only takes 2 args instead of 3!"
783    
784    18. A subtle bug concerned with back references has been fixed by a change of
785        specification, with a corresponding code fix. A pattern such as
786        ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
787        refers, was giving matches when it shouldn't. For example, xa=xaaa would
788        match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
789        same bug. Such groups have to be quantified to be useful, or contained
790        inside another quantified group. (If there's no repetition, the reference
791        can never match.) The problem arises because, having left the group and
792        moved on to the rest of the pattern, a later failure that backtracks into
793        the group uses the captured value from the final iteration of the group
794        rather than the correct earlier one. I have fixed this in PCRE by forcing
795        any group that contains a reference to itself to be an atomic group; that
796        is, there cannot be any backtracking into it once it has completed. This is
797        similar to recursive and subroutine calls.
798    
799    
800    Version 8.00 19-Oct-09
801    ----------------------
802    
803    1.  The table for translating pcre_compile() error codes into POSIX error codes
804        was out-of-date, and there was no check on the pcre_compile() error code
805        being within the table. This could lead to an OK return being given in
806        error.
807    
808    2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
809        "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
810        in a Windows environment.
811    
812    3.  The pcregrep --count option prints the count for each file even when it is
813        zero, as does GNU grep. However, pcregrep was also printing all files when
814        --files-with-matches was added. Now, when both options are given, it prints
815        counts only for those files that have at least one match. (GNU grep just
816        prints the file name in this circumstance, but including the count seems
817        more useful - otherwise, why use --count?) Also ensured that the
818        combination -clh just lists non-zero counts, with no names.
819    
820    4.  The long form of the pcregrep -F option was incorrectly implemented as
821        --fixed_strings instead of --fixed-strings. This is an incompatible change,
822        but it seems right to fix it, and I didn't think it was worth preserving
823        the old behaviour.
824    
825    5.  The command line items --regex=pattern and --regexp=pattern were not
826        recognized by pcregrep, which required --regex pattern or --regexp pattern
827        (with a space rather than an '='). The man page documented the '=' forms,
828        which are compatible with GNU grep; these now work.
829    
830    6.  No libpcreposix.pc file was created for pkg-config; there was just
831        libpcre.pc and libpcrecpp.pc. The omission has been rectified.
832    
833    7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
834        when UCP support is not needed, by modifying the Python script that
835        generates it from Unicode data files. This should not matter if the module
836        is correctly used as a library, but I received one complaint about 50K of
837        unwanted data. My guess is that the person linked everything into his
838        program rather than using a library. Anyway, it does no harm.
839    
840    8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
841        was a minimum greater than 1 for a wide character in a possessive
842        repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
843        which had an unlimited repeat of a nested, fixed maximum repeat of a wide
844        character. Chaos in the form of incorrect output or a compiling loop could
845        result.
846    
847    9.  The restrictions on what a pattern can contain when partial matching is
848        requested for pcre_exec() have been removed. All patterns can now be
849        partially matched by this function. In addition, if there are at least two
850        slots in the offset vector, the offset of the earliest inspected character
851        for the match and the offset of the end of the subject are set in them when
852        PCRE_ERROR_PARTIAL is returned.
853    
854    10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
855        synonymous with PCRE_PARTIAL, for backwards compatibility, and
856        PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
857        and may be more useful for multi-segment matching.
858    
859    11. Partial matching with pcre_exec() is now more intuitive. A partial match
860        used to be given if ever the end of the subject was reached; now it is
861        given only if matching could not proceed because another character was
862        needed. This makes a difference in some odd cases such as Z(*FAIL) with the
863        string "Z", which now yields "no match" instead of "partial match". In the
864        case of pcre_dfa_exec(), "no match" is given if every matching path for the
865        final character ended with (*FAIL).
866    
867    12. Restarting a match using pcre_dfa_exec() after a partial match did not work
868        if the pattern had a "must contain" character that was already found in the
869        earlier partial match, unless partial matching was again requested. For
870        example, with the pattern /dog.(body)?/, the "must contain" character is
871        "g". If the first part-match was for the string "dog", restarting with
872        "sbody" failed. This bug has been fixed.
873    
874    13. The string returned by pcre_dfa_exec() after a partial match has been
875        changed so that it starts at the first inspected character rather than the
876        first character of the match. This makes a difference only if the pattern
877        starts with a lookbehind assertion or \b or \B (\K is not supported by
878        pcre_dfa_exec()). It's an incompatible change, but it makes the two
879        matching functions compatible, and I think it's the right thing to do.
880    
881    14. Added a pcredemo man page, created automatically from the pcredemo.c file,
882        so that the demonstration program is easily available in environments where
883        PCRE has not been installed from source.
884    
885    15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
886        libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
887        library.
888    
889    16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
890        It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
891        is not the first non-POSIX option to be added. Clearly some people find
892        these options useful.
893    
894    17. If a caller to the POSIX matching function regexec() passes a non-zero
895        value for nmatch with a NULL value for pmatch, the value of
896        nmatch is forced to zero.
897    
898    18. RunGrepTest did not have a test for the availability of the -u option of
899        the diff command, as RunTest does. It now checks in the same way as
900        RunTest, and also checks for the -b option.
901    
902    19. If an odd number of negated classes containing just a single character
903        interposed, within parentheses, between a forward reference to a named
904        subpattern and the definition of the subpattern, compilation crashed with
905        an internal error, complaining that it could not find the referenced
906        subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
907        [The bug was that it was starting one character too far in when skipping
908        over the character class, thus treating the ] as data rather than
909        terminating the class. This meant it could skip too much.]
910    
911    20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
912        /g option in pcretest when the pattern contains \K, which makes it possible
913        to have an empty string match not at the start, even when the pattern is
914        anchored. Updated pcretest and pcredemo to use this option.
915    
916    21. If the maximum number of capturing subpatterns in a recursion was greater
917        than the maximum at the outer level, the higher number was returned, but
918        with unset values at the outer level. The correct (outer level) value is
919        now given.
920    
921    22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
922        PCRE did not set those parentheses (unlike Perl). I have now found a way to
923        make it do so. The string so far is captured, making this feature
924        compatible with Perl.
925    
926    23. The tests have been re-organized, adding tests 11 and 12, to make it
927        possible to check the Perl 5.10 features against Perl 5.10.
928    
929    24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
930        pattern matches a fixed length string. PCRE did not allow this; now it
931        does. Neither allows recursion.
932    
933    25. I finally figured out how to implement a request to provide the minimum
934        length of subject string that was needed in order to match a given pattern.
935        (It was back references and recursion that I had previously got hung up
936        on.) This code has now been added to pcre_study(); it finds a lower bound
937        to the length of subject needed. It is not necessarily the greatest lower
938        bound, but using it to avoid searching strings that are too short does give
939        some useful speed-ups. The value is available to calling programs via
940        pcre_fullinfo().
941    
942    26. While implementing 25, I discovered to my embarrassment that pcretest had
943        not been passing the result of pcre_study() to pcre_dfa_exec(), so the
944        study optimizations had never been tested with that matching function.
945        Oops. What is worse, even when it was passed study data, there was a bug in
946        pcre_dfa_exec() that meant it never actually used it. Double oops. There
947        were also very few tests of studied patterns with pcre_dfa_exec().
948    
949    27. If (?| is used to create subpatterns with duplicate numbers, they are now
950        allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
951        on the other side of the coin, they are no longer allowed to have different
952        names, because these cannot be distinguished in PCRE, and this has caused
953        confusion. (This is a difference from Perl.)
954    
955    28. When duplicate subpattern names are present (necessarily with different
956        numbers, as required by 27 above), and a test is made by name in a
957        conditional pattern, either for a subpattern having been matched, or for
958        recursion in such a pattern, all the associated numbered subpatterns are
959        tested, and the overall condition is true if the condition is true for any
960        one of them. This is the way Perl works, and is also more like the way
961        testing by number works.
962    
963    
964    Version 7.9 11-Apr-09
965    ---------------------
966    
967    1.  When building with support for bzlib/zlib (pcregrep) and/or readline
968        (pcretest), all targets were linked against these libraries. This included
969        libpcre, libpcreposix, and libpcrecpp, even though they do not use these
970        libraries. This caused unwanted dependencies to be created. This problem
971        has been fixed, and now only pcregrep is linked with bzlib/zlib and only
972        pcretest is linked with readline.
973    
974    2.  The "typedef int BOOL" in pcre_internal.h that was included inside the
975        "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
976        moved outside it again, because FALSE and TRUE are already defined in AIX,
977        but BOOL is not.
978    
979    3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
980        PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
981    
982    4.  The pcregrep documentation said spaces were inserted as well as colons (or
983        hyphens) following file names and line numbers when outputting matching
984        lines. This is not true; no spaces are inserted. I have also clarified the
985        wording for the --colour (or --color) option.
986    
987    5.  In pcregrep, when --colour was used with -o, the list of matching strings
988        was not coloured; this is different to GNU grep, so I have changed it to be
989        the same.
990    
991    6.  When --colo(u)r was used in pcregrep, only the first matching substring in
992        each matching line was coloured. Now it goes on to look for further matches
993        of any of the test patterns, which is the same behaviour as GNU grep.
994    
995    7.  A pattern that could match an empty string could cause pcregrep to loop; it
996        doesn't make sense to accept an empty string match in pcregrep, so I have
997        locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
998        seems to be how GNU grep behaves.
999    
1000    8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
1001        start or after a newline", because the conditional assertion was not being
1002        correctly handled. The rule now is that both the assertion and what follows
1003        in the first alternative must satisfy the test.
1004    
1005    9.  If auto-callout was enabled in a pattern with a conditional group whose
1006        condition was an assertion, PCRE could crash during matching, both with
1007        pcre_exec() and pcre_dfa_exec().
1008    
1009    10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
1010        used for matching.
1011    
1012    11. Unicode property support in character classes was not working for
1013        characters (bytes) greater than 127 when not in UTF-8 mode.
1014    
1015    12. Added the -M command line option to pcretest.
1016    
1017    14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
1018    
1019    15. Added the PCRE_NO_START_OPTIMIZE match-time option.
1020    
1021    16. Added comments and documentation about mis-use of no_arg in the C++
1022        wrapper.
1023    
1024    17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
1025        from Martin Jerabek that uses macro names for all relevant character and
1026        string constants.
1027    
1028    18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
1029        SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
1030        SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
1031        these, but not everybody uses configure.
1032    
1033    19. A conditional group that had only one branch was not being correctly
1034        recognized as an item that could match an empty string. This meant that an
1035        enclosing group might also not be so recognized, causing infinite looping
1036        (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
1037        with the subject "ab", where knowledge that the repeated group can match
1038        nothing is needed in order to break the loop.
1039    
1040    20. If a pattern that was compiled with callouts was matched using pcre_dfa_
1041        exec(), but without supplying a callout function, matching went wrong.
1042    
1043    21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
1044        leak if the size of the offset vector was greater than 30. When the vector
1045        is smaller, the saved offsets during recursion go onto a local stack
1046        vector, but for larger vectors malloc() is used. It was failing to free
1047        when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
1048        error, in fact).
1049    
1050    22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
1051        heapframe that is used only when UTF-8 support is enabled. This caused no
1052        problem, but was untidy.
1053    
1054    23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
1055        CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
1056        included within another project.
1057    
1058    24. Steven Van Ingelgem's patches to add more options to the CMake support,
1059        slightly modified by me:
1060    
1061          (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
1062              not building pcregrep.
1063    
1064          (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
1065              if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
1066    
1067    25. Forward references, both numeric and by name, in patterns that made use of
1068        duplicate group numbers, could behave incorrectly or give incorrect errors,
1069        because when scanning forward to find the reference group, PCRE was not
1070        taking into account the duplicate group numbers. A pattern such as
1071        ^X(?3)(a)(?|(b)|(q))(Y) is an example.
1072    
1073    26. Changed a few more instances of "const unsigned char *" to USPTR, making
1074        the feature of a custom pointer more persuasive (as requested by a user).
1075    
1076    27. Wrapped the definitions of fileno and isatty for Windows, which appear in
1077        pcretest.c, inside #ifndefs, because it seems they are sometimes already
1078        pre-defined.
1079    
1080    28. Added support for (*UTF8) at the start of a pattern.
1081    
1082    29. Arrange for flags added by the "release type" setting in CMake to be shown
1083        in the configuration summary.
1084    
1085    
1086    Version 7.8 05-Sep-08
1087  ---------------------  ---------------------
1088    
1089  1.  Replaced UCP searching code with optimized version as implemented for Ad  1.  Replaced UCP searching code with optimized version as implemented for Ad
# Line 31  Version 8.0 02 Jul-08 Line 1113  Version 8.0 02 Jul-08
1113    
1114  7.  Added two (int) casts to pcregrep when printing the difference of two  7.  Added two (int) casts to pcregrep when printing the difference of two
1115      pointers, in case they are 64-bit values.      pointers, in case they are 64-bit values.
1116    
1117  8.  Added comments about Mac OS X stack usage to the pcrestack man page and to  8.  Added comments about Mac OS X stack usage to the pcrestack man page and to
1118      test 2 if it fails.      test 2 if it fails.
1119    
1120  9.  Added PCRE_CALL_CONVENTION just before the names of all exported functions,  9.  Added PCRE_CALL_CONVENTION just before the names of all exported functions,
1121      and a #define of that name to empty if it is not externally set. This is to      and a #define of that name to empty if it is not externally set. This is to
1122      allow users of MSVC to set it if necessary.      allow users of MSVC to set it if necessary.
1123    
1124  10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from  10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
1125      the convenience functions in the pcre_get.c source file.      the convenience functions in the pcre_get.c source file.
1126    
1127  11. An option change at the start of a pattern that had top-level alternatives  11. An option change at the start of a pattern that had top-level alternatives
1128      could cause overwriting and/or a crash. This command provoked a crash in      could cause overwriting and/or a crash. This command provoked a crash in
1129      some environments:      some environments:
1130    
1131        printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest        printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
1132    
1133      This potential security problem was recorded as CVE-2008-2371.      This potential security problem was recorded as CVE-2008-2371.
1134    
1135  12. For a pattern where the match had to start at the beginning or immediately  12. For a pattern where the match had to start at the beginning or immediately
1136      after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and      after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
1137      pcre_dfa_exec() could read past the end of the passed subject if there was      pcre_dfa_exec() could read past the end of the passed subject if there was
1138      no match. To help with detecting such bugs (e.g. with valgrind), I modified      no match. To help with detecting such bugs (e.g. with valgrind), I modified
1139      pcretest so that it places the subject at the end of its malloc-ed buffer.      pcretest so that it places the subject at the end of its malloc-ed buffer.
1140    
1141  13. The change to pcretest in 12 above threw up a couple more cases when pcre_  13. The change to pcretest in 12 above threw up a couple more cases when pcre_
1142      exec() might read past the end of the data buffer in UTF-8 mode.      exec() might read past the end of the data buffer in UTF-8 mode.
1143    
1144  14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and  14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
1145      the data contained the byte 0x85 as part of a UTF-8 character within its      the data contained the byte 0x85 as part of a UTF-8 character within its
1146      first line. This applied both to normal and DFA matching.      first line. This applied both to normal and DFA matching.
1147    
1148    15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
1149        /^[^d]*?$/8 failed to match "abc".
1150    
1151    16. Added a missing copyright notice to pcrecpp_internal.h.
1152    
1153    17. Make it more clear in the documentation that values returned from
1154        pcre_exec() in ovector are byte offsets, not character counts.
1155    
1156    18. Tidied a few places to stop certain compilers from issuing warnings.
1157    
1158    19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
1159        supplied by Stefan Weber. I made a further small update for 7.8 because
1160        there is a change of source arrangements: the pcre_searchfuncs.c module is
1161        replaced by pcre_ucd.c.
1162    
1163    
1164  Version 7.7 07-May-08  Version 7.7 07-May-08

Legend:
Removed from v.365  
changed lines
  Added in v.720

webmaster@exim.org
ViewVC Help
Powered by ViewVC 1.1.12