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

Diff of /code/trunk/ChangeLog

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

revision 342 by ph10, Sun Apr 20 17:10:13 2008 UTC revision 608 by ph10, Sun Jun 12 16:25:55 2011 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 7.7 05-Mar-08  Version 8.13 30-Apr-2011
5    ------------------------
6    
7    1.  The Unicode data tables have been updated to Unicode 6.0.0.
8    
9    2.  Two minor typos in pcre_internal.h have been fixed.
10    
11    3.  Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
12        pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
13        in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
14    
15    4.  There were a number of related bugs in the code for matching backrefences
16        caselessly in UTF-8 mode when codes for the characters concerned were
17        different numbers of bytes. For example, U+023A and U+2C65 are an upper
18        and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
19        (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
20        code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
21        2-byte code at the end of the subject (it thought there wasn't enough data
22        left).
23    
24    5.  Comprehensive information about what went wrong is now returned by
25        pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
26        as the output vector has at least 2 elements. The offset of the start of
27        the failing character and a reason code are placed in the vector.
28    
29    6.  When the UTF-8 string check fails for pcre_compile(), the offset that is
30        now returned is for the first byte of the failing character, instead of the
31        last byte inspected. This is an incompatible change, but I hope it is small
32        enough not to be a problem. It makes the returned offset consistent with
33        pcre_exec() and pcre_dfa_exec().
34    
35    7.  pcretest now gives a text phrase as well as the error number when
36        pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
37        failure, the offset and reason code are output.
38    
39    8.  When \R was used with a maximizing quantifier it failed to skip backwards
40        over a \r\n pair if the subsequent match failed. Instead, it just skipped
41        back over a single character (\n). This seems wrong (because it treated the
42        two characters as a single entity when going forwards), conflicts with the
43        documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
44        behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
45        has been changed.
46    
47    9.  Some internal refactoring has changed the processing so that the handling
48        of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
49        time (the PCRE_DOTALL option was changed this way some time ago: version
50        7.7 change 16). This has made it possible to abolish the OP_OPT op code,
51        which was always a bit of a fudge. It also means that there is one less
52        argument for the match() function, which reduces its stack requirements
53        slightly. This change also fixes an incompatibility with Perl: the pattern
54        (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
55    
56    10. More internal refactoring has drastically reduced the number of recursive
57        calls to match() for possessively repeated groups such as (abc)++ when
58        using pcre_exec().
59    
60    11. While implementing 10, a number of bugs in the handling of groups were
61        discovered and fixed:
62    
63        (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
64        (a|)*(?1) gave a compile-time internal error.
65        ((a|)+)+  did not notice that the outer group could match an empty string.
66        (^a|^)+   was not marked as anchored.
67        (.*a|.*)+ was not marked as matching at start or after a newline.
68    
69    12. Yet more internal refactoring has removed another argument from the match()
70        function. Special calls to this function are now indicated by setting a
71        value in a variable in the "match data" data block.
72    
73    13. Be more explicit in pcre_study() instead of relying on "default" for
74        opcodes that mean there is no starting character; this means that when new
75        ones are added and accidentally left out of pcre_study(), testing should
76        pick them up.
77    
78    14. The -s option of pcretest has been documented for ages as being an old
79        synonym of -m (show memory usage). I have changed it to mean "force study
80        for every regex", that is, assume /S for every regex. This is similar to -i
81        and -d etc. It's slightly incompatible, but I'm hoping nobody is still
82        using it. It makes it easier to run collection of tests with study enabled,
83        and thereby test pcre_study() more easily.
84    
85    15. When (*ACCEPT) was used in a subpattern that was called recursively, the
86        restoration of the capturing data to the outer values was not happening
87        correctly.
88    
89    16. If a recursively called subpattern ended with (*ACCEPT) and matched an
90        empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
91        pattern had matched an empty string, and so incorrectly returned a no
92        match.
93    
94    
95    Version 8.12 15-Jan-2011
96    ------------------------
97    
98    1.  Fixed some typos in the markup of the man pages, and wrote a script that
99        checks for such things as part of the documentation building process.
100    
101    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
102        --match-limit and --recursion-limit options (added for 8.11). In
103        particular, this made one of the standard tests fail. (The integer value
104        went into the wrong half of a long int.)
105    
106    3.  If the --colour option was given to pcregrep with -v (invert match), it
107        did strange things, either producing crazy output, or crashing. It should,
108        of course, ignore a request for colour when reporting lines that do not
109        match.
110    
111    4.  Another pcregrep bug caused similar problems if --colour was specified with
112        -M (multiline) and the pattern match finished with a line ending.
113    
114    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
115        matched in multiline mode, the following line was shown as part of the
116        match. This seems wrong, so I have changed it.
117    
118    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
119        the check for further matches in the same line (so they could be coloured)
120        to overrun the end of the current line. If another match was found, it was
121        incorrectly shown (and then shown again when found in the next line).
122    
123    7.  If pcregrep was compiled under Windows, there was a reference to the
124        function pcregrep_exit() before it was defined. I am assuming this was
125        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
126        reported by a user. I've moved the definition above the reference.
127    
128    
129    Version 8.11 10-Dec-2010
130    ------------------------
131    
132    1.  (*THEN) was not working properly if there were untried alternatives prior
133        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
134        backtracked to try for "b" instead of moving to the next alternative branch
135        at the same level (in this case, to look for "c"). The Perl documentation
136        is clear that when (*THEN) is backtracked onto, it goes to the "next
137        alternative in the innermost enclosing group".
138    
139    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
140        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
141        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
142        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
143        (*THEN).
144    
145    3.  If \s appeared in a character class, it removed the VT character from
146        the class, even if it had been included by some previous item, for example
147        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
148        of \s, but is part of the POSIX "space" class.)
149    
150    4.  A partial match never returns an empty string (because you can always
151        match an empty string at the end of the subject); however the checking for
152        an empty string was starting at the "start of match" point. This has been
153        changed to the "earliest inspected character" point, because the returned
154        data for a partial match starts at this character. This means that, for
155        example, /(?<=abc)def/ gives a partial match for the subject "abc"
156        (previously it gave "no match").
157    
158    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
159        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
160        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
161        has an implication that the given string is incomplete (because a partial
162        match is preferred over a full match). For this reason, these items now
163        give a partial match in this situation. [Aside: previously, the one case
164        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
165        match rather than a full match, which was wrong by the old rules, but is
166        now correct.]
167    
168    6.  There was a bug in the handling of #-introduced comments, recognized when
169        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
170        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
171        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
172        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
173        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
174        places in pcre_compile().
175    
176    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
177        comments when looking ahead for named forward references to subpatterns,
178        the only newline sequence it recognized was NL. It now handles newlines
179        according to the set newline convention.
180    
181    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
182        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
183        cater for a lack of strerror(). These oversights have been fixed.
184    
185    9.  Added --match-limit and --recursion-limit to pcregrep.
186    
187    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
188    
189    11. When the -o option was used, pcregrep was setting a return code of 1, even
190        when matches were found, and --line-buffered was not being honoured.
191    
192    12. Added an optional parentheses number to the -o and --only-matching options
193        of pcregrep.
194    
195    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
196        can match an empty string. The code to do it in pcretest and pcredemo
197        needed fixing:
198    
199        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
200            only one byte after an empty string match just before CRLF (this case
201            just got forgotten; "any" and "anycrlf" were OK).
202    
203        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
204            mode when an empty string match preceded an ASCII character followed by
205            a non-ASCII character. (The code for advancing by one character rather
206            than one byte was nonsense.)
207    
208        (c) The pcredemo.c sample program did not have any code at all to handle
209            the cases when CRLF is a valid newline sequence.
210    
211    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
212        as a starting offset was within the subject string. There is now a new
213        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
214        negative or greater than the length of the string. In order to test this,
215        pcretest is extended to allow the setting of negative starting offsets.
216    
217    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
218        starting offset points to the beginning of a UTF-8 character was
219        unnecessarily clumsy. I tidied it up.
220    
221    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
222        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
223    
224    17. Nobody had reported that the --include_dir option, which was added in
225        release 7.7 should have been called --include-dir (hyphen, not underscore)
226        for compatibility with GNU grep. I have changed it to --include-dir, but
227        left --include_dir as an undocumented synonym, and the same for
228        --exclude-dir, though that is not available in GNU grep, at least as of
229        release 2.5.4.
230    
231    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
232        characters from a string of bytes) have been redefined so as not to use
233        loops, in order to improve performance in some environments. At the same
234        time, I abstracted some of the common code into auxiliary macros to save
235        repetition (this should not affect the compiled code).
236    
237    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
238        compile-time error is now given if \c is not followed by an ASCII
239        character, that is, a byte less than 128. (In EBCDIC mode, the code is
240        different, and any byte value is allowed.)
241    
242    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
243        START_OPTIMIZE option, which is now allowed at compile time - but just
244        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
245        to pcregrep and other applications that have no direct access to PCRE
246        options. The new /Y option in pcretest sets this option when calling
247        pcre_compile().
248    
249    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
250        back references. Groups containing recursive back references were forced to
251        be atomic by that change, but in the case of named groups, the amount of
252        memory required was incorrectly computed, leading to "Failed: internal
253        error: code overflow". This has been fixed.
254    
255    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
256        pcretest.c, to avoid build problems in some Borland environments.
257    
258    
259    Version 8.10 25-Jun-2010
260    ------------------------
261    
262    1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
263        THEN.
264    
265    2.  (*ACCEPT) was not working when inside an atomic group.
266    
267    3.  Inside a character class, \B is treated as a literal by default, but
268        faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
269        causes the error). The code is unchanged, but I tidied the documentation.
270    
271    4.  Inside a character class, PCRE always treated \R and \X as literals,
272        whereas Perl faults them if its -w option is set. I have changed PCRE so
273        that it faults them when PCRE_EXTRA is set.
274    
275    5.  Added support for \N, which always matches any character other than
276        newline. (It is the same as "." when PCRE_DOTALL is not set.)
277    
278    6.  When compiling pcregrep with newer versions of gcc which may have
279        FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
280        declared with attribute warn_unused_result" were given. Just casting the
281        result to (void) does not stop the warnings; a more elaborate fudge is
282        needed. I've used a macro to implement this.
283    
284    7.  Minor change to pcretest.c to avoid a compiler warning.
285    
286    8.  Added four artifical Unicode properties to help with an option to make
287        \s etc use properties (see next item). The new properties are: Xan
288        (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
289    
290    9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
291        use Unicode properties. (*UCP) at the start of a pattern can be used to set
292        this option. Modified pcretest to add /W to test this facility. Added
293        REG_UCP to make it available via the POSIX interface.
294    
295    10. Added --line-buffered to pcregrep.
296    
297    11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
298        studied, and the match started with a letter with a code point greater than
299        127 whose first byte was different to the first byte of the other case of
300        the letter, the other case of this starting letter was not recognized
301        (#976).
302    
303    12. If a pattern that was studied started with a repeated Unicode property
304        test, for example, \p{Nd}+, there was the theoretical possibility of
305        setting up an incorrect bitmap of starting bytes, but fortunately it could
306        not have actually happened in practice until change 8 above was made (it
307        added property types that matched character-matching opcodes).
308    
309    13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
310        possible starting bytes for non-anchored patterns.
311    
312    14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
313        \R, and also a number of cases that involve Unicode properties, both
314        explicit and implicit when PCRE_UCP is set.
315    
316    15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
317        input, it could crash or give wrong results if characters with values
318        greater than 0xc0 were present in the subject string. (Detail: it assumed
319        UTF-8 input when processing these items.)
320    
321    16. Added a lot of (int) casts to avoid compiler warnings in systems where
322        size_t is 64-bit (#991).
323    
324    17. Added a check for running out of memory when PCRE is compiled with
325        --disable-stack-for-recursion (#990).
326    
327    18. If the last data line in a file for pcretest does not have a newline on
328        the end, a newline was missing in the output.
329    
330    19. The default pcre_chartables.c file recognizes only ASCII characters (values
331        less than 128) in its various bitmaps. However, there is a facility for
332        generating tables according to the current locale when PCRE is compiled. It
333        turns out that in some environments, 0x85 and 0xa0, which are Unicode space
334        characters, are recognized by isspace() and therefore were getting set in
335        these tables, and indeed these tables seem to approximate to ISO 8859. This
336        caused a problem in UTF-8 mode when pcre_study() was used to create a list
337        of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
338        which of course cannot start UTF-8 characters. I have changed the code so
339        that only real ASCII characters (less than 128) and the correct starting
340        bytes for UTF-8 encodings are set for characters greater than 127 when in
341        UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
342        altogether.)
343    
344    20. Added the /T option to pcretest so as to be able to run tests with non-
345        standard character tables, thus making it possible to include the tests
346        used for 19 above in the standard set of tests.
347    
348    21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
349        reference to a subpattern the other side of a comment that contains an
350        opening parenthesis caused either an internal compiling error, or a
351        reference to the wrong subpattern.
352    
353    
354    Version 8.02 19-Mar-2010
355    ------------------------
356    
357    1.  The Unicode data tables have been updated to Unicode 5.2.0.
358    
359    2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
360        configured.
361    
362    3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
363        original author of that file, following a query about its status.
364    
365    4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
366        inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
367    
368    5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
369        quantifier applied to a forward-referencing subroutine call, could compile
370        incorrect code or give the error "internal error: previously-checked
371        referenced subpattern not found".
372    
373    6.  Both MS Visual Studio and Symbian OS have problems with initializing
374        variables to point to external functions. For these systems, therefore,
375        pcre_malloc etc. are now initialized to local functions that call the
376        relevant global functions.
377    
378    7.  There were two entries missing in the vectors called coptable and poptable
379        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
380        I've fixed the data, and added a kludgy way of testing at compile time that
381        the lengths are correct (equal to the number of opcodes).
382    
383    8.  Following on from 7, I added a similar kludge to check the length of the
384        eint vector in pcreposix.c.
385    
386    9.  Error texts for pcre_compile() are held as one long string to avoid too
387        much relocation at load time. To find a text, the string is searched,
388        counting zeros. There was no check for running off the end of the string,
389        which could happen if a new error number was added without updating the
390        string.
391    
392    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
393    
394    11. \K was not working if it appeared in an atomic group or in a group that
395        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
396        \K is "not well defined" if used in an assertion. PCRE now accepts it if
397        the assertion is positive, but not if it is negative.
398    
399    12. Change 11 fortuitously reduced the size of the stack frame used in the
400        "match()" function of pcre_exec.c by one pointer. Forthcoming
401        implementation of support for (*MARK) will need an extra pointer on the
402        stack; I have reserved it now, so that the stack frame size does not
403        decrease.
404    
405    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
406        item in branch that calls a recursion is a subroutine call - as in the
407        second branch in the above example - was incorrectly given the compile-
408        time error "recursive call could loop indefinitely" because pcre_compile()
409        was not correctly checking the subroutine for matching a non-empty string.
410    
411    14. The checks for overrunning compiling workspace could trigger after an
412        overrun had occurred. This is a "should never occur" error, but it can be
413        triggered by pathological patterns such as hundreds of nested parentheses.
414        The checks now trigger 100 bytes before the end of the workspace.
415    
416    15. Fix typo in configure.ac: "srtoq" should be "strtoq".
417    
418    
419    Version 8.01 19-Jan-2010
420    ------------------------
421    
422    1.  If a pattern contained a conditional subpattern with only one branch (in
423        particular, this includes all (*DEFINE) patterns), a call to pcre_study()
424        computed the wrong minimum data length (which is of course zero for such
425        subpatterns). This could cause incorrect "no match" results.
426    
427    2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
428        the pattern is reset in the first branch, pcre_compile() failed with
429        "internal error: code overflow at offset...". This happened only when
430        the reset was to the original external option setting. (An optimization
431        abstracts leading options settings into an external setting, which was the
432        cause of this.)
433    
434    3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
435        of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
436        assertion pattern did not match (meaning that the assertion was true), it
437        was incorrectly treated as false if the SKIP had been reached during the
438        matching. This also applied to assertions used as conditions.
439    
440    4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
441        assertion subpattern, including such a pattern used as a condition,
442        unpredictable results occurred, instead of the error return
443        PCRE_ERROR_DFA_UITEM.
444    
445    5.  The C++ GlobalReplace function was not working like Perl for the special
446        situation when an empty string is matched. It now does the fancy magic
447        stuff that is necessary.
448    
449    6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
450        removed. (These were left over from very, very early versions of PCRE.)
451    
452    7.  Some cosmetic changes to the code to make life easier when compiling it
453        as part of something else:
454    
455        (a) Change DEBUG to PCRE_DEBUG.
456    
457        (b) In pcre_compile(), rename the member of the "branch_chain" structure
458            called "current" as "current_branch", to prevent a collision with the
459            Linux macro when compiled as a kernel module.
460    
461        (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
462            prevent a collision with the Linux macro when compiled as a kernel
463            module.
464    
465    8.  In pcre_compile() there are some checks for integer overflows that used to
466        cast potentially large values to (double). This has been changed to that
467        when building, a check for int64_t is made, and if it is found, it is used
468        instead, thus avoiding the use of floating point arithmetic. (There is no
469        other use of FP in PCRE.) If int64_t is not found, the fallback is to
470        double.
471    
472    9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
473        2005 (difference between two addresses compared to an unsigned value).
474    
475    10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
476        custom one, because of the following reported problem in Windows:
477    
478          - libbz2 uses the Pascal calling convention (WINAPI) for the functions
479              under Win32.
480          - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
481              therefore missing the function definition.
482          - The compiler thus generates a "C" signature for the test function.
483          - The linker fails to find the "C" function.
484          - PCRE fails to configure if asked to do so against libbz2.
485    
486    11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
487        messages were output:
488    
489          Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
490          rerunning libtoolize, to keep the correct libtool macros in-tree.
491          Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
492    
493        I have done both of these things.
494    
495    12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
496        most of the time, it *can* run out if it is given a pattern that contains a
497        runaway infinite recursion. I updated the discussion in the pcrestack man
498        page.
499    
500    13. Now that we have gone to the x.xx style of version numbers, the minor
501        version may start with zero. Using 08 or 09 is a bad idea because users
502        might check the value of PCRE_MINOR in their code, and 08 or 09 may be
503        interpreted as invalid octal numbers. I've updated the previous comment in
504        configure.ac, and also added a check that gives an error if 08 or 09 are
505        used.
506    
507    14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
508        causing partial matching to fail when the end of the subject matched \W
509        in a UTF-8 pattern where \W was quantified with a minimum of 3.
510    
511    15. There were some discrepancies between the declarations in pcre_internal.h
512        of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
513        their definitions. The declarations used "const uschar *" and the
514        definitions used USPTR. Even though USPTR is normally defined as "const
515        unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
516        reported that: "This difference in casting confuses some C++ compilers, for
517        example, SunCC recognizes above declarations as different functions and
518        generates broken code for hbpcre." I have changed the declarations to use
519        USPTR.
520    
521    16. GNU libtool is named differently on some systems. The autogen.sh script now
522        tries several variants such as glibtoolize (MacOSX) and libtoolize1x
523        (FreeBSD).
524    
525    17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
526        (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
527        comment: "Figure out how to create a longlong from a string: strtoll and
528        equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
529        instance, but it only takes 2 args instead of 3!"
530    
531    18. A subtle bug concerned with back references has been fixed by a change of
532        specification, with a corresponding code fix. A pattern such as
533        ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
534        refers, was giving matches when it shouldn't. For example, xa=xaaa would
535        match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
536        same bug. Such groups have to be quantified to be useful, or contained
537        inside another quantified group. (If there's no repetition, the reference
538        can never match.) The problem arises because, having left the group and
539        moved on to the rest of the pattern, a later failure that backtracks into
540        the group uses the captured value from the final iteration of the group
541        rather than the correct earlier one. I have fixed this in PCRE by forcing
542        any group that contains a reference to itself to be an atomic group; that
543        is, there cannot be any backtracking into it once it has completed. This is
544        similar to recursive and subroutine calls.
545    
546    
547    Version 8.00 19-Oct-09
548    ----------------------
549    
550    1.  The table for translating pcre_compile() error codes into POSIX error codes
551        was out-of-date, and there was no check on the pcre_compile() error code
552        being within the table. This could lead to an OK return being given in
553        error.
554    
555    2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
556        "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
557        in a Windows environment.
558    
559    3.  The pcregrep --count option prints the count for each file even when it is
560        zero, as does GNU grep. However, pcregrep was also printing all files when
561        --files-with-matches was added. Now, when both options are given, it prints
562        counts only for those files that have at least one match. (GNU grep just
563        prints the file name in this circumstance, but including the count seems
564        more useful - otherwise, why use --count?) Also ensured that the
565        combination -clh just lists non-zero counts, with no names.
566    
567    4.  The long form of the pcregrep -F option was incorrectly implemented as
568        --fixed_strings instead of --fixed-strings. This is an incompatible change,
569        but it seems right to fix it, and I didn't think it was worth preserving
570        the old behaviour.
571    
572    5.  The command line items --regex=pattern and --regexp=pattern were not
573        recognized by pcregrep, which required --regex pattern or --regexp pattern
574        (with a space rather than an '='). The man page documented the '=' forms,
575        which are compatible with GNU grep; these now work.
576    
577    6.  No libpcreposix.pc file was created for pkg-config; there was just
578        libpcre.pc and libpcrecpp.pc. The omission has been rectified.
579    
580    7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
581        when UCP support is not needed, by modifying the Python script that
582        generates it from Unicode data files. This should not matter if the module
583        is correctly used as a library, but I received one complaint about 50K of
584        unwanted data. My guess is that the person linked everything into his
585        program rather than using a library. Anyway, it does no harm.
586    
587    8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
588        was a minimum greater than 1 for a wide character in a possessive
589        repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
590        which had an unlimited repeat of a nested, fixed maximum repeat of a wide
591        character. Chaos in the form of incorrect output or a compiling loop could
592        result.
593    
594    9.  The restrictions on what a pattern can contain when partial matching is
595        requested for pcre_exec() have been removed. All patterns can now be
596        partially matched by this function. In addition, if there are at least two
597        slots in the offset vector, the offset of the earliest inspected character
598        for the match and the offset of the end of the subject are set in them when
599        PCRE_ERROR_PARTIAL is returned.
600    
601    10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
602        synonymous with PCRE_PARTIAL, for backwards compatibility, and
603        PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
604        and may be more useful for multi-segment matching.
605    
606    11. Partial matching with pcre_exec() is now more intuitive. A partial match
607        used to be given if ever the end of the subject was reached; now it is
608        given only if matching could not proceed because another character was
609        needed. This makes a difference in some odd cases such as Z(*FAIL) with the
610        string "Z", which now yields "no match" instead of "partial match". In the
611        case of pcre_dfa_exec(), "no match" is given if every matching path for the
612        final character ended with (*FAIL).
613    
614    12. Restarting a match using pcre_dfa_exec() after a partial match did not work
615        if the pattern had a "must contain" character that was already found in the
616        earlier partial match, unless partial matching was again requested. For
617        example, with the pattern /dog.(body)?/, the "must contain" character is
618        "g". If the first part-match was for the string "dog", restarting with
619        "sbody" failed. This bug has been fixed.
620    
621    13. The string returned by pcre_dfa_exec() after a partial match has been
622        changed so that it starts at the first inspected character rather than the
623        first character of the match. This makes a difference only if the pattern
624        starts with a lookbehind assertion or \b or \B (\K is not supported by
625        pcre_dfa_exec()). It's an incompatible change, but it makes the two
626        matching functions compatible, and I think it's the right thing to do.
627    
628    14. Added a pcredemo man page, created automatically from the pcredemo.c file,
629        so that the demonstration program is easily available in environments where
630        PCRE has not been installed from source.
631    
632    15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
633        libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
634        library.
635    
636    16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
637        It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
638        is not the first non-POSIX option to be added. Clearly some people find
639        these options useful.
640    
641    17. If a caller to the POSIX matching function regexec() passes a non-zero
642        value for nmatch with a NULL value for pmatch, the value of
643        nmatch is forced to zero.
644    
645    18. RunGrepTest did not have a test for the availability of the -u option of
646        the diff command, as RunTest does. It now checks in the same way as
647        RunTest, and also checks for the -b option.
648    
649    19. If an odd number of negated classes containing just a single character
650        interposed, within parentheses, between a forward reference to a named
651        subpattern and the definition of the subpattern, compilation crashed with
652        an internal error, complaining that it could not find the referenced
653        subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
654        [The bug was that it was starting one character too far in when skipping
655        over the character class, thus treating the ] as data rather than
656        terminating the class. This meant it could skip too much.]
657    
658    20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
659        /g option in pcretest when the pattern contains \K, which makes it possible
660        to have an empty string match not at the start, even when the pattern is
661        anchored. Updated pcretest and pcredemo to use this option.
662    
663    21. If the maximum number of capturing subpatterns in a recursion was greater
664        than the maximum at the outer level, the higher number was returned, but
665        with unset values at the outer level. The correct (outer level) value is
666        now given.
667    
668    22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
669        PCRE did not set those parentheses (unlike Perl). I have now found a way to
670        make it do so. The string so far is captured, making this feature
671        compatible with Perl.
672    
673    23. The tests have been re-organized, adding tests 11 and 12, to make it
674        possible to check the Perl 5.10 features against Perl 5.10.
675    
676    24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
677        pattern matches a fixed length string. PCRE did not allow this; now it
678        does. Neither allows recursion.
679    
680    25. I finally figured out how to implement a request to provide the minimum
681        length of subject string that was needed in order to match a given pattern.
682        (It was back references and recursion that I had previously got hung up
683        on.) This code has now been added to pcre_study(); it finds a lower bound
684        to the length of subject needed. It is not necessarily the greatest lower
685        bound, but using it to avoid searching strings that are too short does give
686        some useful speed-ups. The value is available to calling programs via
687        pcre_fullinfo().
688    
689    26. While implementing 25, I discovered to my embarrassment that pcretest had
690        not been passing the result of pcre_study() to pcre_dfa_exec(), so the
691        study optimizations had never been tested with that matching function.
692        Oops. What is worse, even when it was passed study data, there was a bug in
693        pcre_dfa_exec() that meant it never actually used it. Double oops. There
694        were also very few tests of studied patterns with pcre_dfa_exec().
695    
696    27. If (?| is used to create subpatterns with duplicate numbers, they are now
697        allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
698        on the other side of the coin, they are no longer allowed to have different
699        names, because these cannot be distinguished in PCRE, and this has caused
700        confusion. (This is a difference from Perl.)
701    
702    28. When duplicate subpattern names are present (necessarily with different
703        numbers, as required by 27 above), and a test is made by name in a
704        conditional pattern, either for a subpattern having been matched, or for
705        recursion in such a pattern, all the associated numbered subpatterns are
706        tested, and the overall condition is true if the condition is true for any
707        one of them. This is the way Perl works, and is also more like the way
708        testing by number works.
709    
710    
711    Version 7.9 11-Apr-09
712    ---------------------
713    
714    1.  When building with support for bzlib/zlib (pcregrep) and/or readline
715        (pcretest), all targets were linked against these libraries. This included
716        libpcre, libpcreposix, and libpcrecpp, even though they do not use these
717        libraries. This caused unwanted dependencies to be created. This problem
718        has been fixed, and now only pcregrep is linked with bzlib/zlib and only
719        pcretest is linked with readline.
720    
721    2.  The "typedef int BOOL" in pcre_internal.h that was included inside the
722        "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
723        moved outside it again, because FALSE and TRUE are already defined in AIX,
724        but BOOL is not.
725    
726    3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
727        PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
728    
729    4.  The pcregrep documentation said spaces were inserted as well as colons (or
730        hyphens) following file names and line numbers when outputting matching
731        lines. This is not true; no spaces are inserted. I have also clarified the
732        wording for the --colour (or --color) option.
733    
734    5.  In pcregrep, when --colour was used with -o, the list of matching strings
735        was not coloured; this is different to GNU grep, so I have changed it to be
736        the same.
737    
738    6.  When --colo(u)r was used in pcregrep, only the first matching substring in
739        each matching line was coloured. Now it goes on to look for further matches
740        of any of the test patterns, which is the same behaviour as GNU grep.
741    
742    7.  A pattern that could match an empty string could cause pcregrep to loop; it
743        doesn't make sense to accept an empty string match in pcregrep, so I have
744        locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
745        seems to be how GNU grep behaves.
746    
747    8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
748        start or after a newline", because the conditional assertion was not being
749        correctly handled. The rule now is that both the assertion and what follows
750        in the first alternative must satisfy the test.
751    
752    9.  If auto-callout was enabled in a pattern with a conditional group whose
753        condition was an assertion, PCRE could crash during matching, both with
754        pcre_exec() and pcre_dfa_exec().
755    
756    10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
757        used for matching.
758    
759    11. Unicode property support in character classes was not working for
760        characters (bytes) greater than 127 when not in UTF-8 mode.
761    
762    12. Added the -M command line option to pcretest.
763    
764    14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
765    
766    15. Added the PCRE_NO_START_OPTIMIZE match-time option.
767    
768    16. Added comments and documentation about mis-use of no_arg in the C++
769        wrapper.
770    
771    17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
772        from Martin Jerabek that uses macro names for all relevant character and
773        string constants.
774    
775    18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
776        SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
777        SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
778        these, but not everybody uses configure.
779    
780    19. A conditional group that had only one branch was not being correctly
781        recognized as an item that could match an empty string. This meant that an
782        enclosing group might also not be so recognized, causing infinite looping
783        (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
784        with the subject "ab", where knowledge that the repeated group can match
785        nothing is needed in order to break the loop.
786    
787    20. If a pattern that was compiled with callouts was matched using pcre_dfa_
788        exec(), but without supplying a callout function, matching went wrong.
789    
790    21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
791        leak if the size of the offset vector was greater than 30. When the vector
792        is smaller, the saved offsets during recursion go onto a local stack
793        vector, but for larger vectors malloc() is used. It was failing to free
794        when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
795        error, in fact).
796    
797    22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
798        heapframe that is used only when UTF-8 support is enabled. This caused no
799        problem, but was untidy.
800    
801    23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
802        CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
803        included within another project.
804    
805    24. Steven Van Ingelgem's patches to add more options to the CMake support,
806        slightly modified by me:
807    
808          (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
809              not building pcregrep.
810    
811          (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
812              if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
813    
814    25. Forward references, both numeric and by name, in patterns that made use of
815        duplicate group numbers, could behave incorrectly or give incorrect errors,
816        because when scanning forward to find the reference group, PCRE was not
817        taking into account the duplicate group numbers. A pattern such as
818        ^X(?3)(a)(?|(b)|(q))(Y) is an example.
819    
820    26. Changed a few more instances of "const unsigned char *" to USPTR, making
821        the feature of a custom pointer more persuasive (as requested by a user).
822    
823    27. Wrapped the definitions of fileno and isatty for Windows, which appear in
824        pcretest.c, inside #ifndefs, because it seems they are sometimes already
825        pre-defined.
826    
827    28. Added support for (*UTF8) at the start of a pattern.
828    
829    29. Arrange for flags added by the "release type" setting in CMake to be shown
830        in the configuration summary.
831    
832    
833    Version 7.8 05-Sep-08
834    ---------------------
835    
836    1.  Replaced UCP searching code with optimized version as implemented for Ad
837        Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
838        stage table and inline lookup instead of a function, giving speed ups of 2
839        to 5 times on some simple patterns that I tested. Permission was given to
840        distribute the MultiStage2.py script that generates the tables (it's not in
841        the tarball, but is in the Subversion repository).
842    
843    2.  Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
844        scripts.
845    
846    3.  Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
847        a group with a zero qualifier. The result of the study could be incorrect,
848        or the function might crash, depending on the pattern.
849    
850    4.  Caseless matching was not working for non-ASCII characters in back
851        references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
852        It now works when Unicode Property Support is available.
853    
854    5.  In pcretest, an escape such as \x{de} in the data was always generating
855        a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
856        non-UTF-8 mode. If the value is greater than 255, it gives a warning about
857        truncation.
858    
859    6.  Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
860    
861    7.  Added two (int) casts to pcregrep when printing the difference of two
862        pointers, in case they are 64-bit values.
863    
864    8.  Added comments about Mac OS X stack usage to the pcrestack man page and to
865        test 2 if it fails.
866    
867    9.  Added PCRE_CALL_CONVENTION just before the names of all exported functions,
868        and a #define of that name to empty if it is not externally set. This is to
869        allow users of MSVC to set it if necessary.
870    
871    10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
872        the convenience functions in the pcre_get.c source file.
873    
874    11. An option change at the start of a pattern that had top-level alternatives
875        could cause overwriting and/or a crash. This command provoked a crash in
876        some environments:
877    
878          printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
879    
880        This potential security problem was recorded as CVE-2008-2371.
881    
882    12. For a pattern where the match had to start at the beginning or immediately
883        after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
884        pcre_dfa_exec() could read past the end of the passed subject if there was
885        no match. To help with detecting such bugs (e.g. with valgrind), I modified
886        pcretest so that it places the subject at the end of its malloc-ed buffer.
887    
888    13. The change to pcretest in 12 above threw up a couple more cases when pcre_
889        exec() might read past the end of the data buffer in UTF-8 mode.
890    
891    14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
892        the data contained the byte 0x85 as part of a UTF-8 character within its
893        first line. This applied both to normal and DFA matching.
894    
895    15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
896        /^[^d]*?$/8 failed to match "abc".
897    
898    16. Added a missing copyright notice to pcrecpp_internal.h.
899    
900    17. Make it more clear in the documentation that values returned from
901        pcre_exec() in ovector are byte offsets, not character counts.
902    
903    18. Tidied a few places to stop certain compilers from issuing warnings.
904    
905    19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
906        supplied by Stefan Weber. I made a further small update for 7.8 because
907        there is a change of source arrangements: the pcre_searchfuncs.c module is
908        replaced by pcre_ucd.c.
909    
910    
911    Version 7.7 07-May-08
912  ---------------------  ---------------------
913    
914  1.  Applied Craig's patch to sort out a long long problem: "If we can't convert  1.  Applied Craig's patch to sort out a long long problem: "If we can't convert
915      a string to a long long, pretend we don't even have a long long." This is      a string to a long long, pretend we don't even have a long long." This is
916      done by checking for the strtoq, strtoll, and _strtoi64 functions.      done by checking for the strtoq, strtoll, and _strtoi64 functions.
917    
918  2.  Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with  2.  Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
919      pre-7.6 versions, which defined a global no_arg variable instead of putting      pre-7.6 versions, which defined a global no_arg variable instead of putting
920      it in the RE class. (See also #8 below.)      it in the RE class. (See also #8 below.)
921    
922  3.  Remove a line of dead code, identified by coverity and reported by Nuno  3.  Remove a line of dead code, identified by coverity and reported by Nuno
923      Lopes.      Lopes.
924    
925  4.  Fixed two related pcregrep bugs involving -r with --include or --exclude:  4.  Fixed two related pcregrep bugs involving -r with --include or --exclude:
926    
927      (1) The include/exclude patterns were being applied to the whole pathnames      (1) The include/exclude patterns were being applied to the whole pathnames
928          of files, instead of just to the final components.          of files, instead of just to the final components.
929    
930      (2) If there was more than one level of directory, the subdirectories were      (2) If there was more than one level of directory, the subdirectories were
931          skipped unless they satisfied the include/exclude conditions. This is          skipped unless they satisfied the include/exclude conditions. This is
932          inconsistent with GNU grep (and could even be seen as contrary to the          inconsistent with GNU grep (and could even be seen as contrary to the
933          pcregrep specification - which I improved to make it absolutely clear).          pcregrep specification - which I improved to make it absolutely clear).
934          The action now is always to scan all levels of directory, and just          The action now is always to scan all levels of directory, and just
935          apply the include/exclude patterns to regular files.          apply the include/exclude patterns to regular files.
936    
937  5.  Added the --include_dir and --exclude_dir patterns to pcregrep, and used  5.  Added the --include_dir and --exclude_dir patterns to pcregrep, and used
938      --exclude_dir in the tests to avoid scanning .svn directories.      --exclude_dir in the tests to avoid scanning .svn directories.
939    
940  6.  Applied Craig's patch to the QuoteMeta function so that it escapes the  6.  Applied Craig's patch to the QuoteMeta function so that it escapes the
941      NUL character as backslash + 0 rather than backslash + NUL, because PCRE      NUL character as backslash + 0 rather than backslash + NUL, because PCRE
942      doesn't support NULs in patterns.      doesn't support NULs in patterns.
943    
944  7.  Added some missing "const"s to declarations of static tables in  7.  Added some missing "const"s to declarations of static tables in
945      pcre_compile.c and pcre_dfa_exec.c.      pcre_compile.c and pcre_dfa_exec.c.
946    
947  8.  Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was  8.  Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
948      caused by fix #2  above. (Subsequently also a second patch to fix the      caused by fix #2  above. (Subsequently also a second patch to fix the
949      first patch. And a third patch - this was a messy problem.)      first patch. And a third patch - this was a messy problem.)
950    
951  9.  Applied Craig's patch to remove the use of push_back().  9.  Applied Craig's patch to remove the use of push_back().
952    
953  10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX  10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
954      matching function regexec().      matching function regexec().
955    
956  11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',  11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
957      which, however, unlike Perl's \g{...}, are subroutine calls, not back      which, however, unlike Perl's \g{...}, are subroutine calls, not back
958      references. PCRE supports relative numbers with this syntax (I don't think      references. PCRE supports relative numbers with this syntax (I don't think
959      Oniguruma does).      Oniguruma does).
960    
961  12. Previously, a group with a zero repeat such as (...){0} was completely  12. Previously, a group with a zero repeat such as (...){0} was completely
962      omitted from the compiled regex. However, this means that if the group      omitted from the compiled regex. However, this means that if the group
963      was called as a subroutine from elsewhere in the pattern, things went wrong      was called as a subroutine from elsewhere in the pattern, things went wrong
964      (an internal error was given). Such groups are now left in the compiled      (an internal error was given). Such groups are now left in the compiled
965      pattern, with a new opcode that causes them to be skipped at execution      pattern, with a new opcode that causes them to be skipped at execution
966      time.      time.
967    
968  13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes  13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
969      to the way PCRE behaves:      to the way PCRE behaves:
970    
971      (a) A lone ] character is dis-allowed (Perl treats it as data).      (a) A lone ] character is dis-allowed (Perl treats it as data).
972    
973      (b) A back reference to an unmatched subpattern matches an empty string      (b) A back reference to an unmatched subpattern matches an empty string
974          (Perl fails the current match path).          (Perl fails the current match path).
975    
976      (c) A data ] in a character class must be notated as \] because if the      (c) A data ] in a character class must be notated as \] because if the
977          first data character in a class is ], it defines an empty class. (In          first data character in a class is ], it defines an empty class. (In
978          Perl it is not possible to have an empty class.) The empty class []          Perl it is not possible to have an empty class.) The empty class []
979          never matches; it forces failure and is equivalent to (*FAIL) or (?!).          never matches; it forces failure and is equivalent to (*FAIL) or (?!).
980          The negative empty class [^] matches any one character, independently          The negative empty class [^] matches any one character, independently
981          of the DOTALL setting.          of the DOTALL setting.
982    
983  14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a  14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
984      non-existent subpattern following a character class starting with ']' and      non-existent subpattern following a character class starting with ']' and
985      containing () gave an internal compiling error instead of "reference to      containing () gave an internal compiling error instead of "reference to
986      non-existent subpattern". Fortunately, when the pattern did exist, the      non-existent subpattern". Fortunately, when the pattern did exist, the
987      compiled code was correct. (When scanning forwards to check for the      compiled code was correct. (When scanning forwards to check for the
988      existencd of the subpattern, it was treating the data ']' as terminating      existencd of the subpattern, it was treating the data ']' as terminating
989      the class, so got the count wrong. When actually compiling, the reference      the class, so got the count wrong. When actually compiling, the reference
990      was subsequently set up correctly.)      was subsequently set up correctly.)
991    
992  15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;  15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
993      it was being rejected as not supported by pcre_dfa_exec(), even though      it was being rejected as not supported by pcre_dfa_exec(), even though
994      other assertions are supported. I have made pcre_dfa_exec() support      other assertions are supported. I have made pcre_dfa_exec() support
995      (*FAIL).      (*FAIL).
996    
997  16. The implementation of 13c above involved the invention of a new opcode,  16. The implementation of 13c above involved the invention of a new opcode,
998      OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s      OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
999      cannot be changed at match time, I realized I could make a small      cannot be changed at match time, I realized I could make a small
1000      improvement to matching performance by compiling OP_ALLANY instead of      improvement to matching performance by compiling OP_ALLANY instead of
1001      OP_ANY for "." when DOTALL was set, and then removing the runtime tests      OP_ANY for "." when DOTALL was set, and then removing the runtime tests
1002      on the OP_ANY path.      on the OP_ANY path.
1003    
1004    17. Compiling pcretest on Windows with readline support failed without the
1005        following two fixes: (1) Make the unistd.h include conditional on
1006        HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
1007    
1008    18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
1009        ncurses library to be included for pcretest when ReadLine support is
1010        requested, but also to allow for it to be overridden. This patch came from
1011        Daniel Bergström.
1012    
1013    19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
1014        as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
1015        any errors with the current Unicode tables. Thanks to Peter Kankowski for
1016        spotting this.
1017    
1018    
1019  Version 7.6 28-Jan-08  Version 7.6 28-Jan-08

Legend:
Removed from v.342  
changed lines
  Added in v.608

  ViewVC Help
Powered by ViewVC 1.1.5