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

Diff of /code/trunk/ChangeLog

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

revision 496 by ph10, Tue Mar 2 19:11:17 2010 UTC revision 604 by ph10, Thu Jun 2 19:04:54 2011 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 8.02 01-Mar-2010  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    
74    Version 8.12 15-Jan-2011
75    ------------------------
76    
77    1.  Fixed some typos in the markup of the man pages, and wrote a script that
78        checks for such things as part of the documentation building process.
79    
80    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
81        --match-limit and --recursion-limit options (added for 8.11). In
82        particular, this made one of the standard tests fail. (The integer value
83        went into the wrong half of a long int.)
84    
85    3.  If the --colour option was given to pcregrep with -v (invert match), it
86        did strange things, either producing crazy output, or crashing. It should,
87        of course, ignore a request for colour when reporting lines that do not
88        match.
89    
90    4.  Another pcregrep bug caused similar problems if --colour was specified with
91        -M (multiline) and the pattern match finished with a line ending.
92    
93    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
94        matched in multiline mode, the following line was shown as part of the
95        match. This seems wrong, so I have changed it.
96    
97    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
98        the check for further matches in the same line (so they could be coloured)
99        to overrun the end of the current line. If another match was found, it was
100        incorrectly shown (and then shown again when found in the next line).
101    
102    7.  If pcregrep was compiled under Windows, there was a reference to the
103        function pcregrep_exit() before it was defined. I am assuming this was
104        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
105        reported by a user. I've moved the definition above the reference.
106    
107    
108    Version 8.11 10-Dec-2010
109    ------------------------
110    
111    1.  (*THEN) was not working properly if there were untried alternatives prior
112        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
113        backtracked to try for "b" instead of moving to the next alternative branch
114        at the same level (in this case, to look for "c"). The Perl documentation
115        is clear that when (*THEN) is backtracked onto, it goes to the "next
116        alternative in the innermost enclosing group".
117    
118    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
119        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
120        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
121        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
122        (*THEN).
123    
124    3.  If \s appeared in a character class, it removed the VT character from
125        the class, even if it had been included by some previous item, for example
126        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
127        of \s, but is part of the POSIX "space" class.)
128    
129    4.  A partial match never returns an empty string (because you can always
130        match an empty string at the end of the subject); however the checking for
131        an empty string was starting at the "start of match" point. This has been
132        changed to the "earliest inspected character" point, because the returned
133        data for a partial match starts at this character. This means that, for
134        example, /(?<=abc)def/ gives a partial match for the subject "abc"
135        (previously it gave "no match").
136    
137    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
138        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
139        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
140        has an implication that the given string is incomplete (because a partial
141        match is preferred over a full match). For this reason, these items now
142        give a partial match in this situation. [Aside: previously, the one case
143        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
144        match rather than a full match, which was wrong by the old rules, but is
145        now correct.]
146    
147    6.  There was a bug in the handling of #-introduced comments, recognized when
148        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
149        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
150        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
151        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
152        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
153        places in pcre_compile().
154    
155    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
156        comments when looking ahead for named forward references to subpatterns,
157        the only newline sequence it recognized was NL. It now handles newlines
158        according to the set newline convention.
159    
160    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
161        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
162        cater for a lack of strerror(). These oversights have been fixed.
163    
164    9.  Added --match-limit and --recursion-limit to pcregrep.
165    
166    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
167    
168    11. When the -o option was used, pcregrep was setting a return code of 1, even
169        when matches were found, and --line-buffered was not being honoured.
170    
171    12. Added an optional parentheses number to the -o and --only-matching options
172        of pcregrep.
173    
174    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
175        can match an empty string. The code to do it in pcretest and pcredemo
176        needed fixing:
177    
178        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
179            only one byte after an empty string match just before CRLF (this case
180            just got forgotten; "any" and "anycrlf" were OK).
181    
182        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
183            mode when an empty string match preceded an ASCII character followed by
184            a non-ASCII character. (The code for advancing by one character rather
185            than one byte was nonsense.)
186    
187        (c) The pcredemo.c sample program did not have any code at all to handle
188            the cases when CRLF is a valid newline sequence.
189    
190    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
191        as a starting offset was within the subject string. There is now a new
192        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
193        negative or greater than the length of the string. In order to test this,
194        pcretest is extended to allow the setting of negative starting offsets.
195    
196    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
197        starting offset points to the beginning of a UTF-8 character was
198        unnecessarily clumsy. I tidied it up.
199    
200    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
201        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
202    
203    17. Nobody had reported that the --include_dir option, which was added in
204        release 7.7 should have been called --include-dir (hyphen, not underscore)
205        for compatibility with GNU grep. I have changed it to --include-dir, but
206        left --include_dir as an undocumented synonym, and the same for
207        --exclude-dir, though that is not available in GNU grep, at least as of
208        release 2.5.4.
209    
210    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
211        characters from a string of bytes) have been redefined so as not to use
212        loops, in order to improve performance in some environments. At the same
213        time, I abstracted some of the common code into auxiliary macros to save
214        repetition (this should not affect the compiled code).
215    
216    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
217        compile-time error is now given if \c is not followed by an ASCII
218        character, that is, a byte less than 128. (In EBCDIC mode, the code is
219        different, and any byte value is allowed.)
220    
221    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
222        START_OPTIMIZE option, which is now allowed at compile time - but just
223        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
224        to pcregrep and other applications that have no direct access to PCRE
225        options. The new /Y option in pcretest sets this option when calling
226        pcre_compile().
227    
228    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
229        back references. Groups containing recursive back references were forced to
230        be atomic by that change, but in the case of named groups, the amount of
231        memory required was incorrectly computed, leading to "Failed: internal
232        error: code overflow". This has been fixed.
233    
234    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
235        pcretest.c, to avoid build problems in some Borland environments.
236    
237    
238    Version 8.10 25-Jun-2010
239    ------------------------
240    
241    1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
242        THEN.
243    
244    2.  (*ACCEPT) was not working when inside an atomic group.
245    
246    3.  Inside a character class, \B is treated as a literal by default, but
247        faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
248        causes the error). The code is unchanged, but I tidied the documentation.
249    
250    4.  Inside a character class, PCRE always treated \R and \X as literals,
251        whereas Perl faults them if its -w option is set. I have changed PCRE so
252        that it faults them when PCRE_EXTRA is set.
253    
254    5.  Added support for \N, which always matches any character other than
255        newline. (It is the same as "." when PCRE_DOTALL is not set.)
256    
257    6.  When compiling pcregrep with newer versions of gcc which may have
258        FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
259        declared with attribute warn_unused_result" were given. Just casting the
260        result to (void) does not stop the warnings; a more elaborate fudge is
261        needed. I've used a macro to implement this.
262    
263    7.  Minor change to pcretest.c to avoid a compiler warning.
264    
265    8.  Added four artifical Unicode properties to help with an option to make
266        \s etc use properties (see next item). The new properties are: Xan
267        (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
268    
269    9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
270        use Unicode properties. (*UCP) at the start of a pattern can be used to set
271        this option. Modified pcretest to add /W to test this facility. Added
272        REG_UCP to make it available via the POSIX interface.
273    
274    10. Added --line-buffered to pcregrep.
275    
276    11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
277        studied, and the match started with a letter with a code point greater than
278        127 whose first byte was different to the first byte of the other case of
279        the letter, the other case of this starting letter was not recognized
280        (#976).
281    
282    12. If a pattern that was studied started with a repeated Unicode property
283        test, for example, \p{Nd}+, there was the theoretical possibility of
284        setting up an incorrect bitmap of starting bytes, but fortunately it could
285        not have actually happened in practice until change 8 above was made (it
286        added property types that matched character-matching opcodes).
287    
288    13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
289        possible starting bytes for non-anchored patterns.
290    
291    14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
292        \R, and also a number of cases that involve Unicode properties, both
293        explicit and implicit when PCRE_UCP is set.
294    
295    15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
296        input, it could crash or give wrong results if characters with values
297        greater than 0xc0 were present in the subject string. (Detail: it assumed
298        UTF-8 input when processing these items.)
299    
300    16. Added a lot of (int) casts to avoid compiler warnings in systems where
301        size_t is 64-bit (#991).
302    
303    17. Added a check for running out of memory when PCRE is compiled with
304        --disable-stack-for-recursion (#990).
305    
306    18. If the last data line in a file for pcretest does not have a newline on
307        the end, a newline was missing in the output.
308    
309    19. The default pcre_chartables.c file recognizes only ASCII characters (values
310        less than 128) in its various bitmaps. However, there is a facility for
311        generating tables according to the current locale when PCRE is compiled. It
312        turns out that in some environments, 0x85 and 0xa0, which are Unicode space
313        characters, are recognized by isspace() and therefore were getting set in
314        these tables, and indeed these tables seem to approximate to ISO 8859. This
315        caused a problem in UTF-8 mode when pcre_study() was used to create a list
316        of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
317        which of course cannot start UTF-8 characters. I have changed the code so
318        that only real ASCII characters (less than 128) and the correct starting
319        bytes for UTF-8 encodings are set for characters greater than 127 when in
320        UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
321        altogether.)
322    
323    20. Added the /T option to pcretest so as to be able to run tests with non-
324        standard character tables, thus making it possible to include the tests
325        used for 19 above in the standard set of tests.
326    
327    21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
328        reference to a subpattern the other side of a comment that contains an
329        opening parenthesis caused either an internal compiling error, or a
330        reference to the wrong subpattern.
331    
332    
333    Version 8.02 19-Mar-2010
334  ------------------------  ------------------------
335    
336  1.  The Unicode data tables have been updated to Unicode 5.2.0.  1.  The Unicode data tables have been updated to Unicode 5.2.0.
337    
338  2.  Added the option --libs-cpp to pcre-config, but only when C++ support is  2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
339      configured.      configured.
340    
341  3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the  3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
342      original author of that file, following a query about its status.      original author of that file, following a query about its status.
343    
344  4.  On systems that do not have stdint.h (e.g. Solaris), check for and include  4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
345      inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.      inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
346    
347  5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive  5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
348      quantifier applied to a forward-referencing subroutine call, could compile      quantifier applied to a forward-referencing subroutine call, could compile
349      incorrect code or give the error "internal error: previously-checked      incorrect code or give the error "internal error: previously-checked
350      referenced subpattern not found".      referenced subpattern not found".
351    
352    6.  Both MS Visual Studio and Symbian OS have problems with initializing
353        variables to point to external functions. For these systems, therefore,
354        pcre_malloc etc. are now initialized to local functions that call the
355        relevant global functions.
356    
357    7.  There were two entries missing in the vectors called coptable and poptable
358        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
359        I've fixed the data, and added a kludgy way of testing at compile time that
360        the lengths are correct (equal to the number of opcodes).
361    
362    8.  Following on from 7, I added a similar kludge to check the length of the
363        eint vector in pcreposix.c.
364    
365    9.  Error texts for pcre_compile() are held as one long string to avoid too
366        much relocation at load time. To find a text, the string is searched,
367        counting zeros. There was no check for running off the end of the string,
368        which could happen if a new error number was added without updating the
369        string.
370    
371    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
372    
373    11. \K was not working if it appeared in an atomic group or in a group that
374        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
375        \K is "not well defined" if used in an assertion. PCRE now accepts it if
376        the assertion is positive, but not if it is negative.
377    
378    12. Change 11 fortuitously reduced the size of the stack frame used in the
379        "match()" function of pcre_exec.c by one pointer. Forthcoming
380        implementation of support for (*MARK) will need an extra pointer on the
381        stack; I have reserved it now, so that the stack frame size does not
382        decrease.
383    
384    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
385        item in branch that calls a recursion is a subroutine call - as in the
386        second branch in the above example - was incorrectly given the compile-
387        time error "recursive call could loop indefinitely" because pcre_compile()
388        was not correctly checking the subroutine for matching a non-empty string.
389    
390    14. The checks for overrunning compiling workspace could trigger after an
391        overrun had occurred. This is a "should never occur" error, but it can be
392        triggered by pathological patterns such as hundreds of nested parentheses.
393        The checks now trigger 100 bytes before the end of the workspace.
394    
395    15. Fix typo in configure.ac: "srtoq" should be "strtoq".
396    
397    
398  Version 8.01 19-Jan-2010  Version 8.01 19-Jan-2010
399  ------------------------  ------------------------

Legend:
Removed from v.496  
changed lines
  Added in v.604

  ViewVC Help
Powered by ViewVC 1.1.5