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

Diff of /code/trunk/ChangeLog

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

revision 390 by ph10, Tue Mar 17 10:58:16 2009 UTC revision 602 by ph10, Wed May 25 08:29:03 2011 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 7.9 xx-xxx-09  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    
57    Version 8.12 15-Jan-2011
58    ------------------------
59    
60    1.  Fixed some typos in the markup of the man pages, and wrote a script that
61        checks for such things as part of the documentation building process.
62    
63    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
64        --match-limit and --recursion-limit options (added for 8.11). In
65        particular, this made one of the standard tests fail. (The integer value
66        went into the wrong half of a long int.)
67    
68    3.  If the --colour option was given to pcregrep with -v (invert match), it
69        did strange things, either producing crazy output, or crashing. It should,
70        of course, ignore a request for colour when reporting lines that do not
71        match.
72    
73    4.  Another pcregrep bug caused similar problems if --colour was specified with
74        -M (multiline) and the pattern match finished with a line ending.
75    
76    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
77        matched in multiline mode, the following line was shown as part of the
78        match. This seems wrong, so I have changed it.
79    
80    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
81        the check for further matches in the same line (so they could be coloured)
82        to overrun the end of the current line. If another match was found, it was
83        incorrectly shown (and then shown again when found in the next line).
84    
85    7.  If pcregrep was compiled under Windows, there was a reference to the
86        function pcregrep_exit() before it was defined. I am assuming this was
87        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
88        reported by a user. I've moved the definition above the reference.
89    
90    
91    Version 8.11 10-Dec-2010
92    ------------------------
93    
94    1.  (*THEN) was not working properly if there were untried alternatives prior
95        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
96        backtracked to try for "b" instead of moving to the next alternative branch
97        at the same level (in this case, to look for "c"). The Perl documentation
98        is clear that when (*THEN) is backtracked onto, it goes to the "next
99        alternative in the innermost enclosing group".
100    
101    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
102        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
103        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
104        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
105        (*THEN).
106    
107    3.  If \s appeared in a character class, it removed the VT character from
108        the class, even if it had been included by some previous item, for example
109        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
110        of \s, but is part of the POSIX "space" class.)
111    
112    4.  A partial match never returns an empty string (because you can always
113        match an empty string at the end of the subject); however the checking for
114        an empty string was starting at the "start of match" point. This has been
115        changed to the "earliest inspected character" point, because the returned
116        data for a partial match starts at this character. This means that, for
117        example, /(?<=abc)def/ gives a partial match for the subject "abc"
118        (previously it gave "no match").
119    
120    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
121        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
122        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
123        has an implication that the given string is incomplete (because a partial
124        match is preferred over a full match). For this reason, these items now
125        give a partial match in this situation. [Aside: previously, the one case
126        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
127        match rather than a full match, which was wrong by the old rules, but is
128        now correct.]
129    
130    6.  There was a bug in the handling of #-introduced comments, recognized when
131        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
132        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
133        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
134        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
135        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
136        places in pcre_compile().
137    
138    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
139        comments when looking ahead for named forward references to subpatterns,
140        the only newline sequence it recognized was NL. It now handles newlines
141        according to the set newline convention.
142    
143    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
144        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
145        cater for a lack of strerror(). These oversights have been fixed.
146    
147    9.  Added --match-limit and --recursion-limit to pcregrep.
148    
149    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
150    
151    11. When the -o option was used, pcregrep was setting a return code of 1, even
152        when matches were found, and --line-buffered was not being honoured.
153    
154    12. Added an optional parentheses number to the -o and --only-matching options
155        of pcregrep.
156    
157    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
158        can match an empty string. The code to do it in pcretest and pcredemo
159        needed fixing:
160    
161        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
162            only one byte after an empty string match just before CRLF (this case
163            just got forgotten; "any" and "anycrlf" were OK).
164    
165        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
166            mode when an empty string match preceded an ASCII character followed by
167            a non-ASCII character. (The code for advancing by one character rather
168            than one byte was nonsense.)
169    
170        (c) The pcredemo.c sample program did not have any code at all to handle
171            the cases when CRLF is a valid newline sequence.
172    
173    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
174        as a starting offset was within the subject string. There is now a new
175        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
176        negative or greater than the length of the string. In order to test this,
177        pcretest is extended to allow the setting of negative starting offsets.
178    
179    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
180        starting offset points to the beginning of a UTF-8 character was
181        unnecessarily clumsy. I tidied it up.
182    
183    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
184        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
185    
186    17. Nobody had reported that the --include_dir option, which was added in
187        release 7.7 should have been called --include-dir (hyphen, not underscore)
188        for compatibility with GNU grep. I have changed it to --include-dir, but
189        left --include_dir as an undocumented synonym, and the same for
190        --exclude-dir, though that is not available in GNU grep, at least as of
191        release 2.5.4.
192    
193    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
194        characters from a string of bytes) have been redefined so as not to use
195        loops, in order to improve performance in some environments. At the same
196        time, I abstracted some of the common code into auxiliary macros to save
197        repetition (this should not affect the compiled code).
198    
199    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
200        compile-time error is now given if \c is not followed by an ASCII
201        character, that is, a byte less than 128. (In EBCDIC mode, the code is
202        different, and any byte value is allowed.)
203    
204    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
205        START_OPTIMIZE option, which is now allowed at compile time - but just
206        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
207        to pcregrep and other applications that have no direct access to PCRE
208        options. The new /Y option in pcretest sets this option when calling
209        pcre_compile().
210    
211    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
212        back references. Groups containing recursive back references were forced to
213        be atomic by that change, but in the case of named groups, the amount of
214        memory required was incorrectly computed, leading to "Failed: internal
215        error: code overflow". This has been fixed.
216    
217    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
218        pcretest.c, to avoid build problems in some Borland environments.
219    
220    
221    Version 8.10 25-Jun-2010
222    ------------------------
223    
224    1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
225        THEN.
226    
227    2.  (*ACCEPT) was not working when inside an atomic group.
228    
229    3.  Inside a character class, \B is treated as a literal by default, but
230        faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
231        causes the error). The code is unchanged, but I tidied the documentation.
232    
233    4.  Inside a character class, PCRE always treated \R and \X as literals,
234        whereas Perl faults them if its -w option is set. I have changed PCRE so
235        that it faults them when PCRE_EXTRA is set.
236    
237    5.  Added support for \N, which always matches any character other than
238        newline. (It is the same as "." when PCRE_DOTALL is not set.)
239    
240    6.  When compiling pcregrep with newer versions of gcc which may have
241        FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
242        declared with attribute warn_unused_result" were given. Just casting the
243        result to (void) does not stop the warnings; a more elaborate fudge is
244        needed. I've used a macro to implement this.
245    
246    7.  Minor change to pcretest.c to avoid a compiler warning.
247    
248    8.  Added four artifical Unicode properties to help with an option to make
249        \s etc use properties (see next item). The new properties are: Xan
250        (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
251    
252    9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
253        use Unicode properties. (*UCP) at the start of a pattern can be used to set
254        this option. Modified pcretest to add /W to test this facility. Added
255        REG_UCP to make it available via the POSIX interface.
256    
257    10. Added --line-buffered to pcregrep.
258    
259    11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
260        studied, and the match started with a letter with a code point greater than
261        127 whose first byte was different to the first byte of the other case of
262        the letter, the other case of this starting letter was not recognized
263        (#976).
264    
265    12. If a pattern that was studied started with a repeated Unicode property
266        test, for example, \p{Nd}+, there was the theoretical possibility of
267        setting up an incorrect bitmap of starting bytes, but fortunately it could
268        not have actually happened in practice until change 8 above was made (it
269        added property types that matched character-matching opcodes).
270    
271    13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
272        possible starting bytes for non-anchored patterns.
273    
274    14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
275        \R, and also a number of cases that involve Unicode properties, both
276        explicit and implicit when PCRE_UCP is set.
277    
278    15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
279        input, it could crash or give wrong results if characters with values
280        greater than 0xc0 were present in the subject string. (Detail: it assumed
281        UTF-8 input when processing these items.)
282    
283    16. Added a lot of (int) casts to avoid compiler warnings in systems where
284        size_t is 64-bit (#991).
285    
286    17. Added a check for running out of memory when PCRE is compiled with
287        --disable-stack-for-recursion (#990).
288    
289    18. If the last data line in a file for pcretest does not have a newline on
290        the end, a newline was missing in the output.
291    
292    19. The default pcre_chartables.c file recognizes only ASCII characters (values
293        less than 128) in its various bitmaps. However, there is a facility for
294        generating tables according to the current locale when PCRE is compiled. It
295        turns out that in some environments, 0x85 and 0xa0, which are Unicode space
296        characters, are recognized by isspace() and therefore were getting set in
297        these tables, and indeed these tables seem to approximate to ISO 8859. This
298        caused a problem in UTF-8 mode when pcre_study() was used to create a list
299        of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
300        which of course cannot start UTF-8 characters. I have changed the code so
301        that only real ASCII characters (less than 128) and the correct starting
302        bytes for UTF-8 encodings are set for characters greater than 127 when in
303        UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
304        altogether.)
305    
306    20. Added the /T option to pcretest so as to be able to run tests with non-
307        standard character tables, thus making it possible to include the tests
308        used for 19 above in the standard set of tests.
309    
310    21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
311        reference to a subpattern the other side of a comment that contains an
312        opening parenthesis caused either an internal compiling error, or a
313        reference to the wrong subpattern.
314    
315    
316    Version 8.02 19-Mar-2010
317    ------------------------
318    
319    1.  The Unicode data tables have been updated to Unicode 5.2.0.
320    
321    2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
322        configured.
323    
324    3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
325        original author of that file, following a query about its status.
326    
327    4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
328        inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
329    
330    5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
331        quantifier applied to a forward-referencing subroutine call, could compile
332        incorrect code or give the error "internal error: previously-checked
333        referenced subpattern not found".
334    
335    6.  Both MS Visual Studio and Symbian OS have problems with initializing
336        variables to point to external functions. For these systems, therefore,
337        pcre_malloc etc. are now initialized to local functions that call the
338        relevant global functions.
339    
340    7.  There were two entries missing in the vectors called coptable and poptable
341        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
342        I've fixed the data, and added a kludgy way of testing at compile time that
343        the lengths are correct (equal to the number of opcodes).
344    
345    8.  Following on from 7, I added a similar kludge to check the length of the
346        eint vector in pcreposix.c.
347    
348    9.  Error texts for pcre_compile() are held as one long string to avoid too
349        much relocation at load time. To find a text, the string is searched,
350        counting zeros. There was no check for running off the end of the string,
351        which could happen if a new error number was added without updating the
352        string.
353    
354    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
355    
356    11. \K was not working if it appeared in an atomic group or in a group that
357        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
358        \K is "not well defined" if used in an assertion. PCRE now accepts it if
359        the assertion is positive, but not if it is negative.
360    
361    12. Change 11 fortuitously reduced the size of the stack frame used in the
362        "match()" function of pcre_exec.c by one pointer. Forthcoming
363        implementation of support for (*MARK) will need an extra pointer on the
364        stack; I have reserved it now, so that the stack frame size does not
365        decrease.
366    
367    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
368        item in branch that calls a recursion is a subroutine call - as in the
369        second branch in the above example - was incorrectly given the compile-
370        time error "recursive call could loop indefinitely" because pcre_compile()
371        was not correctly checking the subroutine for matching a non-empty string.
372    
373    14. The checks for overrunning compiling workspace could trigger after an
374        overrun had occurred. This is a "should never occur" error, but it can be
375        triggered by pathological patterns such as hundreds of nested parentheses.
376        The checks now trigger 100 bytes before the end of the workspace.
377    
378    15. Fix typo in configure.ac: "srtoq" should be "strtoq".
379    
380    
381    Version 8.01 19-Jan-2010
382    ------------------------
383    
384    1.  If a pattern contained a conditional subpattern with only one branch (in
385        particular, this includes all (*DEFINE) patterns), a call to pcre_study()
386        computed the wrong minimum data length (which is of course zero for such
387        subpatterns). This could cause incorrect "no match" results.
388    
389    2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
390        the pattern is reset in the first branch, pcre_compile() failed with
391        "internal error: code overflow at offset...". This happened only when
392        the reset was to the original external option setting. (An optimization
393        abstracts leading options settings into an external setting, which was the
394        cause of this.)
395    
396    3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
397        of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
398        assertion pattern did not match (meaning that the assertion was true), it
399        was incorrectly treated as false if the SKIP had been reached during the
400        matching. This also applied to assertions used as conditions.
401    
402    4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
403        assertion subpattern, including such a pattern used as a condition,
404        unpredictable results occurred, instead of the error return
405        PCRE_ERROR_DFA_UITEM.
406    
407    5.  The C++ GlobalReplace function was not working like Perl for the special
408        situation when an empty string is matched. It now does the fancy magic
409        stuff that is necessary.
410    
411    6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
412        removed. (These were left over from very, very early versions of PCRE.)
413    
414    7.  Some cosmetic changes to the code to make life easier when compiling it
415        as part of something else:
416    
417        (a) Change DEBUG to PCRE_DEBUG.
418    
419        (b) In pcre_compile(), rename the member of the "branch_chain" structure
420            called "current" as "current_branch", to prevent a collision with the
421            Linux macro when compiled as a kernel module.
422    
423        (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
424            prevent a collision with the Linux macro when compiled as a kernel
425            module.
426    
427    8.  In pcre_compile() there are some checks for integer overflows that used to
428        cast potentially large values to (double). This has been changed to that
429        when building, a check for int64_t is made, and if it is found, it is used
430        instead, thus avoiding the use of floating point arithmetic. (There is no
431        other use of FP in PCRE.) If int64_t is not found, the fallback is to
432        double.
433    
434    9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
435        2005 (difference between two addresses compared to an unsigned value).
436    
437    10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
438        custom one, because of the following reported problem in Windows:
439    
440          - libbz2 uses the Pascal calling convention (WINAPI) for the functions
441              under Win32.
442          - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
443              therefore missing the function definition.
444          - The compiler thus generates a "C" signature for the test function.
445          - The linker fails to find the "C" function.
446          - PCRE fails to configure if asked to do so against libbz2.
447    
448    11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
449        messages were output:
450    
451          Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
452          rerunning libtoolize, to keep the correct libtool macros in-tree.
453          Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
454    
455        I have done both of these things.
456    
457    12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
458        most of the time, it *can* run out if it is given a pattern that contains a
459        runaway infinite recursion. I updated the discussion in the pcrestack man
460        page.
461    
462    13. Now that we have gone to the x.xx style of version numbers, the minor
463        version may start with zero. Using 08 or 09 is a bad idea because users
464        might check the value of PCRE_MINOR in their code, and 08 or 09 may be
465        interpreted as invalid octal numbers. I've updated the previous comment in
466        configure.ac, and also added a check that gives an error if 08 or 09 are
467        used.
468    
469    14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
470        causing partial matching to fail when the end of the subject matched \W
471        in a UTF-8 pattern where \W was quantified with a minimum of 3.
472    
473    15. There were some discrepancies between the declarations in pcre_internal.h
474        of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
475        their definitions. The declarations used "const uschar *" and the
476        definitions used USPTR. Even though USPTR is normally defined as "const
477        unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
478        reported that: "This difference in casting confuses some C++ compilers, for
479        example, SunCC recognizes above declarations as different functions and
480        generates broken code for hbpcre." I have changed the declarations to use
481        USPTR.
482    
483    16. GNU libtool is named differently on some systems. The autogen.sh script now
484        tries several variants such as glibtoolize (MacOSX) and libtoolize1x
485        (FreeBSD).
486    
487    17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
488        (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
489        comment: "Figure out how to create a longlong from a string: strtoll and
490        equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
491        instance, but it only takes 2 args instead of 3!"
492    
493    18. A subtle bug concerned with back references has been fixed by a change of
494        specification, with a corresponding code fix. A pattern such as
495        ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
496        refers, was giving matches when it shouldn't. For example, xa=xaaa would
497        match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
498        same bug. Such groups have to be quantified to be useful, or contained
499        inside another quantified group. (If there's no repetition, the reference
500        can never match.) The problem arises because, having left the group and
501        moved on to the rest of the pattern, a later failure that backtracks into
502        the group uses the captured value from the final iteration of the group
503        rather than the correct earlier one. I have fixed this in PCRE by forcing
504        any group that contains a reference to itself to be an atomic group; that
505        is, there cannot be any backtracking into it once it has completed. This is
506        similar to recursive and subroutine calls.
507    
508    
509    Version 8.00 19-Oct-09
510    ----------------------
511    
512    1.  The table for translating pcre_compile() error codes into POSIX error codes
513        was out-of-date, and there was no check on the pcre_compile() error code
514        being within the table. This could lead to an OK return being given in
515        error.
516    
517    2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
518        "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
519        in a Windows environment.
520    
521    3.  The pcregrep --count option prints the count for each file even when it is
522        zero, as does GNU grep. However, pcregrep was also printing all files when
523        --files-with-matches was added. Now, when both options are given, it prints
524        counts only for those files that have at least one match. (GNU grep just
525        prints the file name in this circumstance, but including the count seems
526        more useful - otherwise, why use --count?) Also ensured that the
527        combination -clh just lists non-zero counts, with no names.
528    
529    4.  The long form of the pcregrep -F option was incorrectly implemented as
530        --fixed_strings instead of --fixed-strings. This is an incompatible change,
531        but it seems right to fix it, and I didn't think it was worth preserving
532        the old behaviour.
533    
534    5.  The command line items --regex=pattern and --regexp=pattern were not
535        recognized by pcregrep, which required --regex pattern or --regexp pattern
536        (with a space rather than an '='). The man page documented the '=' forms,
537        which are compatible with GNU grep; these now work.
538    
539    6.  No libpcreposix.pc file was created for pkg-config; there was just
540        libpcre.pc and libpcrecpp.pc. The omission has been rectified.
541    
542    7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
543        when UCP support is not needed, by modifying the Python script that
544        generates it from Unicode data files. This should not matter if the module
545        is correctly used as a library, but I received one complaint about 50K of
546        unwanted data. My guess is that the person linked everything into his
547        program rather than using a library. Anyway, it does no harm.
548    
549    8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
550        was a minimum greater than 1 for a wide character in a possessive
551        repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
552        which had an unlimited repeat of a nested, fixed maximum repeat of a wide
553        character. Chaos in the form of incorrect output or a compiling loop could
554        result.
555    
556    9.  The restrictions on what a pattern can contain when partial matching is
557        requested for pcre_exec() have been removed. All patterns can now be
558        partially matched by this function. In addition, if there are at least two
559        slots in the offset vector, the offset of the earliest inspected character
560        for the match and the offset of the end of the subject are set in them when
561        PCRE_ERROR_PARTIAL is returned.
562    
563    10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
564        synonymous with PCRE_PARTIAL, for backwards compatibility, and
565        PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
566        and may be more useful for multi-segment matching.
567    
568    11. Partial matching with pcre_exec() is now more intuitive. A partial match
569        used to be given if ever the end of the subject was reached; now it is
570        given only if matching could not proceed because another character was
571        needed. This makes a difference in some odd cases such as Z(*FAIL) with the
572        string "Z", which now yields "no match" instead of "partial match". In the
573        case of pcre_dfa_exec(), "no match" is given if every matching path for the
574        final character ended with (*FAIL).
575    
576    12. Restarting a match using pcre_dfa_exec() after a partial match did not work
577        if the pattern had a "must contain" character that was already found in the
578        earlier partial match, unless partial matching was again requested. For
579        example, with the pattern /dog.(body)?/, the "must contain" character is
580        "g". If the first part-match was for the string "dog", restarting with
581        "sbody" failed. This bug has been fixed.
582    
583    13. The string returned by pcre_dfa_exec() after a partial match has been
584        changed so that it starts at the first inspected character rather than the
585        first character of the match. This makes a difference only if the pattern
586        starts with a lookbehind assertion or \b or \B (\K is not supported by
587        pcre_dfa_exec()). It's an incompatible change, but it makes the two
588        matching functions compatible, and I think it's the right thing to do.
589    
590    14. Added a pcredemo man page, created automatically from the pcredemo.c file,
591        so that the demonstration program is easily available in environments where
592        PCRE has not been installed from source.
593    
594    15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
595        libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
596        library.
597    
598    16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
599        It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
600        is not the first non-POSIX option to be added. Clearly some people find
601        these options useful.
602    
603    17. If a caller to the POSIX matching function regexec() passes a non-zero
604        value for nmatch with a NULL value for pmatch, the value of
605        nmatch is forced to zero.
606    
607    18. RunGrepTest did not have a test for the availability of the -u option of
608        the diff command, as RunTest does. It now checks in the same way as
609        RunTest, and also checks for the -b option.
610    
611    19. If an odd number of negated classes containing just a single character
612        interposed, within parentheses, between a forward reference to a named
613        subpattern and the definition of the subpattern, compilation crashed with
614        an internal error, complaining that it could not find the referenced
615        subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
616        [The bug was that it was starting one character too far in when skipping
617        over the character class, thus treating the ] as data rather than
618        terminating the class. This meant it could skip too much.]
619    
620    20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
621        /g option in pcretest when the pattern contains \K, which makes it possible
622        to have an empty string match not at the start, even when the pattern is
623        anchored. Updated pcretest and pcredemo to use this option.
624    
625    21. If the maximum number of capturing subpatterns in a recursion was greater
626        than the maximum at the outer level, the higher number was returned, but
627        with unset values at the outer level. The correct (outer level) value is
628        now given.
629    
630    22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
631        PCRE did not set those parentheses (unlike Perl). I have now found a way to
632        make it do so. The string so far is captured, making this feature
633        compatible with Perl.
634    
635    23. The tests have been re-organized, adding tests 11 and 12, to make it
636        possible to check the Perl 5.10 features against Perl 5.10.
637    
638    24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
639        pattern matches a fixed length string. PCRE did not allow this; now it
640        does. Neither allows recursion.
641    
642    25. I finally figured out how to implement a request to provide the minimum
643        length of subject string that was needed in order to match a given pattern.
644        (It was back references and recursion that I had previously got hung up
645        on.) This code has now been added to pcre_study(); it finds a lower bound
646        to the length of subject needed. It is not necessarily the greatest lower
647        bound, but using it to avoid searching strings that are too short does give
648        some useful speed-ups. The value is available to calling programs via
649        pcre_fullinfo().
650    
651    26. While implementing 25, I discovered to my embarrassment that pcretest had
652        not been passing the result of pcre_study() to pcre_dfa_exec(), so the
653        study optimizations had never been tested with that matching function.
654        Oops. What is worse, even when it was passed study data, there was a bug in
655        pcre_dfa_exec() that meant it never actually used it. Double oops. There
656        were also very few tests of studied patterns with pcre_dfa_exec().
657    
658    27. If (?| is used to create subpatterns with duplicate numbers, they are now
659        allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
660        on the other side of the coin, they are no longer allowed to have different
661        names, because these cannot be distinguished in PCRE, and this has caused
662        confusion. (This is a difference from Perl.)
663    
664    28. When duplicate subpattern names are present (necessarily with different
665        numbers, as required by 27 above), and a test is made by name in a
666        conditional pattern, either for a subpattern having been matched, or for
667        recursion in such a pattern, all the associated numbered subpatterns are
668        tested, and the overall condition is true if the condition is true for any
669        one of them. This is the way Perl works, and is also more like the way
670        testing by number works.
671    
672    
673    Version 7.9 11-Apr-09
674  ---------------------  ---------------------
675    
676  1.  When building with support for bzlib/zlib (pcregrep) and/or readline  1.  When building with support for bzlib/zlib (pcregrep) and/or readline
677      (pcretest), all targets were linked against these libraries. This included      (pcretest), all targets were linked against these libraries. This included
678      libpcre, libpcreposix, and libpcrecpp, even though they do not use these      libpcre, libpcreposix, and libpcrecpp, even though they do not use these
679      libraries. This caused unwanted dependencies to be created. This problem      libraries. This caused unwanted dependencies to be created. This problem
680      has been fixed, and now only pcregrep is linked with bzlib/zlib and only      has been fixed, and now only pcregrep is linked with bzlib/zlib and only
681      pcretest is linked with readline.      pcretest is linked with readline.
682    
683  2.  The "typedef int BOOL" in pcre_internal.h that was included inside the  2.  The "typedef int BOOL" in pcre_internal.h that was included inside the
684      "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been      "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
685      moved outside it again, because FALSE and TRUE are already defined in AIX,      moved outside it again, because FALSE and TRUE are already defined in AIX,
686      but BOOL is not.      but BOOL is not.
687    
688  3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and  3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
689      PCRE_MATCH_LIMIT_RETURSION values as ints, when they should be long ints.      PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
690    
691  4.  The pcregrep documentation said spaces were inserted as well as colons (or  4.  The pcregrep documentation said spaces were inserted as well as colons (or
692      hyphens) following file names and line numbers when outputting matching      hyphens) following file names and line numbers when outputting matching
693      lines. This is not true; no spaces are inserted. I have also clarified the      lines. This is not true; no spaces are inserted. I have also clarified the
694      wording for the --colour (or --color) option.      wording for the --colour (or --color) option.
695    
696  5.  In pcregrep, when --colour was used with -o, the list of matching strings  5.  In pcregrep, when --colour was used with -o, the list of matching strings
697      was not coloured; this is different to GNU grep, so I have changed it to be      was not coloured; this is different to GNU grep, so I have changed it to be
698      the same.      the same.
699    
700  6.  When --colo(u)r was used in pcregrep, only the first matching substring in  6.  When --colo(u)r was used in pcregrep, only the first matching substring in
701      each matching line was coloured. Now it goes on to look for further matches      each matching line was coloured. Now it goes on to look for further matches
702      of any of the test patterns, which is the same behaviour as GNU grep.      of any of the test patterns, which is the same behaviour as GNU grep.
703    
704  7.  A pattern that could match an empty string could cause pcregrep to loop; it  7.  A pattern that could match an empty string could cause pcregrep to loop; it
705      doesn't make sense to accept an empty string match in pcregrep, so I have      doesn't make sense to accept an empty string match in pcregrep, so I have
706      locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this      locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
707      seems to be how GNU grep behaves.      seems to be how GNU grep behaves.
708    
709  8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at  8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
710      start or after a newline", because the conditional assertion was not being      start or after a newline", because the conditional assertion was not being
711      correctly handled. The rule now is that both the assertion and what follows      correctly handled. The rule now is that both the assertion and what follows
712      in the first alternative must satisfy the test.      in the first alternative must satisfy the test.
713    
714  9.  If auto-callout was enabled in a pattern with a conditional group, PCRE  9.  If auto-callout was enabled in a pattern with a conditional group whose
715      could crash during matching.      condition was an assertion, PCRE could crash during matching, both with
716        pcre_exec() and pcre_dfa_exec().
717  10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was  
718      used for matching.  10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
719        used for matching.
720  11. Unicode property support in character classes was not working for  
721    11. Unicode property support in character classes was not working for
722      characters (bytes) greater than 127 when not in UTF-8 mode.      characters (bytes) greater than 127 when not in UTF-8 mode.
723    
724  12. Added the -M command line option to pcretest.  12. Added the -M command line option to pcretest.
725    
726  14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.  14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
727    
728  15. Added the PCRE_NO_START_OPTIMIZE match-time option.  15. Added the PCRE_NO_START_OPTIMIZE match-time option.
729    
730  16. Added comments and documentation about mis-use of no_arg in the C++  16. Added comments and documentation about mis-use of no_arg in the C++
731      wrapper.      wrapper.
732    
733    17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
734        from Martin Jerabek that uses macro names for all relevant character and
735        string constants.
736    
737    18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
738        SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
739        SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
740        these, but not everybody uses configure.
741    
742    19. A conditional group that had only one branch was not being correctly
743        recognized as an item that could match an empty string. This meant that an
744        enclosing group might also not be so recognized, causing infinite looping
745        (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
746        with the subject "ab", where knowledge that the repeated group can match
747        nothing is needed in order to break the loop.
748    
749    20. If a pattern that was compiled with callouts was matched using pcre_dfa_
750        exec(), but without supplying a callout function, matching went wrong.
751    
752    21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
753        leak if the size of the offset vector was greater than 30. When the vector
754        is smaller, the saved offsets during recursion go onto a local stack
755        vector, but for larger vectors malloc() is used. It was failing to free
756        when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
757        error, in fact).
758    
759    22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
760        heapframe that is used only when UTF-8 support is enabled. This caused no
761        problem, but was untidy.
762    
763    23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
764        CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
765        included within another project.
766    
767    24. Steven Van Ingelgem's patches to add more options to the CMake support,
768        slightly modified by me:
769    
770          (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
771              not building pcregrep.
772    
773          (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
774              if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
775    
776    25. Forward references, both numeric and by name, in patterns that made use of
777        duplicate group numbers, could behave incorrectly or give incorrect errors,
778        because when scanning forward to find the reference group, PCRE was not
779        taking into account the duplicate group numbers. A pattern such as
780        ^X(?3)(a)(?|(b)|(q))(Y) is an example.
781    
782    26. Changed a few more instances of "const unsigned char *" to USPTR, making
783        the feature of a custom pointer more persuasive (as requested by a user).
784    
785    27. Wrapped the definitions of fileno and isatty for Windows, which appear in
786        pcretest.c, inside #ifndefs, because it seems they are sometimes already
787        pre-defined.
788    
789    28. Added support for (*UTF8) at the start of a pattern.
790    
791    29. Arrange for flags added by the "release type" setting in CMake to be shown
792        in the configuration summary.
793    
794    
795  Version 7.8 05-Sep-08  Version 7.8 05-Sep-08
796  ---------------------  ---------------------

Legend:
Removed from v.390  
changed lines
  Added in v.602

webmaster@exim.org
ViewVC Help
Powered by ViewVC 1.1.12