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

Diff of /code/trunk/ChangeLog

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

revision 373 by ph10, Fri Sep 5 10:25:46 2008 UTC revision 573 by ph10, Fri Nov 19 19:29:44 2010 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 7.8 25-Aug-08  Version 8.11 10-Oct-2010
5    ------------------------
6    
7    1.  (*THEN) was not working properly if there were untried alternatives prior
8        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
9        backtracked to try for "b" instead of moving to the next alternative branch
10        at the same level (in this case, to look for "c"). The Perl documentation
11        is clear that when (*THEN) is backtracked onto, it goes to the "next
12        alternative in the innermost enclosing group".
13    
14    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
15        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
16        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
17        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
18        (*THEN).
19    
20    3.  If \s appeared in a character class, it removed the VT character from
21        the class, even if it had been included by some previous item, for example
22        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
23        of \s, but is part of the POSIX "space" class.)
24    
25    4.  A partial match never returns an empty string (because you can always
26        match an empty string at the end of the subject); however the checking for
27        an empty string was starting at the "start of match" point. This has been
28        changed to the "earliest inspected character" point, because the returned
29        data for a partial match starts at this character. This means that, for
30        example, /(?<=abc)def/ gives a partial match for the subject "abc"
31        (previously it gave "no match").
32    
33    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
34        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
35        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
36        has an implication that the given string is incomplete (because a partial
37        match is preferred over a full match). For this reason, these items now
38        give a partial match in this situation. [Aside: previously, the one case
39        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
40        match rather than a full match, which was wrong by the old rules, but is
41        now correct.]
42    
43    6.  There was a bug in the handling of #-introduced comments, recognized when
44        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
45        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
46        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
47        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
48        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
49        places in pcre_compile().
50    
51    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
52        comments when looking ahead for named forward references to subpatterns,
53        the only newline sequence it recognized was NL. It now handles newlines
54        according to the set newline convention.
55    
56    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
57        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
58        cater for a lack of strerror(). These oversights have been fixed.
59    
60    9.  Added --match-limit and --recursion-limit to pcregrep.
61    
62    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
63    
64    11. When the -o option was used, pcregrep was setting a return code of 1, even
65        when matches were found, and --line-buffered was not being honoured.
66    
67    12. Added an optional parentheses number to the -o and --only-matching options
68        of pcregrep.
69    
70    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
71        can match an empty string. The code to do it in pcretest and pcredemo
72        needed fixing:
73    
74        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
75            only one byte after an empty string match just before CRLF (this case
76            just got forgotten; "any" and "anycrlf" were OK).
77    
78        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
79            mode when an empty string match preceded an ASCII character followed by
80            a non-ASCII character. (The code for advancing by one character rather
81            than one byte was nonsense.)
82    
83        (c) The pcredemo.c sample program did not have any code at all to handle
84            the cases when CRLF is a valid newline sequence.
85    
86    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
87        as a starting offset was within the subject string. There is now a new
88        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
89        negative or greater than the length of the string. In order to test this,
90        pcretest is extended to allow the setting of negative starting offsets.
91    
92    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
93        starting offset points to the beginning of a UTF-8 character was
94        unnecessarily clumsy. I tidied it up.
95    
96    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
97        bad UTF-8 sequence and one that is incomplete.
98    
99    17. Nobody had reported that the --include_dir option, which was added in
100        release 7.7 should have been called --include-dir (hyphen, not underscore)
101        for compatibility with GNU grep. I have changed it to --include-dir, but
102        left --include_dir as an undocumented synonym, and the same for
103        --exclude-dir, though that is not available in GNU grep, at least as of
104        release 2.5.4.
105    
106    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
107        characters from a string of bytes) have been redefined so as not to use
108        loops, in order to improve performance in some environments. At the same
109        time, I abstracted some of the common code into auxiliary macros to save
110        repetition (this should not affect the compiled code).
111    
112    
113    Version 8.10 25-Jun-2010
114    ------------------------
115    
116    1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
117        THEN.
118    
119    2.  (*ACCEPT) was not working when inside an atomic group.
120    
121    3.  Inside a character class, \B is treated as a literal by default, but
122        faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
123        causes the error). The code is unchanged, but I tidied the documentation.
124    
125    4.  Inside a character class, PCRE always treated \R and \X as literals,
126        whereas Perl faults them if its -w option is set. I have changed PCRE so
127        that it faults them when PCRE_EXTRA is set.
128    
129    5.  Added support for \N, which always matches any character other than
130        newline. (It is the same as "." when PCRE_DOTALL is not set.)
131    
132    6.  When compiling pcregrep with newer versions of gcc which may have
133        FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
134        declared with attribute warn_unused_result" were given. Just casting the
135        result to (void) does not stop the warnings; a more elaborate fudge is
136        needed. I've used a macro to implement this.
137    
138    7.  Minor change to pcretest.c to avoid a compiler warning.
139    
140    8.  Added four artifical Unicode properties to help with an option to make
141        \s etc use properties (see next item). The new properties are: Xan
142        (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
143    
144    9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
145        use Unicode properties. (*UCP) at the start of a pattern can be used to set
146        this option. Modified pcretest to add /W to test this facility. Added
147        REG_UCP to make it available via the POSIX interface.
148    
149    10. Added --line-buffered to pcregrep.
150    
151    11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
152        studied, and the match started with a letter with a code point greater than
153        127 whose first byte was different to the first byte of the other case of
154        the letter, the other case of this starting letter was not recognized
155        (#976).
156    
157    12. If a pattern that was studied started with a repeated Unicode property
158        test, for example, \p{Nd}+, there was the theoretical possibility of
159        setting up an incorrect bitmap of starting bytes, but fortunately it could
160        not have actually happened in practice until change 8 above was made (it
161        added property types that matched character-matching opcodes).
162    
163    13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
164        possible starting bytes for non-anchored patterns.
165    
166    14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
167        \R, and also a number of cases that involve Unicode properties, both
168        explicit and implicit when PCRE_UCP is set.
169    
170    15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
171        input, it could crash or give wrong results if characters with values
172        greater than 0xc0 were present in the subject string. (Detail: it assumed
173        UTF-8 input when processing these items.)
174    
175    16. Added a lot of (int) casts to avoid compiler warnings in systems where
176        size_t is 64-bit (#991).
177    
178    17. Added a check for running out of memory when PCRE is compiled with
179        --disable-stack-for-recursion (#990).
180    
181    18. If the last data line in a file for pcretest does not have a newline on
182        the end, a newline was missing in the output.
183    
184    19. The default pcre_chartables.c file recognizes only ASCII characters (values
185        less than 128) in its various bitmaps. However, there is a facility for
186        generating tables according to the current locale when PCRE is compiled. It
187        turns out that in some environments, 0x85 and 0xa0, which are Unicode space
188        characters, are recognized by isspace() and therefore were getting set in
189        these tables, and indeed these tables seem to approximate to ISO 8859. This
190        caused a problem in UTF-8 mode when pcre_study() was used to create a list
191        of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
192        which of course cannot start UTF-8 characters. I have changed the code so
193        that only real ASCII characters (less than 128) and the correct starting
194        bytes for UTF-8 encodings are set for characters greater than 127 when in
195        UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
196        altogether.)
197    
198    20. Added the /T option to pcretest so as to be able to run tests with non-
199        standard character tables, thus making it possible to include the tests
200        used for 19 above in the standard set of tests.
201    
202    21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
203        reference to a subpattern the other side of a comment that contains an
204        opening parenthesis caused either an internal compiling error, or a
205        reference to the wrong subpattern.
206    
207    
208    Version 8.02 19-Mar-2010
209    ------------------------
210    
211    1.  The Unicode data tables have been updated to Unicode 5.2.0.
212    
213    2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
214        configured.
215    
216    3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
217        original author of that file, following a query about its status.
218    
219    4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
220        inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
221    
222    5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
223        quantifier applied to a forward-referencing subroutine call, could compile
224        incorrect code or give the error "internal error: previously-checked
225        referenced subpattern not found".
226    
227    6.  Both MS Visual Studio and Symbian OS have problems with initializing
228        variables to point to external functions. For these systems, therefore,
229        pcre_malloc etc. are now initialized to local functions that call the
230        relevant global functions.
231    
232    7.  There were two entries missing in the vectors called coptable and poptable
233        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
234        I've fixed the data, and added a kludgy way of testing at compile time that
235        the lengths are correct (equal to the number of opcodes).
236    
237    8.  Following on from 7, I added a similar kludge to check the length of the
238        eint vector in pcreposix.c.
239    
240    9.  Error texts for pcre_compile() are held as one long string to avoid too
241        much relocation at load time. To find a text, the string is searched,
242        counting zeros. There was no check for running off the end of the string,
243        which could happen if a new error number was added without updating the
244        string.
245    
246    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
247    
248    11. \K was not working if it appeared in an atomic group or in a group that
249        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
250        \K is "not well defined" if used in an assertion. PCRE now accepts it if
251        the assertion is positive, but not if it is negative.
252    
253    12. Change 11 fortuitously reduced the size of the stack frame used in the
254        "match()" function of pcre_exec.c by one pointer. Forthcoming
255        implementation of support for (*MARK) will need an extra pointer on the
256        stack; I have reserved it now, so that the stack frame size does not
257        decrease.
258    
259    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
260        item in branch that calls a recursion is a subroutine call - as in the
261        second branch in the above example - was incorrectly given the compile-
262        time error "recursive call could loop indefinitely" because pcre_compile()
263        was not correctly checking the subroutine for matching a non-empty string.
264    
265    14. The checks for overrunning compiling workspace could trigger after an
266        overrun had occurred. This is a "should never occur" error, but it can be
267        triggered by pathological patterns such as hundreds of nested parentheses.
268        The checks now trigger 100 bytes before the end of the workspace.
269    
270    15. Fix typo in configure.ac: "srtoq" should be "strtoq".
271    
272    
273    Version 8.01 19-Jan-2010
274    ------------------------
275    
276    1.  If a pattern contained a conditional subpattern with only one branch (in
277        particular, this includes all (*DEFINE) patterns), a call to pcre_study()
278        computed the wrong minimum data length (which is of course zero for such
279        subpatterns). This could cause incorrect "no match" results.
280    
281    2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
282        the pattern is reset in the first branch, pcre_compile() failed with
283        "internal error: code overflow at offset...". This happened only when
284        the reset was to the original external option setting. (An optimization
285        abstracts leading options settings into an external setting, which was the
286        cause of this.)
287    
288    3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
289        of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
290        assertion pattern did not match (meaning that the assertion was true), it
291        was incorrectly treated as false if the SKIP had been reached during the
292        matching. This also applied to assertions used as conditions.
293    
294    4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
295        assertion subpattern, including such a pattern used as a condition,
296        unpredictable results occurred, instead of the error return
297        PCRE_ERROR_DFA_UITEM.
298    
299    5.  The C++ GlobalReplace function was not working like Perl for the special
300        situation when an empty string is matched. It now does the fancy magic
301        stuff that is necessary.
302    
303    6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
304        removed. (These were left over from very, very early versions of PCRE.)
305    
306    7.  Some cosmetic changes to the code to make life easier when compiling it
307        as part of something else:
308    
309        (a) Change DEBUG to PCRE_DEBUG.
310    
311        (b) In pcre_compile(), rename the member of the "branch_chain" structure
312            called "current" as "current_branch", to prevent a collision with the
313            Linux macro when compiled as a kernel module.
314    
315        (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
316            prevent a collision with the Linux macro when compiled as a kernel
317            module.
318    
319    8.  In pcre_compile() there are some checks for integer overflows that used to
320        cast potentially large values to (double). This has been changed to that
321        when building, a check for int64_t is made, and if it is found, it is used
322        instead, thus avoiding the use of floating point arithmetic. (There is no
323        other use of FP in PCRE.) If int64_t is not found, the fallback is to
324        double.
325    
326    9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
327        2005 (difference between two addresses compared to an unsigned value).
328    
329    10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
330        custom one, because of the following reported problem in Windows:
331    
332          - libbz2 uses the Pascal calling convention (WINAPI) for the functions
333              under Win32.
334          - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
335              therefore missing the function definition.
336          - The compiler thus generates a "C" signature for the test function.
337          - The linker fails to find the "C" function.
338          - PCRE fails to configure if asked to do so against libbz2.
339    
340    11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
341        messages were output:
342    
343          Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
344          rerunning libtoolize, to keep the correct libtool macros in-tree.
345          Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
346    
347        I have done both of these things.
348    
349    12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
350        most of the time, it *can* run out if it is given a pattern that contains a
351        runaway infinite recursion. I updated the discussion in the pcrestack man
352        page.
353    
354    13. Now that we have gone to the x.xx style of version numbers, the minor
355        version may start with zero. Using 08 or 09 is a bad idea because users
356        might check the value of PCRE_MINOR in their code, and 08 or 09 may be
357        interpreted as invalid octal numbers. I've updated the previous comment in
358        configure.ac, and also added a check that gives an error if 08 or 09 are
359        used.
360    
361    14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
362        causing partial matching to fail when the end of the subject matched \W
363        in a UTF-8 pattern where \W was quantified with a minimum of 3.
364    
365    15. There were some discrepancies between the declarations in pcre_internal.h
366        of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
367        their definitions. The declarations used "const uschar *" and the
368        definitions used USPTR. Even though USPTR is normally defined as "const
369        unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
370        reported that: "This difference in casting confuses some C++ compilers, for
371        example, SunCC recognizes above declarations as different functions and
372        generates broken code for hbpcre." I have changed the declarations to use
373        USPTR.
374    
375    16. GNU libtool is named differently on some systems. The autogen.sh script now
376        tries several variants such as glibtoolize (MacOSX) and libtoolize1x
377        (FreeBSD).
378    
379    17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
380        (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
381        comment: "Figure out how to create a longlong from a string: strtoll and
382        equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
383        instance, but it only takes 2 args instead of 3!"
384    
385    18. A subtle bug concerned with back references has been fixed by a change of
386        specification, with a corresponding code fix. A pattern such as
387        ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
388        refers, was giving matches when it shouldn't. For example, xa=xaaa would
389        match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
390        same bug. Such groups have to be quantified to be useful, or contained
391        inside another quantified group. (If there's no repetition, the reference
392        can never match.) The problem arises because, having left the group and
393        moved on to the rest of the pattern, a later failure that backtracks into
394        the group uses the captured value from the final iteration of the group
395        rather than the correct earlier one. I have fixed this in PCRE by forcing
396        any group that contains a reference to itself to be an atomic group; that
397        is, there cannot be any backtracking into it once it has completed. This is
398        similar to recursive and subroutine calls.
399    
400    
401    Version 8.00 19-Oct-09
402    ----------------------
403    
404    1.  The table for translating pcre_compile() error codes into POSIX error codes
405        was out-of-date, and there was no check on the pcre_compile() error code
406        being within the table. This could lead to an OK return being given in
407        error.
408    
409    2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
410        "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
411        in a Windows environment.
412    
413    3.  The pcregrep --count option prints the count for each file even when it is
414        zero, as does GNU grep. However, pcregrep was also printing all files when
415        --files-with-matches was added. Now, when both options are given, it prints
416        counts only for those files that have at least one match. (GNU grep just
417        prints the file name in this circumstance, but including the count seems
418        more useful - otherwise, why use --count?) Also ensured that the
419        combination -clh just lists non-zero counts, with no names.
420    
421    4.  The long form of the pcregrep -F option was incorrectly implemented as
422        --fixed_strings instead of --fixed-strings. This is an incompatible change,
423        but it seems right to fix it, and I didn't think it was worth preserving
424        the old behaviour.
425    
426    5.  The command line items --regex=pattern and --regexp=pattern were not
427        recognized by pcregrep, which required --regex pattern or --regexp pattern
428        (with a space rather than an '='). The man page documented the '=' forms,
429        which are compatible with GNU grep; these now work.
430    
431    6.  No libpcreposix.pc file was created for pkg-config; there was just
432        libpcre.pc and libpcrecpp.pc. The omission has been rectified.
433    
434    7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
435        when UCP support is not needed, by modifying the Python script that
436        generates it from Unicode data files. This should not matter if the module
437        is correctly used as a library, but I received one complaint about 50K of
438        unwanted data. My guess is that the person linked everything into his
439        program rather than using a library. Anyway, it does no harm.
440    
441    8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
442        was a minimum greater than 1 for a wide character in a possessive
443        repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
444        which had an unlimited repeat of a nested, fixed maximum repeat of a wide
445        character. Chaos in the form of incorrect output or a compiling loop could
446        result.
447    
448    9.  The restrictions on what a pattern can contain when partial matching is
449        requested for pcre_exec() have been removed. All patterns can now be
450        partially matched by this function. In addition, if there are at least two
451        slots in the offset vector, the offset of the earliest inspected character
452        for the match and the offset of the end of the subject are set in them when
453        PCRE_ERROR_PARTIAL is returned.
454    
455    10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
456        synonymous with PCRE_PARTIAL, for backwards compatibility, and
457        PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
458        and may be more useful for multi-segment matching.
459    
460    11. Partial matching with pcre_exec() is now more intuitive. A partial match
461        used to be given if ever the end of the subject was reached; now it is
462        given only if matching could not proceed because another character was
463        needed. This makes a difference in some odd cases such as Z(*FAIL) with the
464        string "Z", which now yields "no match" instead of "partial match". In the
465        case of pcre_dfa_exec(), "no match" is given if every matching path for the
466        final character ended with (*FAIL).
467    
468    12. Restarting a match using pcre_dfa_exec() after a partial match did not work
469        if the pattern had a "must contain" character that was already found in the
470        earlier partial match, unless partial matching was again requested. For
471        example, with the pattern /dog.(body)?/, the "must contain" character is
472        "g". If the first part-match was for the string "dog", restarting with
473        "sbody" failed. This bug has been fixed.
474    
475    13. The string returned by pcre_dfa_exec() after a partial match has been
476        changed so that it starts at the first inspected character rather than the
477        first character of the match. This makes a difference only if the pattern
478        starts with a lookbehind assertion or \b or \B (\K is not supported by
479        pcre_dfa_exec()). It's an incompatible change, but it makes the two
480        matching functions compatible, and I think it's the right thing to do.
481    
482    14. Added a pcredemo man page, created automatically from the pcredemo.c file,
483        so that the demonstration program is easily available in environments where
484        PCRE has not been installed from source.
485    
486    15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
487        libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
488        library.
489    
490    16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
491        It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
492        is not the first non-POSIX option to be added. Clearly some people find
493        these options useful.
494    
495    17. If a caller to the POSIX matching function regexec() passes a non-zero
496        value for nmatch with a NULL value for pmatch, the value of
497        nmatch is forced to zero.
498    
499    18. RunGrepTest did not have a test for the availability of the -u option of
500        the diff command, as RunTest does. It now checks in the same way as
501        RunTest, and also checks for the -b option.
502    
503    19. If an odd number of negated classes containing just a single character
504        interposed, within parentheses, between a forward reference to a named
505        subpattern and the definition of the subpattern, compilation crashed with
506        an internal error, complaining that it could not find the referenced
507        subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
508        [The bug was that it was starting one character too far in when skipping
509        over the character class, thus treating the ] as data rather than
510        terminating the class. This meant it could skip too much.]
511    
512    20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
513        /g option in pcretest when the pattern contains \K, which makes it possible
514        to have an empty string match not at the start, even when the pattern is
515        anchored. Updated pcretest and pcredemo to use this option.
516    
517    21. If the maximum number of capturing subpatterns in a recursion was greater
518        than the maximum at the outer level, the higher number was returned, but
519        with unset values at the outer level. The correct (outer level) value is
520        now given.
521    
522    22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
523        PCRE did not set those parentheses (unlike Perl). I have now found a way to
524        make it do so. The string so far is captured, making this feature
525        compatible with Perl.
526    
527    23. The tests have been re-organized, adding tests 11 and 12, to make it
528        possible to check the Perl 5.10 features against Perl 5.10.
529    
530    24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
531        pattern matches a fixed length string. PCRE did not allow this; now it
532        does. Neither allows recursion.
533    
534    25. I finally figured out how to implement a request to provide the minimum
535        length of subject string that was needed in order to match a given pattern.
536        (It was back references and recursion that I had previously got hung up
537        on.) This code has now been added to pcre_study(); it finds a lower bound
538        to the length of subject needed. It is not necessarily the greatest lower
539        bound, but using it to avoid searching strings that are too short does give
540        some useful speed-ups. The value is available to calling programs via
541        pcre_fullinfo().
542    
543    26. While implementing 25, I discovered to my embarrassment that pcretest had
544        not been passing the result of pcre_study() to pcre_dfa_exec(), so the
545        study optimizations had never been tested with that matching function.
546        Oops. What is worse, even when it was passed study data, there was a bug in
547        pcre_dfa_exec() that meant it never actually used it. Double oops. There
548        were also very few tests of studied patterns with pcre_dfa_exec().
549    
550    27. If (?| is used to create subpatterns with duplicate numbers, they are now
551        allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
552        on the other side of the coin, they are no longer allowed to have different
553        names, because these cannot be distinguished in PCRE, and this has caused
554        confusion. (This is a difference from Perl.)
555    
556    28. When duplicate subpattern names are present (necessarily with different
557        numbers, as required by 27 above), and a test is made by name in a
558        conditional pattern, either for a subpattern having been matched, or for
559        recursion in such a pattern, all the associated numbered subpatterns are
560        tested, and the overall condition is true if the condition is true for any
561        one of them. This is the way Perl works, and is also more like the way
562        testing by number works.
563    
564    
565    Version 7.9 11-Apr-09
566    ---------------------
567    
568    1.  When building with support for bzlib/zlib (pcregrep) and/or readline
569        (pcretest), all targets were linked against these libraries. This included
570        libpcre, libpcreposix, and libpcrecpp, even though they do not use these
571        libraries. This caused unwanted dependencies to be created. This problem
572        has been fixed, and now only pcregrep is linked with bzlib/zlib and only
573        pcretest is linked with readline.
574    
575    2.  The "typedef int BOOL" in pcre_internal.h that was included inside the
576        "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
577        moved outside it again, because FALSE and TRUE are already defined in AIX,
578        but BOOL is not.
579    
580    3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
581        PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
582    
583    4.  The pcregrep documentation said spaces were inserted as well as colons (or
584        hyphens) following file names and line numbers when outputting matching
585        lines. This is not true; no spaces are inserted. I have also clarified the
586        wording for the --colour (or --color) option.
587    
588    5.  In pcregrep, when --colour was used with -o, the list of matching strings
589        was not coloured; this is different to GNU grep, so I have changed it to be
590        the same.
591    
592    6.  When --colo(u)r was used in pcregrep, only the first matching substring in
593        each matching line was coloured. Now it goes on to look for further matches
594        of any of the test patterns, which is the same behaviour as GNU grep.
595    
596    7.  A pattern that could match an empty string could cause pcregrep to loop; it
597        doesn't make sense to accept an empty string match in pcregrep, so I have
598        locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
599        seems to be how GNU grep behaves.
600    
601    8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
602        start or after a newline", because the conditional assertion was not being
603        correctly handled. The rule now is that both the assertion and what follows
604        in the first alternative must satisfy the test.
605    
606    9.  If auto-callout was enabled in a pattern with a conditional group whose
607        condition was an assertion, PCRE could crash during matching, both with
608        pcre_exec() and pcre_dfa_exec().
609    
610    10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
611        used for matching.
612    
613    11. Unicode property support in character classes was not working for
614        characters (bytes) greater than 127 when not in UTF-8 mode.
615    
616    12. Added the -M command line option to pcretest.
617    
618    14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
619    
620    15. Added the PCRE_NO_START_OPTIMIZE match-time option.
621    
622    16. Added comments and documentation about mis-use of no_arg in the C++
623        wrapper.
624    
625    17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
626        from Martin Jerabek that uses macro names for all relevant character and
627        string constants.
628    
629    18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
630        SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
631        SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
632        these, but not everybody uses configure.
633    
634    19. A conditional group that had only one branch was not being correctly
635        recognized as an item that could match an empty string. This meant that an
636        enclosing group might also not be so recognized, causing infinite looping
637        (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
638        with the subject "ab", where knowledge that the repeated group can match
639        nothing is needed in order to break the loop.
640    
641    20. If a pattern that was compiled with callouts was matched using pcre_dfa_
642        exec(), but without supplying a callout function, matching went wrong.
643    
644    21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
645        leak if the size of the offset vector was greater than 30. When the vector
646        is smaller, the saved offsets during recursion go onto a local stack
647        vector, but for larger vectors malloc() is used. It was failing to free
648        when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
649        error, in fact).
650    
651    22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
652        heapframe that is used only when UTF-8 support is enabled. This caused no
653        problem, but was untidy.
654    
655    23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
656        CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
657        included within another project.
658    
659    24. Steven Van Ingelgem's patches to add more options to the CMake support,
660        slightly modified by me:
661    
662          (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
663              not building pcregrep.
664    
665          (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
666              if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
667    
668    25. Forward references, both numeric and by name, in patterns that made use of
669        duplicate group numbers, could behave incorrectly or give incorrect errors,
670        because when scanning forward to find the reference group, PCRE was not
671        taking into account the duplicate group numbers. A pattern such as
672        ^X(?3)(a)(?|(b)|(q))(Y) is an example.
673    
674    26. Changed a few more instances of "const unsigned char *" to USPTR, making
675        the feature of a custom pointer more persuasive (as requested by a user).
676    
677    27. Wrapped the definitions of fileno and isatty for Windows, which appear in
678        pcretest.c, inside #ifndefs, because it seems they are sometimes already
679        pre-defined.
680    
681    28. Added support for (*UTF8) at the start of a pattern.
682    
683    29. Arrange for flags added by the "release type" setting in CMake to be shown
684        in the configuration summary.
685    
686    
687    Version 7.8 05-Sep-08
688  ---------------------  ---------------------
689    
690  1.  Replaced UCP searching code with optimized version as implemented for Ad  1.  Replaced UCP searching code with optimized version as implemented for Ad
# Line 75  Version 7.8 25-Aug-08 Line 758  Version 7.8 25-Aug-08
758    
759  19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as  19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
760      supplied by Stefan Weber. I made a further small update for 7.8 because      supplied by Stefan Weber. I made a further small update for 7.8 because
761      there is a change of source arrangements: the pcre_searchfuncs.c module is      there is a change of source arrangements: the pcre_searchfuncs.c module is
762      replaced by pcre_ucd.c.      replaced by pcre_ucd.c.
763    
764    
765  Version 7.7 07-May-08  Version 7.7 07-May-08

Legend:
Removed from v.373  
changed lines
  Added in v.573

webmaster@exim.org
ViewVC Help
Powered by ViewVC 1.1.12