ViewVC logotype

Diff of /code/trunk/ChangeLog

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

revision 405 by ph10, Mon Mar 23 12:05:20 2009 UTC revision 505 by ph10, Tue Mar 9 16:50:47 2010 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
4  Version 7.9 xx-xxx-09  Version 8.02 01-Mar-2010
5    ------------------------
7    1.  The Unicode data tables have been updated to Unicode 5.2.0.
9    2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
10        configured.
12    3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
13        original author of that file, following a query about its status.
15    4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
16        inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
18    5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
19        quantifier applied to a forward-referencing subroutine call, could compile
20        incorrect code or give the error "internal error: previously-checked
21        referenced subpattern not found".
23    6.  Both MS Visual Studio and Symbian OS have problems with initializing
24        variables to point to external functions. For these systems, therefore,
25        pcre_malloc etc. are now initialized to local functions that call the
26        relevant global functions.
28    7.  There were two entries missing in the vectors called coptable and poptable
29        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
30        I've fixed the data, and added a kludgy way of testing at compile time that
31        the lengths are correct (equal to the number of opcodes).
33    8.  Following on from 7, I added a similar kludge to check the length of the
34        eint vector in pcreposix.c.
36    9.  Error texts for pcre_compile() are held as one long string to avoid too
37        much relocation at load time. To find a text, the string is searched,
38        counting zeros. There was no check for running off the end of the string,
39        which could happen if a new error number was added without updating the
40        string.
42    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
44    11. \K was not working if it appeared in an atomic group or in a group that
45        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
46        \K is "not well defined" if used in an assertion. PCRE now accepts it if
47        the assertion is positive, but not if it is negative.
49    12. Change 11 fortuitously reduced the size of the stack frame used in the
50        "match()" function of pcre_exec.c by one pointer. Forthcoming
51        implementation of support for (*MARK) will need an extra pointer on the
52        stack; I have reserved it now, so that the stack frame size does not
53        decrease.
55    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
56        item in branch that calls a recursion is a subroutine call - as in the
57        second branch in the above example - was incorrectly given the compile-
58        time error "recursive call could loop indefinitely" because pcre_compile()
59        was not correctly checking the subroutine for matching a non-empty string.
61    14. The checks for overrunning compiling workspace could trigger after an
62        overrun had occurred. This is a "should never occur" error, but it can be
63        triggered by pathological patterns such as hundreds of nested parentheses.
64        The checks now trigger 100 bytes before the end of the workspace.
67    Version 8.01 19-Jan-2010
68    ------------------------
70    1.  If a pattern contained a conditional subpattern with only one branch (in
71        particular, this includes all (*DEFINE) patterns), a call to pcre_study()
72        computed the wrong minimum data length (which is of course zero for such
73        subpatterns). This could cause incorrect "no match" results.
75    2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
76        the pattern is reset in the first branch, pcre_compile() failed with
77        "internal error: code overflow at offset...". This happened only when
78        the reset was to the original external option setting. (An optimization
79        abstracts leading options settings into an external setting, which was the
80        cause of this.)
82    3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
83        of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
84        assertion pattern did not match (meaning that the assertion was true), it
85        was incorrectly treated as false if the SKIP had been reached during the
86        matching. This also applied to assertions used as conditions.
88    4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
89        assertion subpattern, including such a pattern used as a condition,
90        unpredictable results occurred, instead of the error return
93    5.  The C++ GlobalReplace function was not working like Perl for the special
94        situation when an empty string is matched. It now does the fancy magic
95        stuff that is necessary.
97    6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
98        removed. (These were left over from very, very early versions of PCRE.)
100    7.  Some cosmetic changes to the code to make life easier when compiling it
101        as part of something else:
103        (a) Change DEBUG to PCRE_DEBUG.
105        (b) In pcre_compile(), rename the member of the "branch_chain" structure
106            called "current" as "current_branch", to prevent a collision with the
107            Linux macro when compiled as a kernel module.
109        (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
110            prevent a collision with the Linux macro when compiled as a kernel
111            module.
113    8.  In pcre_compile() there are some checks for integer overflows that used to
114        cast potentially large values to (double). This has been changed to that
115        when building, a check for int64_t is made, and if it is found, it is used
116        instead, thus avoiding the use of floating point arithmetic. (There is no
117        other use of FP in PCRE.) If int64_t is not found, the fallback is to
118        double.
120    9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
121        2005 (difference between two addresses compared to an unsigned value).
123    10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
124        custom one, because of the following reported problem in Windows:
126          - libbz2 uses the Pascal calling convention (WINAPI) for the functions
127              under Win32.
128          - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
129              therefore missing the function definition.
130          - The compiler thus generates a "C" signature for the test function.
131          - The linker fails to find the "C" function.
132          - PCRE fails to configure if asked to do so against libbz2.
134    11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
135        messages were output:
137          Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
138          rerunning libtoolize, to keep the correct libtool macros in-tree.
139          Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
141        I have done both of these things.
143    12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
144        most of the time, it *can* run out if it is given a pattern that contains a
145        runaway infinite recursion. I updated the discussion in the pcrestack man
146        page.
148    13. Now that we have gone to the x.xx style of version numbers, the minor
149        version may start with zero. Using 08 or 09 is a bad idea because users
150        might check the value of PCRE_MINOR in their code, and 08 or 09 may be
151        interpreted as invalid octal numbers. I've updated the previous comment in
152        configure.ac, and also added a check that gives an error if 08 or 09 are
153        used.
155    14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
156        causing partial matching to fail when the end of the subject matched \W
157        in a UTF-8 pattern where \W was quantified with a minimum of 3.
159    15. There were some discrepancies between the declarations in pcre_internal.h
160        of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
161        their definitions. The declarations used "const uschar *" and the
162        definitions used USPTR. Even though USPTR is normally defined as "const
163        unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
164        reported that: "This difference in casting confuses some C++ compilers, for
165        example, SunCC recognizes above declarations as different functions and
166        generates broken code for hbpcre." I have changed the declarations to use
167        USPTR.
169    16. GNU libtool is named differently on some systems. The autogen.sh script now
170        tries several variants such as glibtoolize (MacOSX) and libtoolize1x
171        (FreeBSD).
173    17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
174        (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
175        comment: "Figure out how to create a longlong from a string: strtoll and
176        equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
177        instance, but it only takes 2 args instead of 3!"
179    18. A subtle bug concerned with back references has been fixed by a change of
180        specification, with a corresponding code fix. A pattern such as
181        ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
182        refers, was giving matches when it shouldn't. For example, xa=xaaa would
183        match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
184        same bug. Such groups have to be quantified to be useful, or contained
185        inside another quantified group. (If there's no repetition, the reference
186        can never match.) The problem arises because, having left the group and
187        moved on to the rest of the pattern, a later failure that backtracks into
188        the group uses the captured value from the final iteration of the group
189        rather than the correct earlier one. I have fixed this in PCRE by forcing
190        any group that contains a reference to itself to be an atomic group; that
191        is, there cannot be any backtracking into it once it has completed. This is
192        similar to recursive and subroutine calls.
195    Version 8.00 19-Oct-09
196    ----------------------
198    1.  The table for translating pcre_compile() error codes into POSIX error codes
199        was out-of-date, and there was no check on the pcre_compile() error code
200        being within the table. This could lead to an OK return being given in
201        error.
203    2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
204        "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
205        in a Windows environment.
207    3.  The pcregrep --count option prints the count for each file even when it is
208        zero, as does GNU grep. However, pcregrep was also printing all files when
209        --files-with-matches was added. Now, when both options are given, it prints
210        counts only for those files that have at least one match. (GNU grep just
211        prints the file name in this circumstance, but including the count seems
212        more useful - otherwise, why use --count?) Also ensured that the
213        combination -clh just lists non-zero counts, with no names.
215    4.  The long form of the pcregrep -F option was incorrectly implemented as
216        --fixed_strings instead of --fixed-strings. This is an incompatible change,
217        but it seems right to fix it, and I didn't think it was worth preserving
218        the old behaviour.
220    5.  The command line items --regex=pattern and --regexp=pattern were not
221        recognized by pcregrep, which required --regex pattern or --regexp pattern
222        (with a space rather than an '='). The man page documented the '=' forms,
223        which are compatible with GNU grep; these now work.
225    6.  No libpcreposix.pc file was created for pkg-config; there was just
226        libpcre.pc and libpcrecpp.pc. The omission has been rectified.
228    7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
229        when UCP support is not needed, by modifying the Python script that
230        generates it from Unicode data files. This should not matter if the module
231        is correctly used as a library, but I received one complaint about 50K of
232        unwanted data. My guess is that the person linked everything into his
233        program rather than using a library. Anyway, it does no harm.
235    8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
236        was a minimum greater than 1 for a wide character in a possessive
237        repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
238        which had an unlimited repeat of a nested, fixed maximum repeat of a wide
239        character. Chaos in the form of incorrect output or a compiling loop could
240        result.
242    9.  The restrictions on what a pattern can contain when partial matching is
243        requested for pcre_exec() have been removed. All patterns can now be
244        partially matched by this function. In addition, if there are at least two
245        slots in the offset vector, the offset of the earliest inspected character
246        for the match and the offset of the end of the subject are set in them when
247        PCRE_ERROR_PARTIAL is returned.
249    10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
250        synonymous with PCRE_PARTIAL, for backwards compatibility, and
251        PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
252        and may be more useful for multi-segment matching.
254    11. Partial matching with pcre_exec() is now more intuitive. A partial match
255        used to be given if ever the end of the subject was reached; now it is
256        given only if matching could not proceed because another character was
257        needed. This makes a difference in some odd cases such as Z(*FAIL) with the
258        string "Z", which now yields "no match" instead of "partial match". In the
259        case of pcre_dfa_exec(), "no match" is given if every matching path for the
260        final character ended with (*FAIL).
262    12. Restarting a match using pcre_dfa_exec() after a partial match did not work
263        if the pattern had a "must contain" character that was already found in the
264        earlier partial match, unless partial matching was again requested. For
265        example, with the pattern /dog.(body)?/, the "must contain" character is
266        "g". If the first part-match was for the string "dog", restarting with
267        "sbody" failed. This bug has been fixed.
269    13. The string returned by pcre_dfa_exec() after a partial match has been
270        changed so that it starts at the first inspected character rather than the
271        first character of the match. This makes a difference only if the pattern
272        starts with a lookbehind assertion or \b or \B (\K is not supported by
273        pcre_dfa_exec()). It's an incompatible change, but it makes the two
274        matching functions compatible, and I think it's the right thing to do.
276    14. Added a pcredemo man page, created automatically from the pcredemo.c file,
277        so that the demonstration program is easily available in environments where
278        PCRE has not been installed from source.
280    15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
281        libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
282        library.
284    16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
285        It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
286        is not the first non-POSIX option to be added. Clearly some people find
287        these options useful.
289    17. If a caller to the POSIX matching function regexec() passes a non-zero
290        value for nmatch with a NULL value for pmatch, the value of
291        nmatch is forced to zero.
293    18. RunGrepTest did not have a test for the availability of the -u option of
294        the diff command, as RunTest does. It now checks in the same way as
295        RunTest, and also checks for the -b option.
297    19. If an odd number of negated classes containing just a single character
298        interposed, within parentheses, between a forward reference to a named
299        subpattern and the definition of the subpattern, compilation crashed with
300        an internal error, complaining that it could not find the referenced
301        subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
302        [The bug was that it was starting one character too far in when skipping
303        over the character class, thus treating the ] as data rather than
304        terminating the class. This meant it could skip too much.]
306    20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
307        /g option in pcretest when the pattern contains \K, which makes it possible
308        to have an empty string match not at the start, even when the pattern is
309        anchored. Updated pcretest and pcredemo to use this option.
311    21. If the maximum number of capturing subpatterns in a recursion was greater
312        than the maximum at the outer level, the higher number was returned, but
313        with unset values at the outer level. The correct (outer level) value is
314        now given.
316    22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
317        PCRE did not set those parentheses (unlike Perl). I have now found a way to
318        make it do so. The string so far is captured, making this feature
319        compatible with Perl.
321    23. The tests have been re-organized, adding tests 11 and 12, to make it
322        possible to check the Perl 5.10 features against Perl 5.10.
324    24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
325        pattern matches a fixed length string. PCRE did not allow this; now it
326        does. Neither allows recursion.
328    25. I finally figured out how to implement a request to provide the minimum
329        length of subject string that was needed in order to match a given pattern.
330        (It was back references and recursion that I had previously got hung up
331        on.) This code has now been added to pcre_study(); it finds a lower bound
332        to the length of subject needed. It is not necessarily the greatest lower
333        bound, but using it to avoid searching strings that are too short does give
334        some useful speed-ups. The value is available to calling programs via
335        pcre_fullinfo().
337    26. While implementing 25, I discovered to my embarrassment that pcretest had
338        not been passing the result of pcre_study() to pcre_dfa_exec(), so the
339        study optimizations had never been tested with that matching function.
340        Oops. What is worse, even when it was passed study data, there was a bug in
341        pcre_dfa_exec() that meant it never actually used it. Double oops. There
342        were also very few tests of studied patterns with pcre_dfa_exec().
344    27. If (?| is used to create subpatterns with duplicate numbers, they are now
345        allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
346        on the other side of the coin, they are no longer allowed to have different
347        names, because these cannot be distinguished in PCRE, and this has caused
348        confusion. (This is a difference from Perl.)
350    28. When duplicate subpattern names are present (necessarily with different
351        numbers, as required by 27 above), and a test is made by name in a
352        conditional pattern, either for a subpattern having been matched, or for
353        recursion in such a pattern, all the associated numbered subpatterns are
354        tested, and the overall condition is true if the condition is true for any
355        one of them. This is the way Perl works, and is also more like the way
356        testing by number works.
359    Version 7.9 11-Apr-09
360  ---------------------  ---------------------
362  1.  When building with support for bzlib/zlib (pcregrep) and/or readline  1.  When building with support for bzlib/zlib (pcregrep) and/or readline
# Line 17  Version 7.9 xx-xxx-09 Line 372  Version 7.9 xx-xxx-09
372      but BOOL is not.      but BOOL is not.
374  3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and  3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
375      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.
377  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
378      hyphens) following file names and line numbers when outputting matching      hyphens) following file names and line numbers when outputting matching
# Line 95  Version 7.9 xx-xxx-09 Line 450  Version 7.9 xx-xxx-09
450      CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is      CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
451      included within another project.      included within another project.
453    24. Steven Van Ingelgem's patches to add more options to the CMake support,
454        slightly modified by me:
456          (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
457              not building pcregrep.
459          (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
460              if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
462    25. Forward references, both numeric and by name, in patterns that made use of
463        duplicate group numbers, could behave incorrectly or give incorrect errors,
464        because when scanning forward to find the reference group, PCRE was not
465        taking into account the duplicate group numbers. A pattern such as
466        ^X(?3)(a)(?|(b)|(q))(Y) is an example.
468    26. Changed a few more instances of "const unsigned char *" to USPTR, making
469        the feature of a custom pointer more persuasive (as requested by a user).
471    27. Wrapped the definitions of fileno and isatty for Windows, which appear in
472        pcretest.c, inside #ifndefs, because it seems they are sometimes already
473        pre-defined.
475    28. Added support for (*UTF8) at the start of a pattern.
477    29. Arrange for flags added by the "release type" setting in CMake to be shown
478        in the configuration summary.
481  Version 7.8 05-Sep-08  Version 7.8 05-Sep-08

Removed from v.405  
changed lines
  Added in v.505

  ViewVC Help
Powered by ViewVC 1.1.5