/[pcre]/code/tags/pcre-8.01/ChangeLog
ViewVC logotype

Diff of /code/tags/pcre-8.01/ChangeLog

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

revision 448 by ph10, Tue Sep 15 19:11:48 2009 UTC revision 476 by ph10, Sun Jan 3 15:37:24 2010 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 8.00 ??-???-??  Version 8.01 11-Dec-09
5    ----------------------
6    
7    1.  If a pattern contained a conditional subpattern with only one branch (in
8        particular, this includes all (DEFINE) patterns), a call to pcre_study()
9        computed the wrong minimum data length (which is of course zero for such
10        subpatterns).
11    
12    2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
13        the pattern is reset in the first branch, pcre_compile() failed with
14        "internal error: code overflow at offset...". This happened only when
15        the reset was to the original external option setting. (An optimization
16        abstracts leading options settings into an external setting, which was the
17        cause of this.)
18    
19    3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
20        of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
21        assertion pattern did not match (meaning that the assertion was true), it
22        was incorrectly treated as false if the SKIP had been reached during the
23        matching. This also applied to assertions used as conditions.
24    
25    4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
26        assertion subpattern, including such a pattern used as a condition,
27        unpredictable results occurred, instead of the error return
28        PCRE_ERROR_DFA_UITEM.
29    
30    5.  The C++ GlobalReplace function was not working like Perl for the special
31        situation when an empty string is matched. It now does the fancy magic
32        stuff that is necessary.
33    
34    6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
35        removed. (These were left over from very, very early versions of PCRE.)
36    
37    7.  Some cosmetic changes to the code to make life easier when compiling it
38        as part of something else:
39    
40        (a) Change DEBUG to PCRE_DEBUG.
41    
42        (b) In pcre_compile(), rename the member of the "branch_chain" structure
43            called "current" as "current_branch", to prevent a collision with the
44            Linux macro when compiled as a kernel module.
45    
46        (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
47            prevent a collision with the Linux macro when compiled as a kernel
48            module.
49    
50    8.  In pcre_compile() there are some checks for integer overflows that used to
51        cast potentially large values to (double). This has been changed to that
52        when building, a check for int64_t is made, and if it is found, it is used
53        instead, thus avoiding the use of floating point arithmetic. (There is no
54        other use of FP in PCRE.) If int64_t is not found, the fallback is to
55        double.
56    
57    9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
58        2005 (difference between two addresses compared to an unsigned value).
59    
60    
61    
62    Version 8.00 19-Oct-09
63  ----------------------  ----------------------
64    
65  1.  The table for translating pcre_compile() error codes into POSIX error codes  1.  The table for translating pcre_compile() error codes into POSIX error codes
66      was out-of-date, and there was no check on the pcre_compile() error code      was out-of-date, and there was no check on the pcre_compile() error code
67      being within the table. This could lead to an OK return being given in      being within the table. This could lead to an OK return being given in
68      error.      error.
69    
70  2.  Changed the call to open a subject file in pcregrep from fopen(pathname,  2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
71      "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests      "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
72      in a Windows environment.      in a Windows environment.
73    
74  3.  The pcregrep --count option prints the count for each file even when it is  3.  The pcregrep --count option prints the count for each file even when it is
75      zero, as does GNU grep. However, pcregrep was also printing all files when      zero, as does GNU grep. However, pcregrep was also printing all files when
76      --files-with-matches was added. Now, when both options are given, it prints      --files-with-matches was added. Now, when both options are given, it prints
77      counts only for those files that have at least one match. (GNU grep just      counts only for those files that have at least one match. (GNU grep just
78      prints the file name in this circumstance, but including the count seems      prints the file name in this circumstance, but including the count seems
79      more useful - otherwise, why use --count?) Also ensured that the      more useful - otherwise, why use --count?) Also ensured that the
80      combination -clh just lists non-zero counts, with no names.      combination -clh just lists non-zero counts, with no names.
81    
82  4.  The long form of the pcregrep -F option was incorrectly implemented as  4.  The long form of the pcregrep -F option was incorrectly implemented as
83      --fixed_strings instead of --fixed-strings. This is an incompatible change,      --fixed_strings instead of --fixed-strings. This is an incompatible change,
84      but it seems right to fix it, and I didn't think it was worth preserving      but it seems right to fix it, and I didn't think it was worth preserving
85      the old behaviour.      the old behaviour.
86    
87  5.  The command line items --regex=pattern and --regexp=pattern were not  5.  The command line items --regex=pattern and --regexp=pattern were not
88      recognized by pcregrep, which required --regex pattern or --regexp pattern      recognized by pcregrep, which required --regex pattern or --regexp pattern
89      (with a space rather than an '='). The man page documented the '=' forms,      (with a space rather than an '='). The man page documented the '=' forms,
90      which are compatible with GNU grep; these now work.      which are compatible with GNU grep; these now work.
91    
92  6.  No libpcreposix.pc file was created for pkg-config; there was just  6.  No libpcreposix.pc file was created for pkg-config; there was just
93      libpcre.pc and libpcrecpp.pc. The omission has been rectified.      libpcre.pc and libpcrecpp.pc. The omission has been rectified.
94    
95  7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size  7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
96      when UCP support is not needed, by modifying the Python script that      when UCP support is not needed, by modifying the Python script that
97      generates it from Unicode data files. This should not matter if the module      generates it from Unicode data files. This should not matter if the module
98      is correctly used as a library, but I received one complaint about 50K of      is correctly used as a library, but I received one complaint about 50K of
99      unwanted data. My guess is that the person linked everything into his      unwanted data. My guess is that the person linked everything into his
100      program rather than using a library. Anyway, it does no harm.      program rather than using a library. Anyway, it does no harm.
101    
102  8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger  8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
103      was a minimum greater than 1 for a wide character in a possessive      was a minimum greater than 1 for a wide character in a possessive
104      repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8      repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
105      which had an unlimited repeat of a nested, fixed maximum repeat of a wide      which had an unlimited repeat of a nested, fixed maximum repeat of a wide
106      character. Chaos in the form of incorrect output or a compiling loop could      character. Chaos in the form of incorrect output or a compiling loop could
107      result.      result.
108    
109  9.  The restrictions on what a pattern can contain when partial matching is  9.  The restrictions on what a pattern can contain when partial matching is
110      requested for pcre_exec() have been removed. All patterns can now be      requested for pcre_exec() have been removed. All patterns can now be
111      partially matched by this function. In addition, if there are at least two      partially matched by this function. In addition, if there are at least two
112      slots in the offset vector, the offset of the earliest inspected character      slots in the offset vector, the offset of the earliest inspected character
113      for the match and the offset of the end of the subject are set in them when      for the match and the offset of the end of the subject are set in them when
114      PCRE_ERROR_PARTIAL is returned.      PCRE_ERROR_PARTIAL is returned.
115    
116  10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is  10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
117      synonymous with PCRE_PARTIAL, for backwards compatibility, and      synonymous with PCRE_PARTIAL, for backwards compatibility, and
118      PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,      PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
119      and may be more useful for multi-segment matching, especially with      and may be more useful for multi-segment matching.
120      pcre_exec().  
121    11. Partial matching with pcre_exec() is now more intuitive. A partial match
122  11. Partial matching with pcre_exec() is now more intuitive. A partial match      used to be given if ever the end of the subject was reached; now it is
123      used to be given if ever the end of the subject was reached; now it is      given only if matching could not proceed because another character was
124      given only if matching could not proceed because another character was      needed. This makes a difference in some odd cases such as Z(*FAIL) with the
125      needed. This makes a difference in some odd cases such as Z(*FAIL) with the      string "Z", which now yields "no match" instead of "partial match". In the
126      string "Z", which now yields "no match" instead of "partial match". In the      case of pcre_dfa_exec(), "no match" is given if every matching path for the
127      case of pcre_dfa_exec(), "no match" is given if every matching path for the      final character ended with (*FAIL).
128      final character ended with (*FAIL).  
   
129  12. Restarting a match using pcre_dfa_exec() after a partial match did not work  12. Restarting a match using pcre_dfa_exec() after a partial match did not work
130      if the pattern had a "must contain" character that was already found in the      if the pattern had a "must contain" character that was already found in the
131      earlier partial match, unless partial matching was again requested. For      earlier partial match, unless partial matching was again requested. For
132      example, with the pattern /dog.(body)?/, the "must contain" character is      example, with the pattern /dog.(body)?/, the "must contain" character is
133      "g". If the first part-match was for the string "dog", restarting with      "g". If the first part-match was for the string "dog", restarting with
134      "sbody" failed. This bug has been fixed.      "sbody" failed. This bug has been fixed.
135    
136  13. The string returned by pcre_dfa_exec() after a partial match has been  13. The string returned by pcre_dfa_exec() after a partial match has been
137      changed so that it starts at the first inspected character rather than the      changed so that it starts at the first inspected character rather than the
138      first character of the match. This makes a difference only if the pattern      first character of the match. This makes a difference only if the pattern
139      starts with a lookbehind assertion or \b or \B (\K is not supported by      starts with a lookbehind assertion or \b or \B (\K is not supported by
140      pcre_dfa_exec()). It's an incompatible change, but it makes the two      pcre_dfa_exec()). It's an incompatible change, but it makes the two
141      matching functions compatible, and I think it's the right thing to do.      matching functions compatible, and I think it's the right thing to do.
142    
143  14. Added a pcredemo man page, created automatically from the pcredemo.c file,  14. Added a pcredemo man page, created automatically from the pcredemo.c file,
144      so that the demonstration program is easily available in environments where      so that the demonstration program is easily available in environments where
145      PCRE has not been installed from source.      PCRE has not been installed from source.
146    
147  15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,  15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
148      libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared      libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
149      library.      library.
150    
151  16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.  16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
152      It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it      It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
153      is not the first non-POSIX option to be added. Clearly some people find      is not the first non-POSIX option to be added. Clearly some people find
154      these options useful.      these options useful.
155    
156  17. If a caller to the POSIX matching function regexec() passes a non-zero  17. If a caller to the POSIX matching function regexec() passes a non-zero
157      value for nmatch with a NULL value for pmatch, the value of      value for nmatch with a NULL value for pmatch, the value of
158      nmatch is forced to zero.      nmatch is forced to zero.
159    
160  18. RunGrepTest did not have a test for the availability of the -u option of  18. RunGrepTest did not have a test for the availability of the -u option of
161      the diff command, as RunTest does. It now checks in the same way as      the diff command, as RunTest does. It now checks in the same way as
162      RunTest, and also checks for the -b option.      RunTest, and also checks for the -b option.
163    
164  19. If an odd number of negated classes containing just a single character  19. If an odd number of negated classes containing just a single character
165      interposed, within parentheses, between a forward reference to a named      interposed, within parentheses, between a forward reference to a named
166      subpattern and the definition of the subpattern, compilation crashed with      subpattern and the definition of the subpattern, compilation crashed with
167      an internal error, complaining that it could not find the referenced      an internal error, complaining that it could not find the referenced
168      subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.      subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
169      [The bug was that it was starting one character too far in when skipping      [The bug was that it was starting one character too far in when skipping
170      over the character class, thus treating the ] as data rather than      over the character class, thus treating the ] as data rather than
171      terminating the class. This meant it could skip too much.]      terminating the class. This meant it could skip too much.]
172    
173  20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the  20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
174      /g option in pcretest when the pattern contains \K, which makes it possible      /g option in pcretest when the pattern contains \K, which makes it possible
175      to have an empty string match not at the start, even when the pattern is      to have an empty string match not at the start, even when the pattern is
176      anchored. Updated pcretest and pcredemo to use this option.      anchored. Updated pcretest and pcredemo to use this option.
177    
178  21. If the maximum number of capturing subpatterns in a recursion was greater  21. If the maximum number of capturing subpatterns in a recursion was greater
179      than the maximum at the outer level, the higher number was returned, but      than the maximum at the outer level, the higher number was returned, but
180      with unset values at the outer level. The correct (outer level) value is      with unset values at the outer level. The correct (outer level) value is
181      now given.      now given.
182    
183  22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of  22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
184      PCRE did not set those parentheses (unlike Perl). I have now found a way to      PCRE did not set those parentheses (unlike Perl). I have now found a way to
185      make it do so. The string so far is captured, making this feature      make it do so. The string so far is captured, making this feature
186      compatible with Perl.      compatible with Perl.
187    
188  23. The tests have been re-organized, adding tests 11 and 12, to make it  23. The tests have been re-organized, adding tests 11 and 12, to make it
189      possible to check the Perl 5.10 features against Perl 5.10.      possible to check the Perl 5.10 features against Perl 5.10.
190    
191    24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
192        pattern matches a fixed length string. PCRE did not allow this; now it
193        does. Neither allows recursion.
194    
195    25. I finally figured out how to implement a request to provide the minimum
196        length of subject string that was needed in order to match a given pattern.
197        (It was back references and recursion that I had previously got hung up
198        on.) This code has now been added to pcre_study(); it finds a lower bound
199        to the length of subject needed. It is not necessarily the greatest lower
200        bound, but using it to avoid searching strings that are too short does give
201        some useful speed-ups. The value is available to calling programs via
202        pcre_fullinfo().
203    
204    26. While implementing 25, I discovered to my embarrassment that pcretest had
205        not been passing the result of pcre_study() to pcre_dfa_exec(), so the
206        study optimizations had never been tested with that matching function.
207        Oops. What is worse, even when it was passed study data, there was a bug in
208        pcre_dfa_exec() that meant it never actually used it. Double oops. There
209        were also very few tests of studied patterns with pcre_dfa_exec().
210    
211    27. If (?| is used to create subpatterns with duplicate numbers, they are now
212        allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
213        on the other side of the coin, they are no longer allowed to have different
214        names, because these cannot be distinguished in PCRE, and this has caused
215        confusion. (This is a difference from Perl.)
216    
217    28. When duplicate subpattern names are present (necessarily with different
218        numbers, as required by 27 above), and a test is made by name in a
219        conditional pattern, either for a subpattern having been matched, or for
220        recursion in such a pattern, all the associated numbered subpatterns are
221        tested, and the overall condition is true if the condition is true for any
222        one of them. This is the way Perl works, and is also more like the way
223        testing by number works.
224    
225    
226  Version 7.9 11-Apr-09  Version 7.9 11-Apr-09
227  ---------------------  ---------------------

Legend:
Removed from v.448  
changed lines
  Added in v.476

webmaster@exim.org
ViewVC Help
Powered by ViewVC 1.1.12