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

Diff of /code/trunk/ChangeLog

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

revision 118 by ph10, Fri Mar 9 16:17:46 2007 UTC revision 261 by ph10, Fri Sep 21 08:37:48 2007 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 7.1 05-Mar-07  Version 7.4 21-Sep-07
5    ---------------------
6    
7    1.  Change 7.3/28 was implemented for classes by looking at the bitmap. This
8        means that a class such as [\s] counted as "explicit reference to CR or
9        LF". That isn't really right - the whole point of the change was to try to
10        help when there was an actual mention of one of the two characters. So now
11        the change happens only if \r or \n (or a literal CR or LF) character is
12        encountered.
13    
14    2.  The 32-bit options word was also used for 6 internal flags, but the numbers
15        of both had grown to the point where there were only 3 bits left.
16        Fortunately, there was spare space in the data structure, and so I have
17        moved the internal flags into a new 16-bit field to free up more option
18        bits.
19    
20    3.  The appearance of (?J) at the start of a pattern set the DUPNAMES option,
21        but did not set the internal JCHANGED flag - either of these is enough to
22        control the way the "get" function works - but the PCRE_INFO_JCHANGED
23        facility is supposed to tell if (?J) was ever used, so now (?J) at the
24        start sets both bits.
25    
26    4.  Added options (at build time, compile time, exec time) to change \R from
27        matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
28    
29    5.  doc/pcresyntax.html was missing from the distribution.
30    
31    6.  Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
32        compatibility, even though it is no longer used.
33    
34    7.  Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
35        strtoull to pcrecpp.cc to select the available functions in WIN32 when the
36        windows.h file is present (where different names are used). [This was
37        reversed later after testing - see 16 below.]
38    
39    8.  Changed all #include <config.h> to #include "config.h". There were also
40        some further <pcre.h> cases that I changed to "pcre.h".
41    
42    9.  When pcregrep was used with the --colour option, it missed the line ending
43        sequence off the lines that it output.
44    
45    10. It was pointed out to me that arrays of string pointers cause lots of
46        relocations when a shared library is dynamically loaded. A technique of
47        using a single long string with a table of offsets can drastically reduce
48        these. I have refactored PCRE in four places to do this. The result is
49        dramatic:
50    
51          Originally:                          290
52          After changing UCP table:            187
53          After changing error message table:   43
54          After changing table of "verbs"       36
55          After changing table of Posix names   22
56    
57        Thanks to the folks working on Gregex for glib for this insight.
58    
59    11. --disable-stack-for-recursion caused compiling to fail unless -enable-
60        unicode-properties was also set.
61    
62    12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
63    
64    13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
65        checked only for CRLF.
66    
67    14. Added casts to pcretest.c to avoid compiler warnings.
68    
69    15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
70    
71    16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
72        and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
73        entirely. This removes changes made in 7 above.
74    
75    17. The CMake files have been updated, and there is now more information about
76        building with CMake in the NON-UNIX-USE document.
77    
78    
79    Version 7.3 28-Aug-07
80    ---------------------
81    
82     1. In the rejigging of the build system that eventually resulted in 7.1, the
83        line "#include <pcre.h>" was included in pcre_internal.h. The use of angle
84        brackets there is not right, since it causes compilers to look for an
85        installed pcre.h, not the version that is in the source that is being
86        compiled (which of course may be different). I have changed it back to:
87    
88          #include "pcre.h"
89    
90        I have a vague recollection that the change was concerned with compiling in
91        different directories, but in the new build system, that is taken care of
92        by the VPATH setting the Makefile.
93    
94     2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
95        when the subject happened to end in the byte 0x85 (e.g. if the last
96        character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
97        characters but of course it shouldn't be taken as a newline when it is part
98        of another character. The bug was that, for an unlimited repeat of . in
99        not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
100        characters when looking for a newline.
101    
102     3. A small performance improvement in the DOTALL UTF-8 mode .* case.
103    
104     4. Debugging: adjusted the names of opcodes for different kinds of parentheses
105        in debug output.
106    
107     5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
108        long printing in the pcrecpp unittest when running under MinGW.
109    
110     6. ESC_K was left out of the EBCDIC table.
111    
112     7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
113        parentheses; I made it 1000, which seemed large enough. Unfortunately, the
114        limit also applies to "virtual nesting" when a pattern is recursive, and in
115        this case 1000 isn't so big. I have been able to remove this limit at the
116        expense of backing off one optimization in certain circumstances. Normally,
117        when pcre_exec() would call its internal match() function recursively and
118        immediately return the result unconditionally, it uses a "tail recursion"
119        feature to save stack. However, when a subpattern that can match an empty
120        string has an unlimited repetition quantifier, it no longer makes this
121        optimization. That gives it a stack frame in which to save the data for
122        checking that an empty string has been matched. Previously this was taken
123        from the 1000-entry workspace that had been reserved. So now there is no
124        explicit limit, but more stack is used.
125    
126     8. Applied Daniel's patches to solve problems with the import/export magic
127        syntax that is required for Windows, and which was going wrong for the
128        pcreposix and pcrecpp parts of the library. These were overlooked when this
129        problem was solved for the main library.
130    
131     9. There were some crude static tests to avoid integer overflow when computing
132        the size of patterns that contain repeated groups with explicit upper
133        limits. As the maximum quantifier is 65535, the maximum group length was
134        set at 30,000 so that the product of these two numbers did not overflow a
135        32-bit integer. However, it turns out that people want to use groups that
136        are longer than 30,000 bytes (though not repeat them that many times).
137        Change 7.0/17 (the refactoring of the way the pattern size is computed) has
138        made it possible to implement the integer overflow checks in a much more
139        dynamic way, which I have now done. The artificial limitation on group
140        length has been removed - we now have only the limit on the total length of
141        the compiled pattern, which depends on the LINK_SIZE setting.
142    
143    10. Fixed a bug in the documentation for get/copy named substring when
144        duplicate names are permitted. If none of the named substrings are set, the
145        functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
146        empty string.
147    
148    11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E
149        instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error,
150        because the ] is interpreted as the first data character and the
151        terminating ] is not found. PCRE has been made compatible with Perl in this
152        regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could
153        cause memory overwriting.
154    
155    10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty
156        string has been matched (to stop an infinite loop). It was not recognizing
157        a conditional subpattern that could match an empty string if that
158        subpattern was within another subpattern. For example, it looped when
159        trying to match  (((?(1)X|))*)  but it was OK with  ((?(1)X|)*)  where the
160        condition was not nested. This bug has been fixed.
161    
162    12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
163        past the start of the subject in the presence of bytes with the top bit
164        set, for example "\x8aBCD".
165    
166    13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
167        (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
168    
169    14. Optimized (?!) to (*FAIL).
170    
171    15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
172        This restricts code points to be within the range 0 to 0x10FFFF, excluding
173        the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
174        full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
175        does: it's just the validity check that is more restrictive.
176    
177    16. Inserted checks for integer overflows during escape sequence (backslash)
178        processing, and also fixed erroneous offset values for syntax errors during
179        backslash processing.
180    
181    17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
182        for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
183    
184    18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
185        caused an overrun.
186    
187    19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
188        something other than just ASCII characters) inside a group that had an
189        unlimited repeat caused a loop at compile time (while checking to see
190        whether the group could match an empty string).
191    
192    20. Debugging a pattern containing \p or \P could cause a crash. For example,
193        [\P{Any}] did so. (Error in the code for printing property names.)
194    
195    21. An orphan \E inside a character class could cause a crash.
196    
197    22. A repeated capturing bracket such as (A)? could cause a wild memory
198        reference during compilation.
199    
200    23. There are several functions in pcre_compile() that scan along a compiled
201        expression for various reasons (e.g. to see if it's fixed length for look
202        behind). There were bugs in these functions when a repeated \p or \P was
203        present in the pattern. These operators have additional parameters compared
204        with \d, etc, and these were not being taken into account when moving along
205        the compiled data. Specifically:
206    
207        (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
208            length.
209    
210        (b) An item such as \pL+ within a repeated group could cause crashes or
211            loops.
212    
213        (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
214            "reference to non-existent subpattern" error.
215    
216        (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
217    
218    24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
219        characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
220    
221    25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
222    
223    26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
224        character were causing crashes (broken optimization).
225    
226    27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
227        \p or \P) caused a compile-time loop.
228    
229    28. More problems have arisen in unanchored patterns when CRLF is a valid line
230        break. For example, the unstudied pattern [\r\n]A does not match the string
231        "\r\nA" because change 7.0/46 below moves the current point on by two
232        characters after failing to match at the start. However, the pattern \nA
233        *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
234        the same is true. There doesn't seem any very clean way out of this, but
235        what I have chosen to do makes the common cases work: PCRE now takes note
236        of whether there can be an explicit match for \r or \n anywhere in the
237        pattern, and if so, 7.0/46 no longer applies. As part of this change,
238        there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
239        pattern has explicit CR or LF references.
240    
241    29. Added (*CR) etc for changing newline setting at start of pattern.
242    
243    
244    Version 7.2 19-Jun-07
245    ---------------------
246    
247     1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
248        which is apparently normally available under Windows.
249    
250     2. Re-jig the pcregrep tests with different newline settings in an attempt
251        to make them independent of the local environment's newline setting.
252    
253     3. Add code to configure.ac to remove -g from the CFLAGS default settings.
254    
255     4. Some of the "internals" tests were previously cut out when the link size
256        was not 2, because the output contained actual offsets. The recent new
257        "Z" feature of pcretest means that these can be cut out, making the tests
258        usable with all link sizes.
259    
260     5. Implemented Stan Switzer's goto replacement for longjmp() when not using
261        stack recursion. This gives a massive performance boost under BSD, but just
262        a small improvement under Linux. However, it saves one field in the frame
263        in all cases.
264    
265     6. Added more features from the forthcoming Perl 5.10:
266    
267        (a) (?-n) (where n is a string of digits) is a relative subroutine or
268            recursion call. It refers to the nth most recently opened parentheses.
269    
270        (b) (?+n) is also a relative subroutine call; it refers to the nth next
271            to be opened parentheses.
272    
273        (c) Conditions that refer to capturing parentheses can be specified
274            relatively, for example, (?(-2)... or (?(+3)...
275    
276        (d) \K resets the start of the current match so that everything before
277            is not part of it.
278    
279        (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible).
280    
281        (f) \g{name} is another synonym - part of Perl 5.10's unification of
282            reference syntax.
283    
284        (g) (?| introduces a group in which the numbering of parentheses in each
285            alternative starts with the same number.
286    
287        (h) \h, \H, \v, and \V match horizontal and vertical whitespace.
288    
289     7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and
290        PCRE_INFO_JCHANGED.
291    
292     8. A pattern such as  (.*(.)?)*  caused pcre_exec() to fail by either not
293        terminating or by crashing. Diagnosed by Viktor Griph; it was in the code
294        for detecting groups that can match an empty string.
295    
296     9. A pattern with a very large number of alternatives (more than several
297        hundred) was running out of internal workspace during the pre-compile
298        phase, where pcre_compile() figures out how much memory will be needed. A
299        bit of new cunning has reduced the workspace needed for groups with
300        alternatives. The 1000-alternative test pattern now uses 12 bytes of
301        workspace instead of running out of the 4096 that are available.
302    
303    10. Inserted some missing (unsigned int) casts to get rid of compiler warnings.
304    
305    11. Applied patch from Google to remove an optimization that didn't quite work.
306        The report of the bug said:
307    
308          pcrecpp::RE("a*").FullMatch("aaa") matches, while
309          pcrecpp::RE("a*?").FullMatch("aaa") does not, and
310          pcrecpp::RE("a*?\\z").FullMatch("aaa") does again.
311    
312    12. If \p or \P was used in non-UTF-8 mode on a character greater than 127
313        it matched the wrong number of bytes.
314    
315    
316    Version 7.1 24-Apr-07
317  ---------------------  ---------------------
318    
319   1. Applied Bob Rossi and Daniel G's patches to convert the build system to one   1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
320      that is more "standard", making use of automake and other autotools. There      that is more "standard", making use of automake and other Autotools. There
321      is some re-arrangement of the files and adjustment of comments consequent      is some re-arrangement of the files and adjustment of comments consequent
322      on this.      on this.
323    
# Line 26  Version 7.1 05-Mar-07 Line 338  Version 7.1 05-Mar-07
338      .br or .in.      .br or .in.
339    
340   4. Updated comments in configure.ac that get placed in config.h.in and also   4. Updated comments in configure.ac that get placed in config.h.in and also
341      arranged for config.h to be included in the distribution, with the name      arranged for config.h to be included in the distribution, with the name
342      config.h.generic, for the benefit of those who have to compile without      config.h.generic, for the benefit of those who have to compile without
343      Autotools (compare pcre.h, which is now distributed as pcre.h.generic).      Autotools (compare pcre.h, which is now distributed as pcre.h.generic).
344    
345   5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan   5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
346      Weber: (1) pcre_internal.h was missing some function renames; (2) updated      Weber: (1) pcre_internal.h was missing some function renames; (2) updated
347      makevp.bat for the current PCRE, using the additional files !compile.txt,      makevp.bat for the current PCRE, using the additional files
348      !linklib.txt, and pcregexp.pas.      makevp_c.txt, makevp_l.txt, and pcregexp.pas.
349    
350   6. A Windows user reported a minor discrepancy with test 2, which turned out   6. A Windows user reported a minor discrepancy with test 2, which turned out
351      to be caused by a trailing space on an input line that had got lost in his      to be caused by a trailing space on an input line that had got lost in his
# Line 63  Version 7.1 05-Mar-07 Line 375  Version 7.1 05-Mar-07
375  10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:  10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:
376    
377      (a) It was defining its arguments as char * instead of void *.      (a) It was defining its arguments as char * instead of void *.
378    
379      (b) It was assuming that all moves were upwards in memory; this was true      (b) It was assuming that all moves were upwards in memory; this was true
380          a long time ago when I wrote it, but is no longer the case.          a long time ago when I wrote it, but is no longer the case.
381    
382      The emulated memove() is provided for those environments that have neither      The emulated memove() is provided for those environments that have neither
383      memmove() nor bcopy(). I didn't think anyone used it these days, but that      memmove() nor bcopy(). I didn't think anyone used it these days, but that
384      is clearly not the case, as these two bugs were recently reported.      is clearly not the case, as these two bugs were recently reported.
385    
386  11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,  11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,
387      and Detrail to create the HTML documentation, the .txt form of the man      and Detrail to create the HTML documentation, the .txt form of the man
388      pages, and it removes trailing spaces from listed files. It also creates      pages, and it removes trailing spaces from listed files. It also creates
389      pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter      pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter
390      case, it wraps all the #defines with #ifndefs. This script should be run      case, it wraps all the #defines with #ifndefs. This script should be run
391      before "make dist".      before "make dist".
392    
393  12. Fixed two fairly obscure bugs concerned with quantified caseless matching  12. Fixed two fairly obscure bugs concerned with quantified caseless matching
394      with Unicode property support.      with Unicode property support.
395    
396      (a) For a maximizing quantifier, if the two different cases of the      (a) For a maximizing quantifier, if the two different cases of the
397          character were of different lengths in their UTF-8 codings (there are          character were of different lengths in their UTF-8 codings (there are
398          some cases like this - I found 11), and the matching function had to          some cases like this - I found 11), and the matching function had to
399          back up over a mixture of the two cases, it incorrectly assumed they          back up over a mixture of the two cases, it incorrectly assumed they
400          were both the same length.          were both the same length.
401    
402      (b) When PCRE was configured to use the heap rather than the stack for      (b) When PCRE was configured to use the heap rather than the stack for
403          recursion during matching, it was not correctly preserving the data for          recursion during matching, it was not correctly preserving the data for
404          the other case of a UTF-8 character when checking ahead for a match          the other case of a UTF-8 character when checking ahead for a match
405          while processing a minimizing repeat. If the check also involved          while processing a minimizing repeat. If the check also involved
406          matching a wide character, but failed, corruption could cause an          matching a wide character, but failed, corruption could cause an
407          erroneous result when trying to check for a repeat of the original          erroneous result when trying to check for a repeat of the original
408          character.          character.
409    
410  13. Some tidying changes to the testing mechanism:  13. Some tidying changes to the testing mechanism:
411    
412      (a) The RunTest script now detects the internal link size and whether there      (a) The RunTest script now detects the internal link size and whether there
413          is UTF-8 and UCP support by running ./pcretest -C instead of relying on          is UTF-8 and UCP support by running ./pcretest -C instead of relying on
414          values substituted by "configure". (The RunGrepTest script already did          values substituted by "configure". (The RunGrepTest script already did
415          this for UTF-8.) The configure.ac script no longer substitutes the          this for UTF-8.) The configure.ac script no longer substitutes the
416          relevant variables.          relevant variables.
417    
418      (b) The debugging options /B and /D in pcretest show the compiled bytecode      (b) The debugging options /B and /D in pcretest show the compiled bytecode
419          with length and offset values. This means that the output is different          with length and offset values. This means that the output is different
420          for different internal link sizes. Test 2 is skipped for link sizes          for different internal link sizes. Test 2 is skipped for link sizes
421          other than 2 because of this, bypassing the problem. Unfortunately,          other than 2 because of this, bypassing the problem. Unfortunately,
422          there was also a test in test 3 (the locale tests) that used /B and          there was also a test in test 3 (the locale tests) that used /B and
423          failed for link sizes other than 2. Rather than cut the whole test out,          failed for link sizes other than 2. Rather than cut the whole test out,
424          I have added a new /Z option to pcretest that replaces the length and          I have added a new /Z option to pcretest that replaces the length and
425          offset values with spaces. This is now used to make test 3 independent          offset values with spaces. This is now used to make test 3 independent
426          of link size.          of link size. (Test 2 will be tidied up later.)
427    
428    14. If erroroffset was passed as NULL to pcre_compile, it provoked a
429        segmentation fault instead of returning the appropriate error message.
430    
431    15. In multiline mode when the newline sequence was set to "any", the pattern
432        ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
433        This doesn't seem right; it now treats the CRLF combination as the line
434        ending, and so does not match in that case. It's only a pattern such as ^$
435        that would hit this one: something like ^ABC$ would have failed after \r
436        and then tried again after \r\n.
437    
438    16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
439        in an attempt to make files that differ only in their line terminators
440        compare equal. This works on Linux.
441    
442    17. Under certain error circumstances pcregrep might try to free random memory
443        as it exited. This is now fixed, thanks to valgrind.
444    
445    19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
446        "abc\r\n\r\n", it found an unwanted second match after the second \r. This
447        was because its rules for how to advance for /g after matching an empty
448        string at the end of a line did not allow for this case. They now check for
449        it specially.
450    
451    20. pcretest is supposed to handle patterns and data of any length, by
452        extending its buffers when necessary. It was getting this wrong when the
453        buffer for a data line had to be extended.
454    
455    21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
456        CRLF as a newline sequence.
457    
458    22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
459        out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
460        I have nevertheless tidied it up.
461    
462    23. Added some casts to kill warnings from HP-UX ia64 compiler.
463    
464    24. Added a man page for pcre-config.
465    
466    
467  Version 7.0 19-Dec-06  Version 7.0 19-Dec-06
468  ---------------------  ---------------------

Legend:
Removed from v.118  
changed lines
  Added in v.261

webmaster@exim.org
ViewVC Help
Powered by ViewVC 1.1.12