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Revision 991 - (show annotations)
Sun Jul 8 16:44:39 2012 UTC (7 years, 3 months ago) by zherczeg
File size: 233240 byte(s)
Error occurred while calculating annotation data.
Rename the leave variable names to quit to improve WinCE compatibility.
1 ChangeLog for PCRE
2 ------------------
3
4 Version 8.32
5 ------------
6
7 1. Improved JIT compiler optimizations for first character search and single
8 character iterators.
9
10 2. Supporting IBM XL C compilers for PPC architectures in the JIT compiler.
11 Patch by Daniel Richard G.
12
13 3. Single character iterator optimizations in the JIT compiler.
14
15 4. Improved JIT compiler optimizations for character ranges.
16
17 5. Rename the "leave" variable names to "quit" to improve WinCE compatibility.
18 Reported by Giuseppe D'Angelo.
19
20
21 Version 8.31 06-July-2012
22 -------------------------
23
24 1. Fixing a wrong JIT test case and some compiler warnings.
25
26 2. Removed a bashism from the RunTest script.
27
28 3. Add a cast to pcre_exec.c to fix the warning "unary minus operator applied
29 to unsigned type, result still unsigned" that was given by an MS compiler
30 on encountering the code "-sizeof(xxx)".
31
32 4. Partial matching support is added to the JIT compiler.
33
34 5. Fixed several bugs concerned with partial matching of items that consist
35 of more than one character:
36
37 (a) /^(..)\1/ did not partially match "aba" because checking references was
38 done on an "all or nothing" basis. This also applied to repeated
39 references.
40
41 (b) \R did not give a hard partial match if \r was found at the end of the
42 subject.
43
44 (c) \X did not give a hard partial match after matching one or more
45 characters at the end of the subject.
46
47 (d) When newline was set to CRLF, a pattern such as /a$/ did not recognize
48 a partial match for the string "\r".
49
50 (e) When newline was set to CRLF, the metacharacter "." did not recognize
51 a partial match for a CR character at the end of the subject string.
52
53 6. If JIT is requested using /S++ or -s++ (instead of just /S+ or -s+) when
54 running pcretest, the text "(JIT)" added to the output whenever JIT is
55 actually used to run the match.
56
57 7. Individual JIT compile options can be set in pcretest by following -s+[+]
58 or /S+[+] with a digit between 1 and 7.
59
60 8. OP_NOT now supports any UTF character not just single-byte ones.
61
62 9. (*MARK) control verb is now supported by the JIT compiler.
63
64 10. The command "./RunTest list" lists the available tests without actually
65 running any of them. (Because I keep forgetting what they all are.)
66
67 11. Add PCRE_INFO_MAXLOOKBEHIND.
68
69 12. Applied a (slightly modified) user-supplied patch that improves performance
70 when the heap is used for recursion (compiled with --disable-stack-for-
71 recursion). Instead of malloc and free for each heap frame each time a
72 logical recursion happens, frames are retained on a chain and re-used where
73 possible. This sometimes gives as much as 30% improvement.
74
75 13. As documented, (*COMMIT) is now confined to within a recursive subpattern
76 call.
77
78 14. As documented, (*COMMIT) is now confined to within a positive assertion.
79
80 15. It is now possible to link pcretest with libedit as an alternative to
81 libreadline.
82
83 16. (*COMMIT) control verb is now supported by the JIT compiler.
84
85 17. The Unicode data tables have been updated to Unicode 6.1.0.
86
87 18. Added --file-list option to pcregrep.
88
89 19. Added binary file support to pcregrep, including the -a, --binary-files,
90 -I, and --text options.
91
92 20. The madvise function is renamed for posix_madvise for QNX compatibility
93 reasons. Fixed by Giuseppe D'Angelo.
94
95 21. Fixed a bug for backward assertions with REVERSE 0 in the JIT compiler.
96
97 22. Changed the option for creating symbolic links for 16-bit man pages from
98 -s to -sf so that re-installing does not cause issues.
99
100 23. Support PCRE_NO_START_OPTIMIZE in JIT as (*MARK) support requires it.
101
102 24. Fixed a very old bug in pcretest that caused errors with restarted DFA
103 matches in certain environments (the workspace was not being correctly
104 retained). Also added to pcre_dfa_exec() a simple plausibility check on
105 some of the workspace data at the beginning of a restart.
106
107 25. \s*\R was auto-possessifying the \s* when it should not, whereas \S*\R
108 was not doing so when it should - probably a typo introduced by SVN 528
109 (change 8.10/14).
110
111 26. When PCRE_UCP was not set, \w+\x{c4} was incorrectly auto-possessifying the
112 \w+ when the character tables indicated that \x{c4} was a word character.
113 There were several related cases, all because the tests for doing a table
114 lookup were testing for characters less than 127 instead of 255.
115
116 27. If a pattern contains capturing parentheses that are not used in a match,
117 their slots in the ovector are set to -1. For those that are higher than
118 any matched groups, this happens at the end of processing. In the case when
119 there were back references that the ovector was too small to contain
120 (causing temporary malloc'd memory to be used during matching), and the
121 highest capturing number was not used, memory off the end of the ovector
122 was incorrectly being set to -1. (It was using the size of the temporary
123 memory instead of the true size.)
124
125 28. To catch bugs like 27 using valgrind, when pcretest is asked to specify an
126 ovector size, it uses memory at the end of the block that it has got.
127
128 29. Check for an overlong MARK name and give an error at compile time. The
129 limit is 255 for the 8-bit library and 65535 for the 16-bit library.
130
131 30. JIT compiler update.
132
133 31. JIT is now supported on jailbroken iOS devices. Thanks for Ruiger
134 Rill for the patch.
135
136 32. Put spaces around SLJIT_PRINT_D in the JIT compiler. Required by CXX11.
137
138 33. Variable renamings in the PCRE-JIT compiler. No functionality change.
139
140 34. Fixed typos in pcregrep: in two places there was SUPPORT_LIBZ2 instead of
141 SUPPORT_LIBBZ2. This caused a build problem when bzip2 but not gzip (zlib)
142 was enabled.
143
144 35. Improve JIT code generation for greedy plus quantifier.
145
146 36. When /((?:a?)*)*c/ or /((?>a?)*)*c/ was matched against "aac", it set group
147 1 to "aa" instead of to an empty string. The bug affected repeated groups
148 that could potentially match an empty string.
149
150 37. Optimizing single character iterators in JIT.
151
152 38. Wide characters specified with \uxxxx in JavaScript mode are now subject to
153 the same checks as \x{...} characters in non-JavaScript mode. Specifically,
154 codepoints that are too big for the mode are faulted, and in a UTF mode,
155 disallowed codepoints are also faulted.
156
157 39. If PCRE was compiled with UTF support, in three places in the DFA
158 matcher there was code that should only have been obeyed in UTF mode, but
159 was being obeyed unconditionally. In 8-bit mode this could cause incorrect
160 processing when bytes with values greater than 127 were present. In 16-bit
161 mode the bug would be provoked by values in the range 0xfc00 to 0xdc00. In
162 both cases the values are those that cannot be the first data item in a UTF
163 character. The three items that might have provoked this were recursions,
164 possessively repeated groups, and atomic groups.
165
166 40. Ensure that libpcre is explicitly listed in the link commands for pcretest
167 and pcregrep, because some OS require shared objects to be explicitly
168 passed to ld, causing the link step to fail if they are not.
169
170 41. There were two incorrect #ifdefs in pcre_study.c, meaning that, in 16-bit
171 mode, patterns that started with \h* or \R* might be incorrectly matched.
172
173
174 Version 8.30 04-February-2012
175 -----------------------------
176
177 1. Renamed "isnumber" as "is_a_number" because in some Mac environments this
178 name is defined in ctype.h.
179
180 2. Fixed a bug in fixed-length calculation for lookbehinds that would show up
181 only in quite long subpatterns.
182
183 3. Removed the function pcre_info(), which has been obsolete and deprecated
184 since it was replaced by pcre_fullinfo() in February 2000.
185
186 4. For a non-anchored pattern, if (*SKIP) was given with a name that did not
187 match a (*MARK), and the match failed at the start of the subject, a
188 reference to memory before the start of the subject could occur. This bug
189 was introduced by fix 17 of release 8.21.
190
191 5. A reference to an unset group with zero minimum repetition was giving
192 totally wrong answers (in non-JavaScript-compatibility mode). For example,
193 /(another)?(\1?)test/ matched against "hello world test". This bug was
194 introduced in release 8.13.
195
196 6. Add support for 16-bit character strings (a large amount of work involving
197 many changes and refactorings).
198
199 7. RunGrepTest failed on msys because \r\n was replaced by whitespace when the
200 command "pattern=`printf 'xxx\r\njkl'`" was run. The pattern is now taken
201 from a file.
202
203 8. Ovector size of 2 is also supported by JIT based pcre_exec (the ovector size
204 rounding is not applied in this particular case).
205
206 9. The invalid Unicode surrogate codepoints U+D800 to U+DFFF are now rejected
207 if they appear, or are escaped, in patterns.
208
209 10. Get rid of a number of -Wunused-but-set-variable warnings.
210
211 11. The pattern /(?=(*:x))(q|)/ matches an empty string, and returns the mark
212 "x". The similar pattern /(?=(*:x))((*:y)q|)/ did not return a mark at all.
213 Oddly, Perl behaves the same way. PCRE has been fixed so that this pattern
214 also returns the mark "x". This bug applied to capturing parentheses,
215 non-capturing parentheses, and atomic parentheses. It also applied to some
216 assertions.
217
218 12. Stephen Kelly's patch to CMakeLists.txt allows it to parse the version
219 information out of configure.ac instead of relying on pcre.h.generic, which
220 is not stored in the repository.
221
222 13. Applied Dmitry V. Levin's patch for a more portable method for linking with
223 -lreadline.
224
225 14. ZH added PCRE_CONFIG_JITTARGET; added its output to pcretest -C.
226
227 15. Applied Graycode's patch to put the top-level frame on the stack rather
228 than the heap when not using the stack for recursion. This gives a
229 performance improvement in many cases when recursion is not deep.
230
231 16. Experimental code added to "pcretest -C" to output the stack frame size.
232
233
234 Version 8.21 12-Dec-2011
235 ------------------------
236
237 1. Updating the JIT compiler.
238
239 2. JIT compiler now supports OP_NCREF, OP_RREF and OP_NRREF. New test cases
240 are added as well.
241
242 3. Fix cache-flush issue on PowerPC (It is still an experimental JIT port).
243 PCRE_EXTRA_TABLES is not suported by JIT, and should be checked before
244 calling _pcre_jit_exec. Some extra comments are added.
245
246 4. (*MARK) settings inside atomic groups that do not contain any capturing
247 parentheses, for example, (?>a(*:m)), were not being passed out. This bug
248 was introduced by change 18 for 8.20.
249
250 5. Supporting of \x, \U and \u in JavaScript compatibility mode based on the
251 ECMA-262 standard.
252
253 6. Lookbehinds such as (?<=a{2}b) that contained a fixed repetition were
254 erroneously being rejected as "not fixed length" if PCRE_CASELESS was set.
255 This bug was probably introduced by change 9 of 8.13.
256
257 7. While fixing 6 above, I noticed that a number of other items were being
258 incorrectly rejected as "not fixed length". This arose partly because newer
259 opcodes had not been added to the fixed-length checking code. I have (a)
260 corrected the bug and added tests for these items, and (b) arranged for an
261 error to occur if an unknown opcode is encountered while checking for fixed
262 length instead of just assuming "not fixed length". The items that were
263 rejected were: (*ACCEPT), (*COMMIT), (*FAIL), (*MARK), (*PRUNE), (*SKIP),
264 (*THEN), \h, \H, \v, \V, and single character negative classes with fixed
265 repetitions, e.g. [^a]{3}, with and without PCRE_CASELESS.
266
267 8. A possessively repeated conditional subpattern such as (?(?=c)c|d)++ was
268 being incorrectly compiled and would have given unpredicatble results.
269
270 9. A possessively repeated subpattern with minimum repeat count greater than
271 one behaved incorrectly. For example, (A){2,}+ behaved as if it was
272 (A)(A)++ which meant that, after a subsequent mismatch, backtracking into
273 the first (A) could occur when it should not.
274
275 10. Add a cast and remove a redundant test from the code.
276
277 11. JIT should use pcre_malloc/pcre_free for allocation.
278
279 12. Updated pcre-config so that it no longer shows -L/usr/lib, which seems
280 best practice nowadays, and helps with cross-compiling. (If the exec_prefix
281 is anything other than /usr, -L is still shown).
282
283 13. In non-UTF-8 mode, \C is now supported in lookbehinds and DFA matching.
284
285 14. Perl does not support \N without a following name in a [] class; PCRE now
286 also gives an error.
287
288 15. If a forward reference was repeated with an upper limit of around 2000,
289 it caused the error "internal error: overran compiling workspace". The
290 maximum number of forward references (including repeats) was limited by the
291 internal workspace, and dependent on the LINK_SIZE. The code has been
292 rewritten so that the workspace expands (via pcre_malloc) if necessary, and
293 the default depends on LINK_SIZE. There is a new upper limit (for safety)
294 of around 200,000 forward references. While doing this, I also speeded up
295 the filling in of repeated forward references.
296
297 16. A repeated forward reference in a pattern such as (a)(?2){2}(.) was
298 incorrectly expecting the subject to contain another "a" after the start.
299
300 17. When (*SKIP:name) is activated without a corresponding (*MARK:name) earlier
301 in the match, the SKIP should be ignored. This was not happening; instead
302 the SKIP was being treated as NOMATCH. For patterns such as
303 /A(*MARK:A)A+(*SKIP:B)Z|AAC/ this meant that the AAC branch was never
304 tested.
305
306 18. The behaviour of (*MARK), (*PRUNE), and (*THEN) has been reworked and is
307 now much more compatible with Perl, in particular in cases where the result
308 is a non-match for a non-anchored pattern. For example, if
309 /b(*:m)f|a(*:n)w/ is matched against "abc", the non-match returns the name
310 "m", where previously it did not return a name. A side effect of this
311 change is that for partial matches, the last encountered mark name is
312 returned, as for non matches. A number of tests that were previously not
313 Perl-compatible have been moved into the Perl-compatible test files. The
314 refactoring has had the pleasing side effect of removing one argument from
315 the match() function, thus reducing its stack requirements.
316
317 19. If the /S+ option was used in pcretest to study a pattern using JIT,
318 subsequent uses of /S (without +) incorrectly behaved like /S+.
319
320 21. Retrieve executable code size support for the JIT compiler and fixing
321 some warnings.
322
323 22. A caseless match of a UTF-8 character whose other case uses fewer bytes did
324 not work when the shorter character appeared right at the end of the
325 subject string.
326
327 23. Added some (int) casts to non-JIT modules to reduce warnings on 64-bit
328 systems.
329
330 24. Added PCRE_INFO_JITSIZE to pass on the value from (21) above, and also
331 output it when the /M option is used in pcretest.
332
333 25. The CheckMan script was not being included in the distribution. Also, added
334 an explicit "perl" to run Perl scripts from the PrepareRelease script
335 because this is reportedly needed in Windows.
336
337 26. If study data was being save in a file and studying had not found a set of
338 "starts with" bytes for the pattern, the data written to the file (though
339 never used) was taken from uninitialized memory and so caused valgrind to
340 complain.
341
342 27. Updated RunTest.bat as provided by Sheri Pierce.
343
344 28. Fixed a possible uninitialized memory bug in pcre_jit_compile.c.
345
346 29. Computation of memory usage for the table of capturing group names was
347 giving an unnecessarily large value.
348
349
350 Version 8.20 21-Oct-2011
351 ------------------------
352
353 1. Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
354 a POSIX class. After further experiments with Perl, which convinced me that
355 Perl has bugs and confusions, a closing square bracket is no longer allowed
356 in a POSIX name. This bug also affected patterns with classes that started
357 with full stops.
358
359 2. If a pattern such as /(a)b|ac/ is matched against "ac", there is no
360 captured substring, but while checking the failing first alternative,
361 substring 1 is temporarily captured. If the output vector supplied to
362 pcre_exec() was not big enough for this capture, the yield of the function
363 was still zero ("insufficient space for captured substrings"). This cannot
364 be totally fixed without adding another stack variable, which seems a lot
365 of expense for a edge case. However, I have improved the situation in cases
366 such as /(a)(b)x|abc/ matched against "abc", where the return code
367 indicates that fewer than the maximum number of slots in the ovector have
368 been set.
369
370 3. Related to (2) above: when there are more back references in a pattern than
371 slots in the output vector, pcre_exec() uses temporary memory during
372 matching, and copies in the captures as far as possible afterwards. It was
373 using the entire output vector, but this conflicts with the specification
374 that only 2/3 is used for passing back captured substrings. Now it uses
375 only the first 2/3, for compatibility. This is, of course, another edge
376 case.
377
378 4. Zoltan Herczeg's just-in-time compiler support has been integrated into the
379 main code base, and can be used by building with --enable-jit. When this is
380 done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
381 runtime --no-jit option is given.
382
383 5. When the number of matches in a pcre_dfa_exec() run exactly filled the
384 ovector, the return from the function was zero, implying that there were
385 other matches that did not fit. The correct "exactly full" value is now
386 returned.
387
388 6. If a subpattern that was called recursively or as a subroutine contained
389 (*PRUNE) or any other control that caused it to give a non-standard return,
390 invalid errors such as "Error -26 (nested recursion at the same subject
391 position)" or even infinite loops could occur.
392
393 7. If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
394 computing the minimum length on reaching *ACCEPT, and so ended up with the
395 wrong value of 1 rather than 0. Further investigation indicates that
396 computing a minimum subject length in the presence of *ACCEPT is difficult
397 (think back references, subroutine calls), and so I have changed the code
398 so that no minimum is registered for a pattern that contains *ACCEPT.
399
400 8. If (*THEN) was present in the first (true) branch of a conditional group,
401 it was not handled as intended. [But see 16 below.]
402
403 9. Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
404 Sheri Pierce.
405
406 10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
407 the first byte in a match must be "a".
408
409 11. Change 17 for 8.13 increased the recursion depth for patterns like
410 /a(?:.)*?a/ drastically. I've improved things by remembering whether a
411 pattern contains any instances of (*THEN). If it does not, the old
412 optimizations are restored. It would be nice to do this on a per-group
413 basis, but at the moment that is not feasible.
414
415 12. In some environments, the output of pcretest -C is CRLF terminated. This
416 broke RunTest's code that checks for the link size. A single white space
417 character after the value is now allowed for.
418
419 13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
420 For "fr", it uses the Windows-specific input and output files.
421
422 14. If (*THEN) appeared in a group that was called recursively or as a
423 subroutine, it did not work as intended. [But see next item.]
424
425 15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
426 pattern fragments (but not containing any | characters). If A and B are
427 matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
428 was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
429 D. In other words, Perl considers parentheses that do not contain any |
430 characters to be part of a surrounding alternative, whereas PCRE was
431 treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
432 differently. PCRE now behaves in the same way as Perl, except in the case
433 of subroutine/recursion calls such as (?1) which have in any case always
434 been different (but PCRE had them first :-).
435
436 16. Related to 15 above: Perl does not treat the | in a conditional group as
437 creating alternatives. Such a group is treated in the same way as an
438 ordinary group without any | characters when processing (*THEN). PCRE has
439 been changed to match Perl's behaviour.
440
441 17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
442 RunGrepTest script failed.
443
444 18. Change 22 for version 13 caused atomic groups to use more stack. This is
445 inevitable for groups that contain captures, but it can lead to a lot of
446 stack use in large patterns. The old behaviour has been restored for atomic
447 groups that do not contain any capturing parentheses.
448
449 19. If the PCRE_NO_START_OPTIMIZE option was set for pcre_compile(), it did not
450 suppress the check for a minimum subject length at run time. (If it was
451 given to pcre_exec() or pcre_dfa_exec() it did work.)
452
453 20. Fixed an ASCII-dependent infelicity in pcretest that would have made it
454 fail to work when decoding hex characters in data strings in EBCDIC
455 environments.
456
457 21. It appears that in at least one Mac OS environment, the isxdigit() function
458 is implemented as a macro that evaluates to its argument more than once,
459 contravening the C 90 Standard (I haven't checked a later standard). There
460 was an instance in pcretest which caused it to go wrong when processing
461 \x{...} escapes in subject strings. The has been rewritten to avoid using
462 things like p++ in the argument of isxdigit().
463
464
465 Version 8.13 16-Aug-2011
466 ------------------------
467
468 1. The Unicode data tables have been updated to Unicode 6.0.0.
469
470 2. Two minor typos in pcre_internal.h have been fixed.
471
472 3. Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
473 pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
474 in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
475
476 4. There were a number of related bugs in the code for matching backrefences
477 caselessly in UTF-8 mode when codes for the characters concerned were
478 different numbers of bytes. For example, U+023A and U+2C65 are an upper
479 and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
480 (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
481 code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
482 2-byte code at the end of the subject (it thought there wasn't enough data
483 left).
484
485 5. Comprehensive information about what went wrong is now returned by
486 pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
487 as the output vector has at least 2 elements. The offset of the start of
488 the failing character and a reason code are placed in the vector.
489
490 6. When the UTF-8 string check fails for pcre_compile(), the offset that is
491 now returned is for the first byte of the failing character, instead of the
492 last byte inspected. This is an incompatible change, but I hope it is small
493 enough not to be a problem. It makes the returned offset consistent with
494 pcre_exec() and pcre_dfa_exec().
495
496 7. pcretest now gives a text phrase as well as the error number when
497 pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
498 failure, the offset and reason code are output.
499
500 8. When \R was used with a maximizing quantifier it failed to skip backwards
501 over a \r\n pair if the subsequent match failed. Instead, it just skipped
502 back over a single character (\n). This seems wrong (because it treated the
503 two characters as a single entity when going forwards), conflicts with the
504 documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
505 behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
506 has been changed.
507
508 9. Some internal refactoring has changed the processing so that the handling
509 of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
510 time (the PCRE_DOTALL option was changed this way some time ago: version
511 7.7 change 16). This has made it possible to abolish the OP_OPT op code,
512 which was always a bit of a fudge. It also means that there is one less
513 argument for the match() function, which reduces its stack requirements
514 slightly. This change also fixes an incompatibility with Perl: the pattern
515 (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
516
517 10. More internal refactoring has drastically reduced the number of recursive
518 calls to match() for possessively repeated groups such as (abc)++ when
519 using pcre_exec().
520
521 11. While implementing 10, a number of bugs in the handling of groups were
522 discovered and fixed:
523
524 (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
525 (a|)*(?1) gave a compile-time internal error.
526 ((a|)+)+ did not notice that the outer group could match an empty string.
527 (^a|^)+ was not marked as anchored.
528 (.*a|.*)+ was not marked as matching at start or after a newline.
529
530 12. Yet more internal refactoring has removed another argument from the match()
531 function. Special calls to this function are now indicated by setting a
532 value in a variable in the "match data" data block.
533
534 13. Be more explicit in pcre_study() instead of relying on "default" for
535 opcodes that mean there is no starting character; this means that when new
536 ones are added and accidentally left out of pcre_study(), testing should
537 pick them up.
538
539 14. The -s option of pcretest has been documented for ages as being an old
540 synonym of -m (show memory usage). I have changed it to mean "force study
541 for every regex", that is, assume /S for every regex. This is similar to -i
542 and -d etc. It's slightly incompatible, but I'm hoping nobody is still
543 using it. It makes it easier to run collections of tests with and without
544 study enabled, and thereby test pcre_study() more easily. All the standard
545 tests are now run with and without -s (but some patterns can be marked as
546 "never study" - see 20 below).
547
548 15. When (*ACCEPT) was used in a subpattern that was called recursively, the
549 restoration of the capturing data to the outer values was not happening
550 correctly.
551
552 16. If a recursively called subpattern ended with (*ACCEPT) and matched an
553 empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
554 pattern had matched an empty string, and so incorrectly returned a no
555 match.
556
557 17. There was optimizing code for the last branch of non-capturing parentheses,
558 and also for the obeyed branch of a conditional subexpression, which used
559 tail recursion to cut down on stack usage. Unfortunately, now that there is
560 the possibility of (*THEN) occurring in these branches, tail recursion is
561 no longer possible because the return has to be checked for (*THEN). These
562 two optimizations have therefore been removed. [But see 8.20/11 above.]
563
564 18. If a pattern containing \R was studied, it was assumed that \R always
565 matched two bytes, thus causing the minimum subject length to be
566 incorrectly computed because \R can also match just one byte.
567
568 19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
569 was incorrectly computed.
570
571 20. If /S is present twice on a test pattern in pcretest input, it now
572 *disables* studying, thereby overriding the use of -s on the command line
573 (see 14 above). This is necessary for one or two tests to keep the output
574 identical in both cases.
575
576 21. When (*ACCEPT) was used in an assertion that matched an empty string and
577 PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
578
579 22. When an atomic group that contained a capturing parenthesis was
580 successfully matched, but the branch in which it appeared failed, the
581 capturing was not being forgotten if a higher numbered group was later
582 captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
583 group 1 to "a", when in fact it should be unset. This applied to multi-
584 branched capturing and non-capturing groups, repeated or not, and also to
585 positive assertions (capturing in negative assertions does not happen
586 in PCRE) and also to nested atomic groups.
587
588 23. Add the ++ qualifier feature to pcretest, to show the remainder of the
589 subject after a captured substring, to make it easier to tell which of a
590 number of identical substrings has been captured.
591
592 24. The way atomic groups are processed by pcre_exec() has been changed so that
593 if they are repeated, backtracking one repetition now resets captured
594 values correctly. For example, if ((?>(a+)b)+aabab) is matched against
595 "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
596 "aaa". Previously, it would have been "a". As part of this code
597 refactoring, the way recursive calls are handled has also been changed.
598
599 25. If an assertion condition captured any substrings, they were not passed
600 back unless some other capturing happened later. For example, if
601 (?(?=(a))a) was matched against "a", no capturing was returned.
602
603 26. When studying a pattern that contained subroutine calls or assertions,
604 the code for finding the minimum length of a possible match was handling
605 direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
606 group 1 called group 2 while simultaneously a separate group 2 called group
607 1). A stack overflow occurred in this case. I have fixed this by limiting
608 the recursion depth to 10.
609
610 27. Updated RunTest.bat in the distribution to the version supplied by Tom
611 Fortmann. This supports explicit test numbers on the command line, and has
612 argument validation and error reporting.
613
614 28. An instance of \X with an unlimited repeat could fail if at any point the
615 first character it looked at was a mark character.
616
617 29. Some minor code refactoring concerning Unicode properties and scripts
618 should reduce the stack requirement of match() slightly.
619
620 30. Added the '=' option to pcretest to check the setting of unused capturing
621 slots at the end of the pattern, which are documented as being -1, but are
622 not included in the return count.
623
624 31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
625 compiled something random. Now it gives a compile-time error (as does
626 Perl).
627
628 32. A *MARK encountered during the processing of a positive assertion is now
629 recorded and passed back (compatible with Perl).
630
631 33. If --only-matching or --colour was set on a pcregrep call whose pattern
632 had alternative anchored branches, the search for a second match in a line
633 was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
634 matched the line "0102" twice. The same bug affected patterns that started
635 with a backwards assertion. For example /\b01|\b02/ also matched "0102"
636 twice.
637
638 34. Previously, PCRE did not allow quantification of assertions. However, Perl
639 does, and because of capturing effects, quantifying parenthesized
640 assertions may at times be useful. Quantifiers are now allowed for
641 parenthesized assertions.
642
643 35. A minor code tidy in pcre_compile() when checking options for \R usage.
644
645 36. \g was being checked for fancy things in a character class, when it should
646 just be a literal "g".
647
648 37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
649 appearance of a nested POSIX class supersedes an apparent external class.
650 For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
651 unescaped square brackets may also appear as part of class names. For
652 example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
653 more like Perl. (But see 8.20/1 above.)
654
655 38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
656 was because it thought it was \N{name}, which is not supported).
657
658 39. Add minix to OS list not supporting the -S option in pcretest.
659
660 40. PCRE tries to detect cases of infinite recursion at compile time, but it
661 cannot analyze patterns in sufficient detail to catch mutual recursions
662 such as ((?1))((?2)). There is now a runtime test that gives an error if a
663 subgroup is called recursively as a subpattern for a second time at the
664 same position in the subject string. In previous releases this might have
665 been caught by the recursion limit, or it might have run out of stack.
666
667 41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
668 happen only once. PCRE was, however incorrectly giving a compile time error
669 "recursive call could loop indefinitely" because it cannot analyze the
670 pattern in sufficient detail. The compile time test no longer happens when
671 PCRE is compiling a conditional subpattern, but actual runaway loops are
672 now caught at runtime (see 40 above).
673
674 42. It seems that Perl allows any characters other than a closing parenthesis
675 to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
676 has been changed to be the same.
677
678 43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
679 as not to get warnings when autogen.sh is called. Also changed
680 AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
681
682 44. To help people who use pcregrep to scan files containing exceedingly long
683 lines, the following changes have been made:
684
685 (a) The default value of the buffer size parameter has been increased from
686 8K to 20K. (The actual buffer used is three times this size.)
687
688 (b) The default can be changed by ./configure --with-pcregrep-bufsize when
689 PCRE is built.
690
691 (c) A --buffer-size=n option has been added to pcregrep, to allow the size
692 to be set at run time.
693
694 (d) Numerical values in pcregrep options can be followed by K or M, for
695 example --buffer-size=50K.
696
697 (e) If a line being scanned overflows pcregrep's buffer, an error is now
698 given and the return code is set to 2.
699
700 45. Add a pointer to the latest mark to the callout data block.
701
702 46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
703 partial match of an empty string instead of no match. This was specific to
704 the use of ".".
705
706 47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
707 complete match instead of a partial match. This bug was dependent on both
708 the PCRE_UTF8 and PCRE_DOTALL options being set.
709
710 48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
711 starting byte set, because \b was not being ignored.
712
713
714 Version 8.12 15-Jan-2011
715 ------------------------
716
717 1. Fixed some typos in the markup of the man pages, and wrote a script that
718 checks for such things as part of the documentation building process.
719
720 2. On a big-endian 64-bit system, pcregrep did not correctly process the
721 --match-limit and --recursion-limit options (added for 8.11). In
722 particular, this made one of the standard tests fail. (The integer value
723 went into the wrong half of a long int.)
724
725 3. If the --colour option was given to pcregrep with -v (invert match), it
726 did strange things, either producing crazy output, or crashing. It should,
727 of course, ignore a request for colour when reporting lines that do not
728 match.
729
730 4. Another pcregrep bug caused similar problems if --colour was specified with
731 -M (multiline) and the pattern match finished with a line ending.
732
733 5. In pcregrep, when a pattern that ended with a literal newline sequence was
734 matched in multiline mode, the following line was shown as part of the
735 match. This seems wrong, so I have changed it.
736
737 6. Another pcregrep bug in multiline mode, when --colour was specified, caused
738 the check for further matches in the same line (so they could be coloured)
739 to overrun the end of the current line. If another match was found, it was
740 incorrectly shown (and then shown again when found in the next line).
741
742 7. If pcregrep was compiled under Windows, there was a reference to the
743 function pcregrep_exit() before it was defined. I am assuming this was
744 the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
745 reported by a user. I've moved the definition above the reference.
746
747
748 Version 8.11 10-Dec-2010
749 ------------------------
750
751 1. (*THEN) was not working properly if there were untried alternatives prior
752 to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
753 backtracked to try for "b" instead of moving to the next alternative branch
754 at the same level (in this case, to look for "c"). The Perl documentation
755 is clear that when (*THEN) is backtracked onto, it goes to the "next
756 alternative in the innermost enclosing group".
757
758 2. (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
759 such as (A(*COMMIT)B(*THEN)C|D) any failure after matching A should
760 result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
761 (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
762 (*THEN).
763
764 3. If \s appeared in a character class, it removed the VT character from
765 the class, even if it had been included by some previous item, for example
766 in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
767 of \s, but is part of the POSIX "space" class.)
768
769 4. A partial match never returns an empty string (because you can always
770 match an empty string at the end of the subject); however the checking for
771 an empty string was starting at the "start of match" point. This has been
772 changed to the "earliest inspected character" point, because the returned
773 data for a partial match starts at this character. This means that, for
774 example, /(?<=abc)def/ gives a partial match for the subject "abc"
775 (previously it gave "no match").
776
777 5. Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
778 of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
779 previously a full match would be given. However, setting PCRE_PARTIAL_HARD
780 has an implication that the given string is incomplete (because a partial
781 match is preferred over a full match). For this reason, these items now
782 give a partial match in this situation. [Aside: previously, the one case
783 /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
784 match rather than a full match, which was wrong by the old rules, but is
785 now correct.]
786
787 6. There was a bug in the handling of #-introduced comments, recognized when
788 PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
789 If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
790 UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
791 scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
792 but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
793 places in pcre_compile().
794
795 7. Related to (6) above, when pcre_compile() was skipping #-introduced
796 comments when looking ahead for named forward references to subpatterns,
797 the only newline sequence it recognized was NL. It now handles newlines
798 according to the set newline convention.
799
800 8. SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
801 former, but used strtoul(), whereas pcretest avoided strtoul() but did not
802 cater for a lack of strerror(). These oversights have been fixed.
803
804 9. Added --match-limit and --recursion-limit to pcregrep.
805
806 10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
807
808 11. When the -o option was used, pcregrep was setting a return code of 1, even
809 when matches were found, and --line-buffered was not being honoured.
810
811 12. Added an optional parentheses number to the -o and --only-matching options
812 of pcregrep.
813
814 13. Imitating Perl's /g action for multiple matches is tricky when the pattern
815 can match an empty string. The code to do it in pcretest and pcredemo
816 needed fixing:
817
818 (a) When the newline convention was "crlf", pcretest got it wrong, skipping
819 only one byte after an empty string match just before CRLF (this case
820 just got forgotten; "any" and "anycrlf" were OK).
821
822 (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
823 mode when an empty string match preceded an ASCII character followed by
824 a non-ASCII character. (The code for advancing by one character rather
825 than one byte was nonsense.)
826
827 (c) The pcredemo.c sample program did not have any code at all to handle
828 the cases when CRLF is a valid newline sequence.
829
830 14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
831 as a starting offset was within the subject string. There is now a new
832 error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
833 negative or greater than the length of the string. In order to test this,
834 pcretest is extended to allow the setting of negative starting offsets.
835
836 15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
837 starting offset points to the beginning of a UTF-8 character was
838 unnecessarily clumsy. I tidied it up.
839
840 16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
841 bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
842
843 17. Nobody had reported that the --include_dir option, which was added in
844 release 7.7 should have been called --include-dir (hyphen, not underscore)
845 for compatibility with GNU grep. I have changed it to --include-dir, but
846 left --include_dir as an undocumented synonym, and the same for
847 --exclude-dir, though that is not available in GNU grep, at least as of
848 release 2.5.4.
849
850 18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
851 characters from a string of bytes) have been redefined so as not to use
852 loops, in order to improve performance in some environments. At the same
853 time, I abstracted some of the common code into auxiliary macros to save
854 repetition (this should not affect the compiled code).
855
856 19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
857 compile-time error is now given if \c is not followed by an ASCII
858 character, that is, a byte less than 128. (In EBCDIC mode, the code is
859 different, and any byte value is allowed.)
860
861 20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
862 START_OPTIMIZE option, which is now allowed at compile time - but just
863 passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
864 to pcregrep and other applications that have no direct access to PCRE
865 options. The new /Y option in pcretest sets this option when calling
866 pcre_compile().
867
868 21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
869 back references. Groups containing recursive back references were forced to
870 be atomic by that change, but in the case of named groups, the amount of
871 memory required was incorrectly computed, leading to "Failed: internal
872 error: code overflow". This has been fixed.
873
874 22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
875 pcretest.c, to avoid build problems in some Borland environments.
876
877
878 Version 8.10 25-Jun-2010
879 ------------------------
880
881 1. Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
882 THEN.
883
884 2. (*ACCEPT) was not working when inside an atomic group.
885
886 3. Inside a character class, \B is treated as a literal by default, but
887 faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
888 causes the error). The code is unchanged, but I tidied the documentation.
889
890 4. Inside a character class, PCRE always treated \R and \X as literals,
891 whereas Perl faults them if its -w option is set. I have changed PCRE so
892 that it faults them when PCRE_EXTRA is set.
893
894 5. Added support for \N, which always matches any character other than
895 newline. (It is the same as "." when PCRE_DOTALL is not set.)
896
897 6. When compiling pcregrep with newer versions of gcc which may have
898 FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
899 declared with attribute warn_unused_result" were given. Just casting the
900 result to (void) does not stop the warnings; a more elaborate fudge is
901 needed. I've used a macro to implement this.
902
903 7. Minor change to pcretest.c to avoid a compiler warning.
904
905 8. Added four artifical Unicode properties to help with an option to make
906 \s etc use properties (see next item). The new properties are: Xan
907 (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
908
909 9. Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
910 use Unicode properties. (*UCP) at the start of a pattern can be used to set
911 this option. Modified pcretest to add /W to test this facility. Added
912 REG_UCP to make it available via the POSIX interface.
913
914 10. Added --line-buffered to pcregrep.
915
916 11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
917 studied, and the match started with a letter with a code point greater than
918 127 whose first byte was different to the first byte of the other case of
919 the letter, the other case of this starting letter was not recognized
920 (#976).
921
922 12. If a pattern that was studied started with a repeated Unicode property
923 test, for example, \p{Nd}+, there was the theoretical possibility of
924 setting up an incorrect bitmap of starting bytes, but fortunately it could
925 not have actually happened in practice until change 8 above was made (it
926 added property types that matched character-matching opcodes).
927
928 13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
929 possible starting bytes for non-anchored patterns.
930
931 14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
932 \R, and also a number of cases that involve Unicode properties, both
933 explicit and implicit when PCRE_UCP is set.
934
935 15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
936 input, it could crash or give wrong results if characters with values
937 greater than 0xc0 were present in the subject string. (Detail: it assumed
938 UTF-8 input when processing these items.)
939
940 16. Added a lot of (int) casts to avoid compiler warnings in systems where
941 size_t is 64-bit (#991).
942
943 17. Added a check for running out of memory when PCRE is compiled with
944 --disable-stack-for-recursion (#990).
945
946 18. If the last data line in a file for pcretest does not have a newline on
947 the end, a newline was missing in the output.
948
949 19. The default pcre_chartables.c file recognizes only ASCII characters (values
950 less than 128) in its various bitmaps. However, there is a facility for
951 generating tables according to the current locale when PCRE is compiled. It
952 turns out that in some environments, 0x85 and 0xa0, which are Unicode space
953 characters, are recognized by isspace() and therefore were getting set in
954 these tables, and indeed these tables seem to approximate to ISO 8859. This
955 caused a problem in UTF-8 mode when pcre_study() was used to create a list
956 of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
957 which of course cannot start UTF-8 characters. I have changed the code so
958 that only real ASCII characters (less than 128) and the correct starting
959 bytes for UTF-8 encodings are set for characters greater than 127 when in
960 UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
961 altogether.)
962
963 20. Added the /T option to pcretest so as to be able to run tests with non-
964 standard character tables, thus making it possible to include the tests
965 used for 19 above in the standard set of tests.
966
967 21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
968 reference to a subpattern the other side of a comment that contains an
969 opening parenthesis caused either an internal compiling error, or a
970 reference to the wrong subpattern.
971
972
973 Version 8.02 19-Mar-2010
974 ------------------------
975
976 1. The Unicode data tables have been updated to Unicode 5.2.0.
977
978 2. Added the option --libs-cpp to pcre-config, but only when C++ support is
979 configured.
980
981 3. Updated the licensing terms in the pcregexp.pas file, as agreed with the
982 original author of that file, following a query about its status.
983
984 4. On systems that do not have stdint.h (e.g. Solaris), check for and include
985 inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
986
987 5. A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
988 quantifier applied to a forward-referencing subroutine call, could compile
989 incorrect code or give the error "internal error: previously-checked
990 referenced subpattern not found".
991
992 6. Both MS Visual Studio and Symbian OS have problems with initializing
993 variables to point to external functions. For these systems, therefore,
994 pcre_malloc etc. are now initialized to local functions that call the
995 relevant global functions.
996
997 7. There were two entries missing in the vectors called coptable and poptable
998 in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
999 I've fixed the data, and added a kludgy way of testing at compile time that
1000 the lengths are correct (equal to the number of opcodes).
1001
1002 8. Following on from 7, I added a similar kludge to check the length of the
1003 eint vector in pcreposix.c.
1004
1005 9. Error texts for pcre_compile() are held as one long string to avoid too
1006 much relocation at load time. To find a text, the string is searched,
1007 counting zeros. There was no check for running off the end of the string,
1008 which could happen if a new error number was added without updating the
1009 string.
1010
1011 10. \K gave a compile-time error if it appeared in a lookbehind assersion.
1012
1013 11. \K was not working if it appeared in an atomic group or in a group that
1014 was called as a "subroutine", or in an assertion. Perl 5.11 documents that
1015 \K is "not well defined" if used in an assertion. PCRE now accepts it if
1016 the assertion is positive, but not if it is negative.
1017
1018 12. Change 11 fortuitously reduced the size of the stack frame used in the
1019 "match()" function of pcre_exec.c by one pointer. Forthcoming
1020 implementation of support for (*MARK) will need an extra pointer on the
1021 stack; I have reserved it now, so that the stack frame size does not
1022 decrease.
1023
1024 13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
1025 item in branch that calls a recursion is a subroutine call - as in the
1026 second branch in the above example - was incorrectly given the compile-
1027 time error "recursive call could loop indefinitely" because pcre_compile()
1028 was not correctly checking the subroutine for matching a non-empty string.
1029
1030 14. The checks for overrunning compiling workspace could trigger after an
1031 overrun had occurred. This is a "should never occur" error, but it can be
1032 triggered by pathological patterns such as hundreds of nested parentheses.
1033 The checks now trigger 100 bytes before the end of the workspace.
1034
1035 15. Fix typo in configure.ac: "srtoq" should be "strtoq".
1036
1037
1038 Version 8.01 19-Jan-2010
1039 ------------------------
1040
1041 1. If a pattern contained a conditional subpattern with only one branch (in
1042 particular, this includes all (*DEFINE) patterns), a call to pcre_study()
1043 computed the wrong minimum data length (which is of course zero for such
1044 subpatterns). This could cause incorrect "no match" results.
1045
1046 2. For patterns such as (?i)a(?-i)b|c where an option setting at the start of
1047 the pattern is reset in the first branch, pcre_compile() failed with
1048 "internal error: code overflow at offset...". This happened only when
1049 the reset was to the original external option setting. (An optimization
1050 abstracts leading options settings into an external setting, which was the
1051 cause of this.)
1052
1053 3. A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
1054 of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
1055 assertion pattern did not match (meaning that the assertion was true), it
1056 was incorrectly treated as false if the SKIP had been reached during the
1057 matching. This also applied to assertions used as conditions.
1058
1059 4. If an item that is not supported by pcre_dfa_exec() was encountered in an
1060 assertion subpattern, including such a pattern used as a condition,
1061 unpredictable results occurred, instead of the error return
1062 PCRE_ERROR_DFA_UITEM.
1063
1064 5. The C++ GlobalReplace function was not working like Perl for the special
1065 situation when an empty string is matched. It now does the fancy magic
1066 stuff that is necessary.
1067
1068 6. In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
1069 removed. (These were left over from very, very early versions of PCRE.)
1070
1071 7. Some cosmetic changes to the code to make life easier when compiling it
1072 as part of something else:
1073
1074 (a) Change DEBUG to PCRE_DEBUG.
1075
1076 (b) In pcre_compile(), rename the member of the "branch_chain" structure
1077 called "current" as "current_branch", to prevent a collision with the
1078 Linux macro when compiled as a kernel module.
1079
1080 (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
1081 prevent a collision with the Linux macro when compiled as a kernel
1082 module.
1083
1084 8. In pcre_compile() there are some checks for integer overflows that used to
1085 cast potentially large values to (double). This has been changed to that
1086 when building, a check for int64_t is made, and if it is found, it is used
1087 instead, thus avoiding the use of floating point arithmetic. (There is no
1088 other use of FP in PCRE.) If int64_t is not found, the fallback is to
1089 double.
1090
1091 9. Added two casts to avoid signed/unsigned warnings from VS Studio Express
1092 2005 (difference between two addresses compared to an unsigned value).
1093
1094 10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
1095 custom one, because of the following reported problem in Windows:
1096
1097 - libbz2 uses the Pascal calling convention (WINAPI) for the functions
1098 under Win32.
1099 - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
1100 therefore missing the function definition.
1101 - The compiler thus generates a "C" signature for the test function.
1102 - The linker fails to find the "C" function.
1103 - PCRE fails to configure if asked to do so against libbz2.
1104
1105 11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
1106 messages were output:
1107
1108 Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
1109 rerunning libtoolize, to keep the correct libtool macros in-tree.
1110 Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
1111
1112 I have done both of these things.
1113
1114 12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
1115 most of the time, it *can* run out if it is given a pattern that contains a
1116 runaway infinite recursion. I updated the discussion in the pcrestack man
1117 page.
1118
1119 13. Now that we have gone to the x.xx style of version numbers, the minor
1120 version may start with zero. Using 08 or 09 is a bad idea because users
1121 might check the value of PCRE_MINOR in their code, and 08 or 09 may be
1122 interpreted as invalid octal numbers. I've updated the previous comment in
1123 configure.ac, and also added a check that gives an error if 08 or 09 are
1124 used.
1125
1126 14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
1127 causing partial matching to fail when the end of the subject matched \W
1128 in a UTF-8 pattern where \W was quantified with a minimum of 3.
1129
1130 15. There were some discrepancies between the declarations in pcre_internal.h
1131 of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
1132 their definitions. The declarations used "const uschar *" and the
1133 definitions used USPTR. Even though USPTR is normally defined as "const
1134 unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
1135 reported that: "This difference in casting confuses some C++ compilers, for
1136 example, SunCC recognizes above declarations as different functions and
1137 generates broken code for hbpcre." I have changed the declarations to use
1138 USPTR.
1139
1140 16. GNU libtool is named differently on some systems. The autogen.sh script now
1141 tries several variants such as glibtoolize (MacOSX) and libtoolize1x
1142 (FreeBSD).
1143
1144 17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
1145 (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
1146 comment: "Figure out how to create a longlong from a string: strtoll and
1147 equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
1148 instance, but it only takes 2 args instead of 3!"
1149
1150 18. A subtle bug concerned with back references has been fixed by a change of
1151 specification, with a corresponding code fix. A pattern such as
1152 ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
1153 refers, was giving matches when it shouldn't. For example, xa=xaaa would
1154 match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
1155 same bug. Such groups have to be quantified to be useful, or contained
1156 inside another quantified group. (If there's no repetition, the reference
1157 can never match.) The problem arises because, having left the group and
1158 moved on to the rest of the pattern, a later failure that backtracks into
1159 the group uses the captured value from the final iteration of the group
1160 rather than the correct earlier one. I have fixed this in PCRE by forcing
1161 any group that contains a reference to itself to be an atomic group; that
1162 is, there cannot be any backtracking into it once it has completed. This is
1163 similar to recursive and subroutine calls.
1164
1165
1166 Version 8.00 19-Oct-09
1167 ----------------------
1168
1169 1. The table for translating pcre_compile() error codes into POSIX error codes
1170 was out-of-date, and there was no check on the pcre_compile() error code
1171 being within the table. This could lead to an OK return being given in
1172 error.
1173
1174 2. Changed the call to open a subject file in pcregrep from fopen(pathname,
1175 "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
1176 in a Windows environment.
1177
1178 3. The pcregrep --count option prints the count for each file even when it is
1179 zero, as does GNU grep. However, pcregrep was also printing all files when
1180 --files-with-matches was added. Now, when both options are given, it prints
1181 counts only for those files that have at least one match. (GNU grep just
1182 prints the file name in this circumstance, but including the count seems
1183 more useful - otherwise, why use --count?) Also ensured that the
1184 combination -clh just lists non-zero counts, with no names.
1185
1186 4. The long form of the pcregrep -F option was incorrectly implemented as
1187 --fixed_strings instead of --fixed-strings. This is an incompatible change,
1188 but it seems right to fix it, and I didn't think it was worth preserving
1189 the old behaviour.
1190
1191 5. The command line items --regex=pattern and --regexp=pattern were not
1192 recognized by pcregrep, which required --regex pattern or --regexp pattern
1193 (with a space rather than an '='). The man page documented the '=' forms,
1194 which are compatible with GNU grep; these now work.
1195
1196 6. No libpcreposix.pc file was created for pkg-config; there was just
1197 libpcre.pc and libpcrecpp.pc. The omission has been rectified.
1198
1199 7. Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
1200 when UCP support is not needed, by modifying the Python script that
1201 generates it from Unicode data files. This should not matter if the module
1202 is correctly used as a library, but I received one complaint about 50K of
1203 unwanted data. My guess is that the person linked everything into his
1204 program rather than using a library. Anyway, it does no harm.
1205
1206 8. A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
1207 was a minimum greater than 1 for a wide character in a possessive
1208 repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
1209 which had an unlimited repeat of a nested, fixed maximum repeat of a wide
1210 character. Chaos in the form of incorrect output or a compiling loop could
1211 result.
1212
1213 9. The restrictions on what a pattern can contain when partial matching is
1214 requested for pcre_exec() have been removed. All patterns can now be
1215 partially matched by this function. In addition, if there are at least two
1216 slots in the offset vector, the offset of the earliest inspected character
1217 for the match and the offset of the end of the subject are set in them when
1218 PCRE_ERROR_PARTIAL is returned.
1219
1220 10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
1221 synonymous with PCRE_PARTIAL, for backwards compatibility, and
1222 PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
1223 and may be more useful for multi-segment matching.
1224
1225 11. Partial matching with pcre_exec() is now more intuitive. A partial match
1226 used to be given if ever the end of the subject was reached; now it is
1227 given only if matching could not proceed because another character was
1228 needed. This makes a difference in some odd cases such as Z(*FAIL) with the
1229 string "Z", which now yields "no match" instead of "partial match". In the
1230 case of pcre_dfa_exec(), "no match" is given if every matching path for the
1231 final character ended with (*FAIL).
1232
1233 12. Restarting a match using pcre_dfa_exec() after a partial match did not work
1234 if the pattern had a "must contain" character that was already found in the
1235 earlier partial match, unless partial matching was again requested. For
1236 example, with the pattern /dog.(body)?/, the "must contain" character is
1237 "g". If the first part-match was for the string "dog", restarting with
1238 "sbody" failed. This bug has been fixed.
1239
1240 13. The string returned by pcre_dfa_exec() after a partial match has been
1241 changed so that it starts at the first inspected character rather than the
1242 first character of the match. This makes a difference only if the pattern
1243 starts with a lookbehind assertion or \b or \B (\K is not supported by
1244 pcre_dfa_exec()). It's an incompatible change, but it makes the two
1245 matching functions compatible, and I think it's the right thing to do.
1246
1247 14. Added a pcredemo man page, created automatically from the pcredemo.c file,
1248 so that the demonstration program is easily available in environments where
1249 PCRE has not been installed from source.
1250
1251 15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
1252 libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
1253 library.
1254
1255 16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
1256 It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
1257 is not the first non-POSIX option to be added. Clearly some people find
1258 these options useful.
1259
1260 17. If a caller to the POSIX matching function regexec() passes a non-zero
1261 value for nmatch with a NULL value for pmatch, the value of
1262 nmatch is forced to zero.
1263
1264 18. RunGrepTest did not have a test for the availability of the -u option of
1265 the diff command, as RunTest does. It now checks in the same way as
1266 RunTest, and also checks for the -b option.
1267
1268 19. If an odd number of negated classes containing just a single character
1269 interposed, within parentheses, between a forward reference to a named
1270 subpattern and the definition of the subpattern, compilation crashed with
1271 an internal error, complaining that it could not find the referenced
1272 subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
1273 [The bug was that it was starting one character too far in when skipping
1274 over the character class, thus treating the ] as data rather than
1275 terminating the class. This meant it could skip too much.]
1276
1277 20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
1278 /g option in pcretest when the pattern contains \K, which makes it possible
1279 to have an empty string match not at the start, even when the pattern is
1280 anchored. Updated pcretest and pcredemo to use this option.
1281
1282 21. If the maximum number of capturing subpatterns in a recursion was greater
1283 than the maximum at the outer level, the higher number was returned, but
1284 with unset values at the outer level. The correct (outer level) value is
1285 now given.
1286
1287 22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
1288 PCRE did not set those parentheses (unlike Perl). I have now found a way to
1289 make it do so. The string so far is captured, making this feature
1290 compatible with Perl.
1291
1292 23. The tests have been re-organized, adding tests 11 and 12, to make it
1293 possible to check the Perl 5.10 features against Perl 5.10.
1294
1295 24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
1296 pattern matches a fixed length string. PCRE did not allow this; now it
1297 does. Neither allows recursion.
1298
1299 25. I finally figured out how to implement a request to provide the minimum
1300 length of subject string that was needed in order to match a given pattern.
1301 (It was back references and recursion that I had previously got hung up
1302 on.) This code has now been added to pcre_study(); it finds a lower bound
1303 to the length of subject needed. It is not necessarily the greatest lower
1304 bound, but using it to avoid searching strings that are too short does give
1305 some useful speed-ups. The value is available to calling programs via
1306 pcre_fullinfo().
1307
1308 26. While implementing 25, I discovered to my embarrassment that pcretest had
1309 not been passing the result of pcre_study() to pcre_dfa_exec(), so the
1310 study optimizations had never been tested with that matching function.
1311 Oops. What is worse, even when it was passed study data, there was a bug in
1312 pcre_dfa_exec() that meant it never actually used it. Double oops. There
1313 were also very few tests of studied patterns with pcre_dfa_exec().
1314
1315 27. If (?| is used to create subpatterns with duplicate numbers, they are now
1316 allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
1317 on the other side of the coin, they are no longer allowed to have different
1318 names, because these cannot be distinguished in PCRE, and this has caused
1319 confusion. (This is a difference from Perl.)
1320
1321 28. When duplicate subpattern names are present (necessarily with different
1322 numbers, as required by 27 above), and a test is made by name in a
1323 conditional pattern, either for a subpattern having been matched, or for
1324 recursion in such a pattern, all the associated numbered subpatterns are
1325 tested, and the overall condition is true if the condition is true for any
1326 one of them. This is the way Perl works, and is also more like the way
1327 testing by number works.
1328
1329
1330 Version 7.9 11-Apr-09
1331 ---------------------
1332
1333 1. When building with support for bzlib/zlib (pcregrep) and/or readline
1334 (pcretest), all targets were linked against these libraries. This included
1335 libpcre, libpcreposix, and libpcrecpp, even though they do not use these
1336 libraries. This caused unwanted dependencies to be created. This problem
1337 has been fixed, and now only pcregrep is linked with bzlib/zlib and only
1338 pcretest is linked with readline.
1339
1340 2. The "typedef int BOOL" in pcre_internal.h that was included inside the
1341 "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
1342 moved outside it again, because FALSE and TRUE are already defined in AIX,
1343 but BOOL is not.
1344
1345 3. The pcre_config() function was treating the PCRE_MATCH_LIMIT and
1346 PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
1347
1348 4. The pcregrep documentation said spaces were inserted as well as colons (or
1349 hyphens) following file names and line numbers when outputting matching
1350 lines. This is not true; no spaces are inserted. I have also clarified the
1351 wording for the --colour (or --color) option.
1352
1353 5. In pcregrep, when --colour was used with -o, the list of matching strings
1354 was not coloured; this is different to GNU grep, so I have changed it to be
1355 the same.
1356
1357 6. When --colo(u)r was used in pcregrep, only the first matching substring in
1358 each matching line was coloured. Now it goes on to look for further matches
1359 of any of the test patterns, which is the same behaviour as GNU grep.
1360
1361 7. A pattern that could match an empty string could cause pcregrep to loop; it
1362 doesn't make sense to accept an empty string match in pcregrep, so I have
1363 locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
1364 seems to be how GNU grep behaves.
1365
1366 8. The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
1367 start or after a newline", because the conditional assertion was not being
1368 correctly handled. The rule now is that both the assertion and what follows
1369 in the first alternative must satisfy the test.
1370
1371 9. If auto-callout was enabled in a pattern with a conditional group whose
1372 condition was an assertion, PCRE could crash during matching, both with
1373 pcre_exec() and pcre_dfa_exec().
1374
1375 10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
1376 used for matching.
1377
1378 11. Unicode property support in character classes was not working for
1379 characters (bytes) greater than 127 when not in UTF-8 mode.
1380
1381 12. Added the -M command line option to pcretest.
1382
1383 14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
1384
1385 15. Added the PCRE_NO_START_OPTIMIZE match-time option.
1386
1387 16. Added comments and documentation about mis-use of no_arg in the C++
1388 wrapper.
1389
1390 17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
1391 from Martin Jerabek that uses macro names for all relevant character and
1392 string constants.
1393
1394 18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
1395 SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
1396 SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
1397 these, but not everybody uses configure.
1398
1399 19. A conditional group that had only one branch was not being correctly
1400 recognized as an item that could match an empty string. This meant that an
1401 enclosing group might also not be so recognized, causing infinite looping
1402 (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
1403 with the subject "ab", where knowledge that the repeated group can match
1404 nothing is needed in order to break the loop.
1405
1406 20. If a pattern that was compiled with callouts was matched using pcre_dfa_
1407 exec(), but without supplying a callout function, matching went wrong.
1408
1409 21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
1410 leak if the size of the offset vector was greater than 30. When the vector
1411 is smaller, the saved offsets during recursion go onto a local stack
1412 vector, but for larger vectors malloc() is used. It was failing to free
1413 when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
1414 error, in fact).
1415
1416 22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
1417 heapframe that is used only when UTF-8 support is enabled. This caused no
1418 problem, but was untidy.
1419
1420 23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
1421 CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
1422 included within another project.
1423
1424 24. Steven Van Ingelgem's patches to add more options to the CMake support,
1425 slightly modified by me:
1426
1427 (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
1428 not building pcregrep.
1429
1430 (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
1431 if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
1432
1433 25. Forward references, both numeric and by name, in patterns that made use of
1434 duplicate group numbers, could behave incorrectly or give incorrect errors,
1435 because when scanning forward to find the reference group, PCRE was not
1436 taking into account the duplicate group numbers. A pattern such as
1437 ^X(?3)(a)(?|(b)|(q))(Y) is an example.
1438
1439 26. Changed a few more instances of "const unsigned char *" to USPTR, making
1440 the feature of a custom pointer more persuasive (as requested by a user).
1441
1442 27. Wrapped the definitions of fileno and isatty for Windows, which appear in
1443 pcretest.c, inside #ifndefs, because it seems they are sometimes already
1444 pre-defined.
1445
1446 28. Added support for (*UTF8) at the start of a pattern.
1447
1448 29. Arrange for flags added by the "release type" setting in CMake to be shown
1449 in the configuration summary.
1450
1451
1452 Version 7.8 05-Sep-08
1453 ---------------------
1454
1455 1. Replaced UCP searching code with optimized version as implemented for Ad
1456 Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
1457 stage table and inline lookup instead of a function, giving speed ups of 2
1458 to 5 times on some simple patterns that I tested. Permission was given to
1459 distribute the MultiStage2.py script that generates the tables (it's not in
1460 the tarball, but is in the Subversion repository).
1461
1462 2. Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
1463 scripts.
1464
1465 3. Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
1466 a group with a zero qualifier. The result of the study could be incorrect,
1467 or the function might crash, depending on the pattern.
1468
1469 4. Caseless matching was not working for non-ASCII characters in back
1470 references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
1471 It now works when Unicode Property Support is available.
1472
1473 5. In pcretest, an escape such as \x{de} in the data was always generating
1474 a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
1475 non-UTF-8 mode. If the value is greater than 255, it gives a warning about
1476 truncation.
1477
1478 6. Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
1479
1480 7. Added two (int) casts to pcregrep when printing the difference of two
1481 pointers, in case they are 64-bit values.
1482
1483 8. Added comments about Mac OS X stack usage to the pcrestack man page and to
1484 test 2 if it fails.
1485
1486 9. Added PCRE_CALL_CONVENTION just before the names of all exported functions,
1487 and a #define of that name to empty if it is not externally set. This is to
1488 allow users of MSVC to set it if necessary.
1489
1490 10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
1491 the convenience functions in the pcre_get.c source file.
1492
1493 11. An option change at the start of a pattern that had top-level alternatives
1494 could cause overwriting and/or a crash. This command provoked a crash in
1495 some environments:
1496
1497 printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
1498
1499 This potential security problem was recorded as CVE-2008-2371.
1500
1501 12. For a pattern where the match had to start at the beginning or immediately
1502 after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
1503 pcre_dfa_exec() could read past the end of the passed subject if there was
1504 no match. To help with detecting such bugs (e.g. with valgrind), I modified
1505 pcretest so that it places the subject at the end of its malloc-ed buffer.
1506
1507 13. The change to pcretest in 12 above threw up a couple more cases when pcre_
1508 exec() might read past the end of the data buffer in UTF-8 mode.
1509
1510 14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
1511 the data contained the byte 0x85 as part of a UTF-8 character within its
1512 first line. This applied both to normal and DFA matching.
1513
1514 15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
1515 /^[^d]*?$/8 failed to match "abc".
1516
1517 16. Added a missing copyright notice to pcrecpp_internal.h.
1518
1519 17. Make it more clear in the documentation that values returned from
1520 pcre_exec() in ovector are byte offsets, not character counts.
1521
1522 18. Tidied a few places to stop certain compilers from issuing warnings.
1523
1524 19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
1525 supplied by Stefan Weber. I made a further small update for 7.8 because
1526 there is a change of source arrangements: the pcre_searchfuncs.c module is
1527 replaced by pcre_ucd.c.
1528
1529
1530 Version 7.7 07-May-08
1531 ---------------------
1532
1533 1. Applied Craig's patch to sort out a long long problem: "If we can't convert
1534 a string to a long long, pretend we don't even have a long long." This is
1535 done by checking for the strtoq, strtoll, and _strtoi64 functions.
1536
1537 2. Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
1538 pre-7.6 versions, which defined a global no_arg variable instead of putting
1539 it in the RE class. (See also #8 below.)
1540
1541 3. Remove a line of dead code, identified by coverity and reported by Nuno
1542 Lopes.
1543
1544 4. Fixed two related pcregrep bugs involving -r with --include or --exclude:
1545
1546 (1) The include/exclude patterns were being applied to the whole pathnames
1547 of files, instead of just to the final components.
1548
1549 (2) If there was more than one level of directory, the subdirectories were
1550 skipped unless they satisfied the include/exclude conditions. This is
1551 inconsistent with GNU grep (and could even be seen as contrary to the
1552 pcregrep specification - which I improved to make it absolutely clear).
1553 The action now is always to scan all levels of directory, and just
1554 apply the include/exclude patterns to regular files.
1555
1556 5. Added the --include_dir and --exclude_dir patterns to pcregrep, and used
1557 --exclude_dir in the tests to avoid scanning .svn directories.
1558
1559 6. Applied Craig's patch to the QuoteMeta function so that it escapes the
1560 NUL character as backslash + 0 rather than backslash + NUL, because PCRE
1561 doesn't support NULs in patterns.
1562
1563 7. Added some missing "const"s to declarations of static tables in
1564 pcre_compile.c and pcre_dfa_exec.c.
1565
1566 8. Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
1567 caused by fix #2 above. (Subsequently also a second patch to fix the
1568 first patch. And a third patch - this was a messy problem.)
1569
1570 9. Applied Craig's patch to remove the use of push_back().
1571
1572 10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
1573 matching function regexec().
1574
1575 11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
1576 which, however, unlike Perl's \g{...}, are subroutine calls, not back
1577 references. PCRE supports relative numbers with this syntax (I don't think
1578 Oniguruma does).
1579
1580 12. Previously, a group with a zero repeat such as (...){0} was completely
1581 omitted from the compiled regex. However, this means that if the group
1582 was called as a subroutine from elsewhere in the pattern, things went wrong
1583 (an internal error was given). Such groups are now left in the compiled
1584 pattern, with a new opcode that causes them to be skipped at execution
1585 time.
1586
1587 13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
1588 to the way PCRE behaves:
1589
1590 (a) A lone ] character is dis-allowed (Perl treats it as data).
1591
1592 (b) A back reference to an unmatched subpattern matches an empty string
1593 (Perl fails the current match path).
1594
1595 (c) A data ] in a character class must be notated as \] because if the
1596 first data character in a class is ], it defines an empty class. (In
1597 Perl it is not possible to have an empty class.) The empty class []
1598 never matches; it forces failure and is equivalent to (*FAIL) or (?!).
1599 The negative empty class [^] matches any one character, independently
1600 of the DOTALL setting.
1601
1602 14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
1603 non-existent subpattern following a character class starting with ']' and
1604 containing () gave an internal compiling error instead of "reference to
1605 non-existent subpattern". Fortunately, when the pattern did exist, the
1606 compiled code was correct. (When scanning forwards to check for the
1607 existencd of the subpattern, it was treating the data ']' as terminating
1608 the class, so got the count wrong. When actually compiling, the reference
1609 was subsequently set up correctly.)
1610
1611 15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
1612 it was being rejected as not supported by pcre_dfa_exec(), even though
1613 other assertions are supported. I have made pcre_dfa_exec() support
1614 (*FAIL).
1615
1616 16. The implementation of 13c above involved the invention of a new opcode,
1617 OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
1618 cannot be changed at match time, I realized I could make a small
1619 improvement to matching performance by compiling OP_ALLANY instead of
1620 OP_ANY for "." when DOTALL was set, and then removing the runtime tests
1621 on the OP_ANY path.
1622
1623 17. Compiling pcretest on Windows with readline support failed without the
1624 following two fixes: (1) Make the unistd.h include conditional on
1625 HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
1626
1627 18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
1628 ncurses library to be included for pcretest when ReadLine support is
1629 requested, but also to allow for it to be overridden. This patch came from
1630 Daniel Bergström.
1631
1632 19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
1633 as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
1634 any errors with the current Unicode tables. Thanks to Peter Kankowski for
1635 spotting this.
1636
1637
1638 Version 7.6 28-Jan-08
1639 ---------------------
1640
1641 1. A character class containing a very large number of characters with
1642 codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
1643 overflow.
1644
1645 2. Patch to cut out the "long long" test in pcrecpp_unittest when
1646 HAVE_LONG_LONG is not defined.
1647
1648 3. Applied Christian Ehrlicher's patch to update the CMake build files to
1649 bring them up to date and include new features. This patch includes:
1650
1651 - Fixed PH's badly added libz and libbz2 support.
1652 - Fixed a problem with static linking.
1653 - Added pcredemo. [But later removed - see 7 below.]
1654 - Fixed dftables problem and added an option.
1655 - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
1656 HAVE_LONG_LONG.
1657 - Added readline support for pcretest.
1658 - Added an listing of the option settings after cmake has run.
1659
1660 4. A user submitted a patch to Makefile that makes it easy to create
1661 "pcre.dll" under mingw when using Configure/Make. I added stuff to
1662 Makefile.am that cause it to include this special target, without
1663 affecting anything else. Note that the same mingw target plus all
1664 the other distribution libraries and programs are now supported
1665 when configuring with CMake (see 6 below) instead of with
1666 Configure/Make.
1667
1668 5. Applied Craig's patch that moves no_arg into the RE class in the C++ code.
1669 This is an attempt to solve the reported problem "pcrecpp::no_arg is not
1670 exported in the Windows port". It has not yet been confirmed that the patch
1671 solves the problem, but it does no harm.
1672
1673 6. Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
1674 NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
1675 with CMake, and also correct the comment about stack recursion.
1676
1677 7. Remove the automatic building of pcredemo from the ./configure system and
1678 from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
1679 of a program that users should build themselves after PCRE is installed, so
1680 building it automatically is not really right. What is more, it gave
1681 trouble in some build environments.
1682
1683 8. Further tidies to CMakeLists.txt from Sheri and Christian.
1684
1685
1686 Version 7.5 10-Jan-08
1687 ---------------------
1688
1689 1. Applied a patch from Craig: "This patch makes it possible to 'ignore'
1690 values in parens when parsing an RE using the C++ wrapper."
1691
1692 2. Negative specials like \S did not work in character classes in UTF-8 mode.
1693 Characters greater than 255 were excluded from the class instead of being
1694 included.
1695
1696 3. The same bug as (2) above applied to negated POSIX classes such as
1697 [:^space:].
1698
1699 4. PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
1700 defined or documented. It seems to have been a typo for PCRE_STATIC, so
1701 I have changed it.
1702
1703 5. The construct (?&) was not diagnosed as a syntax error (it referenced the
1704 first named subpattern) and a construct such as (?&a) would reference the
1705 first named subpattern whose name started with "a" (in other words, the
1706 length check was missing). Both these problems are fixed. "Subpattern name
1707 expected" is now given for (?&) (a zero-length name), and this patch also
1708 makes it give the same error for \k'' (previously it complained that that
1709 was a reference to a non-existent subpattern).
1710
1711 6. The erroneous patterns (?+-a) and (?-+a) give different error messages;
1712 this is right because (?- can be followed by option settings as well as by
1713 digits. I have, however, made the messages clearer.
1714
1715 7. Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
1716 than the number used in the conditional) now cause a compile-time error.
1717 This is actually not compatible with Perl, which accepts such patterns, but
1718 treats the conditional as always being FALSE (as PCRE used to), but it
1719 seems to me that giving a diagnostic is better.
1720
1721 8. Change "alphameric" to the more common word "alphanumeric" in comments
1722 and messages.
1723
1724 9. Fix two occurrences of "backslash" in comments that should have been
1725 "backspace".
1726
1727 10. Remove two redundant lines of code that can never be obeyed (their function
1728 was moved elsewhere).
1729
1730 11. The program that makes PCRE's Unicode character property table had a bug
1731 which caused it to generate incorrect table entries for sequences of
1732 characters that have the same character type, but are in different scripts.
1733 It amalgamated them into a single range, with the script of the first of
1734 them. In other words, some characters were in the wrong script. There were
1735 thirteen such cases, affecting characters in the following ranges:
1736
1737 U+002b0 - U+002c1
1738 U+0060c - U+0060d
1739 U+0061e - U+00612
1740 U+0064b - U+0065e
1741 U+0074d - U+0076d
1742 U+01800 - U+01805
1743 U+01d00 - U+01d77
1744 U+01d9b - U+01dbf
1745 U+0200b - U+0200f
1746 U+030fc - U+030fe
1747 U+03260 - U+0327f
1748 U+0fb46 - U+0fbb1
1749 U+10450 - U+1049d
1750
1751 12. The -o option (show only the matching part of a line) for pcregrep was not
1752 compatible with GNU grep in that, if there was more than one match in a
1753 line, it showed only the first of them. It now behaves in the same way as
1754 GNU grep.
1755
1756 13. If the -o and -v options were combined for pcregrep, it printed a blank
1757 line for every non-matching line. GNU grep prints nothing, and pcregrep now
1758 does the same. The return code can be used to tell if there were any
1759 non-matching lines.
1760
1761 14. Added --file-offsets and --line-offsets to pcregrep.
1762
1763 15. The pattern (?=something)(?R) was not being diagnosed as a potentially
1764 infinitely looping recursion. The bug was that positive lookaheads were not
1765 being skipped when checking for a possible empty match (negative lookaheads
1766 and both kinds of lookbehind were skipped).
1767
1768 16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
1769 inclusion of <windows.h> to before rather than after the definition of
1770 INVALID_FILE_ATTRIBUTES (patch from David Byron).
1771
1772 17. Specifying a possessive quantifier with a specific limit for a Unicode
1773 character property caused pcre_compile() to compile bad code, which led at
1774 runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
1775 are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
1776 caused the error; without that there was no problem.
1777
1778 18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
1779
1780 19. Added --enable-pcretest-libreadline.
1781
1782 20. In pcrecpp.cc, the variable 'count' was incremented twice in
1783 RE::GlobalReplace(). As a result, the number of replacements returned was
1784 double what it should be. I removed one of the increments, but Craig sent a
1785 later patch that removed the other one (the right fix) and added unit tests
1786 that check the return values (which was not done before).
1787
1788 21. Several CMake things:
1789
1790 (1) Arranged that, when cmake is used on Unix, the libraries end up with
1791 the names libpcre and libpcreposix, not just pcre and pcreposix.
1792
1793 (2) The above change means that pcretest and pcregrep are now correctly
1794 linked with the newly-built libraries, not previously installed ones.
1795
1796 (3) Added PCRE_SUPPORT_LIBREADLINE, PCRE_SUPPORT_LIBZ, PCRE_SUPPORT_LIBBZ2.
1797
1798 22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
1799 crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
1800 UTF-8 newline character). The key issue is that the pattern starts .*;
1801 this means that the match must be either at the beginning, or after a
1802 newline. The bug was in the code for advancing after a failed match and
1803 checking that the new position followed a newline. It was not taking
1804 account of UTF-8 characters correctly.
1805
1806 23. PCRE was behaving differently from Perl in the way it recognized POSIX
1807 character classes. PCRE was not treating the sequence [:...:] as a
1808 character class unless the ... were all letters. Perl, however, seems to
1809 allow any characters between [: and :], though of course it rejects as
1810 unknown any "names" that contain non-letters, because all the known class
1811 names consist only of letters. Thus, Perl gives an error for [[:1234:]],
1812 for example, whereas PCRE did not - it did not recognize a POSIX character
1813 class. This seemed a bit dangerous, so the code has been changed to be
1814 closer to Perl. The behaviour is not identical to Perl, because PCRE will
1815 diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
1816 treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
1817 Perl does, and where it didn't before.
1818
1819 24. Rewrite so as to remove the single use of %n from pcregrep because in some
1820 Windows environments %n is disabled by default.
1821
1822
1823 Version 7.4 21-Sep-07
1824 ---------------------
1825
1826 1. Change 7.3/28 was implemented for classes by looking at the bitmap. This
1827 means that a class such as [\s] counted as "explicit reference to CR or
1828 LF". That isn't really right - the whole point of the change was to try to
1829 help when there was an actual mention of one of the two characters. So now
1830 the change happens only if \r or \n (or a literal CR or LF) character is
1831 encountered.
1832
1833 2. The 32-bit options word was also used for 6 internal flags, but the numbers
1834 of both had grown to the point where there were only 3 bits left.
1835 Fortunately, there was spare space in the data structure, and so I have
1836 moved the internal flags into a new 16-bit field to free up more option
1837 bits.
1838
1839 3. The appearance of (?J) at the start of a pattern set the DUPNAMES option,
1840 but did not set the internal JCHANGED flag - either of these is enough to
1841 control the way the "get" function works - but the PCRE_INFO_JCHANGED
1842 facility is supposed to tell if (?J) was ever used, so now (?J) at the
1843 start sets both bits.
1844
1845 4. Added options (at build time, compile time, exec time) to change \R from
1846 matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
1847
1848 5. doc/pcresyntax.html was missing from the distribution.
1849
1850 6. Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
1851 compatibility, even though it is no longer used.
1852
1853 7. Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
1854 strtoull to pcrecpp.cc to select the available functions in WIN32 when the
1855 windows.h file is present (where different names are used). [This was
1856 reversed later after testing - see 16 below.]
1857
1858 8. Changed all #include <config.h> to #include "config.h". There were also
1859 some further <pcre.h> cases that I changed to "pcre.h".
1860
1861 9. When pcregrep was used with the --colour option, it missed the line ending
1862 sequence off the lines that it output.
1863
1864 10. It was pointed out to me that arrays of string pointers cause lots of
1865 relocations when a shared library is dynamically loaded. A technique of
1866 using a single long string with a table of offsets can drastically reduce
1867 these. I have refactored PCRE in four places to do this. The result is
1868 dramatic:
1869
1870 Originally: 290
1871 After changing UCP table: 187
1872 After changing error message table: 43
1873 After changing table of "verbs" 36
1874 After changing table of Posix names 22
1875
1876 Thanks to the folks working on Gregex for glib for this insight.
1877
1878 11. --disable-stack-for-recursion caused compiling to fail unless -enable-
1879 unicode-properties was also set.
1880
1881 12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
1882
1883 13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
1884 checked only for CRLF.
1885
1886 14. Added casts to pcretest.c to avoid compiler warnings.
1887
1888 15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
1889
1890 16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
1891 and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
1892 entirely. This removes changes made in 7 above.
1893
1894 17. The CMake files have been updated, and there is now more information about
1895 building with CMake in the NON-UNIX-USE document.
1896
1897
1898 Version 7.3 28-Aug-07
1899 ---------------------
1900
1901 1. In the rejigging of the build system that eventually resulted in 7.1, the
1902 line "#include <pcre.h>" was included in pcre_internal.h. The use of angle
1903 brackets there is not right, since it causes compilers to look for an
1904 installed pcre.h, not the version that is in the source that is being
1905 compiled (which of course may be different). I have changed it back to:
1906
1907 #include "pcre.h"
1908
1909 I have a vague recollection that the change was concerned with compiling in
1910 different directories, but in the new build system, that is taken care of
1911 by the VPATH setting the Makefile.
1912
1913 2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
1914 when the subject happened to end in the byte 0x85 (e.g. if the last
1915 character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
1916 characters but of course it shouldn't be taken as a newline when it is part
1917 of another character. The bug was that, for an unlimited repeat of . in
1918 not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
1919 characters when looking for a newline.
1920
1921 3. A small performance improvement in the DOTALL UTF-8 mode .* case.
1922
1923 4. Debugging: adjusted the names of opcodes for different kinds of parentheses
1924 in debug output.
1925
1926 5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
1927 long printing in the pcrecpp unittest when running under MinGW.
1928
1929 6. ESC_K was left out of the EBCDIC table.
1930
1931 7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
1932 parentheses; I made it 1000, which seemed large enough. Unfortunately, the
1933 limit also applies to "virtual nesting" when a pattern is recursive, and in
1934 this case 1000 isn't so big. I have been able to remove this limit at the
1935 expense of backing off one optimization in certain circumstances. Normally,
1936 when pcre_exec() would call its internal match() function recursively and
1937 immediately return the result unconditionally, it uses a "tail recursion"
1938 feature to save stack. However, when a subpattern that can match an empty
1939 string has an unlimited repetition quantifier, it no longer makes this
1940 optimization. That gives it a stack frame in which to save the data for
1941 checking that an empty string has been matched. Previously this was taken
1942 from the 1000-entry workspace that had been reserved. So now there is no
1943 explicit limit, but more stack is used.
1944
1945 8. Applied Daniel's patches to solve problems with the import/export magic
1946 syntax that is required for Windows, and which was going wrong for the
1947 pcreposix and pcrecpp parts of the library. These were overlooked when this
1948 problem was solved for the main library.
1949
1950 9. There were some crude static tests to avoid integer overflow when computing
1951 the size of patterns that contain repeated groups with explicit upper
1952 limits. As the maximum quantifier is 65535, the maximum group length was
1953 set at 30,000 so that the product of these two numbers did not overflow a
1954 32-bit integer. However, it turns out that people want to use groups that
1955 are longer than 30,000 bytes (though not repeat them that many times).
1956 Change 7.0/17 (the refactoring of the way the pattern size is computed) has
1957 made it possible to implement the integer overflow checks in a much more
1958 dynamic way, which I have now done. The artificial limitation on group
1959 length has been removed - we now have only the limit on the total length of
1960 the compiled pattern, which depends on the LINK_SIZE setting.
1961
1962 10. Fixed a bug in the documentation for get/copy named substring when
1963 duplicate names are permitted. If none of the named substrings are set, the
1964 functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
1965 empty string.
1966
1967 11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E
1968 instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error,
1969 because the ] is interpreted as the first data character and the
1970 terminating ] is not found. PCRE has been made compatible with Perl in this
1971 regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could
1972 cause memory overwriting.
1973
1974 10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty
1975 string has been matched (to stop an infinite loop). It was not recognizing
1976 a conditional subpattern that could match an empty string if that
1977 subpattern was within another subpattern. For example, it looped when
1978 trying to match (((?(1)X|))*) but it was OK with ((?(1)X|)*) where the
1979 condition was not nested. This bug has been fixed.
1980
1981 12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
1982 past the start of the subject in the presence of bytes with the top bit
1983 set, for example "\x8aBCD".
1984
1985 13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
1986 (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
1987
1988 14. Optimized (?!) to (*FAIL).
1989
1990 15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
1991 This restricts code points to be within the range 0 to 0x10FFFF, excluding
1992 the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
1993 full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
1994 does: it's just the validity check that is more restrictive.
1995
1996 16. Inserted checks for integer overflows during escape sequence (backslash)
1997 processing, and also fixed erroneous offset values for syntax errors during
1998 backslash processing.
1999
2000 17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
2001 for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
2002
2003 18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
2004 caused an overrun.
2005
2006 19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
2007 something other than just ASCII characters) inside a group that had an
2008 unlimited repeat caused a loop at compile time (while checking to see
2009 whether the group could match an empty string).
2010
2011 20. Debugging a pattern containing \p or \P could cause a crash. For example,
2012 [\P{Any}] did so. (Error in the code for printing property names.)
2013
2014 21. An orphan \E inside a character class could cause a crash.
2015
2016 22. A repeated capturing bracket such as (A)? could cause a wild memory
2017 reference during compilation.
2018
2019 23. There are several functions in pcre_compile() that scan along a compiled
2020 expression for various reasons (e.g. to see if it's fixed length for look
2021 behind). There were bugs in these functions when a repeated \p or \P was
2022 present in the pattern. These operators have additional parameters compared
2023 with \d, etc, and these were not being taken into account when moving along
2024 the compiled data. Specifically:
2025
2026 (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
2027 length.
2028
2029 (b) An item such as \pL+ within a repeated group could cause crashes or
2030 loops.
2031
2032 (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
2033 "reference to non-existent subpattern" error.
2034
2035 (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
2036
2037 24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
2038 characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
2039
2040 25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
2041
2042 26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
2043 character were causing crashes (broken optimization).
2044
2045 27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
2046 \p or \P) caused a compile-time loop.
2047
2048 28. More problems have arisen in unanchored patterns when CRLF is a valid line
2049 break. For example, the unstudied pattern [\r\n]A does not match the string
2050 "\r\nA" because change 7.0/46 below moves the current point on by two
2051 characters after failing to match at the start. However, the pattern \nA
2052 *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
2053 the same is true. There doesn't seem any very clean way out of this, but
2054 what I have chosen to do makes the common cases work: PCRE now takes note
2055 of whether there can be an explicit match for \r or \n anywhere in the
2056 pattern, and if so, 7.0/46 no longer applies. As part of this change,
2057 there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
2058 pattern has explicit CR or LF references.
2059
2060 29. Added (*CR) etc for changing newline setting at start of pattern.
2061
2062
2063 Version 7.2 19-Jun-07
2064 ---------------------
2065
2066 1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
2067 which is apparently normally available under Windows.
2068
2069 2. Re-jig the pcregrep tests with different newline settings in an attempt
2070 to make them independent of the local environment's newline setting.
2071
2072 3. Add code to configure.ac to remove -g from the CFLAGS default settings.
2073
2074 4. Some of the "internals" tests were previously cut out when the link size
2075 was not 2, because the output contained actual offsets. The recent new
2076 "Z" feature of pcretest means that these can be cut out, making the tests
2077 usable with all link sizes.
2078
2079 5. Implemented Stan Switzer's goto replacement for longjmp() when not using
2080 stack recursion. This gives a massive performance boost under BSD, but just
2081 a small improvement under Linux. However, it saves one field in the frame
2082 in all cases.
2083
2084 6. Added more features from the forthcoming Perl 5.10:
2085
2086 (a) (?-n) (where n is a string of digits) is a relative subroutine or
2087 recursion call. It refers to the nth most recently opened parentheses.
2088
2089 (b) (?+n) is also a relative subroutine call; it refers to the nth next
2090 to be opened parentheses.
2091
2092 (c) Conditions that refer to capturing parentheses can be specified
2093 relatively, for example, (?(-2)... or (?(+3)...
2094
2095 (d) \K resets the start of the current match so that everything before
2096 is not part of it.
2097
2098 (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible).
2099
2100 (f) \g{name} is another synonym - part of Perl 5.10's unification of
2101 reference syntax.
2102
2103 (g) (?| introduces a group in which the numbering of parentheses in each
2104 alternative starts with the same number.
2105
2106 (h) \h, \H, \v, and \V match horizontal and vertical whitespace.
2107
2108 7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and
2109 PCRE_INFO_JCHANGED.
2110
2111 8. A pattern such as (.*(.)?)* caused pcre_exec() to fail by either not
2112 terminating or by crashing. Diagnosed by Viktor Griph; it was in the code
2113 for detecting groups that can match an empty string.
2114
2115 9. A pattern with a very large number of alternatives (more than several
2116 hundred) was running out of internal workspace during the pre-compile
2117 phase, where pcre_compile() figures out how much memory will be needed. A
2118 bit of new cunning has reduced the workspace needed for groups with
2119 alternatives. The 1000-alternative test pattern now uses 12 bytes of
2120 workspace instead of running out of the 4096 that are available.
2121
2122 10. Inserted some missing (unsigned int) casts to get rid of compiler warnings.
2123
2124 11. Applied patch from Google to remove an optimization that didn't quite work.
2125 The report of the bug said:
2126
2127 pcrecpp::RE("a*").FullMatch("aaa") matches, while
2128 pcrecpp::RE("a*?").FullMatch("aaa") does not, and
2129 pcrecpp::RE("a*?\\z").FullMatch("aaa") does again.
2130
2131 12. If \p or \P was used in non-UTF-8 mode on a character greater than 127
2132 it matched the wrong number of bytes.
2133
2134
2135 Version 7.1 24-Apr-07
2136 ---------------------
2137
2138 1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
2139 that is more "standard", making use of automake and other Autotools. There
2140 is some re-arrangement of the files and adjustment of comments consequent
2141 on this.
2142
2143 2. Part of the patch fixed a problem with the pcregrep tests. The test of -r
2144 for recursive directory scanning broke on some systems because the files
2145 are not scanned in any specific order and on different systems the order
2146 was different. A call to "sort" has been inserted into RunGrepTest for the
2147 approprate test as a short-term fix. In the longer term there may be an
2148 alternative.
2149
2150 3. I had an email from Eric Raymond about problems translating some of PCRE's
2151 man pages to HTML (despite the fact that I distribute HTML pages, some
2152 people do their own conversions for various reasons). The problems
2153 concerned the use of low-level troff macros .br and .in. I have therefore
2154 removed all such uses from the man pages (some were redundant, some could
2155 be replaced by .nf/.fi pairs). The 132html script that I use to generate
2156 HTML has been updated to handle .nf/.fi and to complain if it encounters
2157 .br or .in.
2158
2159 4. Updated comments in configure.ac that get placed in config.h.in and also
2160 arranged for config.h to be included in the distribution, with the name
2161 config.h.generic, for the benefit of those who have to compile without
2162 Autotools (compare pcre.h, which is now distributed as pcre.h.generic).
2163
2164 5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
2165 Weber: (1) pcre_internal.h was missing some function renames; (2) updated
2166 makevp.bat for the current PCRE, using the additional files
2167 makevp_c.txt, makevp_l.txt, and pcregexp.pas.
2168
2169 6. A Windows user reported a minor discrepancy with test 2, which turned out
2170 to be caused by a trailing space on an input line that had got lost in his
2171 copy. The trailing space was an accident, so I've just removed it.
2172
2173 7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told
2174 that is needed.
2175
2176 8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c)
2177 as "const" (a) because they are and (b) because it helps the PHP
2178 maintainers who have recently made a script to detect big data structures
2179 in the php code that should be moved to the .rodata section. I remembered
2180 to update Builducptable as well, so it won't revert if ucptable.h is ever
2181 re-created.
2182
2183 9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c,
2184 pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in
2185 order to be able to cut out the UTF-8 tables in the latter when UTF-8
2186 support is not required. This saves 1.5-2K of code, which is important in
2187 some applications.
2188
2189 Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c
2190 so as not to refer to the tables, even though these functions will never be
2191 called when UTF-8 support is disabled. Otherwise there are problems with a
2192 shared library.
2193
2194 10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:
2195
2196 (a) It was defining its arguments as char * instead of void *.
2197
2198 (b) It was assuming that all moves were upwards in memory; this was true
2199 a long time ago when I wrote it, but is no longer the case.
2200
2201 The emulated memove() is provided for those environments that have neither
2202 memmove() nor bcopy(). I didn't think anyone used it these days, but that
2203 is clearly not the case, as these two bugs were recently reported.
2204
2205 11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,
2206 and Detrail to create the HTML documentation, the .txt form of the man
2207 pages, and it removes trailing spaces from listed files. It also creates
2208 pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter
2209 case, it wraps all the #defines with #ifndefs. This script should be run
2210 before "make dist".
2211
2212 12. Fixed two fairly obscure bugs concerned with quantified caseless matching
2213 with Unicode property support.
2214
2215 (a) For a maximizing quantifier, if the two different cases of the
2216 character were of different lengths in their UTF-8 codings (there are
2217 some cases like this - I found 11), and the matching function had to
2218 back up over a mixture of the two cases, it incorrectly assumed they
2219 were both the same length.
2220
2221 (b) When PCRE was configured to use the heap rather than the stack for
2222 recursion during matching, it was not correctly preserving the data for
2223 the other case of a UTF-8 character when checking ahead for a match
2224 while processing a minimizing repeat. If the check also involved
2225 matching a wide character, but failed, corruption could cause an
2226 erroneous result when trying to check for a repeat of the original
2227 character.
2228
2229 13. Some tidying changes to the testing mechanism:
2230
2231 (a) The RunTest script now detects the internal link size and whether there
2232 is UTF-8 and UCP support by running ./pcretest -C instead of relying on
2233 values substituted by "configure". (The RunGrepTest script already did
2234 this for UTF-8.) The configure.ac script no longer substitutes the
2235 relevant variables.
2236
2237 (b) The debugging options /B and /D in pcretest show the compiled bytecode
2238 with length and offset values. This means that the output is different
2239 for different internal link sizes. Test 2 is skipped for link sizes
2240 other than 2 because of this, bypassing the problem. Unfortunately,
2241 there was also a test in test 3 (the locale tests) that used /B and
2242 failed for link sizes other than 2. Rather than cut the whole test out,
2243 I have added a new /Z option to pcretest that replaces the length and
2244 offset values with spaces. This is now used to make test 3 independent
2245 of link size. (Test 2 will be tidied up later.)
2246
2247 14. If erroroffset was passed as NULL to pcre_compile, it provoked a
2248 segmentation fault instead of returning the appropriate error message.
2249
2250 15. In multiline mode when the newline sequence was set to "any", the pattern
2251 ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
2252 This doesn't seem right; it now treats the CRLF combination as the line
2253 ending, and so does not match in that case. It's only a pattern such as ^$
2254 that would hit this one: something like ^ABC$ would have failed after \r
2255 and then tried again after \r\n.
2256
2257 16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
2258 in an attempt to make files that differ only in their line terminators
2259 compare equal. This works on Linux.
2260
2261 17. Under certain error circumstances pcregrep might try to free random memory
2262 as it exited. This is now fixed, thanks to valgrind.
2263
2264 19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
2265 "abc\r\n\r\n", it found an unwanted second match after the second \r. This
2266 was because its rules for how to advance for /g after matching an empty
2267 string at the end of a line did not allow for this case. They now check for
2268 it specially.
2269
2270 20. pcretest is supposed to handle patterns and data of any length, by
2271 extending its buffers when necessary. It was getting this wrong when the
2272 buffer for a data line had to be extended.
2273
2274 21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
2275 CRLF as a newline sequence.
2276
2277 22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
2278 out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
2279 I have nevertheless tidied it up.
2280
2281 23. Added some casts to kill warnings from HP-UX ia64 compiler.
2282
2283 24. Added a man page for pcre-config.
2284
2285
2286 Version 7.0 19-Dec-06
2287 ---------------------
2288
2289 1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by
2290 moving to gcc 4.1.1.
2291
2292 2. The -S option for pcretest uses setrlimit(); I had omitted to #include
2293 sys/time.h, which is documented as needed for this function. It doesn't
2294 seem to matter on Linux, but it showed up on some releases of OS X.
2295
2296 3. It seems that there are systems where bytes whose values are greater than
2297 127 match isprint() in the "C" locale. The "C" locale should be the
2298 default when a C program starts up. In most systems, only ASCII printing
2299 characters match isprint(). This difference caused the output from pcretest
2300 to vary, making some of the tests fail. I have changed pcretest so that:
2301
2302 (a) When it is outputting text in the compiled version of a pattern, bytes
2303 other than 32-126 are always shown as hex escapes.
2304
2305 (b) When it is outputting text that is a matched part of a subject string,
2306 it does the same, unless a different locale has been set for the match
2307 (using the /L modifier). In this case, it uses isprint() to decide.
2308
2309 4. Fixed a major bug that caused incorrect computation of the amount of memory
2310 required for a compiled pattern when options that changed within the
2311 pattern affected the logic of the preliminary scan that determines the
2312 length. The relevant options are -x, and -i in UTF-8 mode. The result was
2313 that the computed length was too small. The symptoms of this bug were
2314 either the PCRE error "internal error: code overflow" from pcre_compile(),
2315 or a glibc crash with a message such as "pcretest: free(): invalid next
2316 size (fast)". Examples of patterns that provoked this bug (shown in
2317 pcretest format) are:
2318
2319 /(?-x: )/x
2320 /(?x)(?-x: \s*#\s*)/
2321 /((?i)[\x{c0}])/8
2322 /(?i:[\x{c0}])/8
2323
2324 HOWEVER: Change 17 below makes this fix obsolete as the memory computation
2325 is now done differently.
2326
2327 5. Applied patches from Google to: (a) add a QuoteMeta function to the C++
2328 wrapper classes; (b) implement a new function in the C++ scanner that is
2329 more efficient than the old way of doing things because it avoids levels of
2330 recursion in the regex matching; (c) add a paragraph to the documentation
2331 for the FullMatch() function.
2332
2333 6. The escape sequence \n was being treated as whatever was defined as
2334 "newline". Not only was this contrary to the documentation, which states
2335 that \n is character 10 (hex 0A), but it also went horribly wrong when
2336 "newline" was defined as CRLF. This has been fixed.
2337
2338 7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c)
2339 was being set to -1 for the "end of line" case (supposedly a value that no
2340 character can have). Though this value is never used (the check for end of
2341 line is "zero bytes in current character"), it caused compiler complaints.
2342 I've changed it to 0xffffffff.
2343
2344 8. In pcre_version.c, the version string was being built by a sequence of
2345 C macros that, in the event of PCRE_PRERELEASE being defined as an empty
2346 string (as it is for production releases) called a macro with an empty
2347 argument. The C standard says the result of this is undefined. The gcc
2348 compiler treats it as an empty string (which was what was wanted) but it is
2349 reported that Visual C gives an error. The source has been hacked around to
2350 avoid this problem.
2351
2352 9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows
2353 builds of pcretest, and changed the call to _setmode() to use _O_BINARY
2354 instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all
2355 of them did).
2356
2357 10. Originally, pcretest opened its input and output without "b"; then I was
2358 told that "b" was needed in some environments, so it was added for release
2359 5.0 to both the input and output. (It makes no difference on Unix-like
2360 systems.) Later I was told that it is wrong for the input on Windows. I've
2361 now abstracted the modes into two macros, to make it easier to fiddle with
2362 them, and removed "b" from the input mode under Windows.
2363
2364 11. Added pkgconfig support for the C++ wrapper library, libpcrecpp.
2365
2366 12. Added -help and --help to pcretest as an official way of being reminded
2367 of the options.
2368
2369 13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in
2370 and pcrecpp.cc because they annoy compilers at high warning levels.
2371
2372 14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop.
2373
2374 15. Fixed an occurrence of == in configure.ac that should have been = (shell
2375 scripts are not C programs :-) and which was not noticed because it works
2376 on Linux.
2377
2378 16. pcretest is supposed to handle any length of pattern and data line (as one
2379 line or as a continued sequence of lines) by extending its input buffer if
2380 necessary. This feature was broken for very long pattern lines, leading to
2381 a string of junk being passed to pcre_compile() if the pattern was longer
2382 than about 50K.
2383
2384 17. I have done a major re-factoring of the way pcre_compile() computes the
2385 amount of memory needed for a compiled pattern. Previously, there was code
2386 that made a preliminary scan of the pattern in order to do this. That was
2387 OK when PCRE was new, but as the facilities have expanded, it has become
2388 harder and harder to keep it in step with the real compile phase, and there
2389 have been a number of bugs (see for example, 4 above). I have now found a
2390 cunning way of running the real compile function in a "fake" mode that
2391 enables it to compute how much memory it would need, while actually only
2392 ever using a few hundred bytes of working memory and without too many
2393 tests of the mode. This should make future maintenance and development
2394 easier. A side effect of this work is that the limit of 200 on the nesting
2395 depth of parentheses has been removed (though this was never a serious
2396 limitation, I suspect). However, there is a downside: pcre_compile() now
2397 runs more slowly than before (30% or more, depending on the pattern). I
2398 hope this isn't a big issue. There is no effect on runtime performance.
2399
2400 18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a
2401 newline (only possible for the last line of a file) and it was a
2402 pattern that set a locale (followed by /Lsomething), pcretest crashed.
2403
2404 19. Added additional timing features to pcretest. (1) The -tm option now times
2405 matching only, not compiling. (2) Both -t and -tm can be followed, as a
2406 separate command line item, by a number that specifies the number of
2407 repeats to use when timing. The default is 50000; this gives better
2408 precision, but takes uncomfortably long for very large patterns.
2409
2410 20. Extended pcre_study() to be more clever in cases where a branch of a
2411 subpattern has no definite first character. For example, (a*|b*)[cd] would
2412 previously give no result from pcre_study(). Now it recognizes that the
2413 first character must be a, b, c, or d.
2414
2415 21. There was an incorrect error "recursive call could loop indefinitely" if
2416 a subpattern (or the entire pattern) that was being tested for matching an
2417 empty string contained only one non-empty item after a nested subpattern.
2418 For example, the pattern (?>\x{100}*)\d(?R) provoked this error
2419 incorrectly, because the \d was being skipped in the check.
2420
2421 22. The pcretest program now has a new pattern option /B and a command line
2422 option -b, which is equivalent to adding /B to every pattern. This causes
2423 it to show the compiled bytecode, without the additional information that
2424 -d shows. The effect of -d is now the same as -b with -i (and similarly, /D
2425 is the same as /B/I).
2426
2427 23. A new optimization is now able automatically to treat some sequences such
2428 as a*b as a*+b. More specifically, if something simple (such as a character
2429 or a simple class like \d) has an unlimited quantifier, and is followed by
2430 something that cannot possibly match the quantified thing, the quantifier
2431 is automatically "possessified".
2432
2433 24. A recursive reference to a subpattern whose number was greater than 39
2434 went wrong under certain circumstances in UTF-8 mode. This bug could also
2435 have affected the operation of pcre_study().
2436
2437 25. Realized that a little bit of performance could be had by replacing
2438 (c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters.
2439
2440 26. Timing data from pcretest is now shown to 4 decimal places instead of 3.
2441
2442 27. Possessive quantifiers such as a++ were previously implemented by turning
2443 them into atomic groups such as ($>a+). Now they have their own opcodes,
2444 which improves performance. This includes the automatically created ones
2445 from 23 above.
2446
2447 28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a
2448 lookahead was broken if it was not anchored. PCRE was mistakenly expecting
2449 the first matched character to be a colon. This applied both to named and
2450 numbered groups.
2451
2452 29. The ucpinternal.h header file was missing its idempotency #ifdef.
2453
2454 30. I was sent a "project" file called libpcre.a.dev which I understand makes
2455 building PCRE on Windows easier, so I have included it in the distribution.
2456
2457 31. There is now a check in pcretest against a ridiculously large number being
2458 returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G
2459 loop, the loop is abandoned.
2460
2461 32. Forward references to subpatterns in conditions such as (?(2)...) where
2462 subpattern 2 is defined later cause pcre_compile() to search forwards in
2463 the pattern for the relevant set of parentheses. This search went wrong
2464 when there were unescaped parentheses in a character class, parentheses
2465 escaped with \Q...\E, or parentheses in a #-comment in /x mode.
2466
2467 33. "Subroutine" calls and backreferences were previously restricted to
2468 referencing subpatterns earlier in the regex. This restriction has now
2469 been removed.
2470
2471 34. Added a number of extra features that are going to be in Perl 5.10. On the
2472 whole, these are just syntactic alternatives for features that PCRE had
2473 previously implemented using the Python syntax or my own invention. The
2474 other formats are all retained for compatibility.
2475
2476 (a) Named groups can now be defined as (?<name>...) or (?'name'...) as well
2477 as (?P<name>...). The new forms, as well as being in Perl 5.10, are
2478 also .NET compatible.
2479
2480 (b) A recursion or subroutine call to a named group can now be defined as
2481 (?&name) as well as (?P>name).
2482
2483 (c) A backreference to a named group can now be defined as \k<name> or
2484 \k'name' as well as (?P=name). The new forms, as well as being in Perl
2485 5.10, are also .NET compatible.
2486
2487 (d) A conditional reference to a named group can now use the syntax
2488 (?(<name>) or (?('name') as well as (?(name).
2489
2490 (e) A "conditional group" of the form (?(DEFINE)...) can be used to define
2491 groups (named and numbered) that are never evaluated inline, but can be
2492 called as "subroutines" from elsewhere. In effect, the DEFINE condition
2493 is always false. There may be only one alternative in such a group.
2494
2495 (f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well
2496 as the simple (?(R). The condition is true only if the most recent
2497 recursion is that of the given number or name. It does not search out
2498 through the entire recursion stack.
2499
2500 (g) The escape \gN or \g{N} has been added, where N is a positive or
2501 negative number, specifying an absolute or relative reference.
2502
2503 35. Tidied to get rid of some further signed/unsigned compiler warnings and
2504 some "unreachable code" warnings.
2505
2506 36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other
2507 things, this adds five new scripts.
2508
2509 37. Perl ignores orphaned \E escapes completely. PCRE now does the same.
2510 There were also incompatibilities regarding the handling of \Q..\E inside
2511 character classes, for example with patterns like [\Qa\E-\Qz\E] where the
2512 hyphen was adjacent to \Q or \E. I hope I've cleared all this up now.
2513
2514 38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group
2515 matches an empty string, and forcibly breaks the loop. There were bugs in
2516 this code in non-simple cases. For a pattern such as ^(a()*)* matched
2517 against aaaa the result was just "a" rather than "aaaa", for example. Two
2518 separate and independent bugs (that affected different cases) have been
2519 fixed.
2520
2521 39. Refactored the code to abolish the use of different opcodes for small
2522 capturing bracket numbers. This is a tidy that I avoided doing when I
2523 removed the limit on the number of capturing brackets for 3.5 back in 2001.
2524 The new approach is not only tidier, it makes it possible to reduce the
2525 memory needed to fix the previous bug (38).
2526
2527 40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline
2528 sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when
2529 processing dot, circumflex, or dollar metacharacters, or #-comments in /x
2530 mode.
2531
2532 41. Add \R to match any Unicode newline sequence, as suggested in the Unicode
2533 report.
2534
2535 42. Applied patch, originally from Ari Pollak, modified by Google, to allow
2536 copy construction and assignment in the C++ wrapper.
2537
2538 43. Updated pcregrep to support "--newline=any". In the process, I fixed a
2539 couple of bugs that could have given wrong results in the "--newline=crlf"
2540 case.
2541
2542 44. Added a number of casts and did some reorganization of signed/unsigned int
2543 variables following suggestions from Dair Grant. Also renamed the variable
2544 "this" as "item" because it is a C++ keyword.
2545
2546 45. Arranged for dftables to add
2547
2548 #include "pcre_internal.h"
2549
2550 to pcre_chartables.c because without it, gcc 4.x may remove the array
2551 definition from the final binary if PCRE is built into a static library and
2552 dead code stripping is activated.
2553
2554 46. For an unanchored pattern, if a match attempt fails at the start of a
2555 newline sequence, and the newline setting is CRLF or ANY, and the next two
2556 characters are CRLF, advance by two characters instead of one.
2557
2558
2559 Version 6.7 04-Jul-06
2560 ---------------------
2561
2562 1. In order to handle tests when input lines are enormously long, pcretest has
2563 been re-factored so that it automatically extends its buffers when
2564 necessary. The code is crude, but this _is_ just a test program. The
2565 default size has been increased from 32K to 50K.
2566
2567 2. The code in pcre_study() was using the value of the re argument before
2568 testing it for NULL. (Of course, in any sensible call of the function, it
2569 won't be NULL.)
2570
2571 3. The memmove() emulation function in pcre_internal.h, which is used on
2572 systems that lack both memmove() and bcopy() - that is, hardly ever -
2573 was missing a "static" storage class specifier.
2574
2575 4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns
2576 containing an extended class (one that cannot be represented by a bitmap
2577 because it contains high-valued characters or Unicode property items, e.g.
2578 [\pZ]). Almost always one would set UTF-8 mode when processing such a
2579 pattern, but PCRE should not loop if you do not (it no longer does).
2580 [Detail: two cases were found: (a) a repeated subpattern containing an
2581 extended class; (b) a recursive reference to a subpattern that followed a
2582 previous extended class. It wasn't skipping over the extended class
2583 correctly when UTF-8 mode was not set.]
2584
2585 5. A negated single-character class was not being recognized as fixed-length
2586 in lookbehind assertions such as (?<=[^f]), leading to an incorrect
2587 compile error "lookbehind assertion is not fixed length".
2588
2589 6. The RunPerlTest auxiliary script was showing an unexpected difference
2590 between PCRE and Perl for UTF-8 tests. It turns out that it is hard to
2591 write a Perl script that can interpret lines of an input file either as
2592 byte characters or as UTF-8, which is what "perltest" was being required to
2593 do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you
2594 can't do is switch easily at run time between having the "use utf8;" pragma
2595 or not. In the end, I fudged it by using the RunPerlTest script to insert
2596 "use utf8;" explicitly for the UTF-8 tests.
2597
2598 7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at
2599 the end of the subject string, contrary to the documentation and to what
2600 Perl does. This was true of both matching functions. Now it matches only at
2601 the start of the subject and immediately after *internal* newlines.
2602
2603 8. A call of pcre_fullinfo() from pcretest to get the option bits was passing
2604 a pointer to an int instead of a pointer to an unsigned long int. This
2605 caused problems on 64-bit systems.
2606
2607 9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another
2608 instance of the 'standard' template library not being so standard".
2609
2610 10. There was no check on the number of named subpatterns nor the maximum
2611 length of a subpattern name. The product of these values is used to compute
2612 the size of the memory block for a compiled pattern. By supplying a very
2613 long subpattern name and a large number of named subpatterns, the size
2614 computation could be caused to overflow. This is now prevented by limiting
2615 the length of names to 32 characters, and the number of named subpatterns
2616 to 10,000.
2617
2618 11. Subpatterns that are repeated with specific counts have to be replicated in
2619 the compiled pattern. The size of memory for this was computed from the
2620 length of the subpattern and the repeat count. The latter is limited to
2621 65535, but there was no limit on the former, meaning that integer overflow
2622 could in principle occur. The compiled length of a repeated subpattern is
2623 now limited to 30,000 bytes in order to prevent this.
2624
2625 12. Added the optional facility to have named substrings with the same name.
2626
2627 13. Added the ability to use a named substring as a condition, using the
2628 Python syntax: (?(name)yes|no). This overloads (?(R)... and names that
2629 are numbers (not recommended). Forward references are permitted.
2630
2631 14. Added forward references in named backreferences (if you see what I mean).
2632
2633 15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the
2634 pattern could run off the end of the subject. For example, the pattern
2635 "(?s)(.{1,5})"8 did this with the subject "ab".
2636
2637 16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if
2638 PCRE_CASELESS was set when matching characters that were quantified with ?
2639 or *.
2640
2641 17. A character class other than a single negated character that had a minimum
2642 but no maximum quantifier - for example [ab]{6,} - was not handled
2643 correctly by pce_dfa_exec(). It would match only one character.
2644
2645 18. A valid (though odd) pattern that looked like a POSIX character
2646 class but used an invalid character after [ (for example [[,abc,]]) caused
2647 pcre_compile() to give the error "Failed: internal error: code overflow" or
2648 in some cases to crash with a glibc free() error. This could even happen if
2649 the pattern terminated after [[ but there just happened to be a sequence of
2650 letters, a binary zero, and a closing ] in the memory that followed.
2651
2652 19. Perl's treatment of octal escapes in the range \400 to \777 has changed
2653 over the years. Originally (before any Unicode support), just the bottom 8
2654 bits were taken. Thus, for example, \500 really meant \100. Nowadays the
2655 output from "man perlunicode" includes this:
2656
2657 The regular expression compiler produces polymorphic opcodes. That
2658 is, the pattern adapts to the data and automatically switches to
2659 the Unicode character scheme when presented with Unicode data--or
2660 instead uses a traditional byte scheme when presented with byte
2661 data.
2662
2663 Sadly, a wide octal escape does not cause a switch, and in a string with
2664 no other multibyte characters, these octal escapes are treated as before.
2665 Thus, in Perl, the pattern /\500/ actually matches \100 but the pattern
2666 /\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a
2667 Unicode string.
2668
2669 I have not perpetrated such confusion in PCRE. Up till now, it took just
2670 the bottom 8 bits, as in old Perl. I have now made octal escapes with
2671 values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they
2672 translate to the appropriate multibyte character.
2673
2674 29. Applied some refactoring to reduce the number of warnings from Microsoft
2675 and Borland compilers. This has included removing the fudge introduced
2676 seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused
2677 a warning about an unused variable.
2678
2679 21. PCRE has not included VT (character 0x0b) in the set of whitespace
2680 characters since release 4.0, because Perl (from release 5.004) does not.
2681 [Or at least, is documented not to: some releases seem to be in conflict
2682 with the documentation.] However, when a pattern was studied with
2683 pcre_study() and all its branches started with \s, PCRE still included VT
2684 as a possible starting character. Of course, this did no harm; it just
2685 caused an unnecessary match attempt.
2686
2687 22. Removed a now-redundant internal flag bit that recorded the fact that case
2688 dependency changed within the pattern. This was once needed for "required
2689 byte" processing, but is no longer used. This recovers a now-scarce options
2690 bit. Also moved the least significant internal flag bit to the most-
2691 significant bit of the word, which was not previously used (hangover from
2692 the days when it was an int rather than a uint) to free up another bit for
2693 the future.
2694
2695 23. Added support for CRLF line endings as well as CR and LF. As well as the
2696 default being selectable at build time, it can now be changed at runtime
2697 via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to
2698 specify that it is scanning data with non-default line endings.
2699
2700 24. Changed the definition of CXXLINK to make it agree with the definition of
2701 LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS.
2702
2703 25. Applied Ian Taylor's patches to avoid using another stack frame for tail
2704 recursions. This makes a big different to stack usage for some patterns.
2705
2706 26. If a subpattern containing a named recursion or subroutine reference such
2707 as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of
2708 the space required for the compiled pattern went wrong and gave too small a
2709 value. Depending on the environment, this could lead to "Failed: internal
2710 error: code overflow at offset 49" or "glibc detected double free or
2711 corruption" errors.
2712
2713 27. Applied patches from Google (a) to support the new newline modes and (b) to
2714 advance over multibyte UTF-8 characters in GlobalReplace.
2715
2716 28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a
2717 difference for some implementation of PCRE in some Windows version.
2718
2719 29. Added some extra testing facilities to pcretest:
2720
2721 \q<number> in a data line sets the "match limit" value
2722 \Q<number> in a data line sets the "match recursion limt" value
2723 -S <number> sets the stack size, where <number> is in megabytes
2724
2725 The -S option isn't available for Windows.
2726
2727
2728 Version 6.6 06-Feb-06
2729 ---------------------
2730
2731 1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined
2732 in pcreposix.h. I have copied the definition from pcre.h.
2733
2734 2. Change 25 for 6.5 broke compilation in a build directory out-of-tree
2735 because pcre.h is no longer a built file.
2736
2737 3. Added Jeff Friedl's additional debugging patches to pcregrep. These are
2738 not normally included in the compiled code.
2739
2740
2741 Version 6.5 01-Feb-06
2742 ---------------------
2743
2744 1. When using the partial match feature with pcre_dfa_exec(), it was not
2745 anchoring the second and subsequent partial matches at the new starting
2746 point. This could lead to incorrect results. For example, with the pattern
2747 /1234/, partially matching against "123" and then "a4" gave a match.
2748
2749 2. Changes to pcregrep:
2750
2751 (a) All non-match returns from pcre_exec() were being treated as failures
2752 to match the line. Now, unless the error is PCRE_ERROR_NOMATCH, an
2753 error message is output. Some extra information is given for the
2754 PCRE_ERROR_MATCHLIMIT and PCRE_ERROR_RECURSIONLIMIT errors, which are
2755 probably the only errors that are likely to be caused by users (by
2756 specifying a regex that has nested indefinite repeats, for instance).
2757 If there are more than 20 of these errors, pcregrep is abandoned.
2758
2759 (b) A binary zero was treated as data while matching, but terminated the
2760 output line if it was written out. This has been fixed: binary zeroes
2761 are now no different to any other data bytes.
2762
2763 (c) Whichever of the LC_ALL or LC_CTYPE environment variables is set is
2764 used to set a locale for matching. The --locale=xxxx long option has
2765 been added (no short equivalent) to specify a locale explicitly on the
2766 pcregrep command, overriding the environment variables.
2767
2768 (d) When -B was used with -n, some line numbers in the output were one less
2769 than they should have been.
2770
2771 (e) Added the -o (--only-matching) option.
2772
2773 (f) If -A or -C was used with -c (count only), some lines of context were
2774 accidentally printed for the final match.
2775
2776 (g) Added the -H (--with-filename) option.
2777
2778 (h) The combination of options -rh failed to suppress file names for files
2779 that were found from directory arguments.
2780
2781 (i) Added the -D (--devices) and -d (--directories) options.
2782
2783 (j) Added the -F (--fixed-strings) option.
2784
2785 (k) Allow "-" to be used as a file name for -f as well as for a data file.
2786
2787 (l) Added the --colo(u)r option.
2788
2789 (m) Added Jeffrey Friedl's -S testing option, but within #ifdefs so that it
2790 is not present by default.
2791
2792 3. A nasty bug was discovered in the handling of recursive patterns, that is,
2793 items such as (?R) or (?1), when the recursion could match a number of
2794 alternatives. If it matched one of the alternatives, but subsequently,
2795 outside the recursion, there was a failure, the code tried to back up into
2796 the recursion. However, because of the way PCRE is implemented, this is not
2797 possible, and the result was an incorrect result from the match.
2798
2799 In order to prevent this happening, the specification of recursion has
2800 been changed so that all such subpatterns are automatically treated as
2801 atomic groups. Thus, for example, (?R) is treated as if it were (?>(?R)).
2802
2803 4. I had overlooked the fact that, in some locales, there are characters for
2804 which isalpha() is true but neither isupper() nor islower() are true. In
2805 the fr_FR locale, for instance, the \xAA and \xBA characters (ordmasculine
2806 and ordfeminine) are like this. This affected the treatment of \w and \W
2807 when they appeared in character classes, but not when they appeared outside
2808 a character class. The bit map for "word" characters is now created
2809 separately from the results of isalnum() instead of just taking it from the
2810 upper, lower, and digit maps. (Plus the underscore character, of course.)
2811
2812 5. The above bug also affected the handling of POSIX character classes such as
2813 [[:alpha:]] and [[:alnum:]]. These do not have their own bit maps in PCRE's
2814 permanent tables. Instead, the bit maps for such a class were previously
2815 created as the appropriate unions of the upper, lower, and digit bitmaps.
2816 Now they are created by subtraction from the [[:word:]] class, which has
2817 its own bitmap.
2818
2819 6. The [[:blank:]] character class matches horizontal, but not vertical space.
2820 It is created by subtracting the vertical space characters (\x09, \x0a,
2821 \x0b, \x0c) from the [[:space:]] bitmap. Previously, however, the
2822 subtraction was done in the overall bitmap for a character class, meaning
2823 that a class such as [\x0c[:blank:]] was incorrect because \x0c would not
2824 be recognized. This bug has been fixed.
2825
2826 7. Patches from the folks at Google:
2827
2828 (a) pcrecpp.cc: "to handle a corner case that may or may not happen in
2829 real life, but is still worth protecting against".
2830
2831 (b) pcrecpp.cc: "corrects a bug when negative radixes are used with
2832 regular expressions".
2833
2834 (c) pcre_scanner.cc: avoid use of std::count() because not all systems
2835 have it.
2836
2837 (d) Split off pcrecpparg.h from pcrecpp.h and had the former built by
2838 "configure" and the latter not, in order to fix a problem somebody had
2839 with compiling the Arg class on HP-UX.
2840
2841 (e) Improve the error-handling of the C++ wrapper a little bit.
2842
2843 (f) New tests for checking recursion limiting.
2844
2845 8. The pcre_memmove() function, which is used only if the environment does not
2846 have a standard memmove() function (and is therefore rarely compiled),
2847 contained two bugs: (a) use of int instead of size_t, and (b) it was not
2848 returning a result (though PCRE never actually uses the result).
2849
2850 9. In the POSIX regexec() interface, if nmatch is specified as a ridiculously
2851 large number - greater than INT_MAX/(3*sizeof(int)) - REG_ESPACE is
2852 returned instead of calling malloc() with an overflowing number that would
2853 most likely cause subsequent chaos.
2854
2855 10. The debugging option of pcretest was not showing the NO_AUTO_CAPTURE flag.
2856
2857 11. The POSIX flag REG_NOSUB is now supported. When a pattern that was compiled
2858 with this option is matched, the nmatch and pmatch options of regexec() are
2859 ignored.
2860
2861 12. Added REG_UTF8 to the POSIX interface. This is not defined by POSIX, but is
2862 provided in case anyone wants to the the POSIX interface with UTF-8
2863 strings.
2864
2865 13. Added CXXLDFLAGS to the Makefile parameters to provide settings only on the
2866 C++ linking (needed for some HP-UX environments).
2867
2868 14. Avoid compiler warnings in get_ucpname() when compiled without UCP support
2869 (unused parameter) and in the pcre_printint() function (omitted "default"
2870 switch label when the default is to do nothing).
2871
2872 15. Added some code to make it possible, when PCRE is compiled as a C++
2873 library, to replace subject pointers for pcre_exec() with a smart pointer
2874 class, thus making it possible to process discontinuous strings.
2875
2876 16. The two macros PCRE_EXPORT and PCRE_DATA_SCOPE are confusing, and perform
2877 much the same function. They were added by different people who were trying
2878 to make PCRE easy to compile on non-Unix systems. It has been suggested
2879 that PCRE_EXPORT be abolished now that there is more automatic apparatus
2880 for compiling on Windows systems. I have therefore replaced it with
2881 PCRE_DATA_SCOPE. This is set automatically for Windows; if not set it
2882 defaults to "extern" for C or "extern C" for C++, which works fine on
2883 Unix-like systems. It is now possible to override the value of PCRE_DATA_
2884 SCOPE with something explicit in config.h. In addition:
2885
2886 (a) pcreposix.h still had just "extern" instead of either of these macros;
2887 I have replaced it with PCRE_DATA_SCOPE.
2888
2889 (b) Functions such as _pcre_xclass(), which are internal to the library,
2890 but external in the C sense, all had PCRE_EXPORT in their definitions.
2891 This is apparently wrong for the Windows case, so I have removed it.
2892 (It makes no difference on Unix-like systems.)
2893
2894 17. Added a new limit, MATCH_LIMIT_RECURSION, which limits the depth of nesting
2895 of recursive calls to match(). This is different to MATCH_LIMIT because
2896 that limits the total number of calls to match(), not all of which increase
2897 the depth of recursion. Limiting the recursion depth limits the amount of
2898 stack (or heap if NO_RECURSE is set) that is used. The default can be set
2899 when PCRE is compiled, and changed at run time. A patch from Google adds
2900 this functionality to the C++ interface.
2901
2902 18. Changes to the handling of Unicode character properties:
2903
2904 (a) Updated the table to Unicode 4.1.0.
2905
2906 (b) Recognize characters that are not in the table as "Cn" (undefined).
2907
2908 (c) I revised the way the table is implemented to a much improved format
2909 which includes recognition of ranges. It now supports the ranges that
2910 are defined in UnicodeData.txt, and it also amalgamates other
2911 characters into ranges. This has reduced the number of entries in the
2912 table from around 16,000 to around 3,000, thus reducing its size
2913 considerably. I realized I did not need to use a tree structure after
2914 all - a binary chop search is just as efficient. Having reduced the
2915 number of entries, I extended their size from 6 bytes to 8 bytes to
2916 allow for more data.
2917
2918 (d) Added support for Unicode script names via properties such as \p{Han}.
2919
2920 19. In UTF-8 mode, a backslash followed by a non-Ascii character was not
2921 matching that character.
2922
2923 20. When matching a repeated Unicode property with a minimum greater than zero,
2924 (for example \pL{2,}), PCRE could look past the end of the subject if it
2925 reached it while seeking the minimum number of characters. This could
2926 happen only if some of the characters were more than one byte long, because
2927 there is a check for at least the minimum number of bytes.
2928
2929 21. Refactored the implementation of \p and \P so as to be more general, to
2930 allow for more different types of property in future. This has changed the
2931 compiled form incompatibly. Anybody with saved compiled patterns that use
2932 \p or \P will have to recompile them.
2933
2934 22. Added "Any" and "L&" to the supported property types.
2935
2936 23. Recognize \x{...} as a code point specifier, even when not in UTF-8 mode,
2937 but give a compile time error if the value is greater than 0xff.
2938
2939 24. The man pages for pcrepartial, pcreprecompile, and pcre_compile2 were
2940 accidentally not being installed or uninstalled.
2941
2942 25. The pcre.h file was built from pcre.h.in, but the only changes that were
2943 made were to insert the current release number. This seemed silly, because
2944 it made things harder for people building PCRE on systems that don't run
2945 "configure". I have turned pcre.h into a distributed file, no longer built
2946 by "configure", with the version identification directly included. There is
2947 no longer a pcre.h.in file.
2948
2949 However, this change necessitated a change to the pcre-config script as
2950 well. It is built from pcre-config.in, and one of the substitutions was the
2951 release number. I have updated configure.ac so that ./configure now finds
2952 the release number by grepping pcre.h.
2953
2954 26. Added the ability to run the tests under valgrind.
2955
2956
2957 Version 6.4 05-Sep-05
2958 ---------------------
2959
2960 1. Change 6.0/10/(l) to pcregrep introduced a bug that caused separator lines
2961 "--" to be printed when multiple files were scanned, even when none of the
2962 -A, -B, or -C options were used. This is not compatible with Gnu grep, so I
2963 consider it to be a bug, and have restored the previous behaviour.
2964
2965 2. A couple of code tidies to get rid of compiler warnings.
2966
2967 3. The pcretest program used to cheat by referring to symbols in the library
2968 whose names begin with _pcre_. These are internal symbols that are not
2969 really supposed to be visible externally, and in some environments it is
2970 possible to suppress them. The cheating is now confined to including
2971 certain files from the library's source, which is a bit cleaner.
2972
2973 4. Renamed pcre.in as pcre.h.in to go with pcrecpp.h.in; it also makes the
2974 file's purpose clearer.
2975
2976 5. Reorganized pcre_ucp_findchar().
2977
2978
2979 Version 6.3 15-Aug-05
2980 ---------------------
2981
2982 1. The file libpcre.pc.in did not have general read permission in the tarball.
2983
2984 2. There were some problems when building without C++ support:
2985
2986 (a) If C++ support was not built, "make install" and "make test" still
2987 tried to test it.
2988
2989 (b) There were problems when the value of CXX was explicitly set. Some
2990 changes have been made to try to fix these, and ...
2991
2992 (c) --disable-cpp can now be used to explicitly disable C++ support.
2993
2994 (d) The use of @CPP_OBJ@ directly caused a blank line preceded by a
2995 backslash in a target when C++ was disabled. This confuses some
2996 versions of "make", apparently. Using an intermediate variable solves
2997 this. (Same for CPP_LOBJ.)
2998
2999 3. $(LINK_FOR_BUILD) now includes $(CFLAGS_FOR_BUILD) and $(LINK)
3000 (non-Windows) now includes $(CFLAGS) because these flags are sometimes
3001 necessary on certain architectures.
3002
3003 4. Added a setting of -export-symbols-regex to the link command to remove
3004 those symbols that are exported in the C sense, but actually are local
3005 within the library, and not documented. Their names all begin with
3006 "_pcre_". This is not a perfect job, because (a) we have to except some
3007 symbols that pcretest ("illegally") uses, and (b) the facility isn't always
3008 available (and never for static libraries). I have made a note to try to
3009 find a way round (a) in the future.
3010
3011
3012 Version 6.2 01-Aug-05
3013 ---------------------
3014
3015 1. There was no test for integer overflow of quantifier values. A construction
3016 such as {1111111111111111} would give undefined results. What is worse, if
3017 a minimum quantifier for a parenthesized subpattern overflowed and became
3018 negative, the calculation of the memory size went wrong. This could have
3019 led to memory overwriting.
3020
3021 2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
3022
3023 3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
3024 operating environments where this matters.
3025
3026 4. Applied Giuseppe Maxia's patch to add additional features for controlling
3027 PCRE options from within the C++ wrapper.
3028
3029 5. Named capturing subpatterns were not being correctly counted when a pattern
3030 was compiled. This caused two problems: (a) If there were more than 100
3031 such subpatterns, the calculation of the memory needed for the whole
3032 compiled pattern went wrong, leading to an overflow error. (b) Numerical
3033 back references of the form \12, where the number was greater than 9, were
3034 not recognized as back references, even though there were sufficient
3035 previous subpatterns.
3036
3037 6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
3038 versions of gcc, e.g. 2.95.4.
3039
3040
3041 Version 6.1 21-Jun-05
3042 ---------------------
3043
3044 1. There was one reference to the variable "posix" in pcretest.c that was not
3045 surrounded by "#if !defined NOPOSIX".
3046
3047 2. Make it possible to compile pcretest without DFA support, UTF8 support, or
3048 the cross-check on the old pcre_info() function, for the benefit of the
3049 cut-down version of PCRE that is currently imported into Exim.
3050
3051 3. A (silly) pattern starting with (?i)(?-i) caused an internal space
3052 allocation error. I've done the easy fix, which wastes 2 bytes for sensible
3053 patterns that start (?i) but I don't think that matters. The use of (?i) is
3054 just an example; this all applies to the other options as well.
3055
3056 4. Since libtool seems to echo the compile commands it is issuing, the output
3057 from "make" can be reduced a bit by putting "@" in front of each libtool
3058 compile command.
3059
3060 5. Patch from the folks at Google for configure.in to be a bit more thorough
3061 in checking for a suitable C++ installation before trying to compile the
3062 C++ stuff. This should fix a reported problem when a compiler was present,
3063 but no suitable headers.
3064
3065 6. The man pages all had just "PCRE" as their title. I have changed them to
3066 be the relevant file name. I have also arranged that these names are
3067 retained in the file doc/pcre.txt, which is a concatenation in text format
3068 of all the man pages except the little individual ones for each function.
3069
3070 7. The NON-UNIX-USE file had not been updated for the different set of source
3071 files that come with release 6. I also added a few comments about the C++
3072 wrapper.
3073
3074
3075 Version 6.0 07-Jun-05
3076 ---------------------
3077
3078 1. Some minor internal re-organization to help with my DFA experiments.
3079
3080 2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
3081 didn't matter for the library itself when fully configured, but did matter
3082 when compiling without UCP support, or within Exim, where the ucp files are
3083 not imported.
3084
3085 3. Refactoring of the library code to split up the various functions into
3086 different source modules. The addition of the new DFA matching code (see
3087 below) to a single monolithic source would have made it really too
3088 unwieldy, quite apart from causing all the code to be include in a
3089 statically linked application, when only some functions are used. This is
3090 relevant even without the DFA addition now that patterns can be compiled in
3091 one application and matched in another.
3092
3093 The downside of splitting up is that there have to be some external
3094 functions and data tables that are used internally in different modules of
3095 the library but which are not part of the API. These have all had their
3096 names changed to start with "_pcre_" so that they are unlikely to clash
3097 with other external names.
3098
3099 4. Added an alternate matching function, pcre_dfa_exec(), which matches using
3100 a different (DFA) algorithm. Although it is slower than the original
3101 function, it does have some advantages for certain types of matching
3102 problem.
3103
3104 5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
3105 including restarting after a partial match.
3106
3107 6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
3108 defined when compiling for Windows was sent to me. I have put it into the
3109 code, though I have no means of testing or verifying it.
3110
3111 7. Added the pcre_refcount() auxiliary function.
3112
3113 8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
3114 match before or at the first newline in the subject string. In pcretest,
3115 the /f option on a pattern can be used to set this.
3116
3117 9. A repeated \w when used in UTF-8 mode with characters greater than 256
3118 would behave wrongly. This has been present in PCRE since release 4.0.
3119
3120 10. A number of changes to the pcregrep command:
3121
3122 (a) Refactored how -x works; insert ^(...)$ instead of setting
3123 PCRE_ANCHORED and checking the length, in preparation for adding
3124 something similar for -w.
3125
3126 (b) Added the -w (match as a word) option.
3127
3128 (c) Refactored the way lines are read and buffered so as to have more
3129 than one at a time available.
3130
3131 (d) Implemented a pcregrep test script.
3132
3133 (e) Added the -M (multiline match) option. This allows patterns to match
3134 over several lines of the subject. The buffering ensures that at least
3135 8K, or the rest of the document (whichever is the shorter) is available
3136 for matching (and similarly the previous 8K for lookbehind assertions).
3137
3138 (f) Changed the --help output so that it now says
3139
3140 -w, --word-regex(p)
3141
3142 instead of two lines, one with "regex" and the other with "regexp"
3143 because that confused at least one person since the short forms are the
3144 same. (This required a bit of code, as the output is generated
3145 automatically from a table. It wasn't just a text change.)
3146
3147 (g) -- can be used to terminate pcregrep options if the next thing isn't an
3148 option but starts with a hyphen. Could be a pattern or a path name
3149 starting with a hyphen, for instance.
3150
3151 (h) "-" can be given as a file name to represent stdin.
3152
3153 (i) When file names are being printed, "(standard input)" is used for
3154 the standard input, for compatibility with GNU grep. Previously
3155 "<stdin>" was used.
3156
3157 (j) The option --label=xxx can be used to supply a name to be used for
3158 stdin when file names are being printed. There is no short form.
3159
3160 (k) Re-factored the options decoding logic because we are going to add
3161 two more options that take data. Such options can now be given in four
3162 different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
3163
3164 (l) Added the -A, -B, and -C options for requesting that lines of context
3165 around matches be printed.
3166
3167 (m) Added the -L option to print the names of files that do not contain
3168 any matching lines, that is, the complement of -l.
3169
3170 (n) The return code is 2 if any file cannot be opened, but pcregrep does
3171 continue to scan other files.
3172
3173 (o) The -s option was incorrectly implemented. For compatibility with other
3174 greps, it now suppresses the error message for a non-existent or non-
3175 accessible file (but not the return code). There is a new option called
3176 -q that suppresses the output of matching lines, which was what -s was
3177 previously doing.
3178
3179 (p) Added --include and --exclude options to specify files for inclusion
3180 and exclusion when recursing.
3181
3182 11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
3183 Hopefully, it now does.
3184
3185 12. Missing cast in pcre_study().
3186
3187 13. Added an "uninstall" target to the makefile.
3188
3189 14. Replaced "extern" in the function prototypes in Makefile.in with
3190 "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
3191 world, but is set differently for Windows.
3192
3193 15. Added a second compiling function called pcre_compile2(). The only
3194 difference is that it has an extra argument, which is a pointer to an
3195 integer error code. When there is a compile-time failure, this is set
3196 non-zero, in addition to the error test pointer being set to point to an
3197 error message. The new argument may be NULL if no error number is required
3198 (but then you may as well call pcre_compile(), which is now just a
3199 wrapper). This facility is provided because some applications need a
3200 numeric error indication, but it has also enabled me to tidy up the way
3201 compile-time errors are handled in the POSIX wrapper.
3202
3203 16. Added VPATH=.libs to the makefile; this should help when building with one
3204 prefix path and installing with another. (Or so I'm told by someone who
3205 knows more about this stuff than I do.)
3206
3207 17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
3208 passes PCRE_DOTALL to the pcre_compile() function, making the "." character
3209 match everything, including newlines. This is not POSIX-compatible, but
3210 somebody wanted the feature. From pcretest it can be activated by using
3211 both the P and the s flags.
3212
3213 18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
3214
3215 19. libpcre.pc was being incorrectly installed as executable.
3216
3217 20. A couple of places in pcretest check for end-of-line by looking for '\n';
3218 it now also looks for '\r' so that it will work unmodified on Windows.
3219
3220 21. Added Google's contributed C++ wrapper to the distribution.
3221
3222 22. Added some untidy missing memory free() calls in pcretest, to keep
3223 Electric Fence happy when testing.
3224
3225
3226
3227 Version 5.0 13-Sep-04
3228 ---------------------
3229
3230 1. Internal change: literal characters are no longer packed up into items
3231 containing multiple characters in a single byte-string. Each character
3232 is now matched using a separate opcode. However, there may be more than one
3233 byte in the character in UTF-8 mode.
3234
3235 2. The pcre_callout_block structure has two new fields: pattern_position and
3236 next_item_length. These contain the offset in the pattern to the next match
3237 item, and its length, respectively.
3238
3239 3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
3240 insertion of callouts before each pattern item. Added the /C option to
3241 pcretest to make use of this.
3242
3243 4. On the advice of a Windows user, the lines
3244
3245 #if defined(_WIN32) || defined(WIN32)
3246 _setmode( _fileno( stdout ), 0x8000 );
3247 #endif /* defined(_WIN32) || defined(WIN32) */
3248
3249 have been added to the source of pcretest. This apparently does useful
3250 magic in relation to line terminators.
3251
3252 5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
3253 for the benefit of those environments where the "b" makes a difference.
3254
3255 6. The icc compiler has the same options as gcc, but "configure" doesn't seem
3256 to know about it. I have put a hack into configure.in that adds in code
3257 to set GCC=yes if CC=icc. This seems to end up at a point in the
3258 generated configure script that is early enough to affect the setting of
3259 compiler options, which is what is needed, but I have no means of testing
3260 whether it really works. (The user who reported this had patched the
3261 generated configure script, which of course I cannot do.)
3262
3263 LATER: After change 22 below (new libtool files), the configure script
3264 seems to know about icc (and also ecc). Therefore, I have commented out
3265 this hack in configure.in.
3266
3267 7. Added support for pkg-config (2 patches were sent in).
3268
3269 8. Negated POSIX character classes that used a combination of internal tables
3270 were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
3271 [[:^ascii]]. Typically, they would match almost any characters. The other
3272 POSIX classes were not broken in this way.
3273
3274 9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
3275 to find the match, as PCRE was deluded into thinking that the match had to
3276 start at the start point or following a newline. The same bug applied to
3277 patterns with negative forward assertions or any backward assertions
3278 preceding ".*" at the start, unless the pattern required a fixed first
3279 character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
3280
3281 10. In UTF-8 mode, when moving forwards in the subject after a failed match
3282 starting at the last subject character, bytes beyond the end of the subject
3283 string were read.
3284
3285 11. Renamed the variable "class" as "classbits" to make life easier for C++
3286 users. (Previously there was a macro definition, but it apparently wasn't
3287 enough.)
3288
3289 12. Added the new field "tables" to the extra data so that tables can be passed
3290 in at exec time, or the internal tables can be re-selected. This allows
3291 a compiled regex to be saved and re-used at a later time by a different
3292 program that might have everything at different addresses.
3293
3294 13. Modified the pcre-config script so that, when run on Solaris, it shows a
3295 -R library as well as a -L library.
3296
3297 14. The debugging options of pcretest (-d on the command line or D on a
3298 pattern) showed incorrect output for anything following an extended class
3299 that contained multibyte characters and which was followed by a quantifier.
3300
3301 15. Added optional support for general category Unicode character properties
3302 via the \p, \P, and \X escapes. Unicode property support implies UTF-8
3303 support. It adds about 90K to the size of the library. The meanings of the
3304 inbuilt class escapes such as \d and \s have NOT been changed.
3305
3306 16. Updated pcredemo.c to include calls to free() to release the memory for the
3307 compiled pattern.
3308
3309 17. The generated file chartables.c was being created in the source directory
3310 instead of in the building directory. This caused the build to fail if the
3311 source directory was different from the building directory, and was
3312 read-only.
3313
3314 18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
3315 file. No doubt somebody will tell me if they don't make sense... Also added
3316 Dan Mooney's comments about building on OpenVMS.
3317
3318 19. Added support for partial matching via the PCRE_PARTIAL option for
3319 pcre_exec() and the \P data escape in pcretest.
3320
3321 20. Extended pcretest with 3 new pattern features:
3322
3323 (i) A pattern option of the form ">rest-of-line" causes pcretest to
3324 write the compiled pattern to the file whose name is "rest-of-line".
3325 This is a straight binary dump of the data, with the saved pointer to
3326 the character tables forced to be NULL. The study data, if any, is
3327 written too. After writing, pcretest reads a new pattern.
3328
3329 (ii) If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
3330 compiled pattern from the given file. There must not be any
3331 occurrences of "<" in the file name (pretty unlikely); if there are,
3332 pcretest will instead treat the initial "<" as a pattern delimiter.
3333 After reading in the pattern, pcretest goes on to read data lines as
3334 usual.
3335
3336 (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
3337 and 16-bit fields in a compiled pattern, to simulate a pattern that
3338 was compiled on a host of opposite endianness.
3339
3340 21. The pcre-exec() function can now cope with patterns that were compiled on
3341 hosts of opposite endianness, with this restriction:
3342
3343 As for any compiled expression that is saved and used later, the tables
3344 pointer field cannot be preserved; the extra_data field in the arguments
3345 to pcre_exec() should be used to pass in a tables address if a value
3346 other than the default internal tables were used at compile time.
3347
3348 22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
3349 now diagnosed as an error. Previously, most of the time, a negative number
3350 would have been treated as zero, but if in addition "ovector" was passed as
3351 NULL, a crash could occur.
3352
3353 23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
3354 new versions from the libtool 1.5 distribution (the last one is a copy of
3355 a file called libtool.m4). This seems to have fixed the need to patch
3356 "configure" to support Darwin 1.3 (which I used to do). However, I still
3357 had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
3358 workstation).
3359
3360 24. Changed the PCRE licence to be the more standard "BSD" licence.
3361
3362
3363 Version 4.5 01-Dec-03
3364 ---------------------
3365
3366 1. There has been some re-arrangement of the code for the match() function so
3367 that it can be compiled in a version that does not call itself recursively.
3368 Instead, it keeps those local variables that need separate instances for
3369 each "recursion" in a frame on the heap, and gets/frees frames whenever it
3370 needs to "recurse". Keeping track of where control must go is done by means
3371 of setjmp/longjmp. The whole thing is implemented by a set of macros that
3372 hide most of the details from the main code, and operates only if
3373 NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
3374 "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
3375 operating.
3376
3377 To make it easier for callers to provide specially tailored get/free
3378 functions for this usage, two new functions, pcre_stack_malloc, and
3379 pcre_stack_free, are used. They are always called in strict stacking order,
3380 and the size of block requested is always the same.
3381
3382 The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
3383 PCRE has been compiled to use the stack or the heap for recursion. The
3384 -C option of pcretest uses this to show which version is compiled.
3385
3386 A new data escape \S, is added to pcretest; it causes the amounts of store
3387 obtained and freed by both kinds of malloc/free at match time to be added
3388 to the output.
3389
3390 2. Changed the locale test to use "fr_FR" instead of "fr" because that's
3391 what's available on my current Linux desktop machine.
3392
3393 3. When matching a UTF-8 string, the test for a valid string at the start has
3394 been extended. If start_offset is not zero, PCRE now checks that it points
3395 to a byte that is the start of a UTF-8 character. If not, it returns
3396 PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
3397 this is necessary because there may be backward assertions in the pattern.
3398 When matching the same subject several times, it may save resources to use
3399 PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
3400
3401 4. The code for checking the validity of UTF-8 strings has been tightened so
3402 that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
3403 containing "overlong sequences".
3404
3405 5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
3406 I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
3407 should have been "&", but it just so happened that all the cases this let
3408 through by mistake were picked up later in the function.
3409
3410 6. I had used a variable called "isblank" - this is a C99 function, causing
3411 some compilers to warn. To avoid this, I renamed it (as "blankclass").
3412
3413 7. Cosmetic: (a) only output another newline at the end of pcretest if it is
3414 prompting; (b) run "./pcretest /dev/null" at the start of the test script
3415 so the version is shown; (c) stop "make test" echoing "./RunTest".
3416
3417 8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
3418
3419 9. The prototype for memmove() for systems that don't have it was using
3420 size_t, but the inclusion of the header that defines size_t was later. I've
3421 moved the #includes for the C headers earlier to avoid this.
3422
3423 10. Added some adjustments to the code to make it easier to compiler on certain
3424 special systems:
3425
3426 (a) Some "const" qualifiers were missing.
3427 (b) Added the macro EXPORT before all exported functions; by default this
3428 is defined to be empty.
3429 (c) Changed the dftables auxiliary program (that builds chartables.c) so
3430 that it reads its output file name as an argument instead of writing
3431 to the standard output and assuming this can be redirected.
3432
3433 11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
3434 class containing characters with values greater than 255, PCRE compilation
3435 went into a loop.
3436
3437 12. A recursive reference to a subpattern that was within another subpattern
3438 that had a minimum quantifier of zero caused PCRE to crash. For example,
3439 (x(y(?2))z)? provoked this bug with a subject that got as far as the
3440 recursion. If the recursively-called subpattern itself had a zero repeat,
3441 that was OK.
3442
3443 13. In pcretest, the buffer for reading a data line was set at 30K, but the
3444 buffer into which it was copied (for escape processing) was still set at
3445 1024, so long lines caused crashes.
3446
3447 14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
3448 "internal error: code overflow...". This applied to any character class
3449 that was followed by a possessive quantifier.
3450
3451 15. Modified the Makefile to add libpcre.la as a prerequisite for
3452 libpcreposix.la because I was told this is needed for a parallel build to
3453 work.
3454
3455 16. If a pattern that contained .* following optional items at the start was
3456 studied, the wrong optimizing data was generated, leading to matching
3457 errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
3458 matching string must start with a or b or c. The correct conclusion for
3459 this pattern is that a match can start with any character.
3460
3461
3462 Version 4.4 13-Aug-03
3463 ---------------------
3464
3465 1. In UTF-8 mode, a character class containing characters with values between
3466 127 and 255 was not handled correctly if the compiled pattern was studied.
3467 In fixing this, I have also improved the studying algorithm for such
3468 classes (slightly).
3469
3470 2. Three internal functions had redundant arguments passed to them. Removal
3471 might give a very teeny performance improvement.
3472
3473 3. Documentation bug: the value of the capture_top field in a callout is *one
3474 more than* the number of the hightest numbered captured substring.
3475
3476 4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
3477 in incorrectly linking with a previously installed version. They now link
3478 explicitly with libpcre.la.
3479
3480 5. configure.in no longer needs to recognize Cygwin specially.
3481
3482 6. A problem in pcre.in for Windows platforms is fixed.
3483
3484 7. If a pattern was successfully studied, and the -d (or /D) flag was given to
3485 pcretest, it used to include the size of the study block as part of its
3486 output. Unfortunately, the structure contains a field that has a different
3487 size on different hardware architectures. This meant that the tests that
3488 showed this size failed. As the block is currently always of a fixed size,
3489 this information isn't actually particularly useful in pcretest output, so
3490 I have just removed it.
3491
3492 8. Three pre-processor statements accidentally did not start in column 1.
3493 Sadly, there are *still* compilers around that complain, even though
3494 standard C has not required this for well over a decade. Sigh.
3495
3496 9. In pcretest, the code for checking callouts passed small integers in the
3497 callout_data field, which is a void * field. However, some picky compilers
3498 complained about the casts involved for this on 64-bit systems. Now
3499 pcretest passes the address of the small integer instead, which should get
3500 rid of the warnings.
3501
3502 10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
3503 both compile and run time, and gives an error if an invalid UTF-8 sequence
3504 is found. There is a option for disabling this check in cases where the
3505 string is known to be correct and/or the maximum performance is wanted.
3506
3507 11. In response to a bug report, I changed one line in Makefile.in from
3508
3509 -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
3510 to
3511 -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
3512
3513 to look similar to other lines, but I have no way of telling whether this
3514 is the right thing to do, as I do not use Windows. No doubt I'll get told
3515 if it's wrong...
3516
3517
3518 Version 4.3 21-May-03
3519 ---------------------
3520
3521 1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
3522 Makefile.
3523
3524 2. Some refactoring to improve the quality of the code:
3525
3526 (i) The utf8_table... variables are now declared "const".
3527
3528 (ii) The code for \cx, which used the "case flipping" table to upper case
3529 lower case letters, now just substracts 32. This is ASCII-specific,
3530 but the whole concept of \cx is ASCII-specific, so it seems
3531 reasonable.
3532
3533 (iii) PCRE was using its character types table to recognize decimal and
3534 hexadecimal digits in the pattern. This is silly, because it handles
3535 only 0-9, a-f, and A-F, but the character types table is locale-
3536 specific, which means strange things might happen. A private
3537 table is now used for this - though it costs 256 bytes, a table is
3538 much faster than multiple explicit tests. Of course, the standard
3539 character types table is still used for matching digits in subject
3540 strings against \d.
3541
3542 (iv) Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
3543 ending in _t are). So I've renamed it as ESC_tee.
3544
3545 3. The first argument for regexec() in the POSIX wrapper should have been
3546 defined as "const".
3547
3548 4. Changed pcretest to use malloc() for its buffers so that they can be
3549 Electric Fenced for debugging.
3550
3551 5. There were several places in the code where, in UTF-8 mode, PCRE would try
3552 to read one or more bytes before the start of the subject string. Often this
3553 had no effect on PCRE's behaviour, but in some circumstances it could
3554 provoke a segmentation fault.
3555
3556 6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
3557 to try to read one or more bytes before the start of the subject string.
3558
3559 7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
3560 UTF-8 support could misbehave in various ways if the subject string
3561 contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
3562 area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
3563 back over UTF-8 characters.)
3564
3565
3566 Version 4.2 14-Apr-03
3567 ---------------------
3568
3569 1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.
3570
3571 2. Changes to the building process, supplied by Ronald Landheer-Cieslak
3572 [ON_WINDOWS]: new variable, "#" on non-Windows platforms
3573 [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
3574 [WIN_PREFIX]: new variable, "cyg" for Cygwin
3575 * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
3576 and BUILD_EXEEXT
3577 Note: automatic setting of the BUILD variables is not yet working
3578 set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
3579 compile-time but not at link-time
3580 [LINK]: use for linking executables only
3581 make different versions for Windows and non-Windows
3582 [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
3583 libraries
3584 [LINK_FOR_BUILD]: new variable
3585 [OBJEXT]: use throughout
3586 [EXEEXT]: use throughout
3587 <winshared>: new target
3588 <wininstall>: new target
3589 <dftables.o>: use native compiler
3590 <dftables>: use native linker
3591 <install>: handle Windows platform correctly
3592 <clean>: ditto
3593 <check>: ditto
3594 copy DLL to top builddir before testing
3595
3596 As part of these changes, -no-undefined was removed again. This was reported
3597 to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
3598 in any case.
3599
3600 3. Some tidies to get rid of compiler warnings:
3601
3602 . In the match_data structure, match_limit was an unsigned long int, whereas
3603 match_call_count was an int. I've made them both unsigned long ints.
3604
3605 . In pcretest the fact that a const uschar * doesn't automatically cast to
3606 a void * provoked a warning.
3607
3608 . Turning on some more compiler warnings threw up some "shadow" variables
3609 and a few more missing casts.
3610
3611 4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
3612 option, a class that contained a single character with a value between 128
3613 and 255 (e.g. /[\xFF]/) caused PCRE to crash.
3614
3615 5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
3616 option, a class that contained several characters, but with at least one
3617 whose value was between 128 and 255 caused PCRE to crash.
3618
3619
3620 Version 4.1 12-Mar-03
3621 ---------------------
3622
3623 1. Compiling with gcc -pedantic found a couple of places where casts were
3624 needed, and a string in dftables.c that was longer than standard compilers are
3625 required to support.
3626
3627 2. Compiling with Sun's compiler found a few more places where the code could
3628 be tidied up in order to avoid warnings.
3629
3630 3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
3631 first of these names is deprecated in the latest Autoconf in favour of the name
3632 CC_FOR_BUILD, because "host" is typically used to mean the system on which the
3633 compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
3634 analogy I have changed it to CFLAGS_FOR_BUILD.
3635
3636 4. Added -no-undefined to the linking command in the Makefile, because this is
3637 apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
3638 linking step for the pcreposix library.
3639
3640 5. PCRE was failing to diagnose the case of two named groups with the same
3641 name.
3642
3643 6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
3644 literal character that is needed in the subject for a match, and scans along to
3645 ensure that it is present before embarking on the full matching process. This
3646 saves time in cases of nested unlimited repeats that are never going to match.
3647 Problem: the scan can take a lot of time if the subject is very long (e.g.
3648 megabytes), thus penalizing straightforward matches. It is now done only if the
3649 amount of subject to be scanned is less than 1000 bytes.
3650
3651 7. A lesser problem with the same optimization is that it was recording the
3652 first character of an anchored pattern as "needed", thus provoking a search
3653 right along the subject, even when the first match of the pattern was going to
3654 fail. The "needed" character is now not set for anchored patterns, unless it
3655 follows something in the pattern that is of non-fixed length. Thus, it still
3656 fulfils its original purpose of finding quick non-matches in cases of nested
3657 unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.
3658
3659
3660 Version 4.0 17-Feb-03
3661 ---------------------
3662
3663 1. If a comment in an extended regex that started immediately after a meta-item
3664 extended to the end of string, PCRE compiled incorrect data. This could lead to
3665 all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.
3666
3667 2. Moved to autoconf 2.53 and libtool 1.4.2.
3668
3669 3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
3670 the special perltest8 script is no longer needed - all the tests can be run
3671 from a single perltest script.
3672
3673 4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
3674 by \s. It has now been removed in PCRE. This means it isn't recognized as
3675 whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
3676 class [:space:] *does* include VT, thereby creating a mess.
3677
3678 5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
3679 space and tab.
3680
3681 6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
3682 its new features into the main test script, reducing the number of scripts.
3683
3684 7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
3685 were backward compatible, and made the (?i) apply to the whole pattern, as if
3686 /i were given. Now it behaves more logically, and applies the option setting
3687 only to what follows. PCRE has been changed to follow suit. However, if it
3688 finds options settings right at the start of the pattern, it extracts them into
3689 the global options, as before. Thus, they show up in the info data.
3690
3691 8. Added support for the \Q...\E escape sequence. Characters in between are
3692 treated as literals. This is slightly different from Perl in that $ and @ are
3693 also handled as literals inside the quotes. In Perl, they will cause variable
3694 interpolation. Note the following examples:
3695
3696 Pattern PCRE matches Perl matches
3697
3698 \Qabc$xyz\E abc$xyz abc followed by the contents of $xyz
3699 \Qabc\$xyz\E abc\$xyz abc\$xyz
3700 \Qabc\E\$\Qxyz\E abc$xyz abc$xyz
3701
3702 For compatibility with Perl, \Q...\E sequences are recognized inside character
3703 classes as well as outside them.
3704
3705 9. Re-organized 3 code statements in pcretest to avoid "overflow in
3706 floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
3707 (size_t) cast to one statement in pcretest and one in pcreposix to avoid
3708 signed/unsigned warnings.
3709
3710 10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
3711 option for pcretest, so I've replaced it by a simple function that does just
3712 that job.
3713
3714 11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
3715 "pcregrep -".
3716
3717 12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
3718 Java package. This provides some syntactic sugar for simple cases of what my
3719 documentation calls "once-only subpatterns". A pattern such as x*+ is the same
3720 as (?>x*). In other words, if what is inside (?>...) is just a single repeated
3721 item, you can use this simplified notation. Note that only makes sense with
3722 greedy quantifiers. Consequently, the use of the possessive quantifier forces
3723 greediness, whatever the setting of the PCRE_UNGREEDY option.
3724
3725 13. A change of greediness default within a pattern was not taking effect at
3726 the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
3727 subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
3728 was abstracted outside.
3729
3730 14. PCRE now supports the \G assertion. It is true when the current matching
3731 position is at the start point of the match. This differs from \A when the
3732 starting offset is non-zero. Used with the /g option of pcretest (or similar
3733 code), it works in the same way as it does for Perl's /g option. If all
3734 alternatives of a regex begin with \G, the expression is anchored to the start
3735 match position, and the "anchored" flag is set in the compiled expression.
3736
3737 15. Some bugs concerning the handling of certain option changes within patterns
3738 have been fixed. These applied to options other than (?ims). For example,
3739 "a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
3740 been the other way round. Some of this was related to change 7 above.
3741
3742 16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
3743 features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
3744 and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
3745 POSIX classes only within a class (e.g. /[[:alpha:]]/).
3746
3747 17. Added support for Perl's \C escape. This matches one byte, even in UTF8
3748 mode. Unlike ".", it always matches newline, whatever the setting of
3749 PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
3750 assertions. Perl allows it, but it doesn't (in general) work because it can't
3751 calculate the length of the lookbehind. At least, that's the case for Perl
3752 5.8.0 - I've been told they are going to document that it doesn't work in
3753 future.
3754
3755 18. Added an error diagnosis for escapes that PCRE does not support: these are
3756 \L, \l, \N, \P, \p, \U, \u, and \X.
3757
3758 19. Although correctly diagnosing a missing ']' in a character class, PCRE was
3759 reading past the end of the pattern in cases such as /[abcd/.
3760
3761 20. PCRE was getting more memory than necessary for patterns with classes that
3762 contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.
3763
3764 21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
3765 compiling PCRE for use with Virtual Pascal.
3766
3767 22. Small fix to the Makefile to make it work properly if the build is done
3768 outside the source tree.
3769
3770 23. Added a new extension: a condition to go with recursion. If a conditional
3771 subpattern starts with (?(R) the "true" branch is used if recursion has
3772 happened, whereas the "false" branch is used only at the top level.
3773
3774 24. When there was a very long string of literal characters (over 255 bytes
3775 without UTF support, over 250 bytes with UTF support), the computation of how
3776 much memory was required could be incorrect, leading to segfaults or other
3777 strange effects.
3778
3779 25. PCRE was incorrectly assuming anchoring (either to start of subject or to
3780 start of line for a non-DOTALL pattern) when a pattern started with (.*) and
3781 there was a subsequent back reference to those brackets. This meant that, for
3782 example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
3783 possible to check for precisely this case. All we can do is abandon the
3784 optimization if .* occurs inside capturing brackets when there are any back
3785 references whatsoever. (See below for a better fix that came later.)
3786
3787 26. The handling of the optimization for finding the first character of a
3788 non-anchored pattern, and for finding a character that is required later in the
3789 match were failing in some cases. This didn't break the matching; it just
3790 failed to optimize when it could. The way this is done has been re-implemented.
3791
3792 27. Fixed typo in error message for invalid (?R item (it said "(?p").
3793
3794 28. Added a new feature that provides some of the functionality that Perl
3795 provides with (?{...}). The facility is termed a "callout". The way it is done
3796 in PCRE is for the caller to provide an optional function, by setting
3797 pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
3798 global variable. By default it is unset, which disables all calling out. To get
3799 the function called, the regex must include (?C) at appropriate points. This
3800 is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
3801 This provides a means of identifying different callout points. When PCRE
3802 reaches such a point in the regex, if pcre_callout has been set, the external
3803 function is called. It is provided with data in a structure called
3804 pcre_callout_block, which is defined in pcre.h. If the function returns 0,
3805 matching continues; if it returns a non-zero value, the match at the current
3806 point fails. However, backtracking will occur if possible. [This was changed
3807 later and other features added - see item 49 below.]
3808
3809 29. pcretest is upgraded to test the callout functionality. It provides a
3810 callout function that displays information. By default, it shows the start of
3811 the match and the current position in the text. There are some new data escapes
3812 to vary what happens:
3813
3814 \C+ in addition, show current contents of captured substrings
3815 \C- do not supply a callout function
3816 \C!n return 1 when callout number n is reached
3817 \C!n!m return 1 when callout number n is reached for the mth time
3818
3819 30. If pcregrep was called with the -l option and just a single file name, it
3820 output "<stdin>" if a match was found, instead of the file name.
3821
3822 31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
3823 slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
3824 pcre_exec(). This saves a malloc/free per call. The default value of
3825 POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
3826 when configuring.
3827
3828 32. The default maximum size of a compiled pattern is 64K. There have been a
3829 few cases of people hitting this limit. The code now uses macros to handle the
3830 storing of links as offsets within the compiled pattern. It defaults to 2-byte
3831 links, but this can be changed to 3 or 4 bytes by --with-link-size when
3832 configuring. Tests 2 and 5 work only with 2-byte links because they output
3833 debugging information about compiled patterns.
3834
3835 33. Internal code re-arrangements:
3836
3837 (a) Moved the debugging function for printing out a compiled regex into
3838 its own source file (printint.c) and used #include to pull it into
3839 pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
3840 separate copies.
3841
3842 (b) Defined the list of op-code names for debugging as a macro in
3843 internal.h so that it is next to the definition of the opcodes.
3844
3845 (c) Defined a table of op-code lengths for simpler skipping along compiled
3846 code. This is again a macro in internal.h so that it is next to the
3847 definition of the opcodes.
3848
3849 34. Added support for recursive calls to individual subpatterns, along the
3850 lines of Robin Houston's patch (but implemented somewhat differently).
3851
3852 35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
3853 allow it to read and process whole directories in Win32. This code was
3854 contributed by Lionel Fourquaux; it has not been tested by me.
3855
3856 36. Added support for named subpatterns. The Python syntax (?P<name>...) is
3857 used to name a group. Names consist of alphanumerics and underscores, and must
3858 be unique. Back references use the syntax (?P=name) and recursive calls use
3859 (?P>name) which is a PCRE extension to the Python extension. Groups still have
3860 numbers. The function pcre_fullinfo() can be used after compilation to extract
3861 a name/number map. There are three relevant calls:
3862
3863 PCRE_INFO_NAMEENTRYSIZE yields the size of each entry in the map
3864 PCRE_INFO_NAMECOUNT yields the number of entries
3865 PCRE_INFO_NAMETABLE yields a pointer to the map.
3866
3867 The map is a vector of fixed-size entries. The size of each entry depends on
3868 the length of the longest name used. The first two bytes of each entry are the
3869 group number, most significant byte first. There follows the corresponding
3870 name, zero terminated. The names are in alphabetical order.
3871
3872 37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
3873 case instead of 255. Making it the same both with and without UTF-8 support
3874 means that the same test output works with both.
3875
3876 38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
3877 calling malloc() with a zero argument.
3878
3879 39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
3880 optimization. I've improved things by keeping a bitmap of backreferences with
3881 numbers 1-31 so that if .* occurs inside capturing brackets that are not in
3882 fact referenced, the optimization can be applied. It is unlikely that a
3883 relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
3884 the match to follow \n) will appear inside brackets with a number greater than
3885 31, but if it does, any back reference > 31 suppresses the optimization.
3886
3887 40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
3888 of disabling numbered capturing parentheses. Any opening parenthesis that is
3889 not followed by ? behaves as if it were followed by ?: but named parentheses
3890 can still be used for capturing (and they will acquire numbers in the usual
3891 way).
3892
3893 41. Redesigned the return codes from the match() function into yes/no/error so
3894 that errors can be passed back from deep inside the nested calls. A malloc
3895 failure while inside a recursive subpattern call now causes the
3896 PCRE_ERROR_NOMEMORY return instead of quietly going wrong.
3897
3898 42. It is now possible to set a limit on the number of times the match()
3899 function is called in a call to pcre_exec(). This facility makes it possible to
3900 limit the amount of recursion and backtracking, though not in a directly
3901 obvious way, because the match() function is used in a number of different
3902 circumstances. The count starts from zero for each position in the subject
3903 string (for non-anchored patterns). The default limit is, for compatibility, a
3904 large number, namely 10 000 000. You can change this in two ways:
3905
3906 (a) When configuring PCRE before making, you can use --with-match-limit=n
3907 to set a default value for the compiled library.
3908
3909 (b) For each call to pcre_exec(), you can pass a pcre_extra block in which
3910 a different value is set. See 45 below.
3911
3912 If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
3913
3914 43. Added a new function pcre_config(int, void *) to enable run-time extraction
3915 of things that can be changed at compile time. The first argument specifies
3916 what is wanted and the second points to where the information is to be placed.
3917 The current list of available information is:
3918
3919 PCRE_CONFIG_UTF8
3920
3921 The output is an integer that is set to one if UTF-8 support is available;
3922 otherwise it is set to zero.
3923
3924 PCRE_CONFIG_NEWLINE
3925
3926 The output is an integer that it set to the value of the code that is used for
3927 newline. It is either LF (10) or CR (13).
3928
3929 PCRE_CONFIG_LINK_SIZE
3930
3931 The output is an integer that contains the number of bytes used for internal
3932 linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.
3933
3934 PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
3935
3936 The output is an integer that contains the threshold above which the POSIX
3937 interface uses malloc() for output vectors. See item 31 above.
3938
3939 PCRE_CONFIG_MATCH_LIMIT
3940
3941 The output is an unsigned integer that contains the default limit of the number
3942 of match() calls in a pcre_exec() execution. See 42 above.
3943
3944 44. pcretest has been upgraded by the addition of the -C option. This causes it
3945 to extract all the available output from the new pcre_config() function, and to
3946 output it. The program then exits immediately.
3947
3948 45. A need has arisen to pass over additional data with calls to pcre_exec() in
3949 order to support additional features. One way would have been to define
3950 pcre_exec2() (for example) with extra arguments, but this would not have been
3951 extensible, and would also have required all calls to the original function to
3952 be mapped to the new one. Instead, I have chosen to extend the mechanism that
3953 is used for passing in "extra" data from pcre_study().
3954
3955 The pcre_extra structure is now exposed and defined in pcre.h. It currently
3956 contains the following fields:
3957
3958 flags a bitmap indicating which of the following fields are set
3959 study_data opaque data from pcre_study()
3960 match_limit a way of specifying a limit on match() calls for a specific
3961 call to pcre_exec()
3962 callout_data data for callouts (see 49 below)
3963
3964 The flag bits are also defined in pcre.h, and are
3965
3966 PCRE_EXTRA_STUDY_DATA
3967 PCRE_EXTRA_MATCH_LIMIT
3968 PCRE_EXTRA_CALLOUT_DATA
3969
3970 The pcre_study() function now returns one of these new pcre_extra blocks, with
3971 the actual study data pointed to by the study_data field, and the
3972 PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
3973 before. That is, this change is entirely upwards-compatible and requires no
3974 change to existing code.
3975
3976 If you want to pass in additional data to pcre_exec(), you can either place it
3977 in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
3978 block.
3979
3980 46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
3981 data string contains the escape sequence \M, pcretest calls pcre_exec() several
3982 times with different match limits, until it finds the minimum value needed for
3983 pcre_exec() to complete. The value is then output. This can be instructive; for
3984 most simple matches the number is quite small, but for pathological cases it
3985 gets very large very quickly.
3986
3987 47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
3988 returns the size of the data block pointed to by the study_data field in a
3989 pcre_extra block, that is, the value that was passed as the argument to
3990 pcre_malloc() when PCRE was getting memory in which to place the information
3991 created by pcre_study(). The fourth argument should point to a size_t variable.
3992 pcretest has been extended so that this information is shown after a successful
3993 pcre_study() call when information about the compiled regex is being displayed.
3994
3995 48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
3996 because what follows is always an absolute path. (Later: it turns out that this
3997 is more than cosmetic for MinGW, because it doesn't like empty path
3998 components.)
3999
4000 49. Some changes have been made to the callout feature (see 28 above):
4001
4002 (i) A callout function now has three choices for what it returns:
4003
4004 0 => success, carry on matching
4005 > 0 => failure at this point, but backtrack if possible
4006 < 0 => serious error, return this value from pcre_exec()
4007
4008 Negative values should normally be chosen from the set of PCRE_ERROR_xxx
4009 values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
4010 "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
4011 use by callout functions. It will never be used by PCRE itself.
4012
4013 (ii) The pcre_extra structure (see 45 above) has a void * field called
4014 callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
4015 pcre_callout_block structure has a field of the same name. The contents of
4016 the field passed in the pcre_extra structure are passed to the callout
4017 function in the corresponding field in the callout block. This makes it
4018 easier to use the same callout-containing regex from multiple threads. For
4019 testing, the pcretest program has a new data escape
4020
4021 \C*n pass the number n (may be negative) as callout_data
4022
4023 If the callout function in pcretest receives a non-zero value as
4024 callout_data, it returns that value.
4025
4026 50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
4027 there were some redundant $(CFLAGS) in commands that are now specified as
4028 $(LINK), which already includes $(CFLAGS).
4029
4030 51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
4031 has been compiled with UTF-8 support *and* pcre_compile() has been compiled
4032 with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
4033 one-byte characters throughout. Note that case-insensitive matching applies
4034 only to characters whose values are less than 256. PCRE doesn't support the
4035 notion of cases for higher-valued characters.
4036
4037 (i) A character class whose characters are all within 0-255 is handled as
4038 a bit map, and the map is inverted for negative classes. Previously, a
4039 character > 255 always failed to match such a class; however it should
4040 match if the class was a negative one (e.g. [^ab]). This has been fixed.
4041
4042 (ii) A negated character class with a single character < 255 is coded as
4043 "not this character" (OP_NOT). This wasn't working properly when the test
4044 character was multibyte, either singly or repeated.
4045
4046 (iii) Repeats of multibyte characters are now handled correctly in UTF-8
4047 mode, for example: \x{100}{2,3}.
4048
4049 (iv) The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
4050 singly or repeated) now correctly test multibyte characters. However,
4051 PCRE doesn't recognize any characters with values greater than 255 as
4052 digits, spaces, or word characters. Such characters always match \D, \S,
4053 and \W, and never match \d, \s, or \w.
4054
4055 (v) Classes may now contain characters and character ranges with values
4056 greater than 255. For example: [ab\x{100}-\x{400}].
4057
4058 (vi) pcregrep now has a --utf-8 option (synonym -u) which makes it call
4059 PCRE in UTF-8 mode.
4060
4061 52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
4062 PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
4063 retained for backwards compatibility. (Note that LASTLITERAL is also a byte
4064 value.)
4065
4066 53. The single man page has become too large. I have therefore split it up into
4067 a number of separate man pages. These also give rise to individual HTML pages;
4068 these are now put in a separate directory, and there is an index.html page that
4069 lists them all. Some hyperlinking between the pages has been installed.
4070
4071 54. Added convenience functions for handling named capturing parentheses.
4072
4073 55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
4074 aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
4075 true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
4076 are faulted.
4077
4078 56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
4079 calling configure. These values are used when compiling the dftables.c program
4080 which is run to generate the source of the default character tables. They
4081 default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
4082 you will need to set these values.
4083
4084 57. Updated the building process for Windows DLL, as provided by Fred Cox.
4085
4086
4087 Version 3.9 02-Jan-02
4088 ---------------------
4089
4090 1. A bit of extraneous text had somehow crept into the pcregrep documentation.
4091
4092 2. If --disable-static was given, the building process failed when trying to
4093 build pcretest and pcregrep. (For some reason it was using libtool to compile
4094 them, which is not right, as they aren't part of the library.)
4095
4096
4097 Version 3.8 18-Dec-01
4098 ---------------------
4099
4100 1. The experimental UTF-8 code was completely screwed up. It was packing the
4101 bytes in the wrong order. How dumb can you get?
4102
4103
4104 Version 3.7 29-Oct-01
4105 ---------------------
4106
4107 1. In updating pcretest to check change 1 of version 3.6, I screwed up.
4108 This caused pcretest, when used on the test data, to segfault. Unfortunately,
4109 this didn't happen under Solaris 8, where I normally test things.
4110
4111 2. The Makefile had to be changed to make it work on BSD systems, where 'make'
4112 doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
4113 isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
4114 this fix an hour or so after the initial 3.7 release.)
4115
4116
4117 Version 3.6 23-Oct-01
4118 ---------------------
4119
4120 1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
4121 offsets passed as NULL with zero offset count.
4122
4123 2. The config.guess and config.sub files had not been updated when I moved to
4124 the latest autoconf.
4125
4126
4127 Version 3.5 15-Aug-01
4128 ---------------------
4129
4130 1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
4131 had been forgotten.
4132
4133 2. By using declared but undefined structures, we can avoid using "void"
4134 definitions in pcre.h while keeping the internal definitions of the structures
4135 private.
4136
4137 3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
4138 user point of view, this means that both static and shared libraries are built
4139 by default, but this can be individually controlled. More of the work of
4140 handling this static/shared cases is now inside libtool instead of PCRE's make
4141 file.
4142
4143 4. The pcretest utility is now installed along with pcregrep because it is
4144 useful for users (to test regexs) and by doing this, it automatically gets
4145 relinked by libtool. The documentation has been turned into a man page, so
4146 there are now .1, .txt, and .html versions in /doc.
4147
4148 5. Upgrades to pcregrep:
4149 (i) Added long-form option names like gnu grep.
4150 (ii) Added --help to list all options with an explanatory phrase.
4151 (iii) Added -r, --recursive to recurse into sub-directories.
4152 (iv) Added -f, --file to read patterns from a file.
4153
4154 6. pcre_exec() was referring to its "code" argument before testing that
4155 argument for NULL (and giving an error if it was NULL).
4156
4157 7. Upgraded Makefile.in to allow for compiling in a different directory from
4158 the source directory.
4159
4160 8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
4161 options bits, the pointer it was passed was to an int instead of to an unsigned
4162 long int. This mattered only on 64-bit systems.
4163
4164 9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
4165 generated) instead of pcre.in, which it its source. Also made the same change
4166 in several of the .c files.
4167
4168 10. A new release of gcc defines printf() as a macro, which broke pcretest
4169 because it had an ifdef in the middle of a string argument for printf(). Fixed
4170 by using separate calls to printf().
4171
4172 11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
4173 script, to force use of CR or LF instead of \n in the source. On non-Unix
4174 systems, the value can be set in config.h.
4175
4176 12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
4177 absolute limit. Changed the text of the error message to make this clear, and
4178 likewise updated the man page.
4179
4180 13. The limit of 99 on the number of capturing subpatterns has been removed.
4181 The new limit is 65535, which I hope will not be a "real" limit.
4182
4183
4184 Version 3.4 22-Aug-00
4185 ---------------------
4186
4187 1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.
4188
4189 2. Diagnose condition (?(0) as an error instead of crashing on matching.
4190
4191
4192 Version 3.3 01-Aug-00
4193 ---------------------
4194
4195 1. If an octal character was given, but the value was greater than \377, it
4196 was not getting masked to the least significant bits, as documented. This could
4197 lead to crashes in some systems.
4198
4199 2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
4200 the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.
4201
4202 3. Added the functions pcre_free_substring() and pcre_free_substring_list().
4203 These just pass their arguments on to (pcre_free)(), but they are provided
4204 because some uses of PCRE bind it to non-C systems that can call its functions,
4205 but cannot call free() or pcre_free() directly.
4206
4207 4. Add "make test" as a synonym for "make check". Corrected some comments in
4208 the Makefile.
4209
4210 5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
4211 Makefile.
4212
4213 6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
4214 command called pgrep for grepping around the active processes.
4215
4216 7. Added the beginnings of support for UTF-8 character strings.
4217
4218 8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
4219 RANLIB to ./ltconfig so that they are used by libtool. I think these are all
4220 the relevant ones. (AR is not passed because ./ltconfig does its own figuring
4221 out for the ar command.)
4222
4223
4224 Version 3.2 12-May-00
4225 ---------------------
4226
4227 This is purely a bug fixing release.
4228
4229 1. If the pattern /((Z)+|A)*/ was matched agained ZABCDEFG it matched Z instead
4230 of ZA. This was just one example of several cases that could provoke this bug,
4231 which was introduced by change 9 of version 2.00. The code for breaking
4232 infinite loops after an iteration that matches an empty string was't working
4233 correctly.
4234
4235 2. The pcretest program was not imitating Perl correctly for the pattern /a*/g
4236 when matched against abbab (for example). After matching an empty string, it
4237 wasn't forcing anchoring when setting PCRE_NOTEMPTY for the next attempt; this
4238 caused it to match further down the string than it should.
4239
4240 3. The code contained an inclusion of sys/types.h. It isn't clear why this
4241 was there because it doesn't seem to be needed, and it causes trouble on some
4242 systems, as it is not a Standard C header. It has been removed.
4243
4244 4. Made 4 silly changes to the source to avoid stupid compiler warnings that
4245 were reported on the Macintosh. The changes were from
4246
4247 while ((c = *(++ptr)) != 0 && c != '\n');
4248 to
4249 while ((c = *(++ptr)) != 0 && c != '\n') ;
4250
4251 Totally extraordinary, but if that's what it takes...
4252
4253 5. PCRE is being used in one environment where neither memmove() nor bcopy() is
4254 available. Added HAVE_BCOPY and an autoconf test for it; if neither
4255 HAVE_MEMMOVE nor HAVE_BCOPY is set, use a built-in emulation function which
4256 assumes the way PCRE uses memmove() (always moving upwards).
4257
4258 6. PCRE is being used in one environment where strchr() is not available. There
4259 was only one use in pcre.c, and writing it out to avoid strchr() probably gives
4260 faster code anyway.
4261
4262
4263 Version 3.1 09-Feb-00
4264 ---------------------
4265
4266 The only change in this release is the fixing of some bugs in Makefile.in for
4267 the "install" target:
4268
4269 (1) It was failing to install pcreposix.h.
4270
4271 (2) It was overwriting the pcre.3 man page with the pcreposix.3 man page.
4272
4273
4274 Version 3.0 01-Feb-00
4275 ---------------------
4276
4277 1. Add support for the /+ modifier to perltest (to output $` like it does in
4278 pcretest).
4279
4280 2. Add support for the /g modifier to perltest.
4281
4282 3. Fix pcretest so that it behaves even more like Perl for /g when the pattern
4283 matches null strings.
4284
4285 4. Fix perltest so that it doesn't do unwanted things when fed an empty
4286 pattern. Perl treats empty patterns specially - it reuses the most recent
4287 pattern, which is not what we want. Replace // by /(?#)/ in order to avoid this
4288 effect.
4289
4290 5. The POSIX interface was broken in that it was just handing over the POSIX
4291 captured string vector to pcre_exec(), but (since release 2.00) PCRE has
4292 required a bigger vector, with some working space on the end. This means that
4293 the POSIX wrapper now has to get and free some memory, and copy the results.
4294
4295 6. Added some simple autoconf support, placing the test data and the
4296 documentation in separate directories, re-organizing some of the
4297 information files, and making it build pcre-config (a GNU standard). Also added
4298 libtool support for building PCRE as a shared library, which is now the
4299 default.
4300
4301 7. Got rid of the leading zero in the definition of PCRE_MINOR because 08 and
4302 09 are not valid octal constants. Single digits will be used for minor values
4303 less than 10.
4304
4305 8. Defined REG_EXTENDED and REG_NOSUB as zero in the POSIX header, so that
4306 existing programs that set these in the POSIX interface can use PCRE without
4307 modification.
4308
4309 9. Added a new function, pcre_fullinfo() with an extensible interface. It can
4310 return all that pcre_info() returns, plus additional data. The pcre_info()
4311 function is retained for compatibility, but is considered to be obsolete.
4312
4313 10. Added experimental recursion feature (?R) to handle one common case that
4314 Perl 5.6 will be able to do with (?p{...}).
4315
4316 11. Added support for POSIX character classes like [:alpha:], which Perl is
4317 adopting.
4318
4319
4320 Version 2.08 31-Aug-99
4321 ----------------------
4322
4323 1. When startoffset was not zero and the pattern began with ".*", PCRE was not
4324 trying to match at the startoffset position, but instead was moving forward to
4325 the next newline as if a previous match had failed.
4326
4327 2. pcretest was not making use of PCRE_NOTEMPTY when repeating for /g and /G,
4328 and could get into a loop if a null string was matched other than at the start
4329 of the subject.
4330
4331 3. Added definitions of PCRE_MAJOR and PCRE_MINOR to pcre.h so the version can
4332 be distinguished at compile time, and for completeness also added PCRE_DATE.
4333
4334 5. Added Paul Sokolovsky's minor changes to make it easy to compile a Win32 DLL
4335 in GnuWin32 environments.
4336
4337
4338 Version 2.07 29-Jul-99
4339 ----------------------
4340
4341 1. The documentation is now supplied in plain text form and HTML as well as in
4342 the form of man page sources.
4343
4344 2. C++ compilers don't like assigning (void *) values to other pointer types.
4345 In particular this affects malloc(). Although there is no problem in Standard
4346 C, I've put in casts to keep C++ compilers happy.
4347
4348 3. Typo on pcretest.c; a cast of (unsigned char *) in the POSIX regexec() call
4349 should be (const char *).
4350
4351 4. If NOPOSIX is defined, pcretest.c compiles without POSIX support. This may
4352 be useful for non-Unix systems who don't want to bother with the POSIX stuff.
4353 However, I haven't made this a standard facility. The documentation doesn't
4354 mention it, and the Makefile doesn't support it.
4355
4356 5. The Makefile now contains an "install" target, with editable destinations at
4357 the top of the file. The pcretest program is not installed.
4358
4359 6. pgrep -V now gives the PCRE version number and date.
4360
4361 7. Fixed bug: a zero repetition after a literal string (e.g. /abcde{0}/) was
4362 causing the entire string to be ignored, instead of just the last character.
4363
4364 8. If a pattern like /"([^\\"]+|\\.)*"/ is applied in the normal way to a
4365 non-matching string, it can take a very, very long time, even for strings of
4366 quite modest length, because of the nested recursion. PCRE now does better in
4367 some of these cases. It does this by remembering the last required literal
4368 character in the pattern, and pre-searching the subject to ensure it is present
4369 before running the real match. In other words, it applies a heuristic to detect
4370 some types of certain failure quickly, and in the above example, if presented
4371 with a string that has no trailing " it gives "no match" very quickly.
4372
4373 9. A new runtime option PCRE_NOTEMPTY causes null string matches to be ignored;
4374 other alternatives are tried instead.
4375
4376
4377 Version 2.06 09-Jun-99
4378 ----------------------
4379
4380 1. Change pcretest's output for amount of store used to show just the code
4381 space, because the remainder (the data block) varies in size between 32-bit and
4382 64-bit systems.
4383
4384 2. Added an extra argument to pcre_exec() to supply an offset in the subject to
4385 start matching at. This allows lookbehinds to work when searching for multiple
4386 occurrences in a string.
4387
4388 3. Added additional options to pcretest for testing multiple occurrences:
4389
4390 /+ outputs the rest of the string that follows a match
4391 /g loops for multiple occurrences, using the new startoffset argument
4392 /G loops for multiple occurrences by passing an incremented pointer
4393
4394 4. PCRE wasn't doing the "first character" optimization for patterns starting
4395 with \b or \B, though it was doing it for other lookbehind assertions. That is,
4396 it wasn't noticing that a match for a pattern such as /\bxyz/ has to start with
4397 the letter 'x'. On long subject strings, this gives a significant speed-up.
4398
4399
4400 Version 2.05 21-Apr-99
4401 ----------------------
4402
4403 1. Changed the type of magic_number from int to long int so that it works
4404 properly on 16-bit systems.
4405
4406 2. Fixed a bug which caused patterns starting with .* not to work correctly
4407 when the subject string contained newline characters. PCRE was assuming
4408 anchoring for such patterns in all cases, which is not correct because .* will
4409 not pass a newline unless PCRE_DOTALL is set. It now assumes anchoring only if
4410 DOTALL is set at top level; otherwise it knows that patterns starting with .*
4411 must be retried after every newline in the subject.
4412
4413
4414 Version 2.04 18-Feb-99
4415 ----------------------
4416
4417 1. For parenthesized subpatterns with repeats whose minimum was zero, the
4418 computation of the store needed to hold the pattern was incorrect (too large).
4419 If such patterns were nested a few deep, this could multiply and become a real
4420 problem.
4421
4422 2. Added /M option to pcretest to show the memory requirement of a specific
4423 pattern. Made -m a synonym of -s (which does this globally) for compatibility.
4424
4425 3. Subpatterns of the form (regex){n,m} (i.e. limited maximum) were being
4426 compiled in such a way that the backtracking after subsequent failure was
4427 pessimal. Something like (a){0,3} was compiled as (a)?(a)?(a)? instead of
4428 ((a)((a)(a)?)?)? with disastrous performance if the maximum was of any size.
4429
4430
4431 Version 2.03 02-Feb-99
4432 ----------------------
4433
4434 1. Fixed typo and small mistake in man page.
4435
4436 2. Added 4th condition (GPL supersedes if conflict) and created separate
4437 LICENCE file containing the conditions.
4438
4439 3. Updated pcretest so that patterns such as /abc\/def/ work like they do in
4440 Perl, that is the internal \ allows the delimiter to be included in the
4441 pattern. Locked out the use of \ as a delimiter. If \ immediately follows
4442 the final delimiter, add \ to the end of the pattern (to test the error).
4443
4444 4. Added the convenience functions for extracting substrings after a successful
4445 match. Updated pcretest to make it able to test these functions.
4446
4447
4448 Version 2.02 14-Jan-99
4449 ----------------------
4450
4451 1. Initialized the working variables associated with each extraction so that
4452 their saving and restoring doesn't refer to uninitialized store.
4453
4454 2. Put dummy code into study.c in order to trick the optimizer of the IBM C
4455 compiler for OS/2 into generating correct code. Apparently IBM isn't going to
4456 fix the problem.
4457
4458 3. Pcretest: the timing code wasn't using LOOPREPEAT for timing execution
4459 calls, and wasn't printing the correct value for compiling calls. Increased the
4460 default value of LOOPREPEAT, and the number of significant figures in the
4461 times.
4462
4463 4. Changed "/bin/rm" in the Makefile to "-rm" so it works on Windows NT.
4464
4465 5. Renamed "deftables" as "dftables" to get it down to 8 characters, to avoid
4466 a building problem on Windows NT with a FAT file system.
4467
4468
4469 Version 2.01 21-Oct-98
4470 ----------------------
4471
4472 1. Changed the API for pcre_compile() to allow for the provision of a pointer
4473 to character tables built by pcre_maketables() in the current locale. If NULL
4474 is passed, the default tables are used.
4475
4476
4477 Version 2.00 24-Sep-98
4478 ----------------------
4479
4480 1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
4481 it any more.
4482
4483 2. Allow quantification of (?>) groups, and make it work correctly.
4484
4485 3. The first character computation wasn't working for (?>) groups.
4486
4487 4. Correct the implementation of \Z (it is permitted to match on the \n at the
4488 end of the subject) and add 5.005's \z, which really does match only at the
4489 very end of the subject.
4490
4491 5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.
4492
4493 6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
4494 DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
4495 localized options. All options to pcre_study() were also removed.
4496
4497 7. Add other new features from 5.005:
4498
4499 $(?<= positive lookbehind
4500 $(?<! negative lookbehind
4501 (?imsx-imsx) added the unsetting capability
4502 such a setting is global if at outer level; local otherwise
4503 (?imsx-imsx:) non-capturing groups with option setting
4504 (?(cond)re|re) conditional pattern matching
4505
4506 A backreference to itself in a repeated group matches the previous
4507 captured string.
4508
4509 8. General tidying up of studying (both automatic and via "study")
4510 consequential on the addition of new assertions.
4511
4512 9. As in 5.005, unlimited repeated groups that could match an empty substring
4513 are no longer faulted at compile time. Instead, the loop is forcibly broken at
4514 runtime if any iteration does actually match an empty substring.
4515
4516 10. Include the RunTest script in the distribution.
4517
4518 11. Added tests from the Perl 5.005_02 distribution. This showed up a few
4519 discrepancies, some of which were old and were also with respect to 5.004. They
4520 have now been fixed.
4521
4522
4523 Version 1.09 28-Apr-98
4524 ----------------------
4525
4526 1. A negated single character class followed by a quantifier with a minimum
4527 value of one (e.g. [^x]{1,6} ) was not compiled correctly. This could lead to
4528 program crashes, or just wrong answers. This did not apply to negated classes
4529 containing more than one character, or to minima other than one.
4530
4531
4532 Version 1.08 27-Mar-98
4533 ----------------------
4534
4535 1. Add PCRE_UNGREEDY to invert the greediness of quantifiers.
4536
4537 2. Add (?U) and (?X) to set PCRE_UNGREEDY and PCRE_EXTRA respectively. The
4538 latter must appear before anything that relies on it in the pattern.
4539
4540
4541 Version 1.07 16-Feb-98
4542 ----------------------
4543
4544 1. A pattern such as /((a)*)*/ was not being diagnosed as in error (unlimited
4545 repeat of a potentially empty string).
4546
4547
4548 Version 1.06 23-Jan-98
4549 ----------------------
4550
4551 1. Added Markus Oberhumer's little patches for C++.
4552
4553 2. Literal strings longer than 255 characters were broken.
4554
4555
4556 Version 1.05 23-Dec-97
4557 ----------------------
4558
4559 1. Negated character classes containing more than one character were failing if
4560 PCRE_CASELESS was set at run time.
4561
4562
4563 Version 1.04 19-Dec-97
4564 ----------------------
4565
4566 1. Corrected the man page, where some "const" qualifiers had been omitted.
4567
4568 2. Made debugging output print "{0,xxx}" instead of just "{,xxx}" to agree with
4569 input syntax.
4570
4571 3. Fixed memory leak which occurred when a regex with back references was
4572 matched with an offsets vector that wasn't big enough. The temporary memory
4573 that is used in this case wasn't being freed if the match failed.
4574
4575 4. Tidied pcretest to ensure it frees memory that it gets.
4576
4577 5. Temporary memory was being obtained in the case where the passed offsets
4578 vector was exactly big enough.
4579
4580 6. Corrected definition of offsetof() from change 5 below.
4581
4582 7. I had screwed up change 6 below and broken the rules for the use of
4583 setjmp(). Now fixed.
4584
4585
4586 Version 1.03 18-Dec-97
4587 ----------------------
4588
4589 1. A erroneous regex with a missing opening parenthesis was correctly
4590 diagnosed, but PCRE attempted to access brastack[-1], which could cause crashes
4591 on some systems.
4592
4593 2. Replaced offsetof(real_pcre, code) by offsetof(real_pcre, code[0]) because
4594 it was reported that one broken compiler failed on the former because "code" is
4595 also an independent variable.
4596
4597 3. The erroneous regex a[]b caused an array overrun reference.
4598
4599 4. A regex ending with a one-character negative class (e.g. /[^k]$/) did not
4600 fail on data ending with that character. (It was going on too far, and checking
4601 the next character, typically a binary zero.) This was specific to the
4602 optimized code for single-character negative classes.
4603
4604 5. Added a contributed patch from the TIN world which does the following:
4605
4606 + Add an undef for memmove, in case the the system defines a macro for it.
4607
4608 + Add a definition of offsetof(), in case there isn't one. (I don't know
4609 the reason behind this - offsetof() is part of the ANSI standard - but
4610 it does no harm).
4611
4612 + Reduce the ifdef's in pcre.c using macro DPRINTF, thereby eliminating
4613 most of the places where whitespace preceded '#'. I have given up and
4614 allowed the remaining 2 cases to be at the margin.
4615
4616 + Rename some variables in pcre to eliminate shadowing. This seems very
4617 pedantic, but does no harm, of course.
4618
4619 6. Moved the call to setjmp() into its own function, to get rid of warnings
4620 from gcc -Wall, and avoided calling it at all unless PCRE_EXTRA is used.
4621
4622 7. Constructs such as \d{8,} were compiling into the equivalent of
4623 \d{8}\d{0,65527} instead of \d{8}\d* which didn't make much difference to the
4624 outcome, but in this particular case used more store than had been allocated,
4625 which caused the bug to be discovered because it threw up an internal error.
4626
4627 8. The debugging code in both pcre and pcretest for outputting the compiled
4628 form of a regex was going wrong in the case of back references followed by
4629 curly-bracketed repeats.
4630
4631
4632 Version 1.02 12-Dec-97
4633 ----------------------
4634
4635 1. Typos in pcre.3 and comments in the source fixed.
4636
4637 2. Applied a contributed patch to get rid of places where it used to remove
4638 'const' from variables, and fixed some signed/unsigned and uninitialized
4639 variable warnings.
4640
4641 3. Added the "runtest" target to Makefile.
4642
4643 4. Set default compiler flag to -O2 rather than just -O.
4644
4645
4646 Version 1.01 19-Nov-97
4647 ----------------------
4648
4649 1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
4650 like /([ab]*)*/, that is, for classes with more than one character in them.
4651
4652 2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
4653 as /((?>a*))*/ (a PCRE_EXTRA facility).
4654
4655
4656 Version 1.00 18-Nov-97
4657 ----------------------
4658
4659 1. Added compile-time macros to support systems such as SunOS4 which don't have
4660 memmove() or strerror() but have other things that can be used instead.
4661
4662 2. Arranged that "make clean" removes the executables.
4663
4664
4665 Version 0.99 27-Oct-97
4666 ----------------------
4667
4668 1. Fixed bug in code for optimizing classes with only one character. It was
4669 initializing a 32-byte map regardless, which could cause it to run off the end
4670 of the memory it had got.
4671
4672 2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
4673
4674
4675 Version 0.98 22-Oct-97
4676 ----------------------
4677
4678 1. Fixed bug in code for handling temporary memory usage when there are more
4679 back references than supplied space in the ovector. This could cause segfaults.
4680
4681
4682 Version 0.97 21-Oct-97
4683 ----------------------
4684
4685 1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
4686
4687 2. Optimized negated single characters not to use a bit map.
4688
4689 3. Brought error texts together as macro definitions; clarified some of them;
4690 fixed one that was wrong - it said "range out of order" when it meant "invalid
4691 escape sequence".
4692
4693 4. Changed some char * arguments to const char *.
4694
4695 5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
4696
4697 6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
4698 pcretest.
4699
4700
4701 Version 0.96 16-Oct-97
4702 ----------------------
4703
4704 1. Added a simple "pgrep" utility to the distribution.
4705
4706 2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
4707 unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
4708 where "ddd" means "one or more decimal digits".
4709
4710 3. Fixed serious bug. If a pattern had a back reference, but the call to
4711 pcre_exec() didn't supply a large enough ovector to record the related
4712 identifying subpattern, the match always failed. PCRE now remembers the number
4713 of the largest back reference, and gets some temporary memory in which to save
4714 the offsets during matching if necessary, in order to ensure that
4715 backreferences always work.
4716
4717 4. Increased the compatibility with Perl in a number of ways:
4718
4719 (a) . no longer matches \n by default; an option PCRE_DOTALL is provided
4720 to request this handling. The option can be set at compile or exec time.
4721
4722 (b) $ matches before a terminating newline by default; an option
4723 PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
4724 mode). The option can be set at compile or exec time.
4725
4726 (c) The handling of \ followed by a digit other than 0 is now supposed to be
4727 the same as Perl's. If the decimal number it represents is less than 10
4728 or there aren't that many previous left capturing parentheses, an octal
4729 escape is read. Inside a character class, it's always an octal escape,
4730 even if it is a single digit.
4731
4732 (d) An escaped but undefined alphabetic character is taken as a literal,
4733 unless PCRE_EXTRA is set. Currently this just reserves the remaining
4734 escapes.
4735
4736 (e) {0} is now permitted. (The previous item is removed from the compiled
4737 pattern).
4738
4739 5. Changed all the names of code files so that the basic parts are no longer
4740 than 10 characters, and abolished the teeny "globals.c" file.
4741
4742 6. Changed the handling of character classes; they are now done with a 32-byte
4743 bit map always.
4744
4745 7. Added the -d and /D options to pcretest to make it possible to look at the
4746 internals of compilation without having to recompile pcre.
4747
4748
4749 Version 0.95 23-Sep-97
4750 ----------------------
4751
4752 1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
4753 \x20 at the start of a run of normal characters. These were being treated as
4754 real characters, instead of the source characters being re-checked.
4755
4756
4757 Version 0.94 18-Sep-97
4758 ----------------------
4759
4760 1. The functions are now thread-safe, with the caveat that the global variables
4761 containing pointers to malloc() and free() or alternative functions are the
4762 same for all threads.
4763
4764 2. Get pcre_study() to generate a bitmap of initial characters for non-
4765 anchored patterns when this is possible, and use it if passed to pcre_exec().
4766
4767
4768 Version 0.93 15-Sep-97
4769 ----------------------
4770
4771 1. /(b)|(:+)/ was computing an incorrect first character.
4772
4773 2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
4774 but not actually doing anything yet.
4775
4776 3. Treat "-" characters in classes that cannot be part of ranges as literals,
4777 as Perl does (e.g. [-az] or [az-]).
4778
4779 4. Set the anchored flag if a branch starts with .* or .*? because that tests
4780 all possible positions.
4781
4782 5. Split up into different modules to avoid including unneeded functions in a
4783 compiled binary. However, compile and exec are still in one module. The "study"
4784 function is split off.
4785
4786 6. The character tables are now in a separate module whose source is generated
4787 by an auxiliary program - but can then be edited by hand if required. There are
4788 now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
4789 toupper() in the code.
4790
4791 7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
4792 make them global. Abolish the function for setting them, as the caller can now
4793 set them directly.
4794
4795
4796 Version 0.92 11-Sep-97
4797 ----------------------
4798
4799 1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
4800 (e.g. /a{1,3}/) was broken (I mis-optimized it).
4801
4802 2. Caseless matching was not working in character classes if the characters in
4803 the pattern were in upper case.
4804
4805 3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
4806
4807 4. Make PCRE_ANCHORED public and accept as a compile option.
4808
4809 5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
4810 PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
4811 pass them.
4812
4813 6. Give an error if bad option bits passed at compile or run time.
4814
4815 7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
4816 pcretest to cause it to pass that flag.
4817
4818 8. Add pcre_info(), to get the number of identifying subpatterns, the stored
4819 options, and the first character, if set.
4820
4821 9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
4822
4823
4824 Version 0.91 10-Sep-97
4825 ----------------------
4826
4827 1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
4828 match the empty string as in /(a*)*/. It was looping and ultimately crashing.
4829
4830 2. PCRE was looping on encountering an indefinitely repeated back reference to
4831 a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
4832 Perl does - treats the match as successful.
4833
4834 ****

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