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Revision 430 - (hide annotations) (download)
Tue Sep 1 16:29:46 2009 UTC (5 years, 2 months ago) by ph10
File size: 169945 byte(s)
Add -DPCRE_STATIC to configuration files when no shared library is built.

1 nigel 3 ChangeLog for PCRE
2     ------------------
3    
4 ph10 418 Version 8.00 ??-???-??
5     ----------------------
6    
7     1. The table for translating pcre_compile() error codes into POSIX error codes
8     was out-of-date, and there was no check on the pcre_compile() error code
9     being within the table. This could lead to an OK return being given in
10     error.
11 ph10 419
12     2. Changed the call to open a subject file in pcregrep from fopen(pathname,
13     "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
14     in a Windows environment.
15 ph10 420
16     3. The pcregrep --count option prints the count for each file even when it is
17     zero, as does GNU grep. However, pcregrep was also printing all files when
18     --files-with-matches was added. Now, when both options are given, it prints
19     counts only for those files that have at least one match. (GNU grep just
20     prints the file name in this circumstance, but including the count seems
21     more useful - otherwise, why use --count?) Also ensured that the
22     combination -clh just lists non-zero counts, with no names.
23    
24 ph10 421 4. The long form of the pcregrep -F option was incorrectly implemented as
25     --fixed_strings instead of --fixed-strings. This is an incompatible change,
26     but it seems right to fix it, and I didn't think it was worth preserving
27     the old behaviour.
28    
29 ph10 422 5. The command line items --regex=pattern and --regexp=pattern were not
30     recognized by pcregrep, which required --regex pattern or --regexp pattern
31     (with a space rather than an '='). The man page documented the '=' forms,
32     which are compatible with GNU grep; these now work.
33    
34 ph10 423 6. No libpcreposix.pc file was created for pkg-config; there was just
35     libpcre.pc and libpcrecpp.pc. The omission has been rectified.
36    
37 ph10 425 7. Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
38     when UCP support is not needed, by modifying the Python script that
39     generates it from Unicode data files. This should not matter if the module
40     is correctly used as a library, but I received one complaint about 50K of
41     unwanted data. My guess is that the person linked everything into his
42     program rather than using a library. Anyway, it does no harm.
43    
44 ph10 426 8. A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
45     was a minimum greater than 1 for a wide character in a possessive
46     repetition. Chaos could result.
47    
48     9. The restrictions on what a pattern can contain when partial matching is
49     requested for pcre_exec() have been removed. All patterns can now be
50     partially matched by this function. In addition, if there are at least two
51     slots in the offset vector, the offsets of the first-encountered partial
52     match are set in them when PCRE_ERROR_PARTIAL is returned.
53    
54 ph10 428 10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
55     synonymous with PCRE_PARTIAL, for backwards compatibility, and
56     PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
57     and may be more useful for multi-segment matching, especially with
58     pcre_exec().
59 ph10 427
60 ph10 428 11. Partial matching with pcre_exec() is now more intuitive. A partial match
61     used to be given if ever the end of the subject was reached; now it is
62     given only if matching could not proceed because another character was
63     needed. This makes a difference in some odd cases such as Z(*FAIL) with the
64     string "Z", which now yields "no match" instead of "partial match". In the
65     case of pcre_dfa_exec(), "no match" is given if every matching path for the
66     final character ended with (*FAIL).
67    
68     12. Restarting a match using pcre_dfa_exec() after a partial match did not work
69     if the pattern had a "must contain" character that was already found in the
70     earlier partial match, unless partial matching was again requested. For
71     example, with the pattern /dog.(body)?/, the "must contain" character is
72     "g". If the first part-match was for the string "dog", restarting with
73     "sbody" failed.
74    
75 ph10 429 13. Added a pcredemo man page, created automatically from the pcredemo.c file,
76     so that the demonstration program is easily available in environments where
77     PCRE has not been installed from source.
78    
79 ph10 430 14. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
80     libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
81     library.
82    
83 ph10 418
84 ph10 412 Version 7.9 11-Apr-09
85 ph10 376 ---------------------
86    
87 ph10 392 1. When building with support for bzlib/zlib (pcregrep) and/or readline
88 ph10 376 (pcretest), all targets were linked against these libraries. This included
89     libpcre, libpcreposix, and libpcrecpp, even though they do not use these
90     libraries. This caused unwanted dependencies to be created. This problem
91 ph10 392 has been fixed, and now only pcregrep is linked with bzlib/zlib and only
92 ph10 376 pcretest is linked with readline.
93 ph10 392
94 ph10 376 2. The "typedef int BOOL" in pcre_internal.h that was included inside the
95     "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
96     moved outside it again, because FALSE and TRUE are already defined in AIX,
97     but BOOL is not.
98 ph10 392
99     3. The pcre_config() function was treating the PCRE_MATCH_LIMIT and
100 ph10 409 PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
101 ph10 392
102 ph10 376 4. The pcregrep documentation said spaces were inserted as well as colons (or
103     hyphens) following file names and line numbers when outputting matching
104 ph10 392 lines. This is not true; no spaces are inserted. I have also clarified the
105 ph10 376 wording for the --colour (or --color) option.
106 ph10 392
107 ph10 378 5. In pcregrep, when --colour was used with -o, the list of matching strings
108     was not coloured; this is different to GNU grep, so I have changed it to be
109     the same.
110 ph10 392
111 ph10 378 6. When --colo(u)r was used in pcregrep, only the first matching substring in
112 ph10 392 each matching line was coloured. Now it goes on to look for further matches
113     of any of the test patterns, which is the same behaviour as GNU grep.
114    
115     7. A pattern that could match an empty string could cause pcregrep to loop; it
116     doesn't make sense to accept an empty string match in pcregrep, so I have
117 ph10 379 locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
118     seems to be how GNU grep behaves.
119 ph10 392
120 ph10 380 8. The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
121 ph10 392 start or after a newline", because the conditional assertion was not being
122     correctly handled. The rule now is that both the assertion and what follows
123     in the first alternative must satisfy the test.
124    
125 ph10 405 9. If auto-callout was enabled in a pattern with a conditional group whose
126 ph10 399 condition was an assertion, PCRE could crash during matching, both with
127     pcre_exec() and pcre_dfa_exec().
128 ph10 392
129     10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
130     used for matching.
131    
132     11. Unicode property support in character classes was not working for
133 ph10 385 characters (bytes) greater than 127 when not in UTF-8 mode.
134 ph10 388
135 ph10 392 12. Added the -M command line option to pcretest.
136    
137 ph10 388 14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
138 ph10 389
139     15. Added the PCRE_NO_START_OPTIMIZE match-time option.
140 ph10 390
141 ph10 392 16. Added comments and documentation about mis-use of no_arg in the C++
142 ph10 390 wrapper.
143 ph10 392
144 ph10 391 17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
145 ph10 392 from Martin Jerabek that uses macro names for all relevant character and
146 ph10 391 string constants.
147 ph10 405
148 ph10 393 18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
149     SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
150 ph10 405 SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
151     these, but not everybody uses configure.
152    
153     19. A conditional group that had only one branch was not being correctly
154     recognized as an item that could match an empty string. This meant that an
155     enclosing group might also not be so recognized, causing infinite looping
156     (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
157     with the subject "ab", where knowledge that the repeated group can match
158 ph10 396 nothing is needed in order to break the loop.
159 ph10 405
160 ph10 397 20. If a pattern that was compiled with callouts was matched using pcre_dfa_
161 ph10 405 exec(), but without supplying a callout function, matching went wrong.
162    
163     21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
164     leak if the size of the offset vector was greater than 30. When the vector
165     is smaller, the saved offsets during recursion go onto a local stack
166     vector, but for larger vectors malloc() is used. It was failing to free
167     when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
168 ph10 400 error, in fact).
169 ph10 405
170 ph10 402 22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
171 ph10 405 heapframe that is used only when UTF-8 support is enabled. This caused no
172     problem, but was untidy.
173 ph10 376
174 ph10 405 23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
175     CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
176     included within another project.
177 ph10 411
178 ph10 407 24. Steven Van Ingelgem's patches to add more options to the CMake support,
179     slightly modified by me:
180 ph10 411
181     (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
182     not building pcregrep.
183    
184 ph10 407 (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
185 ph10 411 if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
186    
187 ph10 408 25. Forward references, both numeric and by name, in patterns that made use of
188     duplicate group numbers, could behave incorrectly or give incorrect errors,
189     because when scanning forward to find the reference group, PCRE was not
190     taking into account the duplicate group numbers. A pattern such as
191     ^X(?3)(a)(?|(b)|(q))(Y) is an example.
192 ph10 411
193     26. Changed a few more instances of "const unsigned char *" to USPTR, making
194     the feature of a custom pointer more persuasive (as requested by a user).
195 ph10 416
196 ph10 411 27. Wrapped the definitions of fileno and isatty for Windows, which appear in
197 ph10 416 pcretest.c, inside #ifndefs, because it seems they are sometimes already
198     pre-defined.
199 ph10 392
200 ph10 416 28. Added support for (*UTF8) at the start of a pattern.
201    
202 ph10 413 29. Arrange for flags added by the "release type" setting in CMake to be shown
203     in the configuration summary.
204 ph10 405
205 ph10 411
206 ph10 374 Version 7.8 05-Sep-08
207 ph10 349 ---------------------
208    
209     1. Replaced UCP searching code with optimized version as implemented for Ad
210     Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
211 ph10 351 stage table and inline lookup instead of a function, giving speed ups of 2
212     to 5 times on some simple patterns that I tested. Permission was given to
213     distribute the MultiStage2.py script that generates the tables (it's not in
214     the tarball, but is in the Subversion repository).
215 ph10 349
216 ph10 351 2. Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
217     scripts.
218 ph10 358
219 ph10 353 3. Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
220     a group with a zero qualifier. The result of the study could be incorrect,
221 ph10 358 or the function might crash, depending on the pattern.
222    
223     4. Caseless matching was not working for non-ASCII characters in back
224 ph10 354 references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
225 ph10 358 It now works when Unicode Property Support is available.
226    
227 ph10 355 5. In pcretest, an escape such as \x{de} in the data was always generating
228     a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
229     non-UTF-8 mode. If the value is greater than 255, it gives a warning about
230 ph10 358 truncation.
231 ph10 349
232 ph10 358 6. Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
233    
234 ph10 357 7. Added two (int) casts to pcregrep when printing the difference of two
235     pointers, in case they are 64-bit values.
236 ph10 371
237     8. Added comments about Mac OS X stack usage to the pcrestack man page and to
238     test 2 if it fails.
239    
240 ph10 359 9. Added PCRE_CALL_CONVENTION just before the names of all exported functions,
241 ph10 371 and a #define of that name to empty if it is not externally set. This is to
242     allow users of MSVC to set it if necessary.
243    
244     10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
245 ph10 359 the convenience functions in the pcre_get.c source file.
246 ph10 371
247 ph10 360 11. An option change at the start of a pattern that had top-level alternatives
248     could cause overwriting and/or a crash. This command provoked a crash in
249 ph10 371 some environments:
250    
251     printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
252    
253 ph10 360 This potential security problem was recorded as CVE-2008-2371.
254 ph10 371
255 ph10 361 12. For a pattern where the match had to start at the beginning or immediately
256     after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
257 ph10 371 pcre_dfa_exec() could read past the end of the passed subject if there was
258 ph10 361 no match. To help with detecting such bugs (e.g. with valgrind), I modified
259     pcretest so that it places the subject at the end of its malloc-ed buffer.
260 ph10 371
261 ph10 364 13. The change to pcretest in 12 above threw up a couple more cases when pcre_
262 ph10 371 exec() might read past the end of the data buffer in UTF-8 mode.
263    
264 ph10 364 14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
265 ph10 371 the data contained the byte 0x85 as part of a UTF-8 character within its
266     first line. This applied both to normal and DFA matching.
267    
268 ph10 366 15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
269 ph10 371 /^[^d]*?$/8 failed to match "abc".
270 ph10 351
271 ph10 371 16. Added a missing copyright notice to pcrecpp_internal.h.
272    
273     17. Make it more clear in the documentation that values returned from
274 ph10 368 pcre_exec() in ovector are byte offsets, not character counts.
275 ph10 357
276 ph10 371 18. Tidied a few places to stop certain compilers from issuing warnings.
277 ph10 368
278 ph10 373 19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
279     supplied by Stefan Weber. I made a further small update for 7.8 because
280 ph10 374 there is a change of source arrangements: the pcre_searchfuncs.c module is
281     replaced by pcre_ucd.c.
282 ph10 371
283 ph10 373
284 ph10 347 Version 7.7 07-May-08
285 ph10 321 ---------------------
286    
287     1. Applied Craig's patch to sort out a long long problem: "If we can't convert
288 ph10 345 a string to a long long, pretend we don't even have a long long." This is
289 ph10 321 done by checking for the strtoq, strtoll, and _strtoi64 functions.
290 ph10 345
291 ph10 322 2. Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
292     pre-7.6 versions, which defined a global no_arg variable instead of putting
293 ph10 332 it in the RE class. (See also #8 below.)
294 ph10 345
295     3. Remove a line of dead code, identified by coverity and reported by Nuno
296     Lopes.
297    
298 ph10 324 4. Fixed two related pcregrep bugs involving -r with --include or --exclude:
299 ph10 321
300 ph10 324 (1) The include/exclude patterns were being applied to the whole pathnames
301 ph10 345 of files, instead of just to the final components.
302    
303 ph10 324 (2) If there was more than one level of directory, the subdirectories were
304     skipped unless they satisfied the include/exclude conditions. This is
305     inconsistent with GNU grep (and could even be seen as contrary to the
306     pcregrep specification - which I improved to make it absolutely clear).
307     The action now is always to scan all levels of directory, and just
308     apply the include/exclude patterns to regular files.
309 ph10 345
310 ph10 325 5. Added the --include_dir and --exclude_dir patterns to pcregrep, and used
311 ph10 345 --exclude_dir in the tests to avoid scanning .svn directories.
312    
313 ph10 326 6. Applied Craig's patch to the QuoteMeta function so that it escapes the
314 ph10 345 NUL character as backslash + 0 rather than backslash + NUL, because PCRE
315 ph10 326 doesn't support NULs in patterns.
316 ph10 345
317     7. Added some missing "const"s to declarations of static tables in
318     pcre_compile.c and pcre_dfa_exec.c.
319    
320 ph10 328 8. Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
321 ph10 329 caused by fix #2 above. (Subsequently also a second patch to fix the
322 ph10 345 first patch. And a third patch - this was a messy problem.)
323 ph10 321
324 ph10 345 9. Applied Craig's patch to remove the use of push_back().
325    
326 ph10 332 10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
327     matching function regexec().
328 ph10 345
329     11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
330     which, however, unlike Perl's \g{...}, are subroutine calls, not back
331 ph10 333 references. PCRE supports relative numbers with this syntax (I don't think
332     Oniguruma does).
333 ph10 345
334     12. Previously, a group with a zero repeat such as (...){0} was completely
335 ph10 335 omitted from the compiled regex. However, this means that if the group
336     was called as a subroutine from elsewhere in the pattern, things went wrong
337 ph10 345 (an internal error was given). Such groups are now left in the compiled
338     pattern, with a new opcode that causes them to be skipped at execution
339 ph10 335 time.
340 ph10 345
341 ph10 341 13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
342     to the way PCRE behaves:
343 ph10 345
344 ph10 336 (a) A lone ] character is dis-allowed (Perl treats it as data).
345 ph10 345
346     (b) A back reference to an unmatched subpattern matches an empty string
347 ph10 336 (Perl fails the current match path).
348 ph10 345
349 ph10 341 (c) A data ] in a character class must be notated as \] because if the
350 ph10 345 first data character in a class is ], it defines an empty class. (In
351 ph10 341 Perl it is not possible to have an empty class.) The empty class []
352     never matches; it forces failure and is equivalent to (*FAIL) or (?!).
353     The negative empty class [^] matches any one character, independently
354     of the DOTALL setting.
355 ph10 345
356     14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
357 ph10 340 non-existent subpattern following a character class starting with ']' and
358     containing () gave an internal compiling error instead of "reference to
359     non-existent subpattern". Fortunately, when the pattern did exist, the
360 ph10 345 compiled code was correct. (When scanning forwards to check for the
361 ph10 340 existencd of the subpattern, it was treating the data ']' as terminating
362 ph10 345 the class, so got the count wrong. When actually compiling, the reference
363 ph10 340 was subsequently set up correctly.)
364 ph10 345
365 ph10 341 15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
366 ph10 345 it was being rejected as not supported by pcre_dfa_exec(), even though
367     other assertions are supported. I have made pcre_dfa_exec() support
368     (*FAIL).
369    
370 ph10 342 16. The implementation of 13c above involved the invention of a new opcode,
371 ph10 345 OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
372     cannot be changed at match time, I realized I could make a small
373     improvement to matching performance by compiling OP_ALLANY instead of
374     OP_ANY for "." when DOTALL was set, and then removing the runtime tests
375     on the OP_ANY path.
376    
377     17. Compiling pcretest on Windows with readline support failed without the
378 ph10 343 following two fixes: (1) Make the unistd.h include conditional on
379 ph10 345 HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
380    
381 ph10 344 18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
382 ph10 345 ncurses library to be included for pcretest when ReadLine support is
383     requested, but also to allow for it to be overridden. This patch came from
384     Daniel Bergström.
385 ph10 347
386 ph10 346 19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
387 ph10 347 as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
388     any errors with the current Unicode tables. Thanks to Peter Kankowski for
389     spotting this.
390 ph10 324
391 ph10 332
392 ph10 319 Version 7.6 28-Jan-08
393 ph10 300 ---------------------
394    
395 ph10 302 1. A character class containing a very large number of characters with
396     codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
397     overflow.
398 ph10 309
399     2. Patch to cut out the "long long" test in pcrecpp_unittest when
400     HAVE_LONG_LONG is not defined.
401    
402 ph10 303 3. Applied Christian Ehrlicher's patch to update the CMake build files to
403 ph10 304 bring them up to date and include new features. This patch includes:
404 ph10 309
405 ph10 304 - Fixed PH's badly added libz and libbz2 support.
406     - Fixed a problem with static linking.
407 ph10 312 - Added pcredemo. [But later removed - see 7 below.]
408 ph10 304 - Fixed dftables problem and added an option.
409     - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
410     HAVE_LONG_LONG.
411     - Added readline support for pcretest.
412 ph10 309 - Added an listing of the option settings after cmake has run.
413    
414 ph10 314 4. A user submitted a patch to Makefile that makes it easy to create
415     "pcre.dll" under mingw when using Configure/Make. I added stuff to
416     Makefile.am that cause it to include this special target, without
417     affecting anything else. Note that the same mingw target plus all
418     the other distribution libraries and programs are now supported
419     when configuring with CMake (see 6 below) instead of with
420     Configure/Make.
421 ph10 309
422 ph10 308 5. Applied Craig's patch that moves no_arg into the RE class in the C++ code.
423     This is an attempt to solve the reported problem "pcrecpp::no_arg is not
424 ph10 309 exported in the Windows port". It has not yet been confirmed that the patch
425     solves the problem, but it does no harm.
426 ph10 313
427 ph10 311 6. Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
428 ph10 319 NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
429 ph10 314 with CMake, and also correct the comment about stack recursion.
430 ph10 313
431 ph10 312 7. Remove the automatic building of pcredemo from the ./configure system and
432 ph10 313 from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
433     of a program that users should build themselves after PCRE is installed, so
434     building it automatically is not really right. What is more, it gave
435 ph10 312 trouble in some build environments.
436 ph10 300
437 ph10 319 8. Further tidies to CMakeLists.txt from Sheri and Christian.
438 ph10 308
439 ph10 319
440 ph10 298 Version 7.5 10-Jan-08
441 ph10 263 ---------------------
442    
443     1. Applied a patch from Craig: "This patch makes it possible to 'ignore'
444     values in parens when parsing an RE using the C++ wrapper."
445 ph10 286
446 ph10 264 2. Negative specials like \S did not work in character classes in UTF-8 mode.
447     Characters greater than 255 were excluded from the class instead of being
448     included.
449 ph10 286
450     3. The same bug as (2) above applied to negated POSIX classes such as
451 ph10 265 [:^space:].
452 ph10 286
453 ph10 267 4. PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
454     defined or documented. It seems to have been a typo for PCRE_STATIC, so
455 ph10 286 I have changed it.
456    
457 ph10 268 5. The construct (?&) was not diagnosed as a syntax error (it referenced the
458 ph10 286 first named subpattern) and a construct such as (?&a) would reference the
459     first named subpattern whose name started with "a" (in other words, the
460 ph10 272 length check was missing). Both these problems are fixed. "Subpattern name
461     expected" is now given for (?&) (a zero-length name), and this patch also
462     makes it give the same error for \k'' (previously it complained that that
463     was a reference to a non-existent subpattern).
464 ph10 286
465 ph10 269 6. The erroneous patterns (?+-a) and (?-+a) give different error messages;
466 ph10 286 this is right because (?- can be followed by option settings as well as by
467 ph10 269 digits. I have, however, made the messages clearer.
468 ph10 286
469 ph10 270 7. Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
470     than the number used in the conditional) now cause a compile-time error.
471     This is actually not compatible with Perl, which accepts such patterns, but
472     treats the conditional as always being FALSE (as PCRE used to), but it
473     seems to me that giving a diagnostic is better.
474 ph10 286
475 ph10 274 8. Change "alphameric" to the more common word "alphanumeric" in comments
476 ph10 275 and messages.
477 ph10 286
478     9. Fix two occurrences of "backslash" in comments that should have been
479     "backspace".
480    
481     10. Remove two redundant lines of code that can never be obeyed (their function
482     was moved elsewhere).
483    
484     11. The program that makes PCRE's Unicode character property table had a bug
485     which caused it to generate incorrect table entries for sequences of
486 ph10 277 characters that have the same character type, but are in different scripts.
487 ph10 286 It amalgamated them into a single range, with the script of the first of
488 ph10 277 them. In other words, some characters were in the wrong script. There were
489     thirteen such cases, affecting characters in the following ranges:
490 ph10 286
491 ph10 277 U+002b0 - U+002c1
492     U+0060c - U+0060d
493 ph10 286 U+0061e - U+00612
494 ph10 277 U+0064b - U+0065e
495     U+0074d - U+0076d
496     U+01800 - U+01805
497     U+01d00 - U+01d77
498     U+01d9b - U+01dbf
499     U+0200b - U+0200f
500     U+030fc - U+030fe
501     U+03260 - U+0327f
502     U+0fb46 - U+0fbb1
503     U+10450 - U+1049d
504 ph10 286
505 ph10 279 12. The -o option (show only the matching part of a line) for pcregrep was not
506     compatible with GNU grep in that, if there was more than one match in a
507     line, it showed only the first of them. It now behaves in the same way as
508     GNU grep.
509 ph10 286
510     13. If the -o and -v options were combined for pcregrep, it printed a blank
511     line for every non-matching line. GNU grep prints nothing, and pcregrep now
512     does the same. The return code can be used to tell if there were any
513     non-matching lines.
514    
515 ph10 289 14. Added --file-offsets and --line-offsets to pcregrep.
516    
517     15. The pattern (?=something)(?R) was not being diagnosed as a potentially
518 ph10 282 infinitely looping recursion. The bug was that positive lookaheads were not
519 ph10 286 being skipped when checking for a possible empty match (negative lookaheads
520     and both kinds of lookbehind were skipped).
521    
522 ph10 289 16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
523 ph10 284 inclusion of <windows.h> to before rather than after the definition of
524     INVALID_FILE_ATTRIBUTES (patch from David Byron).
525 ph10 263
526 ph10 289 17. Specifying a possessive quantifier with a specific limit for a Unicode
527 ph10 286 character property caused pcre_compile() to compile bad code, which led at
528     runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
529     are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
530     caused the error; without that there was no problem.
531 ph10 263
532 ph10 289 18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
533 ph10 286
534 ph10 289 19. Added --enable-pcretest-libreadline.
535 ph10 286
536 ph10 289 20. In pcrecpp.cc, the variable 'count' was incremented twice in
537 ph10 288 RE::GlobalReplace(). As a result, the number of replacements returned was
538 ph10 298 double what it should be. I removed one of the increments, but Craig sent a
539     later patch that removed the other one (the right fix) and added unit tests
540     that check the return values (which was not done before).
541 ph10 292
542 ph10 291 21. Several CMake things:
543 ph10 287
544 ph10 291 (1) Arranged that, when cmake is used on Unix, the libraries end up with
545 ph10 292 the names libpcre and libpcreposix, not just pcre and pcreposix.
546 ph10 288
547 ph10 292 (2) The above change means that pcretest and pcregrep are now correctly
548     linked with the newly-built libraries, not previously installed ones.
549 ph10 291
550 ph10 292 (3) Added PCRE_SUPPORT_LIBREADLINE, PCRE_SUPPORT_LIBZ, PCRE_SUPPORT_LIBBZ2.
551 ph10 298
552     22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
553     crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
554     UTF-8 newline character). The key issue is that the pattern starts .*;
555     this means that the match must be either at the beginning, or after a
556     newline. The bug was in the code for advancing after a failed match and
557     checking that the new position followed a newline. It was not taking
558 ph10 294 account of UTF-8 characters correctly.
559 ph10 298
560     23. PCRE was behaving differently from Perl in the way it recognized POSIX
561     character classes. PCRE was not treating the sequence [:...:] as a
562     character class unless the ... were all letters. Perl, however, seems to
563     allow any characters between [: and :], though of course it rejects as
564     unknown any "names" that contain non-letters, because all the known class
565     names consist only of letters. Thus, Perl gives an error for [[:1234:]],
566     for example, whereas PCRE did not - it did not recognize a POSIX character
567     class. This seemed a bit dangerous, so the code has been changed to be
568     closer to Perl. The behaviour is not identical to Perl, because PCRE will
569     diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
570     treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
571     Perl does, and where it didn't before.
572    
573 ph10 296 24. Rewrite so as to remove the single use of %n from pcregrep because in some
574     Windows environments %n is disabled by default.
575 ph10 292
576    
577 ph10 260 Version 7.4 21-Sep-07
578 ph10 230 ---------------------
579    
580     1. Change 7.3/28 was implemented for classes by looking at the bitmap. This
581 ph10 231 means that a class such as [\s] counted as "explicit reference to CR or
582     LF". That isn't really right - the whole point of the change was to try to
583     help when there was an actual mention of one of the two characters. So now
584     the change happens only if \r or \n (or a literal CR or LF) character is
585 ph10 230 encountered.
586 ph10 231
587     2. The 32-bit options word was also used for 6 internal flags, but the numbers
588     of both had grown to the point where there were only 3 bits left.
589     Fortunately, there was spare space in the data structure, and so I have
590     moved the internal flags into a new 16-bit field to free up more option
591 ph10 230 bits.
592 ph10 231
593     3. The appearance of (?J) at the start of a pattern set the DUPNAMES option,
594     but did not set the internal JCHANGED flag - either of these is enough to
595     control the way the "get" function works - but the PCRE_INFO_JCHANGED
596     facility is supposed to tell if (?J) was ever used, so now (?J) at the
597 ph10 230 start sets both bits.
598    
599 ph10 231 4. Added options (at build time, compile time, exec time) to change \R from
600     matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
601 ph10 230
602 ph10 243 5. doc/pcresyntax.html was missing from the distribution.
603    
604     6. Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
605 ph10 233 compatibility, even though it is no longer used.
606 ph10 243
607     7. Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
608 ph10 254 strtoull to pcrecpp.cc to select the available functions in WIN32 when the
609 ph10 259 windows.h file is present (where different names are used). [This was
610 ph10 257 reversed later after testing - see 16 below.]
611 ph10 243
612     8. Changed all #include <config.h> to #include "config.h". There were also
613 ph10 236 some further <pcre.h> cases that I changed to "pcre.h".
614 ph10 243
615 ph10 239 9. When pcregrep was used with the --colour option, it missed the line ending
616 ph10 243 sequence off the lines that it output.
617    
618     10. It was pointed out to me that arrays of string pointers cause lots of
619     relocations when a shared library is dynamically loaded. A technique of
620     using a single long string with a table of offsets can drastically reduce
621     these. I have refactored PCRE in four places to do this. The result is
622 ph10 240 dramatic:
623 ph10 243
624 ph10 240 Originally: 290
625     After changing UCP table: 187
626 ph10 243 After changing error message table: 43
627 ph10 240 After changing table of "verbs" 36
628     After changing table of Posix names 22
629 ph10 243
630 ph10 240 Thanks to the folks working on Gregex for glib for this insight.
631 ph10 247
632 ph10 244 11. --disable-stack-for-recursion caused compiling to fail unless -enable-
633 ph10 247 unicode-properties was also set.
634    
635 ph10 248 12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
636 ph10 231
637 ph10 253 13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
638     checked only for CRLF.
639 ph10 233
640 ph10 259 14. Added casts to pcretest.c to avoid compiler warnings.
641    
642 ph10 256 15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
643 ph10 253
644 ph10 257 16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
645 ph10 259 and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
646     entirely. This removes changes made in 7 above.
647 ph10 256
648 ph10 261 17. The CMake files have been updated, and there is now more information about
649     building with CMake in the NON-UNIX-USE document.
650 ph10 257
651 ph10 261
652 ph10 228 Version 7.3 28-Aug-07
653 ph10 157 ---------------------
654    
655 ph10 189 1. In the rejigging of the build system that eventually resulted in 7.1, the
656     line "#include <pcre.h>" was included in pcre_internal.h. The use of angle
657     brackets there is not right, since it causes compilers to look for an
658     installed pcre.h, not the version that is in the source that is being
659     compiled (which of course may be different). I have changed it back to:
660 ph10 197
661 ph10 189 #include "pcre.h"
662 ph10 197
663     I have a vague recollection that the change was concerned with compiling in
664     different directories, but in the new build system, that is taken care of
665     by the VPATH setting the Makefile.
666    
667 ph10 190 2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
668     when the subject happened to end in the byte 0x85 (e.g. if the last
669     character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
670     characters but of course it shouldn't be taken as a newline when it is part
671     of another character. The bug was that, for an unlimited repeat of . in
672     not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
673     characters when looking for a newline.
674 ph10 197
675     3. A small performance improvement in the DOTALL UTF-8 mode .* case.
676    
677     4. Debugging: adjusted the names of opcodes for different kinds of parentheses
678     in debug output.
679    
680 ph10 201 5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
681     long printing in the pcrecpp unittest when running under MinGW.
682 ph10 189
683 ph10 197 6. ESC_K was left out of the EBCDIC table.
684 ph10 189
685 ph10 197 7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
686     parentheses; I made it 1000, which seemed large enough. Unfortunately, the
687     limit also applies to "virtual nesting" when a pattern is recursive, and in
688     this case 1000 isn't so big. I have been able to remove this limit at the
689     expense of backing off one optimization in certain circumstances. Normally,
690     when pcre_exec() would call its internal match() function recursively and
691     immediately return the result unconditionally, it uses a "tail recursion"
692     feature to save stack. However, when a subpattern that can match an empty
693     string has an unlimited repetition quantifier, it no longer makes this
694     optimization. That gives it a stack frame in which to save the data for
695     checking that an empty string has been matched. Previously this was taken
696     from the 1000-entry workspace that had been reserved. So now there is no
697     explicit limit, but more stack is used.
698 ph10 189
699 ph10 200 8. Applied Daniel's patches to solve problems with the import/export magic
700     syntax that is required for Windows, and which was going wrong for the
701     pcreposix and pcrecpp parts of the library. These were overlooked when this
702     problem was solved for the main library.
703 ph10 197
704 ph10 202 9. There were some crude static tests to avoid integer overflow when computing
705     the size of patterns that contain repeated groups with explicit upper
706     limits. As the maximum quantifier is 65535, the maximum group length was
707     set at 30,000 so that the product of these two numbers did not overflow a
708     32-bit integer. However, it turns out that people want to use groups that
709     are longer than 30,000 bytes (though not repeat them that many times).
710     Change 7.0/17 (the refactoring of the way the pattern size is computed) has
711     made it possible to implement the integer overflow checks in a much more
712     dynamic way, which I have now done. The artificial limitation on group
713     length has been removed - we now have only the limit on the total length of
714     the compiled pattern, which depends on the LINK_SIZE setting.
715 ph10 208
716     10. Fixed a bug in the documentation for get/copy named substring when
717     duplicate names are permitted. If none of the named substrings are set, the
718     functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
719     empty string.
720    
721     11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E
722     instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error,
723     because the ] is interpreted as the first data character and the
724     terminating ] is not found. PCRE has been made compatible with Perl in this
725     regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could
726     cause memory overwriting.
727    
728 ph10 206 10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty
729     string has been matched (to stop an infinite loop). It was not recognizing
730 ph10 208 a conditional subpattern that could match an empty string if that
731 ph10 206 subpattern was within another subpattern. For example, it looped when
732 ph10 208 trying to match (((?(1)X|))*) but it was OK with ((?(1)X|)*) where the
733 ph10 206 condition was not nested. This bug has been fixed.
734 ph10 208
735 ph10 207 12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
736     past the start of the subject in the presence of bytes with the top bit
737     set, for example "\x8aBCD".
738 ph10 211
739 ph10 210 13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
740     (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
741 ph10 200
742 ph10 211 14. Optimized (?!) to (*FAIL).
743 ph10 202
744 ph10 212 15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
745     This restricts code points to be within the range 0 to 0x10FFFF, excluding
746     the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
747     full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
748     does: it's just the validity check that is more restrictive.
749 ph10 220
750     16. Inserted checks for integer overflows during escape sequence (backslash)
751     processing, and also fixed erroneous offset values for syntax errors during
752     backslash processing.
753    
754 ph10 214 17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
755 ph10 220 for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
756    
757 ph10 215 18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
758     caused an overrun.
759 ph10 220
760     19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
761     something other than just ASCII characters) inside a group that had an
762     unlimited repeat caused a loop at compile time (while checking to see
763     whether the group could match an empty string).
764    
765 ph10 217 20. Debugging a pattern containing \p or \P could cause a crash. For example,
766     [\P{Any}] did so. (Error in the code for printing property names.)
767 ph10 210
768 ph10 220 21. An orphan \E inside a character class could cause a crash.
769    
770     22. A repeated capturing bracket such as (A)? could cause a wild memory
771 ph10 218 reference during compilation.
772 ph10 220
773     23. There are several functions in pcre_compile() that scan along a compiled
774     expression for various reasons (e.g. to see if it's fixed length for look
775 ph10 218 behind). There were bugs in these functions when a repeated \p or \P was
776 ph10 220 present in the pattern. These operators have additional parameters compared
777     with \d, etc, and these were not being taken into account when moving along
778 ph10 218 the compiled data. Specifically:
779 ph10 220
780     (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
781     length.
782    
783     (b) An item such as \pL+ within a repeated group could cause crashes or
784 ph10 218 loops.
785 ph10 220
786 ph10 218 (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
787 ph10 220 "reference to non-existent subpattern" error.
788    
789 ph10 221 (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
790    
791 ph10 219 24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
792 ph10 220 characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
793 ph10 211
794 ph10 222 25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
795 ph10 218
796 ph10 227 26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
797 ph10 223 character were causing crashes (broken optimization).
798 ph10 227
799 ph10 224 27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
800 ph10 227 \p or \P) caused a compile-time loop.
801    
802 ph10 226 28. More problems have arisen in unanchored patterns when CRLF is a valid line
803     break. For example, the unstudied pattern [\r\n]A does not match the string
804     "\r\nA" because change 7.0/46 below moves the current point on by two
805     characters after failing to match at the start. However, the pattern \nA
806 ph10 227 *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
807     the same is true. There doesn't seem any very clean way out of this, but
808     what I have chosen to do makes the common cases work: PCRE now takes note
809     of whether there can be an explicit match for \r or \n anywhere in the
810     pattern, and if so, 7.0/46 no longer applies. As part of this change,
811     there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
812     pattern has explicit CR or LF references.
813 ph10 222
814 ph10 227 29. Added (*CR) etc for changing newline setting at start of pattern.
815 ph10 223
816 ph10 227
817 ph10 189 Version 7.2 19-Jun-07
818     ---------------------
819    
820 ph10 157 1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
821     which is apparently normally available under Windows.
822 ph10 159
823     2. Re-jig the pcregrep tests with different newline settings in an attempt
824     to make them independent of the local environment's newline setting.
825 ph10 157
826 ph10 160 3. Add code to configure.ac to remove -g from the CFLAGS default settings.
827 ph10 165
828 ph10 161 4. Some of the "internals" tests were previously cut out when the link size
829     was not 2, because the output contained actual offsets. The recent new
830 ph10 165 "Z" feature of pcretest means that these can be cut out, making the tests
831     usable with all link sizes.
832    
833 ph10 164 5. Implemented Stan Switzer's goto replacement for longjmp() when not using
834     stack recursion. This gives a massive performance boost under BSD, but just
835 ph10 165 a small improvement under Linux. However, it saves one field in the frame
836 ph10 164 in all cases.
837 ph10 172
838 ph10 166 6. Added more features from the forthcoming Perl 5.10:
839 ph10 172
840 ph10 166 (a) (?-n) (where n is a string of digits) is a relative subroutine or
841     recursion call. It refers to the nth most recently opened parentheses.
842 ph10 172
843 ph10 166 (b) (?+n) is also a relative subroutine call; it refers to the nth next
844 ph10 172 to be opened parentheses.
845    
846     (c) Conditions that refer to capturing parentheses can be specified
847 ph10 167 relatively, for example, (?(-2)... or (?(+3)...
848 ph10 172
849 ph10 168 (d) \K resets the start of the current match so that everything before
850 ph10 172 is not part of it.
851    
852 ph10 171 (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible).
853 ph10 172
854 ph10 171 (f) \g{name} is another synonym - part of Perl 5.10's unification of
855 ph10 172 reference syntax.
856 ph10 182
857 ph10 175 (g) (?| introduces a group in which the numbering of parentheses in each
858 ph10 182 alternative starts with the same number.
859 ph10 172
860 ph10 182 (h) \h, \H, \v, and \V match horizontal and vertical whitespace.
861    
862 ph10 172 7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and
863     PCRE_INFO_JCHANGED.
864    
865     8. A pattern such as (.*(.)?)* caused pcre_exec() to fail by either not
866     terminating or by crashing. Diagnosed by Viktor Griph; it was in the code
867 ph10 170 for detecting groups that can match an empty string.
868 ph10 159
869 ph10 172 9. A pattern with a very large number of alternatives (more than several
870     hundred) was running out of internal workspace during the pre-compile
871     phase, where pcre_compile() figures out how much memory will be needed. A
872     bit of new cunning has reduced the workspace needed for groups with
873     alternatives. The 1000-alternative test pattern now uses 12 bytes of
874     workspace instead of running out of the 4096 that are available.
875 ph10 182
876 ph10 176 10. Inserted some missing (unsigned int) casts to get rid of compiler warnings.
877 ph10 172
878 ph10 179 11. Applied patch from Google to remove an optimization that didn't quite work.
879     The report of the bug said:
880 ph10 182
881 ph10 179 pcrecpp::RE("a*").FullMatch("aaa") matches, while
882     pcrecpp::RE("a*?").FullMatch("aaa") does not, and
883 ph10 182 pcrecpp::RE("a*?\\z").FullMatch("aaa") does again.
884 ph10 185
885 ph10 184 12. If \p or \P was used in non-UTF-8 mode on a character greater than 127
886 ph10 185 it matched the wrong number of bytes.
887 ph10 172
888 ph10 179
889 ph10 155 Version 7.1 24-Apr-07
890 ph10 98 ---------------------
891    
892 ph10 111 1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
893 ph10 122 that is more "standard", making use of automake and other Autotools. There
894 ph10 99 is some re-arrangement of the files and adjustment of comments consequent
895     on this.
896 ph10 111
897     2. Part of the patch fixed a problem with the pcregrep tests. The test of -r
898     for recursive directory scanning broke on some systems because the files
899     are not scanned in any specific order and on different systems the order
900     was different. A call to "sort" has been inserted into RunGrepTest for the
901     approprate test as a short-term fix. In the longer term there may be an
902 ph10 100 alternative.
903 ph10 111
904 ph10 100 3. I had an email from Eric Raymond about problems translating some of PCRE's
905 ph10 111 man pages to HTML (despite the fact that I distribute HTML pages, some
906     people do their own conversions for various reasons). The problems
907     concerned the use of low-level troff macros .br and .in. I have therefore
908     removed all such uses from the man pages (some were redundant, some could
909 ph10 113 be replaced by .nf/.fi pairs). The 132html script that I use to generate
910     HTML has been updated to handle .nf/.fi and to complain if it encounters
911     .br or .in.
912 ph10 111
913 ph10 100 4. Updated comments in configure.ac that get placed in config.h.in and also
914 ph10 123 arranged for config.h to be included in the distribution, with the name
915 ph10 111 config.h.generic, for the benefit of those who have to compile without
916     Autotools (compare pcre.h, which is now distributed as pcre.h.generic).
917    
918     5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
919     Weber: (1) pcre_internal.h was missing some function renames; (2) updated
920 ph10 127 makevp.bat for the current PCRE, using the additional files
921 ph10 135 makevp_c.txt, makevp_l.txt, and pcregexp.pas.
922 ph10 111
923     6. A Windows user reported a minor discrepancy with test 2, which turned out
924     to be caused by a trailing space on an input line that had got lost in his
925 ph10 102 copy. The trailing space was an accident, so I've just removed it.
926 ph10 111
927 ph10 104 7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told
928 ph10 111 that is needed.
929    
930 ph10 105 8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c)
931     as "const" (a) because they are and (b) because it helps the PHP
932     maintainers who have recently made a script to detect big data structures
933 ph10 111 in the php code that should be moved to the .rodata section. I remembered
934     to update Builducptable as well, so it won't revert if ucptable.h is ever
935 ph10 105 re-created.
936 ph10 111
937     9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c,
938 ph10 107 pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in
939 ph10 111 order to be able to cut out the UTF-8 tables in the latter when UTF-8
940     support is not required. This saves 1.5-2K of code, which is important in
941 ph10 107 some applications.
942 ph10 111
943 ph10 110 Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c
944 ph10 111 so as not to refer to the tables, even though these functions will never be
945     called when UTF-8 support is disabled. Otherwise there are problems with a
946     shared library.
947    
948 ph10 118 10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:
949    
950     (a) It was defining its arguments as char * instead of void *.
951    
952 ph10 123 (b) It was assuming that all moves were upwards in memory; this was true
953     a long time ago when I wrote it, but is no longer the case.
954    
955 ph10 118 The emulated memove() is provided for those environments that have neither
956 ph10 123 memmove() nor bcopy(). I didn't think anyone used it these days, but that
957 ph10 118 is clearly not the case, as these two bugs were recently reported.
958 ph10 123
959 ph10 111 11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,
960 ph10 123 and Detrail to create the HTML documentation, the .txt form of the man
961     pages, and it removes trailing spaces from listed files. It also creates
962     pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter
963     case, it wraps all the #defines with #ifndefs. This script should be run
964 ph10 111 before "make dist".
965 ph10 123
966 ph10 115 12. Fixed two fairly obscure bugs concerned with quantified caseless matching
967     with Unicode property support.
968 ph10 123
969     (a) For a maximizing quantifier, if the two different cases of the
970     character were of different lengths in their UTF-8 codings (there are
971     some cases like this - I found 11), and the matching function had to
972 ph10 115 back up over a mixture of the two cases, it incorrectly assumed they
973     were both the same length.
974 ph10 123
975     (b) When PCRE was configured to use the heap rather than the stack for
976     recursion during matching, it was not correctly preserving the data for
977     the other case of a UTF-8 character when checking ahead for a match
978     while processing a minimizing repeat. If the check also involved
979 ph10 115 matching a wide character, but failed, corruption could cause an
980     erroneous result when trying to check for a repeat of the original
981     character.
982 ph10 123
983 ph10 116 13. Some tidying changes to the testing mechanism:
984 ph10 98
985 ph10 116 (a) The RunTest script now detects the internal link size and whether there
986     is UTF-8 and UCP support by running ./pcretest -C instead of relying on
987 ph10 123 values substituted by "configure". (The RunGrepTest script already did
988     this for UTF-8.) The configure.ac script no longer substitutes the
989     relevant variables.
990    
991 ph10 116 (b) The debugging options /B and /D in pcretest show the compiled bytecode
992     with length and offset values. This means that the output is different
993     for different internal link sizes. Test 2 is skipped for link sizes
994     other than 2 because of this, bypassing the problem. Unfortunately,
995     there was also a test in test 3 (the locale tests) that used /B and
996 ph10 123 failed for link sizes other than 2. Rather than cut the whole test out,
997     I have added a new /Z option to pcretest that replaces the length and
998     offset values with spaces. This is now used to make test 3 independent
999 ph10 122 of link size. (Test 2 will be tidied up later.)
1000 ph10 123
1001     14. If erroroffset was passed as NULL to pcre_compile, it provoked a
1002 ph10 122 segmentation fault instead of returning the appropriate error message.
1003 ph10 134
1004 ph10 131 15. In multiline mode when the newline sequence was set to "any", the pattern
1005 ph10 134 ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
1006     This doesn't seem right; it now treats the CRLF combination as the line
1007     ending, and so does not match in that case. It's only a pattern such as ^$
1008     that would hit this one: something like ^ABC$ would have failed after \r
1009     and then tried again after \r\n.
1010    
1011 ph10 131 16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
1012 ph10 134 in an attempt to make files that differ only in their line terminators
1013     compare equal. This works on Linux.
1014 ph10 142
1015 ph10 141 17. Under certain error circumstances pcregrep might try to free random memory
1016     as it exited. This is now fixed, thanks to valgrind.
1017 ph10 142
1018 ph10 141 19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
1019 ph10 142 "abc\r\n\r\n", it found an unwanted second match after the second \r. This
1020     was because its rules for how to advance for /g after matching an empty
1021 ph10 143 string at the end of a line did not allow for this case. They now check for
1022     it specially.
1023 ph10 150
1024     20. pcretest is supposed to handle patterns and data of any length, by
1025     extending its buffers when necessary. It was getting this wrong when the
1026 ph10 147 buffer for a data line had to be extended.
1027 ph10 150
1028 ph10 149 21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
1029 ph10 150 CRLF as a newline sequence.
1030 ph10 152
1031 ph10 151 22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
1032 ph10 152 out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
1033     I have nevertheless tidied it up.
1034 ph10 111
1035 ph10 152 23. Added some casts to kill warnings from HP-UX ia64 compiler.
1036 ph10 123
1037 ph10 153 24. Added a man page for pcre-config.
1038 ph10 152
1039 ph10 153
1040 nigel 93 Version 7.0 19-Dec-06
1041     ---------------------
1042    
1043     1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by
1044     moving to gcc 4.1.1.
1045    
1046     2. The -S option for pcretest uses setrlimit(); I had omitted to #include
1047     sys/time.h, which is documented as needed for this function. It doesn't
1048     seem to matter on Linux, but it showed up on some releases of OS X.
1049    
1050     3. It seems that there are systems where bytes whose values are greater than
1051     127 match isprint() in the "C" locale. The "C" locale should be the
1052     default when a C program starts up. In most systems, only ASCII printing
1053     characters match isprint(). This difference caused the output from pcretest
1054     to vary, making some of the tests fail. I have changed pcretest so that:
1055    
1056     (a) When it is outputting text in the compiled version of a pattern, bytes
1057     other than 32-126 are always shown as hex escapes.
1058    
1059     (b) When it is outputting text that is a matched part of a subject string,
1060     it does the same, unless a different locale has been set for the match
1061     (using the /L modifier). In this case, it uses isprint() to decide.
1062    
1063     4. Fixed a major bug that caused incorrect computation of the amount of memory
1064     required for a compiled pattern when options that changed within the
1065     pattern affected the logic of the preliminary scan that determines the
1066     length. The relevant options are -x, and -i in UTF-8 mode. The result was
1067     that the computed length was too small. The symptoms of this bug were
1068     either the PCRE error "internal error: code overflow" from pcre_compile(),
1069     or a glibc crash with a message such as "pcretest: free(): invalid next
1070     size (fast)". Examples of patterns that provoked this bug (shown in
1071     pcretest format) are:
1072    
1073     /(?-x: )/x
1074     /(?x)(?-x: \s*#\s*)/
1075     /((?i)[\x{c0}])/8
1076     /(?i:[\x{c0}])/8
1077    
1078     HOWEVER: Change 17 below makes this fix obsolete as the memory computation
1079     is now done differently.
1080    
1081     5. Applied patches from Google to: (a) add a QuoteMeta function to the C++
1082     wrapper classes; (b) implement a new function in the C++ scanner that is
1083     more efficient than the old way of doing things because it avoids levels of
1084     recursion in the regex matching; (c) add a paragraph to the documentation
1085     for the FullMatch() function.
1086    
1087     6. The escape sequence \n was being treated as whatever was defined as
1088     "newline". Not only was this contrary to the documentation, which states
1089     that \n is character 10 (hex 0A), but it also went horribly wrong when
1090     "newline" was defined as CRLF. This has been fixed.
1091    
1092     7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c)
1093     was being set to -1 for the "end of line" case (supposedly a value that no
1094     character can have). Though this value is never used (the check for end of
1095     line is "zero bytes in current character"), it caused compiler complaints.
1096     I've changed it to 0xffffffff.
1097    
1098     8. In pcre_version.c, the version string was being built by a sequence of
1099     C macros that, in the event of PCRE_PRERELEASE being defined as an empty
1100     string (as it is for production releases) called a macro with an empty
1101     argument. The C standard says the result of this is undefined. The gcc
1102     compiler treats it as an empty string (which was what was wanted) but it is
1103     reported that Visual C gives an error. The source has been hacked around to
1104     avoid this problem.
1105    
1106     9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows
1107     builds of pcretest, and changed the call to _setmode() to use _O_BINARY
1108     instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all
1109     of them did).
1110    
1111     10. Originally, pcretest opened its input and output without "b"; then I was
1112     told that "b" was needed in some environments, so it was added for release
1113     5.0 to both the input and output. (It makes no difference on Unix-like
1114     systems.) Later I was told that it is wrong for the input on Windows. I've
1115     now abstracted the modes into two macros, to make it easier to fiddle with
1116     them, and removed "b" from the input mode under Windows.
1117    
1118     11. Added pkgconfig support for the C++ wrapper library, libpcrecpp.
1119    
1120     12. Added -help and --help to pcretest as an official way of being reminded
1121     of the options.
1122    
1123     13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in
1124     and pcrecpp.cc because they annoy compilers at high warning levels.
1125    
1126     14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop.
1127    
1128     15. Fixed an occurrence of == in configure.ac that should have been = (shell
1129     scripts are not C programs :-) and which was not noticed because it works
1130     on Linux.
1131    
1132     16. pcretest is supposed to handle any length of pattern and data line (as one
1133     line or as a continued sequence of lines) by extending its input buffer if
1134     necessary. This feature was broken for very long pattern lines, leading to
1135     a string of junk being passed to pcre_compile() if the pattern was longer
1136     than about 50K.
1137    
1138     17. I have done a major re-factoring of the way pcre_compile() computes the
1139     amount of memory needed for a compiled pattern. Previously, there was code
1140     that made a preliminary scan of the pattern in order to do this. That was
1141     OK when PCRE was new, but as the facilities have expanded, it has become
1142     harder and harder to keep it in step with the real compile phase, and there
1143     have been a number of bugs (see for example, 4 above). I have now found a
1144     cunning way of running the real compile function in a "fake" mode that
1145     enables it to compute how much memory it would need, while actually only
1146     ever using a few hundred bytes of working memory and without too many
1147     tests of the mode. This should make future maintenance and development
1148     easier. A side effect of this work is that the limit of 200 on the nesting
1149     depth of parentheses has been removed (though this was never a serious
1150     limitation, I suspect). However, there is a downside: pcre_compile() now
1151     runs more slowly than before (30% or more, depending on the pattern). I
1152     hope this isn't a big issue. There is no effect on runtime performance.
1153    
1154     18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a
1155     newline (only possible for the last line of a file) and it was a
1156     pattern that set a locale (followed by /Lsomething), pcretest crashed.
1157    
1158     19. Added additional timing features to pcretest. (1) The -tm option now times
1159     matching only, not compiling. (2) Both -t and -tm can be followed, as a
1160     separate command line item, by a number that specifies the number of
1161     repeats to use when timing. The default is 50000; this gives better
1162     precision, but takes uncomfortably long for very large patterns.
1163    
1164     20. Extended pcre_study() to be more clever in cases where a branch of a
1165     subpattern has no definite first character. For example, (a*|b*)[cd] would
1166     previously give no result from pcre_study(). Now it recognizes that the
1167     first character must be a, b, c, or d.
1168    
1169     21. There was an incorrect error "recursive call could loop indefinitely" if
1170     a subpattern (or the entire pattern) that was being tested for matching an
1171     empty string contained only one non-empty item after a nested subpattern.
1172     For example, the pattern (?>\x{100}*)\d(?R) provoked this error
1173     incorrectly, because the \d was being skipped in the check.
1174    
1175     22. The pcretest program now has a new pattern option /B and a command line
1176     option -b, which is equivalent to adding /B to every pattern. This causes
1177     it to show the compiled bytecode, without the additional information that
1178     -d shows. The effect of -d is now the same as -b with -i (and similarly, /D
1179     is the same as /B/I).
1180    
1181     23. A new optimization is now able automatically to treat some sequences such
1182     as a*b as a*+b. More specifically, if something simple (such as a character
1183     or a simple class like \d) has an unlimited quantifier, and is followed by
1184     something that cannot possibly match the quantified thing, the quantifier
1185     is automatically "possessified".
1186    
1187     24. A recursive reference to a subpattern whose number was greater than 39
1188     went wrong under certain circumstances in UTF-8 mode. This bug could also
1189     have affected the operation of pcre_study().
1190    
1191     25. Realized that a little bit of performance could be had by replacing
1192     (c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters.
1193    
1194     26. Timing data from pcretest is now shown to 4 decimal places instead of 3.
1195    
1196     27. Possessive quantifiers such as a++ were previously implemented by turning
1197     them into atomic groups such as ($>a+). Now they have their own opcodes,
1198     which improves performance. This includes the automatically created ones
1199     from 23 above.
1200    
1201     28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a
1202     lookahead was broken if it was not anchored. PCRE was mistakenly expecting
1203     the first matched character to be a colon. This applied both to named and
1204     numbered groups.
1205    
1206     29. The ucpinternal.h header file was missing its idempotency #ifdef.
1207    
1208     30. I was sent a "project" file called libpcre.a.dev which I understand makes
1209     building PCRE on Windows easier, so I have included it in the distribution.
1210    
1211     31. There is now a check in pcretest against a ridiculously large number being
1212     returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G
1213     loop, the loop is abandoned.
1214    
1215     32. Forward references to subpatterns in conditions such as (?(2)...) where
1216     subpattern 2 is defined later cause pcre_compile() to search forwards in
1217     the pattern for the relevant set of parentheses. This search went wrong
1218     when there were unescaped parentheses in a character class, parentheses
1219     escaped with \Q...\E, or parentheses in a #-comment in /x mode.
1220    
1221     33. "Subroutine" calls and backreferences were previously restricted to
1222     referencing subpatterns earlier in the regex. This restriction has now
1223     been removed.
1224    
1225     34. Added a number of extra features that are going to be in Perl 5.10. On the
1226     whole, these are just syntactic alternatives for features that PCRE had
1227     previously implemented using the Python syntax or my own invention. The
1228     other formats are all retained for compatibility.
1229    
1230     (a) Named groups can now be defined as (?<name>...) or (?'name'...) as well
1231     as (?P<name>...). The new forms, as well as being in Perl 5.10, are
1232     also .NET compatible.
1233    
1234     (b) A recursion or subroutine call to a named group can now be defined as
1235     (?&name) as well as (?P>name).
1236    
1237     (c) A backreference to a named group can now be defined as \k<name> or
1238     \k'name' as well as (?P=name). The new forms, as well as being in Perl
1239     5.10, are also .NET compatible.
1240    
1241     (d) A conditional reference to a named group can now use the syntax
1242     (?(<name>) or (?('name') as well as (?(name).
1243    
1244     (e) A "conditional group" of the form (?(DEFINE)...) can be used to define
1245     groups (named and numbered) that are never evaluated inline, but can be
1246     called as "subroutines" from elsewhere. In effect, the DEFINE condition
1247     is always false. There may be only one alternative in such a group.
1248    
1249     (f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well
1250     as the simple (?(R). The condition is true only if the most recent
1251     recursion is that of the given number or name. It does not search out
1252     through the entire recursion stack.
1253    
1254     (g) The escape \gN or \g{N} has been added, where N is a positive or
1255     negative number, specifying an absolute or relative reference.
1256    
1257     35. Tidied to get rid of some further signed/unsigned compiler warnings and
1258     some "unreachable code" warnings.
1259    
1260     36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other
1261     things, this adds five new scripts.
1262    
1263     37. Perl ignores orphaned \E escapes completely. PCRE now does the same.
1264     There were also incompatibilities regarding the handling of \Q..\E inside
1265     character classes, for example with patterns like [\Qa\E-\Qz\E] where the
1266     hyphen was adjacent to \Q or \E. I hope I've cleared all this up now.
1267    
1268     38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group
1269     matches an empty string, and forcibly breaks the loop. There were bugs in
1270     this code in non-simple cases. For a pattern such as ^(a()*)* matched
1271     against aaaa the result was just "a" rather than "aaaa", for example. Two
1272     separate and independent bugs (that affected different cases) have been
1273     fixed.
1274    
1275     39. Refactored the code to abolish the use of different opcodes for small
1276     capturing bracket numbers. This is a tidy that I avoided doing when I
1277     removed the limit on the number of capturing brackets for 3.5 back in 2001.
1278     The new approach is not only tidier, it makes it possible to reduce the
1279     memory needed to fix the previous bug (38).
1280    
1281     40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline
1282     sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when
1283     processing dot, circumflex, or dollar metacharacters, or #-comments in /x
1284     mode.
1285    
1286     41. Add \R to match any Unicode newline sequence, as suggested in the Unicode
1287     report.
1288    
1289     42. Applied patch, originally from Ari Pollak, modified by Google, to allow
1290     copy construction and assignment in the C++ wrapper.
1291    
1292     43. Updated pcregrep to support "--newline=any". In the process, I fixed a
1293     couple of bugs that could have given wrong results in the "--newline=crlf"
1294     case.
1295    
1296     44. Added a number of casts and did some reorganization of signed/unsigned int
1297     variables following suggestions from Dair Grant. Also renamed the variable
1298     "this" as "item" because it is a C++ keyword.
1299    
1300     45. Arranged for dftables to add
1301    
1302     #include "pcre_internal.h"
1303    
1304     to pcre_chartables.c because without it, gcc 4.x may remove the array
1305     definition from the final binary if PCRE is built into a static library and
1306     dead code stripping is activated.
1307    
1308     46. For an unanchored pattern, if a match attempt fails at the start of a
1309     newline sequence, and the newline setting is CRLF or ANY, and the next two
1310     characters are CRLF, advance by two characters instead of one.
1311    
1312    
1313 nigel 91 Version 6.7 04-Jul-06
1314     ---------------------
1315    
1316     1. In order to handle tests when input lines are enormously long, pcretest has
1317     been re-factored so that it automatically extends its buffers when
1318     necessary. The code is crude, but this _is_ just a test program. The
1319     default size has been increased from 32K to 50K.
1320    
1321     2. The code in pcre_study() was using the value of the re argument before
1322     testing it for NULL. (Of course, in any sensible call of the function, it
1323     won't be NULL.)
1324    
1325     3. The memmove() emulation function in pcre_internal.h, which is used on
1326     systems that lack both memmove() and bcopy() - that is, hardly ever -
1327     was missing a "static" storage class specifier.
1328    
1329     4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns
1330     containing an extended class (one that cannot be represented by a bitmap
1331     because it contains high-valued characters or Unicode property items, e.g.
1332     [\pZ]). Almost always one would set UTF-8 mode when processing such a
1333     pattern, but PCRE should not loop if you do not (it no longer does).
1334     [Detail: two cases were found: (a) a repeated subpattern containing an
1335     extended class; (b) a recursive reference to a subpattern that followed a
1336     previous extended class. It wasn't skipping over the extended class
1337     correctly when UTF-8 mode was not set.]
1338    
1339     5. A negated single-character class was not being recognized as fixed-length
1340     in lookbehind assertions such as (?<=[^f]), leading to an incorrect
1341     compile error "lookbehind assertion is not fixed length".
1342    
1343     6. The RunPerlTest auxiliary script was showing an unexpected difference
1344     between PCRE and Perl for UTF-8 tests. It turns out that it is hard to
1345     write a Perl script that can interpret lines of an input file either as
1346     byte characters or as UTF-8, which is what "perltest" was being required to
1347     do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you
1348     can't do is switch easily at run time between having the "use utf8;" pragma
1349     or not. In the end, I fudged it by using the RunPerlTest script to insert
1350     "use utf8;" explicitly for the UTF-8 tests.
1351    
1352     7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at
1353     the end of the subject string, contrary to the documentation and to what
1354     Perl does. This was true of both matching functions. Now it matches only at
1355     the start of the subject and immediately after *internal* newlines.
1356    
1357     8. A call of pcre_fullinfo() from pcretest to get the option bits was passing
1358     a pointer to an int instead of a pointer to an unsigned long int. This
1359     caused problems on 64-bit systems.
1360    
1361     9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another
1362     instance of the 'standard' template library not being so standard".
1363    
1364     10. There was no check on the number of named subpatterns nor the maximum
1365     length of a subpattern name. The product of these values is used to compute
1366     the size of the memory block for a compiled pattern. By supplying a very
1367     long subpattern name and a large number of named subpatterns, the size
1368     computation could be caused to overflow. This is now prevented by limiting
1369     the length of names to 32 characters, and the number of named subpatterns
1370     to 10,000.
1371    
1372     11. Subpatterns that are repeated with specific counts have to be replicated in
1373     the compiled pattern. The size of memory for this was computed from the
1374     length of the subpattern and the repeat count. The latter is limited to
1375     65535, but there was no limit on the former, meaning that integer overflow
1376     could in principle occur. The compiled length of a repeated subpattern is
1377     now limited to 30,000 bytes in order to prevent this.
1378    
1379     12. Added the optional facility to have named substrings with the same name.
1380    
1381     13. Added the ability to use a named substring as a condition, using the
1382     Python syntax: (?(name)yes|no). This overloads (?(R)... and names that
1383     are numbers (not recommended). Forward references are permitted.
1384    
1385     14. Added forward references in named backreferences (if you see what I mean).
1386    
1387     15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the
1388     pattern could run off the end of the subject. For example, the pattern
1389     "(?s)(.{1,5})"8 did this with the subject "ab".
1390    
1391     16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if
1392     PCRE_CASELESS was set when matching characters that were quantified with ?
1393     or *.
1394    
1395     17. A character class other than a single negated character that had a minimum
1396     but no maximum quantifier - for example [ab]{6,} - was not handled
1397     correctly by pce_dfa_exec(). It would match only one character.
1398    
1399     18. A valid (though odd) pattern that looked like a POSIX character
1400     class but used an invalid character after [ (for example [[,abc,]]) caused
1401     pcre_compile() to give the error "Failed: internal error: code overflow" or
1402     in some cases to crash with a glibc free() error. This could even happen if
1403     the pattern terminated after [[ but there just happened to be a sequence of
1404     letters, a binary zero, and a closing ] in the memory that followed.
1405    
1406     19. Perl's treatment of octal escapes in the range \400 to \777 has changed
1407     over the years. Originally (before any Unicode support), just the bottom 8
1408     bits were taken. Thus, for example, \500 really meant \100. Nowadays the
1409     output from "man perlunicode" includes this:
1410    
1411     The regular expression compiler produces polymorphic opcodes. That
1412     is, the pattern adapts to the data and automatically switches to
1413     the Unicode character scheme when presented with Unicode data--or
1414     instead uses a traditional byte scheme when presented with byte
1415     data.
1416    
1417     Sadly, a wide octal escape does not cause a switch, and in a string with
1418     no other multibyte characters, these octal escapes are treated as before.
1419     Thus, in Perl, the pattern /\500/ actually matches \100 but the pattern
1420     /\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a
1421     Unicode string.
1422    
1423     I have not perpetrated such confusion in PCRE. Up till now, it took just
1424     the bottom 8 bits, as in old Perl. I have now made octal escapes with
1425     values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they
1426     translate to the appropriate multibyte character.
1427    
1428     29. Applied some refactoring to reduce the number of warnings from Microsoft
1429     and Borland compilers. This has included removing the fudge introduced
1430     seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused
1431     a warning about an unused variable.
1432    
1433     21. PCRE has not included VT (character 0x0b) in the set of whitespace
1434     characters since release 4.0, because Perl (from release 5.004) does not.
1435     [Or at least, is documented not to: some releases seem to be in conflict
1436     with the documentation.] However, when a pattern was studied with
1437     pcre_study() and all its branches started with \s, PCRE still included VT
1438     as a possible starting character. Of course, this did no harm; it just
1439     caused an unnecessary match attempt.
1440    
1441     22. Removed a now-redundant internal flag bit that recorded the fact that case
1442     dependency changed within the pattern. This was once needed for "required
1443     byte" processing, but is no longer used. This recovers a now-scarce options
1444     bit. Also moved the least significant internal flag bit to the most-
1445     significant bit of the word, which was not previously used (hangover from
1446     the days when it was an int rather than a uint) to free up another bit for
1447     the future.
1448    
1449     23. Added support for CRLF line endings as well as CR and LF. As well as the
1450     default being selectable at build time, it can now be changed at runtime
1451     via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to
1452     specify that it is scanning data with non-default line endings.
1453    
1454     24. Changed the definition of CXXLINK to make it agree with the definition of
1455     LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS.
1456    
1457     25. Applied Ian Taylor's patches to avoid using another stack frame for tail
1458     recursions. This makes a big different to stack usage for some patterns.
1459    
1460     26. If a subpattern containing a named recursion or subroutine reference such
1461     as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of
1462     the space required for the compiled pattern went wrong and gave too small a
1463     value. Depending on the environment, this could lead to "Failed: internal
1464     error: code overflow at offset 49" or "glibc detected double free or
1465     corruption" errors.
1466    
1467     27. Applied patches from Google (a) to support the new newline modes and (b) to
1468     advance over multibyte UTF-8 characters in GlobalReplace.
1469    
1470     28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a
1471     difference for some implementation of PCRE in some Windows version.
1472    
1473     29. Added some extra testing facilities to pcretest:
1474    
1475     \q<number> in a data line sets the "match limit" value
1476     \Q<number> in a data line sets the "match recursion limt" value
1477     -S <number> sets the stack size, where <number> is in megabytes
1478    
1479     The -S option isn't available for Windows.
1480    
1481    
1482 nigel 89 Version 6.6 06-Feb-06
1483     ---------------------
1484    
1485     1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined
1486     in pcreposix.h. I have copied the definition from pcre.h.
1487    
1488     2. Change 25 for 6.5 broke compilation in a build directory out-of-tree
1489     because pcre.h is no longer a built file.
1490    
1491     3. Added Jeff Friedl's additional debugging patches to pcregrep. These are
1492     not normally included in the compiled code.
1493    
1494    
1495 nigel 87 Version 6.5 01-Feb-06
1496     ---------------------
1497    
1498     1. When using the partial match feature with pcre_dfa_exec(), it was not
1499     anchoring the second and subsequent partial matches at the new starting
1500     point. This could lead to incorrect results. For example, with the pattern
1501     /1234/, partially matching against "123" and then "a4" gave a match.
1502    
1503     2. Changes to pcregrep:
1504    
1505     (a) All non-match returns from pcre_exec() were being treated as failures
1506     to match the line. Now, unless the error is PCRE_ERROR_NOMATCH, an
1507     error message is output. Some extra information is given for the
1508     PCRE_ERROR_MATCHLIMIT and PCRE_ERROR_RECURSIONLIMIT errors, which are
1509     probably the only errors that are likely to be caused by users (by
1510     specifying a regex that has nested indefinite repeats, for instance).
1511     If there are more than 20 of these errors, pcregrep is abandoned.
1512    
1513     (b) A binary zero was treated as data while matching, but terminated the
1514     output line if it was written out. This has been fixed: binary zeroes
1515     are now no different to any other data bytes.
1516    
1517     (c) Whichever of the LC_ALL or LC_CTYPE environment variables is set is
1518     used to set a locale for matching. The --locale=xxxx long option has
1519     been added (no short equivalent) to specify a locale explicitly on the
1520     pcregrep command, overriding the environment variables.
1521    
1522     (d) When -B was used with -n, some line numbers in the output were one less
1523     than they should have been.
1524    
1525     (e) Added the -o (--only-matching) option.
1526    
1527     (f) If -A or -C was used with -c (count only), some lines of context were
1528     accidentally printed for the final match.
1529    
1530     (g) Added the -H (--with-filename) option.
1531    
1532     (h) The combination of options -rh failed to suppress file names for files
1533     that were found from directory arguments.
1534    
1535     (i) Added the -D (--devices) and -d (--directories) options.
1536    
1537     (j) Added the -F (--fixed-strings) option.
1538    
1539     (k) Allow "-" to be used as a file name for -f as well as for a data file.
1540    
1541     (l) Added the --colo(u)r option.
1542    
1543     (m) Added Jeffrey Friedl's -S testing option, but within #ifdefs so that it
1544     is not present by default.
1545    
1546     3. A nasty bug was discovered in the handling of recursive patterns, that is,
1547     items such as (?R) or (?1), when the recursion could match a number of
1548     alternatives. If it matched one of the alternatives, but subsequently,
1549     outside the recursion, there was a failure, the code tried to back up into
1550     the recursion. However, because of the way PCRE is implemented, this is not
1551     possible, and the result was an incorrect result from the match.
1552    
1553     In order to prevent this happening, the specification of recursion has
1554     been changed so that all such subpatterns are automatically treated as
1555     atomic groups. Thus, for example, (?R) is treated as if it were (?>(?R)).
1556    
1557     4. I had overlooked the fact that, in some locales, there are characters for
1558     which isalpha() is true but neither isupper() nor islower() are true. In
1559     the fr_FR locale, for instance, the \xAA and \xBA characters (ordmasculine
1560     and ordfeminine) are like this. This affected the treatment of \w and \W
1561     when they appeared in character classes, but not when they appeared outside
1562     a character class. The bit map for "word" characters is now created
1563     separately from the results of isalnum() instead of just taking it from the
1564     upper, lower, and digit maps. (Plus the underscore character, of course.)
1565    
1566     5. The above bug also affected the handling of POSIX character classes such as
1567     [[:alpha:]] and [[:alnum:]]. These do not have their own bit maps in PCRE's
1568     permanent tables. Instead, the bit maps for such a class were previously
1569     created as the appropriate unions of the upper, lower, and digit bitmaps.
1570     Now they are created by subtraction from the [[:word:]] class, which has
1571     its own bitmap.
1572    
1573     6. The [[:blank:]] character class matches horizontal, but not vertical space.
1574     It is created by subtracting the vertical space characters (\x09, \x0a,
1575     \x0b, \x0c) from the [[:space:]] bitmap. Previously, however, the
1576     subtraction was done in the overall bitmap for a character class, meaning
1577     that a class such as [\x0c[:blank:]] was incorrect because \x0c would not
1578     be recognized. This bug has been fixed.
1579    
1580     7. Patches from the folks at Google:
1581    
1582     (a) pcrecpp.cc: "to handle a corner case that may or may not happen in
1583     real life, but is still worth protecting against".
1584    
1585     (b) pcrecpp.cc: "corrects a bug when negative radixes are used with
1586     regular expressions".
1587    
1588     (c) pcre_scanner.cc: avoid use of std::count() because not all systems
1589     have it.
1590    
1591     (d) Split off pcrecpparg.h from pcrecpp.h and had the former built by
1592     "configure" and the latter not, in order to fix a problem somebody had
1593     with compiling the Arg class on HP-UX.
1594    
1595     (e) Improve the error-handling of the C++ wrapper a little bit.
1596    
1597     (f) New tests for checking recursion limiting.
1598    
1599     8. The pcre_memmove() function, which is used only if the environment does not
1600     have a standard memmove() function (and is therefore rarely compiled),
1601     contained two bugs: (a) use of int instead of size_t, and (b) it was not
1602     returning a result (though PCRE never actually uses the result).
1603    
1604     9. In the POSIX regexec() interface, if nmatch is specified as a ridiculously
1605     large number - greater than INT_MAX/(3*sizeof(int)) - REG_ESPACE is
1606     returned instead of calling malloc() with an overflowing number that would
1607     most likely cause subsequent chaos.
1608    
1609     10. The debugging option of pcretest was not showing the NO_AUTO_CAPTURE flag.
1610    
1611     11. The POSIX flag REG_NOSUB is now supported. When a pattern that was compiled
1612     with this option is matched, the nmatch and pmatch options of regexec() are
1613     ignored.
1614    
1615     12. Added REG_UTF8 to the POSIX interface. This is not defined by POSIX, but is
1616     provided in case anyone wants to the the POSIX interface with UTF-8
1617     strings.
1618    
1619     13. Added CXXLDFLAGS to the Makefile parameters to provide settings only on the
1620     C++ linking (needed for some HP-UX environments).
1621    
1622     14. Avoid compiler warnings in get_ucpname() when compiled without UCP support
1623     (unused parameter) and in the pcre_printint() function (omitted "default"
1624     switch label when the default is to do nothing).
1625    
1626     15. Added some code to make it possible, when PCRE is compiled as a C++
1627     library, to replace subject pointers for pcre_exec() with a smart pointer
1628     class, thus making it possible to process discontinuous strings.
1629    
1630     16. The two macros PCRE_EXPORT and PCRE_DATA_SCOPE are confusing, and perform
1631     much the same function. They were added by different people who were trying
1632     to make PCRE easy to compile on non-Unix systems. It has been suggested
1633     that PCRE_EXPORT be abolished now that there is more automatic apparatus
1634     for compiling on Windows systems. I have therefore replaced it with
1635     PCRE_DATA_SCOPE. This is set automatically for Windows; if not set it
1636     defaults to "extern" for C or "extern C" for C++, which works fine on
1637     Unix-like systems. It is now possible to override the value of PCRE_DATA_
1638     SCOPE with something explicit in config.h. In addition:
1639    
1640     (a) pcreposix.h still had just "extern" instead of either of these macros;
1641     I have replaced it with PCRE_DATA_SCOPE.
1642    
1643     (b) Functions such as _pcre_xclass(), which are internal to the library,
1644     but external in the C sense, all had PCRE_EXPORT in their definitions.
1645     This is apparently wrong for the Windows case, so I have removed it.
1646     (It makes no difference on Unix-like systems.)
1647    
1648     17. Added a new limit, MATCH_LIMIT_RECURSION, which limits the depth of nesting
1649     of recursive calls to match(). This is different to MATCH_LIMIT because
1650     that limits the total number of calls to match(), not all of which increase
1651     the depth of recursion. Limiting the recursion depth limits the amount of
1652     stack (or heap if NO_RECURSE is set) that is used. The default can be set
1653     when PCRE is compiled, and changed at run time. A patch from Google adds
1654     this functionality to the C++ interface.
1655    
1656     18. Changes to the handling of Unicode character properties:
1657    
1658     (a) Updated the table to Unicode 4.1.0.
1659    
1660     (b) Recognize characters that are not in the table as "Cn" (undefined).
1661    
1662     (c) I revised the way the table is implemented to a much improved format
1663     which includes recognition of ranges. It now supports the ranges that
1664     are defined in UnicodeData.txt, and it also amalgamates other
1665     characters into ranges. This has reduced the number of entries in the
1666     table from around 16,000 to around 3,000, thus reducing its size
1667     considerably. I realized I did not need to use a tree structure after
1668     all - a binary chop search is just as efficient. Having reduced the
1669     number of entries, I extended their size from 6 bytes to 8 bytes to
1670     allow for more data.
1671    
1672     (d) Added support for Unicode script names via properties such as \p{Han}.
1673    
1674     19. In UTF-8 mode, a backslash followed by a non-Ascii character was not
1675     matching that character.
1676    
1677     20. When matching a repeated Unicode property with a minimum greater than zero,
1678     (for example \pL{2,}), PCRE could look past the end of the subject if it
1679     reached it while seeking the minimum number of characters. This could
1680     happen only if some of the characters were more than one byte long, because
1681     there is a check for at least the minimum number of bytes.
1682    
1683     21. Refactored the implementation of \p and \P so as to be more general, to
1684     allow for more different types of property in future. This has changed the
1685     compiled form incompatibly. Anybody with saved compiled patterns that use
1686     \p or \P will have to recompile them.
1687    
1688     22. Added "Any" and "L&" to the supported property types.
1689    
1690     23. Recognize \x{...} as a code point specifier, even when not in UTF-8 mode,
1691     but give a compile time error if the value is greater than 0xff.
1692    
1693     24. The man pages for pcrepartial, pcreprecompile, and pcre_compile2 were
1694     accidentally not being installed or uninstalled.
1695    
1696     25. The pcre.h file was built from pcre.h.in, but the only changes that were
1697     made were to insert the current release number. This seemed silly, because
1698     it made things harder for people building PCRE on systems that don't run
1699     "configure". I have turned pcre.h into a distributed file, no longer built
1700     by "configure", with the version identification directly included. There is
1701     no longer a pcre.h.in file.
1702    
1703     However, this change necessitated a change to the pcre-config script as
1704     well. It is built from pcre-config.in, and one of the substitutions was the
1705     release number. I have updated configure.ac so that ./configure now finds
1706     the release number by grepping pcre.h.
1707    
1708     26. Added the ability to run the tests under valgrind.
1709    
1710    
1711 nigel 85 Version 6.4 05-Sep-05
1712     ---------------------
1713    
1714     1. Change 6.0/10/(l) to pcregrep introduced a bug that caused separator lines
1715     "--" to be printed when multiple files were scanned, even when none of the
1716     -A, -B, or -C options were used. This is not compatible with Gnu grep, so I
1717     consider it to be a bug, and have restored the previous behaviour.
1718    
1719     2. A couple of code tidies to get rid of compiler warnings.
1720    
1721     3. The pcretest program used to cheat by referring to symbols in the library
1722     whose names begin with _pcre_. These are internal symbols that are not
1723     really supposed to be visible externally, and in some environments it is
1724     possible to suppress them. The cheating is now confined to including
1725     certain files from the library's source, which is a bit cleaner.
1726    
1727     4. Renamed pcre.in as pcre.h.in to go with pcrecpp.h.in; it also makes the
1728     file's purpose clearer.
1729    
1730     5. Reorganized pcre_ucp_findchar().
1731    
1732    
1733 nigel 83 Version 6.3 15-Aug-05
1734     ---------------------
1735    
1736     1. The file libpcre.pc.in did not have general read permission in the tarball.
1737    
1738     2. There were some problems when building without C++ support:
1739    
1740     (a) If C++ support was not built, "make install" and "make test" still
1741     tried to test it.
1742    
1743     (b) There were problems when the value of CXX was explicitly set. Some
1744     changes have been made to try to fix these, and ...
1745    
1746     (c) --disable-cpp can now be used to explicitly disable C++ support.
1747    
1748     (d) The use of @CPP_OBJ@ directly caused a blank line preceded by a
1749     backslash in a target when C++ was disabled. This confuses some
1750     versions of "make", apparently. Using an intermediate variable solves
1751     this. (Same for CPP_LOBJ.)
1752    
1753     3. $(LINK_FOR_BUILD) now includes $(CFLAGS_FOR_BUILD) and $(LINK)
1754     (non-Windows) now includes $(CFLAGS) because these flags are sometimes
1755     necessary on certain architectures.
1756    
1757     4. Added a setting of -export-symbols-regex to the link command to remove
1758     those symbols that are exported in the C sense, but actually are local
1759     within the library, and not documented. Their names all begin with
1760     "_pcre_". This is not a perfect job, because (a) we have to except some
1761     symbols that pcretest ("illegally") uses, and (b) the facility isn't always
1762     available (and never for static libraries). I have made a note to try to
1763     find a way round (a) in the future.
1764    
1765    
1766 nigel 81 Version 6.2 01-Aug-05
1767     ---------------------
1768    
1769     1. There was no test for integer overflow of quantifier values. A construction
1770     such as {1111111111111111} would give undefined results. What is worse, if
1771     a minimum quantifier for a parenthesized subpattern overflowed and became
1772     negative, the calculation of the memory size went wrong. This could have
1773     led to memory overwriting.
1774    
1775     2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
1776    
1777     3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
1778     operating environments where this matters.
1779    
1780     4. Applied Giuseppe Maxia's patch to add additional features for controlling
1781     PCRE options from within the C++ wrapper.
1782    
1783     5. Named capturing subpatterns were not being correctly counted when a pattern
1784     was compiled. This caused two problems: (a) If there were more than 100
1785     such subpatterns, the calculation of the memory needed for the whole
1786     compiled pattern went wrong, leading to an overflow error. (b) Numerical
1787     back references of the form \12, where the number was greater than 9, were
1788     not recognized as back references, even though there were sufficient
1789     previous subpatterns.
1790    
1791     6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
1792     versions of gcc, e.g. 2.95.4.
1793    
1794    
1795 nigel 79 Version 6.1 21-Jun-05
1796     ---------------------
1797    
1798     1. There was one reference to the variable "posix" in pcretest.c that was not
1799     surrounded by "#if !defined NOPOSIX".
1800    
1801     2. Make it possible to compile pcretest without DFA support, UTF8 support, or
1802     the cross-check on the old pcre_info() function, for the benefit of the
1803     cut-down version of PCRE that is currently imported into Exim.
1804    
1805     3. A (silly) pattern starting with (?i)(?-i) caused an internal space
1806     allocation error. I've done the easy fix, which wastes 2 bytes for sensible
1807     patterns that start (?i) but I don't think that matters. The use of (?i) is
1808     just an example; this all applies to the other options as well.
1809    
1810     4. Since libtool seems to echo the compile commands it is issuing, the output
1811     from "make" can be reduced a bit by putting "@" in front of each libtool
1812     compile command.
1813    
1814     5. Patch from the folks at Google for configure.in to be a bit more thorough
1815     in checking for a suitable C++ installation before trying to compile the
1816     C++ stuff. This should fix a reported problem when a compiler was present,
1817     but no suitable headers.
1818    
1819     6. The man pages all had just "PCRE" as their title. I have changed them to
1820     be the relevant file name. I have also arranged that these names are
1821     retained in the file doc/pcre.txt, which is a concatenation in text format
1822     of all the man pages except the little individual ones for each function.
1823    
1824     7. The NON-UNIX-USE file had not been updated for the different set of source
1825     files that come with release 6. I also added a few comments about the C++
1826     wrapper.
1827    
1828    
1829 nigel 77 Version 6.0 07-Jun-05
1830     ---------------------
1831    
1832     1. Some minor internal re-organization to help with my DFA experiments.
1833    
1834     2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
1835     didn't matter for the library itself when fully configured, but did matter
1836     when compiling without UCP support, or within Exim, where the ucp files are
1837     not imported.
1838    
1839     3. Refactoring of the library code to split up the various functions into
1840     different source modules. The addition of the new DFA matching code (see
1841     below) to a single monolithic source would have made it really too
1842     unwieldy, quite apart from causing all the code to be include in a
1843     statically linked application, when only some functions are used. This is
1844     relevant even without the DFA addition now that patterns can be compiled in
1845     one application and matched in another.
1846    
1847     The downside of splitting up is that there have to be some external
1848     functions and data tables that are used internally in different modules of
1849     the library but which are not part of the API. These have all had their
1850     names changed to start with "_pcre_" so that they are unlikely to clash
1851     with other external names.
1852    
1853     4. Added an alternate matching function, pcre_dfa_exec(), which matches using
1854     a different (DFA) algorithm. Although it is slower than the original
1855     function, it does have some advantages for certain types of matching
1856     problem.
1857    
1858     5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
1859     including restarting after a partial match.
1860    
1861     6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
1862     defined when compiling for Windows was sent to me. I have put it into the
1863     code, though I have no means of testing or verifying it.
1864    
1865     7. Added the pcre_refcount() auxiliary function.
1866    
1867     8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
1868     match before or at the first newline in the subject string. In pcretest,
1869     the /f option on a pattern can be used to set this.
1870    
1871     9. A repeated \w when used in UTF-8 mode with characters greater than 256
1872     would behave wrongly. This has been present in PCRE since release 4.0.
1873    
1874     10. A number of changes to the pcregrep command:
1875    
1876     (a) Refactored how -x works; insert ^(...)$ instead of setting
1877     PCRE_ANCHORED and checking the length, in preparation for adding
1878     something similar for -w.
1879    
1880     (b) Added the -w (match as a word) option.
1881    
1882     (c) Refactored the way lines are read and buffered so as to have more
1883     than one at a time available.
1884    
1885     (d) Implemented a pcregrep test script.
1886    
1887     (e) Added the -M (multiline match) option. This allows patterns to match
1888     over several lines of the subject. The buffering ensures that at least
1889     8K, or the rest of the document (whichever is the shorter) is available
1890     for matching (and similarly the previous 8K for lookbehind assertions).
1891    
1892     (f) Changed the --help output so that it now says
1893    
1894     -w, --word-regex(p)
1895    
1896     instead of two lines, one with "regex" and the other with "regexp"
1897     because that confused at least one person since the short forms are the
1898     same. (This required a bit of code, as the output is generated
1899     automatically from a table. It wasn't just a text change.)
1900    
1901     (g) -- can be used to terminate pcregrep options if the next thing isn't an
1902     option but starts with a hyphen. Could be a pattern or a path name
1903     starting with a hyphen, for instance.
1904    
1905     (h) "-" can be given as a file name to represent stdin.
1906    
1907     (i) When file names are being printed, "(standard input)" is used for
1908     the standard input, for compatibility with GNU grep. Previously
1909     "<stdin>" was used.
1910    
1911     (j) The option --label=xxx can be used to supply a name to be used for
1912     stdin when file names are being printed. There is no short form.
1913    
1914     (k) Re-factored the options decoding logic because we are going to add
1915     two more options that take data. Such options can now be given in four
1916     different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
1917    
1918     (l) Added the -A, -B, and -C options for requesting that lines of context
1919     around matches be printed.
1920    
1921     (m) Added the -L option to print the names of files that do not contain
1922     any matching lines, that is, the complement of -l.
1923    
1924     (n) The return code is 2 if any file cannot be opened, but pcregrep does
1925     continue to scan other files.
1926    
1927     (o) The -s option was incorrectly implemented. For compatibility with other
1928     greps, it now suppresses the error message for a non-existent or non-
1929     accessible file (but not the return code). There is a new option called
1930     -q that suppresses the output of matching lines, which was what -s was
1931     previously doing.
1932    
1933     (p) Added --include and --exclude options to specify files for inclusion
1934     and exclusion when recursing.
1935    
1936     11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
1937     Hopefully, it now does.
1938    
1939     12. Missing cast in pcre_study().
1940    
1941     13. Added an "uninstall" target to the makefile.
1942    
1943     14. Replaced "extern" in the function prototypes in Makefile.in with
1944     "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
1945     world, but is set differently for Windows.
1946    
1947     15. Added a second compiling function called pcre_compile2(). The only
1948     difference is that it has an extra argument, which is a pointer to an
1949     integer error code. When there is a compile-time failure, this is set
1950     non-zero, in addition to the error test pointer being set to point to an
1951     error message. The new argument may be NULL if no error number is required
1952     (but then you may as well call pcre_compile(), which is now just a
1953     wrapper). This facility is provided because some applications need a
1954     numeric error indication, but it has also enabled me to tidy up the way
1955     compile-time errors are handled in the POSIX wrapper.
1956    
1957     16. Added VPATH=.libs to the makefile; this should help when building with one
1958     prefix path and installing with another. (Or so I'm told by someone who
1959     knows more about this stuff than I do.)
1960    
1961     17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
1962     passes PCRE_DOTALL to the pcre_compile() function, making the "." character
1963     match everything, including newlines. This is not POSIX-compatible, but
1964     somebody wanted the feature. From pcretest it can be activated by using
1965     both the P and the s flags.
1966    
1967     18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
1968    
1969     19. libpcre.pc was being incorrectly installed as executable.
1970    
1971     20. A couple of places in pcretest check for end-of-line by looking for '\n';
1972     it now also looks for '\r' so that it will work unmodified on Windows.
1973    
1974     21. Added Google's contributed C++ wrapper to the distribution.
1975    
1976     22. Added some untidy missing memory free() calls in pcretest, to keep
1977     Electric Fence happy when testing.
1978    
1979    
1980    
1981 nigel 75 Version 5.0 13-Sep-04
1982     ---------------------
1983    
1984     1. Internal change: literal characters are no longer packed up into items
1985     containing multiple characters in a single byte-string. Each character
1986     is now matched using a separate opcode. However, there may be more than one
1987     byte in the character in UTF-8 mode.
1988    
1989     2. The pcre_callout_block structure has two new fields: pattern_position and
1990     next_item_length. These contain the offset in the pattern to the next match
1991     item, and its length, respectively.
1992    
1993     3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
1994     insertion of callouts before each pattern item. Added the /C option to
1995     pcretest to make use of this.
1996    
1997     4. On the advice of a Windows user, the lines
1998    
1999     #if defined(_WIN32) || defined(WIN32)
2000     _setmode( _fileno( stdout ), 0x8000 );
2001     #endif /* defined(_WIN32) || defined(WIN32) */
2002    
2003     have been added to the source of pcretest. This apparently does useful
2004     magic in relation to line terminators.
2005    
2006     5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
2007     for the benefit of those environments where the "b" makes a difference.
2008    
2009     6. The icc compiler has the same options as gcc, but "configure" doesn't seem
2010     to know about it. I have put a hack into configure.in that adds in code
2011     to set GCC=yes if CC=icc. This seems to end up at a point in the
2012     generated configure script that is early enough to affect the setting of
2013     compiler options, which is what is needed, but I have no means of testing
2014     whether it really works. (The user who reported this had patched the
2015     generated configure script, which of course I cannot do.)
2016    
2017     LATER: After change 22 below (new libtool files), the configure script
2018     seems to know about icc (and also ecc). Therefore, I have commented out
2019     this hack in configure.in.
2020    
2021     7. Added support for pkg-config (2 patches were sent in).
2022    
2023     8. Negated POSIX character classes that used a combination of internal tables
2024     were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
2025     [[:^ascii]]. Typically, they would match almost any characters. The other
2026     POSIX classes were not broken in this way.
2027    
2028     9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
2029     to find the match, as PCRE was deluded into thinking that the match had to
2030     start at the start point or following a newline. The same bug applied to
2031     patterns with negative forward assertions or any backward assertions
2032     preceding ".*" at the start, unless the pattern required a fixed first
2033     character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
2034    
2035     10. In UTF-8 mode, when moving forwards in the subject after a failed match
2036     starting at the last subject character, bytes beyond the end of the subject
2037     string were read.
2038    
2039     11. Renamed the variable "class" as "classbits" to make life easier for C++
2040     users. (Previously there was a macro definition, but it apparently wasn't
2041     enough.)
2042    
2043     12. Added the new field "tables" to the extra data so that tables can be passed
2044     in at exec time, or the internal tables can be re-selected. This allows
2045     a compiled regex to be saved and re-used at a later time by a different
2046     program that might have everything at different addresses.
2047    
2048     13. Modified the pcre-config script so that, when run on Solaris, it shows a
2049     -R library as well as a -L library.
2050    
2051     14. The debugging options of pcretest (-d on the command line or D on a
2052     pattern) showed incorrect output for anything following an extended class
2053     that contained multibyte characters and which was followed by a quantifier.
2054    
2055     15. Added optional support for general category Unicode character properties
2056     via the \p, \P, and \X escapes. Unicode property support implies UTF-8
2057     support. It adds about 90K to the size of the library. The meanings of the
2058     inbuilt class escapes such as \d and \s have NOT been changed.
2059    
2060     16. Updated pcredemo.c to include calls to free() to release the memory for the
2061     compiled pattern.
2062    
2063     17. The generated file chartables.c was being created in the source directory
2064     instead of in the building directory. This caused the build to fail if the
2065     source directory was different from the building directory, and was
2066     read-only.
2067    
2068     18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
2069     file. No doubt somebody will tell me if they don't make sense... Also added
2070     Dan Mooney's comments about building on OpenVMS.
2071    
2072     19. Added support for partial matching via the PCRE_PARTIAL option for
2073     pcre_exec() and the \P data escape in pcretest.
2074    
2075     20. Extended pcretest with 3 new pattern features:
2076    
2077     (i) A pattern option of the form ">rest-of-line" causes pcretest to
2078     write the compiled pattern to the file whose name is "rest-of-line".
2079     This is a straight binary dump of the data, with the saved pointer to
2080     the character tables forced to be NULL. The study data, if any, is
2081     written too. After writing, pcretest reads a new pattern.
2082    
2083     (ii) If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
2084     compiled pattern from the given file. There must not be any
2085     occurrences of "<" in the file name (pretty unlikely); if there are,
2086     pcretest will instead treat the initial "<" as a pattern delimiter.
2087     After reading in the pattern, pcretest goes on to read data lines as
2088     usual.
2089    
2090     (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
2091     and 16-bit fields in a compiled pattern, to simulate a pattern that
2092     was compiled on a host of opposite endianness.
2093    
2094     21. The pcre-exec() function can now cope with patterns that were compiled on
2095     hosts of opposite endianness, with this restriction:
2096    
2097     As for any compiled expression that is saved and used later, the tables
2098     pointer field cannot be preserved; the extra_data field in the arguments
2099     to pcre_exec() should be used to pass in a tables address if a value
2100     other than the default internal tables were used at compile time.
2101    
2102     22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
2103     now diagnosed as an error. Previously, most of the time, a negative number
2104     would have been treated as zero, but if in addition "ovector" was passed as
2105     NULL, a crash could occur.
2106    
2107     23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
2108     new versions from the libtool 1.5 distribution (the last one is a copy of
2109     a file called libtool.m4). This seems to have fixed the need to patch
2110     "configure" to support Darwin 1.3 (which I used to do). However, I still
2111     had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
2112     workstation).
2113    
2114     24. Changed the PCRE licence to be the more standard "BSD" licence.
2115    
2116    
2117 nigel 73 Version 4.5 01-Dec-03
2118     ---------------------
2119    
2120     1. There has been some re-arrangement of the code for the match() function so
2121     that it can be compiled in a version that does not call itself recursively.
2122     Instead, it keeps those local variables that need separate instances for
2123     each "recursion" in a frame on the heap, and gets/frees frames whenever it
2124     needs to "recurse". Keeping track of where control must go is done by means
2125     of setjmp/longjmp. The whole thing is implemented by a set of macros that
2126     hide most of the details from the main code, and operates only if
2127     NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
2128     "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
2129     operating.
2130    
2131     To make it easier for callers to provide specially tailored get/free
2132     functions for this usage, two new functions, pcre_stack_malloc, and
2133     pcre_stack_free, are used. They are always called in strict stacking order,
2134     and the size of block requested is always the same.
2135    
2136     The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
2137     PCRE has been compiled to use the stack or the heap for recursion. The
2138     -C option of pcretest uses this to show which version is compiled.
2139    
2140     A new data escape \S, is added to pcretest; it causes the amounts of store
2141     obtained and freed by both kinds of malloc/free at match time to be added
2142     to the output.
2143    
2144     2. Changed the locale test to use "fr_FR" instead of "fr" because that's
2145     what's available on my current Linux desktop machine.
2146    
2147     3. When matching a UTF-8 string, the test for a valid string at the start has
2148     been extended. If start_offset is not zero, PCRE now checks that it points
2149     to a byte that is the start of a UTF-8 character. If not, it returns
2150     PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
2151     this is necessary because there may be backward assertions in the pattern.
2152     When matching the same subject several times, it may save resources to use
2153     PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
2154    
2155     4. The code for checking the validity of UTF-8 strings has been tightened so
2156     that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
2157     containing "overlong sequences".
2158    
2159     5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
2160     I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
2161     should have been "&", but it just so happened that all the cases this let
2162     through by mistake were picked up later in the function.
2163    
2164     6. I had used a variable called "isblank" - this is a C99 function, causing
2165     some compilers to warn. To avoid this, I renamed it (as "blankclass").
2166    
2167     7. Cosmetic: (a) only output another newline at the end of pcretest if it is
2168     prompting; (b) run "./pcretest /dev/null" at the start of the test script
2169     so the version is shown; (c) stop "make test" echoing "./RunTest".
2170    
2171     8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
2172    
2173     9. The prototype for memmove() for systems that don't have it was using
2174     size_t, but the inclusion of the header that defines size_t was later. I've
2175     moved the #includes for the C headers earlier to avoid this.
2176    
2177     10. Added some adjustments to the code to make it easier to compiler on certain
2178     special systems:
2179    
2180     (a) Some "const" qualifiers were missing.
2181     (b) Added the macro EXPORT before all exported functions; by default this
2182     is defined to be empty.
2183     (c) Changed the dftables auxiliary program (that builds chartables.c) so
2184     that it reads its output file name as an argument instead of writing
2185     to the standard output and assuming this can be redirected.
2186    
2187     11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
2188     class containing characters with values greater than 255, PCRE compilation
2189     went into a loop.
2190    
2191     12. A recursive reference to a subpattern that was within another subpattern
2192     that had a minimum quantifier of zero caused PCRE to crash. For example,
2193     (x(y(?2))z)? provoked this bug with a subject that got as far as the
2194     recursion. If the recursively-called subpattern itself had a zero repeat,
2195     that was OK.
2196    
2197     13. In pcretest, the buffer for reading a data line was set at 30K, but the
2198     buffer into which it was copied (for escape processing) was still set at
2199     1024, so long lines caused crashes.
2200    
2201     14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
2202     "internal error: code overflow...". This applied to any character class
2203     that was followed by a possessive quantifier.
2204    
2205     15. Modified the Makefile to add libpcre.la as a prerequisite for
2206     libpcreposix.la because I was told this is needed for a parallel build to
2207     work.
2208    
2209     16. If a pattern that contained .* following optional items at the start was
2210     studied, the wrong optimizing data was generated, leading to matching
2211     errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
2212     matching string must start with a or b or c. The correct conclusion for
2213     this pattern is that a match can start with any character.
2214    
2215    
2216 nigel 71 Version 4.4 13-Aug-03
2217     ---------------------
2218    
2219     1. In UTF-8 mode, a character class containing characters with values between
2220     127 and 255 was not handled correctly if the compiled pattern was studied.
2221     In fixing this, I have also improved the studying algorithm for such
2222     classes (slightly).
2223    
2224     2. Three internal functions had redundant arguments passed to them. Removal
2225     might give a very teeny performance improvement.
2226    
2227     3. Documentation bug: the value of the capture_top field in a callout is *one
2228     more than* the number of the hightest numbered captured substring.
2229    
2230     4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
2231     in incorrectly linking with a previously installed version. They now link
2232     explicitly with libpcre.la.
2233    
2234     5. configure.in no longer needs to recognize Cygwin specially.
2235    
2236     6. A problem in pcre.in for Windows platforms is fixed.
2237    
2238     7. If a pattern was successfully studied, and the -d (or /D) flag was given to
2239     pcretest, it used to include the size of the study block as part of its
2240     output. Unfortunately, the structure contains a field that has a different
2241     size on different hardware architectures. This meant that the tests that
2242     showed this size failed. As the block is currently always of a fixed size,
2243     this information isn't actually particularly useful in pcretest output, so
2244     I have just removed it.
2245    
2246     8. Three pre-processor statements accidentally did not start in column 1.
2247     Sadly, there are *still* compilers around that complain, even though
2248     standard C has not required this for well over a decade. Sigh.
2249    
2250     9. In pcretest, the code for checking callouts passed small integers in the
2251     callout_data field, which is a void * field. However, some picky compilers
2252     complained about the casts involved for this on 64-bit systems. Now
2253     pcretest passes the address of the small integer instead, which should get
2254     rid of the warnings.
2255    
2256     10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
2257     both compile and run time, and gives an error if an invalid UTF-8 sequence
2258     is found. There is a option for disabling this check in cases where the
2259     string is known to be correct and/or the maximum performance is wanted.
2260    
2261     11. In response to a bug report, I changed one line in Makefile.in from
2262    
2263     -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
2264     to
2265     -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
2266    
2267     to look similar to other lines, but I have no way of telling whether this
2268     is the right thing to do, as I do not use Windows. No doubt I'll get told
2269     if it's wrong...
2270    
2271    
2272 nigel 69 Version 4.3 21-May-03
2273     ---------------------
2274    
2275     1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
2276     Makefile.
2277    
2278     2. Some refactoring to improve the quality of the code:
2279    
2280     (i) The utf8_table... variables are now declared "const".
2281    
2282     (ii) The code for \cx, which used the "case flipping" table to upper case
2283     lower case letters, now just substracts 32. This is ASCII-specific,
2284     but the whole concept of \cx is ASCII-specific, so it seems
2285     reasonable.
2286    
2287     (iii) PCRE was using its character types table to recognize decimal and
2288     hexadecimal digits in the pattern. This is silly, because it handles
2289     only 0-9, a-f, and A-F, but the character types table is locale-
2290     specific, which means strange things might happen. A private
2291     table is now used for this - though it costs 256 bytes, a table is
2292     much faster than multiple explicit tests. Of course, the standard
2293     character types table is still used for matching digits in subject
2294     strings against \d.
2295    
2296     (iv) Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
2297     ending in _t are). So I've renamed it as ESC_tee.
2298    
2299     3. The first argument for regexec() in the POSIX wrapper should have been
2300     defined as "const".
2301    
2302     4. Changed pcretest to use malloc() for its buffers so that they can be
2303     Electric Fenced for debugging.
2304    
2305     5. There were several places in the code where, in UTF-8 mode, PCRE would try
2306     to read one or more bytes before the start of the subject string. Often this
2307     had no effect on PCRE's behaviour, but in some circumstances it could
2308     provoke a segmentation fault.
2309    
2310     6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
2311     to try to read one or more bytes before the start of the subject string.
2312    
2313     7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
2314     UTF-8 support could misbehave in various ways if the subject string
2315     contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
2316     area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
2317     back over UTF-8 characters.)
2318    
2319    
2320 nigel 67 Version 4.2 14-Apr-03
2321     ---------------------
2322    
2323     1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.
2324    
2325     2. Changes to the building process, supplied by Ronald Landheer-Cieslak
2326     [ON_WINDOWS]: new variable, "#" on non-Windows platforms
2327     [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
2328     [WIN_PREFIX]: new variable, "cyg" for Cygwin
2329     * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
2330     and BUILD_EXEEXT
2331     Note: automatic setting of the BUILD variables is not yet working
2332     set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
2333     compile-time but not at link-time
2334     [LINK]: use for linking executables only
2335     make different versions for Windows and non-Windows
2336     [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
2337     libraries
2338     [LINK_FOR_BUILD]: new variable
2339     [OBJEXT]: use throughout
2340     [EXEEXT]: use throughout
2341     <winshared>: new target
2342     <wininstall>: new target
2343     <dftables.o>: use native compiler
2344     <dftables>: use native linker
2345     <install>: handle Windows platform correctly
2346     <clean>: ditto
2347     <check>: ditto
2348     copy DLL to top builddir before testing
2349    
2350     As part of these changes, -no-undefined was removed again. This was reported
2351     to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
2352     in any case.
2353    
2354     3. Some tidies to get rid of compiler warnings:
2355    
2356     . In the match_data structure, match_limit was an unsigned long int, whereas
2357     match_call_count was an int. I've made them both unsigned long ints.
2358    
2359     . In pcretest the fact that a const uschar * doesn't automatically cast to
2360     a void * provoked a warning.
2361    
2362     . Turning on some more compiler warnings threw up some "shadow" variables
2363     and a few more missing casts.
2364    
2365     4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
2366     option, a class that contained a single character with a value between 128
2367     and 255 (e.g. /[\xFF]/) caused PCRE to crash.
2368    
2369     5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
2370     option, a class that contained several characters, but with at least one
2371     whose value was between 128 and 255 caused PCRE to crash.
2372    
2373    
2374 nigel 65 Version 4.1 12-Mar-03
2375     ---------------------
2376 nigel 63
2377 nigel 65 1. Compiling with gcc -pedantic found a couple of places where casts were
2378     needed, and a string in dftables.c that was longer than standard compilers are
2379     required to support.
2380    
2381     2. Compiling with Sun's compiler found a few more places where the code could
2382     be tidied up in order to avoid warnings.
2383    
2384     3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
2385     first of these names is deprecated in the latest Autoconf in favour of the name
2386     CC_FOR_BUILD, because "host" is typically used to mean the system on which the
2387     compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
2388     analogy I have changed it to CFLAGS_FOR_BUILD.
2389    
2390     4. Added -no-undefined to the linking command in the Makefile, because this is
2391     apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
2392     linking step for the pcreposix library.
2393    
2394     5. PCRE was failing to diagnose the case of two named groups with the same
2395     name.
2396    
2397     6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
2398     literal character that is needed in the subject for a match, and scans along to
2399     ensure that it is present before embarking on the full matching process. This
2400     saves time in cases of nested unlimited repeats that are never going to match.
2401     Problem: the scan can take a lot of time if the subject is very long (e.g.
2402     megabytes), thus penalizing straightforward matches. It is now done only if the
2403     amount of subject to be scanned is less than 1000 bytes.
2404    
2405     7. A lesser problem with the same optimization is that it was recording the
2406     first character of an anchored pattern as "needed", thus provoking a search
2407     right along the subject, even when the first match of the pattern was going to
2408     fail. The "needed" character is now not set for anchored patterns, unless it
2409     follows something in the pattern that is of non-fixed length. Thus, it still
2410     fulfils its original purpose of finding quick non-matches in cases of nested
2411     unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.
2412    
2413    
2414     Version 4.0 17-Feb-03
2415     ---------------------
2416    
2417 nigel 63 1. If a comment in an extended regex that started immediately after a meta-item
2418     extended to the end of string, PCRE compiled incorrect data. This could lead to
2419     all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.
2420    
2421     2. Moved to autoconf 2.53 and libtool 1.4.2.
2422    
2423     3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
2424     the special perltest8 script is no longer needed - all the tests can be run
2425     from a single perltest script.
2426    
2427     4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
2428     by \s. It has now been removed in PCRE. This means it isn't recognized as
2429     whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
2430     class [:space:] *does* include VT, thereby creating a mess.
2431    
2432     5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
2433     space and tab.
2434    
2435     6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
2436     its new features into the main test script, reducing the number of scripts.
2437    
2438     7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
2439     were backward compatible, and made the (?i) apply to the whole pattern, as if
2440     /i were given. Now it behaves more logically, and applies the option setting
2441     only to what follows. PCRE has been changed to follow suit. However, if it
2442     finds options settings right at the start of the pattern, it extracts them into
2443     the global options, as before. Thus, they show up in the info data.
2444    
2445     8. Added support for the \Q...\E escape sequence. Characters in between are
2446     treated as literals. This is slightly different from Perl in that $ and @ are
2447     also handled as literals inside the quotes. In Perl, they will cause variable
2448     interpolation. Note the following examples:
2449    
2450     Pattern PCRE matches Perl matches
2451    
2452     \Qabc$xyz\E abc$xyz abc followed by the contents of $xyz
2453     \Qabc\$xyz\E abc\$xyz abc\$xyz
2454     \Qabc\E\$\Qxyz\E abc$xyz abc$xyz
2455    
2456     For compatibility with Perl, \Q...\E sequences are recognized inside character
2457     classes as well as outside them.
2458    
2459     9. Re-organized 3 code statements in pcretest to avoid "overflow in
2460     floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
2461     (size_t) cast to one statement in pcretest and one in pcreposix to avoid
2462     signed/unsigned warnings.
2463    
2464     10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
2465     option for pcretest, so I've replaced it by a simple function that does just
2466     that job.
2467    
2468     11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
2469     "pcregrep -".
2470    
2471     12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
2472     Java package. This provides some syntactic sugar for simple cases of what my
2473     documentation calls "once-only subpatterns". A pattern such as x*+ is the same
2474     as (?>x*). In other words, if what is inside (?>...) is just a single repeated
2475     item, you can use this simplified notation. Note that only makes sense with
2476     greedy quantifiers. Consequently, the use of the possessive quantifier forces
2477     greediness, whatever the setting of the PCRE_UNGREEDY option.
2478    
2479     13. A change of greediness default within a pattern was not taking effect at
2480     the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
2481     subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
2482     was abstracted outside.
2483    
2484     14. PCRE now supports the \G assertion. It is true when the current matching
2485     position is at the start point of the match. This differs from \A when the
2486     starting offset is non-zero. Used with the /g option of pcretest (or similar
2487     code), it works in the same way as it does for Perl's /g option. If all
2488     alternatives of a regex begin with \G, the expression is anchored to the start
2489     match position, and the "anchored" flag is set in the compiled expression.
2490    
2491     15. Some bugs concerning the handling of certain option changes within patterns
2492     have been fixed. These applied to options other than (?ims). For example,
2493     "a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
2494     been the other way round. Some of this was related to change 7 above.
2495    
2496     16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
2497     features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
2498     and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
2499     POSIX classes only within a class (e.g. /[[:alpha:]]/).
2500    
2501     17. Added support for Perl's \C escape. This matches one byte, even in UTF8
2502     mode. Unlike ".", it always matches newline, whatever the setting of
2503     PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
2504     assertions. Perl allows it, but it doesn't (in general) work because it can't
2505     calculate the length of the lookbehind. At least, that's the case for Perl
2506     5.8.0 - I've been told they are going to document that it doesn't work in
2507     future.
2508    
2509     18. Added an error diagnosis for escapes that PCRE does not support: these are
2510     \L, \l, \N, \P, \p, \U, \u, and \X.
2511    
2512     19. Although correctly diagnosing a missing ']' in a character class, PCRE was
2513     reading past the end of the pattern in cases such as /[abcd/.
2514    
2515     20. PCRE was getting more memory than necessary for patterns with classes that
2516     contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.
2517    
2518     21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
2519     compiling PCRE for use with Virtual Pascal.
2520    
2521     22. Small fix to the Makefile to make it work properly if the build is done
2522     outside the source tree.
2523    
2524     23. Added a new extension: a condition to go with recursion. If a conditional
2525     subpattern starts with (?(R) the "true" branch is used if recursion has
2526     happened, whereas the "false" branch is used only at the top level.
2527    
2528     24. When there was a very long string of literal characters (over 255 bytes
2529     without UTF support, over 250 bytes with UTF support), the computation of how
2530     much memory was required could be incorrect, leading to segfaults or other
2531     strange effects.
2532    
2533     25. PCRE was incorrectly assuming anchoring (either to start of subject or to
2534     start of line for a non-DOTALL pattern) when a pattern started with (.*) and
2535     there was a subsequent back reference to those brackets. This meant that, for
2536     example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
2537     possible to check for precisely this case. All we can do is abandon the
2538     optimization if .* occurs inside capturing brackets when there are any back
2539     references whatsoever. (See below for a better fix that came later.)
2540    
2541     26. The handling of the optimization for finding the first character of a
2542     non-anchored pattern, and for finding a character that is required later in the
2543     match were failing in some cases. This didn't break the matching; it just
2544     failed to optimize when it could. The way this is done has been re-implemented.
2545    
2546     27. Fixed typo in error message for invalid (?R item (it said "(?p").
2547    
2548     28. Added a new feature that provides some of the functionality that Perl
2549     provides with (?{...}). The facility is termed a "callout". The way it is done
2550     in PCRE is for the caller to provide an optional function, by setting
2551     pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
2552     global variable. By default it is unset, which disables all calling out. To get
2553     the function called, the regex must include (?C) at appropriate points. This
2554     is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
2555     This provides a means of identifying different callout points. When PCRE
2556     reaches such a point in the regex, if pcre_callout has been set, the external
2557     function is called. It is provided with data in a structure called
2558     pcre_callout_block, which is defined in pcre.h. If the function returns 0,
2559     matching continues; if it returns a non-zero value, the match at the current
2560     point fails. However, backtracking will occur if possible. [This was changed
2561     later and other features added - see item 49 below.]
2562    
2563     29. pcretest is upgraded to test the callout functionality. It provides a
2564     callout function that displays information. By default, it shows the start of
2565     the match and the current position in the text. There are some new data escapes
2566     to vary what happens:
2567    
2568     \C+ in addition, show current contents of captured substrings
2569     \C- do not supply a callout function
2570     \C!n return 1 when callout number n is reached
2571     \C!n!m return 1 when callout number n is reached for the mth time
2572    
2573     30. If pcregrep was called with the -l option and just a single file name, it
2574     output "<stdin>" if a match was found, instead of the file name.
2575    
2576     31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
2577     slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
2578     pcre_exec(). This saves a malloc/free per call. The default value of
2579     POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
2580     when configuring.
2581    
2582     32. The default maximum size of a compiled pattern is 64K. There have been a
2583     few cases of people hitting this limit. The code now uses macros to handle the
2584     storing of links as offsets within the compiled pattern. It defaults to 2-byte
2585     links, but this can be changed to 3 or 4 bytes by --with-link-size when
2586     configuring. Tests 2 and 5 work only with 2-byte links because they output
2587     debugging information about compiled patterns.
2588    
2589     33. Internal code re-arrangements:
2590    
2591     (a) Moved the debugging function for printing out a compiled regex into
2592     its own source file (printint.c) and used #include to pull it into
2593     pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
2594     separate copies.
2595    
2596     (b) Defined the list of op-code names for debugging as a macro in
2597     internal.h so that it is next to the definition of the opcodes.
2598    
2599     (c) Defined a table of op-code lengths for simpler skipping along compiled
2600     code. This is again a macro in internal.h so that it is next to the
2601     definition of the opcodes.
2602    
2603     34. Added support for recursive calls to individual subpatterns, along the
2604     lines of Robin Houston's patch (but implemented somewhat differently).
2605    
2606     35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
2607     allow it to read and process whole directories in Win32. This code was
2608     contributed by Lionel Fourquaux; it has not been tested by me.
2609    
2610     36. Added support for named subpatterns. The Python syntax (?P<name>...) is
2611     used to name a group. Names consist of alphanumerics and underscores, and must
2612     be unique. Back references use the syntax (?P=name) and recursive calls use
2613     (?P>name) which is a PCRE extension to the Python extension. Groups still have
2614     numbers. The function pcre_fullinfo() can be used after compilation to extract
2615     a name/number map. There are three relevant calls:
2616    
2617     PCRE_INFO_NAMEENTRYSIZE yields the size of each entry in the map
2618     PCRE_INFO_NAMECOUNT yields the number of entries
2619     PCRE_INFO_NAMETABLE yields a pointer to the map.
2620    
2621     The map is a vector of fixed-size entries. The size of each entry depends on
2622     the length of the longest name used. The first two bytes of each entry are the
2623     group number, most significant byte first. There follows the corresponding
2624     name, zero terminated. The names are in alphabetical order.
2625    
2626     37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
2627     case instead of 255. Making it the same both with and without UTF-8 support
2628     means that the same test output works with both.
2629    
2630     38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
2631     calling malloc() with a zero argument.
2632    
2633     39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
2634     optimization. I've improved things by keeping a bitmap of backreferences with
2635     numbers 1-31 so that if .* occurs inside capturing brackets that are not in
2636     fact referenced, the optimization can be applied. It is unlikely that a
2637     relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
2638     the match to follow \n) will appear inside brackets with a number greater than
2639     31, but if it does, any back reference > 31 suppresses the optimization.
2640    
2641     40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
2642     of disabling numbered capturing parentheses. Any opening parenthesis that is
2643     not followed by ? behaves as if it were followed by ?: but named parentheses
2644     can still be used for capturing (and they will acquire numbers in the usual
2645     way).
2646    
2647     41. Redesigned the return codes from the match() function into yes/no/error so
2648     that errors can be passed back from deep inside the nested calls. A malloc
2649     failure while inside a recursive subpattern call now causes the
2650     PCRE_ERROR_NOMEMORY return instead of quietly going wrong.
2651    
2652     42. It is now possible to set a limit on the number of times the match()
2653     function is called in a call to pcre_exec(). This facility makes it possible to
2654     limit the amount of recursion and backtracking, though not in a directly
2655     obvious way, because the match() function is used in a number of different
2656     circumstances. The count starts from zero for each position in the subject
2657     string (for non-anchored patterns). The default limit is, for compatibility, a
2658     large number, namely 10 000 000. You can change this in two ways:
2659    
2660     (a) When configuring PCRE before making, you can use --with-match-limit=n
2661     to set a default value for the compiled library.
2662    
2663     (b) For each call to pcre_exec(), you can pass a pcre_extra block in which
2664     a different value is set. See 45 below.
2665    
2666     If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
2667    
2668     43. Added a new function pcre_config(int, void *) to enable run-time extraction
2669     of things that can be changed at compile time. The first argument specifies
2670     what is wanted and the second points to where the information is to be placed.
2671     The current list of available information is:
2672    
2673     PCRE_CONFIG_UTF8
2674    
2675     The output is an integer that is set to one if UTF-8 support is available;
2676     otherwise it is set to zero.
2677    
2678     PCRE_CONFIG_NEWLINE
2679    
2680     The output is an integer that it set to the value of the code that is used for
2681     newline. It is either LF (10) or CR (13).
2682    
2683     PCRE_CONFIG_LINK_SIZE
2684    
2685     The output is an integer that contains the number of bytes used for internal
2686     linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.
2687    
2688     PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
2689    
2690     The output is an integer that contains the threshold above which the POSIX
2691     interface uses malloc() for output vectors. See item 31 above.
2692    
2693     PCRE_CONFIG_MATCH_LIMIT
2694    
2695     The output is an unsigned integer that contains the default limit of the number
2696     of match() calls in a pcre_exec() execution. See 42 above.
2697    
2698     44. pcretest has been upgraded by the addition of the -C option. This causes it
2699     to extract all the available output from the new pcre_config() function, and to
2700     output it. The program then exits immediately.
2701    
2702     45. A need has arisen to pass over additional data with calls to pcre_exec() in
2703     order to support additional features. One way would have been to define
2704     pcre_exec2() (for example) with extra arguments, but this would not have been
2705     extensible, and would also have required all calls to the original function to
2706     be mapped to the new one. Instead, I have chosen to extend the mechanism that
2707     is used for passing in "extra" data from pcre_study().
2708    
2709     The pcre_extra structure is now exposed and defined in pcre.h. It currently
2710     contains the following fields:
2711    
2712     flags a bitmap indicating which of the following fields are set
2713     study_data opaque data from pcre_study()
2714     match_limit a way of specifying a limit on match() calls for a specific
2715     call to pcre_exec()
2716     callout_data data for callouts (see 49 below)
2717    
2718     The flag bits are also defined in pcre.h, and are
2719    
2720     PCRE_EXTRA_STUDY_DATA
2721     PCRE_EXTRA_MATCH_LIMIT
2722     PCRE_EXTRA_CALLOUT_DATA
2723    
2724     The pcre_study() function now returns one of these new pcre_extra blocks, with
2725     the actual study data pointed to by the study_data field, and the
2726     PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
2727     before. That is, this change is entirely upwards-compatible and requires no
2728     change to existing code.
2729    
2730     If you want to pass in additional data to pcre_exec(), you can either place it
2731     in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
2732     block.
2733    
2734     46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
2735     data string contains the escape sequence \M, pcretest calls pcre_exec() several
2736     times with different match limits, until it finds the minimum value needed for
2737     pcre_exec() to complete. The value is then output. This can be instructive; for
2738     most simple matches the number is quite small, but for pathological cases it
2739     gets very large very quickly.
2740    
2741     47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
2742     returns the size of the data block pointed to by the study_data field in a
2743     pcre_extra block, that is, the value that was passed as the argument to
2744     pcre_malloc() when PCRE was getting memory in which to place the information
2745     created by pcre_study(). The fourth argument should point to a size_t variable.
2746     pcretest has been extended so that this information is shown after a successful
2747     pcre_study() call when information about the compiled regex is being displayed.
2748    
2749     48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
2750     because what follows is always an absolute path. (Later: it turns out that this
2751     is more than cosmetic for MinGW, because it doesn't like empty path
2752     components.)
2753    
2754     49. Some changes have been made to the callout feature (see 28 above):
2755    
2756     (i) A callout function now has three choices for what it returns:
2757    
2758     0 => success, carry on matching
2759     > 0 => failure at this point, but backtrack if possible
2760     < 0 => serious error, return this value from pcre_exec()
2761    
2762     Negative values should normally be chosen from the set of PCRE_ERROR_xxx
2763     values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
2764     "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
2765     use by callout functions. It will never be used by PCRE itself.
2766    
2767     (ii) The pcre_extra structure (see 45 above) has a void * field called
2768     callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
2769     pcre_callout_block structure has a field of the same name. The contents of
2770     the field passed in the pcre_extra structure are passed to the callout
2771     function in the corresponding field in the callout block. This makes it
2772     easier to use the same callout-containing regex from multiple threads. For
2773     testing, the pcretest program has a new data escape
2774    
2775     \C*n pass the number n (may be negative) as callout_data
2776    
2777     If the callout function in pcretest receives a non-zero value as
2778     callout_data, it returns that value.
2779    
2780     50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
2781     there were some redundant $(CFLAGS) in commands that are now specified as
2782     $(LINK), which already includes $(CFLAGS).
2783    
2784     51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
2785     has been compiled with UTF-8 support *and* pcre_compile() has been compiled
2786     with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
2787     one-byte characters throughout. Note that case-insensitive matching applies
2788     only to characters whose values are less than 256. PCRE doesn't support the
2789     notion of cases for higher-valued characters.
2790    
2791     (i) A character class whose characters are all within 0-255 is handled as
2792     a bit map, and the map is inverted for negative classes. Previously, a
2793     character > 255 always failed to match such a class; however it should
2794     match if the class was a negative one (e.g. [^ab]). This has been fixed.
2795    
2796     (ii) A negated character class with a single character < 255 is coded as
2797     "not this character" (OP_NOT). This wasn't working properly when the test
2798     character was multibyte, either singly or repeated.
2799    
2800     (iii) Repeats of multibyte characters are now handled correctly in UTF-8
2801     mode, for example: \x{100}{2,3}.
2802    
2803     (iv) The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
2804     singly or repeated) now correctly test multibyte characters. However,
2805     PCRE doesn't recognize any characters with values greater than 255 as
2806     digits, spaces, or word characters. Such characters always match \D, \S,
2807     and \W, and never match \d, \s, or \w.
2808    
2809     (v) Classes may now contain characters and character ranges with values
2810     greater than 255. For example: [ab\x{100}-\x{400}].
2811    
2812     (vi) pcregrep now has a --utf-8 option (synonym -u) which makes it call
2813     PCRE in UTF-8 mode.
2814    
2815     52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
2816     PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
2817     retained for backwards compatibility. (Note that LASTLITERAL is also a byte
2818     value.)
2819    
2820     53. The single man page has become too large. I have therefore split it up into
2821     a number of separate man pages. These also give rise to individual HTML pages;
2822     these are now put in a separate directory, and there is an index.html page that
2823     lists them all. Some hyperlinking between the pages has been installed.
2824    
2825     54. Added convenience functions for handling named capturing parentheses.
2826    
2827     55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
2828     aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
2829     true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
2830     are faulted.
2831    
2832     56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
2833     calling configure. These values are used when compiling the dftables.c program
2834     which is run to generate the source of the default character tables. They
2835     default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
2836     you will need to set these values.
2837    
2838     57. Updated the building process for Windows DLL, as provided by Fred Cox.
2839    
2840    
2841     Version 3.9 02-Jan-02
2842 nigel 61 ---------------------
2843    
2844     1. A bit of extraneous text had somehow crept into the pcregrep documentation.
2845    
2846     2. If --disable-static was given, the building process failed when trying to
2847     build pcretest and pcregrep. (For some reason it was using libtool to compile
2848     them, which is not right, as they aren't part of the library.)
2849    
2850    
2851 nigel 59 Version 3.8 18-Dec-01
2852     ---------------------
2853    
2854     1. The experimental UTF-8 code was completely screwed up. It was packing the
2855     bytes in the wrong order. How dumb can you get?
2856    
2857    
2858 nigel 57 Version 3.7 29-Oct-01
2859     ---------------------
2860    
2861     1. In updating pcretest to check change 1 of version 3.6, I screwed up.
2862     This caused pcretest, when used on the test data, to segfault. Unfortunately,
2863     this didn't happen under Solaris 8, where I normally test things.
2864    
2865 nigel 59 2. The Makefile had to be changed to make it work on BSD systems, where 'make'
2866     doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
2867     isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
2868     this fix an hour or so after the initial 3.7 release.)
2869 nigel 57
2870 nigel 59
2871 nigel 55 Version 3.6 23-Oct-01
2872     ---------------------
2873    
2874     1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
2875     offsets passed as NULL with zero offset count.
2876    
2877     2. The config.guess and config.sub files had not been updated when I moved to
2878     the latest autoconf.
2879    
2880    
2881 nigel 53 Version 3.5 15-Aug-01
2882     ---------------------
2883 nigel 5
2884 nigel 53 1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
2885     had been forgotten.
2886    
2887     2. By using declared but undefined structures, we can avoid using "void"
2888     definitions in pcre.h while keeping the internal definitions of the structures
2889     private.
2890    
2891     3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
2892     user point of view, this means that both static and shared libraries are built
2893     by default, but this can be individually controlled. More of the work of
2894     handling this static/shared cases is now inside libtool instead of PCRE's make
2895     file.
2896    
2897     4. The pcretest utility is now installed along with pcregrep because it is
2898     useful for users (to test regexs) and by doing this, it automatically gets
2899     relinked by libtool. The documentation has been turned into a man page, so
2900     there are now .1, .txt, and .html versions in /doc.
2901    
2902     5. Upgrades to pcregrep:
2903     (i) Added long-form option names like gnu grep.
2904     (ii) Added --help to list all options with an explanatory phrase.
2905     (iii) Added -r, --recursive to recurse into sub-directories.
2906     (iv) Added -f, --file to read patterns from a file.
2907    
2908     6. pcre_exec() was referring to its "code" argument before testing that
2909     argument for NULL (and giving an error if it was NULL).
2910    
2911     7. Upgraded Makefile.in to allow for compiling in a different directory from
2912     the source directory.
2913    
2914     8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
2915     options bits, the pointer it was passed was to an int instead of to an unsigned
2916     long int. This mattered only on 64-bit systems.
2917    
2918     9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
2919     generated) instead of pcre.in, which it its source. Also made the same change
2920     in several of the .c files.
2921    
2922     10. A new release of gcc defines printf() as a macro, which broke pcretest
2923     because it had an ifdef in the middle of a string argument for printf(). Fixed
2924     by using separate calls to printf().
2925    
2926     11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
2927     script, to force use of CR or LF instead of \n in the source. On non-Unix
2928     systems, the value can be set in config.h.
2929    
2930     12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
2931     absolute limit. Changed the text of the error message to make this clear, and
2932     likewise updated the man page.
2933    
2934     13. The limit of 99 on the number of capturing subpatterns has been removed.
2935     The new limit is 65535, which I hope will not be a "real" limit.
2936    
2937    
2938 nigel 51 Version 3.4 22-Aug-00
2939     ---------------------
2940    
2941     1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.
2942    
2943     2. Diagnose condition (?(0) as an error instead of crashing on matching.
2944    
2945    
2946 nigel 49 Version 3.3 01-Aug-00
2947     ---------------------
2948    
2949     1. If an octal character was given, but the value was greater than \377, it
2950     was not getting masked to the least significant bits, as documented. This could
2951     lead to crashes in some systems.
2952    
2953     2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
2954     the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.
2955    
2956     3. Added the functions pcre_free_substring() and pcre_free_substring_list().
2957     These just pass their arguments on to (pcre_free)(), but they are provided
2958     because some uses of PCRE bind it to non-C systems that can call its functions,
2959     but cannot call free() or pcre_free() directly.
2960    
2961     4. Add "make test" as a synonym for "make check". Corrected some comments in
2962     the Makefile.
2963    
2964     5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
2965     Makefile.
2966    
2967     6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
2968     command called pgrep for grepping around the active processes.
2969    
2970     7. Added the beginnings of support for UTF-8 character strings.
2971    
2972     8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
2973     RANLIB to ./ltconfig so that they are used by libtool. I think these are all
2974     the relevant ones. (AR is not passed because ./ltconfig does its own figuring
2975     out for the ar command.)
2976    
2977    
2978 nigel 47 Version 3.2 12-May-00
2979     ---------------------
2980    
2981     This is purely a bug fixing release.
2982    
2983     1. If the pattern /((Z)+|A)*/ was matched agained ZABCDEFG it matched Z instead
2984     of ZA. This was just one example of several cases that could provoke this bug,
2985     which was introduced by change 9 of version 2.00. The code for breaking
2986     infinite loops after an iteration that matches an empty string was't working
2987     correctly.
2988    
2989     2. The pcretest program was not imitating Perl correctly for the pattern /a*/g
2990     when matched against abbab (for example). After matching an empty string, it
2991     wasn't forcing anchoring when setting PCRE_NOTEMPTY for the next attempt; this
2992     caused it to match further down the string than it should.
2993    
2994     3. The code contained an inclusion of sys/types.h. It isn't clear why this
2995     was there because it doesn't seem to be needed, and it causes trouble on some
2996     systems, as it is not a Standard C header. It has been removed.
2997    
2998     4. Made 4 silly changes to the source to avoid stupid compiler warnings that
2999     were reported on the Macintosh. The changes were from
3000    
3001     while ((c = *(++ptr)) != 0 && c != '\n');
3002     to
3003     while ((c = *(++ptr)) != 0 && c != '\n') ;
3004    
3005     Totally extraordinary, but if that's what it takes...
3006    
3007     5. PCRE is being used in one environment where neither memmove() nor bcopy() is
3008     available. Added HAVE_BCOPY and an autoconf test for it; if neither
3009     HAVE_MEMMOVE nor HAVE_BCOPY is set, use a built-in emulation function which
3010     assumes the way PCRE uses memmove() (always moving upwards).
3011    
3012     6. PCRE is being used in one environment where strchr() is not available. There
3013     was only one use in pcre.c, and writing it out to avoid strchr() probably gives
3014     faster code anyway.
3015    
3016    
3017 nigel 45 Version 3.1 09-Feb-00
3018     ---------------------
3019    
3020     The only change in this release is the fixing of some bugs in Makefile.in for
3021     the "install" target:
3022    
3023     (1) It was failing to install pcreposix.h.
3024    
3025     (2) It was overwriting the pcre.3 man page with the pcreposix.3 man page.
3026    
3027    
3028 nigel 43 Version 3.0 01-Feb-00
3029     ---------------------
3030 nigel 41
3031     1. Add support for the /+ modifier to perltest (to output $` like it does in
3032     pcretest).
3033    
3034     2. Add support for the /g modifier to perltest.
3035    
3036     3. Fix pcretest so that it behaves even more like Perl for /g when the pattern
3037     matches null strings.
3038    
3039     4. Fix perltest so that it doesn't do unwanted things when fed an empty
3040     pattern. Perl treats empty patterns specially - it reuses the most recent
3041     pattern, which is not what we want. Replace // by /(?#)/ in order to avoid this
3042     effect.
3043    
3044     5. The POSIX interface was broken in that it was just handing over the POSIX
3045     captured string vector to pcre_exec(), but (since release 2.00) PCRE has
3046     required a bigger vector, with some working space on the end. This means that
3047     the POSIX wrapper now has to get and free some memory, and copy the results.
3048    
3049 nigel 43 6. Added some simple autoconf support, placing the test data and the
3050     documentation in separate directories, re-organizing some of the
3051     information files, and making it build pcre-config (a GNU standard). Also added
3052     libtool support for building PCRE as a shared library, which is now the
3053     default.
3054 nigel 41
3055 nigel 43 7. Got rid of the leading zero in the definition of PCRE_MINOR because 08 and
3056     09 are not valid octal constants. Single digits will be used for minor values
3057     less than 10.
3058    
3059     8. Defined REG_EXTENDED and REG_NOSUB as zero in the POSIX header, so that
3060     existing programs that set these in the POSIX interface can use PCRE without
3061     modification.
3062    
3063     9. Added a new function, pcre_fullinfo() with an extensible interface. It can
3064     return all that pcre_info() returns, plus additional data. The pcre_info()
3065     function is retained for compatibility, but is considered to be obsolete.
3066    
3067     10. Added experimental recursion feature (?R) to handle one common case that
3068     Perl 5.6 will be able to do with (?p{...}).
3069    
3070     11. Added support for POSIX character classes like [:alpha:], which Perl is
3071     adopting.
3072    
3073    
3074 nigel 39 Version 2.08 31-Aug-99
3075     ----------------------
3076    
3077     1. When startoffset was not zero and the pattern began with ".*", PCRE was not
3078     trying to match at the startoffset position, but instead was moving forward to
3079     the next newline as if a previous match had failed.
3080    
3081     2. pcretest was not making use of PCRE_NOTEMPTY when repeating for /g and /G,
3082     and could get into a loop if a null string was matched other than at the start
3083     of the subject.
3084    
3085     3. Added definitions of PCRE_MAJOR and PCRE_MINOR to pcre.h so the version can
3086     be distinguished at compile time, and for completeness also added PCRE_DATE.
3087    
3088     5. Added Paul Sokolovsky's minor changes to make it easy to compile a Win32 DLL
3089     in GnuWin32 environments.
3090    
3091    
3092 nigel 37 Version 2.07 29-Jul-99
3093     ----------------------
3094    
3095     1. The documentation is now supplied in plain text form and HTML as well as in
3096     the form of man page sources.
3097    
3098     2. C++ compilers don't like assigning (void *) values to other pointer types.
3099     In particular this affects malloc(). Although there is no problem in Standard
3100     C, I've put in casts to keep C++ compilers happy.
3101    
3102     3. Typo on pcretest.c; a cast of (unsigned char *) in the POSIX regexec() call
3103     should be (const char *).
3104    
3105     4. If NOPOSIX is defined, pcretest.c compiles without POSIX support. This may
3106     be useful for non-Unix systems who don't want to bother with the POSIX stuff.
3107     However, I haven't made this a standard facility. The documentation doesn't
3108     mention it, and the Makefile doesn't support it.
3109    
3110     5. The Makefile now contains an "install" target, with editable destinations at
3111     the top of the file. The pcretest program is not installed.
3112    
3113     6. pgrep -V now gives the PCRE version number and date.
3114    
3115     7. Fixed bug: a zero repetition after a literal string (e.g. /abcde{0}/) was
3116     causing the entire string to be ignored, instead of just the last character.
3117    
3118     8. If a pattern like /"([^\\"]+|\\.)*"/ is applied in the normal way to a
3119     non-matching string, it can take a very, very long time, even for strings of
3120     quite modest length, because of the nested recursion. PCRE now does better in
3121     some of these cases. It does this by remembering the last required literal
3122     character in the pattern, and pre-searching the subject to ensure it is present
3123     before running the real match. In other words, it applies a heuristic to detect
3124     some types of certain failure quickly, and in the above example, if presented
3125     with a string that has no trailing " it gives "no match" very quickly.
3126    
3127     9. A new runtime option PCRE_NOTEMPTY causes null string matches to be ignored;
3128     other alternatives are tried instead.
3129    
3130    
3131 nigel 35 Version 2.06 09-Jun-99
3132     ----------------------
3133    
3134     1. Change pcretest's output for amount of store used to show just the code
3135     space, because the remainder (the data block) varies in size between 32-bit and
3136     64-bit systems.
3137    
3138     2. Added an extra argument to pcre_exec() to supply an offset in the subject to
3139     start matching at. This allows lookbehinds to work when searching for multiple
3140     occurrences in a string.
3141    
3142     3. Added additional options to pcretest for testing multiple occurrences:
3143    
3144     /+ outputs the rest of the string that follows a match
3145     /g loops for multiple occurrences, using the new startoffset argument
3146     /G loops for multiple occurrences by passing an incremented pointer
3147    
3148     4. PCRE wasn't doing the "first character" optimization for patterns starting
3149     with \b or \B, though it was doing it for other lookbehind assertions. That is,
3150     it wasn't noticing that a match for a pattern such as /\bxyz/ has to start with
3151     the letter 'x'. On long subject strings, this gives a significant speed-up.
3152    
3153    
3154 nigel 33 Version 2.05 21-Apr-99
3155     ----------------------
3156    
3157     1. Changed the type of magic_number from int to long int so that it works
3158     properly on 16-bit systems.
3159    
3160     2. Fixed a bug which caused patterns starting with .* not to work correctly
3161     when the subject string contained newline characters. PCRE was assuming
3162     anchoring for such patterns in all cases, which is not correct because .* will
3163     not pass a newline unless PCRE_DOTALL is set. It now assumes anchoring only if
3164     DOTALL is set at top level; otherwise it knows that patterns starting with .*
3165     must be retried after every newline in the subject.
3166    
3167    
3168 nigel 31 Version 2.04 18-Feb-99
3169     ----------------------
3170    
3171     1. For parenthesized subpatterns with repeats whose minimum was zero, the
3172     computation of the store needed to hold the pattern was incorrect (too large).
3173     If such patterns were nested a few deep, this could multiply and become a real
3174     problem.
3175    
3176     2. Added /M option to pcretest to show the memory requirement of a specific
3177     pattern. Made -m a synonym of -s (which does this globally) for compatibility.
3178    
3179     3. Subpatterns of the form (regex){n,m} (i.e. limited maximum) were being
3180     compiled in such a way that the backtracking after subsequent failure was
3181     pessimal. Something like (a){0,3} was compiled as (a)?(a)?(a)? instead of
3182     ((a)((a)(a)?)?)? with disastrous performance if the maximum was of any size.
3183    
3184    
3185 nigel 29 Version 2.03 02-Feb-99
3186     ----------------------
3187    
3188     1. Fixed typo and small mistake in man page.
3189    
3190 nigel 31 2. Added 4th condition (GPL supersedes if conflict) and created separate
3191     LICENCE file containing the conditions.
3192 nigel 29
3193     3. Updated pcretest so that patterns such as /abc\/def/ work like they do in
3194     Perl, that is the internal \ allows the delimiter to be included in the
3195     pattern. Locked out the use of \ as a delimiter. If \ immediately follows
3196     the final delimiter, add \ to the end of the pattern (to test the error).
3197    
3198     4. Added the convenience functions for extracting substrings after a successful
3199     match. Updated pcretest to make it able to test these functions.
3200    
3201    
3202 nigel 27 Version 2.02 14-Jan-99
3203     ----------------------
3204    
3205     1. Initialized the working variables associated with each extraction so that
3206     their saving and restoring doesn't refer to uninitialized store.
3207    
3208     2. Put dummy code into study.c in order to trick the optimizer of the IBM C
3209     compiler for OS/2 into generating correct code. Apparently IBM isn't going to
3210     fix the problem.
3211    
3212     3. Pcretest: the timing code wasn't using LOOPREPEAT for timing execution
3213     calls, and wasn't printing the correct value for compiling calls. Increased the
3214     default value of LOOPREPEAT, and the number of significant figures in the
3215     times.
3216    
3217     4. Changed "/bin/rm" in the Makefile to "-rm" so it works on Windows NT.
3218    
3219     5. Renamed "deftables" as "dftables" to get it down to 8 characters, to avoid
3220     a building problem on Windows NT with a FAT file system.
3221    
3222    
3223 nigel 25 Version 2.01 21-Oct-98
3224     ----------------------
3225    
3226     1. Changed the API for pcre_compile() to allow for the provision of a pointer
3227     to character tables built by pcre_maketables() in the current locale. If NULL
3228     is passed, the default tables are used.
3229    
3230    
3231 nigel 23 Version 2.00 24-Sep-98
3232 nigel 21 ----------------------
3233    
3234 nigel 23 1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
3235     it any more.
3236    
3237     2. Allow quantification of (?>) groups, and make it work correctly.
3238    
3239     3. The first character computation wasn't working for (?>) groups.
3240    
3241     4. Correct the implementation of \Z (it is permitted to match on the \n at the
3242     end of the subject) and add 5.005's \z, which really does match only at the
3243     very end of the subject.
3244    
3245     5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.
3246    
3247     6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
3248     DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
3249     localized options. All options to pcre_study() were also removed.
3250    
3251     7. Add other new features from 5.005:
3252    
3253     $(?<= positive lookbehind
3254     $(?<! negative lookbehind
3255     (?imsx-imsx) added the unsetting capability
3256     such a setting is global if at outer level; local otherwise
3257     (?imsx-imsx:) non-capturing groups with option setting
3258     (?(cond)re|re) conditional pattern matching
3259    
3260     A backreference to itself in a repeated group matches the previous
3261     captured string.
3262    
3263     8. General tidying up of studying (both automatic and via "study")
3264     consequential on the addition of new assertions.
3265    
3266     9. As in 5.005, unlimited repeated groups that could match an empty substring
3267     are no longer faulted at compile time. Instead, the loop is forcibly broken at
3268     runtime if any iteration does actually match an empty substring.
3269    
3270     10. Include the RunTest script in the distribution.
3271    
3272     11. Added tests from the Perl 5.005_02 distribution. This showed up a few
3273     discrepancies, some of which were old and were also with respect to 5.004. They
3274     have now been fixed.
3275    
3276    
3277     Version 1.09 28-Apr-98
3278     ----------------------
3279    
3280 nigel 21 1. A negated single character class followed by a quantifier with a minimum
3281     value of one (e.g. [^x]{1,6} ) was not compiled correctly. This could lead to
3282     program crashes, or just wrong answers. This did not apply to negated classes
3283     containing more than one character, or to minima other than one.
3284    
3285    
3286 nigel 19 Version 1.08 27-Mar-98
3287     ----------------------
3288    
3289     1. Add PCRE_UNGREEDY to invert the greediness of quantifiers.
3290    
3291     2. Add (?U) and (?X) to set PCRE_UNGREEDY and PCRE_EXTRA respectively. The
3292     latter must appear before anything that relies on it in the pattern.
3293    
3294    
3295 nigel 17 Version 1.07 16-Feb-98
3296     ----------------------
3297    
3298     1. A pattern such as /((a)*)*/ was not being diagnosed as in error (unlimited
3299     repeat of a potentially empty string).
3300    
3301    
3302 nigel 15 Version 1.06 23-Jan-98
3303     ----------------------
3304    
3305     1. Added Markus Oberhumer's little patches for C++.
3306    
3307     2. Literal strings longer than 255 characters were broken.
3308    
3309    
3310 nigel 13 Version 1.05 23-Dec-97
3311     ----------------------
3312    
3313     1. Negated character classes containing more than one character were failing if
3314     PCRE_CASELESS was set at run time.
3315    
3316    
3317 nigel 11 Version 1.04 19-Dec-97
3318     ----------------------
3319    
3320     1. Corrected the man page, where some "const" qualifiers had been omitted.
3321    
3322     2. Made debugging output print "{0,xxx}" instead of just "{,xxx}" to agree with
3323     input syntax.
3324    
3325     3. Fixed memory leak which occurred when a regex with back references was
3326     matched with an offsets vector that wasn't big enough. The temporary memory
3327     that is used in this case wasn't being freed if the match failed.
3328    
3329     4. Tidied pcretest to ensure it frees memory that it gets.
3330    
3331     5. Temporary memory was being obtained in the case where the passed offsets
3332     vector was exactly big enough.
3333    
3334     6. Corrected definition of offsetof() from change 5 below.
3335    
3336     7. I had screwed up change 6 below and broken the rules for the use of
3337     setjmp(). Now fixed.
3338    
3339    
3340 nigel 9 Version 1.03 18-Dec-97
3341     ----------------------
3342    
3343     1. A erroneous regex with a missing opening parenthesis was correctly
3344     diagnosed, but PCRE attempted to access brastack[-1], which could cause crashes
3345     on some systems.
3346    
3347     2. Replaced offsetof(real_pcre, code) by offsetof(real_pcre, code[0]) because
3348     it was reported that one broken compiler failed on the former because "code" is
3349     also an independent variable.
3350    
3351     3. The erroneous regex a[]b caused an array overrun reference.
3352    
3353     4. A regex ending with a one-character negative class (e.g. /[^k]$/) did not
3354     fail on data ending with that character. (It was going on too far, and checking
3355     the next character, typically a binary zero.) This was specific to the
3356     optimized code for single-character negative classes.
3357    
3358     5. Added a contributed patch from the TIN world which does the following:
3359    
3360     + Add an undef for memmove, in case the the system defines a macro for it.
3361    
3362     + Add a definition of offsetof(), in case there isn't one. (I don't know
3363     the reason behind this - offsetof() is part of the ANSI standard - but
3364     it does no harm).
3365    
3366     + Reduce the ifdef's in pcre.c using macro DPRINTF, thereby eliminating
3367     most of the places where whitespace preceded '#'. I have given up and
3368     allowed the remaining 2 cases to be at the margin.
3369    
3370     + Rename some variables in pcre to eliminate shadowing. This seems very
3371     pedantic, but does no harm, of course.
3372    
3373     6. Moved the call to setjmp() into its own function, to get rid of warnings
3374     from gcc -Wall, and avoided calling it at all unless PCRE_EXTRA is used.
3375    
3376     7. Constructs such as \d{8,} were compiling into the equivalent of
3377 nigel 11 \d{8}\d{0,65527} instead of \d{8}\d* which didn't make much difference to the
3378 nigel 9 outcome, but in this particular case used more store than had been allocated,
3379     which caused the bug to be discovered because it threw up an internal error.
3380    
3381     8. The debugging code in both pcre and pcretest for outputting the compiled
3382     form of a regex was going wrong in the case of back references followed by
3383     curly-bracketed repeats.
3384    
3385    
3386 nigel 7 Version 1.02 12-Dec-97
3387     ----------------------
3388    
3389     1. Typos in pcre.3 and comments in the source fixed.
3390    
3391     2. Applied a contributed patch to get rid of places where it used to remove
3392     'const' from variables, and fixed some signed/unsigned and uninitialized
3393     variable warnings.
3394    
3395     3. Added the "runtest" target to Makefile.
3396    
3397     4. Set default compiler flag to -O2 rather than just -O.
3398    
3399    
3400 nigel 5 Version 1.01 19-Nov-97
3401     ----------------------
3402    
3403     1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
3404     like /([ab]*)*/, that is, for classes with more than one character in them.
3405    
3406     2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
3407     as /((?>a*))*/ (a PCRE_EXTRA facility).
3408    
3409    
3410     Version 1.00 18-Nov-97
3411     ----------------------
3412    
3413     1. Added compile-time macros to support systems such as SunOS4 which don't have
3414     memmove() or strerror() but have other things that can be used instead.
3415    
3416     2. Arranged that "make clean" removes the executables.
3417    
3418    
3419 nigel 3 Version 0.99 27-Oct-97
3420     ----------------------
3421    
3422     1. Fixed bug in code for optimizing classes with only one character. It was
3423     initializing a 32-byte map regardless, which could cause it to run off the end
3424     of the memory it had got.
3425    
3426     2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
3427    
3428    
3429     Version 0.98 22-Oct-97
3430     ----------------------
3431    
3432     1. Fixed bug in code for handling temporary memory usage when there are more
3433     back references than supplied space in the ovector. This could cause segfaults.
3434    
3435    
3436     Version 0.97 21-Oct-97
3437     ----------------------
3438    
3439     1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
3440    
3441     2. Optimized negated single characters not to use a bit map.
3442    
3443     3. Brought error texts together as macro definitions; clarified some of them;
3444     fixed one that was wrong - it said "range out of order" when it meant "invalid
3445     escape sequence".
3446    
3447     4. Changed some char * arguments to const char *.
3448    
3449     5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
3450    
3451     6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
3452     pcretest.
3453    
3454    
3455     Version 0.96 16-Oct-97
3456     ----------------------
3457    
3458     1. Added a simple "pgrep" utility to the distribution.
3459    
3460     2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
3461     unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
3462     where "ddd" means "one or more decimal digits".
3463    
3464     3. Fixed serious bug. If a pattern had a back reference, but the call to
3465     pcre_exec() didn't supply a large enough ovector to record the related
3466     identifying subpattern, the match always failed. PCRE now remembers the number
3467     of the largest back reference, and gets some temporary memory in which to save
3468     the offsets during matching if necessary, in order to ensure that
3469     backreferences always work.
3470    
3471     4. Increased the compatibility with Perl in a number of ways:
3472    
3473     (a) . no longer matches \n by default; an option PCRE_DOTALL is provided
3474     to request this handling. The option can be set at compile or exec time.
3475    
3476     (b) $ matches before a terminating newline by default; an option
3477     PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
3478     mode). The option can be set at compile or exec time.
3479    
3480     (c) The handling of \ followed by a digit other than 0 is now supposed to be
3481     the same as Perl's. If the decimal number it represents is less than 10
3482     or there aren't that many previous left capturing parentheses, an octal
3483     escape is read. Inside a character class, it's always an octal escape,
3484     even if it is a single digit.
3485    
3486     (d) An escaped but undefined alphabetic character is taken as a literal,
3487     unless PCRE_EXTRA is set. Currently this just reserves the remaining
3488     escapes.
3489    
3490     (e) {0} is now permitted. (The previous item is removed from the compiled
3491     pattern).
3492    
3493     5. Changed all the names of code files so that the basic parts are no longer
3494     than 10 characters, and abolished the teeny "globals.c" file.
3495    
3496     6. Changed the handling of character classes; they are now done with a 32-byte
3497     bit map always.
3498    
3499     7. Added the -d and /D options to pcretest to make it possible to look at the
3500     internals of compilation without having to recompile pcre.
3501    
3502    
3503     Version 0.95 23-Sep-97
3504     ----------------------
3505    
3506     1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
3507     \x20 at the start of a run of normal characters. These were being treated as
3508     real characters, instead of the source characters being re-checked.
3509    
3510    
3511     Version 0.94 18-Sep-97
3512     ----------------------
3513    
3514     1. The functions are now thread-safe, with the caveat that the global variables
3515     containing pointers to malloc() and free() or alternative functions are the
3516     same for all threads.
3517    
3518     2. Get pcre_study() to generate a bitmap of initial characters for non-
3519     anchored patterns when this is possible, and use it if passed to pcre_exec().
3520    
3521    
3522     Version 0.93 15-Sep-97
3523     ----------------------
3524    
3525     1. /(b)|(:+)/ was computing an incorrect first character.
3526    
3527     2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
3528     but not actually doing anything yet.
3529    
3530     3. Treat "-" characters in classes that cannot be part of ranges as literals,
3531     as Perl does (e.g. [-az] or [az-]).
3532    
3533     4. Set the anchored flag if a branch starts with .* or .*? because that tests
3534     all possible positions.
3535    
3536     5. Split up into different modules to avoid including unneeded functions in a
3537     compiled binary. However, compile and exec are still in one module. The "study"
3538     function is split off.
3539    
3540     6. The character tables are now in a separate module whose source is generated
3541     by an auxiliary program - but can then be edited by hand if required. There are
3542     now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
3543     toupper() in the code.
3544    
3545     7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
3546     make them global. Abolish the function for setting them, as the caller can now
3547     set them directly.
3548    
3549    
3550     Version 0.92 11-Sep-97
3551     ----------------------
3552    
3553     1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
3554     (e.g. /a{1,3}/) was broken (I mis-optimized it).
3555    
3556     2. Caseless matching was not working in character classes if the characters in
3557     the pattern were in upper case.
3558    
3559     3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
3560    
3561     4. Make PCRE_ANCHORED public and accept as a compile option.
3562    
3563     5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
3564     PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
3565     pass them.
3566    
3567     6. Give an error if bad option bits passed at compile or run time.
3568    
3569     7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
3570     pcretest to cause it to pass that flag.
3571    
3572     8. Add pcre_info(), to get the number of identifying subpatterns, the stored
3573     options, and the first character, if set.
3574    
3575     9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
3576    
3577    
3578     Version 0.91 10-Sep-97
3579     ----------------------
3580    
3581     1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
3582     match the empty string as in /(a*)*/. It was looping and ultimately crashing.
3583    
3584     2. PCRE was looping on encountering an indefinitely repeated back reference to
3585     a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
3586     Perl does - treats the match as successful.
3587    
3588     ****

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